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21.
对瑞利和非瑞利杂波中的单、双参数杂波图的控制虚警性能和检测性能进行了比较分析,并得到了双参数杂波图门限调整值的取值范围,得出了几点有益的结论。 相似文献
22.
轻型钢骨结构低层住宅设计荷载分析 总被引:1,自引:0,他引:1
本文讨论了北美低层钢骨结构住宅结构设计的荷载问题,包括各类荷载的取值和计算方法,以及荷载组合模式,并提出了在我国相关规范没有出台前,在国内进行设计时应该注意的一些问题。 相似文献
23.
A feasibility analysis methodology adopted from reactive distillation is applied to membrane reactors. A model is formulated to depict the reactive liquid phase composition on the retentate side of a continuous type membrane reactor. The effects of both the chemical reaction kinetics and the membrane mass transfer kinetics on the feasible products are elucidated by means of retentate phase diagrams and bifurcation analysis. The proposed method can be applied to various membrane processes, independent of the specific structure of the membrane. Two quaternary reaction systems are considered to illustrate the methodology. In the first hypothetical system, it is shown how selective membranes can influence the sequence of effective volatilities which in turn affects the feasible products of the system. In the second example of practical importance, i.e. the heterogeneously catalysed synthesis of propyl acetate coupled with permeation through a porous polycarbonate membrane, the dusty gas model is applied to describe the component fluxes through the membrane. For the latter reaction system, the existence of reactive arheotrope is demonstrated. Arheotropes represent mass transfer controlled feasible products of membrane separation process. 相似文献
24.
建筑工程中渗漏质量通病的原因及防治措施 总被引:1,自引:0,他引:1
对浴厕这一容易引发渗漏质量通病的环节作了原因分析,从严格精确预留管道洞口,严把材料关等方面,提出了相应的预防措施,并指出治理渗漏应采取全面分析综合治理的原则。 相似文献
25.
以山西省河津市小梁乡为代表,研究了因建筑业的发展壮大而产生的社会经济空心化现象,分析了其形成原因,并提出了解决措施,以期引起大家对这一社会经济现象的关注,开展更深层次的研究。 相似文献
26.
27.
Lean philosophy: implementation in a forging company 总被引:2,自引:2,他引:0
Ajit Kumar Sahoo N. K. Singh Ravi Shankar M. K. Tiwari 《The International Journal of Advanced Manufacturing Technology》2008,36(5-6):451-462
This research addresses the implementation of lean philosophy in a forging company with a focus on radial forging production
flow lines. Here, the prime motive is to evolve and test several strategies to eliminate waste on the shop floor. In this
research, a systematic approach is suggested for the implementation of lean principles. This paper describes an application
of value stream mapping (VSM). Consequently, the present and future states of value stream maps are constructed to improve
the production process by identifying waste and its sources. Furthermore, Taguchi’s method of design of experiments is pursued
here to minimize the forging defects produced due to imperfect operating conditions. A noticeable reduction in set-up time
and work-in-process (WIP) inventory level is substantiated. Finally, we conclude with a discussion of managerial implications
and the future scope of research. 相似文献
28.
Chris Harty 《Building Research & Information》2005,33(6):512-522
An alternative approach to understanding innovation is made using two intersecting ideas. The first is that successful innovation requires consideration of the social and organizational contexts in which it is located. The complex context of construction work is characterized by inter-organizational collaboration, a project-based approach and power distributed amongst collaborating organizations. The second is that innovations can be divided into two modes: 'bounded', where the implications of innovation are restricted within a single, coherent sphere of influence, and 'unbounded', where the effects of implementation spill over beyond this. Bounded innovations are adequately explained within the construction literature. However, less discussed are unbounded innovations, where many firms' collaboration is required for successful implementation, even though many innovations can be considered unbounded within construction's inter-organizational context. It is argued that unbounded innovations require an approach to understand and facilitate the interactions both within a range of actors and between the actors and technological artefacts. The insights from a sociology of technology approach can be applied to the multiplicity of negotiations and alignments that constitute the implementation of unbounded innovation. The utility of concepts from the sociology of technology, including 'system building' and 'heterogeneous engineering', is demonstrated by applying them to an empirical study of an unbounded innovation on a major construction project (the new terminal at Heathrow Airport, London, UK). This study suggests that 'system building' contains outcomes that are not only transformations of practices, processes and systems, but also the potential transformation of technologies themselves. 相似文献
29.
随着VLSI工艺技术的发展和芯片规模的不断增加,尤其是在SOC设计中,原有的那种供电压焊块只能位于芯片边缘的确定益的模式已经不能够满足整个电路性能的需要。在很多情况下,依靠在电源线的拓扑结构确定后的线宽优化,还是无法保证在有限的布线资源下为电路提供可靠的高性能的供电需求。由此,出现了在芯片边缘上浮动放置压焊块及在芯片的顶部放置供电压焊块阵列的方法。文中提出了一种用于SOC设计中新的基于树型结构的浮动压焊块的电源/地线网络优化算法,经过MCNC电路实例测试后得到明显的优化结果。 相似文献
30.
静态EPS及其在建筑工程中的应用 总被引:2,自引:0,他引:2
一级负荷中特别重要的负荷,除由两个电源供电外,尚应增设应急电源。在供电条件比较差的地区,取得第二个电源供给一级负荷有困难时,也需要增设应急备用电源。以往经常用自备柴油发电机组、蓄电池、干电池和镍锦电池应急灯作为应急备用电源。本文通过对目前常用的各种应急电源的分析比较,推荐一种新颖的、静态、无公害、免维护无人值守的、供电质量好、安全可靠的集中供电式EPS装置。 相似文献