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https://en.wikipedia.org/wiki/Tetraview
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A tetraview is an attempt to graph a complex function of a complex variable, by a method invented by Davide P. Cervone.
A graph of a real function of a real variable is the set of ordered pairs (x,y) such that y = f(x). This is the ordinary two-dimensional Cartesian graph studied in school algebra.
Every complex number has both a real part and an imaginary part, so one complex variable is two-dimensional and a pair of complex variables is four-dimensional. A tetraview is an attempt to give a picture of a four-dimensional object using a two-dimensional representation—either on a piece of paper or on a computer screen, showing a still picture consisting of five views, one in the center and one at each corner. This is roughly analogous to a picture of a three-dimensional object by giving a front view, a side view, and a view from above.
A picture of a three-dimensional object is a projection of that object from three dimensions into two dimensions. A tetraview is set of five projections, first from four dimensions into three dimensions, and then from three dimensions into two dimensions.
A complex function w = f(z), where z = a + bi and w = c + di are complex numbers, has a graph in four-space (four dimensional space) R4 consisting of all points (a, b, c, d) such that c + di = f(a + bi).
To construct a tetraview, we begin with the four points (1,0,0,0), (0, 1, 0, 0), (0, 0, 1, 0), and (0, 0, 0, 1), which are vertices of a spherical tetrahedron on the unit three-sphere S3 in R4.
We project the four-dimensional graph onto the three-dimensional sphere along one of the four coordinate axes, and then give a two-dimensional picture of the resulting three-dimensional graph. This provides the four corner graph. The graph in the center is a similar picture "taken" from the point of view of the origin.
External links
http://www.math.union.edu/~dpvc/professional/art/tetra-exp.html
http://www.maa.org/cvm/1998/01/sbtd/article/tour/tetra-Z3/tetra-Z3.html
Functions an
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https://en.wikipedia.org/wiki/Microsoft%20Notification%20Protocol
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Microsoft Notification Protocol (MSNP, also known as the Mobile Status Notification Protocol) is an instant messaging protocol developed by Microsoft for use by the Microsoft Messenger service and the instant messaging clients that connect to it, such as Skype since 2014, and the earlier Windows Live Messenger, MSN Messenger, Windows Messenger, and Microsoft Messenger for Mac. Third-party clients such as Pidgin and Trillian can also communicate using the protocol. MSNP was first used in a publicly available product with the first release of MSN Messenger in 1999.
Technical details
Any major change made to the protocol, such as a new command or syntax changes, results in a version-number incremented by one in the format of MSNP#. During October 2003, Microsoft started blocking access to Messenger service using versions below MSNP8.
Starting on September 11, 2007, Microsoft forces most current users of MSN Messenger to upgrade to Windows Live Messenger 8.1 due to security considerations.
Version history
MSNP1
MSNP1 has never been public. It is believed it was used during the early stages of design and development with MSN Messenger 1
MSNP2
A pre-release version was made available to developers in 1999 in an Internet Draft. However, the production version differed from the published version in a few subtle ways.
MSNP3
Both MSNP2 and MSNP3 were supported by MSN Messenger 2.0. MSNP3 was also supported by the first version of the WebTV (MSN TV) Messenger client released in its Summer 2000 upgrade, and introduces a new command specifically for use by those clients — IMS — which allows the ability for a client to allow or block new switchboard sessions (chats) with other users at any point while the user is signed in.
MSNP4 and MSNP5
MSNP3, 4, and 5 were supported by the Messenger servers by July 2000 and used by MSN Messenger 3.0 and 4.0.
MSNP6 and MSNP7
MSNP6 was used by later versions of MSN Messenger 4.x. In 2002 MSN Messenger 5.0 used MSNP7.
MSNP8
MSNP8 intr
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https://en.wikipedia.org/wiki/Talkback%20%28recording%29
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In sound recording, a talkback system is the intercom used in recording studios and production control rooms (PCRs) in television studios to enable personnel to communicate with people in the recording area or booth. While the control room can hear the person in the booth over the studio microphones, the person in the booth hears the control room over a PA, monitor speaker, in their headphones or interruptible feedback (IFB) earpiece. Take numbers, reference data, and sometimes count-ins or remarks are also "stamped" onto recordings through talkback, similar to a clapperboard.
The audio quality of talkback systems is usually markedly lower than that of studio microphones and speakers, coming from a simple microphone (which may be omnidirectional or unidirectional) built or plugged into the audio mixer, and with its sound often compressed. Since talkback is usually edited out of master recordings, high fidelity isn't essential, and studios tend to cut budget corners when possible. Compression allows comments from around the control room to be audible.
Occasionally instructions and comments from talkback systems do appear in studio recordings, notably in records by The Beach Boys, The Beatles, Spoon, and Bob Dylan. They frequently turn up in bootleg or "sessions" records.
Recording
Telecommunications equipment
Broadcast engineering
Television terminology
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https://en.wikipedia.org/wiki/Elegant%20degradation
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Elegant degradation is a term used in engineering to describe what occurs to machines which are subject to constant, repetitive stress.
Externally, such a machine maintains the same appearance to the user, appearing to function properly. Internally, the machine slowly weakens over time. Eventually, unable to withstand the stress, it eventually breaks down. Compared to graceful degradation, the operational quality does not decrease at all, but the breakdown may be just as sudden.
This term's meaning varies depending on context and field, and may not be strictly considered exclusive to engineering. For instance, this is used as a mechanism in the food industry as applied in the degradation of lignin, cellulose, pentosan, and polymers, among others. The concept is also used to extract chemicals such as the elegant degradation of Paederus fuscipes to obtain pederin and hemiacetal pseuodopederin. In this process degradation is induced by heat. A play with the same name also used it as a metaphor for the current state of the world.
See also
Fail safe
Fail soft
References
Fault tolerance
Mechanical engineering
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https://en.wikipedia.org/wiki/User%20requirements%20document
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The user requirement(s) document (URD) or user requirement(s) specification (URS) is a document usually used in software engineering that specifies what the user expects the software to be able to do.
Once the required information is completely gathered it is documented in a URD, which is meant to spell out exactly what the software must do and becomes part of the contractual agreement. A customer cannot demand features not in the URD, while the developer cannot claim the product is ready if it does not meet an item of the URD.
The URD can be used as a guide for planning cost, timetables, milestones, testing, etc. The explicit nature of the URD allows customers to show it to various stakeholders to make sure all necessary features are described.
Formulating a URD requires negotiation to determine what is technically and economically feasible. Preparing a URD is one of those skills that lies between a science and an art, requiring both software technical skills and interpersonal skills.
Pharmaceutical Industry Use
User Requirement Specifications (URS) are important in the pharmaceutical industry for regulatory and business purposes. URS support regulatory and business considerations for processes, equipment, and systems. For example, a business consideration could be the foot print of equipment prior to installation to ensure there is enough room. Likewise, a regulatory consideration could be the ability for the system to provide an audit trail to ensure the system meets regulatory requirements.
URS writing pitfalls
Commonly, when companies are purchasing systems, processes, and equipment - not everything is considered. URS ensure everything is considered and the supplier provides the components, features, and design required to meet the company needs. By considering more and having the components, features, and design required, the system, process, or equipment can be aligned with company interests and easily integrated.
See also
Product requirements do
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https://en.wikipedia.org/wiki/Peetre%27s%20inequality
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In mathematics, Peetre's inequality, named after Jaak Peetre, says that for any real number and any vectors and in the following inequality holds:
The inequality was proved by J. Peetre in 1959 and has founds applications in functional analysis and Sobolev spaces.
See also
References
.
.
.
External links
Planetmath.org: Peetre's inequality
Functional analysis
Inequalities
Linear algebra
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https://en.wikipedia.org/wiki/Non-orientable%20wormhole
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In wormhole theory, a non-orientable wormhole is a wormhole connection that appears to reverse the chirality of anything passed through it. It is related to the "twisted" connections normally used to construct a Möbius strip or Klein bottle.
In topology, this sort of connection is referred to as an Alice handle.
Theory
"Normal" wormhole connection
Matt Visser has described a way of visualising wormhole geometry:
Take a "normal" region of space
"Surgically remove" spherical volumes from two regions ("spacetime surgery")
Associate the two spherical bleeding edges, so that a line attempting to enter one "missing" spherical volume encounters one bounding surface and then continues outward from the other.
Although these instructions seem straightforward, there are two topologically distinct ways the two surfaces can be mapped to one another. If we draw a map of the Earth's surface onto one wormhole mouth, how does this map appear at the second mouth?
For a "conventional" wormhole, the network of points will be seen at the second surface to be inverted, as if one surface was the mirror image of the other – countries will appear back-to-front, as will any text written on the map. This is as it should be, because in a sense, the second mouth is showing us the view of the same map seen "from the other side".
"Reversed" wormhole connection
The alternative way of connecting the surfaces makes the "connection map" appear the same at both mouths.
This configuration reverses the "handedness" or "chirality" of any objects passing through. If a spaceship pilot writes the word "IOTA" on the inside of their forward window, then, as the ship's nose passes through the wormhole and the ship's window intersects the surface, an observer at the other mouth looking in through the glass should see the same word, "IOTA", written on the window of the emerging spaceship. Once the spaceship has passed through, the curious onlooker may peek inside the spaceship cockpit and find tha
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https://en.wikipedia.org/wiki/Architecture%20for%20Control%20Networks
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Architecture for Control Networks (ACN) is a suite of network protocols for control of entertainment technology equipment, particularly as used in live performance or large-scale installations. For example, lighting, audio or special effects equipment. ACN is maintained by Entertainment Services and Technology Association and its first official release was ANSI Standard E1.17-2006 - Entertainment Technology - Architecture for Control Networks. The standard was subsequently revised and released as ANSI E1.17-2010.
ACN was initially designed to be layered on top of UDP/IP and therefore will run over most IP transports including standard, inexpensive Ethernet and 802.11 (Wi-Fi) networks.
Protocol architecture
ACN defines a common protocol architecture, two major network protocols (SDT, DMP), a device description language (DDL) and a number of ‘E1.17 Profiles for Interoperability’ (known as EPIs or interoperability profiles) which define how elements of the ACN architecture must be used in a particular context to achieve interoperability. For example, by providing specific values or ranges for timing parameters to be used in a particular network environment.
The breakdown of ACN into sub-protocols, interoperability profiles and other small pieces has been criticized as making ACN hard to read and understand but it makes the architecture highly modular and cleanly layered and this has allowed many of the pieces to be operated in other contexts or replaced or revised without changing the other pieces. For example, DMP has been operated over TCP as well as over SDT as defined in the initial standard, DDL has been adapted with little change to describe devices accessed by DMX512 (ANSI E1.31/Streaming ACN), and several interoperability profiles have seen major revision or replacement without disturbing the other parts of the standard.
Common Architecture
The common architecture specification defines a format of nested protocol data units (PDUs), rather similar to TLV
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https://en.wikipedia.org/wiki/Astalavista.box.sk
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astalavista.box.sk was founded in 1994 as one of the first search engines for computer security information. In practice it turned out to be used as a search engine for security exploits, software for hacking, cracking and different keygenerators and software cracks.
In the early 1990s and 2000s, the site was popular among people interested in hacking or securing systems against hacking. The site is known for referencing things such as spyware and viruses and because of this the website is known to possibly contain data, links, downloadable files, and information some users would consider spyware, adware, or other unwanted programs. Besides possible links to viruses, the website used to display adult adverts.
Previously, the website was part of a larger network of websites all using the box.sk domain. These websites all catered to different downloads, including MP3 music, DVD rips, and digital graphics and other hacking websites, such as New Order.
Astalavista.box.sk is hosted in Slovakia. Astalavista is a pun on the Spanish phrase "hasta la vista" (meaning "see you later"). It has been speculated that the name was a play on the 90's web search engine Altavista, however, that was launched a year later in 1995.
Astalavista.box.sk was not affiliated to astalavista.com, which was a separate hacking community, found in 1997.
On April 7, 2021, an article was published on Medium.com by Dancho Danchev stating that the site is back up and running. Subsequent attempts to reach the site however lead to a 503 Service Unavailable error on the website.
References
External links
Computing websites
Internet search engines
Computer security software
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https://en.wikipedia.org/wiki/Exception%20chaining
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Exception chaining, or exception wrapping, is an object-oriented programming technique of handling exceptions by re-throwing a caught exception after wrapping it inside a new exception. The original exception is saved as a property (such as cause) of the new exception. The idea is that a method should throw exceptions defined at the same abstraction level as the method itself, but without discarding information from the lower levels.
For example, a method to play a movie file might handle exceptions in reading the file by re-throwing them inside an exception of movie playing. The user interface doesn't need to know whether the error occurred during reading chunk of bytes or calling eof(). It needs only the exception message extracted from cause. The user interface layer will have its own set of exceptions. The one interested in cause can see its stack trace during debugging or in proper log.
Throwing the right kind of exceptions is particularly enforced by checked exceptions in the Java programming language, and starting with language version 1.4 almost all exceptions support chaining.
In runtime engine environments such as Java or .NET there exist tools that attach to the runtime engine and every time that an exception of interest occurs they record debugging information that existed in memory at the time the exception was thrown (stack and heap values). These tools are called Exception Interception and they provide "root-cause" information for exceptions in Java programs that run in production, testing, or development environments.
References
Chained exceptions - Sun's Java tutorial
Software design patterns
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https://en.wikipedia.org/wiki/Chainstore%20paradox
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The chainstore paradox is an apparent game theory paradox involving the chain store game, where a "deterrence strategy" appears optimal instead of the backward induction strategy of standard game theory reasoning.
The chain store game
A monopolist (Player A) has branches in 20 towns. He faces 20 potential competitors, one in each town, who will be able to choose or . They do so in sequential order and one at a time. If a potential competitor chooses , he receives a payoff of 1, while A receives a payoff of 5. If he chooses , he will receive a payoff of either 2 or 0, depending on the response of Player A to his action. Player A, in response to a choice of , must choose one of two pricing strategies, or . If he chooses , both player A and the competitor receive a payoff of 2, and if A chooses , each player receives a payoff of 0.
These outcomes lead to two theories for the game, the induction (game theoretically optimal version) and the deterrence theory (weakly dominated theory):
Induction theory
Consider the decision to be made by the 20th and final competitor, of whether to choose or . He knows that if he chooses , Player A receives a higher payoff from choosing cooperate than aggressive, and being the last period of the game, there are no longer any future competitors whom Player A needs to intimidate from the market. Knowing this, the 20th competitor enters the market, and Player A will cooperate (receiving a payoff of 2 instead of 0).
The outcome in the final period is set in stone, so to speak. Now consider period 19, and the potential competitor's decision. He knows that A will cooperate in the next period, regardless of what happens in period 19. Thus, if player 19 enters, an aggressive strategy will not be unable to deter player 20 from entering. Player 19 knows this and chooses . Player A chooses .
Of course, this process of backward induction holds all the way back to the first competitor. Each potential competitor chooses , and Player A always c
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https://en.wikipedia.org/wiki/Offset%20dish%20antenna
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An offset dish antenna or off-axis dish antenna is a type of parabolic antenna. It is so called because the antenna feed is offset to the side of the reflector, in contrast to the common "front-feed" parabolic antenna where the feed antenna is suspended in front of the dish, on its axis. As in a front-fed parabolic dish, the feed is located at the focal point of the reflector, but the reflector is an asymmetric segment of a paraboloid, so the focus is located to the side.
The purpose of this design is to move the feed antenna and its supports out of the path of the incoming radio waves. In an ordinary front-fed dish antenna, the feed structure and its supports are located in the path of the incoming beam of radio waves, partially obstructing them, casting a "shadow" on the dish, reducing the radio power received. In technical terms this reduces the aperture efficiency of the antenna, reducing its gain. In the offset design, the feed is positioned outside the area of the beam, usually below it on a boom sticking out from the bottom edge of the dish. The beam axis of the antenna, the axis of the incoming or outgoing radio waves, is skewed at an angle to the plane of the dish mouth.
The design is most widely used for small parabolic antennas or "mini-dishes", such as common home satellite television dishes, where the feed structure is large enough in relation to the dish to block a significant proportion of the signal. Another application is on satellites, particularly the direct broadcast satellites which use parabolic dishes to beam television signals to homes on Earth. Because of the limited transmitter power provided by their solar cells, satellite antennas must function as efficiently as possible. The offset design is also widely used in radar antennas. These must collect as much signal as possible in order to detect faint return signals from faraway targets.
Offset dish antennas are more difficult to design than front-fed antennas because the di
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https://en.wikipedia.org/wiki/C.%20Daniel%20Mote%20Jr.
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Clayton Daniel Mote Jr. (born February 5, 1937) is the President Emeritus of the National Academy of Engineering. He served as the president of the NAE from July 2013 to June 2019. He also served as President of the University of Maryland, College Park from September 1998 until August 2010. From 1967 to 1991, Mote was a professor in mechanical engineering at the University of California, Berkeley, and served as Vice Chancellor at Berkeley from 1991 to 1998. Mote is a judge for the Queen Elizabeth Prize for Engineering.
Academic career
University of California, Berkeley
Mote was born in San Francisco, California and received his bachelor's degree, masters, and doctorate degrees from the University of California, Berkeley in mechanical engineering. After a postdoctoral year in England and three years as an assistant professor at the Carnegie Institute of Technology in Pittsburgh, he returned to Berkeley to join the faculty in mechanical engineering for the next 31 years. He and his students investigated the dynamics, stability, and control of high-speed rotating and translating continua (e.g., disks, webs, tapes, and cables) as well as biomechanical problems emanating from snow skiing. He coined the area called "dynamics of axially moving materials" encompassing these systems. He has authored or co-authored over 300 academic publications, and has mentored 58 Ph.D. students. At Berkeley, he held an endowed chair in mechanical systems and served as chair of the mechanical engineering department from 1987 to 1991 when the National Research Council (NRC) ranked its graduate program effectiveness highest nationally. Because of his success at raising funds for mechanical engineering, in 1991 he was appointed vice chancellor at Berkeley expressly to create and lead a $1 billion capital campaign for the campus that ultimately reached $1.4 billion.
