Refimprove date December 2009 For any complex number written in polar form such as r e sup i sup , the phase factor is the exponential part, i.e. e sup i sup . As such, the term phase factor is similar to the term phasor , although the former term is more common in quantum mechanics. This phase factor is itself a complex number of absolute value 1. The variable appearing in such an expression is generally referred to as the phase waves phase . Multiplying the equation of a plane wave A e sup i k r t sup by a phase factor phase shift shifts the phase of the wave by math text e i theta A text e i left mathbf k cdot mathbf r omega t right A text e i left mathbf k cdot mathbf r omega t theta right math . In quantum mechanics , a phase factor is a complex coefficient e sup i sup that multiplies a Bra ket notation ket math psi rangle math or Bra ket notation bra math langle phi math . It does not, in itself, have any physical meaning, since the introduction of a phase factor does not change the expectation values of a Hermitian operator . That is, the values of math langle phi A phi rangle math and math langle phi e i theta A e i theta phi rangle math are the same. ref harvtxt Messiah 1999 p 296 ref However, differences in phase factors between two interacting quantum state s can sometimes be measurable such as in the Berry phase and this can have important consequences. In optics , the phase factor is an important quantity in the treatment of Interference wave propagation interference . See also Berry phase Bra ket notation Euler s formula Phasor Plane wave Notes reflist References citation last Messiah first Albert authorlink Albert Messiah title Quantum Mechanics publisher Dover year 1999 isbn 0 486 40924 4 DEFAULTSORT Phase Factor Category Quantum mechanics Category Information theory Category Quantum information science Category Notation zh ... more details
File Tipton Phase sites HRoe 2010.jpg thumb right 300px The Tipton Phase and some of its associated sites The Tipton Phase is an archaeological phase in southwestern Tennessee of the Late Mississippian culture . Other contemporaneous groups in the area include the Parkin Archeological State Park Culture of the Parkin Phase Parkin Phase , Walls Phase , Menard Hodges Site Menard Phase , and the Nodena Phase . The Tipton Phase is the last prehistoric people to inhabit the area before the arrival of Europeans. It is located directly across the Mississippi River from the people of the Nodena Phase and directly north of the Walls Phase. During the early 1540s the Hernando de Soto Expedition passed through the area, stopping at many villages in the area. ref cite book editors David H. Dye and Sheryl Ann Cox author Smith, Gerald P. title Towns and Temples Along the Mississippi article The Walls Phase and its Neighbors year 1990 publisher University of Alabama Press isbn 0 8173 0455 X pages 165 168 ref The phase itself is named for Tipton County, Tennessee . Culture Settlement pattern Empty section date January 2011 Burial Empty section date January 2011 Pottery Main Mississippian culture pottery Stone Industry Empty section date January 2011 Chronological position Empty section date July 2010 References reflist Mississippian and related cultures Pre Columbian North America Category Middle Mississippian culture Category Indigenous peoples in the United States NorthAm native stub ... more details
Phase inversion means the swapping of the two poles of an alternating current source. A phase inversion is neither a time shift nor a phase shift, but simply a swap of plus and minus. For example, in a push pull power amplifier using vacuum tube s, the signal is most often split by a phase splitter aka phase inverter stage which produces two signals, one in phase , and the other out of phase , that is, phase inverted. These two signals then drive the two halves of the first push pull stage, which may be either the output stage in which case the phase splitter will be in between the driver stage if there is one and the output stage or the driver stage. The other common arrangements for driving a push pull stage are by using an isolation transformer to produce the split signals, or by using the in phase half of the first push pull stage to drive the other half. A common circuit using this last technique is the long tailed pair , often seen in television set s and oscilloscope s. In solid state electronics all of these techniques can be used, and phase inversion can also be produced by the use of NPN PNP complementary circuitry, which has no corresponding technique in vacuum tube designs. Phase inversion may occur with a random or periodic, symmetrical or non symmetrical waveform , although it is usually produced by the inversion of a symmetrical periodic Signalling telecommunication signal , resulting in a change in sign. A symmetrical periodic signal represented by f t A e sup j t sup , after phase inversion, becomes f sub 1 sub t Ae sup j t sup , where t is time , A is the magnitude of the vector, is angular frequency 2 f , where f is the frequency and 3.1416 and e 2.7183. The algebraic sum of f t and f sub 1 sub t will always be zero. FS1037C Category Electronics terms Category Wave mechanics electronics stub telecomm stub de Phasenumkehr ... more details
