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1.
在对国内外咽喉道岔通过能力计算方法比较与分析基础上 ,论文提出了车站咽喉通过能力可视化计算集成系统的系统结构和功能设计 ,应用图论和网络优化技术对车站咽喉布置、咽喉及车站作业过程进行抽象建模 ,建立了咽喉作业占用安排网络优化和咽喉作业能力的复合递阶决策模型 .该研究综合运用上述模型、算法、计算机信息处理技术和图形技术 ,可视化模拟咽喉作业情况 ,实现了核心基础数据计算机模拟采集、作业优化安排和最大可实现能力的查定及优化 ,并将结果以图形方式输出 .通过实例验证表明 ,计算结果合理可信 ,可用于车站咽喉能力的评价检验 .  相似文献   

2.
Several industrial problems involve placing objects into a container without overlap, with the goal of minimizing a certain objective function. These problems arise in many industrial fields such as apparel manufacturing, sheet metal layout, shoe manufacturing, VLSI layout, furniture layout, etc., and are known by a variety of names: layout, packing, nesting, loading, placement, marker making, etc. When the 2-dimensional objects to be packed are non-rectangular the problem is known as the nesting problem. The nesting problem is strongly NP-hard. Furthermore, the geometrical aspects of this problem make it really hard to solve in practice. In this paper we describe a Mixed-Integer Programming (MIP) model for the nesting problem based on an earlier proposal of Daniels, Li and Milenkovic, and analyze it computationally. We also introduce a new MIP model for a subproblem arising in the construction of nesting solutions, called the multiple containment problem, and show its potentials in finding improved solutions.  相似文献   

3.
Both analytic and simulation models were used to analyze the capabilities and requirements of an automated circuit card manufacturing system. Analytic models were used to determine the sensitivity of the measures of effectiveness (MOEs) to various design parameters. This analysis gave approximate results and bounded the range of input parameters for the simulation model. A detailed simulation model was required for use during both the design and production phases of the project. This simulation model incorporated only those variables to which the MOEs are most sensitive, and provided additional features to observe system behavior. The benefits and appropriate uses for each class of models are discussed.  相似文献   

4.
This paper presents an approach to simulate and implement by stepwise refinement the whole manufacturing system (MS) by means of distributed simulation. This approach is based on the use of different classes of Petri nets to model different levels of a manufacturing system. Furthermore these classes may match the abstraction levels of a high-level Petri net used to model the MS. Each level can be simulated on a processor or a cluster of processors which can communicate between themselves using a network. The main contribution is to give the opportunity to combine simulation, performance evaluation and emulation. The emulation means that a part of the system can be run in real time while the other part is simulated. Moreover based on the abstraction levels of high-level Petri nets, subsystems can be integrated step-by-step from the design stage to the implementation one, allowing inter-changeability between simulated components and real-time physical systems. This approach is achieved by defining a simulation engine which involves a local simulator, an emulator and an interface to the physical process. Criteria are defined to use an emulator or a local control software for a physical process as a logical process for the conservative distributed simulation.  相似文献   

5.
张健  廖梦洁  齐林 《运筹与管理》2019,28(7):133-143
服务化转型是传统制造企业实现向价值链两端高收益空间演化的重要驱动,却受到转型成本高、转型难度大等多重阻碍。推动制造业服务化政策设置的合理与否,关乎制造企业产业优化升级的成败。本文以由有限理性的寡头与一般企业组成的传统制造集群为研究对象,依据演化博弈理论建立了政府差异化激励条件下集群服务化转型策略的演化博弈模型,利用可视化系统仿真演释了制造集群寡头企业群体与一般企业群体的服务化策略选择过程。研究表明,政策激励设置的合理性直接影响制造集群服务化转型升级的成败,政策制定者应避免陷入无法使制造企业选择服务化策略的政策困境。本文为制造集群服务化激励水平的设定提供了理论依据和解决思路。  相似文献   

