Implementation of holonic scheduling and control in flow-line manufacturing systems: die-casting case study

The success of a flow-line manufacturing system depends on effective production scheduling and control. However, it has been found that current flow-line manufacturing scheduling and control algorithms lack the flexibility to handle interruptions or resource breakdowns; hence, system performance drops automatically and rapidly when interruptions occur. The objective of this research is to investigate if the performance of a flow-line manufacturing system can be improved by integrating agent-based, holonic scheduling and production control. A holonic manufacturing scheduling model has been developed and implemented into a die-casting manufacturing flow line throughout a simulation model. The analysis takes into account the comparisons of overall performances of the system models with the holonic scheduling and conventional scheduling approaches. Simulation results indicate that the holonic manufacturing scheduling and control can significantly increase the uptime efficiency and the production rate of the flow-line manufacturing system.     

A possibilistic aggregate production planning model for brass casting industry

This article discusses a possibilistic aggregate production planning (APP) model for blending problem in a brass factory; the problem computing optimal amounts of raw materials for the total production of several types of brass in a planning period. The model basically has a multi-blend model formulation in which demand quantities, percentages of the ingredient in some raw materials, cost coefficients, minimum and maximum procurement amounts are all imprecise and have triangular possibility distributions. A mathematical model and a solution algorithm are proposed for solving this model. In the proposed model, the Lai and Hwang's fuzzy ranking concept is relaxed by using ‘Either-or’ constraints. An application of the brass casting APP model to a brass factory demonstrates that the proposed model successfully solves the multi-blend problem for brass casting and determines the optimal raw material purchasing policies.     

基于网络的智能模具制造系统

提出一种基于网络的智能模具制造系统.结合实例描述了其中的信息管理功能、基于知识的工艺设计系统和工艺虚拟仿真系统.描述了模具智能制造系统的实现构架及其建立与实施过程.     

AZ91D合金的挤压铸造工艺及性能

采用直接挤压铸造成形工艺,研究了挤压铸造工艺参数和热处理对AZ91D合金力学性能的影响.研究结果表明:①在浇注温度、挤压压力和保压时间三个工艺参数中,浇注温度对AZ91D合金的影响最大,其次是挤压压力,保压时间的影响最小;②固溶处理在提高AZ91D合金的抗拉强度和硬度的同时提高其延伸率,而固溶时效处理会提高合金的抗拉强度和硬度,但降低其延伸率.     

上限法求解不同型线凹模棒材挤压力

在柱坐标系下,采用上限法推导了不同型线凹模棒材挤压力理论计算公式;并计算了锥模棒材挤压力,其计算结果接近实测值,相对误差平均值为2.5%左右;这表明不同型线凹模棒材挤压力理论计算公式是可行的.     

不确定型AHP在铸造缺陷分析中的应用

本文采用不确定型ＡＨＰ，实现了铸造缺陷的定量分析。该方法明确给出了生产因素对形成缺陷影响的排序，为分析缺陷成因，提供了一种科学手段。生产验证表明，该方法是可行的。     

钢筋压接机承压模的有限元分析

本文讨论了“Ｏ”形钢筋压接机中的一个重要部件承压模的受力分布情况。并对不同厚度的承压模进行了有限元分析，提出了最佳设计方案。     

在冲裁凹模平面固定板上固定镶块的研究

本文对冲裁凹模进行了受力分析，得到了镶块固定的影响因素及力学关系， 以供设计参考.     

浅谈“官本位”与知识分子“过劳死”

近年来,知识分子“过劳死”现象屡见媒体,造成了巨大的社会效应。知识分子“过劳死”现象的产生有其生理、心理、社会性根源,但笔者认为,“过劳死”现象更深层次的是社会文化价值方面的原因。本文试从中国文化的“官本位”思想入手,探索知识分子“过劳死”之根源。     

大跨桥梁悬灌施工组织和设备配套技术研究

结合大跨度桥梁悬臂灌筑法施工实践，研究悬灌施工组织和设备配套的基本技术，通过典型案例分析其应用技术，为合理组织悬灌梁施工提供借鉴经验。