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Coherent Dwell
Coherence is, in general, a state or situation in which all the parts or ideas fit together well so that they form a united whole. More specifically, coherence, coherency, or coherent may refer to the following: Physics * Coherence (physics), an ideal property of waves that enables stationary (i.e. temporally and spatially constant) interference * Coherence (units of measurement), a derived unit that, for a given system of quantities and for a chosen set of base units, is a product of powers of base units with no other proportionality factor than one * Coherence time, the time over which a propagating wave (especially a laser or maser beam) may be considered coherent; the time interval within which its phase is, on average, predictable Mathematics * Coherence (philosophical gambling strategy), a concept in Bayesian statistics * Coherence (signal processing), a statistic that can be used to examine the relation between two signals or data sets * Coherence (statistics), a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coherence (physics)
Coherence expresses the potential for two waves to Wave interference, interfere. Two Monochromatic radiation, monochromatic beams from a single source always interfere. Wave sources are not strictly monochromatic: they may be ''partly coherent''. When interfering, two waves add together to create a wave of greater amplitude than either one (constructive Wave interference, interference) or subtract from each other to create a wave of minima which may be zero (destructive interference), depending on their relative phase (waves), phase. Constructive or destructive interference are limit cases, and two waves always interfere, even if the result of the addition is complicated or not remarkable. Two waves with constant relative phase will be coherent. The amount of coherence can readily be measured by the interference visibility, which looks at the size of the interference fringes relative to the input waves (as the phase offset is varied); a precise mathematical definition of the de ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coherence (programming Language)
Subtext is a moderately visual programming language and environment, for writing application software. It is an experimental, research attempt to develop a new programming language, programming model, called Example Centric Programming, by treating copied blocks as first class prototypes, for program structure. It uses live text, similar to what occurs in spreadsheets as users update cells, for frequent feedback. It is intended to eventually be developed enough to become a practical language for daily use. It is planned to be open software; the license is not yet determined. Subtext was created by Jonathan Edwards who submitted a paper on the language to OOPSLA. It was accepted as part of the 2005 conference. Environment Early video previews of the Subtext environment were released circa 2006, which demonstrated the semantics of Subtext programs, and the close integration with the Subtex environment and runtime. Subtext programs are declared and manipulated (or mutated) by add ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coherent Risk Measure
In the fields of actuarial science and financial economics there are a number of ways that risk can be defined; to clarify the concept theoreticians have described a number of properties that a risk measure might or might not have. A coherent risk measure is a function that satisfies properties of monotonicity, sub-additivity, homogeneity, and translational invariance. Properties Consider a random outcome X viewed as an element of a linear space \mathcal of measurable functions, defined on an appropriate probability space. A functional \varrho : \mathcal → \R \cup \ is said to be coherent risk measure for \mathcal if it satisfies the following properties: Normalized : \varrho(0) = 0 That is, the risk when holding no assets is zero. Monotonicity : \mathrm\; Z_1,Z_2 \in \mathcal \;\mathrm\; Z_1 \leq Z_2 \; \mathrm ,\; \mathrm \; \varrho(Z_1) \geq \varrho(Z_2) That is, if portfolio Z_2 always has better values than portfolio Z_1 under almost all scenarios then the risk of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coherence Time (communications Systems)
In communications systems, a communication channel may change with time. Coherence time is the time duration over which the channel impulse response is considered to be not varying. Such channel variation is much more significant in wireless communications systems, due to Doppler effects. Simple model In a simple model, a signal x(t) transmitted at time t_1 will be received as :y_(t) = x(t-t_1)*h_(t), where h_(t) is the channel impulse response (CIR) at time t_1. A signal transmitted at time t_2 will be received as :y_(t) = x(t-t_2)*h_(t). Now, if h_(t) - h_(t) is relatively small, the channel may be considered constant within the interval t_1 to t_2. Coherence time (T_c) will therefore be given by :T_c = t_2 - t_1. Relation with Doppler frequency Coherence time T_c is the time-domain dual of Doppler spread and is used to characterize the time-varying nature of the frequency dispersiveness of the channel in the time domain. The Maximum Doppler spread and coherence time are inve ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coherent Optical Module
Coherent optical module refers to a typically hot-pluggable coherent optical transceiver that uses coherent modulation ( BPSK/QPSK/ QAM) rather than amplitude modulation (RZ/ NRZ/ PAM4) and is typically used in high-bandwidth data communications applications. Optical modules typically have an electrical interface on the side that connects to the inside of the system and an optical interface on the side that connects to the outside world through a fiber optic cable. The technical details of coherent optical modules were proprietary for many years, but have recently attracted efforts by multi-source agreement (MSA) groups and a standards development organizations such as the Optical Internetworking Forum. Coherent optical modules can either plug into a front panel socket or an on-board socket. Coherent optical modules form a smaller piece of a much larger optical module industry. Electrical Interface Types There are multiple variants of the electrical interface of coherent optical m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coherence (music Theory)
