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Autore: Grafiati

Pubblicato: 4 giugno 2021

Ultima modifica: 25 gennaio 2023

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1

AURICH, R., e J. BOLTE. "QUANTIZATION RULES FOR STRONGLY CHAOTIC SYSTEMS". Modern Physics Letters B 06, n. 27 (20 novembre 1992): 1691–719. http://dx.doi.org/10.1142/s0217984992001393.

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We discuss the quantization of strongly chaotic systems and apply several quantization rules to a model system given by the unconstrained motion of a particle on a compact surface of constant negative Gaussian curvature. We study the periodic-orbit theory for distinct symmetry classes corresponding to a parity operation which is always present when such a surface has genus two. Recently, several quantization rules based on periodic orbit theory have been introduced. We compare quantizations using the dynamical zeta function Z(s) with the quantization condition [Formula: see text] where a periodic-orbit expression for the spectral staircase N(E) is used. A general discussion of the efficiency of periodic-orbit quantization then allows us to compare the different methods. The system dependence of the efficiency, which is determined by the topological entropy τ and the mean level density [Formula: see text], is emphasized.

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2

Kivelson, S., e S. A. Trugman. "Quantization of the Hall conductance from density quantization alone". Physical Review B 33, n. 6 (15 marzo 1986): 3629–35. http://dx.doi.org/10.1103/physrevb.33.3629.

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3

Hulle, Marc M. Van, e Dominique Martinez. "On an Unsupervised Learning Rule for Scalar Quantization following the Maximum Entropy Principle". Neural Computation 5, n. 6 (novembre 1993): 939–53. http://dx.doi.org/10.1162/neco.1993.5.6.939.

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A novel unsupervised learning rule, called Boundary Adaptation Rule (BAR), is introduced for scalar quantization. It is shown that the rule maximizes information-theoretic entropy and thus yields equiprobable quantizations of univariate probability density functions. It is shown by simulations that BAR outperforms other unsupervised competitive learning rules in generating equiprobable quantizations. It is also shown that our rule can do better or worse than the Lloyd I algorithm in minimizing average mean square error, depending on the input distribution. Finally, an application to adaptive non-uniform analog to digital (A/D) conversion is considered.

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4

Kwiat, Doron. "Gravitation, Density, Black Holes and Spatial Quantization". Journal of High Energy Physics, Gravitation and Cosmology 08, n. 04 (2022): 990–1011. http://dx.doi.org/10.4236/jhepgc.2022.84070.

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5

Lafferty, John D. "The density manifold and configuration space quantization". Transactions of the American Mathematical Society 305, n. 2 (1 febbraio 1988): 699. http://dx.doi.org/10.1090/s0002-9947-1988-0924776-9.

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6

Weissbach, S., F. Wyrowski e O. Bryngdahl. "Quantization noise in pulse density modulated holograms". Optics Communications 67, n. 3 (luglio 1988): 167–71. http://dx.doi.org/10.1016/0030-4018(88)90373-2.

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7

Aleksić, Danijela, e Zoran Perić. "ONE-BIT QUANTIZER PARAMETRIZATION FOR ARBITRARY LAPLACIAN SOURCES". Facta Universitatis, Series: Automatic Control and Robotics 1, n. 1 (14 luglio 2022): 035. http://dx.doi.org/10.22190/fuacr220321004a.

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In this paper we suggest an exact formula for the total distortion of one-bit quantizer and for the arbitrary Laplacian probability density function (pdf). Suggested formula additionally extends normalized case of zero mean and unit variance, which is the most applied quantization case not only in traditional quantization rather in contemporary solutions that involve quantization. Additionally symmetrical quantizer’s representation levels are calculated from minimal distortion criteria. Note that one-bit quantization is the most sensitive quantization from the standpoint of accuracy degradation and quantization error, thus increasing importance of the suggested parameterization of one-bit quantizer.

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8

GAITE, J. "ANGULAR QUANTIZATION AND THE DENSITY MATRIX RENORMALIZATION GROUP". Modern Physics Letters A 16, n. 17 (7 giugno 2001): 1109–16. http://dx.doi.org/10.1142/s0217732301004364.

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Path integral techniques for the density matrix of a one-dimensional statistical system near a boundary previously employed in black-hole physics are applied to provide a new interpretation of the density matrix renormalization group: Its efficacy is due to the concentration of quantum states near the boundary.

