In certain classical music forms, a modulation can have structural significance. In sonata form, for example, a modulation divides the first subject from the second subject. Frequent changes of key characterize the development section of sonatas. Moving to the subdominant is a standard practice in the trio section of a march in a major key, while a minor march will move to the relative major. Changes of key may also represent changes in mood; many composers associate certain keys with specific emotional content, but in general, major keys are cheerful or heroic, while minors are sad and somber. Moving from ...

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Modulation music, Modulation music - Types of modulation, Modulation music - Common chord modulation, Modulation music - Enharmonic modulation, Modulation music - Common-tone modulation, Modulation music - Chromatic modulation, Modulation music - Phrase direct abrupt modulation, Modulation music - Sequential modulation rosalia, Modulation music - Common modulations, Modulation music - Significance of modulation, Modulation music - Other types of modulation

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Module file, Module file - Modules, Module file - Popular formats, Module file - Software module file players and converters, Module file - Hardware module file players

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There are several different types of modulation -- (these) modulations may be prepared or unprepared, smooth or abrupt. It is smoother to modulate to more closely related keys than to keys further away. Closeness is determined by the number of notes in common between keys, which provides more possible pivot chords, and their closeness on the circle of fifths. A modulation is often completed by a cadence in the new key, which helps to establish it. Brief modulations are often considered tonicizations. See also:

Modulation music, Modulation music - Types of modulation, Modulation music - Common chord modulation, Modulation music - Enharmonic modulation, Modulation music - Common-tone modulation, Modulation music - Chromatic modulation, Modulation music - Phrase direct abrupt modulation, Modulation music - Sequential modulation rosalia, Modulation music - Common modulations, Modulation music - Significance of modulation, Modulation music - Other types of modulation

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Any form of digital modulation necessarily uses a finite number of distinct signals to represent digital data. In the case of PSK, a finite number of phases are used. In the case of FSK, a finite number of frequencies are used. In the case of ASK, a finite number of amplitudes are used. This is very similar to pulse code modulation Each of these phases, frequencies or amplitudes are assigned a unique pattern of binary bits. Usually, each phase, frequency or amplitude encodes an equal number of bits. This number of bits comprises th ...

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Modulation, Modulation - Analog modulation techniques, Modulation - Digital modulation techniques, Modulation - Pulse modulation, Modulation - Miscellaneous techniques

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As with other modulation indices, in AM this quantity indicates by how much the modulated variable varies around its unmodulated level. For FM, it relates to the variations in the frequency of the carrier signal: With a tone-modulated FM wave, if the modulation frequency is held constant and the modulation index is increased, the (non-negligible) bandwidth of the FM signal increases, but the spacing between spectra stays the same. If the frequency deviation is held constant and the modulation index increased, the bandwidth stays rou ...

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Frequency modulation, Frequency modulation - Applications in radio, Frequency modulation - Theory, Frequency modulation - Modulation Index

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As with other modulation indices, in PM this quantity indicates by how much the modulated variable varies around its unmodulated level. For PM, it relates to the variations in the phase of the carrier signal: h = Δθ, where Δθ is the peak phase deviation. Compare to the modulation index for frequency modulation. ...

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Phase modulation, Phase modulation - Theory, Phase modulation - Modulation Index

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The zero module is the only one with length 0. Modules with length 1 are precisely the simple modules. For every finite-dimensional vector space (viewed as a module over the base field), the length and the dimension coincide. The length of the cyclic group Z/nZ (viewed as a module over the integers Z) is equal to the number of prime factors of n, with ...

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Length of a module, Length of a module - Definition, Length of a module - Examples, Length of a module - Facts

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Amplitude modulation (AM) is a form of modulation in which the amplitude of a carrier wave is varied in direct proportion to that of a modulating signal. (Contrast this with frequency modulation, in which the frequency of the carrier is varied; and phase modulation, in which the phase is varied.) AM is commonly used at radio frequencies and was the first method used to broadcast commercial radio. The term "AM" is sometimes used generically to refer to the AM broadcast (mediumwave) band (see AM radio). Ampli ...

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Amplitude modulation - Applications in radio
Amplitude modulation - AM vs. FM
Amplitude modulation - Forms of AM Amplitude modulation - Example
Amplitude modulation - A more general example
Amplitude modulation - Modulation index Amplitude modulation - Amplitude modulator designs
Amplitude modulation - Circuits Amplitude modulation - Low level Amplitude modulation - High level

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The first U.S.-built component of the International Space Station, a cylinder shaped connecting module with six passageways, or nodes, named Unity, was the primary cargo of Space Shuttle mission STS-88, launched in December 1998 as the first mission dedicated to assembly of the station. The Unity connecting module laid a foundation for all future U.S. International Space Station modules with six berthing ports, one on each side, to which future modules will be attached. Built by The Boeing Company at a manufacturing facility at ...

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Unity Module - Specifications

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A Conditional Access Module (CAM) is an electronic device, usually incorporating a slot for a smart card, which gives a DVB television or set-top box with the appropriate hardware the facility to decrypt scrambled programmes. They are normally used with direct broadcast satellite services, although the UK digital terrestrial pay TV supplier Top Up TV also uses CAMs. Some encryption systems for which CAMs are available are Nagravision, Viaccess, Mediaguard and Irdeto. NDS Videoguard encryption, the preferred choice of Sky Digita ...

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Let M be a (left or right) module over some ring R. Given a chain of submodules of M of the form we say that n is the length of the chain. The length of M is defined to be the largest length of any of its chains. If no such largest length exists, we say that M has infinite length. ...