University of Maryland
In 1998, Dr. Mote was recruited to the presidency of the University of Maryland, College Park, a positio
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https://en.wikipedia.org/wiki/Astron%20Belt
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Astron Belt (アストロンベルト) is a LaserDisc video game in the form of a third-person, space combat rail shooter, released in arcades in 1983 by Sega in Japan, and licensed to Bally Midway for release in North America. Developed in 1982, it was the first major arcade laserdisc video game. The game combines full-motion video (FMV) footage from the laserdisc with real-time 2D graphics. The arcade game was available in both upright and cockpit arcade cabinets, with the latter having illuminated buttons on the control panel, a larger 25" monitor (the upright used a standard 19"), and a force feedback vibrating seat.
The game was first unveiled at the 20th Amusement Machine Show, held in Tokyo during September 1982, and then at Chicago's Amusement & Music Operators Association (AMOA) show, held during November 18–20, 1982. This marked the beginning of laserdisc fever in the video game industry, and released in Japan during early 1983, with Sega projecting to ship 10,000 cabinets that year. It was subsequently released in Europe, where it was the first laserdisc game released in the region. However, Bally Midway delayed the game's release in the United States to fix several hardware and software bugs, by which time it had been beaten to public release by several laserdisc games including Dragon's Lair.
The game was a commercial success in arcades, especially in Japan where it was the top-grossing upright/cockpit arcade game for four months. Critical reception was initially positive following its AMOA 1982 debut and then its European release, but was later mixed following its North American release as it drew unfavorable comparisons with other laserdisc games. Astron Belt was ported to the MSX home system in 1984 in Japan.
Gameplay
The player controls a lone spacecraft on a mission to singlehandedly take down the entire enemy armada. Enemy fighters and ships shoot at the player, and there are mines and other objects that must be shot or avoided.
The game is divided into waves
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https://en.wikipedia.org/wiki/Myhill%20isomorphism%20theorem
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In computability theory the Myhill isomorphism theorem, named after John Myhill, provides a characterization for two numberings to induce the same notion of computability on a set.
Theorem
Definitions
Sets A and B of natural numbers are said to be recursively isomorphic if there is a total computable bijective function f on the natural numbers such that for any , .
A set A of natural numbers is said to be one-one reducible to a set B if there is a total computable injective function f on the natural numbers such that and .
Stetement
Myhill's isomorphism theorem states that two sets A and B of natural numbers are recursively isomorphic if and only if A is one-reducible to B and B is one-reducible to A.
Corollaries
Two total numberings are one-equivalent if and only if they are recursively isomorphic.
Discussion
The theorem implies that given two injective reductions in opposing directions, there is a computable bijection on the naturals that puts the sets in question in bijective correspondence. This is reminiscent of the Schröder–Bernstein theorem about general sets, and Myhill's theorem has been called a constructive version of it.
Their proofs are however different. The proof of Schröder-Bernstein uses the inverses of the two injections, which is impossible in the setting of the Myhill theorem since these inverses might not be recursive. The proof of the Myhill theorem, on the other hand, defines the bijection inductively, which is impossible in the setting of Schröder-Bernstein unless one uses the Axiom of Choice (which is not necessary for the proof of the Myhill theorem).
See also
Berman–Hartmanis conjecture, an analogous statement in computational complexity theory
References
.
.
Soare, Robert I. (1987), Recursively enumerable sets and degrees : a study of computable functions and computably generated sets, Perspectives in Mathematical Logic, Berlin Heidelberg : Springer-Verlag, ISBN 978-3-540-66681-3, MR 0882921
Computability theory
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https://en.wikipedia.org/wiki/Product%20and%20manufacturing%20information
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Product and manufacturing information, also abbreviated PMI, conveys non-geometric attributes in 3D computer-aided design (CAD) and Collaborative Product Development systems necessary for manufacturing product components and assemblies. PMI may include geometric dimensions and tolerances, 3D annotation (text) and dimensions, surface finish, and material specifications. PMI is used in conjunction with the 3D model within model-based definition to allow for the elimination of 2D drawings for data set utilization.
Uses and visualization
The PMI annotation is created on the 3D CAD model, associated to edges and faces, and can be exported into neutral formats such as ISO 10303 STEP and 3D PDF. This information can then be used by a number of down-stream processes. PMI can be used to generate annotation on a traditional 2D drawing the data. However, generally, PMI is used to visualized product definition within the 3D model, thus removing the need for drawings. Some 3D model formats enable computer-aided manufacturing software to access PMI directly for CNC programming. The PMI also may be used by tolerance analysis and coordinate-measuring machine (CMM) software applications if the modeling application permits.
PMI items are often organized within annotation views. Annotation views typically view including camera/view position, selected and also the particular state of the assembly (visibility, rendering mode, sometime even position of each element of the assembly). CAD applications have different notions of PMI Views (for instance "Capture Views" and "Annotation
Views" are specific to Dassault Systems CATIA, etc.).
For anyone to be able to display any kind of PMI View, Adobe Systems has unified their format and added their description to the PDF format (version 1.7).
Communication deliverables
In an effort to unify the visualization of PMI across the different existing solutions, Adobe Systems has released a version of the Myriad CAD font that allows disp
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https://en.wikipedia.org/wiki/Messaging%20pattern
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In software architecture, a messaging pattern is an architectural pattern which describes how two different parts of an application, or different systems connect and communicate with each other. There are many aspects to the concept of messaging which can be divided in the following categories: hardware device messaging (telecommunications, computer networking, IoT, etc.) and software data exchange (the different data exchange formats and software capabilities of such data exchange). Despite the difference in the context, both categories exhibit common traits for data exchange.
General concepts of the messaging pattern
In telecommunications, a message exchange pattern (MEP) describes the pattern of messages required by a communications protocol to establish or use a communication channel. The communications protocol is the format used to represent the message which all communicating parties agree on (or are capable to process). The communication channel is the infrastructure that enables messages to "travel" between the communicating parties. The message exchange patterns describe the message flow between parties in the communication process, there are two major message exchange patterns — a request–response pattern, and a one-way pattern.
For example, when viewing content on the Internet (the channel), a web browser (a communicating party) would use the HTTP (the communication protocol) to request a web page from the server (another communicating party), and then render the returned data into its visual form. This is how the request–response messaging pattern operates.
Alternatively, in computer networking, we have the UDP network protocol. It is used with the one-way messaging pattern, where the sending party is not interested whether the message arrives to any receiving party, nor it expects any of the receiving parties to produce an "answering" message.
Device communication
This section is about data exchange between hardware devices. In order for the de
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https://en.wikipedia.org/wiki/Almost%20convergent%20sequence
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A bounded real sequence is said to be almost convergent to if each Banach limit assigns
the same value to the sequence .
Lorentz proved that is almost convergent if and only if
uniformly in .
The above limit can be rewritten in detail as
Almost convergence is studied in summability theory. It is an example of a summability method
which cannot be represented as a matrix method.
References
G. Bennett and N.J. Kalton: "Consistency theorems for almost convergence." Trans. Amer. Math. Soc., 198:23--43, 1974.
J. Boos: "Classical and modern methods in summability." Oxford University Press, New York, 2000.
J. Connor and K.-G. Grosse-Erdmann: "Sequential definitions of continuity for real functions." Rocky Mt. J. Math., 33(1):93--121, 2003.
G.G. Lorentz: "A contribution to the theory of divergent sequences." Acta Math., 80:167--190, 1948.
.
Specific
Convergence (mathematics)
Sequences and series
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https://en.wikipedia.org/wiki/Object-oriented%20analysis%20and%20design
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Object-oriented analysis and design (OOAD) is a technical approach for analyzing and designing an application, system, or business by applying object-oriented programming, as well as using visual modeling throughout the software development process to guide stakeholder communication and product quality.
OOAD in modern software engineering is typically conducted in an iterative and incremental way. The outputs of OOAD activities are analysis models (for OOA) and design models (for OOD) respectively. The intention is for these to be continuously refined and evolved, driven by key factors like risks and business value.
History
In the early days of object-oriented technology before the mid-1990s, there were many different competing methodologies for software development and object-oriented modeling, often tied to specific Computer Aided Software Engineering (CASE) tool vendors. No standard notations, consistent terms and process guides were the major concerns at the time, which degraded communication efficiency and lengthened learning curves.
Some of the well-known early object-oriented methodologies were from and inspired by gurus such as Grady Booch, James Rumbaugh, Ivar Jacobson (the Three Amigos), Robert Martin, Peter Coad, Sally Shlaer, Stephen Mellor, and Rebecca Wirfs-Brock.
In 1994, the Three Amigos of Rational Software started working together to develop the Unified Modeling Language (UML). Later, together with Philippe Kruchten and Walker Royce (eldest son of Winston Royce), they have led a successful mission to merge their own methodologies, OMT, OOSE and Booch method, with various insights and experiences from other industry leaders into the Rational Unified Process (RUP), a comprehensive iterative and incremental process guide and framework for learning industry best practices of software development and project management. Since then, the Unified Process family has become probably the most popular methodology and reference model for object-oriented a
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https://en.wikipedia.org/wiki/True%20RMS%20converter
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For the measurement of an alternating current the signal is often converted into a direct current of equivalent value, the root mean square (RMS). Simple instrumentation and signal converters carry out this conversion by filtering the signal into an average rectified value and applying a correction factor. The value of the correction factor applied is only correct if the input signal is sinusoidal.
True RMS provides a more correct value that is proportional to the square root of the average of the square of the curve, and not to the average of the absolute value. For any given waveform, the ratio of these two averages is constant and, as most measurements are made on what are (nominally) sine waves, the correction factor assumes this waveform; but any distortion or offsets will lead to errors. To achieve this, a true RMS converter requires a more complex circuit.
Digital RMS converters
If a waveform has been digitized, the correct RMS value may be calculated directly. Most digital and PC-based oscilloscopes include a function to give the RMS value of a waveform. The precision and the bandwidth of the conversion is entirely dependent on the analog to digital conversion. In most cases, true RMS measurements are made on repetitive waveforms, and under such conditions digital oscilloscopes (and a few sophisticated sampling multimeters) are able to achieve very high bandwidths as they sample at much higher sampling frequency than the signal frequency to obtain a stroboscopic effect.
Thermal converters
The RMS value of an alternating current is also known as its heating value, as it is a voltage which is equivalent to the direct current value that would be required to get the same heating effect. For example, if 120 V AC RMS is applied to a resistive heating element it would heat up by exactly the same amount as if 120 V DC were applied.
This principle was exploited in early thermal converters. The AC signal would be applied to a small heating element that was matched
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https://en.wikipedia.org/wiki/The%20Business%20Cloud
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The Business Cloud is an API enabled self-service platform, developed by Domo, that provides an array of services like data connection and data visualization.
History
Domo, Inc. was founded in 2010 by Josh James who also co-founded the web analytics software company Omniture in 1996, which he took public in 2006.
Domo launched the Domo Appstore, with a 1000 apps with social and mobile capabilities, in 2016. This appstore creates a network of business apps and an ecosystem of companies into a single, integrated business cloud. This decision came after Domo announced a $131 million round of funding from BlackRock.
According to the company, the concept behind The Business Cloud is to connect smaller clouds relating to apps or other functional areas of a business into a single business cloud that allows self-service and other social features to customers.
Services
The Business Cloud is offered as a free service, claimed to be the world's first business cloud with Domo appstore as one of its core services. This free package includes all of the Domo's features and functionality including Domo platform, Domo Apps, visualizations, alerts, company directories, org charts, profiles, tasks and Domo Mobile. The Business Cloud allows customers to leverage their preferred cloud as well as on-premises software and monitor all aspects of their business in routine.
The company is supported by a $500 million fund from investors all over the world.
References
External links
Business Cloud Official Website
Workday - Cloud Hosted Software
Cloud computing
Cloud applications
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https://en.wikipedia.org/wiki/MasPar
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MasPar Computer Corporation was a minisupercomputer vendor that was founded in 1987 by Jeff Kalb. The company was based in Sunnyvale, California.
History
While Kalb was the vice-president of the division of Digital Equipment Corporation (DEC) that built integrated circuits, some researchers in that division were building a supercomputer based on the Goodyear MPP (massively parallel processor) supercomputer. The DEC researchers enhanced the architecture by:
making the processor elements to be 4-bit instead of 1-bit
increasing the connectivity of each processor element to 8 neighbors from 4.
adding a global interconnect for all of the processing elements, which was a triple-redundant switch which was easier to implement than a full crossbar switch.
After Digital decided not to commercialize the research project, Kalb decided to start a company to sell this minisupercomputer. In 1990, the first generation product MP-1 was delivered. In 1992, the follow-on MP-2 was shipped. The company shipped more than 200 systems.
MasPar along with nCUBE criticized the open government support, by DARPA, of competitors Intel for their hypercube Personal SuperComputers (iPSC) and the Thinking Machines Connection Machine on the pages of Datamation.
Samples of MasPar MPs, from the NASA Goddard Space Flight Center, are in storage at the Computer History Museum.
MasPar offered a family of SIMD machines, second sourced by DEC. The processor units are proprietary.
There was no MP-3. MasPar exited the computer hardware business in June 1996, halting all hardware development and transforming itself into a new data mining software company called NeoVista Software. NeoVista was acquired by Accrue Software in 1999, which in turn sold the division to JDA Software in 2001.
Hardware
MasPar is unique in being a manufacturer of SIMD supercomputers (as opposed to vector machines). In this approach, a collection of ALU's listen to a program broadcast from a central source. The ALUs can do t
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https://en.wikipedia.org/wiki/Omega%20network
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An Omega network is a network configuration often used in parallel computing architectures. It is an indirect topology that relies on the perfect shuffle interconnection algorithm.
Connection architecture
An 8x8 Omega network is a multistage interconnection network, meaning that processing elements (PEs) are connected using multiple stages of switches. Inputs and outputs are given addresses as shown in the figure. The outputs from each stage are connected to the inputs of the next stage using a perfect shuffle connection system. This means that the connections at each stage represent the movement of a deck of cards divided into 2 equal decks and then shuffled together, with each card from one deck alternating with the corresponding card from the other deck. In terms of binary representation of the PEs, each stage of the perfect shuffle can be thought of as a cyclic logical left shift; each bit in the address is shifted once to the left, with the most significant bit moving to the least significant bit.
At each stage, adjacent pairs of inputs are connected to a simple exchange element, which can be set either straight (pass inputs directly through to outputs) or crossed (send top input to bottom output, and vice versa). For N processing element, an Omega network contains N/2 switches at each stage, and log2N stages. The manner in which these switches are set determines the connection paths available in the network at any given time. Two such methods are destination-tag routing and XOR-tag routing, discussed in detail below.
The Omega Network is highly blocking, though one path can always be made from any input to any output in a free network.
Destination-tag routing
In destination-tag routing, switch settings are determined solely by the message destination. The most significant bit of the destination address is used to select the output of the switch in the first stage; if the most significant bit is 0, the upper output is selected, and if it is 1, the lower out
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https://en.wikipedia.org/wiki/Pole%20figure
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A pole figure is a graphical representation of the orientation of objects in space. For example, pole figures in the form of stereographic projections are used to represent the orientation distribution of crystallographic lattice planes in crystallography and texture analysis in materials science.
Definition
Consider an object with a basis attached to it. The orientation of the object in space can be determined by three rotations to transform the reference basis of space to the basis attached to the object; these are the Euler angles.
If we consider a plane of the object, the orientation of the plane can be given by its normal line. If we draw a sphere with the center on the plane, then
the intersection of the sphere and the plane is a circle, called the "trace" ;
the intersection of the normal line and the sphere is the pole.
A single pole is not enough to fully determine the orientation of an object: the pole stays the same if we apply a rotation around the normal line. The orientation of the object is fully determined by the use of poles of two planes that are not parallel.
Stereographic projection
The upper sphere is projected on a plane using the stereographic projection.
Consider the (x,y) plane of the reference basis; its trace on the sphere is the equator of the sphere. We draw a line joining the South pole with the pole of interest P.
It is possible to choose any projection plane parallel to the equator (except the South pole): the figures will be proportional (property of similar triangles). It is usual to place the projection plane at the North pole.
Definition
The pole figure is the stereographic projection of the poles used to represent the orientation of an object in space.
Geometry in the pole figure
A Wulff net is used to read a pole figure.
The stereographic projection of a trace is an arc. The Wulff net is arcs corresponding to planes that share a common axis in the (x,y) plane.
If the pole and the trace of a plane are represented
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https://en.wikipedia.org/wiki/Drillship
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A drillship is a merchant vessel designed for use in exploratory offshore drilling of new oil and gas wells or for scientific drilling purposes. In recent years the vessels have been used in deepwater and ultra-deepwater applications, equipped with the latest and most advanced dynamic positioning systems.
History
The first drillship was the CUSS I, designed by Robert F. Bauer of Global Marine in 1955. The CUSS I had drilled in 400-foot-deep waters by 1957.
Robert F. Bauer became the first president of Global Marine in 1958.
In 1961 Global Marine started a new drillship era. They ordered several self-propelled drillships each with a rated centerline drilling of 20,000 foot-wells in water depths of 600 feet. The first was named CUSS (Glomar) II, a 5,500-deadweight-ton vessel, costing around $4.5 million. Built by a Gulf Coast shipyard, the vessel was almost twice the size of the CUSS I, and became the world's first drillship built as a new construction which set sail in 1962.
In 1962, The Offshore Company elected to build a new type of drillship, larger than that of the Glomar class. This new drillship would feature a first-ever anchor mooring array based on a unique turret system. The vessel was named Discoverer I. The Discoverer I had no main propulsion engines, meaning it needed to be towed out to the drill site.
Application
A drillship can be used as a platform to carry out well maintenance or completion work such as casing and tubing installation, subsea tree installations, and well capping. Drillships are often built to the design specifications set by the oil production company and/or investors.
From the first drillship CUSS I to the Deepwater Asgard, the fleet size has been growing ever since. In 2013 the worldwide fleet of drillships topped 80 ships, more than double its size in 2009. Drillships are not only growing in size but also in capability, with new technology assisting operations from academic research to ice-breaker class drilling vessels. U.S.
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https://en.wikipedia.org/wiki/Erd%C5%91s%E2%80%93Woods%20number
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In number theory, a positive integer is said to be an Erdős–Woods number if it has the following property:
there exists a positive integer such that in the sequence of consecutive integers, each of the elements has a non-trivial common factor with one of the endpoints. In other words, is an Erdős–Woods number if there exists a positive integer such that for each integer between and , at least one of the greatest common divisors or is greater than .
Examples
The first Erdős–Woods numbers are
16, 22, 34, 36, 46, 56, 64, 66, 70, 76, 78, 86, 88, 92, 94, 96, 100, 106, 112, 116 … .
