基于混合遗传算法的制造/再制造集成物流网络优化设计

为了合理设计制造／再制造混合系统中的集成物流网络结构,综合考虑网络中正向和逆向物流的设施集成与运输整合,建立了一种制造／再制造集成物流网络优化设计的混合整数非线性规划模型,以确定网络中各种设施的数量、位置及规模,并在由此构成的各条物流路径上合理分配物流量,目标是使运营周期内的净收益最大。提出了一种采用自适应交叉和变异操作的混合遗传算法对设计进行优化。最后,通过一个算例验证了所提模型及算法的有效性。     

再制造公差设计优化模型及其应用

为降低再制造产品的成本,保证和提高产品质量,将公差设计方法引入再制造工程。在深入分析再制造公差设计特点和公差分配原则的基础上,提出了一个再制造公差设计的优化数学模型。该模型以统计公差原理为基础,以再制造总成本最低为目标,综合考虑了保证和提高产品性能、表面工程技术、过程能力指数等制约因素,在质量成本中的田口质量损失成本的基础上增加了质量保证成本。结合某企业ZQDR-410型牵引电动机的再制造案例,对传统再制造方案和所提方案进行了比较,证明了该公差设计优化模型的有效性和实用性。     

再制造系统废旧产品回收的最优控制策略

研究了再制造逆向物流系统中废旧产品库存的最优控制问题.为了能够从用户手中回收到合适数量的废旧产品,采用买回废旧产品的方式控制产品的返回强度.通过分析回收过程的特点,提出了一种新的随机库存控制模型,系统的最终目标是求取一个最优的价格策略,以达到有限周期系统总费用的期望值最小.在状态反馈控制规则下,得到了最优费用函数的递归方程,找到了具有两个状态阈值的最优反馈控制策略,并给出了求解最优策略的动态规划算法.最后,通过数值实例验证了算法的可行性,并给出了参数的敏感性分析.     

再制造系统中的计算机支持技术

论述计算机支持技术在再制造产品形成中的应用 ,其中包括面向产品服役环境与可拆卸、可再制造的工程设计技术 ,涂层结合强度、失效机理、优化设计方面有限单元法计算技术 ,容器整体热处理过程的计算机模拟技术等。     

周期盘点库存系统的制造与再制造最优策略

为确定周期盘点库存系统的最优策略,假定制造与再制造的准备次数未知,且计划期的开始对没有用于再制造的旧产品进行处置,把旧产品的处置成本和制造与再制造的变动成本引入目标函数中,构建了有限计划期间更加普遍的总成本模型。利用转换期与制造和再制造周期长度的关系,建立了关于转换期的集合。对于不同的转换期,推导出了相应的最小总成本函数。随后给出一个确定最优策略的简单算法,得到了四种不同条件的最优策略。最后,通过算例说明了相关结论尤其是算法的应用,得到了相应的最优策略和最优总成本。     

制造/再制造混合系统中集成物流网络优化设计模型研究

为提高制造/再制造混合系统中的物流管理绩效,合理设计制造/再制造集成物流网络结构,基于混合整数线性规划方法,提出了一种制造/再制造集成物流网络优化设计模型,据此确定网络中各种设施的数量、位置及物流量分配,以使投资和运营的总成本最小.该模型的特点是：适合单产品、单周期、有能力限制的制造/再制造集成物流网络设施选址-分配问题.考虑了集成物流网络中共用设施的选址;正向物流中统筹考虑再制造产品和新产品的物流分配,但再制造产品和新产品不能相互替代.最后,通过一个算例验证了所提模型的有效性.     

考虑缓冲区库存的退化系统最优维修更换策略

为提高生产过程的连续性,在设备间设置缓冲区,假设上游设备不能修复如新的条件下,以缓冲区库存控制K和设备更换前故障次数N为决策变量,运用几何过程建立了退化系统维修更换模型。以最小化系统运行成本为目标,利用更新过程理论求得系统平均费用率C(N,K),并给出求解最优联合策略的演化算法。借助数值算例演示了本模型,通过灵敏度分析确定了最优策略和相关参数的关系。     

混凝土泵车再制造性评价与信息管理支持系统的设计及应用

针对目前混凝土泵车再制造性评价及再制造设计信息、工艺信息等的管理缺乏实用方法和工具的问题,开发了基于Web的混凝土泵车再制造评价与信息管理支持系统。该系统主要由混凝土泵车再制造成本评估、再制造过程资源环境属性评估和再制造信息管理三个功能模块以及相应的模型库组成。能够从混凝土泵车再制造技术性、经济性、资源环境属性三方面对混凝土泵车再制造性进行分析,并为混凝土泵车再制造提供设计方案、工艺方案等信息的支持,辅助混凝土泵车再制造的实施。通过在某混凝土泵车再制造企业的实际应用,验证了该系统的可行性。     

Optimal performance of networked control systems with bandwidth and coding constraints

The optimal tracking performance of multiple-input multiple-output (MIMO) discrete-time networked control systems with bandwidth and coding constraints is studied in this paper. The optimal tracking performance of networked control system is obtained by using spectral factorization technique and partial fraction. The obtained results demonstrate that the optimal performance is influenced by the directions and locations of the nonminimum phase zeros and unstable poles of the given plant. In addition to that, the characters of the reference signal, encoding, the bandwidth and additive white Gaussian noise (AWGN) of the communication channel are also closely influenced by the optimal tracking performance. Some typical examples are given to illustrate the theoretical results.     

