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41.
Multi-criteria decision making for assembly line balancing 总被引:1,自引:0,他引:1
Assembly line balancing often has significant impact on performance of manufacturing systems, and is usually a multiple-objective
problem. Neither an algorithmic nor a procedural assembly line balancing methodology is usually effective in solving these
problems. This article proposes a data envelopment analysis (DEA) approach to solve an assembly line balancing problem. A
computer-aided assembly line balancing tool as Flexible Line Balancing software is used to generate a considerable number
of solutions alternatives as well as to generate quantitative decision-making unit outputs. The quantitative performance measures
were considered in this article. Then DEA was used to solve the multiple-objective assembly line balancing problem. An illustrative
example shows the effectiveness of the proposed methodology. 相似文献
42.
43.
发动机部件强度和刚度评价及疲劳分析 总被引:1,自引:0,他引:1
某汽油机开发阶段须对发动机各主要部件结构强度和刚度做全面评价,并且须考核缸盖缸体的高周疲劳性能.基于STAR-CCM+计算出水套内部气体温度和对流换热系数,将其映射到水套有限元网格表面上作为温度边界条件.得到整个机体的温度场分布以后,在考虑各部件接触非线性的基础上,得到机体各部件的应力和变形等结果并进行评价.在有限元分析结果的基础上考虑材料温度非线性,考察缸体缸盖疲劳安全因数.结果表明,缸盖局部应力偏大,下缸体与油底壳接触面局部间隙过大,缸体缸盖疲劳安全性能满足要求. 相似文献
44.
根据生产线的实际需要,设计并实现了用于生产线的无线信息传输网络节点,研究了系统结构,完成了系统的软硬件设计,详细分析了ZigBee组网通信、应答机制建立等关键技术。测试结果表明,系统传输距离远、可靠性高,能够满足实际应用需要。 相似文献
45.
基于几何推理的装配序列自动规划研究 总被引:2,自引:0,他引:2
文章以问题规约的求解策略,以分解法规划产生的装配序列,提出与或图表达装配体拆卸序列解空间。通过求解拆卸序列与或图的解空间得到装配体的拆卸序列,将拆卸序列反向得到装配序列。为降低装配体拓扑联接图的复杂度,对作业组件做出识别。另外提出了判断零件拆卸性的三个条件,大部分零件无需进行干涉检验,而白逻辑推理即可判断是否满足拆卸条件,避免了多次试凑,具有更高的求解效率,可更广泛地用于装配序列求解。 相似文献
46.
面向装配的CAD技术研究 总被引:1,自引:0,他引:1
面向装配的设计DFA(Design for Assembly)是并行工程的一个有效工具。本文系统阐述了DFA的发展 、意义及其与传统的考虑装配工艺性的区别;介绍DFA的主要内容和几个典型的DFA分析方法,重点分析Boothroyd-Dewhurst方法和步骤;叙述集成CAD技术的DFA应解决的问题及典型的DFA分析软件;最后总结了DFA的研究特点。 相似文献
47.
JI Bo-jing 《数字社区&智能家居》2008,(9)
本文浅谈了Debug在汇编语言程序上机调试中的基本步骤和方法,帮助学生如何利用Debug工具更好地学习汇编语言,对于汇编语言教学具有一定的参考价值。 相似文献
48.
49.
《Ergonomics》2012,55(11):1043-1052
Trunk flexion results in adverse mechanical effects on the spine and is associated with a higher incidence of low back pain. To examine the effects of creep deformation on trunk behaviours, participants were exposed to full trunk flexion in several combinations of exposure duration and external load. Trunk mechanical and neuromuscular behaviours were obtained pre- and post-exposure and during recovery using sudden perturbations. Intrinsic trunk stiffness decreased with increasing flexion duration and in the presence of the external load. Recovery of intrinsic stiffness required more time than the exposure duration and was influenced by exposure duration. Reflexive trunk responses increased immediately following exposure but recovered quickly (~2.5 min). Alterations in reflexive trunk behaviour following creep deformation exposures may not provide adequate compensation to allow for complete recovery of concurrent reductions in intrinsic stiffness, which may increase the risk of injury due to spinal instability. Statement of relevance: An increased risk of low back injury may result from flexion-induced disturbances to trunk behaviours. Such effects, however, appear to depend on the type of flexion exposure, and have implications for the design of work involving trunk flexion. 相似文献
50.
In this paper, sandwich structures for micro-EDM machines are optimized by using parametric study varying composite geometries and parameters like stacking sequence, thickness and rib geometry. The structures are composed of fibre reinforced composites for skin material and resin concrete and PVC foam (Closed cell, Divinycell) for core materials. Column structure was designed by a beam with cruciform rib and performance indices such as static bending stiffness (EI) and specific bending stiffness (EI/ρ) for dynamic stability are examined by controlling the thickness and stacking sequence of composites. For the machine tool bed, which usually has a plate shape, was designed to have high stiffness in two directions at the same time controlling stacking sequence and rib geometry; that is, rib thickness and number of ribs. The sensitivity of design parameters like rib thickness and composite skin thickness was examined and the optimal condition for high stiffness structure was suggested. Finite element analysis was also performed to verify the static and dynamic robustness of the machine structure. L-shaped joint for combining bed and column of the micro-EDM machine was proposed and fabricated using adhesive bonding. The dynamic performance such as damping characteristics was investigated by vibration tests. From the results optimal configuration and materials for high precision micro-EDM machines are proposed. 相似文献