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51.
In process-control system design, the Computer Aided Design (CAD) techniques have evolved a new generation of design techniques. This also paves the way for implementing Computer Integrated Manufacturing Systems (CIMS). However, the key issue to accomplishing the objectives in CAD is the automation of conceptual design. This paper first introduces the fundamentals of conceptual design for process-control system design. Then, a strategy to solve the problems in conceptual design is proposed. The associated system configuration and software implementation platform for developing intelligent systems for process control system design are presented. Finally, an application case is studied. 相似文献
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53.
Ilan Gronau 《Information Processing Letters》2007,104(6):205-210
In this work we consider hierarchical clustering algorithms, such as UPGMA, which follow the closest-pair joining scheme. We survey optimal O(n2)-time implementations of such algorithms which use a ‘locally closest’ joining scheme, and specify conditions under which this relaxed joining scheme is equivalent to the original one (i.e. ‘globally closest’). 相似文献
54.
Considerations and strategies behind the design and construction requirements of the Istanbul Strait immersed tunnel 总被引:1,自引:0,他引:1
L.C.F. Ingerslev 《Tunnelling and Underground Space Technology incorporating Trenchless Technology Research》2005,20(6):739-608
This being a design-build project, the challenge faced during preparations of the Employer’s requirements for design and construction of the Istanbul Strait immersed tunnel was to give the contractor as much freedom as possible and yet specify enough so that the Employer obtained the required facility. When completed, this will be a world-class facility. This paper discusses on a strategic level many of the aspects to be presented by the author in two papers in later sessions of the day. Unusual features of this crossing include the deepest ever immersed tunnel crossing, extra waterproofing requirements, strong currents with bi-directional flow, close proximity of the North Anatolian Fault which is predicted to have a major seismic event during the life of the tunnel, and the method of connecting the adjacent bored tunnels to the immersed tunnel. Safety during tunnel construction and operation has been paramount, and resulted in changes to contract packaging and extra requirements. Other challenges discussed include fish migration, control of an international waterway, environmental issues and ensuring the stability of the soft soils during a seismic event. 相似文献
55.
精铸件结构优化设计实践 总被引:1,自引:0,他引:1
黄华龙 《特种铸造及有色合金》2006,26(5):300-302
以6种典型的精密铸件为例,利用“6个千方百计”原则对产品结构进行优化设计,同时辅助有限元分析对优化结果进行再验证。通过减少大平面、避免深长孔、采用加强筋等优化措施,有效地避免了夹砂、鼓包、跑火、缩孔、裂纹等铸造缺陷,实现了少无切削和减轻铸件质量。 相似文献
56.
首先在结构上创造了新型螺栓、螺母和一套崭新的安装机。在主机上去掉了精密、复杂、昂贵的机器人或机械手,改用结构简单的集成齿轮机构,以实现同步旋拧功能;运用现代流体传动与控制的理论,建立流本控制的数学模型和传递函数,从而实现了4个同步安装的效果。 相似文献
57.
本文在已有成果资料的基础上,为组合拱式管桥的设计建立了常规设计表达式,并研制出组合拱式管桥计算机模拟的程序软件CAPBD。该软件具有以下计算功能:(1)计算组合管拱的几何特征参数;(2)计算组合管拱自重和组合拱式管桥的竖向荷载及其材料费用;(3)分析和计算各种载荷作用下组合拱式管桥的内力;(4)组合拱式管桥各控制截面强度校核、稳定性验算以及拱支墩稳定性验算和地基承载力强度校核。 相似文献
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59.
本文介绍了底板翻面机及其液压系统的工作原理和设计特点。该机结构紧凑、运行平稳、工作可靠、能耗低,其成功的设计经验对同类设备的设计改造具有一定的参考价值 相似文献
60.
The complexity of current engineering design demands the collaboration of specialists. Collaboration involves both communication between and coordination among members of a design team. Currently, design collaboration is carried out through the use of schedules, specifications and drawings which only capture the end results of the design process. They fail to record important design information such as the reasoning behind design decisions. In this paper, we describe a tool CADS, that supports collaboration in engineering design. CADS is based on an extension to the Axiomatic Design methodology which not only captures the design elements but also the rationale used to conceive them. CADS serves as a shared database of design information with facilities that support communication and coordination in engineering design.Currently at the Media Laboratory, MIT. 相似文献