History
Investigation of such numbers stemmed from the following prior conjecture by Paul Erdős:
There exists a positive integer such that every integer is uniquely determined by the list of prime divisors of .
Alan R. Woods investigated this question for his 1981 thesis. Woods conjectured that whenever , the interval always includes a number coprime to both endpoints. It was only later that he found the first counterexample, , with . The existence of this counterexample shows that 16 is an Erdős–Woods number.
proved that there are infinitely many Erdős–Woods numbers, and showed that the set of Erdős–Woods numbers is recursive.
References
External links
Woods number
Integer sequences
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https://en.wikipedia.org/wiki/Montonen%E2%80%93Olive%20duality
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Montonen–Olive duality or electric–magnetic duality is the oldest known example of strong–weak duality or S-duality according to current terminology. It generalizes the electro-magnetic symmetry of Maxwell's equations by stating that magnetic monopoles, which are usually viewed as emergent quasiparticles that are "composite" (i.e. they are solitons or topological defects), can in fact be viewed as "elementary" quantized particles with electrons playing the reverse role of "composite" topological solitons; the viewpoints are equivalent and the situation dependent on the duality. It was later proven to hold true when dealing with a N = 4 supersymmetric Yang–Mills theory. It is named after Finnish physicist Claus Montonen and British physicist David Olive after they proposed the idea in their academic paper Magnetic monopoles as gauge particles? where they state:
S-duality is now a basic ingredient in topological quantum field theories and string theories, especially since the 1990s with the advent of the second superstring revolution. This duality is now one of several in string theory, the AdS/CFT correspondence which gives rise to the holographic principle, being viewed as amongst the most important. These dualities have played an important role in condensed matter physics, from predicting fractional charges of the electron, to the discovery of the magnetic monopole.
Electric–magnetic duality
The idea of a close similarity between electricity and magnetism, going back to the time of André-Marie Ampère and Michael Faraday, was first made more precise with James Clerk Maxwell's formulation of his famous equations for a unified theory of electric and magnetic fields:
The symmetry between and in these equations is striking. If one ignores the sources, or adds magnetic sources, the equations are invariant under and .
Why should there be such symmetry between and ? In 1931 Paul Dirac was studying the quantum mechanics of an electric charge moving in a magnetic
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https://en.wikipedia.org/wiki/Nielsen%E2%80%93Olesen%20vortex
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In theoretical physics, a Nielsen–Olesen vortex is a point-like object localized in two spatial dimensions or, equivalently, a classical solution of field theory with the same property. This particular solution occurs if the configuration space of scalar fields contains non-contractible circles. A circle surrounding the vortex at infinity may be "wrapped" once on the other circle in the configuration space. A configuration with this non-trivial topological property is called the Nielsen–Olesen vortex, after Holger Bech Nielsen and Poul Olesen (1973). The solution is formally identical to the solution of Quantum vortex in superconductor.
See also
Nielsen–Olsen string
Abrikosov vortex
Montonen–Olive duality
S-duality
References
Quantum field theory
Vortices
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https://en.wikipedia.org/wiki/MotoMagx
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MotoMagx was a Linux kernel-based mobile operating system developed and launched in 2007 by Motorola to run on their mid-to-high-end mobile phones. The system was based on MontaVista's Mobilinux. Originally intended for 60% of their upcoming devices, it was soon dropped in favor of Android and Windows Mobile operating systems.
MOTOMAGX was only compatible with Motorola's GSM/UMTS devices (as shown below). This was due to the lack of an implementation compatible with Qualcomm CDMA2000 devices. As a result, Motorola often sold multiple device variants with radically different firmware. For example, the Motorola RAZR2 on T-Mobile shipped with MOTOMAGX, whereas the RAZR2 on Verizon Wireless shipped with Motorola's P2k firmware.
This created significant confusion for customers, as the user experience varied widely between two otherwise identical devices, simply based on which carrier they were on.
Devices
Phones based on this OS are:
Motorola EM30
Motorola ROKR E2
Motorola ROKR E8
Motorola ROKR/RIZR Z6
Motorola U9
Motorola RAZR2 V8
Motorola VE66
Motorola ZINE ZN5
Motorola Tundra V76r
Motorola ROKR EM35
Motorola ROKR ZN200
References
Introducing MOTOMAGX
MOTODEV > Technologies > MOTOMAGX
Embedded Linux distributions
Mobile operating systems
Linux distributions
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https://en.wikipedia.org/wiki/G-LOC
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g-force induced loss of consciousness (abbreviated as G-LOC, pronounced "JEE-lock") is a term generally used in aerospace physiology to describe a loss of consciousness occurring from excessive and sustained g-forces draining blood away from the brain causing cerebral hypoxia. The condition is most likely to affect pilots of high performance fighter and aerobatic aircraft or astronauts but is possible on some extreme amusement park rides. G-LOC incidents have caused fatal accidents in high performance aircraft capable of sustaining high g for extended periods. High-g training for pilots of high performance aircraft or spacecraft often includes ground training for G-LOC in special centrifuges, with some profiles exposing pilots to 9 gs for a sustained period.
Effects of g-forces
Under increasing positive g-force, blood in the body will tend to move from the head toward the feet. For higher intensity or longer duration, this can manifest progressively as:
Tunnel vision – loss of peripheral vision, retaining only the center vision
Greyout – a loss of color vision
Blackout – a complete loss of vision but retaining consciousness.
G-LOC – where consciousness is lost.
Under negative g, blood pressure will increase in the head, running the risk of the dangerous condition known as redout, with too much blood pressure in the head and eyes.
Because of the high level of sensitivity that the eye’s retina has to hypoxia, symptoms are usually first experienced visually. As the retinal blood pressure decreases below Intraocular pressure (usually 10–21 mm Hg), blood flow begins to cease to the retina, first affecting perfusion farthest from the optic disc and central retinal artery with progression towards central vision. Skilled pilots can use this loss of vision as their indicator that they are at maximum turn performance without losing consciousness. Recovery is usually prompt following removal of g-force but a period of several seconds of disorientation may occur. Ab
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https://en.wikipedia.org/wiki/AMD%20FirePro
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AMD FirePro was AMD's brand of graphics cards designed for use in workstations and servers running professional Computer-aided design (CAD), Computer-generated imagery (CGI), Digital content creation (DCC), and High-performance computing/GPGPU applications. The GPU chips on FirePro-branded graphics cards are identical to the ones used on Radeon-branded graphics cards. The end products (i.e. the graphics card) differentiate substantially by the provided graphics device drivers and through the available professional support for the software. The product line is split into two categories: "W" workstation series focusing on workstation and primarily focusing on graphics and display, and "S" server series focused on virtualization and GPGPU/High-performance computing.
The release of the Radeon Pro Duo in April 2016 and the announcement of the Radeon Pro WX Series in July 2016 marked the succession of Radeon Pro as AMD's professional workstation graphics card solution. Radeon Instinct is the current brand for servers.
Competitors included Nvidia's Quadro-branded and to an extent, Nvidia Tesla-branded product series and Intel's Xeon Phi-branded products.
History
The FireGL line was originally developed by the German company Spea Software AG until it was acquired by Diamond Multimedia in November 1995. The first FireGL board used the 3Dlabs GLINT 3D processor chip.
Deprecated brand names are ATI FireGL, ATI FirePro 3D, and AMD FireStream.
In July 2016, AMD announced it would be replacing the FirePro brand with Radeon Pro for workstations. The new brand for servers is Radeon Instinct.
Features
Multi-monitor support
AMD Eyefinity can support multi-monitor set-ups. One graphics card can drive up to a maximum of six monitors; the supported number depends on the distinct product and the number of DisplayPort displays. The device driver facilitates the configuration of diverse display group modes.
Differences with the Radeon Line
The FirePro line is designed for comput
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https://en.wikipedia.org/wiki/Valve%20Anti-Cheat
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Valve Anti-Cheat (VAC) is an anti-cheat tool developed by Valve as a component of the Steam platform, first released with Counter-Strike in 2002.
When the software detects a cheat on a player's system, it will ban them in the future, possibly days or weeks after the original detection. It may kick players from the game if it detects errors in their system's memory or hardware. No information such as date of detection or type of cheat detected is disclosed to the player. After the player is notified, access to online "VAC protected" servers of the game the player cheated in is permanently revoked and additional restrictions are applied to the player's Steam account.
During one week of November 2006, the system detected over 10,000 cheating attempts.
During the month of December 2018 over 600,000 accounts were banned.
History
In 2001, Even Balance Inc., the developers of the anti-cheat software PunkBuster designed for Counter-Strike and Half-Life mods, stopped supporting the games as they had no support from Valve. Valve had also rejected business offers of integrating the technology directly into their games.
Valve started working on a "long-term solution" for cheating in 2001. VAC's initial release was with Counter-Strike in 2002. During this initial release, the system only banned players for 24 hours. The duration of the ban was increased over time; players were banned for 1 year and 5 years, until VAC2 was released in 2005, when any new bans became permanent. VAC2 was announced in February 2005 and began beta testing the following month. On November 17, 2006, they announced that "new [VAC] technology" had caught "over 10,000" cheating attempts in the preceding week alone.
During the early testing phase in 2002, some information was revealed about the program via the Half-Life Dedicated Server mailing lists. It can detect versions of "OGC's OpenGl Hack", can detect OpenGL cheats, and also detects CD key changers as cheats. Information on detected cheaters is
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https://en.wikipedia.org/wiki/Faithful%20representation
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In mathematics, especially in an area of abstract algebra known as representation theory, a faithful representation ρ of a group on a vector space is a linear representation in which different elements of are represented by distinct linear mappings .
In more abstract language, this means that the group homomorphism is injective (or one-to-one).
Caveat
While representations of over a field are de facto the same as -modules (with denoting the group algebra of the group ), a faithful representation of is not necessarily a faithful module for the group algebra. In fact each faithful -module is a faithful representation of , but the converse does not hold. Consider for example the natural representation of the symmetric group in dimensions by permutation matrices, which is certainly faithful. Here the order of the group is while the matrices form a vector space of dimension . As soon as is at least 4, dimension counting means that some linear dependence must occur between permutation matrices (since ); this relation means that the module for the group algebra is not faithful.
Properties
A representation of a finite group over an algebraically closed field of characteristic zero is faithful (as a representation) if and only if every irreducible representation of occurs as a subrepresentation of (the -th symmetric power of the representation ) for a sufficiently high . Also, is faithful (as a representation) if and only if every irreducible representation of occurs as a subrepresentation of
(the -th tensor power of the representation ) for a sufficiently high .
References
Representation theory
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https://en.wikipedia.org/wiki/Gravitational%20instanton
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In mathematical physics and differential geometry, a gravitational instanton is a four-dimensional complete Riemannian manifold satisfying the vacuum Einstein equations. They are so named because they are analogues in quantum theories of gravity of instantons in Yang–Mills theory. In accordance with this analogy with self-dual Yang–Mills instantons, gravitational instantons are usually assumed to look like four dimensional Euclidean space at large distances, and to have a self-dual Riemann tensor. Mathematically, this means that they are asymptotically locally Euclidean (or perhaps asymptotically locally flat) hyperkähler 4-manifolds, and in this sense, they are special examples of Einstein manifolds. From a physical point of view, a gravitational instanton is a non-singular solution of the vacuum Einstein equations with positive-definite, as opposed to Lorentzian, metric.
There are many possible generalizations of the original conception of a gravitational instanton: for example one can allow gravitational instantons to have a nonzero cosmological constant or a Riemann tensor which is not self-dual. One can also relax the boundary condition that the metric is asymptotically Euclidean.
There are many methods for constructing gravitational instantons, including the Gibbons–Hawking Ansatz, twistor theory, and the hyperkähler quotient construction.
Introduction
Gravitational instantons are interesting, as they offer insights into the quantization of gravity. For example, positive definite asymptotically locally Euclidean metrics are needed as they obey the positive-action conjecture; actions that are unbounded below create divergence in the quantum path integral.
A four-dimensional Kähler–Einstein manifold has a self-dual Riemann tensor.
Equivalently, a self-dual gravitational instanton is a four-dimensional complete hyperkähler manifold.
Gravitational instantons are analogous to self-dual Yang–Mills instantons.
Several distinctions can be made with respect to
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https://en.wikipedia.org/wiki/Job%20Submission%20Description%20Language
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Job Submission Description Language is an extensible XML specification from the Global Grid Forum for the description of simple tasks to non-interactive computer execution systems. Currently at version 1.0 (released November 7, 2005), the specification focuses on the description of computational task submissions to traditional high-performance computer systems like batch schedulers.
Description
JSDL describes the submission aspects of a job, and does not attempt to describe the state of running or historic jobs. Instead, JSDL includes descriptions of:
Job name, description
Resource requirements that computers must have to be eligible for scheduling, such as total RAM available, total swap available, CPU clock speed, number of CPUs, Operating System, etc.
Execution limits, such as the maximum amount of CPU time, wallclock time, or memory that can be consumed.
File staging, or the transferring of files before or after execution.
Command to execute, including its command-line arguments, environment variables to define, stdin/stdout/stderr redirection, etc.
Software support
The following software is known to currently support JSDL:
GridWay meta scheduler
Platform LSF 7
UNICORE 6
GridSAM
Windows HPC Server 2008
GRIA
Genesis II Project http://genesis2.virginia.edu/wiki/
Advanced Resource Connector (ARC v0.6 and above)
XtreemOS Grid Operating System
EMOTIVE Cloud
IBM Tivoli Workload Scheduler Tivoli Workload Scheduler
See also
Resource Specification Language (See The Globus Resource Specification Language RSL v1.0)
Distributed Resource Management Application API
External links
JSDL working group project page
Windows HPC Server 2008
Grid computing
XML-based standards
Computer-related introductions in 2005
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https://en.wikipedia.org/wiki/Coordinate-measuring%20machine
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A coordinate measuring machine (CMM) is a device that measures the geometry of physical objects by sensing discrete points on the surface of the object with a probe. Various types of probes are used in CMMs, the most common being mechanical and laser sensors, though optical and white light sensor do exist. Depending on the machine, the probe position may be manually controlled by an operator or it may be computer controlled. CMMs typically specify a probe's position in terms of its displacement from a reference position in a three-dimensional Cartesian coordinate system (i.e., with XYZ axes). In addition to moving the probe along the X, Y, and Z axes, many machines also allow the probe angle to be controlled to allow measurement of surfaces that would otherwise be unreachable.
Description
The typical 3D "bridge" CMM allows probe movement along three axes, X, Y and Z, which are orthogonal to each other in a three-dimensional Cartesian coordinate system. Each axis has a sensor that monitors the position of the probe on that axis, with typical accuracy in the order of microns. When the probe contacts (or otherwise detects) a particular location on the object, the machine samples the axis position sensors, thus measuring the location of one point on the object's surface, as well as the 3-dimensional vector of the measurement taken. This process is repeated as necessary, moving the probe each time, to produce a "point cloud" which describes the surface areas of interest. The points can be measured either manually by an operator or automatically via Direct Computer Control (DCC) or automatically using scripted programs; thus, an automated CMM is a specialized form of industrial robot.
A common use of CMMs is in manufacturing and assembly processes to test a part or assembly against the design intent. The measured points can be used to verify the distance between features. They can also be used to construct geometric features such as cylinders and planes etc. for GD&T su
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https://en.wikipedia.org/wiki/Ionic%20strength
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The ionic strength of a solution is a measure of the concentration of ions in that solution. Ionic compounds, when dissolved in water, dissociate into ions. The total electrolyte concentration in solution will affect important properties such as the dissociation constant or the solubility of different salts. One of the main characteristics of a solution with dissolved ions is the ionic strength. Ionic strength can be molar (mol/L solution) or molal (mol/kg solvent) and to avoid confusion the units should be stated explicitly. The concept of ionic strength was first introduced by Lewis and Randall in 1921 while describing the activity coefficients of strong electrolytes.
Quantifying ionic strength
The molar ionic strength, I, of a solution is a function of the concentration of all ions present in that solution.
where one half is because we are including both cations and anions, ci is the molar concentration of ion i (M, mol/L), zi is the charge number of that ion, and the sum is taken over all ions in the solution. For a 1:1 electrolyte such as sodium chloride, where each ion is singly-charged, the ionic strength is equal to the concentration. For the electrolyte MgSO4, however, each ion is doubly-charged, leading to an ionic strength that is four times higher than an equivalent concentration of sodium chloride:
Generally multivalent ions contribute strongly to the ionic strength.
Calculation example
As a more complex example, the ionic strength of a mixed solution 0.050 M in Na2SO4 and 0.020 M in KCl is:
Non-ideal solutions
Because in non-ideal solutions volumes are no longer strictly additive it is often preferable to work with molality b (mol/kg of H2O) rather than molarity c (mol/L). In that case, molal ionic strength is defined as:
in which
i = ion identification number
z = charge of ion
b = molality (mol solute per Kg solvent)
Importance
The ionic strength plays a central role in the Debye–Hückel theory that describes the strong deviations from id
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https://en.wikipedia.org/wiki/Flow%20%28mathematics%29
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In mathematics, a flow formalizes the idea of the motion of particles in a fluid. Flows are ubiquitous in science, including engineering and physics. The notion of flow is basic to the study of ordinary differential equations. Informally, a flow may be viewed as a continuous motion of points over time. More formally, a flow is a group action of the real numbers on a set.
The idea of a vector flow, that is, the flow determined by a vector field, occurs in the areas of differential topology, Riemannian geometry and Lie groups. Specific examples of vector flows include the geodesic flow, the Hamiltonian flow, the Ricci flow, the mean curvature flow, and Anosov flows. Flows may also be defined for systems of random variables and stochastic processes, and occur in the study of ergodic dynamical systems. The most celebrated of these is perhaps the Bernoulli flow.
Formal definition
A flow on a set is a group action of the additive group of real numbers on . More explicitly, a flow is a mapping
such that, for all and all real numbers and ,
It is customary to write instead of , so that the equations above can be expressed as (the identity function) and (group law). Then, for all the mapping is a bijection with inverse This follows from the above definition, and the real parameter may be taken as a generalized functional power, as in function iteration.
Flows are usually required to be compatible with structures furnished on the set . In particular, if is equipped with a topology, then is usually required to be continuous. If is equipped with a differentiable structure, then is usually required to be differentiable. In these cases the flow forms a one-parameter group of homeomorphisms and diffeomorphisms, respectively.