Optimal modified performance of MIMO networked control systems with multi-parameter constraints

The optimal modified performance of the multi-input multi-output (MIMO) networked control systems (NCSs) with encoding–decoding, channel noise in the forward channel and packet dropouts, quantization in the feedback channel is investigated in this paper. A new and efficient tracking performance index for the NCSs is presented which prevents variations in the tracking error where there is no integrator in the plant. The optimal modified performance is obtained by the method of coprime factorization and partial fraction. The results demonstrate that the optimal modified performance is related to the locations of the non-minimum phase (NMP) zeros, unstable poles of the given plant as well as their directions. In addition, the modified factor, packet dropouts probability, channel noise and encoding–decoding are also closely related to optimal modified performance of the NCSs. Finally, we present some particular examples to illustrate the theoretical results.     

Tool management systems

Russian Engineering Research -     

学生收费管理系统

学生收费管理系统是一个典型的信息管理系统,基本开发主要包括后台的数据库的建立和维护以及前端的应用程序的开发两个方面.根据学生收费管理的特点和现状,建立模式,完成了程序的编制工作,进行了程序的整体设计.通过对学生收费管理系统的分析与设计过程的详细描述,贯彻了面向对象的思想和可视化建模的思想,并详细讲解了整个管理的设计过程和基本信息的维护.     

Optimal mass distribution in vibrating systems

The problem of determining the distribution of mass in vibrating systems that optimize the extreme eigenvalue is considered. We give explicit solutions for the fundamental discrete models of an axially vibrating rod and a Bernoulli–Euler beam.The problems are first recast as affine sum of matrices with linear total mass constraint. This formulation allows determination of the eigenvectors corresponding to the optimal eigenvalues by solving a set of quadratic equations recursively. The optimal mass distribution is then determined by the recovered eigenvectors.     

面向不确定性的再制造车间设施动态布局方法

针对再制造工艺过程的不确定性问题,提出一种再制造车间设施动态布局优化方法。对再制造工艺过程的不确定性进行描述,分析了再制造车间的不确定性物流要素,以再制造物流成本和再制造工艺单元重布置成本最小为目标,建立了再制造车间设施动态布局模型,并提出一种基于模拟退火算法的再制造车间设施布局优化求解方法。将所提方法应用到某机床再制造车间设施布局中,运用MATLAB编程实现了再制造车间优化布局,并对再制造布局方案和算法性能做了分析,验证了所提方法的有效性。     

A capacitated production planning problem for closed-loop supply chain with remanufacturing

This paper addresses a dynamic capacitated production planning problem in steel enterprise employing a closed-loop supply chain strategy, in which the remanufacturing process is applied. Particularly, the remanufacturing problem considered in this paper is obviously different from the typical lot-sizing problems, within which all demands are met by production or remanufacturing without backlogs; the production, inventory, and remanufacturing levels all have limits; both the production and remanufacturing setup cost functions are arbitrary and time-varying; the objective is to minimize the total cost. Firstly, the closed-loop supply chain with remanufacturing model is formulated. Then, the genetic algorithm heuristic approaches are proposed to solve the NP-hard problem. Finally, a computational experiment is presented which can solve the 200 size problem efficiently. Furthermore, the comparisons against the branch and bound method show the effectiveness and efficiency of the proposed approach for solving the large size remanufacturing problem.     

Optimal modified tracking performance for MIMO networked control systems with communication constraints

This paper investigates the optimal modified tracking performance of multi-input multi-output (MIMO) networked control systems (NCSs) with packet dropouts and bandwidth constraints. Some explicit expressions are obtained by using co-prime factorization and the spectral decomposition technique. The obtained results show that the optimal modified tracking performance is related to the intrinsic properties of a given plant such as non-minimum phase (NMP) zeros, unstable poles, and their directions. Furthermore, the modified factor, packet dropouts probability and bandwidth also impact the optimal modified tracking performance of the NCSs. The optimal modified tracking performance with channel input power constraint is obtained by searching through all stabilizing two-parameter compensator. Finally, some typical examples are given to illustrate the effectiveness of the theoretical results.     

炼油厂综合库存管理优化问题研究

针对需求不确定条件下的炼油厂各级库存的综合优化问题,以在线连续调和技术为背景,建立了一个系统视角下的全厂库存管理的过程模型。求解时先进行多种产品需求的预测,根据预测值,采用实数编码的遗传算法,在局部优化控制器中以成品油非线性调和属性方程和混炼原油的线性调和属性方程为约束,计算出所需原油和各侧线产出率允许范围内的组分油流速及相应各级库存的优化值。最后,用广义预测控制算法,以局部优化结果为预先设定目标,考虑仿真模型实际运行过程中产生的模型失配、时变和干扰等不确定因素的影响,及时修改模型数据,在线滚动计算全厂库存仿真周期内的综合优化值。     

考虑政府规制和供应链协调的再制造微分博弈模型

现实中企业再制造决策往往受到政府规制和供应链因素的影响,且具有动态变化的特征.为推进再制造供应链的可持续运营,考虑政府规制和供应链协调作用,构建由一个制造商和一个零售商组成的再制造供应链微分博弈模型,分别探讨无政府规制无供应链协调、有政府规制无供应链协调、有政府规制有供应链协调3种情形下新产品和再制品的定价决策及再制造供应链绩效水平.研究发现,政府规制有利于激励制造商积极参与废旧产品的回收再制造活动,而供应链协调契约可以进一步提升消费市场作用并促进政府政策的实施;制造商利用成本分担契约激励零售商进行产品和企业品牌宣传,可有效提高企业商誉水平;在一定条件下,该成本分担契约可以有效实现制造商、零售商和整个供应链系统效益的改进.研究结论对再制造供应链节点间的协调合作以及政府规制政策的制定具有一定的参考价值.