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9

Seo, Sanghyun, e Juntae Kim. "Efficient Weights Quantization of Convolutional Neural Networks Using Kernel Density Estimation based Non-uniform Quantizer". Applied Sciences 9, n. 12 (23 giugno 2019): 2559. http://dx.doi.org/10.3390/app9122559.

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Convolutional neural networks (CNN) have achieved excellent results in the field of image recognition that classifies objects in images. A typical CNN consists of a deep architecture that uses a large number of weights and layers to achieve high performance. CNN requires relatively large memory space and computational costs, which not only increase the time to train the model but also limit the real-time application of the trained model. For this reason, various neural network compression methodologies have been studied to efficiently use CNN in small embedded hardware such as mobile and edge devices. In this paper, we propose a kernel density estimation based non-uniform quantization methodology that can perform compression efficiently. The proposed method performs efficient weights quantization using a significantly smaller number of sampled weights than the number of original weights. Four-bit quantization experiments on the classification of the ImageNet dataset with various CNN architectures show that the proposed methodology can perform weights quantization efficiently in terms of computational costs without significant reduction in model performance.

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10

Tadic, Predrag, Zeljko Djurovic e Branko Kovacevic. "Analysis of speech waveform quantization methods". Journal of Automatic Control 18, n. 1 (2008): 19–22. http://dx.doi.org/10.2298/jac0801019t.

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Digitalization, consisting of sampling and quantization, is the first step in any digital signal processing algorithm. In most cases, the quantization is uniform. However, having knowledge of certain stochastic attributes of the signal (namely, the probability density function, or pdf), quantization can be made more efficient, in the sense of achieving a greater signal to quantization noise ratio. This means that narrower channel bandwidths are required for transmitting a signal of the same quality. Alternatively, if signal storage is of interest, rather than transmission, considerable savings in memory space can be made. This paper presents several available methods for speech signal pdf estimation, and quantizer optimization in the sense of minimizing the quantization error power.

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11

Wang, Shuo, Mei Yu, Hangfei Wang e Wen Tan. "Switched Quantization Level Control of Networked Control Systems with Packet Dropouts". Mathematical Problems in Engineering 2014 (2014): 1–8. http://dx.doi.org/10.1155/2014/890543.

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This paper investigates the relationship between the maximum allowable dropout bound and the quantization density. Networked Control System (NCS) is described as a time-delay switched system with constrained switching signals. A switched dynamic output feedback controller with prescribed disturbance attenuation level is designed via a cone complement linearization approach. A novel stability criterion is obtained by switched system theory. Furthermore, finding an appropriate quantization density used when packet dropout occurs is converted to an optimization problem.

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12

McFadden, S. M., e K. Swanston. "Mapping of Amplitude onto CRT Luminance in Frequency-Time-Intensity Displays". Proceedings of the Human Factors Society Annual Meeting 30, n. 2 (settembre 1986): 164–67. http://dx.doi.org/10.1177/154193128603000213.

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A common method of presenting passive sonar information on a CRT is the frequency–time–intensity (FTI) display. Detection of targets on an FTI display can be affected by the method used to map the original sonar input onto the visual display. The current study examined the problem of mapping the acoustic amplitude of the incoming sound onto CRT luminance. Detectability of a single target line was measured as a function of the number of quantization levels used to map amplitude onto CRT luminance (2, 4, 8, 16 or 256) and the marking density (percentage of the display set to other than background luminance). Marking density was varied by mapping all amplitude values below a fixed cut-off point (either 3, 1, or 0 S.D. below the mean of the noise) on to the lowest quantization level. On average, detection performance improved more than 3 dB as the number of quantization levels increased from two to eight. If amplitude was mapped onto fewer than sixteen quantization levels, the selection of a cut–off point was important.

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13

Hu, YaoZhong. "Stochastic quantization and ergodic theorem for density of diffusions". Science China Mathematics 55, n. 11 (novembre 2012): 2285–96. http://dx.doi.org/10.1007/s11425-012-4523-7.

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14

Marongwe, Stuart. "A Covariant Canonical Quantization of General Relativity". Advances in High Energy Physics 2018 (19 dicembre 2018): 1–7. http://dx.doi.org/10.1155/2018/4537058.

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A Hamiltonian formulation of General Relativity within the context of the Nexus Paradigm of quantum gravity is presented. We show that the Ricci flow in a compact matter free manifold serves as the Hamiltonian density of the vacuum as well as a time evolution operator for the vacuum energy density. The metric tensor of GR is expressed in terms of the Bloch energy eigenstate functions of the quantum vacuum allowing an interpretation of GR in terms of the fundamental concepts of quantum mechanics.

