WordNet
- distortion that occurs when the output signal does not have a linear relation to the input signal (同)amplitude distortion
- a change (usually undesired) in the waveform of an acoustic or analog electrical signal; the difference between two measurements of a signal (as between the input and output signal); "heavy metal guitar players use vacuum tube amplifiers to produce extrem
- the act of distorting something so it seems to mean something it was not intended to mean (同)overrefinement, straining, torture, twisting
- the mistake of misrepresenting the facts
- a change for the worse (同)deformation
- designating or involving an equation whose terms are not of the first degree
PrepTutorEJDIC
- 〈U〉(話・真実・事実などを)ゆがめること,曲げて伝えること / 〈U〉(形の)ゆがみ,ねじれ;〈C〉ゆがんだ(ねじれた)もの / (光の)ひずみ,収差
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出典(authority):フリー百科事典『ウィキペディア(Wikipedia)』「2014/01/30 19:10:56」(JST)
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Nonlinear distortion is a term used (in fields such as electronics, audio and telecommunications) to describe the phenomenon of a non-linear relationship between the "input" and "output" signals of - for example - an electronic device.
Model[edit]
For many devices, a linear model is accurate only for small signal levels. For example, at 2 volts input, a typical audio amplifier might put out 20 V, meaning the linear gain is 10 V/V. For 3 V input, it might then output 30 V. However, the model implies that at 50 V input it would produce 500 V, which is not possible with most amplifiers.
Mathematically, the input-output relationship of many devices should be described by a polynomial or Taylor series, as shown below.
For larger values of u, the higher order coefficients such as and come into play.
Effects of nonlinearity[edit]
Nonlinearity can have several effects, which are unwanted in typical situations. The term for example would, when the input is a sine wave with frequency , result in an extra sine wave at , as shown below.
In certain situations, this spurious signal can be filtered away because the "harmonic" lies far outside the frequency range used, but in cable television, for example, third order distortion could cause a 200 MHz signal to interfere with the regular channel at 600 MHz.
Nonlinear distortion applied to a superposition of two signals at different frequencies causes the circuit to act as a frequency mixer, creating intermodulation distortion.
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English Journal
- Thermodynamic investigation by heat capacity measurements of ferrimagnetic A2Mn[Mn(CN)6] (A=K, Rb, Cs) Prussian blue compounds.
- Kawamoto Y, Yamashita S, Yoshimoto R, Nakazawa Y, Dasilva JG, Kareis CM, Miller JS.Author information Department of Chemistry, Graduate School of Science, Osaka University, Machikaneyama 1-1, Toyonaka, Osaka 560-0043, Japan.AbstractHeat capacity measurements of a new series of Prussian blue analogs of A2Mn[Mn(CN)6] (A=K, Rb, Cs) composition were performed using thermal relaxation calorimetry. The Cs compound has a face-centered cubic structure with a linear Mn-C≡N-Mn linkage, while the monoclinic Rb and K compounds have nonlinear Mn-C≡N-Mn linkages. For all of the compounds, large broad thermal anomalies associated with magnetic transitions were observed in the temperature dependence of the heat capacity. The systematic changes in the heat capacity for the three compounds under magnetic fields of up to 7 T were found to be consistent with ferrimagnetic ordering with large spontaneous magnetization. Although the peak temperatures were slightly lower than reported values obtained by magnetic susceptibility measurements, the magnetic entropy was evaluated to be 22.0 ± 2.5 J K(-1) mol(-1). This value is consistent with an entropy of Rln12 corresponding to full entropy of one low-spin and one high-spin Mn(II) ion in the formula unit, though some ambiguity remains in lattice estimation. Broadening of the peak width of the magnetic heat capacity divided by the temperature was observed as the size of the alkali ions decreased from Cs to K. This behavior is consistent with an increase in the lattice distortion produced by the bending of the C≡N-Mn angles.
- Journal of physics. Condensed matter : an Institute of Physics journal.J Phys Condens Matter.2014 Jan 8;26(1):016001. doi: 10.1088/0953-8984/26/1/016001. Epub 2013 Nov 22.
- Heat capacity measurements of a new series of Prussian blue analogs of A2Mn[Mn(CN)6] (A=K, Rb, Cs) composition were performed using thermal relaxation calorimetry. The Cs compound has a face-centered cubic structure with a linear Mn-C≡N-Mn linkage, while the monoclinic Rb and K compounds have nonl
- PMID 24263378
- Cone dystrophy with "supernormal" rod ERG: psychophysical testing reveals comparable rod and cone temporal sensitivity losses with no gain in rod function.
