动态柔性制造系统仿真平台

针对通常柔性制造系统（FMS）仿真方法在体现制造系统动态变化特性方面的不足，开发了一种FMS的可视化、分布工仿真平台。该平台模拟真实FMS的运行，较好地体现了离散事件动态系统的特性，可以作为调度、控制算法的测试平台。作为示例，在该平台上成功地实现了一种基于遗传算法的FMS动态调度算法，解决了FMS实时运行中各种突发事件下的再调度问题。     

柔性制造系统分布式仿真系统的实现

计算机可视化仿真是对柔性制造系统 ( FMS)进行设计和分析的一种直观而具有实际意义的方法 .利用面向对象方法和离散事件动态系统建模方法 ,设计并实现了一种开放式、可视化 FMS分布式仿真系统 .该系统通过局域网上若干计算机之间的通讯 ,模拟了 FMS自动化生产车间的实时运行状况 ,通过初始化系统数据可得到不同的系统统计结果对 FMS进行分析     

柔性制造系统分布式仿真系统的实现

计算机可视化仿真是对柔性制造系统 (FMS)进行设计和分析的一种直观而具有实际意义的方法 .利用面向对象方法和离散事件动态系统建模方法 ,设计并实现了一种开放式、可视化 FMS分布式仿真系统 .该系统通过局域网上若干计算机之间的通讯 ,模拟了 FMS自动化生产车间的实时运行状况 ,通过初始化系统数据可得到不同的系统统计结果对 FMS进行分析     

基于多Agent的柔性作业车间调度研究

针对多目标柔性作业车间调度问题,构造了基于多Agent的车间调度模型,研究了多Agent之间的交换协调机制．提出一种改进遗传算法并封装在策略Agent中,通过对编码规则、解码算法与交叉、变异算子进行改进,提高了调度优化算法的实用性和优化效果,实现了多目标动态调度,提高了系统的适应性和健壮性．某企业车间应用实例证明其可以满足车间调度高效、稳定的要求．     

半导体晶圆制造系统的时变多目标生产调度优化

从当前半导体晶圆制造企业实际生产调度的角度出发,根据模糊控制理论和模拟退火算法,提出了解决半导体晶圆制造系统(SWFS)时变多目标生产调度复杂问题的方法.大量的仿真实验数据证明,该方法可以在求解速度和优化质量间取得平衡,并实现了全局优化效果,为实现SWFS的科学生产控制与调度提供了有效策略和方法.     

一种异步蚁群算法求解柔性作业车间调度问题

调度问题广泛存在于资源共享型系统中,大多数的调度问题都属于混合整数规划问题.大规模混合整数规划问题是计算科学领域中的NP-hard经典问题之一,一般认为无法用精确计算求解.生产调度是调度的一个重要分支,是实现智能制造关键环节之一.针对多品种变批量柔性作业车间调度问题,以最小制造期为优化目标,设计了一种基于Petri网的异步并行蚁群算法,其中:提出了一种基于Petri网的步可达图构造方法,用于蚁群算法解空间的构造;探讨了传统蚁群算法搜索机制,并给出了一种基于异步仿真时钟的蚁群并行搜索方法;仿真结果表明,多线程控制方法可以有效地避免算法的早熟收敛问题.将所提出的算法应用于某安防件智能制造系统的柔性作业车间调度中,降低了系统的总制造时间,获得较好工程效果的同时验证了算法的有效性.     

全连铸生产调度系统仿真模型的建立

对具有离散事件系统特征的全连铸车间生产调度系统，通过建立其仿真模型进行试验，实现了借助计算机仿真全连铸生产过程，编制了相应调度程序软件，给出多种优化调度方案图，可供实际生产调度参考使用。     

基于遗传算法-多智能体的FMS 工件调度研究

针对柔性制造系统（ FMS）一般调度方法的不足,提出基于全局黑板的多智能体调度系统,该系统建立多智能体交互过程,通过多智能体的合作快速建立调度模型,并通过优化模块对调度模型进行求解,从而获得非劣调度方案。在设计优化模块时,采用遗传算法,针对柔性制造系统调度问题的特点,改进并扩展了基于工序的编码方法,引入工序-机器的关系矩阵,从而实现解和染色体的一一对应关系,并设计算法的适值函数、选择方法、交叉和变异方法。仿真结果表明,该调度系统在求解时收敛速度快、精度较高。最后通过10个经典的柔性job-shop调度算例,与单纯使用遗传算法和禁忌搜索算法进行比较,目标值平均改善2.21％和1.04％。     

基于Petri网和GASA的双资源JSP动态优化调度

以带有控制器的Petri网为建模工具对柔性生产调度中的离散事件建模.该模型不仅能够反映柔性生产线上待加工产品的多条工艺加工路径及其资源约束,还可以对系统的设备维护、各种优先级等特性进行描述.利用遗传算法和模拟退火算法(GASA)获得调度结果,用于解决作业车间在机床、操作工人等生产资源制约条件下的动态优化调度.该调度以生产周期为目标,通过多种交叉、变异、概率更新、再分配策略等遗传和模拟退火操作,得到目标的最优或次优解;尤其重要的是该算法能够在扰动发生后迅速提供新的调度计划.对算法进行了仿真研究,结果表明该算法是可行、有效的.     

集装箱港口集疏运调度系统作业模式的仿真分析

为解决复杂的集装箱港口集疏运系统多阶段动态调度的问题,借鉴柔性制造系统(FMS)生产调度问题的研究方法,提出了由集装箱集疏运问题向FMS生产调度问题转化的方法和模型;分析了各个阶段动态调度的决策点和决策规则,提出了基于规则的方法实现集装箱集疏运系统的实时动态调度,为集装箱码头调度问题的研究提供了新思路和新方法.利用WITNESS仿真工具分别模拟了面向作业线的静态调度和面向作业面的动态调度两种集装箱集疏运调度模式,结果表明,动态调度模式的效率提高了约9.66%.     

Markedness and its Interpretation in Language Use

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.     

Features of Women's language

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.     

低渗透非均质砂岩油藏启动压力梯度研究

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。     

On Tragic Consciousness In The Works By Ernest Hemingway

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.     

Achieving Unusual States of Matter Under High Pressure

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-     

Exchange-Correlation and Electronic Excitation Energies from Pairing Matrix Fluctuations

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-     

Density Functional Theory for the Response of Periodic Systems to Electric Fields Based on the Vector Potential Approach

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     

On the Thermodynamic Limit for Responses to Static Electromagnetic Fields

For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the     

Call for Papers

<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     

Journal of Donghua University ( English Edition) Contents of Volume 31

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