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41.
Mausumi Pohit 《Optics Communications》2008,281(22):5541-5549
A new perspective of scale-invariant pattern recognition is proposed in this paper. Instead of computing a filter from one of many orthogonal components of the reference object, the scaling factor is estimated from the Fourier spectrums of reference and test images and utilized in rescaling of the spectrum. The test image is correlated with the reference image after rescaling its Fourier spectrum with classical matched filtering. Computer simulation results are presented for a reference object at several scaling versions as well as some non-target objects. 相似文献
42.
Nahmias introduced the concept of a fuzzy variable as a possible axiomatic framework from which a rigorous theory of fuzziness may be constructed. In this paper we attempt to shed more light on fuzzy variables in analogy with random variables. In particular, we study the problem: if X1, X2,…,Xn are mutually unrelated fuzzy variables with common membership function μ and α1, α2,…,αn are real numbers satisfying αi ? o for every i and Σi=1nαi=1, when does does Z = Σi = 1nαiXi have the same membership function μ? 相似文献
43.
E. M. Chance G. M. Clore A. R. Curtis E. P. Shephard 《Journal of computational physics》1981,40(2):318-326
The theory required for the solution of the Hodgkin-Huxley equations for the transmission of the nerve impulse in a moving coordinate system are presented. Using this theory, simulations of the transmission of the nerve impulse over large distances (e.g., 1 m) may be carried out rapidly and accurately. The above theory may be applied to other diffusion problems by appropriate modification to the problem concerned. 相似文献
44.
Montejo M Ureña FP Márquez F González JJ 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2005,62(4-5):1058-1069
The joint experimental and theoretical study of the vibrational spectra of the molecular series (CH3)3SiX (with X=H, F and Br) is carried out. Data from newly recorded IR and Raman spectra for the bromo derivative, experimental data obtained previously for the remaining species, DFT theoretical calculations and the use of the SQMFF procedure have allowed us to propose common patterns and to unify criteria in their assignment. In addition, two sets of averaged scale factors for the B3LYP force field obtained with two different basis sets (6-31G* and DZP+diff) have been proposed for the common bulky moiety of that molecular series. These parameters were used successfully in order to reproduce the frequency of the bands assigned to the (CH3)3Si- group in the vibrational spectra of the corresponding silanolic and methoxy derivatives, i.e., trimethylsilanol and methoxytrimethylsilane, proving their transferability. 相似文献
45.
We examine scale invariant Fulop-Tsutsui couplings in a quantum vertex of a general degree n. We demonstrate that essentially same scattering amplitudes as for the free coupling can be achieved for two (n−1)-parameter Fulop-Tsutsui subfamilies if n is odd, and for three (n−1)-parameter Fulop-Tsutsui subfamilies if n is even. We also work up an approximation scheme for a general Fulop-Tsutsui vertex, using only n δ function potentials. 相似文献
46.
In this paper, we analyze market efficiency for the Shanghai stock market over time using a model-free method known as multifractal detrended fluctuation analysis. Through analyzing the change of scale behavior, we find that the price-limited reform improved the efficiency in the long term, but the influence in the short term was very minor. Employing the method of moving window, using three different measures we find that the Shanghai stock market became more and more efficient after the reform. We also implement the same procedure on volatility series and find the evidence of inefficiency. 相似文献
47.
Enrico Biffis 《Insurance: Mathematics and Economics》2010,46(1):85-3056
We examine discounted penalties at ruin for surplus dynamics driven by a general spectrally negative Lévy process; the natural class of stochastic processes which contains many examples of risk processes which have already been considered in the existing literature. Following from the important contributions of [Zhou, X., 2005. On a classical risk model with a constant dividend barrier. North Am. Act. J. 95-108] we provide an explicit characterization of a generalized version of the Gerber-Shiu function in terms of scale functions, streamlining and extending results available in the literature. 相似文献
48.
Noël Challamel 《Comptes Rendus Mecanique》2018,346(4):320-335
The static and dynamic behaviour of a nonlocal bar of finite length is studied in this paper. The nonlocal integral models considered in this paper are strain-based and relative displacement-based nonlocal models; the latter one is also labelled as a peridynamic model. For infinite media, and for sufficiently smooth displacement fields, both integral nonlocal models can be equivalent, assuming some kernel correspondence rules. For infinite media (or finite media with extended reflection rules), it is also shown that Eringen's differential model can be reformulated into a consistent strain-based integral nonlocal model with exponential kernel, or into a relative displacement-based integral nonlocal model with a modified exponential kernel. A finite bar in uniform tension is considered as a paradigmatic static case. The strain-based nonlocal behaviour of this bar in tension is analyzed for different kernels available in the literature. It is shown that the kernel has to fulfil some normalization and end compatibility conditions in order to preserve the uniform strain field associated with this homogeneous stress state. Such a kernel can be built by combining a local and a nonlocal strain measure with compatible boundary conditions, or by extending the domain outside its finite size while preserving some kinematic compatibility conditions. The same results are shown for the nonlocal peridynamic bar where a homogeneous strain field is also analytically obtained in the elastic bar for consistent compatible kinematic boundary conditions at the vicinity of the end conditions. The results are extended to the vibration of a fixed–fixed finite bar where the natural frequencies are calculated for both the strain-based and the peridynamic models. 相似文献
49.
《Particuology》2018
In this work, a new methodology is introduced to calculate the solids mixing rate in dense gas-fluidized beds using the two-fluid model. The implementation of this methodology into an existing two-fluid model code was carefully verified. The solids phase continuity equation was satisfied using our method, and the sensitivity of the computational results to the time step, computational cell size, and discretization scheme was investigated to determine the optimal simulation settings. Using these simulation settings, the degree of solids mixing was observed to rapidly (exponentially) increase with increasing operating pressure and linearly decrease with increasing bed diameter. Our novel methodology can be applied to analyze mixing processes in large lab-scale beds as an alternative to existing time-consuming simulation techniques such as computational fluid dynamics combined with the discrete element model. 相似文献
50.
消偏光纤陀螺的理论和实验研究 总被引:7,自引:5,他引:2
本文首次在理论上导出消偏型光纤陀螺的零漂和标度因子表达式,并得出以下两个结论:1)在使用约 40 dB偏振器时,导致陀螺漂移的主要因素是强度误差而并不是振幅误差;2)由光学标度因子与各种器件参量关系表明开环解调时陀螺的线性误差较大.试验样机证明了以上结果,并找出减小漂移的方法. 相似文献