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141.
We give necessary and sufficient conditions on the wavelet coefficients of a function for being a member of some BMOφ (w) space. We achieve this characterization for a wide variety of wavelet systems. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
142.
Yi-Bin Huang Song-Song Li Yi-You Nie 《International Journal of Theoretical Physics》2008,47(11):2819-2823
We investigate the scheme which enables encoding of n qudits whose Hilbert spaces are of different dimensions to one qudit of dimension smaller than that of the Hilbert space
of the n qudits and then probabilistically but error-free decoding any subset of k qudits. We also give a formula for calculating the average probability of successful decoding. 相似文献
144.
In this paper, a method of meshwork multipicture holography is suggested, which uses spatially coded recording plate with one dimension grating meshwork. The method is simple in coding and easy to realize. The reconstructing images obtained are very clear. 相似文献
145.
This article reports the design and implementation of a graphical display that presents an approximation to vocal tract area in real time for voiced vowel articulation. The acoustic signal is digitally sampled by the system. From these data a set of reflection coefficients is derived using linear predictive coding. A matrix of area coefficients is then determined that approximates the vocal tract area of the user. From this information a graphical display is then generated. The complete cycle of analysis and display is repeated at ≈20 times/s. Synchronised audio and visual sequences can be recorded and used as dynamic targets for articulatory development. Use of the system is illustrated by diagrams of system output for spoken cardinal vowels and for vowels sung in a trained and untrained style 相似文献
146.
K. J. Falconer 《Journal of statistical physics》1992,67(3-4):781-793
We highlight a correspondence between order-two densities and wavelet-like transforms of certain fractal measures. We use a variant of the ergodic theorem to demonstrate that these densities and transforms are well-behaved for a large class of quasi-self-similar fractals. We show that parallel ideas can be used to study the local behavior of certain fractal functions. 相似文献
147.
For the Gaussian channel Y(t) = Φ(ξ(s), Y(s); s ≦ t) + X(t), the mutual information I(ξ, Y) between the message ξ(·) and the output Y(·) is evaluated, where X(·) is a Gaussian noise. Furthermore, the optimal coding under average power constraints is constructed. 相似文献
148.
Rebbi's multispin coding technique is improved and applied to the kinetic Ising model with size 600*600*600. We give the central part of our computer program (for a CDC Cyber 76), which will be helpful also in a simulation of smaller systems, and describe the other tricks necessary to go to large lattices. The magnetizationM atT=1.4*T
c is found to decay asymptotically as exp(-t/2.90) ift is measured in Monte Carlo steps per spin, and M(t = 0) = 1 initially. 相似文献
149.
This is the first of several papers dealing with the application of statistical thermodynamic methodology to the solution of coding and communication theory problems. Emphasis is placed on the various ensemble techniques of statistical mechanics, the words or samples of a message taking the place of molecules in the prototype physical system. Analogs of temperature, internal energy, pressure, chemical potential, volume, entropy, etc., are developed. The isomorphism with thermodynamics is complete and these quantities transform (for example, by partial differentiation) in exactly the same way as the prototype physical quantities. The methods are nicely applicable to coding cases involving sources with memory, in which case, correlation can be discussed in terms of analog coupling energies between signals or words so that the store of many-body-problem techniques can be used. In addition, the manipulative freedom stemming from the possibility of choosing from a multiplicity of ensembles constrained by intensive parameters proves a distinct advantage. A concrete example dealing with the choice of a compact code for a nonextended source with memory is presented. The compact code is derived, and some discussion is given concerning the breadth of its power spectrum. In a following paper, its autocorrelation function within the framework of pulse code modulation is derived and transformed by Wiener theory so that the power spectrum is directly exhibited (along with the spectra for several other cases).Research supported under AFOSR Grant No. 70-1877. The present work is contribution No. 2643 of the Department of Chemistry, University of California-Los Angeles. 相似文献
150.
Alexandr Křemen 《Journal of statistical physics》1980,23(4):483-494
The biochemical machinery of living systems obeys kinetic laws, but is driven by Gibbs function flows. Both the kinetic and thermodynamic aspects of Gibbs gain, transmission, and utilization are considered. An information-theoretic approach is used to find conditions under which the kinetics encodes the associated Gibbs function flow with the lowest possible error. 相似文献