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51.
Problems of optimum hanging of long rotor blades of the last stages of steam turbines are considered. Causes of nonuniform erosion wear of the inlet edges connected with inaccurate location of holes for the external damper coupling on the chord of the profile are determined. Methods for optimizing the hanging of blades for raising the reliability of the last stages are suggested. Main results of hanging performed with the help of a specially developed “LIBRA” soft hardware are presented. __________ Translated from élektricheskie Stantsii, No. 11, November 2006, pp. 36–41.  相似文献   
52.
王威 《水利电力机械》2007,29(11):1-5,7
黄埔发电厂#6发电机转冷水铜离子含量超标,通过对缺陷原因进行分析,针对二级水封的特性对溢出的转冷水进行回收并利用化学凝结水处理去除溶出的铜离子,通过控制转冷水的pH值最终减缓铜管的腐蚀.  相似文献   
53.
The paper introduces the highly problematic nature of modelling in design and technology education and examines the relationship between cognitive and concrete modelling. Its aim is to gain insight into what learners do, rather than what others say they ought to do in their learning activities. The variety of purposes that educators have for learners’ modelling are discussed through examining the contested curriculum justification for design and technology education itself. The paper proposes that learners’ modelling cannot be extracted from the social milieu in which they act and it provides some insights of these social influences through the analysis of two case studies. Their settings are a girls’ secondary school and a college of higher education. Each case study is presented independently but organised with a common format to consider a) the impact of assessment on learning intentions and outcomes; b) cultural influences on learning and modelling; c) social influences on learning and modelling. A discussion of the emergent themes considers implications for teachers. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
54.
黄燕  陈晖 《人民长江》2002,33(11):10-11,37
宜昌水文站是葛洲坝、三峡水利枢纽的设计依据站。葛洲坝水利枢纽动工修建和运行 ,对该站水位流量关系中低水部分产生了影响。探讨了该河段泄流能力的变化对葛洲坝水利枢纽设计洪水有无影响的问题。用1 967~ 1 999年实测资料对宜昌站以汛期平均水位为参数的水位流量关系曲线簇进行了检验 ,大部分年份最大日平均流量、3、7、1 5、30d洪量的偏差在± 4 %之间 ,说明曲线簇推流具有相当的精度。证明了宜昌河段中低水泄流能力的变化对葛洲坝水利枢纽设计流量和校核流量基本没有影响  相似文献   
55.
李学宁 《江西水利科技》2002,28(3):144-145,156
针对堤防设计的基础资料采集和设计优化,提出了一些合理性建议。  相似文献   
56.
In this paper we illustrate how certain design problems can be simplified by reparametrization of the response function. This alternative viewpoint provides further insights than the more traditional approaches, like minimax, Bayesian or sequential techniques. It will also improve a practitioner’s understanding of more general situations and their “classical” treatment.  相似文献   
57.
在对我国铁路技术站运输分析手段和管理信息资源进行分析的基础上,提出技术站运输分析管理信息系统的设计,充分利用和整合技术站铁路运输管理信息系统(TMIS)和办公自动化网络等信息资源,实现统计工作自动化、分析工作网络化和车站作业组织的动态模拟,准确、即时地分析车站运输生产情况,挖掘潜能,为决策提供适时、可靠的依据,适应运输市场的快速变化。  相似文献   
58.
Strategic management research has been characterized as placing less emphasis on construct measurement than other management subfields. In this work, we document the state of the art of measurement in strategic management research, and discuss the implications for interpreting the results of research in this field. To assess the breadth of measurement issues in the discipline, we conducted a content analysis of empirical strategic management articles published in leading journals in the period of 1998–2000. We found that few studies discuss reliability and validity issues, and empirical research in the field commonly relies on single‐indicator measures. Additionally, studies rarely address the problems of attenuation due to measurement error. We close with a discussion of the implications for future research and for interpreting prior work in strategic management. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   
59.
结合建设项目进度及质量控制理论,从施工方案、进度计划、施工组织及劳动力计划、材料及施工设备、质量保证及安全生产等方面论述了大坝安全监测自动化系统工程的施工组织设计,对提高系统的可靠性、缩短工期、节约投资具有一定的现实意义.  相似文献   
60.
As part of the reforms of their systems for financing and delivering health care, many transition economies, particularly in central and eastern Europe, have adopted national insurance funds that are institutionally separate from ministries of health. Most of these countries have also grappled with the problem of restructuring the delivery system, especially the need to reduce hospital capacity. Although improving the performance of medical care providers through a shift from passive budgeting to explicitly incentive mechanisms is important, why this change in financial relations between the government and providers could not be implemented simply by reforming the role of health ministries is not obvious. This paper presents an explicit rationale for the separation of powers between the regulator (the ministry of health) and the financing body (the insurance fund), based on the inability of a single agency to commit to closing hospitals. JEL classification: L51, P20, P35, I18.  相似文献   
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