SLP和遗传算法结合在车间设备布局中的应用

用经典的系统布置设计结合遗传算法求解车间设备布局,以高效率获得满意的设计结果,弥补传统SLP设计过程中手工操作的繁琐迭代、易受主观影响、结果不稳定等缺点。并且通过对遗传算法的改进,增强了算法的全局和局部搜索能力。最后,通过实例验证了其有效性。     

三维几何布局的一类启发式求解算法

讨论了一个三维几何布局的复合知识模型ＣＡＬＧ,提出了布局求解顺序规划的启发式规则及相应的布局方案求解策略。该算法有很强的灵活性和柔性。与此同时还讨论了布局求解过程中存在的循环约束、约束不足、鸨噎载及干涉检测等情况的判断及相应处理方法,肖效地支持布局方案的生成。该方法在车身内几何布置设计和机床模块化设计中得到了有效物验证。     

基于NSGA Ⅱ的多目标车间设施布局优化方法

针对多品种批量生产系统,提出了一种基于NSGAII的多目标车间设施布局优化方法。以物料搬运量(或搬运成本)、非物流关系强度、设施所需总面积为优化目标建立了一类多目标优化模型;针对模型设计了一种改进的非支配排序多目标遗传算法;通过案例分析验证了该方法的有效性。     

基于模糊决策与进化算法的生产设备布局优化

为解决复杂情况下制造系统的生产设备布局优化问题,提出了一种将模糊决策与进化算法相结合的设备布局优化方法。进一步完善了优化模型,优化目标包括总成本最小、设备相邻要求最大化和面积利用率最大化等优化目标;其中总成本最小目标考虑了物料搬运成本,设备重置导致的设备拆装、移动成本,生产停工造成的产能损失成本。该方法考虑了用户对于成本、利用率及相邻性要求等存在的满意度、优先度等模糊情况,基于模糊决策理论,对多目标优化模型进行了模糊化处理,设计了模糊适应度函数,用以根据用户的优先关系评价pareto解集。基于求解模型的特点,对多目标进化算法的染色体编码方式与交叉、变异等遗传操作方式进行改进,以提高求解该模型的实用性与效率。最后以实际案例的优化结果证明了该方法的有效性。     

A parallel ordering problem in facilities layout

In this paper, we study a problem that occurs in the row layout of facilities. Among n facilities, suppose that there are t   facilities with some characteristic in common so that they should be arranged along one row, leaving the remainder (n−t$n-t$) facilities to be arranged on a parallel row. The objective is to order the facilities in the two rows such that some cost function is minimized. This problem is called the parallel row ordering problem (PROP). The PROP is a generalization of the single row facility layout problem (SRFLP). Here, a mixed integer programming (MIP) formulation of the PROP is presented which extends a MIP formulation of the SRFLP. We show that a PROP with n facilities may be solved faster than a SRFLP with n facilities. Theoretical and experimental comparisons of the SRFLP and the PROP formulations are presented.     

自动布局布线及验证研究

介绍了在超大规模集成电路版图设计过程中,布局布线时电源、时钟、总线和信号线的布线要点,针对电源的布局设计和时钟网络的设计进行重点讨论;同时讨论了几何设计规则检查、电学设计规则检查和版图/电路图网表匹配检查三种版图验证手段。     

Unidirectional loop network layout by a LP heuristic and design of telecommunications networks

In this paper, we present a new linear programming-based heuristic procedure for optimal design of the unidirectional loop network layout problem. The heuristic procedure employs a linear programming formulation and solves the problem using the flow matrix of the unidirectional loop problem. To find an optimal solution, one can either generate all possible solutions or use a branch-and-bound procedure. But, both above methods require very high computational time and computer memory for larger problems. The heuristic developed in this paper is quite fast and obtains near optimal solutions. The heuristic procedure was tested on 16 different problems selected from the literature. The results showed that in most cases optimal—and in a few cases near optimal—solutions were obtained with very little computational time. Several examples are discussed. We also demonstrate that the above problem formulation and approach can be used to solve a special class of telecommunication networks where a set of computers (or processors) are attached by unidirectional point-to-point links around a loop.     

