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91.
Summary Weak disintegrations are investigated from various points of view. Kolmogorov's definition of conditional probability is critically analysed, and it is noted how the notion of disintegrability plays some role in connecting Kolmogorov's definition with the one given in line with de Finetti's coherence principle. Conditions are given, on the domain of a prevision, implying the equivalence between weak disintegrability and conglomerability. Moreover, weak sintegrations are characterized in terms of coherence, in de Finetti's sense, of, a suitable function. This fact enables us to give, an interpretation of weak disintegrability as a form of “preservation of coherence”. The previous results are also applied to a hypothetical inferential problem. In particular, an inference is shown to be coherent, in the sense of Heath and Sudderth, if and only if a suitable function is coherent, in de Finetti's sense. Research partially supported by: M.U.R.S.T. 40% “Problemi di inferenza pura”.  相似文献   
92.
介绍了在工程界已广泛应用的信号分析诊断及尚停留在实验室探索的裂纹分析诊断,模糊分析诊断的工作原理和应用实例。  相似文献   
93.
顾客价值创新:战略分析的基点   总被引:17,自引:0,他引:17  
传统的战略分析是以竞争为基点的。其目的是如何比竞争对手做得更好。在这种思维指导下 ,企业经营往往产生竞争激烈、市场不敏感、反应性行为、缺乏创新等后果。在复杂多变的环境中 ,战略分析应转移到顾客价值创新上来。顾客价值创新战略通过为顾客提供完全新型或得到重大改进的价值而使企业经营与竞争无关。顾客价值创新战略与竞争基点战略在战略导向、对竞争的认知及态度、企业本身实力的认识等具有明显不同的特征 ;进行顾客价值创新可以按照顾客价值创新循环机制进行 ,这一循环机制以顾客消费流程分析为起点 ,由创新机会认别、资源需求分析及价值创新实施等环节构成。  相似文献   
94.
从移民的基本政策、移民安置规划、公众参与、移民的组织机构及责任四个方面 ,对中国移民政策与亚洲银行移民政策进行了对比分析 ,找出之区别 ,以便更好地与国际接轨  相似文献   
95.
Beryllium is the strongest of the lightweight metals. Used primarily in military applications prior to the end of the Cold War, beryllium is finding new applications in many commercial products, including computers, telecommunication equipment, and consumer and automotive electronics. The use of beryllium in nondefense consumer applications is of concern because beryllium is toxic. Inhalation of beryllium dust or vapor causes a chronic lung disease in some individuals at concentrations as low as 0.01 microg/m3 in air. As beryllium enters wider commerce, it is prudent to ask what risks this might present to the general public and to workers downstream of the beryllium materials industry. We address this question by evaluating the potential for beryllium exposure from the manufacturing, use, recycle, and disposal of beryllium-containing products. Combining a market study with a qualitative exposure analysis, we determine which beryllium applications and life cycle phases have the largest exposure potential. Our analysis suggests that use and maintenance of the most common types of beryllium-containing products do not result in any obvious exposures of concern, and that maintenance activities result in greater exposures than product use. Product disposal has potential to present significant individual risks, but uncertainties concerning current and future routes of product disposal make it difficult to be definitive. Overall, additional exposure and dose-response data are needed to evaluate both the health significance of many exposure scenarios, and the adequacy of existing regulations to protect workers and the public. Although public exposures to beryllium and public awareness and concern regarding beryllium risks are currently low, beryllium risks have psychometric qualities that may lead to rapidly heightened public concern.  相似文献   
96.
To quantify the health benefits of environmental policies, economists generally require estimates of the reduced probability of illness or death. For policies that reduce exposure to carcinogenic substances, these estimates traditionally have been obtained through the linear extrapolation of experimental dose-response data to low-exposure scenarios as described in the U.S. Environmental Protection Agency's Guidelines for Carcinogen Risk Assessment (1986). In response to evolving scientific knowledge, EPA proposed revisions to the guidelines in 1996. Under the proposed revisions, dose-response relationships would not be estimated for carcinogens thought to exhibit nonlinear modes of action. Such a change in cancer-risk assessment methods and outputs will likely have serious consequences for how benefit-cost analyses of policies aimed at reducing cancer risks are conducted. Any tendency for reduced quantification of effects in environmental risk assessments, such as those contemplated in the revisions to EPA's cancer-risk assessment guidelines, impedes the ability of economic analysts to respond to increasing calls for benefit-cost analysis. This article examines the implications for benefit-cost analysis of carcinogenic exposures of the proposed changes to the 1986 Guidelines and proposes an approach for bounding dose-response relationships when no biologically based models are available. In spite of the more limited quantitative information provided in a carcinogen risk assessment under the proposed revisions to the guidelines, we argue that reasonable bounds on dose-response relationships can be estimated for low-level exposures to nonlinear carcinogens. This approach yields estimates of reduced illness for use in a benefit-cost analysis while incorporating evidence of nonlinearities in the dose-response relationship. As an illustration, the bounding approach is applied to the case of chloroform exposure.  相似文献   
97.
企业效益评价因子分析模型及应用   总被引:13,自引:4,他引:9  
本文将因子分析方法应用于社会科学领域的经济评价系统。从一些错综复杂的经济现象中找出少数几个主因子,每一个主因子代表经济变量之间相互依赖的一种经济作用,抓住这些主因子就可以帮助我们对复杂的经济问题进行分析和解释。在简要介绍因子模型以后,从实证分析的角度,选取深沪股市高科技板块 2 0家上市公司1998年中期的一系列经济评价指标,采用因子分析方法,并借助社会科学统计软件SPSS,进行企业的综合经济效益分析评价,得出因子分析是一种进行企业综合效益评价的有效方法。  相似文献   
98.
本文从理论上论证回转器是一种具有回转阻抗性能的传输元件,可用霍尔效应实现回转器。  相似文献   
99.
语篇分析与机器翻译   总被引:2,自引:0,他引:2  
机译系统应该建立在具有语篇分析的大型语料库基础之上,语篇语料库内的原语和目的语文本不是单向、而应是双向或多向流动的网络系统。文本的译文也应该有历时和共时的区别,因为互文性已是翻译的某种本质特征。  相似文献   
100.
计算结构力学课程的改革与学科发展   总被引:4,自引:1,他引:3  
文章介绍了计算结构力学教学改革的目的和意义,进一步确立了适应21世纪人才培养的学科教学内容与体系,在课程教学的改革中特别就结构分析的技术应用和创新能力培养等方面进行了探索。  相似文献   
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