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991.
Petri网理论在柔性制造系统(FMS)性能分析中的应用 总被引:1,自引:0,他引:1
本文用 Petri 网的一个子类——时间事件图对流水车间型和作业车间型的柔性制造系统(FMS)建模并进行理论分析,给出了可行排序的判定条件及系统中托盘数量配置与系统生产率的关系,对系统的主要性能指标,如生产周期、工件驻留时间、在制品库存等给出了定量描述.这些结果为系统的设计和运行提供了理论依据. 相似文献
992.
R. Radharamanan 《Computers & Industrial Engineering》1986,11(1-4):209-214
In this paper, the importance of bicharacteristic quality control has been discussed, when it is desired to exercise process control on manufacturing products that present two measurable characteristics which can suffer variations and on the other hand are considered significant for the functioning or the acceptance of the product. The verification that the process is in control or not is made by examining periodically the items of the samples drawn and plotting the points representing the mean of the characteristic in analysis on the corresponding charts. Using the computational program developed, a practical application is carried out for a mechanical manufacturing component that presents two critical characteristics. Also, a programmable mathematical model has been developed, aiming to computationally determine the sample size, and the interval between successive samples, which minimize the expected total cost. Idealized numerical application illustrates the use of the cost model that optimizes these parameters. 相似文献
993.
GE JuHong & XU Jian School of Aerospace Engineering Applied Mechanics Tongji University Shanghai China 《中国科学:信息科学(英文版)》2010,(3)
The bidirectional associative memory (BAM) neural network with four neurons and two delays is considered in the present paper.A linear stability analysis for the trivial equilibrium is firstly employed to provide a possible critical point at which a zero and a pair of pure imaginary eigenvalues occur in the corresponding characteristic equation.A fold-Hopf bifurcation is proved to happen at this critical point by the nonlinear analysis.The coupling strength and the delay are considered as bifurcation parame... 相似文献
994.
Learning-based algorithms in scheduling 总被引:1,自引:1,他引:0
Ewa Dudek-Dyduch 《Journal of Intelligent Manufacturing》2000,11(2):135-143
The aim of the paper is to present a conception of intelligent learning-based algorithms for scheduling. A general knowledge based model of a vast class of discrete deterministic processes is given. The model is a basis for the method of the synthesis of intelligent, learning-based algorithms, that is described in the paper. The designing simulation experiments that use learning is also described. To illustrate the presented ideas, the scheduling algorithm for a special NP-hard problem is given. The significant feature of the problem is that the retooling time depends not only on a pair of jobs to be processed directly one after the other, but also on the subset of jobs already performed. The proof of the NP-hardness of the problem is also given in the paper. 相似文献
995.
绿色制造是现代制造业可持续发展的必由之路,镁合金作为最轻的结构材料其应用将越来越广。本文将绿色制 造理论同镁合金产品的生产相结合,并根据绿色制造要求提出了改进方案。 相似文献
996.
中空纤维膜分离的现状和进展 总被引:2,自引:0,他引:2
中空纤维膜作为一种特种纤维 ,近年来发展迅猛 ,其应用已渗透到各个领域。本文对其近十年的研制和应用进展作了回顾 相似文献
997.
Many modern organizations integrate enterprise resource planning (ERP) and supply chain management (SCM) systems, as they work in a complementary fashion. This often results in technical and organizational challenges. Neway, a Chinese organization, recently went through this complex process. This required efficient procurement and management of hardware, software, and human resources for successful completion. The integrated system was found to improve operations, foster a paperless environment, and provide efficient inventory tracking and picking. It also had several tangible benefits, including reduced lead time and improved inventory accuracy. ERP and SCM systems integration is still a novel concept for a Chinese manufacturing organization. Our case study details the organization's experience, identifies challenges that were faced, and describes solutions adopted to overcome them. 相似文献
998.
In this paper, we present a genetic algorithm for the Flexible Job-shop Scheduling Problem (FJSP). The algorithm integrates different strategies for generating the initial population, selecting the individuals for reproduction and reproducing new individuals. Computational result shows that the integration of more strategies in a genetic framework leads to better results, with respect to other genetic algorithms. Moreover, results are quite comparable to those obtained by the best-known algorithm, based on tabu search. These two results, together with the flexibility of genetic paradigm, prove that genetic algorithms are effective for solving FJSP. 相似文献
999.
1000.
网络化设计和制造信息共享中的STEP和XML技术 总被引:3,自引:0,他引:3
在网络化设计和制造中 ,各个协同工作用户所使用的系统类型具有不确定性 ,随之而产生的一个重要问题 ,就是如何通过互联网来实现异质系统之间的信息集成问题 .本文提出了一种新的理论方法 ,该方法建立在STEP和XML基础上 ,可以使网络化制造中的CAD系统之间、CAM系统之间、以及CAD和CAM系统之间通过互联网实现信息共用 .文章介绍了相关的STEP标准和XML概念 ,以及相对应的EXPRESS和DTD标准 .同时详细介绍如何将STEP和XML作为中性格式模型集成在一起的思路 ,最后 ,提供了一个建立在STEP和XML基础之上的系统框架 相似文献