Topology optimization of stiffened plate/shell structures based on adaptive morphogenesis algorithm

This article proposes an adaptive morphogenesis algorithm to design stiffened plate/shell structures in a growth manner. The idea of this work is inspired by researches in leaf venation which indicates that the adaptive growth of leaf vein provides the relatively large structure with an effective reinforcement. This excellent performance is regarded as the contribution of two primary morphological features: branching and hierarchy. To apply the growth mechanism of leaf venation into stiffened plate/shell structures, a mathematical model describing the growth process is established. Based on this, the adaptive morphogenesis algorithm is developed to make stiffeners “grow” step by step. Besides, the “stiffness transforming operation”, a numerical treatment, is introduced to enable stiffeners to grow along arbitrary directions in the FEM model, which guarantees the design more optimized than previous methods. To obtain a further verification of the proposed method, a comparison between the proposed method and three typical methods is implemented. This comparison shows that the proposed method endows the designed object with a more excellent performance than others. Therefore, the proposed method is competent in the stiffened plate/shell structure design.     

Approaches to uncertainties in facility layout problems: Perspectives at the beginning of the 21<Superscript>st</Superscript> Century

Production uncertainty is one of the most challenging aspects in manufacturing environments in the 21st century. The next generation of intelligent manufacturing is dynamically depending on the production requirements, and success in designing agile facilities is closely related to what extent these requirements are satisfied. This paper presents the most recent advancements in designing robust and flexible facilities under uncertainty. The focus is on exploring the way uncertainty is incorporated in facility design, namely dynamic and stochastic facility layout problems. Recent approaches are explored and categorized in detail, and previous approaches are briefly reviewed in the related categories. Furthermore, research avenues warranting exploration in the emerging field of facility design are also discussed.     

面向结构化布局设计的产品布局多色模型

为实现产品原理方案向结构化布局映射,提出产品布局元层次关系网及产品布局多色模型.首先在布局模块及其属性关系网的基础上构建布局元层次关系网;然后应用多色集合的个人颜色、统一颜色,给出产品布局元层次关系网的数学描述,形成产品布局多色模型,并提出推理算法;再利用个人颜色、统一颜色之间的围道布尔矩阵推理原理,进行产品结构布局设计过程中功能—运动分配—布局模块之间映射过程的形式化描述.应用该模型进行结构化布局设计,可有效地支持产品结构布局设计的公理化;最后在Pro/E平台中利用VC.net 2003工具进行二次开发,并以数控机床结构布局设计为例验证了文中模型和设计方法的可行性和有效性.     

SOSG三维布局搜索树的简化研究

本文首先简要介绍了ＳＯＳＧ三维布局模型的有关概念，然后讨论了基于该模型的布局方案生成算法，着重引入并详细论证了两有关定理，对ＳＯＳＧ三维布局索树进行了简化，最后对简化前后搜索树中终叶节点的数量进行了初步对比分析。     

浅析壮族纹样元素的构成形态在广西本土产品包装设计中的运用

产品包装设计作为企业销售和推广产品的一个重要环节,把代表着广西民族文化的壮族纹样元素融入到包装设计视觉元素中,对发展广西民族区域特色产业起到一定的积极作用。本文通过对壮族纹样元素的形态构成进行分析,并与现代包装版式设计的运用相结合,探寻出具有广西民族文化精神的本土产品包装设计。     

A heuristic approach for transfer lines balancing

The paper deals with optimal balancing transfer lines where the operations in each workstation are grouped into blocks. All operations of the same block are executed simultaneously by one spindle head. Spindle heads of the same workstation are activated sequentially. The workstation time is the sum of the processing times of its blocks. The problem is to find the best assignment of operations to blocks and assignment of blocks to workstations that leads to the minimal transfer line cost (a weighted sum of blocks and workstation numbers). The solution must provide a desired productivity rate (cycle time). It must also satisfy precedence and compatibility constraints. Two heuristic algorithms based on the COMSOAL technique are proposed. Results from computer testing are reported.     

多服务中心设置问题局部搜索算法的分析与实验

讨论了多服务中心设置问题的局部搜索近似算法及其在实际计算中表现出的新性质。首先对局部搜索算法求解多服务中心设置问题的实际近似性能比给出了一个针对性分析结果,然后编程实验对局部搜索求解算法的求解时间和求解质量进行了探讨。     

一种多目标不等面积设施布局问题的启发式算法

多目标不等面积设施布局问题（UA-FLP）是将一些不等面积设施放置在车间内进行布局,要求优化多个目标并满足一定的限制条件。以物料搬运成本最小和非物流关系强度最大来建立生产车间的多目标优化模型,并提出一种启发式算法进行求解。算法采用启发式布局更新策略更新构型,通过结合基于自适应步长梯度法的局部搜索机制和启发式设施变形策略来处理设施之间的干涉性约束。为了得到问题的Pareto最优解集,提出了基于Pareto优化的局部搜索和基于小生境技术的全局优化方法。通过两个典型算例对算法性能进行测试,实验结果表明,所提出的启发式算法是求解多目标UA-FLP的有效方法。