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15

FAN, HONG-YI, e SHUAI WANG. "MUTUAL TRANSFORMATION BETWEEN DIFFERENT s-PARAMETRIZED QUANTIZATION SCHEMES BASED ON s-ORDERED WIGNER OPERATOR". Modern Physics Letters A 27, n. 16 (24 maggio 2012): 1250089. http://dx.doi.org/10.1142/s0217732312500897.

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s-parametrized quantization is essential to phase space theory of quantum mechanical. Based on s-ordered Wigner operator, we examine the classical correspondence of the s2-parametrized Wigner operator through the s1-parametrized quantization scheme, and establish the mutual transformation relation between different s-parametrized quantization schemes. It turns out that the s-parametrized Wigner operator's s-ordering is just the Dirac delta function, which seems to be a new result. As applications, we derive the s-ordered form of the density operator of thermal states and some new generating function formula of Hermite polynomials.

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16

Pham The, Song, Theu Luong Thi e Thu Nguyen Van. "EPLETION DENSITY OF IDEAL GAS BOSE-EINSTEIN CONDENSATE BY TWO PARALLEL PLATES". Journal of Science Natural Science 65, n. 6 (giugno 2020): 82–89. http://dx.doi.org/10.18173/2354-1059.2020-0032.

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By means of the second quantization formalism, the condensate density of an infinite Bose gas and finite Bose gas is studied in the broken phase. Our results show that the compactification in one-direction makes the remarkable changes in the condensate density.

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17

OHKUWA, YOSHIAKI. "THIRD QUANTIZATION OF KALUZA–KLEIN COSMOLOGY AND COMPACTIFICATION". International Journal of Modern Physics A 13, n. 23 (20 settembre 1998): 4091–100. http://dx.doi.org/10.1142/s0217751x98001918.

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We study on the third quantization of a Kaluza–Klein toy model. In this model time (x) is defined by the scale factor of universe, and the space coordinate (y) is defined by the ratio of the scales of the ordinary space and the internal space. We calculate the number density of the universes created from nothing and examine whether the compactification can be explained statistically by the idea of the third quantization.

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18

Li Ping e W. K. Leung. "Decoding low density parity check codes with finite quantization bits". IEEE Communications Letters 4, n. 2 (febbraio 2000): 62–64. http://dx.doi.org/10.1109/4234.824757.

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19

Ritter, H. "Asymptotic level density for a class of vector quantization processes". IEEE Transactions on Neural Networks 2, n. 1 (1991): 173–75. http://dx.doi.org/10.1109/72.80310.

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20

Qin, Zhengda, Badong Chen, Yuantao Gu, Nanning Zheng e Jose C. Principe. "Probability Density Rank-Based Quantization for Convex Universal Learning Machines". IEEE Transactions on Neural Networks and Learning Systems 31, n. 8 (agosto 2020): 3100–3113. http://dx.doi.org/10.1109/tnnls.2019.2935502.

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21

Ioannidou, T., e N. S. Manton. "The energy of scattering solitons in the Ward model". Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences 461, n. 2059 (24 maggio 2005): 1965–73. http://dx.doi.org/10.1098/rspa.2005.1451.

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The energy density of a scattering soliton solution in Ward's integrable chiral model is shown to be instantaneously the same as the energy density of a static multi-lump solution of the sigma model. This explains the quantization of the total energy in the Ward model.

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22

KRUGLOV, S. I. "QUANTIZATION OF BOSONIC FIELDS WITH TWO MASS AND SPIN STATES". Modern Physics Letters A 23, n. 26 (30 agosto 2008): 2141–47. http://dx.doi.org/10.1142/s0217732308027370.

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We investigate bosonic fields possessing two mass and spin states. The density matrix in the first-order formalism is obtained. The quantization of fields in the first-order formulation is performed and propagators are found.

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23

Yakimov, Vladimir. "Periodogram estimating the spectral power density based upon signals’ binary-sign stochastic quantization using window functions". Informatics and Automation 20, n. 2 (30 marzo 2021): 341–70. http://dx.doi.org/10.15622/ia.2021.20.2.4.

