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51.
52.
本文通过调整迭代解码过程中系统位接收值的加权系数,提出了一种Turbo码加权迭代解码算法。该算法改变了迭代运算后Turbo码解码器输出软值中系统位接收值信息和它的外部估计信息的比重,使Turbo码无论在低信噪比或是在高信噪比时均具有优良的纠错性能。仿真结果显示,采用Turbo码加权迭代解码算法,不仅能提高Turbo码的收敛速度,而且能进一步降低Turbo码解码时的地板值,使Turbo码的比特误码率在高、低信噪比时都能够得到进一步改善。 相似文献
53.
In the presented text the authors judge the importance of statistics in the monetary policy of the Czech National Bank (CNB) over the course of the economic transformation process, with particular consideration of changing statistical needs and the possibilities and limits of statistical data exploitation in the monetary analyses. The importance of statistics lies on the level of collection and processing of statistical information and on the level of use of statistical methods to analyse data. Since the start of the 1990s the requirements for statistics were significantly influenced by monetary policy. In the period 1990–1997, monetary targeting was the primary influential factor. Since 1998, the monetary policy is influenced by inflation targeting. Statistical priorities switched from monetary data to economy and financial market data. Much progress has been made in the use of statistical methods for analysing data. Statistics available at present cover the CNB's standard monetary-policy requirements and are on par with those in developed countries. Its further development will reflect the standard changes taking place in the more advanced countries. 相似文献
54.
潘凤焕 《北京市经济管理干部学院学报》2005,20(3):41-45,32
随着互联网的迅猛发展和广泛应用,日趋严重的网络信息安全问题,对政府管制提出了更为复杂和系统的要求,在此情况下,如何管制"爆炸式"发展的互联网,既使宪法所赋予公民的言论自由可以在网络上充分且方便地享有,又能够抑制侵害他人、国家乃至社会自由和效率的不正当行为,这成为摆在中国政府面前的一项重要课题.本文分析了网络信息安全与政府管制的关系,提出了网络信息安全政府管制的政策选择. 相似文献
55.
发展农业电子商务实现农业信息化 总被引:2,自引:0,他引:2
杨洋 《当代经理人(中旬刊)》2006,(10)
农业电子商务,作为先进的生产力,其潜在优势是不可忽略的。针对我国农业发展过程中面临的突出问题,提出农业电子商务是促进农业发展的强大推动力和客观需要。并研究了当前加快农业产业信息化进程中存在的困难并探讨了相应的解决策略。 相似文献
56.
57.
文章从科技人力资源、科技资金资源、科技物质资源和科技信息资源等方面分析了常德市科技资源配置的现状、存在的问题,并提出了相应的对策和建议。 相似文献
58.
Sample design and sample allocation methods are developed for random digit dialling in household telephone surveys. The proposed method is based on a two-way stratification of telephone numbers. A weighted probability proportional to size sample allocation technique is used, with auxiliary variables about the telephone coverage rates, within local telephone exchanges of each substrata. This makes the sampling design nearly “self-weighting” in residential numbers when the prior information is well assigned. A computer program generates random numbers for the local areas within the existing phone capacities. A simulation study has shown greater sample allocation gain by the weighted probabilities proportional to size measures over other sample allocation methods. The amount of dialling required to obtain the sample is less than for proportional allocation. A decrease is also observed on the gain in sample allocation for some methods through the increasing sample sizes. 相似文献
59.
In this paper, progressive stress accelerated life tests are considered when the lifetime of a product under use condition
follows a finite mixture of distributions. The experiment is performed when each of the components in the mixture follows
a general class of distributions which includes, among others, the Weibull, compound Weibull, power function, Gompertz and
compound Gompertz distributions. It is assumed that the scale parameter of each component satisfies the inverse power low,
the progressive stress is directly proportional to time and the cumulative exposure model for the effect of changing stress
holds. Based on type-I censoring, the maximum likelihood estimates (MLEs) of the parameters under consideration are obtained.
A special attention is paid to a mixture of two Rayleigh components. Simulation results are carried out to study the precision
of the MLEs and to obtain confidence intervals for the parameters involved. 相似文献
60.
We characterize the equilibrium of the all-pay auction with general convex cost of effort and sequential effort choices. We
consider a set of n players who are arbitrarily partitioned into a group of players who choose their efforts ‘early’ and a group of players who
choose ‘late’. Only the player with the lowest cost of effort has a positive payoff in any equilibrium. This payoff depends
on his own timing vis-a-vis the timing of others. We also show that the choice of timing can be endogenized, in which case
the strongest player typically chooses ‘late’, whereas all other players are indifferent with respect to their choice of timing.
In the most prominent equilibrium the player with the lowest cost of effort wins the auction at zero aggregate cost.
We thank Dan Kovenock and Luis C. Corchón for discussion and helpful comments. The usual caveat applies. Wolfgang Leininger
likes to express his gratitude to Wissenschaftszentrum Berlin (WZB) for its generous hospitality and financial support. 相似文献