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Length of a module, Length of a module - Definition, Length of a module - Examples, Length of a module - Facts

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Finitely generated. A module M is finitely generated if there exist finitely many elements x1,...,xn in M such that every element of M is a linear combination of those elements with coefficients from the scalar ring R. Free. A free module is a module that has a basis, or equivalently, one that is isomorphic to a direct sum of copies of the scalar ring R. These are the modules that behave very much like vector spaces. Projective. Projective modules are direct summands of fre ...

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Module mathematics, Module mathematics - Motivation, Module mathematics - Definition, Module mathematics - Examples, Module mathematics - Submodules and homomorphisms, Module mathematics - Types of modules, Module mathematics - Relation to representation theory, Module mathematics - Generalizations

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If the signal to be transmitted is which is restricted in amplitude to be and the sinusoidal carrier is where fc is the carrier's base frequency in hertz and A is an arbitrary amplitude, the carrier will be modulated by the signal as in where, f(t) = fc + fΔx ...

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Frequency modulation, Frequency modulation - Applications in radio, Frequency modulation - Theory, Frequency modulation - Modulation Index

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The modules over fields are vector spaces. A vector space is indecomposable if and only if its dimension is 1. So every vector space is a direct sum of indecomposable ones (with infinitely many summands if the dimension is infinite). The modules over the ring of integers Z are the abelian groups. An abelian group is indecomposable if and only if it is isomorphic to Z or to a factor group of the form Z/pnZ for some prime number p and some positive integer n. Every finit ...

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Indecomposable module, Indecomposable module - Examples, Indecomposable module - Facts

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Projective module - Direct summands of free modules. The easiest characterisation is as a direct summand of a free module. That is, a module P is projective provided there is a module Q such that the direct sum of the two is a free module F. From this it follows that we can think of P as a kind of projection in F: the module endomorphism in F that is the identity on P and 0 on Q is an idempotent matrix. See also:

Projective module, Projective module - Definitions, Projective module - Direct summands of free modules, Projective module - Lifting property, Projective module - Vector bundles and locally free modules, Projective module - Facts

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More formally, a left module Q over the ring R is injective if it satisfies one (and therefore all) of the following equivalent conditions: If Q is a submodule of some other left R-module M, then there exists another submodule K of M such that M is the internal direct sum of Q and K, i.e. Q + K = M and Q ∩ K = {0}. If X is a submodule of the left R-module Y and g : X → Q ...

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Injective module, Injective module - Definition, Injective module - Examples, Injective module - Facts, Injective module - Generalization

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We give the construction first in these two cases, under the assumption that we have only two objects. Then we generalise to an arbitrary family of arbitrary modules. The key elements of the general construction are more clearly identified by considering these two cases in depth. Direct sum of modules - Construction for two vector spaces. Suppose V and W are vector spaces over the field K. We can turn the cartesian product V × W into a vector space over K by defin ...

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Direct sum of modules, Direct sum of modules - Construction for vector spaces and abelian groups, Direct sum of modules - Construction for two vector spaces, Direct sum of modules - Construction for two abelian groups, Direct sum of modules - Construction for an arbitrary family of modules, Direct sum of modules - Properties, Direct sum of modules - Internal direct sum, Direct sum of modules - Categorical interpretation, Direct sum of modules - Direct sum of modules with additional structure, Direct sum of modules - Direct sum of Banach spaces, Direct sum of modules - Direct sum of Hilbert spaces

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Suppose that the signal to be sent, the modulating signal with frequency ωm and phase φm, is , and the carrier onto which the signal is to be modulated is . Then the modulated signal, , which shows how m(t) modulates the phase. Clearly, it could also be viewed as a change to the frequency of the signal and PM can be considered a special case of FM where the carrier frequency modulation is th ...

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Phase modulation, Phase modulation - Theory, Phase modulation - Modulation Index

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As with other modulation indices, in AM, this quantity, also called modulation depth, indicates by how much the modulated variable varies around its 'original' level. For AM, it relates to the variations in the carrier amplitude and is defined as: . So if h = 0.5, the carrier amplitude varies by 50% above and below its unmodulated level, and for h = 1.0 it varies by 100%. Modulation depth greater than 100% is generally to be avoided - practical transmitter systems will usually incorporate some ...

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Amplitude modulation, Amplitude modulation - Applications in radio, Amplitude modulation - AM vs. FM, Amplitude modulation - Forms of AM, Amplitude modulation - Example, Amplitude modulation - A more general example, Amplitude modulation - Modulation index, Amplitude modulation - Amplitude modulator designs, Amplitude modulation - Circuits, Amplitude modulation - Low level, Amplitude modulation - High level

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Amplitude modulation - Circuits. A wide range of different circuits have been used for AM, but one of the simplest circuits uses anode or collector modulation applied via a transformer. While it is perfectly possible to create good designs using solid-state electronics, valved (tube) circuits are shown here. In general, valves are able to easily yield RF powers far in excess of what can be achieved using solid state. Most high-power broadcast stations still use valves. Modulation circuit designs can be broadly divided into low and high l ...

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Amplitude modulation, Amplitude modulation - Applications in radio, Amplitude modulation - AM vs. FM, Amplitude modulation - Forms of AM, Amplitude modulation - Example, Amplitude modulation - A more general example, Amplitude modulation - Modulation index, Amplitude modulation - Amplitude modulator designs, Amplitude modulation - Circuits, Amplitude modulation - Low level, Amplitude modulation - High level

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