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961.
曲线箱梁桥实用设计方法的研究   总被引:2,自引:0,他引:2  
曲线箱梁桥目前还缺乏比较实用的设计方法.本文对曲线箱梁桥的现有设计方法作了研究,并推荐一种实用设计方法:采用空间梁单元,每个节点取六个自由度;等效梁格的模拟考虑了横向梁格附近有无横隔梁的情况.结果证明,这是一种简便、较精确的设计方法.  相似文献   
962.
This study examines a key component of environmental risk communication; trust and credibility. The study was conducted in two parts. In the first part, six hypotheses regarding the perceptions and determinants of trust and credibility were tested against survey data. The hypotheses were supported by the data. The most important hypothesis was that perceptions of trust and credibility are dependent on three factors: perceptions of knowledge and expertise; perceptions of openness and honesty; and perceptions of concern and care. In the second part, models were constructed with perceptions of trust and credibility as the dependent variable. The goal was to examine the data for findings with direct policy implications. One such finding was that defying a negative stereotype is key to improving perceptions of trust and credibility.  相似文献   
963.
Estimation from Zero-Failure Data   总被引:2,自引:0,他引:2  
When performing quantitative (or probabilistic) risk assessments, it is often the case that data for many of the potential events in question are sparse or nonexistent. Some of these events may be well-represented by the binomial probability distribution. In this paper, a model for predicting the binomial failure probability, P , from data that include no failures is examined. A review of the literature indicates that the use of this model is currently limited to risk analysis of energetic initiation in the explosives testing field. The basis for the model is discussed, and the behavior of the model relative to other models developed for the same purpose is investigated. It is found that the qualitative behavior of the model is very similar to that of the other models, and for larger values of n (the number of trials), the predicted P values varied by a factor of about eight among the five models examined. Analysis revealed that the estimator is nearly identical to the median of a Bayesian posterior distribution, derived using a uniform prior. An explanation of the application of the estimator in explosives testing is provided, and comments are offered regarding the use of the estimator versus other possible techniques.  相似文献   
964.
The aim of this case study is to discuss the role of technology in addressing environmental problems. The paper tries to scratch beneath the surface of the increasingly frequent ‘quick-fix’ solutions to the present environmental problems, based on such beguiling catchwords as Cleaner Technologies, Best Available Technologies, and Best Available Technologies Not Exceeding Excessive Costs, etc., in an attempt to discover whether there is any substance in them, or whether they are just full of hot air. Recent data from case studies performed by the author in Germany and Finland as well as a postal questionnaire in Denmark are presented. The paper analyses and discusses the roles and responsibilities of designers, industrialists, and government policy-makers. It is argued that existing regulatory regimes, supranational industrial structures, and market mechanisms do not favour the development of cleaner technologies, nor do they promote a reduction in consumption patterns. Evidence from ongoing empirical research in Northwest Europe suggests that industry is far from developing and/or implementing cleaner technologies. The paper closes with a discussion of some of the policy implications involved and some examples of urgently needed further research.  相似文献   
965.
Application of software for manufacturing processes is one of the resolutions many enterprises have resorted to in the 21st century. This has been a result of increased complexity of products, globalization, rapid changes in technology and so on. The idea was that application of software especially for product development would increase the competitive advantage of industry nevertheless the irony has been that most of the investment in software has not achieved the expected results. We carry out a case study to introduce a methodology, the analytical network process as a multiattribute strategic decision making approach to help in the selection of appropriate software to suit the product development process of a particular product.  相似文献   
966.
The close alignment of applied research and development units with manufacturing operational structures can provide excellent opportunities for maintaining robust product pipelines and reducing product development cycle times. Within such an integrated organizational model (IOM), however, lies a potentially disruptive psychological mechanism that can lead to the dissolution of this delicate partnership if it is not handled properly. This mechanism is cognitive gap, which can take several basic forms: first, as differences between the nature and difficulty of the problem at hand and the cognitive resources of the problem solvers tasked with its solution; and second, as differences between the cognitive abilities and approaches of the problem solvers themselves. In this paper, we define and discuss cognitive gap within the context of Kirton's Adaption-Innovation theory, a useful framework for understanding problem solving (and problem solvers) in general. Specific implications (both favourable and potentially destructive) of cognitive gaps for high performance product development organizations are discussed, and suggestions for their effective management are offered.  相似文献   
967.
当代生活与艺术之死:第二、第三和第一世界   总被引:1,自引:0,他引:1  
当今所谓的艺术,主要是受20世纪七八十年代以来发展并在全球范围内扩散的美国式“艺术”观念所支配,而再也不受德语的“艺术”或法语的“美的艺术”体系所支配。自从现代主义诞生以来,艺术的历史使命的减弱或者消失已经成为事实,但从全球范围而言,“艺术的终结”这一论断仍有些夸大其词。因为在第一世界的艺术死亡之后(这里存在更多的是文化),第二和第三世界的艺术还生长着。艺术从根本上说还不是一个媒介事件和现象,而是一个同我们每个人相关的东西——不管它是不是商品。  相似文献   
968.
制造企业服务业务扩展及其认知因素研究   总被引:9,自引:1,他引:9  
制造企业的竞争越来越激烈,几乎所有的企业都要面对快速反应多变市场和应对价格压力的要求,面对越来越小的产品利润空间和越来越复杂的客户需求,本文从对工业服务管理文献分析和制造企业的调查研究入手,揭示了制造企业从纯粹的产品生产者向客户支持方案提供者发展的转移趋势.通过对瑞士和德国30多家机器和设备制造企业进行的调查研究,说明了服务业务对制造企业在开发财务、营销和战略机会上的重要作用,并对转移过程中服务业务的扩展过程进行了总结.结合具体企业实践,本文对制约制造企业扩展服务业务中在管理动机上的认知因素进行了分析和研究.结合中国加入WTO后,中国制造企业将全面融入国际竞争的背景,本文期望对中国制造企业的发展和竞争地位的提高提供理论和实践上的指导.  相似文献   
969.
区域产品分类与选择是区域经济发展中最重要和最基础的工作.在产品选择与分类时,需要确定指标权系数和分类阈值等参数,这在实际应用中是比较困难的.针对这种情况,提出了一种信息不完全确定的区域产品模糊区间聚类方法.该方法构建了指标权系数信息不完全确定的最优模糊区间聚类模型,利用遗传算法和改进的FCM算法联合求解所得优化模型,得到指标权系数、最优聚类中心和最优划分,进而确定各产品所属类别.最后将该方法应用于某区域的产品分类和主导产品的确定中,实例计算说明该方法的可行性和有效性.  相似文献   
970.
基础研究学科发展的宏观知识挖掘   总被引:3,自引:0,他引:3  
本文提出了一种学科发展分析的宏观知识挖掘思路和方法.从整体上、宏观上对蕴含于基础研究项目建议书(Proposal)中的知识进行挖掘,并在挖掘的基础之上对基础研究的学科发展趋势、特点,学科领域的分化、融合以及交叉等进行分析,并从学科整体、学科领域和项目等三个层面对基础研究的科研管理工作提供基于知识的决策支持.  相似文献   
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