The boost phase is the portion of the flight of a ballistic missile or space vehicle during which the Booster rocketry booster and sustainer engines operate until it reaches peak velocity. This phase can take 3 to 4 minutes for a solid rocket shorter than for a Liquid rocket propellants liquid propellant rocket , the altitude at the end of this phase is 150 200 km, and the typical burn out speed is 7 km s. Boost phase intercept is a type of missile defense technology that would be designed to disable enemy missiles while they are still in the boost phase. Category Ballistic missiles Category Flight phases rocket stub ru ... more details
Unreferenced date December 2009 In superconductivity , the Josephson phase is the difference of the phase waves phase s of the quantum mechanical wave function in two superconducting electrodes forming a Josephson junction . For example, if the macroscopic wave functions math Psi 1 math and math Psi 2 math in superconductors 1 and 2 are given by math Psi 1 sqrt n s e i theta 1 math br math Psi 2 sqrt n s e i theta 2 math then the Josephson phase is math phi stackrel mathrm def theta 2 theta 1 math . DEFAULTSORT Josephson Phase Category Superconductivity Category Josephson effect ko ... more details
technical date January 2012 Unreferenced date December 2009 Wikify date December 2009 Burst phase is the first ten cycles of colour burst in the porch of the synchronising pulse in the PAL Phase Alternation Line broadcast television systems format. The frequency of this burst is 4.43361875 MHz, it is precise to half a cycle and is used as the reference frequency to synchronise the local oscillators of the colour decoder in a PAL television receiver. This colour burst is sometimes called the Swinging Burst , as it swings 45 degrees line by line hence the expression Phase alternating line . This swing is used to set the centre frequency of the colour reference oscillator in the decoder as mentioned above . The actual swing of the burst phase is used to identify a PAL and NON PAL line and produces what is known as the IDENT signal. DEFAULTSORT Burst Phase Category Television technology ... more details
merge from Phase detector characteristic discuss Talk Phase detector Merge phase detector characteristic date December 2011 Image Phase detectors.svg right frame Four phase detectors. Signal flow is from ... be made from NAND gates. On the middle left are two phase detectors adding feedback and removing one ... pump with a filter at its output. A phase detector or phase comparator is a frequency mixer ... the difference in phase between two signal inputs. It is an essential element of the phase locked loop PLL . Detecting phase differences is very important in many applications, such as electric motor ... s. Types Phase detectors for phase locked loop circuits may be classified in two types. ref Paul Horowitz ... always produces an output waveform, which must be filtered to control the phase locked loop voltage ... of the input and reference pulses, and produces a constant output proportional to phase difference ... voltage of the VCO. Analog phase detector The phase detector needs to compute the phase difference of its two input signals. Let be the phase of the first input and be the phase of the second. The actual input signals to the phase detector, however, are not and , but rather sinusoids such as sin and cos . In general, computing the phase difference would involve computing the arcsine and arccosine of each normalized input to get an ever increasing phase and doing a subtraction. Such an analog ... approximations. Assume that the phase differences will be small much less than 1 radian, for example ... alpha beta sin alpha cos beta sin beta cos alpha math The expression suggests a quadrature phase ... with phase shift networks. Two common implementations for multipliers are the double balanced diode ... common phase detector uses a single multiplier and a different trigonometric identity math sin ... over 2 math The first term provides the desired phase difference. The second term is a sinusoid at twice the reference frequency, so it can be filtered out. In the case of general waveforms the phase ... more details