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Spectral analysis of signals is used as one of the main methods for studying systems and objects of various physical natures. Under conditions of a priori statistical uncertainty, the signals are subject to random changes and noise. Spectral analysis of such signals involves the estimation of the power spectral density (PSD). One of the classical methods for estimating PSD is the periodogram method. The algorithms that implement this method in digital form are based on the discrete Fourier transform. Digital multiplication operations are mass operations in these algorithms. The use of window functions leads to an increase in the number of these operations. Multiplication operations are among the most time consuming operations. They are the dominant factor in determining the computational capabilities of an algorithm and determine its multiplicative complexity. The paper deals with the problem of reducing the multiplicative complexity of calculating the periodogram estimate of the PSD using window functions. The problem is solved based on the use of binary-sign stochastic quantization for converting a signal into digital form. This two-level signal quantization is carried out without systematic error. Based on the theory of discrete-event modeling, the result of a binary-sign stochastic quantization in time is considered as a chronological sequence of significant events determined by the change in its values. The use of a discrete-event model for the result of binary-sign stochastic quantization provided an analytical calculation of integration operations during the transition from the analog form of the periodogram estimation of the SPM to the mathematical procedures for calculating it in discrete form. These procedures became the basis for the development of a digital algorithm. The main computational operations of the algorithm are addition and subtraction arithmetic operations. Reducing the number of multiplication operations decreases the overall computational complexity of the PSD estimation. Numerical experiments were carried out to study the algorithm operation. They were carried out on the basis of simulation modeling of the discrete-event procedure of binary-sign stochastic quantization. The results of calculating the PSD estimates are presented using a number of the most famous window functions as an example. The results obtained indicate that the use of the developed algorithm allows calculating periodogram estimates of PSD with high accuracy and frequency resolution in the presence of additive white noise at a low signal-to-noise ratio. The practical implementation of the algorithm is carried out in the form of a functionally independent software module. This module can be used as a part of complex metrologically significant software for operational analysis of the frequency composition of complex signals.

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24

Zhang, Yaoli, e Jun Zhao. "Output regulation for switched discrete-time systems with output signal quantization". Transactions of the Institute of Measurement and Control 43, n. 9 (11 febbraio 2021): 2094–102. http://dx.doi.org/10.1177/0142331221989887.

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This paper investigates the output regulation problem for switched discrete-time systems with output quantization. We adopt the quantized output in feedback controllers and allow each subsystem to have its own quantization density, so that the communication network can be efficiently utilized. By using the different coordinates transformation, the solvability of the output regulation problem is guaranteed under deigned output feedback controllers with the switching signals satisfying a dwell time constraint. In the simulation, a pulse-width modulation driven boost converter model is employed to validate the result.

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25

Meis, Constantin. "Vector Potential Quantization and the Quantum Vacuum". Physics Research International 2014 (19 giugno 2014): 1–5. http://dx.doi.org/10.1155/2014/187432.

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We investigate the quantization of the vector potential amplitude of the electromagnetic field to a single photon state starting from the fundamental link equations between the classical electromagnetic theory and the quantum mechanical expressions. The resulting wave-particle formalism ensures a coherent transition between the classical electromagnetic wave theory and the quantum representation. A quantization constant of the photon vector potential is defined. A new quantum vacuum description results directly in having very low energy density. The calculated spontaneous emission rate and Lambs shift for the nS states of the hydrogen atom are in agreement with quantum electrodynamics. This low energy quantum vacuum state might be compatible with recent astrophysical observations.

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26

Carbone, P., e D. Petri. "Marginal probability density function of granular quantization error in uniform quantizers". IEEE Transactions on Information Theory 47, n. 3 (marzo 2001): 1237–42. http://dx.doi.org/10.1109/18.915696.

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GRAF, SIEGFRIED, e HARALD LUSCHGY. "The point density measure in the quantization of self-similar probabilities". Mathematical Proceedings of the Cambridge Philosophical Society 138, n. 3 (maggio 2005): 513–31. http://dx.doi.org/10.1017/s030500410500842x.

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28

Kellendonk, J. "Topological quantization of boundary forces and the integrated density of states". Journal of Physics A: Mathematical and General 37, n. 15 (29 marzo 2004): L161—L166. http://dx.doi.org/10.1088/0305-4470/37/15/l02.

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29

Kong, Weihao, e Wu-Jun Li. "Double-Bit Quantization for Hashing". Proceedings of the AAAI Conference on Artificial Intelligence 26, n. 1 (20 settembre 2021): 634–40. http://dx.doi.org/10.1609/aaai.v26i1.8208.