In certain situations one might also consider s, which are defined only in some subset
called the of . This is often the case with the flows of vector fields.
Alternative notations
It is very common in many fields, including engi
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https://en.wikipedia.org/wiki/Unconditional%20convergence
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In mathematics, specifically functional analysis, a series is unconditionally convergent if all reorderings of the series converge to the same value. In contrast, a series is conditionally convergent if it converges but different orderings do not all converge to that same value. Unconditional convergence is equivalent to absolute convergence in finite-dimensional vector spaces, but is a weaker property in infinite dimensions.
Definition
Let be a topological vector space. Let be an index set and for all
The series is called unconditionally convergent to if
the indexing set is countable, and
for every permutation (bijection) of the following relation holds:
Alternative definition
Unconditional convergence is often defined in an equivalent way: A series is unconditionally convergent if for every sequence with the series
converges.
If is a Banach space, every absolutely convergent series is unconditionally convergent, but the converse implication does not hold in general. Indeed, if is an infinite-dimensional Banach space, then by Dvoretzky–Rogers theorem there always exists an unconditionally convergent series in this space that is not absolutely convergent. However when by the Riemann series theorem, the series is unconditionally convergent if and only if it is absolutely convergent.
See also
References
Ch. Heil: A Basis Theory Primer
Convergence (mathematics)
Mathematical analysis
Mathematical series
Summability theory
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https://en.wikipedia.org/wiki/Water%20Environment%20Federation
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The Water Environment Federation (WEF) is a not-for-profit technical and educational organization of more than 34,000 individual members and 75 Member Associations (MAs) representing water quality professionals around the world. WEF, which was formerly known as the Federation of Sewage Works Associations and later as the Water Pollution Control Federation, and its members have protected public health and the environment since 1928. As a global water sector leader, the organization's mission is to connect water professionals; enrich the expertise of water professionals; increase the awareness of the impact and value of water; and provide a platform for water sector innovation. WEF members include experts and specialists in the fields of:
environmental engineering
industrial wastewater treatment
sewage treatment and sewage sludge treatment
stormwater management
water quality analysis and planning
and related disciplines.
WEF is headquartered in Alexandria, Virginia, United States.
Publications and Conferences
In addition to books, technical reports, and conferences proceedings, WEF publishes the peer-reviewed journal, Water Environment Research, and the magazine, Water Environment Technology. WEF sponsors local and national speciality meetings, as well as the world's largest annual water conference: WEFTEC - Water Environment Federation Technical Exposition and Conference.
Awards
To recognize individuals and groups in a number of areas, WEF sponsors awards in the categories of: Published Papers; Operational and Design Excellence; Education; Individual Service and Contribution; Fellows; Organization and Association Recognition; National Municipal Stormwater and Green Infrastructure, as well as Committee Chair Service Appreciation.
See also
National Association of Clean Water Agencies (NACWA) - U.S. local government sewage treatment agencies
Water supply and sanitation in the United States
References
External links
American engineering organizations
Environme
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https://en.wikipedia.org/wiki/Crystal%20Ball%20function
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The Crystal Ball function, named after the Crystal Ball Collaboration (hence the capitalized initial letters), is a probability density function commonly used to model various lossy processes in high-energy physics. It consists of a Gaussian core portion and a power-law low-end tail, below a certain threshold. The function itself and its first derivative are both continuous.
The Crystal Ball function is given by:
where
,
,
,
,
.
(Skwarnicki 1986) is a normalization factor and , , and are parameters which are fitted with the data. erf is the error function.
External links
J. E. Gaiser, Appendix-F Charmonium Spectroscopy from Radiative Decays of the J/Psi and Psi-Prime, Ph.D. Thesis, SLAC-R-255 (1982). (This is a 205-page document in .pdf form – the function is defined on p. 178.)
M. J. Oreglia, A Study of the Reactions psi prime --> gamma gamma psi, Ph.D. Thesis, SLAC-R-236 (1980), Appendix D.
T. Skwarnicki, A study of the radiative CASCADE transitions between the Upsilon-Prime and Upsilon resonances, Ph.D Thesis, DESY F31-86-02(1986), Appendix E.
Functions and mappings
Continuous distributions
Experimental particle physics
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https://en.wikipedia.org/wiki/Theil%20index
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The Theil index is a statistic primarily used to measure economic inequality and other economic phenomena, though it has also been used to measure racial segregation.
The Theil index TT is the same as redundancy in information theory which is the maximum possible entropy of the data minus the observed entropy. It is a special case of the generalized entropy index. It can be viewed as a measure of redundancy, lack of diversity, isolation, segregation, inequality, non-randomness, and compressibility. It was proposed by a Dutch econometrician Henri Theil (1924-2000) at the Erasmus University Rotterdam.
Henri Theil himself said (1967): "The (Theil) index can be interpreted as the expected information content of the indirect message which transforms the population shares as prior probabilities into the income shares as posterior probabilities."
Amartya Sen noted, "But the fact remains that the Theil index is an arbitrary formula, and the average of the logarithms of the reciprocals of income shares weighted by income is not a measure that is exactly overflowing with intuitive sense."
Formula
For a population of N "agents" each with characteristic x, the situation may be represented by the list xi (i = 1,...,N) where xi is the characteristic of agent i. For example, if the characteristic is income, then xi is the income of agent i.
The Theil T index is defined as
and the Theil L index is defined as
where is the mean income:
Theil-L is an income-distribution's dis-entropy per person, measured with respect to maximum entropy (...which is achieved with complete equality).
(In an alternative interpretation of it, Theil-L is the natural-logarithm of the geometric-mean of the ratio: (mean income)/(income i), over all the incomes. The related Atkinson(1) is just 1 minus the geometric-mean of (income i)/(mean income),over the income distribution.)
Because a transfer between a larger income & a smaller one will change the smaller income's ratio more than it chan
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https://en.wikipedia.org/wiki/Radisys
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Radisys Corporation is an American technology company located in Hillsboro, Oregon, United States that makes technology used by telecommunications companies in mobile networks. Founded in 1987 in Oregon by former employees of Intel, the company went public in 1995. The company's products are used in mobile network applications such as small cell radio access networks, wireless core network elements, deep packet inspection and policy management equipment; conferencing, and media services including voice, video and data. In 2015, the first-quarter revenues of Radisys totaled $48.7 million, and approximately employed 700 people. Arun Bhikshesvaran is the company's chief executive officer.
On 30 June 2018, multinational conglomerate Reliance Industries acquired Radisys for $74 million.
It now operates as an independent subsidiary.
History
Radisys was founded in 1987 as Radix Microsystems in Beaverton, Oregon, by former Intel engineers Dave Budde and Glen Myers. The first investors were employees who put up $50,000 each, with Tektronix later investing additional funds into the company. Originally located in space leased from Sequent Computer Systems, by 1994 the company had grown to annual sales of $20 million. The company's products were computers used in end products such as automated teller machines to paint mixers. On October 20, 1995, the company became a publicly traded company when it held an initial public offering (IPO). The IPO raised $19.6 million for Radisys after selling 2.7 million shares at $12 per share.
In 1996, the company moved its headquarters to a new campus in Hillsboro, and at that time sales reached $80 million and the company had a profit of $9.6 million that year with 175 employees. Company co-founder Dave Budde left the company in 1997, with company revenues at $81 million annually at that time. The company grew in part by acquisitions such as Sonitech International in 1997, part of IBM's Open Computing Platform unit and Texas Micro in 1999
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https://en.wikipedia.org/wiki/Artificial%20plants
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Artificial plants are imitations of natural plants used for commercial or residential decoration. They are sometimes made for scientific purposes (the collection of glass flowers at Harvard University, for example, illustrates the flora of the United States). Artificial plants vary widely from mass-produced varieties that are distinguishable from real plants by casual observation to highly detailed botanical or artistic specimens.
Materials used in their manufacture have included painted linen and shavings of stained horn in ancient Egypt, gold and silver in ancient Rome, rice-paper in China, silkworm cocoons in Italy, colored feathers in South America, and wax and tinted shells. Modern techniques involve carved or formed soap, nylon netting stretched over wire frames, ground clay, and mass-produced injection plastic mouldings. Polyester has been the main material for manufacturing artificial flowers since the 1970s. Most artificial flowers in the market nowadays are made of polyester fabric.
Production
The industry is now highly specialized with several different manufacturing processes. Hundreds of artificial flower factories in the Pearl River delta area of Guangdong province in China have been built since the early 1980s. Thousands of 40-foot containers of polyester flowers and plants are exported to many countries every year.
Polyester and paper
Five main processes may be distinguished:
The first step consists of putting the polyester fabric in gelatine in order to stiffen it.
The second consists of cutting up the various polyester fabrics and materials employed into shapes suitable for forming the leaves, petals, etc.; this may be done with scissors, but is more often done with stamps that can cut through a dozen or more thicknesses at one blow.
Next, the veins of the leaves are impressed by means of silk screen printing with a dye, and the petals are given their natural rounded forms by goffering irons of various shapes.
The next step is to assemble
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https://en.wikipedia.org/wiki/Virtual%20Console
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The Virtual Console is a line of downloadable video games for Nintendo's Wii and Wii U home video game consoles and the Nintendo 3DS family of systems.
The Virtual Console lineup consisted of titles originally released on past home and handheld consoles. These titles were run in their original forms through software emulation (excluding GBA titles on the 3DS and Wii on Wii U), therefore remaining mostly unaltered, and could be purchased from the Wii Shop Channel or Nintendo eShop for between 500 and 1200 Wii Points. They could also be purchased using real currency for $2.99 and $9.99 (3DS) and $4.99 and $9.99 (Wii U), depending on the system, rarity, and/or demand. Virtual Console's library of past games consisted of titles originating from the Nintendo Entertainment System, Super Nintendo Entertainment System, Game Boy, Game Boy Color, Nintendo 64, Game Boy Advance, and Nintendo DS, as well as Sega's Master System, Genesis/Mega Drive and Game Gear, NEC's TurboGrafx-16, and SNK's Neo Geo AES. The service for the Wii also included games for platforms that were known only in select regions, such as the Commodore 64 (Europe and North America) and Microsoft's and ASCII's MSX (Japan), as well as Virtual Console Arcade, which allowed players to download video arcade games. Virtual Console titles have been downloaded over ten million times. The distribution of past games through the Virtual Console is one of Nintendo's reasons for opposing software piracy of old console games.
On January 30, 2019, the Virtual Console service was discontinued on the Wii, following the shutdown of the Wii Shop Channel.
On March 27, 2023, the Virtual Console service was discontinued on the Wii U and Nintendo 3DS. Purchased titles remain playable.
List of Virtual Console games
Japan
There were 38 Famicom, Super Famicom, Nintendo 64, Sega Mega Drive, and PC Engine games available at launch on the Wii Virtual Console for the Japanese region. The Nintendo 3DS Virtual Console launched with 7
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https://en.wikipedia.org/wiki/Scabbling
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Scabbling—also called scappling—is the process of reducing stone or concrete. In masonry, it refers to shaping a stone to a rough square by use of an axe or hammer. In Kent, rag-stone masons call this "knobbling". It was similarly used to shape grindstones.
In modern construction, scabbling is a mechanical process of removing a thin layer of concrete from a structure, typically achieved by compressed air powered machines. A typical scabbling machine uses several heads, each with several carbide or steel tips that peck at the concrete. It operates by pounding a number of tipped rods down onto the concrete surface in rapid succession. It takes several passes with the machine to achieve the desired depth.
Scabbling is used to remove road markings, surface contamination (used in the nuclear industry), to add a decorative or textured pattern to concrete, or to prepare a concrete surface prior to the installation of grout.
Scarifying machines with flails attached to a drum cage are sometimes referred to as rotary scabblers. These walk behind machines are also referred to as concrete planers.
See also
References
Masonry
Stonemasonry
Construction
Articles containing video clips
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https://en.wikipedia.org/wiki/Network%20browser
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A network browser is a tool used to browse a computer network. An example of this is My Network Places (or Network Neighborhood in earlier versions of Microsoft Windows). An actual program called Network Browser is offered in Mac OS 9.
See also
Browser service
Computer networking
References
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https://en.wikipedia.org/wiki/My%20Network%20Places
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My Network Places (formerly Network Neighborhood) is the network browser feature in Windows Explorer. It was first introduced in Windows 95 and Windows NT 4.0 and was renamed My Network Places in Windows 2000 and later, before being replaced in Windows Vista.
My Network Places maintains an automatically updated history of computers which the user has accessed before, by default placed in a folder called , found in the user's user profile. This default location can be changed by modifying the pair of registry entries found under the registry keys and . The feature also allows enumerating all computers on the local network that support the Server Message Block (SMB) protocol and are open to discovery.
In a workgroup of fewer than 32 computers, the list of network destinations in My Network Places is generated by one of the computers on the network, which has been designated "Browse Master" (sometimes called "master browser"). The Browse Master is elected by system strength. Sometimes when similar systems are connected to a network, there might be a conflict between Browse Masters with unexpected consequences, such as the disappearance of the list altogether or some system becoming unreachable. A system can be forced to decline Browse Master status by disabling the Browser service and rebooting. In a workgroup of 32 computers or more, the shortcuts are created automatically when the user opens a shared network resource, such as a printer or shared folder.
Starting with Windows Vista, My Network Places is removed in favor of an integrated "Network" node in Windows Explorer. This node can only enumerate network computers but can do so via WS-Discovery and UPnP protocols, in addition to SMB.
See also
Special folder
References
External links
SecurityFriday: Hazard of "My Network Places" on Windows XP
Computer Browser and common issues
Browsers
Windows communication and services
File system directories
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https://en.wikipedia.org/wiki/Molecular%20gastronomy
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Molecular gastronomy is the scientific approach of cuisine from primarily the perspective of chemistry. The composition (molecular structure), properties (mass, viscosity, etc) and transformations (chemical reactions, reactant products) of an ingredient are addressed and utilized in the preparation and appreciation of the ingested products. It is a branch of food science that approaches the preparation and enjoyment of nutrition from the perspective of a scientist at the scale of atoms, molecules, and mixtures.
Nicholas Kurti, Hungarian physicist, and Hervé This, at the INRA in France, coined "Molecular and Physical Gastronomy" in 1988.
Examples
Eponymous recipes
New dishes named after famous scientists include:
Gibbs – infusing vanilla pods in egg white with sugar, adding olive oil and then microwave cooking. Named after physicist Josiah Willard Gibbs (1839–1903).
Vauquelin – using orange juice or cranberry juice with added sugar when whipping eggs to increase the viscosity and to stabilize the foam, and then microwave cooking. Named after Nicolas Vauquelin (1763–1829), one of Lavoisier's teachers.
Baumé – soaking a whole egg for a month in alcohol to create a coagulated egg. Named after the French chemist Antoine Baumé (1728–1804).
History
There are many branches of food science that study different aspects of food, such as safety, microbiology, preservation, chemistry, engineering, and physics. Until the advent of molecular gastronomy, there was no branch dedicated to studying the chemical processes of cooking in the home and in restaurants. Food science has primarily been concerned with industrial food production and, while the disciplines may overlap, they are considered separate areas of investigation.
The creation of the discipline of molecular gastronomy was intended to bring together what had previously been fragmented and isolated investigations into the chemical and physical processes of cooking into an organized discipline within food science, to
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https://en.wikipedia.org/wiki/Lanthanum%20gallium%20silicate
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Lanthanum gallium silicate (referred to as LGS in this article), also known as langasite, has a chemical formula of the form A3BC3D2O14, where A, B, C and D indicate particular cation sites. A is a decahedral (Thomson cube) site coordinated by 8 oxygen atoms. B is octahedral site coordinated by 6 oxygen atoms, and C and D are tetrahedral sites coordinated by 4 oxygen atoms. In this material, lanthanum occupied the A-sites, gallium the B, C and half of D-sites, and, silicon the other half of D-sites.
LGS is a piezoelectric material, with no phase transitions up to its melting point of 1470 °C. Single crystal LGS can be grown via the Czochralski method, in which crystallization is initiated on a rotating seed crystal lowered into the melt followed by pulling from the melt. The growth atmosphere is usually argon or nitrogen with up to 5% of oxygen. The use of oxygen in the growth environment is reported to suppress gallium loss from the melt; however, too high an oxygen level can lead to platinum (crucible material used for the melt) dissolution in the melt. The growth of LGS is primarily along the z direction. Currently the 3-inch (76 mm) langasite boules produced commercially have growth rates of 1.5 to 5 mm/h. The quality of the crystals tends to improve as the growth rate is reduced.
See also
Ceramic
lanthanum gallium tantalum oxide, langatite (CAS RN 83381-05-9) La6Ga11TaO28 (i.e., La3Ga5.5Ta00.5O14)
References
External links
Properties of a langasite crystal
Lanthanum compounds
Gallium compounds
Silicates
Piezoelectric materials
Ceramic materials
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https://en.wikipedia.org/wiki/Floppy-disk%20controller
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A floppy-disk controller (FDC) has evolved from a discrete set of components on one or more circuit boards to a special-purpose integrated circuit (IC or "chip") or a component thereof. An FDC directs and controls reading from and writing to a computer's floppy disk drive (FDD). The FDC is responsible for reading data presented from the host computer and converting it to the drive's on-disk format using one of a number of encoding schemes, like FM encoding (single density) or MFM encoding (double density), and reading those formats and returning it to its original binary values.
Depending on the platform, data transfers between the controller and host computer would be controlled by the computer's own microprocessor, or an inexpensive dedicated microprocessor like the MOS 6507 or Zilog Z80. Early controllers required additional circuitry to perform specific tasks like providing clock signals and setting various options. Later designs included more of this functionality on the controller and reduced the complexity of the external circuitry; single-chip solutions were common by the later 1980s.
By the 1990s, the floppy disk was increasingly giving way to hard drives, which required similar controllers. In these systems, the controller also often combined a microcontroller to handle data transfer over standardized connectors like SCSI and IDE that could be used with any computer. In more modern systems, the FDC, if present at all, is typically part of the many functions provided by a single super I/O chip.
