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The techniques used to transform massive datasets into a more suitable, or smaller, form for data analysis, while preserving the intrinsic characteristics of the data and minimizing the loss of accuracy. Data reduction is used for scientific…

A multidisciplinary field for analyzing large amounts of data—current and past (historical)—which are processed using tools and methods from statistics, applied mathematics, artificial intelligence, and computer programming, with the object of…

A means of storing a collection of data. Computer science is in part the study of methods for effectively using a computer to solve problems, or in other words, the entire process of determining exactly the problem to be solved. This process entails…

A data warehouse is an automated warehouse where related information is stored. Users can have access to large amounts of consistent, organized, and related information in a data warehouse. It is advantageous to have access to information from…

An alternative to the sequential, or von Neumann–based, model of computing, offering an inherently parallel metaphor. The dataflow concept is characterized by an orientation toward producing and consuming data values rather than updating storage…

An applied branch of decision theory. Decision analysis offers individuals and organizations a methodology for making decisions; it also offers techniques for modeling decision problems mathematically and finding optimal decisions numerically.…

A broad range of concepts which have been developed to both describe and prescribe the process of decision making, where a choice is made from a finite set of possible alternatives. Normative decision theory describes how decisions should be made in…

A device that recovers from a transmitted signal information that has been embedded in the signal by a process of modulation. The modification of a usually sinusoidal electrical carrier signal (or simply carrier) for the purpose of transmitting…

A mathematical operation performed on a function to determine the effect of a change in the value of the independent variable. Functions of one variable are considered in this article. For differentiation of functions of several variablesPartial…

A device which, in its simplest form, provides an output that corresponds to the number of pulses applied to its input. Types Counters may take many forms: geared mechanisms (water meters, odometers), relays (early telephone switch gear), vacuum…

Text, numerals, sound, or images (both moving and still) that are either stored or transmitted in a binary form and have potential use as evidence to prove a circumstance or event in a court of law. Binary refers to the electronic code made up of…

An Internet-based global naming and resolution system that provides for the precise identification, retrieval, and trading of digital items in the form of articles, books, images, bibliographies, supporting data, videos, charts, tables, audio, and…

A device for converting information in the form of combinations of discrete (usually binary) states or a signal to information in the form of the value or magnitude of some characteristics of a signal, in relation to a standard or reference. Most…

A four-port waveguide device (Fig. 1) in which an incoming wave at any one port (for example, A) appears at two others (C and D), but not at the fourth (B). This device has numerous applications in wave-guide networks such as microwave waveguides,…

For a polynomial f(x) = an xn + an−1 xn−1 + + a1 x + a0, the discriminant is given by the expression where x1, x2, …, xn are the roots of the equation f(x) = 0. There are n(n − 1)/2 terms (xi − xj)2 in the product corresponding to all possible…

A distributed system consists of a collection of autonomous computers linked by a computer network and equipped with distributed system software. This software enables computers to coordinate their activities and to share the resources of the system…

Programmable computers integrated with electrically powered machines that perform household chores. Domestic robots, also known as home or service robots, are essentially programmable computers integrated with electrically powered machines that…

A mathematical abstraction corresponding to an expression of the type βγ + δ∊ + · · · , in which the elements (dyad symbols) consist of two vector symbols in juxtaposition without the intervention of either the dot (·) or cross (×). Essentially a…

One of the solutions of an eigenvalue equation. A parameter-dependent equation that possesses nonvanishing solutions only for particular values (eigenvalues) of the parameter is an eigenvalue equation, the associated solutions being the…

One of the values of the parameter in an eigenvalue equation for which the equation has a solution. A linear eigenvalue equation is a parameter-dependent equation of the form (1) 1that possesses nonvanishing solutions, |v(n), only for particular…

A transmission network used to selectively modify the components of a signal according to their frequencies. In most cases a filter is used to enhance signals of desired frequencies while suppressing signals of undesired frequencies. An ideal filter…

That branch of electrical engineering dealing with the transmission and reception of information. Information can be transmitted over many different types of pathways, such as satellite channels, underwater acoustic channels, telephone cables, and…

Disturbance to the normal or expected operation of electrical or electronic devices, equipment, and systems. Electrical interference is sometimes called radio-frequency interference (RFI) or electromagnetic interference (EMI). Such disturbances may…

The connection of a specific circuit (called the load) to another circuit. Illustrationa shows a source of electrical energy (S), a coupling circuit (C), and a load (L). In power transmission, S is the generator of the power plant, C represents…

Interfering and unwanted currents or voltages in an electrical device or system. Electrical noise, or simply noise, has a significant effect on the design and operation of almost all electrical and optical systems which are used to communicate or…