Phase in sinusoidal functions or in waves has two different, but closely related meanings. One is the initial angle of a sinusoidal function at its Origin mathematics origin and is sometimes called phase ... Publishing isbn 0240807588 page 1499 ref Formula The phase of an Simple harmonic motion oscillation ... , math f , math , and math phi , math are constant parameters called the amplitude , frequency , and phase ... except for a displacement of math T 4 , math along the math t , math axis. The term phase ... t , math , in which case we would say the phase of math x t , math is math phi , math , and the phase ... say math x t , math and math y t , math have the same phase but are relative to their own specific ... t phi, , math or its modulo math 2 pi math value, is referred to as instantaneous phase , often just phase . Phase shift Image Phase shift.svg thumb Illustration of phase shift. The horizontal axis represents an angle phase that is increasing with time. Phase shift is any change that occurs in the phase of one quantity, or in the phase difference between two or more quantities. ref name Ballou2005 math phi , math is sometimes referred to as a phase shift or phase offset , because it represents a shift from zero phase. But a change in math phi , math is also referred to as a phase shift. For infinitely ... matrix phi , , math whose phase is now math phi begin matrix frac pi 2 end matrix . math It has been shifted by math begin matrix frac pi 2 end matrix math radians. Phase difference anchor Phase difference Image Sine waves same phase.svg thumb In phase waves Image Sine waves different phase.svg thumb Out of phase waves Image Phase shift illustration.png right thumb Left the real part of a plane wave moving from top to bottom. Right the same wave after a central section underwent a phase .... . Phase difference is the difference, expressed in electrical degrees or time, between two waves having ... that have the same frequency and different phases have a phase difference, and the oscillators are said ... more details
Two periodic functions periodic waveforms whose Phase waves phase difference is math tfrac 1 4 math of their output period are said to have a quadrature phase relationship. The term is also used in communication systems to describe one of the components of Orthogonality orthogonal decomposition. A composite signal described by its envelope and phase form math A t cdot sin 2 pi ft phi t math can be decomposed to an equivalent quadrature carrier IQ form as math I t cdot sin 2 pi ft Q t cdot cos 2 pi ft I t cdot sin 2 pi ft Q t cdot sin 2 pi ft begin matrix frac pi 2 end matrix math where math f , math represents a Carrier wave carrier frequency , and math I t stackrel mathrm def A t cdot cos phi t , math math Q t stackrel mathrm def A t cdot sin phi t . , math math A t , math and math phi t , math represent possible modulation of a pure carrier wave math sin 2 pi f t . , math The modulation alters the original math sin , math component of the carrier, and creates a new math cos , math component, as shown above. The component that is in phase with the original carrier is referred to as the direct or in phase component . The other component, which is always 90 math begin matrix frac pi 2 end matrix math radians Phase waves Phase difference out of phase , is referred to as the quadrature component . References reflist See also Phase waves In phase and quadrature I&Q components In phase and quadrature I&Q components Quadrature Quadrature amplitude modulation Constellation diagram Category Signal processing ... more details
DISPLAYTITLE G sub 0 sub phase Image Gray626.png thumb right 200px Many mammal cell biology cell s, such as this neuron , remain permanently or semipermanently in G sub 0 sub . The G sub 0 sub phase referred to the G zero phase or resting phase is a period in the cell cycle in which cells exist in a quiescence quiescent state. G sub 0 sub phase is viewed as either an extended G1 phase G sub 1 sub phase , where the cell is neither dividing nor preparing to divide, or a distinct quiescent stage that occurs outside of the cell cycle. ref name mad http www.madsci.org posts archives nov99 942335648.Cb.r.html Re Are the cells in the G0 g zero phase of mitosis really suspended? Erin Cram, Grad student, Molecular and Cellular Biology, University of CA, Berkeley. 1999. MadScience Network. Question ID 942142089.Cb. ref Some types of cells, such as neurons nerve and cardiomyocytes heart muscle cells , become quiescent when they reach maturity i.e., when they are Cellular differentiation terminally differentiated but continue to perform their main functions for the rest of the organism s life. Multinucleated muscle cells that do not undergo cytokinesis are also often considered to be in the G sub ... and a quiescent cell e.g., heart muscle cells and neurons , which will never enter the G sub 1 sub phase ... phase from a cell cycle checkpoint in the G1 phase G sub 1 sub phase , such as the restriction point ... s or nutrients. During the G sub 0 sub phase, the cell cycle machinery is dismantled and cyclin s and cyclin dependent kinase s disappear. Cells then remain in the G sub 0 sub phase until there is a reason ... and kidney, enter the G sub 0 sub phase semi permanently and can be induced to begin dividing again ... cells Although many cells in the G sub 0 sub phase may die along with the organism, not all cells that enter the G sub 0 sub phase are destined to die this is often simply a consequence of the cell ... G0 Phase Category Cell cycle es Fase G0 fa G0 pl Faza G0 pt Fase G0 ... more details