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Hashing, which tries to learn similarity-preserving binary codes for data representation, has been widely used for efficient nearest neighbor search in massive databases due to its fast query speed and low storage cost. Because it is NP hard to directly compute the best binary codes for a given data set, mainstream hashing methods typically adopt a two-stage strategy. In the first stage, several projected dimensions of real values are generated. Then in the second stage, the real values will be quantized into binary codes by thresholding. Currently, most existing methods use one single bit to quantize each projected dimension. One problem with this single-bit quantization (SBQ) is that the threshold typically lies in the region of the highest point density and consequently a lot of neighboring points close to the threshold will be hashed to totally different bits, which is unexpected according to the principle of hashing. In this paper, we propose a novel quantization strategy, called double-bit quantization (DBQ), to solve the problem of SBQ. The basic idea of DBQ is to quantize each projected dimension into double bits with adaptively learned thresholds. Extensive experiments on two real data sets show that our DBQ strategy can significantly outperform traditional SBQ strategy for hashing.

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Shih, Wei-Kai, Srinivas Jallepalli, Mahbub Rashed, Christine M. Maziar e Al F. Tasch Jr. "Study of Electron Velocity Overshoot in NMOS Inversion Layers". VLSI Design 8, n. 1-4 (1 gennaio 1998): 429–35. http://dx.doi.org/10.1155/1998/65364.

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Non-local electron transport in nMOSFET inversion layers has been studied by Monte Carlo (MC) simulations. Inversion layer quantization has been explicitly included in the calculation of density of states and scattering rate for low-energy electrons while bulk band structure is used to describe the transport of more energetic electrons. For uniform, high-lateral field conditions, the effects of quantization are less pronounced due to the depopulation of electrons in the lower-lying subbands. On the other hand, Monte Carlo results for carrier transport in spatially varying lateral fields (such as those in the inversion layer of MOSFETs) clearly indicate that depopulation of the low-lying subbands is less evident in the non-local transport regime. Quasi-2D simulations have shown that, at high transverse effective field, the inclusion of a quantization domain does have an impact on the calculated spatial velocity transient.

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Kryukov, S., e M. A. Walton. "Star-quantization of an infinite wall". Canadian Journal of Physics 84, n. 6-7 (15 gennaio 2006): 557–63. http://dx.doi.org/10.1139/p06-017.

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In deformation quantization (a.k.a. the WignerWeylMoyal formulation of quantum mechanics), we consider a single quantum particle moving freely in one dimension, except for the presence of one infinite potential wall. Dias and Prata pointed out that, surprisingly, its stationary-state Wigner function does not obey the naive equation of motion, i.e., the naive stargenvalue (*-genvalue) equation. We review our recent work on this problem that treats the infinite wall as the limit of a Liouville potential. Also included are some new results: (i) we show explicitly that the Wigner-Weyl transform of the usual density matrix is the physical solution, (ii) we prove that an effective-mass treatment of the problem is equivalent to the Liouville one, and (iii) we point out that self-adjointness of the operator Hamiltonian requires a boundary potential, but one apparently different from that proposed by Dias and Prata. PACS Nos.: 03.65.w, 03.65.Ca, 03.65.Ge

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Maki, K., B. Dora, B. Korin-Hamzic, M. Basletic, A. Virosztek e M. V. Kartsovnik. "Brave new world of unconventional density waves". Journal de Physique IV 12, n. 9 (novembre 2002): 49–52. http://dx.doi.org/10.1051/jp4:20020352.

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Recently many people discuss unconventional density wave (i.e. UCDW and USDW). Unlike in conventional density waves, the quasiparticle excitations in these systems are gapless. The appearence of these systems suggests paradigm shift from quasi ID system to quasi 2D and 3D systems. Here we limit ourselves to the angular dependent magnetoresistance (ADMR) observed in the low temperature phase (LTP) of α-(BEDT-TTF)2KHg(SCN)4. Here we show that UCDW describes successfully many features of ADMR as manifestation of the Landau quantization of the quasiparticle spectrum in magnetic field. Indeed ADMR will provide a unique window to access UDW like the AF phase in URu2Si2, the pseudogap phase in high Tc cuprates and the glassy phase in organic superconductor κ-(ET)2 salts.

