User:John R. Brews/Articles

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  • Alexa Internet [r]: A subsidiary of Amazon.com that provides traffic data, global rankings and other information on 30 million websites world wide. [e]
  • Analytic-synthetic distinction [r]: A distinction used in philosophy to divide an ontology into two parts: an analytic part consisting of terms related by synonymy, and a synthetic part concerning connections between such terms and 'real' objects. [e]
  • Answers.com [r]: A web-based question-and-answers site that copies information from other web sites. [e]
  • Ask.com [r]: A question-answering web search engine owned and operated by Dublin, Ireland-based IAC Search & Media Europe, Ltd. [e]
  • Asymptotic gain model [r]: A formal expression for the gain of negative feedback amplifiers that can provide intuitive insight and often is easier to evaluate than a direct analysis of the gain. [e]
  • Atomic units [r]: A system of units convenient for atomic and molecular calculations. [e]
  • Biological computation [r]: The study of computational processes in biological systems [e]
  • Bipolar transistor [r]: A three-terminal semiconductor device used for switching and amplification. [e]
  • Bode plot [r]: A graph of the complex logarithm of the transfer function of a linear, time-invariant system plotted with a log-frequency axis. There are two plots: the Bode magnitude plot and the Bode phase plot, governing the real and the imaginary parts of the transfer function. [e]
  • Boolean algebra [r]: A form of logical calculus with two binary operations AND (multiplication, •) and OR (addition, +) and one unary operation NOT (negation, ~) that reverses the truth value of any statement. [e]
  • Cent (music) [r]: The logarithmic division of the equitempered semitone into 100 equal parts. It is therefore the 1200th root of 2, a ratio approximately equal to (1:1.0005777895). [e]
  • Centrifugal force [r]: A radially outward force experienced by an object moving in a curved path [e]
  • Centripetal force [r]: The force directed normal to the path of a moving body that enables the body to navigate the curvature of the path [e]
  • Clairaut's theorem [r]: A theorem describing the figure of the Earth as an oblate spheroid. [e]
  • Cognitive psychology [r]: The branch of cognitive science that deals with human mental processes involved in thinking, feeling and behaving. [e]
  • Comité International des Poids et Mesures [r]: An international committee set up to promote uniformity in units of measurement. [e]
  • Coriolis effect [r]: A disorientation caused by misinterpretation of rotational signals by the ear, important particularly to astronauts and pilots. [e]
  • Coriolis force [r]: An inertial force upon a moving object that is perpendicular to its velocity as that is seen from a rotating frame of reference, and also to the axis of rotation. [e]
  • Current mirror [r]: An electrical circuit designed to control a current through one active device by copying the current in another active device, thereby keeping the output current constant regardless of loading. [e]
  • Determinism [r]: A philosophical position that our acts are the consequences of the laws of nature and therefore the consequences of our acts are not our responsibility. [e]
  • Dilemma of determinism [r]: A moral quandary posed by a belief that events are determined by outside agency, placing human decisions outside moral responsibility [e]
  • Doppler effect [r]: Frequency changes of a wave due to relative motion between source and observer. [e]
  • Electronic band structure [r]: The very closely spaced energy levels available to electrons in solids, which are separated from each other by energy gaps. [e]
  • Elementary particle [r]: A particle that has no internal structure; that is, both theoretically and experimentally there are no constituent particles that combine to make it up. [e]
  • Envelope function [r]: A smooth curve outlining the extremes in amplitude of a rapidly varying function. [e]
  • Extended cognition [r]: The extension of mental processes and mind beyond the body to include aspects of the environment in which an organism is embedded and the organism's interaction with that environment [e]
  • Feedback [r]: The use of information from the monitoring of system performance either to modify or to maintain that performance. [e]
  • Fermi function [r]: The equilibrium occupancy of an energy level in a system of independent fermions at a fixed temperature. [e]
  • Foucault pendulum [r]: A pendulum demonstrating the Earth's rotation as it maintains its plane of motion independent of movement of its suspension attached to planet Earth. [e]
  • Frame of reference (physics) [r]: An observational set of coordinates tied to the motion of an observer, used to describe physical events and possibly including a measurement apparatus. [e]
  • Free will [r]: The intuition, or philosophical doctrine, that one can control one's actions or freely choose among alternatives. [e] Not originated by me, but greatly expanded and provided all sources.