History
The first floppy disk drive controller (FDC) like the first floppy disk drive (the IBM 23FD) shipped in 1971 as a component in the IBM 2385 Storage Control Unit for the IBM 2305 fixed head disk drive, and of the System 370 Models 155 and 165. The IBM 3830 Storage Control Unit, a contemporaneous and quite similar controller, uses its internal processor to control a 23FD. The resultant FDC is a simple implementation in IBMs’ MST hybrid circuits on a few pr
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https://en.wikipedia.org/wiki/DO-178B
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DO-178B, Software Considerations in Airborne Systems and Equipment Certification is a guideline dealing with the safety of safety-critical software used in certain airborne systems. It was jointly developed by the safety-critical working group RTCA SC-167 of the Radio Technical Commission for Aeronautics (RTCA) and WG-12 of the European Organisation for Civil Aviation Equipment (EUROCAE). RTCA published the document as RTCA/DO-178B, while EUROCAE published the document as ED-12B. Although technically a guideline, it was a de facto standard for developing avionics software systems until it was replaced in 2012 by DO-178C.
The Federal Aviation Administration (FAA) applies DO-178B as the document it uses for guidance to determine if the software will perform reliably in an airborne environment, when specified by the Technical Standard Order (TSO) for which certification is sought. In the United States, the introduction of TSOs into the airworthiness certification process, and by extension DO-178B, is explicitly established in Title 14: Aeronautics and Space of the Code of Federal Regulations (CFR), also known as the Federal Aviation Regulations, Part 21, Subpart O.
Software level
The Software Level, also termed the Design Assurance Level (DAL) or Item Development Assurance Level (IDAL) as defined in ARP4754 (DO-178C only mentions IDAL as synonymous with Software Level), is determined from the safety assessment process and hazard analysis by examining the effects of a failure condition in the system. The failure conditions are categorized by their effects on the aircraft, crew, and passengers.
Catastrophic – Failure may cause a crash. Error or loss of critical function required to safely fly and land aircraft.
Hazardous – Failure has a large negative impact on safety or performance, or reduces the ability of the crew to operate the aircraft due to physical distress or a higher workload, or causes serious or fatal injuries among the passengers. (Safety-significant
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https://en.wikipedia.org/wiki/Erd%C5%91s%E2%80%93Bacon%20number
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A person's Erdős–Bacon number is the sum of one's Erdős number—which measures the "collaborative distance" in authoring academic papers between that person and Hungarian mathematician Paul Erdős—and one's Bacon number—which represents the number of links, through roles in films, by which the person is separated from American actor Kevin Bacon. The lower the number, the closer a person is to Erdős and Bacon, which reflects a small world phenomenon in academia and entertainment.
To have a defined Erdős–Bacon number, it is necessary to have both appeared in a film and co-authored an academic paper, although this in and of itself is not sufficient as one's co-authors must have a known chain leading to Paul Erdős, and one's film must have actors eventually leading to Kevin Bacon.
Academic scientists
Mathematician Daniel Kleitman has an Erdős–Bacon number of 3. He co-authored papers with Erdős and has a Bacon number of 2 via Minnie Driver in Good Will Hunting; Driver and Bacon appeared together in Sleepers.
Like Kleitman, mathematician Bruce Reznick has co-authored a paper with Erdős and has a Bacon number of 2, via Roddy McDowall in the film Pretty Maids All in a Row, giving him an Erdős–Bacon number of 3 as well.
Physicist Nicholas Metropolis has an Erdős number of 2, and also a Bacon number of 2, giving him an Erdős–Bacon number of 4.
Metropolis and Richard Feynman both worked on the Manhattan Project at Los Alamos Laboratory. Via Metropolis, Feynman has an Erdős number of 3 and, from having appeared in the film Anti-Clock alongside Tony Tang, Feynman also has a Bacon number of 3. Richard Feynman thus has an Erdős–Bacon number of 6.
Theoretical physicist Stephen Hawking has an Erdős–Bacon number of 6: his Bacon number of 2 (via his appearance alongside John Cleese in Monty Python Live (Mostly), who acted alongside Kevin Bacon in The Big Picture) is lower than his Erdős number of 4.
Similarly to Stephen Hawking, scientist Carl Sagan has an Erdős–Bacon number of 6
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https://en.wikipedia.org/wiki/Calie%20Pistorius
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Carl Wilhelm Irene ("Calie") Pistorius (born 9 August 1958) is a South African academic who is a former Vice-Chancellor of the University of Hull, Kingston upon Hull, United Kingdom. He announced, on 1 August 2016, that he would be stepping down from this role at the end of January 2017. His successor at Hull was Professor Susan Lea.
Education
Pistorius obtained the degree B.Sc (Eng) (cum laude) in electronic engineering from the University of Pretoria in 1979 and the degree B.Eng (Hons) (cum laude) in electronic engineering from the same university in 1981. He obtained a M.S. degree in electrical engineering from the Ohio State University in the U.S. in 1984, a Ph.D. degree in electrical engineering also from the Ohio State University in 1986, and a Master's degree in management (M.B.A.) from the MIT Sloan School of Management in 1994.
Academic career
Pistorius is a consultant to industry and government on issues relating to strategy, management of technology, technological innovation, competitiveness and national technological policy. He is also a member of the National Advisory Council on Innovation in South Africa.
Pistorius has published widely both nationally and internationally and has 107 academic publications to his credit. He has received numerous awards and prizes including the prize for the best Ph.D. dissertation from the ElectroScience Laboratory at the Ohio State University, the President's Award from the National Research Foundation and the Bill Venter Prize for outstanding contributions to research published in book form by university personnel in South Africa.
At the university, Pistorius was head of the Department of Electronic and Electrical Engineering for five years, Director of the Institute for Technological Innovation for four years, Director of Information Technology for two years and Dean of the Faculty for one and a half years.
On 25 February 2009, it was announced that Pistorius would be stepping down from his position as Vice-Chan
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https://en.wikipedia.org/wiki/Cyberfeminism
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Cyberfeminism is a feminist approach which foregrounds the relationship between cyberspace, the Internet, and technology. It can be used to refer to a philosophy, methodology or community. The term was coined in the early 1990s to describe the work of feminists interested in theorizing, critiquing, exploring and re-making the Internet, cyberspace and new-media technologies in general. The foundational catalyst for the formation of cyberfeminist thought is attributed to Donna Haraway's "A Cyborg Manifesto", third wave feminism, post-structuralist feminism, riot grrrl culture and the feminist critique of the alleged erasure of women within discussions of technology.
Definition
Cyberfeminism is a sort of alliance that wants to defy any sort of boundaries of identity and definition and rather be truly postmodern in its potential for radical openness. This is seen with the 1997 Old Boys Network's 100 anti-theses which lists the 100 ways "cyberfeminism is not." Cornelia Sollfrank from the Old Boys Network states that:Cyberfeminism is a myth. A myth is a story of unidentifiable origin, or of different origins. A myth is based on one central story which is retold over and over in different variations. A myth denies one history as well as one truth, and implies a search for truth in the spaces, in the differences between the different stories. Speaking about Cyberfeminism as a myth, is not intended to mystify it, it simply indicates that Cyberfeminism only exists in plural.Mia Consalvo defines cyberfeminism as:
a label for women—especially young women who might not even want to align with feminism's history—not just to consume new technologies but to actively participate in their making;
a critical engagement with new technologies and their entanglement with power structures and systemic oppression.
The dominant cyberfeminist perspective takes a utopian view of cyberspace and the Internet as a means of freedom from social constructs such as gender, sex difference and ra
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https://en.wikipedia.org/wiki/Digital%20River
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Digital River is a private company that provides global e-commerce, payments and marketing services. In 2013, Digital River processed more than $30 billion in online transactions. Digital River is headquartered in Minnetonka, Minnesota.
Company operations
Digital River has a history of acquiring other companies in the e-commerce (including digital software delivery) industry.
Notable acquisitions include:
Simtel (1999)
CCNow (2002)
SWREG (2005)
eSellerate (2006)
Freemerchant.com (discontinued 15 January 2008)
THINK Subscription (2008)
Journey Education Marketing (2010)
Fatfoogoo (2010)
Divestitures
CCNow (sold to Snorrason Holdings 2012)
Journey Education Marketing (2013)
Security failings
A security breach in 2010 resulted in nearly 200,000 customers' data being stolen. A lawsuit followed by Digital River.
In October 2017, the websites for Equifax, and for TransUnion's Central American division were reported to have been redirecting visitors to websites that attempted drive-by downloads of malware disguised as Adobe Flash updates. The attack had been performed by hijacking third-party analytics JavaScript from FireClick. Digital River decommissioned the FireClick platform and released the domain in 2016, so the domain was not owned by Digital River at the time of the attack.
Management history
Joel Ronning was CEO from the company's founding until stepping down in November 2012. In June 2013, Ronning was ranked as the most overpaid CEO at a public company in Minnesota.
In February 2013, Dave Dobson was named CEO.
In July 2018, Adam Coyle was named CEO with Mr. Dobson becoming Vice Chairman of the Board. Mr. Coyle had previously been on the board since 2015 and worked as an executive partner with Digital River's private equity owner, Siris Capital.
In January 2020, Christopher Bernander was named CFO.
References
External links
DigitalRiver.com
Software companies based in Minnesota
Companies based in Minnetonka, Minnesota
American companies established
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https://en.wikipedia.org/wiki/Multi-agent%20planning
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In computer science multi-agent planning involves coordinating the resources and activities of multiple agents.
NASA says, "multiagent planning is concerned with planning by (and for) multiple agents. It can involve agents planning for a common goal, an agent coordinating the plans (plan merging) or planning of others, or agents refining their own plans while negotiating over tasks or resources. The topic also involves how agents can do this in real time while executing plans (distributed continual planning). Multiagent scheduling differs from multiagent planning the same way planning and scheduling differ: in scheduling often the tasks that need to be performed are already decided, and in practice, scheduling tends to focus on algorithms for specific problem domains".
See also
Automated planning and scheduling
Distributed artificial intelligence
Cooperative distributed problem solving and Coordination
Multi-agent systems and Software agent and Self-organization
Multi-agent reinforcement learning
Task Analysis, Environment Modeling, and Simulation (TAEMS or TÆMS)
References
Further reading
Durfee's (1999) chapter on Distributed Problem Solving and Planning
desJardins et al. (1999). A Survey of Research in Distributed, Continual Planning.
.
See Chapter 2; downloadable free online.
External links
A tutorial on planning in multiagent systems
Multi-agent systems
Automated planning and scheduling
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https://en.wikipedia.org/wiki/History%20of%20the%20Actor%20model
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In computer science, the Actor model, first published in 1973, is a mathematical model of concurrent computation.
Event orderings versus global state
A fundamental challenge in defining the Actor model is that it did not provide for global states so that a computational step could not be defined as going from one global state to the next global state as had been done in all previous models of computation.
In 1963 in the field of Artificial Intelligence, John McCarthy introduced situation variables in logic in the Situational Calculus. In McCarthy and Hayes 1969, a situation is defined as "the complete state of the universe at an instant of time." In this respect, the situations of McCarthy are not suitable for use in the Actor model since it has no global states.
From the definition of an Actor, it can be seen that numerous events take place: local decisions, creating Actors, sending messages, receiving messages, and designating how to respond to the next message received. Partial orderings on such events have been axiomatized in the Actor model and their relationship to physics explored (see Actor model theory).
Relationship to physics
According to Hewitt (2006), the Actor model is based on physics in contrast with other models of computation that were based on mathematical logic, set theory, algebra, etc. Physics influenced the Actor model in many ways, especially quantum physics and relativistic physics. One issue is what can be observed about Actor systems. The question does not have an obvious answer because it poses both theoretical and observational challenges similar to those that had arisen in constructing the foundations of quantum physics. In concrete terms for Actor systems, typically we cannot observe the details by which the arrival order of messages for an Actor is determined (see Indeterminacy in concurrent computation). Attempting to do so affects the results and can even push the indeterminacy elsewhere. e.g., see metastability in electronics.
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https://en.wikipedia.org/wiki/Sphericity
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Sphericity is a measure of how closely the shape of an object resembles that of a perfect sphere. For example, the sphericity of the balls inside a ball bearing determines the quality of the bearing, such as the load it can bear or the speed at which it can turn without failing. Sphericity is a specific example of a compactness measure of a shape. Defined by Wadell in 1935, the sphericity, , of an object is the ratio of the surface area of a sphere with the same volume to the object's surface area:
where is volume of the object and is the surface area. The sphericity of a sphere is unity by definition and, by the isoperimetric inequality, any shape which is not a sphere will have sphericity less than 1.
Sphericity applies in three dimensions; its analogue in two dimensions, such as the cross sectional circles along a cylindrical object such as a shaft, is called roundness.
Ellipsoidal objects
The sphericity, , of an oblate spheroid (similar to the shape of the planet Earth) is:
where a and b are the semi-major and semi-minor axes respectively.
Derivation
Hakon Wadell defined sphericity as the surface area of a sphere of the same volume as the particle divided by the actual surface area of the particle.
First we need to write surface area of the sphere, in terms of the volume of the object being measured,
therefore
hence we define as:
Sphericity of common objects
See also
Equivalent spherical diameter
Flattening
Isoperimetric ratio
Rounding (sediment)
Roundness
Willmore energy
References
External links
Grain Morphology: Roundness, Surface Features, and Sphericity of Grains
Geometric measurement
Spheres
Metrology
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https://en.wikipedia.org/wiki/Open%20Enterprise%20Server
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Open Enterprise Server (OES) is a server operating system published by Novell in March 2005 to succeed their NetWare product.
Unlike NetWare, Novell OES is a Linux distribution—specifically, one based on SUSE Linux Enterprise Server. The first major release of Open Enterprise Server (OES 1) could run either with a Linux kernel (with a NetWare compatibility layer) or Novell's NetWare kernel (with a Linux compatibility layer). Novell discontinued the NetWare kernel prior to the release of OES 2, but NetWare 6.5 SP7, and later SP8 can run as a paravirtualized guest inside the Xen hypervisor (Officially supported until 7 March 2012, Novell self-supported until 7 March 2015).
OES 1 and OES 2
Novell released OES 1, the first version of OES, on 25 March 2005. Since some users wanted backward compatibility with NetWare, Novell offered two installation options: OES-NetWare and OES-Linux. These are two different operating systems with different kernels and different userlands.
OES-NetWare is NetWare v6.5 equipped with NetWare Loadable Modules for various Novell services (such as NetWare Core Protocol, Novell eDirectory, Novell Storage Services, and iPrint) and open-source software (such as OpenSSH, Apache Tomcat, and the Apache HTTP Server).
OES-Linux is based on the SUSE Linux Enterprise Server (SLES) with added NetWare services ported to the Linux kernel: e.g. the NetWare Core Protocol, Novell eDirectory, Novell Storage Services, and iPrint.
Novell released OES 2, the second version of OES, on 12 October 2007. It was the first SLES-Linux-kernel-only OES, but it retained the OES-NetWare operating system option, as NetWare 6.5 SP7 can run as a paravirtualized guest inside the Xen hypervisor. The SLES base of the OES 2 was later updated to SLES 10 SP1.
Features introduced in OES 2 include:
32-bit system or 64-bit system supporting 64 bit and 32 bit applications
Hardware virtualization
Dynamic Storage Technology, which provides Novell Shadow Volumes
Windows domain se
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https://en.wikipedia.org/wiki/Normal%20scheme
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In algebraic geometry, an algebraic variety or scheme X is normal if it is normal at every point, meaning that the local ring at the point is an integrally closed domain. An affine variety X (understood to be irreducible) is normal if and only if the ring O(X) of regular functions on X is an integrally closed domain. A variety X over a field is normal if and only if every finite birational morphism from any variety Y to X is an isomorphism.
Normal varieties were introduced by .
Geometric and algebraic interpretations of normality
A morphism of varieties is finite if the inverse image of every point is finite and the morphism is proper. A morphism of varieties
is birational if it restricts to an isomorphism between dense open subsets. So, for example, the cuspidal cubic curve X in the affine plane A2 defined by x2 = y3 is not normal, because there is a finite birational morphism A1 → X
(namely, t maps to (t3, t2)) which is not an isomorphism. By contrast, the affine line A1 is normal: it cannot be simplified any further by finite birational morphisms.
A normal complex variety X has the property, when viewed as a stratified space using the classical topology, that every link is connected. Equivalently, every complex point x has arbitrarily small neighborhoods U such that U minus
the singular set of X is connected. For example, it follows that the nodal cubic curve X in the figure, defined by x2 = y2(y + 1), is not normal. This also follows from the definition of normality, since there is a finite birational morphism from A1 to X which is not an isomorphism; it sends two points of A1 to the same point in X.
More generally, a scheme X is normal if each of its local rings
OX,x
is an integrally closed domain. That is, each of these rings is an integral domain R, and every ring S with R ⊆ S ⊆ Frac(R) such that S is finitely generated as an R-module is equal to R. (Here Frac(R) denotes the field of fractions of R.) This is a direct translation, in terms of local rin
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https://en.wikipedia.org/wiki/Feature%20connector
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The feature connector was an internal connector found mostly in some older ISA, VESA Local Bus, and PCI graphics cards, but also on some early AGP ones. It was intended for use by devices which needed to exchange large amounts of data with the graphics card without hogging a computer system's CPU or data bus, such as TV tuner cards, video capture cards, MPEG video decoders (e.g. RealMagic), and first generation 3D graphic accelerator cards. Early examples include the IBM EGA video adapter.
Several standards existed for feature connectors, depending on the bus and graphics card type. Most of them were simply an 8, 16 or 32-bit wide internal connector, transferring data between the graphics card and another device, bypassing the system's CPU and memory completely.
Their speeds often far exceeded the speed of normal ISA or even early PCI buses, e.g. 40 MByte/s for a standard ISA-based SVGA, up to 150 MByte/s for a VESA-based or PCI-based one, while the standard 16 bit ISA bus ran at ~5.3 MByte/s and the VESA bus at up to 160 MByte/s bandwidth. The Feature connector bandwidths were far beyond the capabilities of e.g. a 386, 486 and barely handled by an early Pentium.
Depending on the implementation, it could be uni or bi-directional, and carry analog color information as well as data. Unlike analog overlay devices however, a feature connector carried mainly data and essentially allowed an expansion card to access the graphics card Video RAM directly, although directing this data stream to the system's CPU and RAM was not always possible, limiting its usefulness mainly to display purposes.
Although its use rapidly declined after the introduction of the faster AGP internal bus, it was, at its time, the only feasible way to connect certain types of graphics-intensive devices to an average computing system without exceeding the available CPU power and memory bandwidth, and without the disadvantages and limitations of a purely analog overlay.