In diatonic set theory, Rothenberg propriety is an important concept, lack of contradiction and ambiguity, in the general theory of musical scales which was introduced by David Rothenberg in a seminal series of papers in 1978. The concept was independently discovered in a more restricted context by Gerald Balzano, who termed it ''coherence''. "Rothenberg calls a scale 'strictly proper' if it possesses a generic ordering, 'proper' if it admits ambiguities but no contradictions, and 'improper' if it admits contradictions." A scale is strictly proper if all two step intervals are larger than any one step interval, all three step intervals are larger than any two step interval and so on. For instance with the diatonic scale, the one step intervals are the semitone (1) and tone (2), the two step intervals are the minor (3) and major (4) third, the three step intervals are the fourth (5) and tritone (6), the four step intervals are the fifth (7) and tritone (6), the five step interv ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coherence (linguistics)
Coherence in linguistics is what makes a text semantically meaningful. It is especially dealt with in text linguistics. Coherence is achieved through syntactic features such as the use of deictic, anaphoric and cataphoric elements or a logical tense structure, and semantic features such as presuppositions and implications connected to general world knowledge. Robert De Beaugrande and Wolfgang U. Dressler define coherence as a "continuity of senses" and "the mutual access and relevance within a configuration of concepts and relations". Thereby a textual world is created that does not have to comply to the real world. But within this textual world the arguments also have to be connected logically so that the reader/hearer can produce coherence. "Continuity of senses" implies a link between cohesion and the theory of Schemata initially proposed by F. C. Bartlett in 1932 which creates further implications for the notion of a "text". Schemata, subsequently distinguished into ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coherence (cognitive Science)
Coherence theories of truth characterize truth as a property of whole systems of propositions that can be ascribed to individual propositions only derivatively according to their coherence with the whole. While modern coherence theorists hold that there are many possible systems to which the determination of truth may be based upon coherence, others, particularly those with strong religious beliefs, hold that the truth only applies to a single absolute system. In general, truth requires a proper fit of elements within the whole system. Very often, though, coherence is taken to imply something more than simple formal coherence. For example, the coherence of the underlying set of concepts is considered to be a critical factor in judging validity for the whole system. In other words, the set of base concepts in a universe of discourse must first be seen to form an intelligible paradigm before many theorists will consider that the coherence theory of truth is applicable. History In mo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oracle Coherence
In computing, Oracle Coherence (originally Tangosol Coherence) is a Java-based distributed cache and in-memory data grid. It is claimed to be intended for systems that require high availability, high scalability and low latency, particularly in cases when traditional relational database management systems provide insufficient throughput, or insufficient performance. History Tangosol Coherence was created by Cameron Purdy and Gene Gleyzer, and initially released in December, 2001. Oracle Corporation acquired Tangosol Inc., the original owner of the product, in April 2007, at which point it had more than 100 direct customers. Tangosol Coherence was also embedded in a number of other companies' software products, some of which belonged to Oracle Corporation's competitors. Features Coherence provides mechanisms to integrate with other services using TopLink, Java Persistence API, Oracle Golden Gate and other platforms using APIs provided by Coherence. Coherence can be used to m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coherent (operating System)
Coherent is a clone of the Unix operating system for IBM PC compatibles and other microcomputers, developed and sold by the now-defunct Mark Williams Company (MWC). Historically, the operating system was a proprietary product, but it became Open-source software, open source in 2015, released under the BSD licenses, BSD-3-Clause license. Development Coherent was not Unix; the Mark Williams Company had no rights to either the Unix trademark or the AT&T Corporation, AT&T/Bell Labs source code. In the early years of its existence, MWC received a visit from an AT&T delegation looking to determine whether MWC was infringing on AT&T Unix property. The delegation included Dennis Ritchie, who concluded that "it was very hard to believe that Coherent and its basic applications were not created without considerable study of the OS code and details of its applications." However, he also stated that: Much of the operating system was written by alumni from the University of Waterloo: Tom ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coherence (software)
Parallels Desktop for Mac is a hypervisor providing hardware virtualization for Mac (computer), Mac computers. It is developed by Parallels (company), Parallels, a subsidiary of Corel. Parallels was initially developed for Macintosh systems with Intel processors, with version 16.5 introducing support for Macs with Apple silicon. Microsoft officially endorses the use of Parallels Desktop for running Windows 11 on Apple silicon Macs. History Released on June 15, 2006, it was the first software product to bring mainstream virtualization to Macintosh computers utilizing the Apple–Intel architecture (earlier software products ran PC software in an emulated environment). Its name initially was 'Parallels Workstation for macOS, Mac OS X', which was consistent with the company's corresponding Linux and Windows products. This name was not well received within the Mac community, where some felt that the name, particularly the term “workstation,” evoked the aesthetics of a Windows pr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