Infobox Game subject name Phase 10 image link Image Phase 10.jpg 300px image caption Cards used in Phase ... important cards knowing when to put down those cards matching, ordering bggid 1258 bggxrefs Phase 10 ... of Mattel. Phase 10 is based on a variant of rummy known as Liverpool Rummy , and is a member ... melds that a player must advance through in order to win. Phase 10 is Fundex s best selling product .... ref In December 2010, Fundex sold the rights to Phase 10 to Mattel, and now develops and markets ... of two players completing the last phase in the same hand, the player with the lowest score out of the tied ... where the tying players attempt to complete phase 10 or in variants, the last phase each player had ... down the current phase, and then rid their hand of remaining cards by discarding them on laid down ... any phase. More than one Wild card may be used in completing a Phase. Players can use as many Wild cards as they want as long as they use one natural card. Once a Wild card has been played in a Phase ... be used to complete any phase, including Phase 8 7 cards of one color . Any player can be skipped ... has already been skipped once to miss a second consecutive turn. Phases A phase is a combination of cards ... suggests, there are ten phases Phase 1 2 sets of 3 Phase 2 1 set of 3 1 run of 4 Phase 3 1 set of 4 1 run of 4 Phase 4 1 run of 7 Phase 5 1 run of 8 Phase 6 1 run of 9 Phase 7 2 sets of 4 Phase 8 7 cards of one color Phase 9 1 set of 5 1 set of 2 Phase 10 1 set of 5 1 set of 3 TWIST PHASES Phase 1 3 sets of 3 Phase 2 4 sets of 2 Phase 3 1 set of 5 1 run of 4 Phase 4 2 sets of 3 1 run of 3 Phase 5 1 set of 3 1 run of 6 Phase 6 2 runs of 4 Phase 7 1 run of 4 4 cards of 1 color Phase 8 1 run of 5 of 1 color Phase 9 8 cards of 1 color Phase 10 9 cards of 1 color Each player can make only one phase per hand. For instance, a run of 9 when the player is on Phase 4 cannot also count as Phase ... must be of the same color. Runs must stop at 12 and cannot wrap around to 1. All One Color Phase 8 ... more details
The hexatic phase is a phase that is between the solid and the isotropic liquid phases in two dimensional systems of particles. It is characterized by two order parameters a short range positional and a quasi long range orientational sixfold order. More generally, a hexatic is any phase that contains sixfold orientational order, in analogy with the nematic phase with twofold orientational order . The existence of the hexatic phase was proposed by John Michael Kosterlitz and David J. Thouless as well as Bertrand Halperin , David R. Nelson and A. P. Young in theoretical studies about melting in two dimensions. They proposed two phase transition s by binding of topological defect s dislocation and declination . The first transition occurs when the solid quasi long range positional order, long range orientational order undergoes a dislocation unbinding transition to the hexatic phase short range positional order, quasi long range orientational order . The second transition is the disclination unbinding transition which transforms the hexatic phase into an isotropic phase short range positional and orientational order . See also XY model Kosterlitz Thouless transition References J.M. Kosterlitz & D.J. Thouless Long Range Order and Metastability in Two Dimensional Solids and Superfluids . J. Phys. C 5, L124 1972 J.M. Kosterlitz & D.J. Thouless Ordering Metastability, and Phase Transitions in Two Dimensional Systems . J. Phys. C 6, 1181 1973 J.M. Kosterlitz The critical properties of the two dimensional XY model . J . Phys. C 7, 1046 1974 D.R. Nelson & J.M. Kosterlitz Universal Jump in the Superfluid Density of Two Dimensional Superfluids . Phys. Rev. Lett. 39, 1201 1205 1977 B.I. Halperin & D.R. Nelson Theory of Two Dimensional Melting . Phys. Rev. Lett. 41, 121 124 1978 D.R. Nelson & B.I. Halperin Dislocation mediated melting in two dimensions . Phys. Rev. B 19, 2457 2484 1979 ... Category Theoretical physics de hexatische Phase ... more details
Phase conjugation is a physical transformation of a wave field where the resulting field has a reversed propagation direction but keeps is amplitudes and phases. Description It is distinguished from Time Reversal Signal Processing by the fact that phase conjugation uses an holographic pumping holographic or parametric pumping whereas time reversal records and re emits the signal using transducer s ref name Brysev1998 http iopscience.iop.org 1063 7869 41 8 R03 A. P. Brysev et al., Wave phase conjugation of ultrasonic beams , Physics Uspekhi 1998 ref . Holographic pumping makes the incident wave interact with a pump wave of the same frequency and records its amplitude phase distribution. Then, a second pump wave reads the recorded signal and produces the conjugate wave. All those waves have the same frequency. In parametric pumping, the parameters of the medium are modulated by the pump wave at double frequency. The interaction of this perturbation with the incident wave will produce the conjugate wave. Both techniques allow an amplification of the conjugate wave compared to the incident wave ref name Brysev1998 . As in Time Reversal Signal Processing time reversal , the wave re emitted by a phase conjugation mirror will auto compensate the phase distortion and auto focus itself on its initial source, which can be a moving object ref name Brysev1998 . Phase conjugation methods exist in two main domains Acoustic phase conjugation Optical phase conjugation References Reflist See also Time Reversal Signal Processing commonscat Phase conjugation physics stub Category Wave mechanics fr Conjugaison de phase ... more details