The idea of accessing a vi
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https://en.wikipedia.org/wiki/DNP3
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Distributed Network Protocol 3 (DNP3) is a set of communications protocols used between components in process automation systems. Its main use is in utilities such as electric and water companies. Usage in other industries is not common. It was developed for communications between various types of data acquisition and control equipment. It plays a crucial role in SCADA systems, where it is used by SCADA Master Stations (a.k.a. Control Centers), Remote Terminal Units (RTUs), and Intelligent Electronic Devices (IEDs). It is primarily used for communications between a master station and RTUs or IEDs. ICCP, the Inter-Control Center Communications Protocol (a part of IEC 60870-6), is used for inter-master station communications. Competing standards include the older Modbus protocol and the newer IEC 61850 protocol.
History
While IEC 60870-5 was still under development and had not been standardized, there was a need to create a standard that would allow interoperability between various vendors' SCADA components for the electrical grid. Thus, in 1993, GE-Harris Canada (formerly known as Westronic) used the partially completed IEC 60870-5 protocol specifications as the basis for an open and immediately implementable protocol that specifically catered to North American requirements. The protocol is designed to allow reliable communications in the adverse environments that electric utility automation systems are subjected to, being specifically designed to overcome distortion induced by electromagnetic interference (EMI), aging components (their expected lifetimes may stretch into decades), and poor transmission media.
Security
Because smart grid applications generally assume access by third parties to the same physical networks and underlying IP infrastructure of the grid, much work has been done to add Secure Authentication features to the DNP3 protocol. The DNP3 protocol is compliant with IEC 62351-5. Some vendors support encryption via bump-in-the-wire for seri
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https://en.wikipedia.org/wiki/Lightface%20analytic%20game
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In descriptive set theory, a lightface analytic game is a game whose payoff set A is a subset of Baire space; that is, there is a tree T on which is a computable subset of , such that A is the projection of the set of all branches of T.
The determinacy of all lightface analytic games is equivalent to the existence of 0#.
Effective descriptive set theory
Determinacy
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https://en.wikipedia.org/wiki/Deadlock%20%28game%20theory%29
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In game theory, Deadlock is a game where the action that is mutually most beneficial is also dominant. This provides a contrast to the Prisoner's Dilemma where the mutually most beneficial action is dominated. This makes Deadlock of rather less interest, since there is no conflict between self-interest and mutual benefit.
On the other hand, deadlock game can also impact the economic behaviour and changes to equilibrium outcome in society.
General definition
Any game that satisfies the following two conditions constitutes a Deadlock game: (1) e>g>a>c and (2) d>h>b>f. These conditions require that d and D be dominant. (d, D) be of mutual benefit, and that one prefer one's opponent play c rather than d.
Like the Prisoner's Dilemma, this game has one unique Nash equilibrium: (d, D).
Example
In this deadlock game, if Player C and Player D cooperate, they will get a payoff of 1 for both of them. If they both defect, they will get a payoff of 2 for each. However, if Player C cooperates and Player D defects, then C gets a payoff of 0 and D gets a payoff of 3.
Deadlock and social cooperation
Even though deadlock game can satisfy group and individual benefit at mean time, but it can be influenced by dynamic one-side-offer bargaining deadlock model.
As a result, deadlock negotiation may happen for buyers. To deal with deadlock negotiation, three types of strategies are founded to break through deadlock and buyer's negotiation. Firstly, using power move to put a price on the status quo to create a win-win situation. Secondly, process move is used for overpowering the deadlock negotiation. Lastly, appreciative moves can help buyer to satisfy their own perspectives and lead to successful cooperation.
References
External links and offline sources
GameTheory.net
C. Hauert: "Effects of space in 2 x 2 games". International Journal of Bifurcation and Chaos in Applied Sciences and Engineering 12 (2002) 1531–1548.
Non-cooperative games
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https://en.wikipedia.org/wiki/Online%20counseling
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Online counseling is a form of professional mental health counseling that is generally performed through the internet. Computer aided technologies are used by the trained professional counselors and individuals seeking counseling services to communicate rather than conventional face-to-face interactions. Online counseling is also referred to as teletherapy, e-therapy, cyber therapy, or web counseling. Services are typically offered via email, real-time chat, and video conferencing. Some clients use online counseling in conjunction with traditional psychotherapy, or nutritional counseling. An increasing number of clients are using online counseling as a replacement for office visits.
While some forms of telepsychology and telepsychiatry have been available for over 35 years, the development of internet video chat systems and the continued increase of the market penetration for the broadband has resulted in the continuing growth of online therapy. Some clients are using videoconferencing, live chat and email services with a mental health professional in place of or in addition to face-to-face meetings.
History
One of the first demonstrations of the Internet was a simulated psychotherapy session between computers at Stanford and UCLA during the International Conference on Computer Communication in October 1972. Although this was a simulation and not actual counseling, the demonstration created an interest in the potential of online communication for counseling. As access to the internet, bulletin boards, and online services became more available in the 1980s, and online communication became more common, virtual self-help groups naturally developed. These self-help groups may be considered a precursor to online counseling. When the World Wide Web became public in the early 1990s and mental health professionals began to create websites offering mental health information, some began to receive requests for personal help and started to respond to these requests, leadin
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https://en.wikipedia.org/wiki/Screen%20tearing
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Screen tearing is a visual artifact in video display where a display device shows information from multiple frames in a single screen draw.
The artifact occurs when the video feed to the device is not synchronized with the display's refresh rate. That can be caused by non-matching refresh rates, and the tear line then moves as the phase difference changes (with speed proportional to the difference of frame rates). It can also occur simply from a lack of synchronization between two equal frame rates, and the tear line is then at a fixed location that corresponds to the phase difference. During video motion, screen tearing creates a torn look as the edges of objects (such as a wall or a tree) fail to line up.
Tearing can occur with most common display technologies and video cards and is most noticeable in horizontally-moving visuals, such as in slow camera pans in a movie or classic side-scrolling video games.
Screen tearing is less noticeable when more than two frames finish rendering during the same refresh interval since that means the screen has several narrower tears, instead of a single wider one.
Prevention
Ways to prevent video tearing depend on the display device and video card technology, the software in use, and the nature of the video material. The most common solution is to use multiple buffering.
Most systems use multiple buffering and some means of synchronization of display and video memory refresh cycles.
Vertical synchronization
A vertical synchronization is an option in most systems in which the video card is prevented from doing anything visible to the display memory until after the monitor finishes its current refresh cycle.
During the vertical blanking interval, the driver orders the video card to either rapidly copy the off-screen graphics area into the active display area (double buffering), or treat both memory areas as displayable, and simply switch back and forth between them (page flipping).
Nvidia and AMD video adapters provide a
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https://en.wikipedia.org/wiki/Norman%20Macleod%20Ferrers
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Norman Macleod Ferrers (11 August 1829 – 31 January 1903) was a British mathematician and university administrator and editor of a mathematical journal.
Career and research
Ferrers was educated at Eton College before studying at Gonville and Caius College, Cambridge, where he was Senior Wrangler in 1851. He was appointed to a Fellowship at the college in 1852, was called to the bar in 1855 and was ordained deacon in 1859 and priest in 1860. In 1880, he was appointed Master of the college, and served as vice-chancellor of Cambridge University from 1884 to 1885.
Ferrers made many contributions to mathematical literature. From 1855 to 1891 he worked with J. J. Sylvester as editors, with others, in publishing The Quarterly Journal of Pure and Applied Mathematics. Ferrers assembled the papers of George Green for publication in 1871.
In 1861 he published "An Elementary Treatise on Trilinear Co-ordinates". One of his early contributions was on Sylvester's development of Poinsot's representation of the motion of a rigid body about a fixed point.
In 1871 he first suggested to extend the equations of motion with nonholonomic constraints.
His another treatise on "Spherical Harmonics," published in 1877, presented many original features.
In 1881 he studied Kelvin's investigation of the law of distribution of electricity in equilibrium on an uninfluenced spherical bowl
and made the addition of finding the potential at any point of space in zonal harmonics.
He died at the College Lodge on 31 January 1903.
Integer partitions
Ferrers is associated with a particular way of arranging the partition of a natural number p. If p is the sum of n terms, the largest of which is m, then the Ferrers diagram starts with a row of m dots. The terms are arranged in order, and a row of dots corresponds to each term.
Adams, Ferrers, and Sylvester articulated this theorem of partitions: "The number of modes of partitioning (n) into (m) parts is equal to the number of modes of partitioning
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https://en.wikipedia.org/wiki/Honeywell%20200
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The Honeywell 200 was a character-oriented two-address commercial computer introduced by Honeywell in December 1963, the basis of later models in Honeywell 200 Series, including 1200, 1250, 2200, 3200, 4200 and others, and the character processor of the Honeywell 8200 (1968).
Introduced to compete with IBM's 1401, the H200 was two or three times faster and, with software support, most of the time could execute IBM 1401 programs without need for their recompilation or reassembly. The Liberator marketing campaign exploited this compatibility, and was credited in later Honeywell publicity statements with stalling the sales of IBM 1401 machines. Honeywell claimed an initial rush of hundreds of orders for the H200 that itself stalled when IBM countered with a marketing emphasis on their System 360 product range that was then under development.
Architecture
As designed by Director of Engineering William L. Gordon, the H200 memory consisted of individually addressed characters, each composed of six data bits, two punctuation bits and a parity bit. The two punctuation bits recorded a word mark and an item mark, while both being set constituted a record mark. The item bit permitted item moves and record moves in addition to word moves (move successive characters one-by-one starting at the addresses given in the instruction, stopping when the relevant punctuation mark was found set in either field).
An instruction consisted of a one-character op-code, up to two operand addresses and an optional single character variant. Usually the op-code character would be word-marked, confirming the end of the previous instruction. An item-marked op-code would be handled differently from normal, and this was used in the emulation of IBM 1401 instructions that were not directly compatible. In two-character address mode, the full address defined one character in the 4K block currently addressed by the relevant register. In three-character address mode, the first three bits of an operan
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https://en.wikipedia.org/wiki/Index%20of%20aerospace%20engineering%20articles
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This is an alphabetical list of articles pertaining specifically to aerospace engineering. For a broad overview of engineering, see List of engineering topics. For biographies, see List of engineers.
A
Ablative laser propulsion —
Absolute value —
Acceleration —
Action —
Advanced Space Vision System —
Aeroacoustics —
Aerobrake —
Aerobraking —
Aerocapture —
Aerodynamics —
Aeroelasticity —
Aeronautical abbreviations —
Aeronautics —
Aerospace engineering —
Aerospike engine —
Aerostat —
Aft-crossing trajectory —
Aileron —
Air-augmented rocket —
Aircraft —
Aircraft flight control systems —
Aircraft flight mechanics —
Airfoil —
Airlock —
Airship —
Alcubierre drive —
Angle of attack —
Angular momentum —
Angular velocity —
Antimatter rocket —
Apsis —
Arcjet rocket —
Areal velocity —
ARP4761 —
Aspect ratio (wing) —
Astrodynamics —
Atmospheric reentry —
Attitude control —
Avionics —
B
Balloon —
Ballute —
Beam-powered propulsion —
Bernoulli's equation —
Bi-elliptic transfer —
Big dumb booster —
Bipropellant rocket —
Bleed air —
Booster rocket —
Breakthrough Propulsion Physics Program —
Buoyancy —
Bussard ramjet —
C
Canard —
Centennial challenges —
Center of gravity —
Center of mass —
Center of pressure —
Chord —
Collimated light —
Compressibility —
Computational fluid dynamics —
Computing —
Control engineering —
Conservation of momentum —
Crew Exploration Vehicle —
Critical mach —
Centrifugal compressor —
Chevron nozzle —
D
De Laval nozzle —
Deflection —
Delta-v —
Delta-v budget —
Density —
Derivative —
Digital Datcom —
Displacement (vector) —
DO-178B —
DO-254 —
Drag (physics) —
Drag coefficient —
Drag equation —
Dual mode propulsion rocket —
Delta wing —
E
Earth's atmosphere —
Electrostatic ion thruster —
Elliptic partial differential equation —
Energy —
Engineering —
Engineering economics —
Enstrophy —
Equation of motion —
Euler angles —
European Space Agency —
Expander cycle (rocket) —
F
Field Emission Electric Propulsion —
Fixed-wing aircraft —
Flight control surfaces
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https://en.wikipedia.org/wiki/Design%20for%20testing
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Design for testing or design for testability (DFT) consists of IC design techniques that add testability features to a hardware product design. The added features make it easier to develop and apply manufacturing tests to the designed hardware. The purpose of manufacturing tests is to validate that the product hardware contains no manufacturing defects that could adversely affect the product's correct functioning.
Tests are applied at several steps in the hardware manufacturing flow and, for certain products, may also be used for hardware maintenance in the customer's environment. The tests are generally driven by test programs that execute using automatic test equipment (ATE) or, in the case of system maintenance, inside the assembled system itself. In addition to finding and indicating the presence of defects (i.e., the test fails), tests may be able to log diagnostic information about the nature of the encountered test fails. The diagnostic information can be used to locate the source of the failure.
In other words, the response of vectors (patterns) from a good circuit is compared with the response of vectors (using the same patterns) from a DUT (device under test). If the response is the same or matches, the circuit is good. Otherwise, the circuit is not manufactured as it was intended.
DFT plays an important role in the development of test programs and as an interface for test application and diagnostics. Automatic test pattern generation, or ATPG, is much easier if appropriate DFT rules and suggestions have been implemented.
History
DFT techniques have been used at least since the early days of electric/electronic data processing equipment. Early examples from the 1940s/50s are the switches and instruments that allowed an engineer to "scan" (i.e., selectively probe) the voltage/current at some internal nodes in an analog computer [analog scan]. DFT often is associated with design modifications that provide improved access to internal circuit elemen
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https://en.wikipedia.org/wiki/Electrical%20ballast
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An electrical ballast is a device placed in series with a load to limit the amount of current in an electrical circuit.
A familiar and widely used example is the inductive ballast used in fluorescent lamps to limit the current through the tube, which would otherwise rise to a destructive level due to the negative differential resistance of the tube's voltage-current characteristic.
Ballasts vary greatly in complexity. They may be as simple as a resistor, inductor, or capacitor (or a combination of these) wired in series with the lamp; or as complex as the electronic ballasts used in compact fluorescent lamps (CFLs).
Current limiting
An electrical ballast is a device that limits the current through an electrical load. These are most often used when a load (such as an arc discharge) has its terminal voltage decline when current through the load increases. If such a device were connected to a constant-voltage power supply, it would draw an increasing amount of current until it is destroyed or causes the power supply to fail. To prevent this, a ballast provides a positive resistance or reactance that limits the current. The ballast provides for the proper operation of the negative-resistance device by limiting current.
Ballasts can also be used simply to limit the current in an ordinary, positive-resistance circuit. Prior to the advent of solid-state ignition, automobile ignition systems commonly included a ballast resistor to regulate the voltage applied to the ignition system.
Resistors
Fixed resistors
For simple, low-powered loads such as a neon lamp, a fixed resistor is commonly used. Because the resistance of the ballast resistor is large it determines the current in the circuit, even in the face of negative resistance introduced by the neon lamp.
Ballast was also a component used in early model automobile engines that lowered the supply voltage to the ignition system after the engine had been started. Starting the engine requires a significant amount
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https://en.wikipedia.org/wiki/International%20Food%20Policy%20Research%20Institute
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The International Food Policy Research Institute (IFPRI) is an international agricultural research center founded in 1975 to improve the understanding of national agricultural and food policies to promote the adoption of innovations in agricultural technology. Additionally, IFPRI was meant to shed more light on the role of agricultural and rural development in the broader development pathway of a country. The mission of IFPRI is to provide research-based policy solutions that sustainably reduce poverty and end hunger and malnutrition.
IFPRI carries out food policy research and disseminates it through hundreds of publications, bulletins, conferences, and other initiatives. IFPRI was organized as a District of Columbia non-profit, non-stock corporation on March 5, 1975, and its first research bulletin was produced in February 1976. IFPRI operates in more than 50 countries with offices in several developing countries, including China, Ethiopia, and India, and has research staff working in many more countries around the world. Most of the research takes place in developing countries in Central America, South America, Africa, and Asia.
IFPRI is part of a network of international research institutes funded in part by the CGIAR, which in turn is funded by governments, private businesses and foundations, and the World Bank.
Scope
IFPRI's institutional strategy rests on three pillars: research, capacity strengthening, and policy communication.
Research areas
Research topics have included low crop and animal productivity, and environmental degradation, water management, fragile lands, property rights, collective action, sustainable intensification of agricultural production, the impact of climate change on poor farmers, the problems and opportunities of biotechnology, food security, micronutrient malnutrition, microfinance programs, urban food security, resource allocation within households, and school feeding in low-income countries.
Gender and development
One major ar
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https://en.wikipedia.org/wiki/Enzyme%20assay
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Enzyme assays are laboratory methods for measuring enzymatic activity. They are vital for the study of enzyme kinetics and enzyme inhibition.
Enzyme units
The quantity or concentration of an enzyme can be expressed in molar amounts, as with any other chemical, or in terms of activity in enzyme units.
Enzyme activity
Enzyme activity is a measure of the quantity of active enzyme present and is thus dependent on various physical conditions, which should be specified.
It is calculated using the following formula:
where
Enzyme activity
Moles of substrate converted per unit time
Rate of the reaction
Reaction volume
The SI unit is the katal, 1 katal = 1 mol s−1 (mole per second), but this is an excessively large unit. A more practical and commonly used value is enzyme unit (U) = 1 μmol min−1 (micromole per minute). 1 U corresponds to 16.67 nanokatals.
Enzyme activity as given in katal generally refers to that of the assumed natural target substrate of the enzyme. Enzyme activity can also be given as that of certain standardized substrates, such as gelatin, then measured in gelatin digesting units (GDU), or milk proteins, then measured in milk clotting units (MCU). The units GDU and MCU are based on how fast one gram of the enzyme will digest gelatin or milk proteins, respectively. 1 GDU approximately equals 1.5 MCU.
An increased amount of substrate will increase the rate of reaction with enzymes, however once past a certain point, the rate of reaction will level out because the amount of active sites available has stayed constant.
Specific activity
The specific activity of an enzyme is another common unit. This is the activity of an enzyme per milligram of total protein (expressed in μmol min−1 mg−1). Specific activity gives a measurement of enzyme purity in the mixture. It is the micro moles of product formed by an enzyme in a given amount of time (minutes) under given conditions per milligram of total proteins. Specific activity is equal to the rate of reacti
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https://en.wikipedia.org/wiki/Demister%20%28vapor%29
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A demister is a device often fitted to vapor–liquid separator vessels to enhance the removal of liquid droplets entrained in a vapor stream. Demisters may be a mesh-type coalescer, vane pack or other structure intended to aggregate the mist into droplets that are heavy enough to separate from the vapor stream.
