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41.
Udayan Nandkeolyar David P. Christy 《International Journal of Flexible Manufacturing Systems》1992,4(3-4):267-292
Evaluating the design of flexible manufacturing systems is complex. Developing a measure of performance useful for evaluating alternate designs continues to be interesting. Here, total productivity of the system is proposed as an appropriate measure. Specification of parameters based upon strategic considerations for this measure are discussed. Finally, the usefulness of the measure is demonstrated through an example. 相似文献
42.
One of the main problems faced while configuring or reconfiguring manufacturing systems is to rank alternative designs taking into account all the different aspects involved (both tangible and intangible). For this purpose the Analytic Hierarchy Process (AHP) is a well-known decision making support method that addresses this problem. A major drawback of AHP is that uncertainty in the judgments of the decision makers and the resulting impact on the ranking is not considered. In real situations, however, judgments based on perceived future scenarios are almost always uncertain. To solve this problem in this paper we present the first complete probabilistic extension to the AHP method. The new method provides the decision maker not only with information on the ranking of the alternatives but also the probability that the ranking remains stable even in presence of uncertainty in the judgements. We verified the validity of the new method in a real application developed for the Ferrari racing team. 相似文献
43.
我国制造业企业信息化现状分析 总被引:5,自引:0,他引:5
杭建平 《北京机械工业学院学报》2002,17(2):33-37
制造企业实现信息化可以提高企业的核心竞争力和经济效益。但就目前而言,我国制造业企业信息化工作的整体水平还处于较低的层次,实践中仍存在一些问题,制约了企业信息化的进程。对我国制造业企业信息化的现状进行了分析,详细剖析了制造业企业在实施企业信息化工作中出现的一些典型误区,并提出企业领导人必须不断提高信息化意识,统筹安排企业信息化工作,从各个方面入手,有层次地逐步实施信息化,才能顺利地实现企业信息化的目标。 相似文献
44.
成组技术和造船模式的发展 总被引:3,自引:1,他引:2
本文论述了GT是造船模式进步的思想基础,并阐明了GT在SCIMS中的作用. 相似文献
45.
Recently, efficient scheduling algorithms based on Lagrangian relaxation have been proposed for scheduling parallel machine
systems and job shops. In this article, we develop real-world extensions to these scheduling methods. In the first part of
the paper, we consider the problem of scheduling single operation jobs on parallel identical machines and extend the methodology
to handle multiple classes of jobs, taking into account setup times and setup costs. The proposed methodology uses Lagrangian
relaxation and simulated annealing in a hybrid framework. In the second part of the paper, we consider a Lagrangian relaxation
based method for scheduling job shops and extend it to obtain a scheduling methodology for a real-world flexible manufacturing
system with centralized material handling.
This research was supported in part by the Office of Naval Research and the Department of Science and Technology grant N00014-93-1017. 相似文献
46.
Machining process planning involves the formation of a set of directions describing the machining operations required to transform raw stock into a finished part. Conventional process planning, performed manually, relies on the knowledge and competence of an experienced process planner and tends to be time consuming and error prone. In the past two decades, much effort has been spent on improving process planning by utilizing the power of a computer to emulate the capabilities of an experienced planner. During the same period, computer-aided design (CAD) and computer-aided manufacturing (CAM) software has been developed to enhance design productivity and to assist the NC code generation facets of the machining process. The entire planning process may be automated be integrating CAD and CAM using computer-aided process planing (CAPP). The research described in this paper outlines the design and development of an intelligent CAPP system integrating two commercial CAD and CAM software packages, Autocad and Mastercam. 相似文献
47.
48.
本文分析了分布式制造动态调度的本质,提出了对分布式制造资源集成系统的要求,并利用多A-gent理论对分布式制造资源集成系统进行建模,给出了系统集成的拓扑图和说明系统的信息流动过程,解决了构造分布式制造动态调度资源集成系统的理论基础。 相似文献
49.
A hybrid PC/PLC architecture for manufacturing-system control—theory and implementation 总被引:1,自引:0,他引:1
A. Ramirez-Serrano S. C. Zhu S. K. H. Chan S. S. W. Chan M. Ficocelli B. Benhabib 《Journal of Intelligent Manufacturing》2002,13(4):261-281
This paper presents a novel and generic PC/PLC-based software/hardware architecture for the control of flexible manufacturing workcells. The proposed implementation methodology is based on the utilization of any one of the available formal discrete-event-system control theories in conjunction with state-of-the-art industrial programmable-logic controllers (PLCs). The methodology has been illustrated to be a viable technique through its actual implementation in our laboratory using a robotic-workcell testbed. The specific control theory used is a combination of Extended Moore Automata and Ramadge-Wonham Automata that has been developed by our research group. The modular control software architecture has been developed for MS-Windows environments (running on one PC interfaced to the PLCs) and allows the use of different formal control theories as well as different commercial PLC hardware. The effective graphical user interface provides a transparent programming environment, where users are not expected to have a full knowledge of the formal control theory used. 相似文献
50.
展望21世纪的制造业及相关技术 总被引:1,自引:0,他引:1
综述了制造业未来的发展前景,重点分析了与制造业相关的制造系统、机械加工技术、生产组织形式、人员素质的发展趋势。 相似文献