Absolute phase refers to the phase waves phase of a waveform relative to some standard strictly speaking, phase is always relative . To the extent that this standard is accepted by all parties, one can speak of an absolute phase in a particular field of application. High fidelity In the realm of high fidelity reproduction of music, absolute phase refers the phase of the reproduced sound waves relative to the original sound waves, or to the relative phase of the various channels of stereo or multi channel reproduction. In most cases, it is actually a question of the polarity of the channels, i.e., an equal phase shift of 180 at all frequencies. Some audiophile s claim ref http www.gcaudio.com resources howtos absolutephase.html ref that reversing the polarities of all the channels simultaneously makes a perceptible difference in the sound quality, even though the relative phases of all the channels are preserved. Of course, since many musical instruments produce an amount of even order harmonic distortion and so do all practical loudspeakers, reversing the phase of the recorded signal would change the harmonic distribution between odd and even harmonics. Power electronics When dealing with power electronics , the phase of the voltage and current at various points in the system relative to one another are important. If the points of interest are widely separated in space, it is difficult to measure the relative phase. To solve this problem, the phase of the signals relative to absolute time UTC is measured using instruments relying on GPS . Comparison of two absolute phases in this sense allows the relative phase of distant signals to be computed. Ref http 64.233.179.104 search?q cache jvTG0D1EGaoJ www.arbiter.com ftp datasheets 1133a absolute phase.pdf absolute phase&hl de ... of the relative phase of the component frequencies. For examples of physical effects due to the phase ... H, et al. title Absolute phase phenomena in photoionization with few cycle laser pulses journal ... more details
Image Phase.001.png thumb A three phased sequence Archaeological phase and phasing refers to the logical reduction of Archaeological context context s recorded during excavation archaeology excavation to near contemporary archaeological horizon s that represent a distinct phase of previous land use. These often but not always will be a representation of a former land surface or occupation level and all Archaeological association associated features that were created into or from this point in time. A simplified description of phase would be that a phase is a view of a given Archaeological site as it would have been at time X . examples of phases that would have no associated occupation surfaces are phases of a site that have been horizontally truncated by later phases and only elements surviving of the truncated phase are those that were below ground level and the subsequent truncation at that time. Subsequent or earlier Phases are representations in changing occupation patterns and land use use over time. Phase is an extremely important concept in Archeological excavation archaeology excavation and post excavation work. Phasing is achieved by compiling smaller groups of contexts together ... are common. Phasing a site has a slightly different meaning to digging in phase .Digging in phase ... a latter physical stratigraphic relationship to them. Digging a site in phase is considered good ... analytical tool post excavation is the Harris matrix . Phase is sometimes termed differently depending on practitioner, examples include the term period but in the main phase is universal. Phase, component and focus A less rigorous term phase is sometimes used to denote a wider period represented ... of stratigraphy. An example of this use of Phase would be all the contexts between ... as the Saxon phase of the site. Note however this block of stratigraphy may have many phases within it as defined by the more rigorous definition of phase. See also Archaeological context Archaeological ... more details
Primary phase can refer to Materials science, see Liquidus temperature The Hitchhiker s Guide to the Galaxy Primary and Secondary Phases , a radio series disambig ... more details