Demisters can reduce the residence time required to separate a given liquid droplet size by reducing the volume and associated cost of separator equipment. Demisters are often used where vapor quality is important in regard to entrained liquids, particularly where separator equipment costs are high (e.g., high-pressure systems) or where space or weight savings are advantageous.
For example, in the process of brine desalination on marine vessels, brine is flash-heated into vapor. In flashing, vapor carries over droplets of brine, which have to be separated before condensing, otherwise the distillate vapor would be contaminated with salt. This is the role of the demister. Demisted vapor condenses on tubes in the desalination plant, and product water is collected in the distillate tray.
See also
Vapor–liquid separator
Souders–Brown equation
Vane type separator
Vessel Internals
Gas Processors Suppliers Association (GPSA)
References
Chemical equipment
Gas technologies
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https://en.wikipedia.org/wiki/Index%20of%20mechanical%20engineering%20articles
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This is an alphabetical list of articles pertaining specifically to mechanical engineering. For a broad overview of engineering, please see List of engineering topics. For biographies please see List of engineers.
A
Acceleration –
Accuracy and precision –
Actual mechanical advantage –
Aerodynamics –
Agitator (device) –
Air handler –
Air conditioner –
Air preheater –
Allowance –
American Machinists' Handbook –
American Society of Mechanical Engineers –
Ampere –
Applied mechanics –
Antifriction –
Archimedes' screw –
Artificial intelligence –
Automaton clock –
Automobile –
Automotive engineering –
Axle –
Air Compressor
B
Backlash –
Balancing –
Beale Number –
Bearing –
Belt (mechanical) –
Bending –
Biomechatronics –
Bogie –
Brittle –
Buckling –
Bus--
Bushing –
Boilers & boiler systems
BIW--
C
CAD –
CAM –
CAID –
Calculator –
Calculus –
Car handling –
Carbon fiber –
Classical mechanics –
Clean room design –
Clock –
Clutch –
CNC –
Coefficient of thermal expansion –
Coil spring –
Combustion –
Composite material –
Compression ratio –
Compressive strength –
Computational fluid dynamics –
Computer –
Computer-aided design –
Computer-aided industrial design –
Computer-numerically controlled –
Conservation of mass –
Constant-velocity joint –
Constraint –
Continuum mechanics –
Control theory –
Corrosion –
Cotter pin –
Crankshaft –
Cybernetics –
D
Damping ratio –
Deformation (engineering) –
Delamination –
Design –
Diesel Engine –
Differential –
Dimensionless number –
Diode –
Diode laser –
Drafting –
Drifting –
Driveshaft –
Dynamics –
Design for Manufacturability for CNC machining –
E
Elasticity –
Elasticity tensor -
Electric motor –
Electrical engineering –
Electrical circuit –
Electrical network –
Electromagnetism –
Electronic circuit –
Electronics –
Energy –
Engine –
Engineering –
Engineering cybernetics –
Engineering drawing –
Engineering economics –
Engineering ethics –
Engineering management –
Engineering society –
Exploratory engineering –
F
( Fits and tolerances)---
Fa
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https://en.wikipedia.org/wiki/Higher-order%20abstract%20syntax
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In computer science, higher-order abstract syntax (abbreviated HOAS) is a technique for the representation of abstract syntax trees for languages with variable binders.
Relation to first-order abstract syntax
An abstract syntax is abstract because it is represented by mathematical objects that have certain structure by their very nature. For instance, in first-order abstract syntax (FOAS) trees, as commonly used in compilers, the tree structure implies the subexpression relation, meaning that no parentheses are required to disambiguate programs (as they are, in the concrete syntax). HOAS exposes additional structure: the relationship between variables and their binding sites. In FOAS representations, a variable is typically represented with an identifier, with the relation between binding site and use being indicated by using the same identifier. With HOAS, there is no name for the variable; each use of the variable refers directly to the binding site.
There are a number of reasons why this technique is useful. First, it makes the binding structure of a program explicit: just as there is no need to explain operator precedence in a FOAS representation, there is no need to have the rules of binding and scope at hand to interpret a HOAS representation. Second, programs that are
alpha-equivalent (differing only in the names of bound variables) have identical representations in HOAS, which can make equivalence checking more efficient.
Implementation
One mathematical object that could be used to implement HOAS is a graph where variables are associated with their binding sites via edges. Another popular way to implement HOAS (in, for example, compilers) is with de Bruijn indices.
Use in logic programming
The first programming language which directly supported
λ-bindings in syntax was the higher-order logic programming
language λProlog.
The paper that introduced the term HOAS
used
λProlog code to illustrate it. Unfortunately, when one transfers the
term HOAS from t
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https://en.wikipedia.org/wiki/K%C4%ABpuka
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A kīpuka is an area of land surrounded by one or more younger lava flows. A kīpuka forms when lava flows on either side of a hill, ridge, or older lava dome as it moves downslope or spreads from its source. Older and more weathered than their surroundings, kīpukas often appear to be like islands within a sea of lava flows. They are often covered with soil and late ecological successional vegetation that provide visual contrast as well as habitat for animals in an otherwise inhospitable environment. In volcanic landscapes, kīpukas play an important role as biological reservoirs or refugia for plants and animals, from which the covered land can be recolonized.
Etymology
Kīpuka, along with aā and pāhoehoe, are Hawaiian words related to volcanology that have entered the lexicon of geology. Descriptive proverbs and poetical sayings in Hawaiian oral tradition also use the word, in an allusive sense, to mean a place where life or culture endures, regardless of any encroachment or interference. By extension, from the appearance of island "patches" within a highly contrasted background, any similarly noticeable variation or change of form, such as an opening in a forest, or a clear place in a congested setting, may be colloquially called kīpuka.
Significance to research
Kīpuka provides useful study sites for ecological research because they facilitate replication; multiple kīpuka in a system (isolated by the same lava flow) will tend to have uniform substrate age and successional characteristics, but are often isolated-enough from their neighbors to provide meaningful, comparable differences in size, invasion, etc. They are also receptive to experimental treatments. Kīpuka along Saddle Road on Hawaii have served as the natural laboratory for a variety of studies, examining ecological principles like island biogeography, food web control, and biotic resistance to invasiveness. In addition, Drosophila silvestris populations inhabit kīpukas, making kīpukas useful for unders
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https://en.wikipedia.org/wiki/Macrometer
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A macrometer is an instrument for measuring the size and distance of distant objects. Distant in this sense means a length that can not be readily measured by a calibrated length. The optical version of this instrument used two mirrors on a common sextant. By aligning the object on the mirrors using a precise vernier, the position of the mirrors could be used to compute the range to the object. The distance and the angular size of the object would then yield the actual size.
See also
Rangefinder
Theodolite
References
Surveying instruments
Surveying
Length, distance, or range measuring devices
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https://en.wikipedia.org/wiki/Password%20psychology
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Living in the intersection of cryptography and psychology, password psychology is the study of what makes passwords or cryptographic keys easy to remember or guess.
In order for a password to work successfully and provide security to its user, it must be kept secret and un-guessable; this also requires the user to memorize their password. The psychology behind choosing a password is a unique balance between memorization, security and convenience. Password security involves many psychological and social issues including; whether or not to share a password, the feeling of security, and the eventual choice of whether or not to change a password. Passwords may also be reflective of personality. Those who are more uptight or security-oriented may choose longer or more complicated passwords. Those who are lax or who feel more secure in their everyday lives may never change their password. The most common password is Password1, which may point to convenience over security as the main concern for internet users.
History
The use and memorization of both nonsense and meaningful alphanumeric material has had a long history in psychology beginning with Hermann Ebbinghaus. Since then, numerous studies have established that not only are both meaningful and nonsense “words” easily forgotten, but that both their forgetting curves are exponential with time. Chomsky advocates meaning as arising from semantic features, leading to the idea of “concept formation” in the 1930s.
Current research
Research is being done to find new ways of enhancing and creating new techniques for cognitive ability and memorization when it comes to password selection. A study from 2004 indicates that the typical college student creates about 4 different passwords for use with about 8 different items, such as computers, cell phones, and email accounts, and the typical password is used for about two items. Information about the type of passwords points to an approximate even split between linguistic and nu
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https://en.wikipedia.org/wiki/Brute%20Force%3A%20Cracking%20the%20Data%20Encryption%20Standard
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Brute Force: Cracking the Data Encryption Standard (2005, Copernicus Books ) is a book by Matt Curtin about cryptography.
In this book, the author accounts his involvement in the DESCHALL Project, mobilizing thousands of personal computers in 1997 in order to meet the challenge to crack a single message encrypted with DES.
This was and remains one of the largest collaborations of any kind on a single project in history.
The message was unencrypted on June 18 and was found to be "Strong cryptography makes the world a safer place."
This is also the message of Curtin's book where he uses a personal account to reveal to the uninitiated reader some insight into a topic of growing importance which is both technically and politically complicated.
External links
Archive of project material
Archive of DESCHALL home page
2005 non-fiction books
Cryptography books
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https://en.wikipedia.org/wiki/MetaWeblog
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The MetaWeblog API is an application programming interface created by software developer Dave Winer that enables weblog entries to be written, edited, and deleted using web services.
The API is implemented as an XML-RPC web service with three methods whose names describe their function: metaweblog.newPost(), metaweblog.getPost() and metaweblog.editPost(). These methods take arguments that specify the blog author's username and password along with information related to an individual weblog entry.
The impetus for the creation of the API in 2002 was perceived limitations of the Blogger API, which serves the same purpose. Another weblog publishing API, the Atom Publishing Protocol became an IETF Internet standard (RFC 5023) in October 2007. Subsequently, another weblog publishing API, Micropub, which was developed with modern technologies like OAuth, became a W3C Recommendation in May 2017.
Many blog software applications and content management systems support the MetaWeblog API, as do numerous desktop clients.
See also
Atom Publishing Protocol
Micropub
XML-based standards
Web services
Inter-process communication
Internet protocols
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https://en.wikipedia.org/wiki/People%20Finder%20Interchange%20Format
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People Finder Interchange Format (PFIF) is a widely used open data standard for information about missing or displaced people. PFIF was designed to enable information sharing among governments, relief organizations, and other survivor registries to help people find and contact their family and friends after a disaster.
Overview
PFIF is extended from XML. It consists of person records, which contain identifying information about a person, and note records, which contain comments and updates on the status and location of a person. Each note is attached to one person. PFIF defines the set of fields in these records and an XML-based format to store or transfer them. PFIF XML records can be embedded in Atom feeds or RSS feeds.
PFIF allows different repositories of missing person data to exchange and aggregate their records. Every record has a unique identifier, which indicates the domain name of the original repository where the record was created. The unique record identifier is preserved as the record is copied from one repository to another. For example, any repository that receives a copy of a given person can publish a note attached to that person, and even as the note and person are copied to other repositories, they remain traceable to their respective original sources.
History
Within three days after the 2001 September 11 attacks, people were using over 25 different online forums and survivor registries to report and check on their family and friends.
One of the first and largest of these was the survivor registry at safe.millennium.berkeley.edu, which was created by graduate students Ka-Ping Yee and Miriam Walker and hosted on the Millennium computer cluster at UC Berkeley. To reduce the confusion caused by the proliferation of different websites, the Berkeley survivor registry began collecting data from several of the other major sites into one searchable database. Because the information was formatted differently from site to site, each site required manu
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https://en.wikipedia.org/wiki/Tokyo%20Skytree
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, is a broadcasting and observation tower in Sumida, Tokyo. It became the tallest structure in Japan in 2010 and reached its full height of in March 2011, making it the tallest tower in the world, displacing the Canton Tower, and the third tallest structure in the world after the Merdeka 118 () and the Burj Khalifa (829.8 m or 2,722 ft). It is also the tallest freestanding structure in the OECD, the G20 and G7 countries.
The tower is the primary television and radio broadcast site for the Kantō region; the older Tokyo Tower no longer gives complete digital terrestrial television broadcasting coverage because it is surrounded by high-rise buildings. Skytree was completed on Leap Day, 29 February 2012, with the tower opening to the public on 22 May 2012. The tower is the centrepiece of a large commercial development funded by Tobu Railway (which owns the complex) and a group of six terrestrial broadcasters headed by NHK. Trains stop at the adjacent Tokyo Skytree Station and nearby Oshiage Station. The complex is northeast of Tokyo Station. In addition, there is the Sumida Aquarium in the "Tokyo Solamachi" complex.
Design
The tower's design was published on 24 November 2006, based on the following three concepts:
Fusion of neofuturistic design and the traditional beauty of Japan
Catalyst for revitalization of the city
Contribution to disaster prevention – "Safety and Security"
The base of the tower has a structure similar to a tripod; from a height of about and above, the tower's structure is cylindrical to offer panoramic views of the river and the city. There are observatories at , with a capacity of up to 2,000 people, and , with a capacity of 900 people. The upper observatory features a spiral, glass-covered skywalk in which visitors ascend the last 5 metres to the highest point at the upper platform. A section of glass flooring gives visitors a direct downward view of the streets below.
Earthquake resistance
The tower has seismic proofing, including a ce
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https://en.wikipedia.org/wiki/KHRR
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KHRR (channel 40) is a television station in Tucson, Arizona, United States, serving as the market's outlet for the Spanish-language network Telemundo. Owned and operated by NBCUniversal's Telemundo Station Group, the station maintains studios on North Stone Avenue in downtown Tucson, and its transmitter is located atop the Tucson Mountains.
Although identifying as a separate station in its own right, KHRR is considered a semi-satellite of KTAZ (channel 39) in Phoenix. As such, it simulcasts all Telemundo programming as provided through its parent, but airs separate commercial inserts and legal identifications, and has its own website. Local newscasts, produced by KTAZ and branded as Noticiero Telemundo Arizona, are simulcast on both stations. Although KHRR maintains its own facilities, master control and most internal operations are based at KTAZ's studios on South 33rd Place in Phoenix.
History
KPOL
On November 28, 1983, a construction permit was granted to JP Communications, owned by Julius Polan of Chicago, for a new commercial television station on channel 40 in Tucson. Channel 40 had been occupied since November 1980 by a translator of Phoenix Spanish-language station KTVW. JP beat out Valle Verde Broadcasting Corporation, which proposed a full-service Spanish-language outlet, and five other applicants, including Focus Broadcasting and National Group Telecommunications. The permit was approved after JP paid out a cash settlement to rival Sunwest Communications.
Taking the call letters KPOL, construction began in 1984, forcing the KTVW translator to move to channel 52. The station also secured a package of Phoenix Suns road games. However, channel 40 missed its planned November start because its studios had not been completed. Meanwhile, minority investor David Jácome sued, saying that Polan had brought him in to add a minority owner to the ownership group but that he had been squeezed out.
KPOL signed on January 5, 1985. It was the second new independent
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https://en.wikipedia.org/wiki/Organizational-dynamic%20game
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Organizational-dynamic games are Serious games that teach and reflect the dynamics of organizations at the following 3 levels:
individual behavior (specific attitudes towards collaboration or knowledge sharing, competencies, character traits, motivation, change readiness, etc.)
group and network dynamics (power and influence pattern, sub-group behavior, team dynamics as in Group-dynamic games, etc.)
cultural dynamics (specific values, dominant mental and behavioral models, etc.)
Organizational-dynamic games are usually designed for the specific purpose of furthering personal development and character building, particularly in addressing complex organizational situations, such as managing change and innovation diffusion in a company, helping people in the organization to introduce productive collaboration patterns, managing difficult meeting situations, etc.
They have a proven history in helping managers and decision makers in better understanding organizational dynamics, the diagnosis of organizational contexts, and the impact of organizational interventions (corresponding to the actions you can undertake in such a simulation to achieve a result (e.g. a change in attitude or behavior).
See the example of the EIS simulation .
Examples
Awkward Moment at Work: serious game with a design informed by psychological theory and research, aimed at reducing gender bias and broadening participation in STEM.
Houthoff Buruma The Game: serious game for recruitment purposes, developed by Dutch law firm Houthoff Buruma.
Novicraft HRD game (Microsoft Windows): NoviCraft is a serious game for supporting business customers in social excellence, in learning to construct shared understanding together with different people in changing contexts.
CALM: Change Adaptation Learning Model: serious game for testing, validating, and refining plans to enable transformational organizational change. Developed by DecisionPath, Inc. see: [R.M. Adler and D. Koehn, “CALM: complex adaptiv
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https://en.wikipedia.org/wiki/Blue%20ice%20%28aviation%29
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In aviation, blue ice is frozen sewage material that has leaked mid-flight from commercial aircraft lavatory waste systems. It is a mixture of human biowaste and liquid disinfectant that freezes at high altitude. The name comes from the blue color of the disinfectant. Airlines are not allowed to dump their waste tanks mid-flight, and pilots have no mechanism by which to do so; however, leaks sometimes do occur from a plane's septic tank.
Danger of ground impact
There were at least 27 documented incidents of blue ice impacts in the United States between 1979 and 2003. These incidents typically happen under airport landing paths as the mass warms sufficiently to detach from the plane during its descent. A rare incident of falling blue ice causing damage to the roof of a home was reported on October 20, 2006 in Chino, California. A similar incident was reported in Leicester, UK, in 2007.
In 1971, a chunk of ice from an aircraft tore a large hole in the roof of the Essex Street Chapel in Kensington, London, and was one trigger for the demolition of the building.
In November 2011, a chunk of ice, the size of an orange, broke through the roof of a private house in Ratingen-Hösel, Germany.
In February 2013, a "football sized" ball of blue ice smashed through a conservatory roof in Clanfield, Hampshire, causing around £10,000 worth of damage.
In October 2016, a chunk of ice tore a hole in a private house in Amstelveen, The Netherlands.
In two incidents in May 2018, chunks of blue ice fell onto residents in Kelowna, British Columbia.
In November 2018, a chunk of ice fell from the sky and crashed through the roof of a home in Bristol, England.
