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51.
Abnormalities in the cochlear function usually cause broadening of the auditory filters which reduces the speech intelligibility. An attempt to apply a spectral enhancement algorithm has been undertaken to improve the identification of Polish vowels by subjects with cochlear-based hearing-impairment. The identification scores of natural (unprocessed) vowels and spectrally enhanced (processed) vowels has been measured for hearing-impaired subjects. It has been found that spectral enhancement improves vowel scores by about 10% for those subjects, however, a wide variation in individual performance among subjects has been observed. The overall vowels identification scores obtained were 85% for natural vowels and 96% for spectrally enhanced vowels.  相似文献   
52.
By optimizing pump power ratio between 1st order backward pump and 2nd order forward pump on discrete Raman amplifier, we demonstrated over 2dB noise figure improvement without excessive non-linearity degradation.  相似文献   
53.
光学偏振实验仿真设计   总被引:1,自引:0,他引:1  
采用计算机工具软件,成功地设计和编制了偏振现象实验的仿真程序,用于计算机辅助教学  相似文献   
54.
The Kα to Lα and Kβ to Lβ intensity ratios of seven elements have been measured following photoionization at 59.5 keV by using a Si (Li) detector (FWHM=155 eV at 5.96 keV). The intensity ratios were determined by measuring K and L x-rays emitted from a standard target of a given element. The theoretical values of the Kα to Lα and Kβ to Lβ intensity ratios were calculated using theoretically tabulated values of shell/subshell photoionization cross sections, fluorescence yields, Coster-Kronig transition probabilities, and radiative decay rates for ηKLi≠ and ηKLi=0. The measured values are in good agreement with theoretical results. From Optika i Spektroskopiya, Vol. 97, No. 2, 2004, pp. 186–189. Original English Text Copyright ? 2004 by A. Kü?ük?nder, S?ğüt, E. Kü?ük?nder, Büyükkasap. This article was submitted by the authors in English.  相似文献   
55.
In this paper, we present some counterexamples which show that there is no theory on the spectrum of homogeneous compact operators which parallels the Riesz-Schauder theory on the spectrum of linear compact operators. These counterexamples also illustrate that it is impossible to study in a unified setting the Fucik spectrum of the Laplacian: -△w = au+ - bu- inΩand u = 0 on (?)Ω, as well as the spectrum of the p-Laplacian: -div(|(?)u| p-2(?)u) = λ|u|p-2u and u = 0 on (?)Ω.  相似文献   
56.
Parameters of Gaussian multivariate models are often estimated using the maximum likelihood approach. In spite of its merits, this methodology is not practical when the sample size is very large, as, for example, in the case of massive georeferenced data sets. In this paper, we study the asymptotic properties of the estimators that minimize three alternatives to the likelihood function, designed to increase the computational efficiency. This is achieved by applying the information sandwich technique to expansions of the pseudo-likelihood functions as quadratic forms of independent normal random variables. Theoretical calculations are given for a first-order autoregressive time series and then extended to a two-dimensional autoregressive process on a lattice. We compare the efficiency of the three estimators to that of the maximum likelihood estimator as well as among themselves, using numerical calculations of the theoretical results and simulations.  相似文献   
57.
In this paper, by using elementary analysis, we establish some new Lyapunov-type inequalities for nonlinear systems of differential equations, special cases of which contain the well-known equations such as Emden-Fowler-type and half-linear equations. The inequalities obtained here can be used as handy tools in the study of qualitative behaviour of solutions of the associated equations.  相似文献   
58.
The crystal structure of 1-[3-(3,4-dimethoxyphenyl)-2-propenoyl]pyrrolidine (C15H19NO3) (I) has been determined by X-ray analysis. It crystallizes orthorhombic space group Pbca with a = 24.295(3), b = 15.086(3), c = 7.552(3)A, V = 2768(1)A3, Z = 8, Dcalc = 1.254 g/cm3, mu = (Mo K(alpha)) = 0.87 cm(-1). The title compound has analgesic activity of cycloaliphatic amine part. The molecule is deviated from planar configuration.  相似文献   
59.
60.
四种多变量校准方法在FTIR多组分分析中的性能比较   总被引:1,自引:0,他引:1  
本文对四种多变量校准方法--经典最小二乘法(CLS),偏最小二乘法(PLS),卡尔曼滤波法(KFM)以及人工神经网络法(ANN)--在多组分浓度分析方面的性能进行了比较。选择五种红外谱图严重混叠的大气有机毒物--1,3-丁二烯,苯,邻二甲苯,氯苯和丙烯醛--作为分析对象。分别计算各种方法对该5组分体系的平均预测误差MPE和平均相对误差MRE进行比较。结果表明,偏最小二乘法在处理这类问题中是最稳健的方法。  相似文献   
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