Unreferenced date October 2006 Lead rewrite date December 2008 In theoretical physics , it is often important to consider gauge theory that admits many physical phenomena and phases , connected by phase transition s, in which the vacuum may be found. Gauge symmetry may be broken by the Higgs mechanism . In more general theories such as those relevant in string theory , there are often many Higgs field s that transform in different representations of the gauge group . If they transform in the adjoint representation or a similar representation, the original gauge symmetry is typically broken to a product of U 1 factors. Because U 1 describes electromagnetism including the Coulomb field, the corresponding phase is called a Coulomb phase . If the Higgs fields that induce the spontaneous symmetry breaking transform in other representations, the Higgs mechanism often breaks the gauge group completely and no U 1 factors are left. In this case, the corresponding vacuum expectation value s describe a Higgs phase . Using the representation of a gauge theory in terms of a D brane , for example D4 brane combined with D0 branes, the Coulomb phase describes D0 branes that have left the D4 branes and carry their own independent U 1 symmetries. The Higgs phase describes D0 branes dissolved in the D4 branes as instanton s. DEFAULTSORT Higgs Phase Category Quantum field theory particle stub ... more details
Orphan date October 2010 The R Phase is a phase found in Nickel titanium Nitinol . It is a martensitic phase in nature, but is not the martensite that is responsible for the shape memory and superelastic ... to the B19 monoclinic martensite phase, not the R phase. The R phase competes with martensite, often ... , or may be completely absent. The R phase to austenite transformation A R is reversible, with a very ... a very narrow temperature range , superelasticity. The R phase transformation from austenite occurs between 20 and 40 degrees C in most binary Nitinol alloys. The R phase was observed during ... year 1981 page 2101 . ref . The crystallography and thermodynamics of the R phase are now well understood ..., It must be the R phase whenever a device fails to perform as expected. Crystallographic structure and transformation The R phase is essentially a rhombohedral distortion of the cubic austenite phase ... every three austenitic cells. Thus the actual Crystal structure unit cell of the actual R phase structure ... . ref The R phase can be easily detected via X ray crystallography x ray diffraction or neutron diffraction , most clearly evidenced by a splitting of the 1 1 0 austenitic peak. While the R phase transformation is a first order transformation and the R phase is distinct and separate from martensite ... available superelastic alloys, however, the R phase transformational strain is only 0.25 to 0.50 ... transformation, with no evidence of R phase during the forward or reverse transformation cooling or heating , occurs in titanium rich alloys and fully annealed conditions. The symmetric R phase transformation occurs when the R phase intervenes between austenite and martensite on both heating and cooling ... R phase transformation is by far the more common transformational route Figure 4 . Here the R phase occurs during cooling, but not upon heating, due to the large hysteresis of the austenite ..., the R phase is no longer more stable than austenite, and thus the martensite reverts directly ... more details
Orphan date January 2012 The Abejas Phase , also known as the Late Archaic , is the fourth phase of the Tehuac n Valley matorral Tehuac n Valley of Mexico sequence, dating from 3825 2600 BC. Although the Tehuac n Valley matorral Tehuac n Valley sequence of phases has become one of the most famous phase sequences for any region in Mesoamerica , very few sites from these phases are known. Description Following the Ajuereado , El Riego , and the Coxcatlan phase , and followed by the Purron and Ajalpan phases , Abejas is the fourth of six phases. The Abejas phase population may have been twice as large as its preceding phase, Coxcatlan . This period is marked by the appearance of campsites and permanent settlements installed on river terraces, a noticeable decline in reliance on wild foods, domestication of plants maize, beans, squash , and the appearance of long obsidian blades ref cite book last Evans first Susan Toby title Ancient Mexico and Central America Archaeology and Culture History year 2044 publisher Thames & Hudson Ltd location London ref During this phase, agriculture supplies 25 of food requirements. Also during this phase, new material culture innovation arose such as split stitch basketry , stone bowls and jars. ref cite book last Darvill first Timothy title The Concise Oxford Dictionary of Archaeology year 2002 publisher Oxford University Press location USA ref Sites Sites associated with the Abejas phase include Coxcatlan Cave , San Marcos , Abejas , Purron Cave and an area near Chilac . However, Cueva Blanca is the only excavated site assigned to this time period. ref cite book last Richard and Macleod first Richard E. W. and Murdo J. title The Cambridge History of the Native Peoples of the Americas year 2000 publisher Cambridge University Press location Cambridge ref Other Information Although the evidence of Dogs in Mesoamerica dogs in mesoamerica dates ... America are from about 5,000 years ago from the Abejas phase . References references Category Mexico ... more details
