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211.
The mean density of bacteria in a water body is commonly monitored using quantal assay. This paper describes the use of local scoring in estimating the spatial distribution of mean density from quantal assay results at a set of point locations. An application to estimating the mean density of fecal conform bacteria in a coastal pond is presented. Model diagnostics based on a parametric bootstrap are also presented.  相似文献   
212.
The authors consider the issue of map positional error, or the difference between location as represented in a spatial database (i.e., a map) and the corresponding unobservable true location. They propose a fully model‐based approach that incorporates aspects of the map registration process commonly performed by users of geographic informations systems, including rubber‐sheeting. They explain how estimates of positional error can be obtained, hence estimates of true location. They show that with multiple maps of varying accuracy along with ground truthing data, suitable model averaging offers a strategy for using all of the maps to learn about true location.  相似文献   
213.
通过对常见的田间三种渠道特性夏适应性分析,反应出推广U型砼槽的必要性。给我们今后在水利工程田间渠道结构形式的选用上,提供了帮助。  相似文献   
214.
Abstract:  The subject of this paper is to describe the complexity of relations between man and wild monkeys, which causes difficulties in forming a social consensus related to their conservation and management. To present how the relations are in everyday life, and how they are simplified in universal discursive spaces, interviews and a questionnaire survey have been conducted. As a result, it is clarified that there are three kinds of discursive spaces, that of politics, natural science, and residents. People who share the land with wild monkeys have various terms and stories about their relations with monkeys. The monkeys have various values in the discourse of residents, including many troubles. The existence of monkeys is vivid and close, and can be described as "accessible" nature. However, in discussion of politics or natural sciences, there is less diversity in monkeys' values. In these discursive spaces, monkeys are described simply in the framework of "distant" nature, and wild monkey issues are constructed as a "pest animal issue". The simplified protocol between accessible and distant nature makes the wild monkey issues simple. And the attitudes of residents are shown as controversial through the contradiction between simple-complex issues. In conclusion, this contradiction cannot be solved only by filling the gap between accessible and distant nature with social consensus, but also by connecting the two and enhancing the dynamism of society as a whole.  相似文献   
215.
本文研究了等效法在中学物理教学中的应用,并结合一些具体实例进行了分析,对中学物理教学有一定指导意义。  相似文献   
216.
This paper documents situations where the variance inflation model for outliers has undesirable properties. The model is commonly used to accommodate outliers in a Bayesian analysis of regression and time series models. The alternative approach provided here does not suffer from these undesirable properties but gives inferences similar to those of the variance inflation model when this is appropriate. It can be used with regression, time series, and regression with correlated errors in a unified way, and adheres to the scientific principle that inference should be based on the data after obvious outliers have been discarded. Only one parameter is required for outliers; it is interpretable as the a priori willingness to remove observations from the analysis.  相似文献   
217.
Formulae are provided that define the ‘bend points’, the beginning and end of the essentially linear dose–response region, for the four‐parameter logistic model. The formulae are expressed in both response and dose units. The derivation of the formulae is shown in order to illustrate the general nature of the methodology. Examples are given that describe how the formulae may be used while planning and conducting bioassays. Copyright © 2003 John Wiley & Sons, Ltd.  相似文献   
218.
证交所国债买断式回购交易的风险研究   总被引:1,自引:0,他引:1  
国债买断式回购的推出衍生了抛补套利、循环融券卖空、债券组合交易、买断式回购组合交易这几种新的主要交易模式,丰富了投资者的交易手段,然而,这些新的交易模式将容易引发做空风险、流动性风险和更大的信用风险,在分析这些风险的基础上,提出了建立健全保证金制度、信用评估制度以及制定严格的交易规则等风险防范对策。  相似文献   
219.
语言风格体现一定的审美观,毛泽东的语言风格体现了他独有的审美取向和审美价值。这里通过对毛泽东生活实践和写作实践中所形成的伟人风采的展示和文风、语言风格的研究,将毛泽东的语言风格概括为通俗平易,形象生动;理中寓情,情理交融;想象丰富,气势磅礴;古为今用,推陈出新,为人们树立了语言艺术运用的光辉典范。  相似文献   
220.
一、电视新闻访谈节目和国内外研究现状1.电视新闻访谈节目电视新闻访谈节目,是一种新闻性题材的电视专题访问,也是电视新闻作深度报道的形式。新闻访谈作为一种广播电视新闻体裁,有别于别的基于互动的电视节目,如“脱口秀”(talk show)、电视辩论(debate)等。新闻访谈节目主要  相似文献   
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