基于eM-Plant的铁水铁路运输物流系统建模与仿真

分析了钢铁厂铁水铁路运输作业工艺流程,采用eM-Plant物流仿真软件建立钢铁厂铁水铁路运输模型,突破了传统铁路运输设备能力的计算思路,将运输过程中的动态因素和概率事件综合考虑到仿真模型之中,获得更为符合实际的计算结果。为钢铁厂改扩建、方案比较、方案优化提供有力支持。     

纤维增强塑料注塑成型集成仿真建模

注射成型过程中的熔体流动分析、纤维断裂和纤维取向预测紧密相关, 并且具有重要的 工程应用价值, 因此对其进行集成仿真是十分有意义的。本文在分析各自特点的基础上, 提出注塑 流动、纤维断裂和纤维取向集成仿真模型, 可对充填和后充填阶段的可压缩流体的非对称流动, 以 及由于熔体流动引起的纤维断裂、三维纤维取向行为进行统一建模, 并且熔体流动和纤维取向相 互耦合。      

基于eM-Plant的生产物流系统仿真与应用

以某制造企业的生产物流系统为例,通过eM-Plant建模仿真,在不同的优化目标下,根据企业实际调整生产物流系统的参数和条件,并对比分析仿真结果,提出了可行的优化措施,为企业生产物流系统最终优化方案的确定提供决策参考。     

基于eM-Plant软件的液压支架装配线物流仿真与优化

以eM-Plant软件为平台,对混流装配线进行仿真建模.在某液压支架项目建成之前,对订单所包含的产品种类、型号规格、需求数量、交货期及物流配送情况进行仿真,并合理优化小车数量、速度和装载量等参数.认为AGV小车为5台,运行速度为1.2m/s,运载量为20件的方案较优.     

基于AMESim的汽车ESP液压系统建模与仿真

汽车电子稳定程序（Electronic Stability Program,ESP）是一种新型的汽车主动安全系统,本文介绍了ESP的系统组成,分析了其工作原理。使用AMESim仿真软件对ESP液压系统进行建模,并设置了有关参数。通过调整不同的液压参数,对仿真结果进行分析,得出各主参数对ESP制动性能的影响关系。模型仿真结果及分析对ESP液压系统设计及参数设置提供了理论参考,并可缩短KSP开发周期。     

基于赋时Petri网的成组生产单元缓冲区建模

以CD造船厂的某成组生产单元为研究对象,在对不同功能和结构的在制品缓冲区进行分类的基础上,建立了该生产单元的扩展赋时库所Petri网模型;将此Petri网映射为eM-Plant软件中的仿真模型,通过对在制品缓冲区库存量仿真数据的监控和分析,讨论了该成组生产单元的瓶颈环节、设备的负荷状况、零件排序调度的优化与否以及生产的连续性和稳定性.     

基于Simio仿真的断路器生产线优化

以温州某电气企业断路器生产线为研究对象,利用工业工程的基础分析方法与Simio仿真,对生产线进行分析与改善.结果显示,工业工程技术与方法的应用,使生产线平衡率从68.04%提高到87.0%,生产节拍从49.40s减少到36.97s,极大地提高了生产线的生产效率,可减少浪费,增加人均产能,提高交货准期率和客户满意率,更好地适应市场需求.     

面向对象仿真建模的研究

本文主要从面向对象的建模和系统仿真建模两个方面对面向对象的系统仿真建模的一般过程进行了论述;使用该建模过程建立了飞控系统领域的系统建模仿真环境。     

基于精益思想的生产线改造仿真与研究

阐述了企业生产线改造过程中精益思想应用的必要性,以及在生产线改造中需要遵循的精益原则:生产线平衡、连续流、产品混流生产和标准化管理。以水洗机为实例,分析了水洗机装配生产线的现状,基于传统思想与精益思想,使用面向对象的eM-Plant软件,建立相应的离散事件仿真模型,以产量、在制品和对市场的反应速度为绩效指标,研究和分析模型仿真进行的输出结果,对两种不同思想的生产线改造进行比较,为装配生产线实际改造提供依据。     

基于仿真的汽车发动机再制造生产线配置优化

以汽车发动机再制造生产线为对象,以设备配置优化和生产线平衡为目标,在分析发动机再制造流程和采集基本工艺数据的基础上,建立了发动机零部件再制造生产线仿真模型;在分析生产线性能数据的基础上,提出改进与优化方案,实现了生产线的平衡,从而以最小的投入满足生产需求.     

