共查询到20条相似文献,搜索用时 995 毫秒
1.
2.
3.
4.
5.
6.
传统的单厂产能规划模式无法适应供应链竞争环境。分析供应链产能规划与传统产能规划模式的区别。基于鼓-缓冲器-绳(DBR)理论的瓶颈思想和协同思想,提出供应链协同产能规划思想,并分别提出供应链瓶颈层和非瓶颈层的产能规划方法,与DBR理论的生产目标相适应,供应链产能规划目标不再单纯考虑成本因素,而是以最大化产出,同时兼顾成本和准时交货为目标。算例结果证明了规划方法的可行性和有效性。 相似文献
7.
拓展了DBR(Drum-Buffer-Rope)理论的应用范围,从传统的生产计划与控制领域延伸到产能规划领域.基于DBR理论的瓶颈思想和协同思想,提出供应链协同产能规划建模思想.在此基础上.提出了基于DBR理论的供应链协同产能规划建模体系框架及模型的运作步骤.以航空发动机供应链为例构建的仿真模型,其运行结果证明了所提出的规划方法的有效性. 相似文献
8.
《液压气动与密封》2017,(5)
该文针对某型液压挖掘机因油缸前腔缓冲造成的机械冲击问题,采用能量法对缓冲压力测试曲线进行分析,确定了冲击产生原因。基于油缸前腔缓冲结构将缓冲过程划分为三个阶段,建立流量方程并对影响缓冲压力变化趋势的主要结构参数进行了分析。依据系统流量与油缸结构建立数学模型计算获得缓冲时间-速度函数,同时建立缓冲结构CFD仿真模型。以缓冲时间-速度函数为输入条件,通过仿真分析重点研究了缓冲套斜面长度、缓冲阻尼孔孔径对缓冲性能的影响,并确定了缓冲结构参数优化值。仿真结果表明:合理缩短缓冲斜面长度并扩大缓冲阻尼孔孔径,可以有效控制缓冲压力曲线变化趋势,满足缓冲峰值压力控制要求的同时降低机械冲击。仿真结果为该型油缸缓冲结构的优化提供了参考。 相似文献
9.
某些高速气动机构在特定的工作环境下,不适合安装复杂、庞大的缓冲装置,要求能够简单、可靠、高效地进行缓冲控制。文中采用了气缸运动行程末端排气节流的方式对气动机构的高速运动进行缓冲控制,并结合机构运动和控制过程建立系统数学模型,在Matlab/Simulink环境下建立系统仿真模型。通过实验和仿真研究,确定了控制参数对机构缓冲效果的影响以及合适的调节范围。 相似文献
10.
11.
Zeming Zou Congxin Li 《The International Journal of Advanced Manufacturing Technology》2006,29(5-6):551-556
When events such as rush orders or machine breakdown occurs during the production process in a job shop, the delivery date
of order may be delayed. To solve this problem, an events-oriented job shop scheduling process is built, and a scheduling
model integrated with an enterprise information system (EIS), including Enterprise Resource Planning (ERP), Product Data Management/Computer
Aided Process Planning (PDM/CAPP), etc., is proposed and analyzed in detail. A genetic algorithm and a hybrid allocation-based
method are used in scheduling. Lastly, an events-oriented job shop scheduling simulation system is presented. 相似文献
12.
Integrated and events-oriented job shop scheduling 总被引:1,自引:0,他引:1
Zeming Zou Congxin Li 《The International Journal of Advanced Manufacturing Technology》2006,29(5):551-556
When events such as rush orders or machine breakdown occurs during the production process in a job shop, the delivery date
of order may be delayed. To solve this problem, an events-oriented job shop scheduling process is built, and a scheduling
model integrated with an enterprise information system (EIS), including Enterprise Resource Planning (ERP), Product Data Management/Computer
Aided Process Planning (PDM/CAPP), etc., is proposed and analyzed in detail. A genetic algorithm and a hybrid allocation-based
method are used in scheduling. Lastly, an events-oriented job shop scheduling simulation system is presented . 相似文献
13.