  • General theory of relativity [r]: An explanation of the phenomena of gravity as an effect of masses upon the geometry of space and time [e]
  • Gyromagnetic ratio [r]: The constant of proportionality between the magnetic moment and angular momentum of an object. [e]
  • Hadron [r]: A composite particle made up of quarks bound together by the strong force, such as a meson, proton, or a neutron. [e]
  • Hard problem of consciousness [r]: The problem of finding an explanation for how physical phenomena acquire subjective characteristics becoming, for example, colors and tastes [e]
  • Holophrastic indeterminacy [r]: The view that there is more than one correct method of translating sentences that differ in their claims about the net import of entire sentences. [e]
  • Hybrid-pi model [r]: A circuit model used for analyzing the small-signal behavior of transistors. [e]
  • Idée fixe [r]: A preoccupation of mind held so firmly as to resist any attempt to modify it, a fixation [e]
  • Inertial forces [r]: Forces introduced to enable the use of the laws of motion in accelerating frames of reference, such as rotational frames [e]
  • Internal-external distinction [r]: A division of an ontology into an internal linguistic framework and external practical questions about the utility of that framework [e]
  • International Concert Pitch [r]: A standardization of pitch that sets the frequency of a simple tone at pitch A4 (the A above middle C) to be 440 Hz. [e]
  • Inertial frame of reference [r]: A frame of reference in which the laws of physics take their simplest form. [e]
  • Lepton [r]: A spin 1/2 elementary particle, such as an electron, muon or neutrino, that is not subject to the strong force. [e]
  • Liénard–Wiechert potentials [r]: Scalar and vector potentials that allow determination of exact solutions of the Maxwell equations for the electric field and magnetic flux density generated at an arbitrary location by an ideal point charge moving in a trajectory prescribed in advance (not calculated from any dynamical model). [e]
  • Logical determinism [r]: The philosophical view that because propositions about future events are true or false even before the events occur, the events that the true propositions refer to must happen necessarily [e]
  • Magnetic moment [r]: A vector property of an object that determines the torque it experiences in a magnetic flux density. [e]
  • Magnetization [r]: Magnetic moment per unit volume of a material, denoted M, defined in terms of the magnetic moments of its constituents by M=(1/V)Σj mj where the magnetic moment mj of the j-th constituent in the volume V is a vector property that determines the torque the object experiences in a magnetic field tending to align its moment with the field. [e]
  • Measurement in quantum mechanics [r]: The interpretation of measurement in quantum mechanics [e]
  • Mental causation [r]: The hypothetical possibility that the mind or mental acts can influence physical events [e]
  • Mereology [r]: The branch of philosophy that concerns the relation of wholes and their parts [e]
  • Meta-ontology [r]: What constitutes an ontology and its methods [e]
  • Metre (unit) [r]: Unit of length; one of the seven SI base units. [e]
  • MIDI (Musical Instrument Digital Interface) [r]: A digital encoding of music in which each note is assigned a numeric value with A4 (440 Hz; the A above middle C) given the number 69, and adjacent notes tuned according to equal temperament in the frequency ratio 21/12. Various codes allow selection of timbre and of sound envelope. [e]
  • Miller effect [r]: The increase in the equivalent input capacitance of an inverting voltage amplifier due to a capacitance connected between two gain-related nodes. [e]
  • Mind-body problem [r]: The philosophical and scientific consideration of the relation between conscious mental activity and the underlying physical plant that supports this activity, consisting primarily of the brain, but also involving various sensors throughout the body. [e] Begun with some paragraphs initially found in Brain.
  • Mode (electronics) [r]: A range of operation of an electrical device set by its bias condition or, when no signals are present, its quiescent or operating point. [e]
  • Model-dependent realism [r]: A philosophical position that all we can know about reality consists of networks of world pictures that explain observations by connecting them by rules to concepts defined in models. [e]
  • Model theory [r]: The study of the interpretation of any language, formal or natural, by means of set-theoretic structures. [e]
  • Moral responsibility [r]: A duty or obligation to behave in a 'good' manner and refrain from behaving in a 'bad' manner. [e]
  • MOS capacitor [r]: A two-terminal device consisting of three layers: a metal gate, a semiconducting body and a separating insulator, often an oxide. [e]
  • MOSFET [r]: A type of field-effect transistor with four electrical contacts and three layers: a metal top layer (connected to the gate contact),separated by an insulating layer (usually an oxide layer) from a semiconductor layer (connected to the body contact). The gate voltage switches "on" and "off" the electrical connection between a source and drain contact at the semiconductor surface. [e]
  • Norton's theorem [r]: An electrical network theorem explaining the replacement of a two-terminal portion of a linear circuit by a simplified circuit consisting of a current source, called the Norton source, in parallel with an impedance, called the Norton impedance. [e]
  • Note (music) [r]: An abstract representation of the pitch and duration of a tone used in music. [e]
  • Nuclear force [r]: The force holding assemblies of protons and neutrons together [e]
  • Nullor [r]: A theoretical network element with infinite gain useful for modeling circuits containing operational amplifiers [e]
  • Occam's razor [r]: Other things being equal—when several theories explain the same facts equally well, it is rational to prefer the most parsimonious of the theories. [e]
  • Ontological commitment [r]: A general term used in both philosophy and in information systems to refer to the essential elements of an ontology. [e]
  • Ontological pluralism [r]: The doctrine that there are different ways or modes of being [e]