- Stockman A, Henning B, Michaelides M, Moore AT, Webster AR, Cammack J, Ripamonti C.Author information Institute of Ophthalmology, University College London, 11-43 Bath Street, London, EC1V 9EL, United Kingdom.AbstractPurpose: We report a psychophysical investigation of five observers with the retinal disorder "cone dystrophy with supernormal rod ERG", caused by mutations in the gene KCNV2 that encodes a voltage-gated potassium channel found in rod and cone photoreceptors. We compare losses for rod- and for cone-mediated vision to further investigate the disorder and to assess whether the supernormal ERG is associated with any visual benefit. Methods: L-cone, S-cone and rod temporal acuity (critical flicker fusion frequency-cff) was measured as a function of target irradiance; L-cone temporal contrast-sensitivity was measured as a function of temporal frequency. Results: Temporal acuity measures reveal that losses for vision mediated by rods, S-cones and L-cones are roughly equivalent. Further, the gain in rod function implied by the supernormal ERG provides no apparent benefit to near-threshold rod-mediated visual performance. The L-cone temporal contrast-sensitivity function in affected observers is similar in shape to the mean normal function but only after the mean function has been compressed by halving the logarithmic sensitivities. Conclusions: The name of this disorder is potentially misleading because the comparable losses found across rod and cone vision suggest that the disorder is a generalized cone-rod dystrophy. Temporal acuity and temporal contrast-sensitivity measures are broadly consistent with the defect in the voltage-gated potassium channel producing a nonlinear distortion of the photoreceptor response but after otherwise normal transduction processes.
- Investigative ophthalmology & visual science.Invest Ophthalmol Vis Sci.2013 Dec 26. pii: iovs.13-12919v1. doi: 10.1167/iovs.13-12919. [Epub ahead of print]
- Purpose: We report a psychophysical investigation of five observers with the retinal disorder "cone dystrophy with supernormal rod ERG", caused by mutations in the gene KCNV2 that encodes a voltage-gated potassium channel found in rod and cone photoreceptors. We compare losses for rod- and for cone-
- PMID 24370833
- Global reaction route mapping of isomerization pathways of exotic C6H molecular species.
- Vikas, Kaur G.Author information Quantum Chemistry Group, Department of Chemistry and Centre of Advanced Studies in Chemistry, Panjab University, Chandigarh 160 014, India.AbstractC6H radical is known to exist in the astrophysical environment in linear form; however, it may originate from nonlinear isomeric forms. Potential energy surface of C6H is explored to search isomers of C6H and transition states connecting them. This work reports first-ever identification of reaction pathways for isomerization of C6H. The reaction route search is performed through global reaction route mapping method, which utilizes an uphill walking technique based on an anharmonic downward distortion following approach to search intermediates and transition states. The computations performed at the CASSCF∕aug-cc-pVTZ, CCSD(T)∕6-311++G(d,p)∕∕DFT∕B3LYP∕6-311++G(d,p), and DFT∕B3LYP∕aug-cc-pVTZ levels of the theory identified 14 isomers (including 8 new isomeric forms of C6H) and 28 transition states. Most of the identified isomers are found to have significant multireference character. The kinetic stability and natural bond orbital analysis of the identified isomers is also investigated. The isomeric forms are further characterized using spectral analysis involving rotational constants, vibrational frequencies, and Raman scattering activities as well as analyzing the effect of isotopic substitution of hydrogen on the spectral features. This study proposes that the linear-C6H can readily isomerize to a six-member ring isomer.
- The Journal of chemical physics.J Chem Phys.2013 Dec 14;139(22):224311. doi: 10.1063/1.4840755.
- C6H radical is known to exist in the astrophysical environment in linear form; however, it may originate from nonlinear isomeric forms. Potential energy surface of C6H is explored to search isomers of C6H and transition states connecting them. This work reports first-ever identification of reaction
- PMID 24341596
Japanese Journal
- ポスター講演 送信電力制御を用いたMU-MIMO-OFDM非線形ひずみ抑圧法に関する検討 (ワイドバンドシステム)
- 長田 弦,竹渕 翔矢,前原 文明
- 電子情報通信学会技術研究報告 : 信学技報 112(317), 33-38, 2012-11-26
- NAID 40019522818
- A Study on OFDM Clipping and Filtering Method Employing SNDR-Based Transmit Power Control (ワイドバンドシステム)
- 竹渕 翔矢,長田 弦,前原 文明
- 電子情報通信学会技術研究報告 : 信学技報 112(264), 1-6, 2012-10-26
- NAID 40019482546
Related Links
- Nonlinear distortion is a term used (in fields such as electronics, audio and telecommunications) to describe the phenomenon of a non-linear relationship between the "input" and "output" signals of - for example - an electronic device.
★リンクテーブル★
[★]
- ゆがめること、ゆがみ、ねじれ
- ゆがめられた状態、ゆがんだもの。(身体・骨格などの)弯曲、ひずみ。捻挫
- (事実などの)歪曲、曲解
- (精神分析)歪曲
[★]
- 関
- non-linear、nonlinearity