Danger to aircraft
Blue ice can also be dangerous to the aircraft the National Transportation Safety Board has recorded three very similar incidents where waste from lavatories caused damage to the leaking aircraft, all involving Boeing 727s. In all three cases, waste from a leaking lavatory hit one (or the other) of the three
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https://en.wikipedia.org/wiki/Shelter%20from%20the%20Storm%3A%20A%20Concert%20for%20the%20Gulf%20Coast
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Shelter from the Storm: A Concert for the Gulf Coast was a one-hour, commercial-free benefit concert television special that aired simulcast worldwide on September 9, 2005, at 8 p.m. ET/CT live (with a 30-second tape delay) from New York City and Los Angeles and tape delayed in the Mountain Time Zone and Pacific Time Zones. The special raised money for the relief efforts from the aftermath of Hurricane Katrina. It was broadcast in over 100 different countries. All proceeds went to the American Red Cross and The Salvation Army.
Production
The concert was a cooperative and collaborative global effort between ABC, CBS, NBC, FOX, UPN, and The WB. Several cable stations have also cleared space for the concert. It featured appearances and musical performances by celebrities from the world of film, television and music. Approximately $30 million was raised for the American Red Cross and The Salvation Army.
The event was produced by Joel Gallen and followed closely in the footprints of the 9/11 benefit concert, America: A Tribute to Heroes, which Gallen also produced. It featured performances by popular musicians along with commentary by various actors and other celebrities. Celebrities also answered phone calls to help collect donations.
Musical guests and performances
Randy Newman, "Louisiana 1927"
U2 with Mary J. Blige, "One" (recorded earlier that day in Toronto)
Alicia Keys with Alvin Slaughter, Shirley Caesar and Bishop Eric McDaniel: Gospel Medley: "Remember Me", Come by Here, My Lord" and "We Need To Hear From You"
Neil Young, "When God Made Me"
Foo Fighters, "Born on the Bayou"
Mariah Carey, "Fly Like a Bird"
Paul Simon, "Take Me to the Mardi Gras"
unknown New Orleans jazz band, coda
Dixie Chicks with Mike Campbell and Robert Randolph, "I Hope"
Kelly Clarkson, "Shelter"
Sheryl Crow, "The Water Is Wide"
Rod Stewart with Jerry Lawson & Talk of the Town, "People Get Ready"
Kanye West, "Jesus Walks"
Garth Brooks with Trisha Yearwood and Paul Shaffer, "Who'll Stop
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https://en.wikipedia.org/wiki/Circular%20dependency
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In software engineering, a circular dependency is a relation between two or more modules which either directly or indirectly depend on each other to function properly. Such modules are also known as mutually recursive.
Overview
Circular dependencies are natural in many domain models where certain objects of the same domain depend on each other. However, in software design, circular dependencies between larger software modules are considered an anti-pattern because of their negative effects. Despite this, such circular (or cyclic) dependencies have been found to be widespread among the source files of real-world software. Mutually recursive modules are, however, somewhat common in functional programming, where inductive and recursive definitions are often encouraged.
Problems
Circular dependencies can cause many unwanted effects in software programs. Most problematic from a software design point of view is the tight coupling of the mutually dependent modules which reduces or makes impossible the separate re-use of a single module.
Circular dependencies can cause a domino effect when a small local change in one module spreads into other modules and has unwanted global effects (program errors, compile errors). Circular dependencies can also result in infinite recursions or other unexpected failures.
Circular dependencies may also cause memory leaks by preventing certain automatic garbage collectors (those that use reference counting) from deallocating unused objects.
Causes and solutions
In very large software designs, software engineers may lose the context and inadvertently introduce circular dependencies. There are tools to analyze software and find unwanted circular dependencies.
Circular dependencies can be introduced when implementing callback functionality. This can be avoided by applying design patterns like the observer pattern.
See also
Acyclic dependencies principle
Dependency hell
References
Programming language topics
C++
Articles with example
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https://en.wikipedia.org/wiki/Program%20Design%20Language
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Program Design Language (or PDL, for short) is a method for designing and documenting methods and procedures in software. It is related to pseudocode, but unlike pseudocode, it is written in plain language without any terms that could suggest the use of any programming language or library.
PDL was originally developed by the company Caine, Farber & Gordon and has been modified substantially since they published their initial paper on it in 1975. It has been described in some detail by Steve McConnell in his book Code Complete.
See also
Pseudocode
FLOW CHART
External links
Using PDL for Code Design and Documentation
PDL/81 Home Page by Caine, Farber & Gordon, Inc.
C STYLE GUIDE from Goddard Space Flight Center, National Aeronautics and Space Administration.
Algorithm description languages
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https://en.wikipedia.org/wiki/Namesco
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Namesco Ltd (names.co.uk) provides professional online services for individuals and businesses including domain name registration, web hosting, website building tools, email services, ecommerce solutions and a range of managed and unmanaged servers.
History
Namesco was founded by Richard and Rachel Suthering as a small Internet startup named "Names.co Internet Services Limited" originally based in North East England. In 1997 another Internet startup was founded by Kevin Savage, Jason Smith and John Sewell named Phase8.com "Webcall.com Limited" based in Worcester.
Following the dot com boom, Names.co Internet Services Limited became a Public Limited Company and floated on the London Unlisted Securities Market with a new name of Namesco Internet Plc in 2000. The following year, they acquired Phase8.com "Webcall.com Limited" for the sum of £2,450,000.
Despite acquiring smaller web hosting companies and resellers along the way, including SmartChoiceNet, the "publicly quoted" Namesco struggled to be viable citing the increasingly competitive nature of the domain name and web hosting business, and the additional costs of maintaining listed status as the reasons for a lack of profitability.
In 2002, it was rumoured that Ian Gowrie-Smith, Australian chairman of drug company SkyePharma was planning a reverse takeover of Namesco with the assistance of its chief executive and finance director, David Lees.
Trading of Namesco shares on AIM were suspended on 19 December 2003 prior to the announcement of Gowrie-Smith’s action. A Vietnamese gold mining company, Larchland, was injected into the company in a £19.6million reverse takeover deal that saw the business renamed as Triple Junction PLC. Namesco was hived down into a subsidiary and sold to Womerah Limited.
As a privately owned company, Namesco then had the capital to make new acquisitions as part of their growth strategy. In July 2004, they acquired NamesWeb; a small domain and web hosting business, and on 17 Septemb
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https://en.wikipedia.org/wiki/Autoload
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In computer programming, autoloading is the capability of loading and linking portions of a program from mass storage automatically when needed, so that the programmer is not required to define or include those portions of the program explicitly. Many high-level programming languages include autoload capabilities, which sacrifice some run-time speed for ease of coding and speed of initial compilation/linking.
Typical autoload systems intercept procedure calls to undefined subroutines. The autoloader searches through a path of directories in the computer's file system, to find a file containing source or object code that defines the subroutine. The autoloader then loads and links the file, and hands control back to the main program so that the subroutine gets executed as if it had already been defined and linked before the call.
Many interactive and high-level languages operate in this way. For example, IDL includes a primitive path searcher, and Perl allows individual modules to determine how and whether autoloading should occur. The Unix shell may be said to consist almost entirely of an autoloader, as its main job is to search a path of directories to load and execute command files. In PHP 5, autoload functionality is triggered when referencing an undefined class. One or more autoload functions—implemented as the __autoload magic function or any function registered to the SPL autoload stack—is called and given the opportunity to define the class, usually by loading the file it is defined in.
PHP
spl_autoload_register(function ($class) {
$file = 'src/' . str_replace('\\', '/', $relative_class) . '.php';
if (file_exists($file)) {
require $file;
}
});
External links
PSR-4 Improved Autoloading Standard
Autoloading Classes in PHP
spl_autoload_register in PHP
Programming constructs
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https://en.wikipedia.org/wiki/Magic%20%28programming%29
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In the context of computer programming, magic is an informal term for abstraction; it is used to describe code that handles complex tasks while hiding that complexity to present a simple interface. The term is somewhat tongue-in-cheek, and often carries bad connotations, implying that the true behavior of the code is not immediately apparent. For example, Perl's polymorphic typing and closure mechanisms are often called "magic". The term implies that the hidden complexity is at least in principle understandable, in contrast to black magic and deep magic (see Variants), which describe arcane techniques that are deliberately hidden or extremely difficult to understand. However, the term can also be applied endearingly, suggesting a "charm" about the code. The action of such abstractions is described as being done "automagically", a portmanteau of "automatically" and "magically".
Referential opacity
"Magic" refers to procedures which make calculations based on data not clearly provided to them, by accessing other modules, memory positions or global variables that they are not supposed to (in other words, they are not referentially transparent). According to most recent software architecture models, even when using structured programming, it is usually preferred to make each function behave the same way every time the same arguments are passed to it, thereby following one of the basic principles of functional programming. When a function breaks this rule, it is often said to contain "magic".
A simplified example of negative magic is the following code in PHP:
function magic()
{
global $somevariable;
echo $somevariable;
}
$somevariable = true;
magic();
While the code above is clear and maintainable, if it is seen in a large project, it is often hard to understand where the function magic() gets its value from. It is preferred to write that code using the following concept:
function noMagic($myvariable)
{
echo $myvariable;
}
$somevariable = true;
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https://en.wikipedia.org/wiki/Applied%20physics
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Applied physics is the application of physics to solve scientific or engineering problems. It is usually considered a bridge or a connection between physics and engineering.
"Applied" is distinguished from "pure" by a subtle combination of factors, such as the motivation and attitude of researchers and the nature of the relationship to the technology or science that may be affected by the work. Applied physics is rooted in the fundamental truths and basic concepts of the physical sciences but is concerned with the utilization of scientific principles in practical devices and systems and with the application of physics in other areas of science and high technology.
Examples of research and development areas
Accelerator physics
Acoustics
Atmospheric physics
Biophysics
Brain–computer interfacing
Chemistry
Chemical physics
Differentiable programming
Artificial intelligence
Scientific computing
Engineering physics
Chemical engineering
Electrical engineering
Electronics
Sensors
Transistors
Materials science and engineering
Metamaterials
Nanotechnology
Semiconductors
Thin films
Mechanical engineering
Aerospace engineering
Astrodynamics
Electromagnetic propulsion
Fluid mechanics
Military engineering
Lidar
Radar
Sonar
Stealth technology
Nuclear engineering
Fission reactors
Fusion reactors
Optical engineering
Photonics
Cavity optomechanics
Lasers
Photonic crystals
Geophysics
Materials physics
Medical physics
Health physics
Radiation dosimetry
Medical imaging
Magnetic resonance imaging
Radiation therapy
Microscopy
Scanning probe microscopy
Atomic force microscopy
Scanning tunneling microscopy
Scanning electron microscopy
Transmission electron microscopy
Nuclear physics
Fission
Fusion
Optical physics
Nonlinear optics
Quantum optics
Plasma physics
Quantum technology
Quantum computing
Quantum cryptography
Renewable energy
Space physics
Spectroscopy
See also
Applied science
Applied mathematics
Engineering
Engineering Physics
High Technology
References
Engineering disciplines
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https://en.wikipedia.org/wiki/Problem%20of%20Apollonius
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In Euclidean plane geometry, Apollonius's problem is to construct circles that are tangent to three given circles in a plane (Figure 1). Apollonius of Perga (c. 262 190 BC) posed and solved this famous problem in his work (, "Tangencies"); this work has been lost, but a 4th-century AD report of his results by Pappus of Alexandria has survived. Three given circles generically have eight different circles that are tangent to them (Figure 2), a pair of solutions for each way to divide the three given circles in two subsets (there are 4 ways to divide a set of cardinality 3 in 2 parts).
In the 16th century, Adriaan van Roomen solved the problem using intersecting hyperbolas, but this solution does not use only straightedge and compass constructions. François Viète found such a solution by exploiting limiting cases: any of the three given circles can be shrunk to zero radius (a point) or expanded to infinite radius (a line). Viète's approach, which uses simpler limiting cases to solve more complicated ones, is considered a plausible reconstruction of Apollonius' method. The method of van Roomen was simplified by Isaac Newton, who showed that Apollonius' problem is equivalent to finding a position from the differences of its distances to three known points. This has applications in navigation and positioning systems such as LORAN.
Later mathematicians introduced algebraic methods, which transform a geometric problem into algebraic equations. These methods were simplified by exploiting symmetries inherent in the problem of Apollonius: for instance solution circles generically occur in pairs, with one solution enclosing the given circles that the other excludes (Figure 2). Joseph Diaz Gergonne used this symmetry to provide an elegant straightedge and compass solution, while other mathematicians used geometrical transformations such as reflection in a circle to simplify the configuration of the given circles. These developments provide a geometrical setting for algebraic
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https://en.wikipedia.org/wiki/Optimum%20%22L%22%20filter
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The Optimum "L" filter (also known as a Legendre–Papoulis filter) was proposed by Athanasios Papoulis in 1958. It has the maximum roll off rate for a given filter order while maintaining a monotonic frequency response. It provides a compromise between the Butterworth filter which is monotonic but has a slower roll off and the Chebyshev filter which has a faster roll off but has ripple in either the passband or stopband. The filter design is based on Legendre polynomials which is the reason for its alternate name and the "L" in Optimum "L".
See also
Bessel filter
Elliptic filter
References
Second Edition.
Optimum “L” Filters: Polynomials, Poles and Circuit Elements by C. Bond, 2004
Notes on “L” (Optimal) Filters by C. Bond, 2011
Linear filters
Network synthesis filters
Electronic design
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https://en.wikipedia.org/wiki/NetWare%20Core%20Protocol
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The NetWare Core Protocol (NCP) is a network protocol used in some products from Novell, Inc. It is usually associated with the client-server operating system Novell NetWare which originally supported primarily MS-DOS client stations, but later support for other platforms such as Microsoft Windows, the classic Mac OS, Linux, Windows NT, Mac OS X, and various flavors of Unix was added.
The NCP is used to access file, print, directory, clock synchronization, messaging, remote command execution and other network service functions. It originally took advantage of an easy network configuration and a little memory footprint of the IPX/SPX protocol stack. Since 1991 the TCP/IP implementation is available.
Novell eDirectory uses NCP for synchronizing data changes between the servers in a directory service tree.
Technical information
The original IPX/SPX implementation was provided only for Novell NetWare platform and now is obsolete. The TCP/IP implementation uses TCP/UDP port 524 and relies on SLP for name resolution.
For NCP operation in IPX/SPX networks the bare IPX protocol was used with Packet Type field set to 17. On the workstation (client station) side the IPX socket number of 0x4003 was used, on the server side the socket number of 0x0451.
The NCP PDU has the following structure:
The NCP Type field determines the type of operation:
Individual requests are identified by the Sequence Number (modulo 256). The Connection Number identifies an individual client station connection on the server. Novell Netware servers of version up to 2.x supported up to 255 connections and the Connection Number occupied only 1 octet. Later it was extended to 2 octets. Task number has value 3 in requests and 1 in replies. The Data field starts with NCP Function number octet which distinguishes individual services.
The contents and the length of the rest of the Data field depends on the NCP Function.
Client-side implementations
Novell Client for Windows Vista from Novell.
Nov
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https://en.wikipedia.org/wiki/Operation%20Ruthless
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Operation Ruthless was the name of a deception operation devised by Ian Fleming in the British Admiralty during World War II, in an attempt to gain access to German Naval Enigma codebooks.
Background
With the help of their Polish allies, British codebreakers at Bletchley Park had considerable success in decoding the Enigma-enciphered traffic of the German air force, army and intelligence and counter-espionage service (Abwehr), but had made little progress with German naval messages. The methods of communicating the choice and starting positions, of Enigma's rotors, the indicator, were much more complex for naval messages. In 1940 Dilly Knox, the veteran World War I codebreaker, Frank Birch, head of Bletchley Park's German Naval Department, and the two leading codebreakers, Alan Turing and Peter Twinn knew that getting hold of the German Navy Enigma documentation was their best chance of making progress in breaking the code.
The Royal Navy's Operational Intelligence Centre (OIC) was a leading user of Ultra intelligence from Bletchley Park's decrypts. Lieutenant Commander Ian Fleming of the Admiralty's Naval Intelligence Division, who later wrote the James Bond novels, was the personal assistant to the Director of Naval Intelligence, Rear Admiral John Godfrey. Fleming liaised with the naval department at Bletchley Park, visiting about twice a month, and was well aware of this problem.
The plan
On 12 September 1940, Fleming wrote a note to Godfrey which read:
I suggest we obtain the loot by the following means:
1. Obtain from Air Ministry an air-worthy German bomber.
2. Pick a tough crew of five, including a pilot, W/T operator and word-perfect German speaker. Dress them in German Air Force uniform, add blood and bandages to suit.
3. Crash plane in the Channel after making S.O.S. to rescue service in P/L.
4. Once aboard rescue boat, shoot German crew, dump overboard, bring rescue boat back to English port.
In order to increase the chances of capturing
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https://en.wikipedia.org/wiki/Antibody%20testing
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Antibody testing may refer to:
Serological testing, tests that detect specific antibodies in the blood
Immunoassay, tests that use antibodies to detect substances
Antibody titer, tests that measure the amount of a specific antibody in a sample
Antibodies
Biological techniques and tools
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https://en.wikipedia.org/wiki/Archive%20site
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In web archiving, an archive site is a website that stores information on webpages from the past for anyone to view.
Common techniques
Two common techniques for archiving websites are using a web crawler or soliciting user submissions:
Using a web crawler: By using a web crawler (e.g., the Internet Archive) the service will not depend on an active community for its content, and thereby can build a larger database faster. However, web crawlers are only able to index and archive information the public has chosen to post to the Internet, or that is available to be crawled, as website developers and system administrators have the ability to block web crawlers from accessing [certain] web pages (using a robots.txt).
User submissions: While it can be difficult to start user submission services due to potentially low rates of user submissions, this system can yield some of the best results. By crawling web pages one is only able to obtain the information the public has chosen to post online; however, potential content providers may not bother to post certain information, assuming no one would be interested in it, because they lack a proper venue in which to post it, or because of copyright concerns. However, users who see someone wants their information may be more apt to submit it.
Examples
Google Groups
On 12 February 2001, Google acquired the usenet discussion group archives from Deja.com and turned it into their Google Groups service. They allow users to search old discussions with Google's search technology, while still allowing users to post to the mailing lists.
Internet Archive
The Internet Archive is building a compendium of websites and digital media. Starting in 1996, the Archive has been employing a web crawler to build up their database. It is one of the best known archive sites.
NBCUniversal Archives
NBCUniversal Archives offer access to exclusive content from NBCUniversal and its subsidiaries. Their NBCUniversal Archives website provides easy viewing
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