6.
This paper puts forward an integrated fuzzy simulation-fuzzy data envelopment analysis (FSFDEA) algorithm to cope with a special case of single-row facility layout problem (SRFLP). Discrete-event-simulation, a powerful tool for analyzing complex and stochastic systems, is employed for modeling different layout formations. Afterwards, a range-adjusted measure (RAM) is used as a data envelopment analysis (DEA) model for ranking the simulation results and finding the optimal layout design. Due to ambiguousness associated with the processing times, fuzzy sets theory is incorporated into the simulation model. Since the results of simulation are in the form of possibility distributions, the DEA model is treated on a fuzzy basis; therefore, a recent possibilistic programming approach is used to convert the fuzzy DEA model to an equivalent crisp one. The proposed FSFDEA algorithm is capable of modeling and optimizing small-sized SRFLP’s in stochastic, uncertain, and non-linear environments. The solution quality is inspected through a real case study in a refrigerator manufacturing company.  相似文献   

7.
Simply because of their rarity, the estimation of the statistics of buffer overflows in well-dimensioned queueing networks via direct simulation is extremely costly. One technique that can be used to reduce this cost is importance sampling, and it has been shown previously that large deviations theory can be used in conjunction with importance sampling to minimize the required simulation time. In this paper, we obtain results on the fast simulation of tandem networks of queues, and derive an analytic solution to the problem of finding an optimal simulation system for a class of tandem networks ofGI/GI/1 queues.Work supported by Australian Telecommunications and Electronics Research Board (ATERB). The authors wish to acknowledge the funding of the activities of the Cooperative Research Centre for Robust and Adaptive Systems by the Australian Commonwealth Government under the Cooperative Research Centres Program.  相似文献   

8.
In this study, two manufacturing systems, a kanban-controlled system and a multi-stage, multi-server production line in a diamond tool production system, are optimized utilizing neural network metamodels (tst_NNM) trained via tabu search (TS) which was developed previously by the authors. The most widely used training algorithm for neural networks has been back propagation which is based on a gradient technique that requires significant computational effort. To deal with the major shortcomings of back propagation (BP) such as the tendency to converge to a local optimal and a slow convergence rate, the TS metaheuristic method is used for the training of artificial neural networks to improve the performance of the metamodelling approach. The metamodels are analysed based on their ability to predict simulation results versus traditional neural network metamodels that have been trained by BP algorithm (bp_NNM). Computational results show that tst_NNM is superior to bp_NNM for both of the manufacturing systems.  相似文献   

9.
制造业产能分享的兴起,改变了传统的制造模式,打破了原有制造业系统的平衡。为研究制造业产能分享参与群体的决策行为,在产能分享平台具有网络外部性、制造企业具有接入成本且博弈群体均具有有限理性的假设条件下,构建了“产能分享平台-制造业产能所有企业-制造业产能需求企业”三个博弈群体的演化博弈模型。运用演化博弈理论分析了模型的演化稳定策略,探讨了制造企业接入成本、产能分享平台的网络外部性系数等对此动态系统稳定性的影响,给出了演化稳定策略的经济和管理意义。最后,用数值仿真对比分析不同参数变化对演化结果的影响,为产能分享平台和制造企业的行为决策提供理论参考依据。  相似文献   

10.
Results are presented of a simulation that mimics an evolutionary learning process for small networks. Special features of these networks include a high recurrency, a transition function which decreases for large input activities, and the absence of tunable weights attached to the lines—the line is either there (weight 1) or absent (weight 0). It is remarkable that these simple systems already exhibit a complex learning behavior and a phenomenon of punctuated equilibrium in the evolutionary process. These findings should be of interest for both, the general understanding of evolutionary dynamics and, more specifically, the understanding of the role of recurrence in combination with nonmonotic response patterns for learning processes. © 2007 Wiley Periodicals, Inc. Complexity, 2008  相似文献   

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