F.T.S. Chan H.K. Chan A. Kazeroon 《The International Journal of Advanced Manufacturing Technology》2002,20(2):103-113
When examining manufacturing systems using simulation models, different combinations of scheduling rules can be applied to
the models. Each combination satisfies a very limited number of performance measures. The problem now is "how to evaluate these combinations" and "how to reflect the weighting of each performance measure in
the system". Evaluation of scheduling rules is an inevitable task for any scheduler. Only a few evaluation procedures of the
results obtained from computer simulation were found in the literature. In this paper, a framework for the evaluation of combinations
of scheduling rules has been developed using fuzzy multi-criteria decision-making techniques, which are called MAW, Max–Min, and Max–Max. A simulation model is used to illustrate the proposed techniques. The results are compared with a simple approach
for multi-criteria decision-making method, which is called SAW. Results show that MAW is the best technique for obtaining
a high score in the analysis. 相似文献
14.
针对拼焊板零件冲压成形过程中恒压边力方法的不足,提出基于混合H2/H∞理论的变压边力控制方法,建立了变压边力混合H2/H∞控制模型,设计了变压边力混合H2/H∞控制算法和控制逻辑。采用该模型对拼焊板零件冲压成形进行反馈数值模拟,分析有无变压边力混合H2/H∞控制对拼焊板零件成形缺陷的影响,并在变压边力冲压机上进行试验验证。仿真和试验结果表明:基于混合H2/H∞理论的变压边力控制方法可成功冲压出车身前围上盖板,可有效避免恒压边力下的起皱和破裂两种缺陷,该控制方法同时考虑冲压行程和压边板位置进行压边力优化,具有更好的鲁棒性。 相似文献
15.
为预知不同故障情形下的优化重调度方式,实现快速、有效的重调度决策,提出融合调度仿真与改进概率神经网络的重调度方式预测方法。考虑到现场故障样本难获得且无法涵盖全部故障情形,利用仿真实现随机故障下优化重调度样本的生成;以工序加工时间的累计变动、变动任务数、makespan改变量为决策依据,生成各样本的标签;将带标签数据样本输入到概率神经网络模型,实现优化重调度方式预测。实验结果表明:所提出的方法准确率达99.54%;在指定加工车间和生产任务的前提下,故障机序号和故障修复时间对优化重调度方式起决定性作用。 相似文献
16.
F. T. S. Chan H. K. Chan H. C. W. Lau 《The International Journal of Advanced Manufacturing Technology》2002,19(11):830-849
Scheduling of flexible manufacturing systems (FMSs) has been one of the most attractive areas for both researchers and practitioners.
A considerable body of literature has accumulated in this area since the late 1970s when the first batch of papers was published.
A number of approaches have been adopted to schedule FMSs, including simulation techniques and analytical methods. Numerous
articles can be found on each of these approaches. This paper reviews scheduling studies of FMSs which employ simulation techniques
as an analysis tool, since simulation is the most widely used tool for modelling FMSs. Scheduling methodologies are categorised
into simulation of general scheduling studies, multi-criteria scheduling approaches, and artificial intelligence (AI) approaches
in FMSs. Comments on the publications, and suggestions for further research and development are given. 相似文献
17.
用于作业车间调度的模拟退火算法 总被引:4,自引:1,他引:4
作业车间调度问题(Job Shop Schedullng Problem,JSP)是一类NP完全问题,解决此类问题较常使用非数值算法,而模拟退火算法是其中较为突出的而且应用广泛的一种算法。本文结合车间调度问题的特点阐述了模拟退火算法在解决车间调度问题上的应用,提出了基于模拟退火算法的车间调度问题模型,并以Matlab为工具进行了仿真实验。 相似文献
18.
19.
20.
为了解决不确定生产环境下的航空发动机装配调度问题,设计了一种面向航空发动机装配线的知识化制造自适应优化调度算法。算法采用强化学习和过程仿真相结合的调度策略求解方式,以最小化提前期惩罚费用和完工时间成本为调度目标,给出了航空发动机装配的Q学习自适应调度模型;针对装配调度问题定义了四个新的调度规则,定义了航空发动机装配的四个状态特征用于对系统状态进行描述,并针对调度目标设计了合理的回报函数。仿真实验结果表明,在调度过程中,采用提出的Q学习方法在多数情况下都远优于其他规则,尤其在装配任务到达频繁的情况下,总体上表现出更好的优势,显示了良好的自适应性能。 相似文献