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991.
谋划城镇的发展,首先应搞清楚我们的经济高地在哪里,有的放矢,才能减少决策失误,降低开发成本,加快发展速度,提高经济质量,实现科学发展。在全球化时代,我们要积极构筑“三大经济发展高地”,才能占领制高点,掌握经济发展的话语权和主动权。  相似文献   
992.
期刊装帧设计是高校装帧设计教学中的一门重要课程,跟市场的变化有着密切的关系,研究市场变化才能为教学内容的设置“有的放矢”。本文拟就期刊装帧设计在市场上出现的新问题作一研究,以利期刊装帧设计教学的完善和对广大学习期刊装帧设计学生予以积极引导。  相似文献   
993.
Let fn(x) be the univariate k-nearest neighbor (k-NN) density estimate proposed by Loftsgaarden and Quesenberry (1965). By using similar techniques as in Bahadur's representation of sample quantiles (1966), and by the recent results on the oscillation of empirical processes by Stute (1982), we derive the rate of strong uniform convergence of fn(x) on some suitably chosen interval Jδ. Some comparison with the kernel estimates is given, as well as the choice of the bandwidth sequence relative to the sample size.  相似文献   
994.
Every bivariate distribution function with continuous marginals can be represented in terms of a unique copula, that is, in terms of a distribution function on the unit square with uniform marginals. This paper is concerned with a special class of copulas called Archimedean, which includes the uniform representation of many standard bivariate distributions. Conditions are given under which these copulas are stochastically ordered and pointwise limits of sequences of Archimedean copulas are examined. We also provide two new one-parameter families of bivariate distributions which include as limiting cases the Frechet bounds and the independence distribution.  相似文献   
995.
By a family of designs we mean a set of designs whose parameters can be represented as functions of an auxiliary variable t where the design will exist for infinitely many values of t. The best known family is probably the family of finite projective planes with υ = b = t2 + t + 1, r = k = t + 1, and λ = 1. In some instances, notably coding theory, the existence of families is essential to provide the degree of precision required which can well vary from one coding problem to another. A natural vehicle for developing binary codes is the class of Hadamard matrices. Bush (1977) introduced the idea of constructing semi-regular designs using Hadamard matrices whereas the present study is concerned mostly with construction of regular designs using Hadamard matrices. While codes constructed from these designs are not optimal in the usual sense, it is possible that they may still have substantial value since, with different values of λ1 and λ2, there are different error correcting capabilities.  相似文献   
996.
997.
An approach, using biomarkers (biological responses) for assessing the biological and ecological significance of contaminants present in the environment is described. Living organisms integrate exposure to contaminants in their environment and respond in some measurable and predictable way. Responses are observed at several levels of biological organization from the biomolecular level, where pollutants can cause damage to critical cellular macromolecules and elicit defensive strategies such as detoxication and repair mechanisms, to the organismal level, where severe disturbances are manifested as impairment in growth, reproduction, developmental abnormalities, or decreased survival. Biomarkers can provide not only evidence of exposure to a broad spectrum of anthropogenic chemicals, but also a temporally integrated measure of bioavailable contaminant levels. A suite of biomarkers are evaluated over time to determine the magnitude of the problem and possible consequences. Relationships between biomarker response and adverse ecological effects are determined from estimates of animal health and population structure.  相似文献   
998.
We show that sup, completely as, where f is a uniformly continuous density on are independent random vectors with common density f, and fn is the variable kernel estimate Here Hni is the distance between Xi and its kth nearest neighbour, K is a given density satisfying some regularity conditions, and k is a sequence of integers with the property that log asn  相似文献   
999.
In the present paper we are going to extend the likelihood ratio test to the case in which the available experimental information involves fuzzy imprecision (more precisely, the observable events associated with the random experiment concerning the test may be characterized as fuzzy subsets of the sample space, as intended by Zadeh, 1965). In addition, we will approximate the immediate intractable extension, which is based on Zadeh’s probabilistic definition, by using the minimum inaccuracy principle of estimation from fuzzy data, that has been introduced in previous papers as an operative extension of the maximum likelihood method.  相似文献   
1000.
本文以机械企业为背景,探讨了一人多机看管问题中的人员配置问题,并采用层次序列法对人员配置数学模型进行了求解,给出了启发式解法,指出了进一步研究的方向。  相似文献   
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