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31.
沁水煤田瓦斯含量与地质因素的关系   总被引:1,自引:0,他引:1  
刘国伟 《山西煤炭》2003,23(4):14-15
为确实做好瓦斯的洲报工作,研究了沁水煤田地质因素与瓦斯含量的关系,辩证地分析了瓦斯的赋存规律。  相似文献   
32.
In their comments on the authors' article (see record 2003-10163-009), R. C. Serlin, B. E. Wampold, and J. R. Levin (see record 2003-10163-011) and P. Crits-Christoph, X. Tu, and R. Gallop (see record 2003-10163-010) took issue with the authors' suggestion to evaluate therapy studies with nested providers with a fixed model approach. In this rejoinder, the authors' comment on Serlin et al's critique by showing that their arguments do not apply, are based on misconceptions about the purpose and nature of statistical inference, or are based on flawed reasoning. The authors also comment on Crits-Christoph et al's critique by showing that the proposed approach is very similar to, but less inclusive than, their own suggestion. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
33.
The successful initiation and execution of a virtual team is gaining increasing attention in the design and construction community. From opportunities to integrate international and multidisciplinary teams to the opportunity to leverage the best resources in an organization on a given project, virtual teams can transform the concept of project planning and execution. However, potential barriers exist in several areas to the successful implementation of virtual teams. The needs of increased management emphasis, social and cultural understanding, and emphasis on common goals are only a few of the nontechnical factors that can turn successful virtual teaming into virtual frustration. When combined with traditional technical challenges including compatibility of systems, security, and the selection of appropriate technologies, the line between leveraging virtual technologies for enhanced solutions and introducing additional complications into the project process is one that can be easily crossed. This paper presents the findings of research that addresses the opportunities and potential barriers to successful virtual teams in the engineering, procurement, and construction industry. Combining results from current research, industry practices, and early results from nonconstruction industries, the research findings provide an initial path to successful virtual team implementation.  相似文献   
34.
Capital cost correlations are given for oil-water separators, equalization basins, primary clarifiers, clarifiers and clarifier mechanisms, reverse osmosis unit, ultrafiltration units, gravity filters and miroscreens. Data are included for raw sewage, intermediate and recirculation pumping stations and for preliminary treatment (or bar screens, grit removal, overflow and bypass chamber and Parshall flume), for grit removal, comminution and gas stripping. The correlations are accurate to ± 30%, expressed in Canadian dollars and adjusted to a Marshall and Swift value of 1000. Details as to what components are included in the cost are given. Data are given for the labour and material costs to create a working process module. For inflation indices, a critique of the Engineering News Record, EPA small city, Marshall and Swift, Chemical Engineering and Southam inflation indices suggested that the Marshall and Swift index is most appropriate for the construction and process equipment studied here. Concerning the currency exchange, for the equipment and processes in this study, equipment costs the same whether expressed directly in US or Canadian dollars. To put the current data into perspective, several hundred sources of cost data were analyzed. The major correlations are compared, on a consistent basis, with current data.  相似文献   
35.
The UK Government has supported a programme on Renewable Energy since 1975. In 1988 progress was reviewed and this led to some redirection of the programme with greater emphasis on the commercial development of renewables, as published in Energy Paper 55.The climate in which Renewable Energy operates has been influenced recently by a number of factors including privatisation of the UK electricity supply industry, when the Government introduced the New Fossil Fuel Obligation and publication of the Government's 1990 White Paper on the Environment which noted that the Government is working towards a figure of new renewable energy generating capacity of 1000 MW by 2000.The paper aims to give an overview of the present state of development of the renewable technologies in the UK and to discuss some of the factors - technical and non-technical - which will affect their likely future development.  相似文献   
36.
近年来,随着创新性技术的不断应用,硬盘驱动器的气膜浮动块(以下简称浮动块)也有了较大改进,例如浮动块表面的设计越来越精巧,而性能却更加稳定。因此很好的理解哪些因素是影响气膜浮动块浮动特性的主要原因显得尤为重要。分析这些因素对浮动块的影响结果,有利于我们改进浮动块的特性并对其发展前景做出预测,本文对这些影响因素做了概括总结。  相似文献   
37.
通过有限元的方法,分析了T型薄壁管节点受平面内弯矩作用下的疲劳行为,得到了应力最大值的位置和拟合出用于预测T型薄壁管节点受平面内弯矩作用下的应力集中系数的参数公式。  相似文献   
38.
用Nardini-Brebbia边界元法计算了动载荷下的应力强度因子,与解析解及有限元解相比较,效果较好。最后对计算结果进行了分析讨论。  相似文献   
39.
Stress concentration and fatigue of profiled reinforcing steels   总被引:1,自引:0,他引:1  
Stress concentrations arise from profiles of ribbed reinforcing steel bars and in this study the results of calculated stress concentration factors (SCF), by using finite element method, are related to the fatigue test results. It is apparent that the degree of confinement of a ribbed bar embedded in concrete not only affects the magnitude of the ultimate bond stress but also the bond stress-slip relation. Thus the rib geometry or profile pattern is designed for optimum bond characteristics and not for fatigue considerations. However the rib geometry influences the fatigue performance through the SCFs arising from the root radius, width and flank angles of the profiles. It is shown that these latter factors have a significant influence on the fatigue behaviour of reinforcing steel bars.  相似文献   
40.
The lockdown due to COVID-19 in Italy resulted in the sudden closure of schools, with a shift from traditional teaching to the online one. Through an online questionnaire, this survey explores teachers' experience of online teaching, the level of risk factors (e.g., stress) and protective factors (e.g., locus of control) and their impact on satisfaction levels during the social distancing. One hundred seven high school teachers from Lombardy, an Italian region very affected by the COVID-19 outbreak, participated. Results show that depression and stress are the main predictors of satisfaction levels for online teaching. In addition, coping, locus of control and self-efficacy emerge as important protective factors. Finally, although there is great satisfaction with the online teaching experience, critical elements emerged. This study is relevant because it describes the critical elements of the online teaching experience, and identifies some protective factors and the main risk factors in teachers operating in an area strongly marked by social restrictions imposed by the pandemic. High school teachers emerge as a sub-group of the general population with specific psychological reactions. Considering the results, it is possible to suggest providing high-quality educational support and crisis-psychological oriented services to teachers, and help to maintain the psychological well-being.  相似文献   
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