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951.
基于层次分析法的车炮匹配性评价 总被引:1,自引:0,他引:1
基于层次分析法的车炮匹配性评价体系分为目标层、准则层和方案层.目标层用于确定系统固有综合性能及要求.准则层由若干相关评价因素组成,是同类因素综合形成的评价指标.方案层负责衡量或描述系统特定性能的基本参数.该体系以某型坦克为例,采用和积法进行层次单排序,计算出评价因素的权重向量,以确定准则层对目标层的权重向量. 相似文献
952.
Detailed, high‐resolution numerical simulations have been performed of the buoyancy‐driven motion of deformable, chemically reacting bubble and droplet swarms. Mass transfer rates and chemical reaction selectivities were determined and a comparison is presented between the results for bubble/droplet swarms and single bubbles. The mixing in the wake of bubbles was characterized as well. It was shown that for mixing‐sensitive reaction networks, the hydrodynamics of the bubble swarm may significantly impact the reaction selectivity. Four special cases are highlighted, i.e., highly exothermic reactions, heterogeneously catalyzed reactions, animal cell cultures and experiments. The most important outcome of this work is that bubble swarms and the impact of the swarm hydrodynamics on reacting systems can be studied in detail. This is the first study of this kind reported in the literature. Its importance is paramount as knowledge of the unique flow dynamics inside bubble swarms is crucial to understanding the mechanisms controlling mass transport and chemical reactions and is a prerequisite for effective process intensification. 相似文献
953.
As assembly process planning fulfils the main function of connecting product design to production simulation and thus, the production system itself, a feasible software solution is needed to support this process. Thus, a novel concept is presented that aims at improving the integration of digital product design and assembly planning by introducing a consistent data structuring. This approach helps to reduce redundant tasks and supports the continuous data exchange. It is based on the use of assembly features, i.e. pre-defined geometry elements that contain additional technological information.The prototypical implementation of the concept focuses on the use of commercially available software tools, expanding them with additional functionality for the application of assembly features. The feature-based concept has been tested with a scenario from the automotive supplier industry. For the considered assembly, a comparison between the conventional and the feature-based planning approach is presented in the paper. It points out that the major advantages of the developed concept can be seen in an improved data consistency as well as a higher level of efficiency within the planning activities. 相似文献
954.
近年高速工具钢的发展概况 总被引:12,自引:1,他引:11
概述了高速工具钢钢种、工艺和基础研究的近期发展;并叙述了低合金高速钢、粉末高速钢以及高速钢表面热处理的发展动态。 相似文献
955.
Along with the explosive increase of product data management systems (PDMs),integrating polymorphic PDMs is becoming one of the focuses in the field. Aner brief describing several features of PDM, and market requirements and required performance for integrating the polymorphic PDMs, the paper specializes in discussing some key technologies involved in virtual enterprise oriented integrated development. Some implementing strategies and procedures are proposed. 相似文献
956.
957.
G. Grote S. Weik T. Wfler M. Zlch 《International Journal of Industrial Ergonomics》1995,16(4-6):367-382
A crucial step in any system design concerns the allocation of functions between human and machine. In simultaneous engineering, function allocation is potentially an issue both in product design — if the product is a technical system itself — and in process design. It is argued that well-founded function allocation decisions in relation to the production process are of particular importance in simultaneous engineering as less and less time is allowed for compensation for inadequate or missing decisions which will impede production effectiveness. The focus of recent methods for the allocation of functions is to operationalize the concept of complementarity, meaning to provide guidelines for complementing humans by technical systems instead of replacing them gradually as technical systems become more and more sophisticated. As systems design becomes more complex, involving more and faster changes and placing higher demands on engineers as well as system operators, the idea of complementary gains importance because it stresses the need to allocate functions in a way that supports human control over the production process and the development and maintenance of the necessary skills. Looking at existing methods and instruments for the complementary allocation of functions, one is at first sight confronted with a multitude of criteria for complementarity, but to date neither a fixed set of criteria, comparable to software usability criteria, nor widely accepted methods for their measurement exist. As part of a research project concerned with the development of guidelines whose objective is to assist engineers in designing work systems according to the complementarity principle, four central criteria for complementary function allocation were identified: dynamic coupling, process transparency, human decision authority, and flexibility. These criteria and their application in a design process are illustrated by means of a case study and discussed in terms of other approaches to complementary design as well as their use for simultaneous engineering projects.
Relevance to industry
Adequate allocation of functions between human and machine is crucial for the effectiveness of any production system. With more complex and faster design processes in simultaneous engineering projects, the need for methods supporting prospective analysis and design of human-machine systems has increased even more. The article presents such a method based on the principle of complementarity between human operator and technical system and illustrates its use by means of a case study. 相似文献
958.
徐爱红 《小型微型计算机系统》1995,(10)
本文介绍了利用VAX─11机上修补实用程序PATCH修改映象文件和外部处理程序相结合剖析软件的两种实用有效的方法。一种为将中间信息写入外部文件的静态法,一种为利用父子进程通讯输出中间信息的动态法。 相似文献
960.
Experimental observation of iteration in engineering design 总被引:1,自引:0,他引:1