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Caglioti, Emanuele, François Golse e Mikaela Iacobelli. "A gradient flow approach to quantization of measures". Mathematical Models and Methods in Applied Sciences 25, n. 10 (22 giugno 2015): 1845–85. http://dx.doi.org/10.1142/s0218202515500475.

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In this paper we study a gradient flow approach to the problem of quantization of measures in space dimension one. By embedding our problem in L2, we find a continuous version of this problem corresponding to the limit as the number of atoms in the approximating measure tends to infinity. Under some suitable regularity assumptions on the density, we prove uniform stability and quantitative convergence results for the discrete and continuous dynamics.

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DÓRA, BALÁZS, KAZUMI MAKI e ATTILA VIROSZTEK. "RECENT ADVANCES IN UNCONVENTIONAL DENSITY WAVES". Modern Physics Letters B 18, n. 09 (10 aprile 2004): 327–44. http://dx.doi.org/10.1142/s0217984904006925.

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The unconventional density wave (UDW) was speculated on as a possible electronic ground state in the excitonic insulator in 1968. The recent surge of interest in UDW's is partly due to the proposal that the pseudogap phase in high Tc cuprate superconductors is a d-wave density wave (d-DW). Here we review our recent works on UDW's within the framework of mean field theory. In particular, we have shown that many properties of the low temperature phase (LTP) in α-( BEDT-TTF )2 MHg ( SCN )4, with M = K , Rb and Tl , are well characterized in terms of the unconventional charge density wave (UCDW). In this identification the Landau quantization of the quasiparticle motion in a magnetic field (the Nersesyan effect) plays the crucial role. Indeed, the angle-dependent magnetoresistance and the negative giant Nernst effect are two hallmarks of UDW's.

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Ulhoa, Sérgio, Ednardo Spaniol e Ronni Amorim. "On Quantization of a Slowly Rotating Kerr Black Hole in Teleparallel Gravity". Universe 5, n. 1 (16 gennaio 2019): 29. http://dx.doi.org/10.3390/universe5010029.

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In this article we calculate the total angular momentum for Kerr space-time for slow rotations in the context of teleparallel gravity. In order to analyze the role of such a quantity, we apply Weyl quantization method to obtain a quantum equation for the z-component of the angular momentum density, and for the squared angular momentum density as well. We present an approximate solution using the Adomian decomposition method (AM), which reveals a discrete characteristic for angular momentum.

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Huang, Kewang, Jianfeng Wang e Feng Pan. "Nonfragile Quantized Dissipative Filter for Nonlinear Networked Systems". Mathematical Problems in Engineering 2019 (3 marzo 2019): 1–14. http://dx.doi.org/10.1155/2019/5659873.

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To address the problem of filter parameter perturbation in nonlinear networked systems, a nonfragile quantized dissipative filter is designed by considering the coexistence of random one-step time delay, multipacket losses, and quantization error. We acquired the sufficient conditions for the existence of filter by choosing appropriate Lyapunov function as well as utilizing linear matrix inequality. Furthermore, we obtained the parameter expressions of the designed filter. The designed filter could meet the performance requirements of stability and dissipativity for the filter error system under the condition of allowed time delays, packet loss probability, and quantization density. The effectiveness of the designed filter is verified by numerical simulation.

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Dikshit, Biswaranjan. "A new cosmological model based on quantization of the zero-point field". Canadian Journal of Physics 100, n. 4 (aprile 2022): 218–25. http://dx.doi.org/10.1139/cjp-2021-0278.

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Inflation has presented solutions for a number of important cosmological problems while leaving some unanswered. In this paper, we present a new cosmological model based on the quantization of the zero-point field, which is consistent with empirical data, requires fewer assumptions, and presents answers to some of those unanswered questions. A comparison between standard cosmology and the theory presented in this paper is given herein. Vacuum energy density: The standard inflationary model needs both Hubble’s constant and matter density to estimate the vacuum energy density, but new cosmological model needs only Hubble’s constant. Non-vacuum energy density: The standard model cannot predict the non-vacuum energy density, but the new model can predict it using only Hubble’s constant. Ratio of vacuum energy to total energy: The standard model cannot predict the ratio of vacuum energy to total energy, but the new model can predict it, without using Hubble’s constant. Energy conservation: In the standard model, total energy is not conserved before inflation and at the time of the creation of the universe, but in the new model total energy is mathematically proved to be conserved from the beginning of the universe as net energy (including gravitational potential energy) is always zero. Flatness and homogeneity: The standard model requires an inflaton field with a specific potential energy distribution to explain it, but the new model does not need any such hypothetical field; the zero-point field is sufficient.