other uses Image Focal stability.png thumb 300px right Phase space of a dynamical system with focal stability. In mathematics and physics , a phase space , introduced by Josiah Willard Gibbs Willard Gibbs in 1901, ref Findlay, Alex. The Phase Rule and its Applications. 3rd edition. pg 8. Longmans, Green ..., with each possible state of the system corresponding to one unique point in the phase space. For classical mechanics mechanical systems , the phase space usually consists of all possible values ... . A plot of position and momentum variables as a function of time is sometimes called a phase plot or a phase diagram . Phase diagram , however, is more usually reserved in the physical sciences for a diagram ..., which consists of pressure , temperature , and composition. In a phase space, every degrees of freedom ... space a one dimensional system is called a Phase line mathematics phase line , while a two dimensional system is called a phase plane . For every possible state of the system, or allowed .... In the end, the phase diagram represents all that the system can be, and its shape can easily elucidate qualities of the system that might not be obvious otherwise. A phase space may contain very many ... define co ordinates on phase space. More abstractly, in classical mechanics phase space is the cotangent ..., the phase space coordinates of the system at any given time are composed of all of the system .... Examples Low dimensions main phase line mathematics phase plane For simple systems, there may ... , math with the resulting one dimensional system being called a Phase line mathematics phase line , and the qualitative behaviour of the system being immediately visible from the phase line. The simplest ... growth model two equilibria, one stable, one unstable . The phase space of a two dimensional system is called a phase plane , which occurs in classical mechanics for a single particle moving ... of the phase portrait may give qualitative information about the dynamics of the system, such as the limit ... more details
Violin Phase , written by minimalism minimalist composer Steve Reich in October 1967, is an example of his phasing technique previously used in Piano Phase in which the music itself is created not by the instruments but by interactions of temporal variations on an original melody . Music of this kind is generally referred to as process music . In Violin Phase , two violins are recorded and played back, together at first. They are then made to go slowly out of sync by adding silence to one of the tapes. A new melody is formed by the interaction of the two out of sync instruments and is then accented by a third violin. This process is repeated with variations throughout the rest of the piece. Reich also arranged the piece for electric guitar and tape or 4 electric guitars . In this form the work was recorded as Electric Guitar Phase by Dominic Frasca . Steve Reich Category Minimalistic compositions Category Compositions by Steve Reich Category 1967 compositions Category Process music pieces classical composition stub fr Violin Phase ... more details
Expert subject Chemistry date February 2009 Third phase is the term for a stable emulsion which forms in a solvent extraction system when the original two phases aqueous and organic compound organic are mixed. The third phase can be caused by a detergent surfactant or a fine solid. While third phase is a term for an unwanted emulsion, a stable emulsion is wanted in emulsion polymerization all the things which can be used to make a stable emulsion for a latex synthesis can prove to encourgae a third phase to form. One term for the third phase found in PUREX plants is Chalk river unidentified deposits crud Chalk River Unknown Deposit . One common crud is formed by the reaction of zirconium salts from fission with degraded tributyl phosphate TBP . The TBP degrades into dibutyl hydrogen phosphate and then into butyl dihydrogen phosphate. The dibutyl hydrogen phosphate and the zirconium can form polymer ic solid which is very insoluble. References reflist Category Colloidal chemistry pt Terceira fase ... more details
File Walls Phase sites HRoe 2010.jpg thumb right 300px The Walls Phase and some of its associated sites The Walls Phase is an archaeological phase in southwestern Tennessee and northwestern Mississippi of the Late Mississippian culture . Chucalissa Indian Village is a Walls Phase mound and plaza complex located on a bluff overlooking the Mississippi River . Other contemporaneous groups in the area include the Parkin Archeological State Park Culture of the Parkin Phase Parkin Phase , Tipton Phase , Menard Hodges Site Menard Phase , and the Nodena Phase . The Walls Phase is the last prehistoric people to inhabit the Memphis area before the arrival of Europeans. ref cite book editors David H. Dye and Sheryl Ann Cox author Smith, Gerald P. title Towns and Temples Along the Mississippi article The Walls Phase and its Neighbors year 1990 publisher University of Alabama Press isbn 0 8173 0455 X pages 136 ref During the early 1540s the Hernando de Soto Expedition passed through the area, stopping at many villages along the