NURBS machining and feed rate adjustment for high-speed cutting of complex sculptured surfaces

Owing to the enormous engineering advancement in modern industry, the competition in the development of advanced manufacturing technologies has been increasingly intense as can be seen in automobile, aerospace and various industries. Not only has product quality improved tremendously, but also the demand over production speed has become higher. Therefore, high-speed and high-accuracy production has become a very important goal of modern manufacturing companies. Thanks to ever increasing computer speed and the open architecture of new controllers in computer-controlled machines, the capability and flexibility of today's CNC machines allow us to machine contoured geometry using non-uniform rational B-spline (NURBS) curves directly from the free-form surfaces of a complex CAD/CAM model. As a result, machining accuracy and product quality can be greatly improved while machining time is also significantly reduced. This paper proposes a post-processing approach to convert G1 NC codes from most CAD/CAM systems to NURBS NC paths for highspeed contour machining. The NURBS interpolation strategy that takes into account the optimized cutting feed rate based on machine dynamic response and curvature of the NURBS curve is also developed. Experiments show that the implemented NURBS cutting can significantly improve machining accuracy and reduce cutting time and therefore satisfies the requirements of today's highspeed and-accuracy machining needs.     

小卫星装配建模与仿真的实现

采用基于模板的参数化特征建模方法，基于数据库驱动，主控零件驱动以及系统全关联数据结构的变形设计方法，基于装配规划和动画技术的装配仿真方法，基于多媒体技术和一次开发技术的用户界设计方法，在Pro/ENGINEER环境下实现了小卫星的参数化特征建模、变形设计、零件与装配的联动设计、装配仿真、干涉性检验和用户界面设计等。     

An effective approach to multi-item capacitated dynamic lot-sizing problems

In this study we solve the multi-item capacitated dynamic lot-sizing problem, where each item faces a series of dynamic demands, and in each period multiple items share limited production resources. The objective is to find the optimal production plan so as to minimise the total cost, including production cost, inventory holding cost, and fixed setup cost. We consider both single-level and multi-level cases. In the multi-level case, some items are consumed in order to produce some other items and therefore items face internally generated demand in addition to external demands. We propose a simple three-stage approach that is applicable to both classes of problems. In the first stage we perform preprocessing, which is designed to deal with the difficulty due to the joint setup cost (a fixed cost incurred whenever production occurs in a period). In the second stage we adopt a period-by-period heuristic to construct a feasible solution, and in the final stage we further improve the solution by solving a series of subproblems. Extensive experiments show that the approach exhibits very good performance. We then analyse how the superior performance is achieved. In addition to its performance, one appealing feature of our method is its simplicity and general applicability.     

基于极大熵的单周期产品库存模型

研究具有自由需求分布的单周期问题。建立基本库存模型,给出期望利润表达式,运用极大熵准则确定需求的最可几分布,从而建立单周期产品库存模型,并得出最优订货批量。利用算例将该模型与Scarf订货规则和正态分布假设进行比较。结果表明,基于极大熵准则的库存模型能够获得更多的期望利润。     

A comparison of alternative delivery structures in a dual sourcing environment

This paper studies the flow of material between two vendors and a buyer and develops alternative delivery structures with the intention of minimising total system costs. The proposed delivery structures employ alternative design features and give varying degrees of flexibility to the system as to the emergence of inventory and the allocation of inventory among both stages of the supply chain. The delivery structures are compared in a numerical study and it is shown that an increasing degree of flexibility in the delivery structure always leads to lower total system costs. Further, contextual factors that influence relative performance advantages of the structures are identified.     

飞机装配工序的可视化建模及仿真

针对目前国内外飞机装配工序设计技术研究中存在问题,从新的角度提出基于产品预装配功能自动生成飞机装配工序的方法.通过分析飞机装配工序的组成及特点,建立其数字化模型;利用产品CAD系统中"装配设计"功能开展飞机交互预装配,并从中提取相关装配工序信息,自动生成装配工序;设计和开发算法,将产品装配工序转化为宏指令代码,运行此代码可实现飞机装配过程的动态仿真.结合某飞机垂直尾翼的总装,验证了方法的可行.     

A note on: an optimal batch size for an imperfect production system with quality assurance and rework

In [Ojha, D., Sarker, B.R., and Biswas, P., 2007. An optimal batch size for an imperfect production system with quality assurance and network. International Journal of Production Research, 45 (14), 3191–3214] three models are introduced in the context of imperfect production systems. By analysing the proposed models we identify some problems. In particular we focus on six issues of the models developed in Ojha et al. and propose some modifications. All corrections are presented in detail and the numerical example of Ojha et al. is used to show the influence of the issues addressed in this paper.     

支持操作的装配仿真技术研究

 装配仿真作为一种可视化工具 ,能适时检测和改进产品可装配性 ,是DFA研究的基础关键技术。通过建立装配操作模型 ,实现对装配操作、装配工具、装配夹具等信息的集成 ,并将产品装配环境和装配过程有机地结合在一起 ,实现高层次装配仿真。所提出的算法均已应有于DMAS系统中 ,取得了良好的实际效果。     

Capacitated production and subcontracting in a serial supply chain

This paper extends a series of recent results regarding the polynomial solvability of single and two-echelon deterministic lot sizing models. In particular, we consider a two-echelon supply chain in which production, inventory, transportation, backlogging, and subcontracting decisions are integrated. We allow for arbitrary concave cost functions and for stationary production and subcontracting capacities. We develop dynamic programming algorithms for various problems in this class that run in polynomial time in the planning horizon of the problem.