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Bhaduri, R. K., D. W. L. Sprung e A. Suzuki. "When is the lowest order WKB quantization exact?" Canadian Journal of Physics 84, n. 6-7 (15 gennaio 2006): 573–81. http://dx.doi.org/10.1139/p06-024.

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First, two conditions are specified for the lowest order Wentzel–Kramers–Brillouin quantization rule to yield exact results. These rules are related to the periodic orbit decomposition of the quantum density of states. This approach is then applied to supersymmetric quantum mechanics. It leads to a new derivation of the result that shape-invariant potentials give exact results when the classical action is calculated with the square of the super potential, but without the Maslov index or the Langer correction.PACS Nos.: 03.65.Sq, 12.60.Jv

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Mena-Parra, J., K. Bandura, M. A. Dobbs, J. R. Shaw e S. Siegel. "Quantization Bias for Digital Correlators". Journal of Astronomical Instrumentation 07, n. 02n03 (settembre 2018): 1850008. http://dx.doi.org/10.1142/s2251171718500083.

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In radio interferometry, the quantization process introduces a bias in the magnitude and phase of the measured correlations which translates into errors in the measurement of source brightness and position in the sky, affecting both the system calibration and image reconstruction. In this paper, we investigate the biasing effect of quantization in the measured correlation between complex-valued inputs with a circularly symmetric Gaussian probability density function (PDF), which is the typical case for radio astronomy applications. We start by calculating the correlation between the input and quantization error and its effect on the quantized variance, first in the case of a real-valued quantizer with a zero mean Gaussian input and then in the case of a complex-valued quantizer with a circularly symmetric Gaussian input. We demonstrate that this input-error correlation is always negative for a quantizer with an odd number of levels, while for an even number of levels, this correlation is positive in the low signal level regime. In both cases, there is an optimal interval for the input signal level for which this input-error correlation is very weak and the model of additive uncorrelated quantization noise provides a very accurate approximation. We determine the conditions under which the magnitude and phase of the measured correlation have negligible bias with respect to the unquantized values: we demonstrate that the magnitude bias is negligible only if both unquantized inputs are optimally quantized (i.e. when the uncorrelated quantization error model is valid), while the phase bias is negligible when (1) at least one of the inputs is optimally quantized, or when (2) the correlation coefficient between the unquantized inputs is small. Finally, we determine the implications of these results for radio interferometry.

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40

Dupuis, N., e K. Sengupta. "Field-induced spin-density-wave phases in TMTSF organic conductors: Quantizationversusnon-quantization". Journal de Physique IV (Proceedings) 114 (aprile 2004): 61–65. http://dx.doi.org/10.1051/jp4:2004114011.

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41

Ning, Zepeng, Lixian Zhang, Jose de Jesus Rubio e Xunyuan Yin. "Asynchronous Filtering for Discrete-Time Fuzzy Affine Systems With Variable Quantization Density". IEEE Transactions on Cybernetics 47, n. 1 (gennaio 2017): 153–64. http://dx.doi.org/10.1109/tcyb.2015.2509170.

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42

Shu-Yan, Ao, Cheng Tai-Wang, Li Xiao-Feng, Wu Ling-An e Fu Pan-Ming. "Energy Quantization and Probability Density of Electron in Intense-Field-Atom Interactions". Chinese Physics Letters 20, n. 9 (29 agosto 2003): 1482–84. http://dx.doi.org/10.1088/0256-307x/20/9/320.

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43

Sojasi, A., M. Mohsenzadeh e R. Saffari. "Large-Scale Effect of Krein Quantization Method on the Matter Density Perturbations". International Journal of Theoretical Physics 54, n. 10 (8 marzo 2015): 3454–61. http://dx.doi.org/10.1007/s10773-015-2586-2.

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44

Berra-Montiel, Jasel, e Alberto Molgado. "Coherent representation of fields and deformation quantization". International Journal of Geometric Methods in Modern Physics 17, n. 11 (26 agosto 2020): 2050166. http://dx.doi.org/10.1142/s0219887820501662.