way. It is thought that the Walls Phase may be the Province of Quizquiz tribe Quizquiz , a History of the Tunica people Tunican people encountered by de Soto on the banks of the Mississippi River. ref Cite book editor Charles H. McNutt title Prehistory of the Central Mississippi ... pattern The Walls Phase settlements consist of one large site , located at De Soto Park in Memphis ... Cox author Smith, Gerald P. title Towns and Temples Along the Mississippi article The Walls Phase and its Neighbors year 1990 publisher University of Alabama Press isbn 0 8173 0455 X pages 140 ref The phase itself is named for a site near the small hamlet of Walls, Mississippi . The Belle Meade Phase is located across the Mississippi River from the Walls Phase on its western bank, and the Tipton Phase is located directly north, also on the eastern bank of the Mississippi River. Burial Empty section ... of different vessel types and pastes have helped to define the phase from surrounding phases ... more details
One source date August 2009 DISPLAYTITLE G sub 1 sub phase The G sub 1 sub phase Gap 1 phase or post mitotic phase is a period in the cell cycle during interphase , before the S phase . For many cells, this phase is the major period of cell growth during its lifespan. During this stage new organelle s are being synthesized, so the cell requires both Protein Structural proteins structural proteins and enzyme s, resulting in a great amount of Protein biosynthesis protein synthesis and a high rate of metabolism in the cell. G sub 1 sub consists of four subphases Competence g1a Entry g1b Progression g1c Assembly g1d These subphases may be affected by limiting growth factor s, nutrient supply, temperature, and additional inhibiting factors. A rapidly dividing human cell which divides every 24 hours spends 9 hours in G sub 1 sub phase. ref name Lodish cite book author Lodish et al. title Molecular Cell Biology publisher W.H. Freeman and Co. edition 4th year 2000 ref A cell may pause in the G sub 1 sub phase before entering the S phase and enter a state of dormancy called the G0 phase G sub 0 sub phase . Most mammal ian cells do this. In order to divide, the cell re enters the cycle in S phase. ref name Lodish Status of the genome The DNA in a G sub 1 sub Ploidy Diploid diploid Eukaryote eukaryotic cell is 2n, meaning there are two sets of chromosome s present in the cell. The genetic material exists as chromatin and if it were coiled into chromosomes there would be no sister chromatid s. Ploidy Haploid and monoploid Haploid organisms such as some yeast s will be 1n and thus have only one copy of each chromosome present. Restriction point There is a restriction point present at the end of G sub 1 sub phase. This point is a series of safeguards to ensure the DNA is intact and that the cell ... of genes.These include genes which are responsible for DNA replication DNA synthesis proteins and S phase CDK proteins. ref name Lodish References reflist Cell cycle DEFAULTSORT G1 Phase Category ... more details
Unreferenced date December 2009 Modulation techniques Phase modulation PM is a form of modulation that represents information as variations in the instantaneous phase waves phase of a carrier wave . Unlike its more popular counterpart, frequency modulation FM , PM is not very widely used for radio transmissions. This is because it tends to require more complex receiving hardware and there can be ambiguity problems in determining whether, for example, the signal has changed phase by 180 or 180 . PM is used, however, in digital music synthesizers such as the Yamaha DX7 , even though these instruments are usually referred to as FM synthesizers both modulation types sound very similar, but PM is usually easier to implement in this area . Theory Image Phase Modulation.png thumb right 210 px An example of phase modulation. The top diagram shows the modulating signal superimposed on the carrier wave. The bottom diagram shows the resulting phase modulated signal. PM changes the phase angle of the complex ... carrier amplitude sin carrier frequency time phase shift This makes the modulated signal math y ... the phase the greater m t is at a point in time, the greater the phase shift of the modulated signal at that point. It can also be viewed as a change of the frequency of the carrier signal, and phase ... by the time derivative of the phase modulation. The mathematics of the spectral density spectral ... level. It relates to the variations in the phase of the carrier signal math h , Delta theta , math , where math Delta theta math is the peak phase deviation. Compare to the modulation index ... frequency control Modulation for a list of other modulation techniques Phase shift keying PSK , the digital version of PM Polar modulation Electro optic modulator for Pockel s Effect phase modulation for applying sidebands to a monochromatic wave DEFAULTSORT Phase Modulation Category Radio modulation ... Modulaci n de fase fr Modulation de phase ko it Modulazione di fase kk lv F zes ... more details
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