共查询到20条相似文献,搜索用时 78 毫秒
1.
金福江 《华侨大学学报(自然科学版)》2005,26(4):424-427
根据多目标优化的理论,将传统多目标优化的方法与Agent技术相结合,提出一种基于Agent技术的多目标优化分布式智能算法.在该算法中,每个智能体由目标函数、协调算法和通信模块组成.由智能体组成多目标优化的多智能体系统.通过每个Agent的独立优化和Agent之间的通信和协调。实现多目标优化.文中用实例验证算法的有效性. 相似文献
2.
为解决柔性车间调度自动化及优化问题,建立了基于多Agent及遗传算法的柔性车间调度系统。系统是一个由管理Agent,调度Agent及多个加工单元Agent组成,系统中通过遗传算法实现静态优化调度,而通过Agent之间的协作现实动态调度。加工任务到来时,先经管理Agent评估,接受后打包相应信息传递给调度Agent;调度Agent调用其面向对象遗传算法对任务进行优化分解并传递给各加工单元Agent;加工单元Agent根据调度Agent下达的任务进行加工,同时通过相互协调动态调整加工任务,以消除加工过程中出现的不确定性。示例运行表明所建立的系统可行,并兼有实用性,先进性和有效性。 相似文献
3.
《东南大学学报(自然科学版)》2019,(6)
以具有多台自动导引车(AGV)的智能生产车间为对象,以完工时间、AGV数量以及惩罚成本的最小化作为优化目标,构建作业车间多目标调度优化模型.针对多目标调度优化模型的求解需求,提出一种自适应多目标遗传-差分进化算法(AMOGA-DE),采用多段式实数编码的染色体表征调度方案,利用遗传算法获得模型优化解,融合差分进化算法和外部Pareto解集档案构建技术以改进解的质量,引入自适应策略以提高算法的收敛速度,实现多约束条件下AGV系统的多目标调度优化.以一个具有多台AGV的智能制造车间为例进行案例分析,得到调度方案.将AMOGA-DE与NSGA-Ⅱ、SPEA2算法应用于3个不同规模问题,研究结果表明:AMOGA-DE算法具有更快的收敛速度,能得到更好的优化结果,在不同规模的算例上获得了分布均匀且具有较高质量的Pareto解集. 相似文献
4.
研究交货期窗口下的多目标作业车间调度问题.如果任务在交货期窗口内完工,则不受提前/拖期惩罚;如果在交货期窗口外完工,将导致提前/拖期惩罚.设计了基于协同多群体的多目标遗传算法(CMGA),最后将此算法应用于作业车间调度的多目标优化问题,并和其他算法进行了比较.计算结果验证了CMGA在调度方面良好的搜索性能. 相似文献
5.
针对经典Job-shop调度问题的局限性,构建了以加工成本、瓶颈机器负荷、机器总负荷及制造工期为目标函数的柔性作业车间调度多目标优化模型,提出了基于多交叉策略的元胞多目标遗传算法。在分析优化模型的基础上,使用双层编码方式,并采用多个交叉算子协同进化,提出一种多交叉策略的进化算子。针对元胞多目标遗传算法的特点,提出一种改进的精英策略,保证更多的精英个体参与进化,从而提升算法收敛速度。通过2个基准实例求解对比分析,表明所提方法的有效性。将新算法应用于实际生产企业的车间调度问题中,得到了一组Pareto解集,并采用层次分析法得到一种满意度最大的方案。数据结果表明,该算法在解决多目标FJSP的工程有效性。 相似文献
6.
蚁群算法和遗传算法都属于仿生型优化算法,是解决调度问题的强有力的工具。本文针对多目标车间调度问题提出了一种多种群蚁群算法和遗传算法想结合的算法,算法的第一部分用多种群蚁群算法求得各个目标函数的最优解,第二部分把求得的解作为遗传算法的初始种群求得多目标问题的Pareto最优解。仿真结果,该算法有较好的有效性、稳定性和订单适应能力。 相似文献
7.
针对车间动态调度缺乏有效方法的现状.建立了车间动态调度的数学模型.将车间组元定义为多个独立的代理(Agent),并将蚁群在觅食过程中通过释放信息素的方式进行交流与合作的行为,应用到Agent之间的协商与通信中,建立了Agent之间的协作模型,形成了基于多代理协商的动态调度方法.仿真试验对比表明.基于多代理协商的车间动态调度方法优于基于遗传算法的动态调度方法. 相似文献
8.
针对半导体制造车间产品重入机台时存在机台状态不一致,使得传统可重入调度方法难以适用的问题,根据半导体车间生产特性,提出了半导体车间多目标可重入混合流水车间调度问题,以最小化最大完工时间为基础,考虑以降低产品不合格率、减少机台工序切换次数为目标,建立此问题的多目标数学模型.提出基于实质不确定因子的最优觅食算法,采用灰色关联分析与MYCIN不确定因子的勾股模糊集的多目标处理策略,将帕累托(Pareto)解的实质不确定因子作为最优觅食算法的适应度值.编码采用基于工件号编码方案,解码通过三段式方法生成可行的调度解.通过仿真实验和半导体车间案例与其他三种算法对比,验证了所提出的模型,算法性能分析结果表明所提出的模型合理,算法具有明显优势. 相似文献
9.
混合多目标遗传算法在电力系统经济调度中的运用 总被引:2,自引:0,他引:2
针对电力系统经济调度问题的多目标特性,提出了一种混合多目标遗传算法.算法除了改进传统目标函数加权法使之更适于多目标优化问题之外,还利用模糊逻辑技术来自适应调整交叉概率、交叉点位置以及变异概率,使算法具有优良的收敛性能. 相似文献
10.
针对碳达峰、碳中和背景下炼钢-连铸生产调度须要重点考虑的能源约束问题,结合钢铁生产能量流和物质流耦合的特点,在设定工序能源负载约束的基础上,建立了同时追求最大完工时间和总等待时间最小化的多目标生产调度优化模型.然后运用适应度分层进化和先知种群策略改进非支配排序多目标遗传进化算法(NSGA-Ⅱ),基于实际炼钢-连铸生产调度实例的数值计算结果表明:所提多目标优化调度模型能够在能源约束下完成生产调度优化,先验知识和分层进化策略较显著地提升了算法NSGA-Ⅱ的性能. 相似文献
11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness. 相似文献
12.
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly. 相似文献
13.
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well. 相似文献
14.
The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation. 相似文献
15.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。 相似文献
16.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death. 相似文献
17.
Miao Maosheng 《华南师范大学学报(自然科学版)》2014,(6)
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula- 相似文献
18.
Yang Weitao 《华南师范大学学报(自然科学版)》2014,46(6):137-138
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re- 相似文献
19.
Bernard Kirtman 《华南师范大学学报(自然科学版)》2014,(6)
正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that 相似文献
20.
《上海师范大学学报(自然科学版)》2014,(5):550
<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with 相似文献