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131.
Markovian and semi-Markovian random processes are used to analyze the problem of optimal search for signals in a multichannel
communication system with arbitrarily distributed random outputs. The search efficiency factor is found in explicit form based
on state space merging, and a mathematical programming problem is set up to find a numerical suboptimal solution.
__________
Translated from Kibernetika i Sistemnyi Analiz, No. 3, pp. 144–150, May–June 2007. 相似文献
132.
The critical importance of studies of alternative methods of representation and processing of signals constructed from pseudorandom sequences of maximal period is demonstrated. For the first time, it is proposed that a multidimensional nonlinear finite-difference representation of an arbitrary pseudorandom sequence be employed. A suboptimal algorithm for nonlinear discrete Kalman filtration of a pseudorandom sequence is obtained. A numerical example of filtration of a sequence formed on the basis of a given recurrence rule is considered and its efficiency is demonstrated. 相似文献
133.
The importance of studies of alternative (as compared to traditional) methods of nonlinear stochastic parametric identification is demonstrated. Synthesis of a procedure of identification of the parameter, “discrete observer,” with the use of the criterion, “minimum probability of estimation error,” is proposed for the first time. A model example that demonstrates the efficiency of the proposed approach is considered. 相似文献
134.
介绍PAL制彩色全电视信号中色同步信号编码原理及恢复逐行倒相副载波的过程中,两种计算色同步信号相位角的方法。并且在实验的基础上得出:最小二乘法在PAL制电视信号的副载波相位角计算中不仅可以满足精度要求,而且简便灵活。 相似文献
135.
Chakraborty DP 《Journal of the Society for Information Display》2006,14(10):921-926
Researchers have developed visual discrimination models (VDMs) that can predict a human observer's ability to detect a target object superposed on an image. These models incorporate sophisticated knowledge of the properties of the human visual system. In the predictive approach, termed conventional VDM usage, two input images with and without a target are analyzed by an algorithm that calculates a just-noticeable-difference (JND) index, which is a taken as a measure of the detectability of the target. A new method of using the VDM is described, termed channelized VDM, which involves finding the linear combination of the VDM-generated channels (which are not used in conventional VDM analysis) that has optimal classification ability between normal and abnormal images. The classification ability can be measured using receiver operating characteristic (ROC) or two alternative forced choice (2AFC) experiments, and in special cases they can also be predicted by signal detection theory (SDT) based model-observer methods. In this study simulated background and nodule containing regions were used to validate the new method. It was found that the channelized VDM predictions were in excellent qualitative agreement with human-observer validated SDT predictions. Either VDM method (conventional or channelized) has potential applicability to soft-copy display optimization. An advantage of any VDM-based approach is that complex effects, such as visual masking, are automatically accounted for, which effects are usually not included in SDT-based methods. 相似文献
136.
Quantitatively describing the signal transduction process is important for understanding the mechanism of signal regulation
in cells, and thus, poses both a challenge and an opportunity for chemical and biochemical engineers. An artificial neural
network (ANN), in which we took the signal molecules as neural nodes, was constructed to simulate the generation of active
oxygen species (AOS) in Taxus chinensis cells induced by a bio-elicitor. The relative contents of AOS in cells predicted by the ANN model agreed well with the experimental
data and three notable stages of AOS increase were observed from the 3D figure of AOS generation. The robustness of AOS trajectories
indicated that signal regulation in vivo was an integral feedback control model that ensured the adaptation of Taxus chinensis to environmental stress. The artificial neural network was able to predict taxol production as well as determine the optimal
concentration of oligosaccharides needed for it. 相似文献
137.
动态信号分析系统的进展及应用 总被引:3,自引:0,他引:3
本文综述了动态信号分析仪器与系统的发展,并综合介绍了双通道动态信号分析仪的构成、性能与指标,以及由动态测量、数据采集、信号处理等硬件与相应软件组成的多通道动态信号分析系统的进展. 相似文献
138.
139.
基于信号样本可以重建信号频谱包络,本文提出一种简单、实用的内插方法,将此方法的有效性和FFT的优越性结合起来应用于细化频率分辨率,以适应需要获取信号较多频谱信息的应用场合。 相似文献