  • Ontology (philosophy) [r]: The branch of philosophy that considers what things exist, and what existence implies. [e]
  • Order parameter [r]: A variable or field describing a collective behavior of a complex system, an ordering of components or subsystems on a macroscopic scale. [e]
  • Physical determinism [r]: A philosophical position that holds that all physical events occur as described by physical laws. [e]
  • Pitch (music) [r]: Perceived frequency of a sound or musical tone. [e] - - Didn't originate, but rewrote all but History and Physics sections
  • Pole splitting [r]: A form of frequency compensation used in an electronic amplifier to increase the stability of the amplifier and improve its step response at the cost of decreased speed. [e]
  • Quantifier variance [r]: A position in meta-ontology that claims there is no uniquely best ontological language with which to describe the world [e]
  • Quantum electrodynamics [r]: A relativistic theory of the interaction between electrically charged bodies based upon the exchange of photons, the quanta of the electromagnetic field. [e]
  • Relative permeability [r]: A factor describing magnetizability as a proportionality between magnetic flux density and magnetic field in a magnetic material or medium. [e]
  • Return ratio [r]: For a dependent source in a linear electrical circuit, the negative of the ratio between the current (voltage) returned to the site of a dependent source and the current (voltage) of a replacement independent source. [e]
  • Rydberg constant [r]: A theoretical constant related to the spectrum of atomic hydrogen defined by the Bohr theory of the atom as: R = mee4/(4πℏ3 c[μ0 c2/()]2 . [e]
  • Schottky diode [r]: A two-terminal electrical device consisting of conductive gate (for example, a metal) on top of a semiconductor body used for switching, rectification and photo-detection [e]
  • Self-organizing system [r]: A system that acquires new structure based upon the collective actions of a large number of autonomous subsystems. [e]
  • Semiconductor [r]: A substance (usually a solid) with electrical conductivity intermediate between metals and insulators. [e]
  • Semiconductor diode [r]: Two-terminal device that conducts current in only one direction, made of two or more layers of material, of which at least one is a semiconductor. [e]
  • Semitone (music) [r]: The interval or step in pitch between adjacent notes in a particular tuning of the chromatic musical scale called equal temperament. [e]
  • Speed of light [r]: A physical constant c describing the speed of electromagnetic radiation in vacuum. In the International System of Units the metre is the distance light travels in classical vacuum in 1/c seconds, using the defined value c = c0299  792  458 m/s (exact). [e]
  • Spectrum (linear operator) [r]: A set of values {λ} characteristic of an operator O mapping a Banach space into itself such that O xλ = λ xλ for some nonzero vectors xλ. [e]
  • Standard argument against free will [r]: An argument proposing a conflict between the possibility of free will and the postulates of determinism and indeterminism. [e]
  • Standard Model [r]: A mathematical theory that describes the weak, electromagnetic and strong interactions between leptons and quarks, the basic particles of particle physics. [e]
  • Step response [r]: The time behavior of a system's output when its input changes rapidly from zero to a finite value. [e]
  • Subjective-objective dichotomy [r]: The philosophical separation of the world into objects (entities) which are perceived or otherwise presumed to exist as entities, by subjects (observers). [e]
  • Timbre [r]: That attribute of auditory sensation in terms of which a listener can judge that two sounds similarly presented and having the same loudness and pitch are dissimilar [e]
  • Tone (music) [r]: The sound produced by a musical instrument while playing a particular musical note. [e]
  • Thévenin's theorem [r]: An electrical network theorem explaining the replacement of a two-terminal portion of a linear circuit by a simplified circuit consisting of a voltage source, called the Thévenin voltage source, in series with an impedance, called the Thévenin impedance. [e]
  • Transistor [r]: A semiconductor device that allows a signal at its input terminal(s) (usually a current or a voltage) to control an output signal at its output terminal(s), acting either as a switch activated by the input signal or as an amplifier for the input signal. [e]
  • Two-port network [r]: An electrical network with two ports, useful for simplifying linear electrical circuits [e]
  • Vacuum (classical) [r]: The term classical vacuum as used in classical electromagnetism and in the definition of the SI units refers to an ideal reference medium devoid of all particles, with ideal properties. These ideal properties include: independence from field strengths, direction, frequency, or polarization, and from temperature. [e]
  • Vacuum (partial) [r]: A realizable vacuum with a gaseous pressure that is much less than atmospheric. [e]
  • Vacuum (quantum electrodynamic) [r]: The term quantum electrodynamic vacuum, or QED vacuum, refers to the ground state of the electromagnetic field, which is subject to fluctuations about a dormant zero average-field condition. [e]
  • Venn diagram [r]: A visual representation of inclusion relations of sets or logical propositions by arrangements of regions in the plane. [e]
  • Vibrational spectrum [r]: The set of frequencies exhibited by regular, periodic motions of the parts of a mechanical system relative to one another that persist once excited without requiring an external driving agency. [e]
  • Widlar current source [r]: a modification of the basic two-transistor current mirror that incorporates an emitter degeneration resistor for only the output transistor, enabling the current source to generate low currents using only moderate resistor values and therefore a small area [e]
  • Wikia [r]: A website intended to help people create wikis devoted to their particular interests, where they can meet others that share that interest. [e]
  • Zermelo-Fraenkel axioms [r]: One of several possible formulations of axiomatic set theory. [e]