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Motivated by some well-known results in the phase space description of quantum optics and quantum information theory, we aim to describe the formalism of quantum field theory by explicitly considering the holomorphic representation for a scalar field within the deformation quantization program. Notably, the symbol of a symmetric ordered operator in terms of holomorphic variables may be straightforwardly obtained by the quantum field analogue of the Husimi distribution associated with a normal ordered operator. This relation also allows to establish a [Formula: see text]-equivalence between the Moyal and the normal star-products. In addition, by writing the density operator in terms of coherent states we are able to directly introduce a series representation of the Wigner functional distribution, which may be convenient in order to calculate probability distributions of quantum field observables without performing formal phase space integrals at all.

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45

Chaudhry, Amit, e Nath Roy. "A comparative study of hole and electron inversion layer quantization in MOS structures". Serbian Journal of Electrical Engineering 7, n. 2 (2010): 185–93. http://dx.doi.org/10.2298/sjee1002185c.

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In this paper, an analytical model has been developed to study inversion layer quantization in nanoscale Metal Oxide Semiconductor Field Effect Oxide p-(MOSFET). n-MOSFETs have been studied using the variation approach and the p-MOSFETs have been studied using the triangular well approach. The inversion charge density and gate capacitance analysis for both types of transistors has been done. There is a marked decrease in the inversion charge density and the capacitance of the p-MOSFET as compared to n-MOSFETs. The results are compared with the numerical results showing good agreement.

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Nikolic, Jelena, e Zoran Peric. "Two approaches to design of forward adaptive piecewise uniform scalar quantizers". Facta universitatis - series: Electronics and Energetics 26, n. 1 (2013): 61–68. http://dx.doi.org/10.2298/fuee1301061n.

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In this paper, two forward adaptive piecewise uniform scalar quantizers are proposed for high-quality quantization of speech signals modeled by the Laplacian probability density function. In designing both forward adaptive piecewise uniform scalar quantizers an equidistant support region partition is assumed and a distribution of the number of reproduction levels per segments is optimized. The proposed models differ in the approach of determining the reproduction levels. In particular, one model defines the reproduction levels as the cell centroids and the other one as the cell midpoints. We show that, in the high-resolution case, the proposed quantizers provide approximately the same performance being close to the one of the forward adaptive nonlinear scalar compandor with equal number of quantization levels.

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47

ARRIOLA, E. RUIZ, e L. L. SALCEDO. "SEMICLASSICAL EXPANSION FOR DIRAC HAMILTONIANS". Modern Physics Letters A 08, n. 22 (20 luglio 1993): 2061–69. http://dx.doi.org/10.1142/s021773239300177x.

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A simple and efficient calculation of the level density of Dirac Hamiltonians in the semi-classical approximation is presented. The method is applied to compute the level density up to ħ4-order of a Dirac Hamiltonian with time independent scalar and electromagnetic external fields. The final expressions are explicitly gauge invariant and convergent at the turning points. As a byproduct, we obtain ħ-corrections to the semiclassical quantization rule of a Dirac Hamiltonian in D space dimensions. The result is illustrated in an exactly solvable problem.

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Guan, Wu, e Li Ping Liang. "Lossy Source Compression Using Belief Propagation with Decimation over Multi-Edge Type Factor Graphs of LDGM Codes". Applied Mechanics and Materials 610 (agosto 2014): 437–42. http://dx.doi.org/10.4028/www.scientific.net/amm.610.437.

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A low complexity approach for binary quantization is proposed. This approach uses a multi-edge type bipartite graph of the low density generator matrix (LDGM) code with the belief propagation algorithm to encode the informations. A damping decimation is developed for the algorithm convergence. Simulation results show that our algorithm achieves near Shannon capacity performance with reduced complexity.

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49

BRACKEN, PAUL. "CONSTRAINT STRUCTURE AND QUANTIZATION OF A NON-ABELIAN GAUGE THEORY BY MEANS OF DIRAC BRACKETS". Modern Physics Letters A 24, n. 32 (20 ottobre 2009): 2611–21. http://dx.doi.org/10.1142/s0217732309031818.

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An SO(3) non-Abelian gauge theory is introduced. The Hamiltonian density is determined and the constraint structure of the model is derived. The first-class constraints are obtained and gauge-fixing constraints are introduced into the model. Finally, using the constraints, the Dirac brackets can be determined and a canonical quantization is found using Dirac's procedure.

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50

Golikov, D. S. "Maslov symbol for the density matrix in the case of quantization of pairs". Moscow University Physics Bulletin 65, n. 6 (dicembre 2010): 466–70. http://dx.doi.org/10.3103/s002713491006007x.

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