不确定加工时间下装配过程物料配送方法研究

文章针对加工时间不确定导致装配过程物料配送活动无法及时准确进行的问题,在实现装配过程信息实时采集与处理的前提下,提出一种基于实时信息驱动的物料配送模式;在此基础上,提出了物料配送系统,构建了系统的功能体系结构,并对系统实现的关键技术、物料配送动态决策系统进行了研究。将该物料配送方法应用于某发动机装配线物料配送系统,验证了方法的可行性和有效性。     

某摩托车企业发动机装配线物料配送仿真与优化

针对某新建摩托车发动机装配线投产前需验证原生产物料配送方案是否合理的问题,利用Witness仿真平台建立发动机装配线物料配送系统仿真模型,并对其进行仿真分析．发现原方案在装配线边初始存量及配送车辆数量方面均存在不合理之处．据此提出改进方案,并从装配线生产效率、装配线物料缺货率和配送车辆忙闲率等方面进行研究,确定一种最优改进方案,优化装配线边初始存量、调整配送车辆的数量,提高整个物流系统效率和降低企业生产物流成本．     

基于神经网络和知识库的物料配送动态调度

为有效地解决汽车混流装配线中多载量小车物料配送的动态调度问题,提出基于知识库和神经网络的调度方法.首先,对汽车装配线物料配送的动态调度问题进行描述,建立以装配线产量和多载量小车的物料搬运距离作为衡量指标的目标函数.然后通过Plant Simulation软件生成针对汽车混流装配线的仿真数据并对神经网络模型进行离线训练,在实时阶段利用神经网络模型和知识库实现多载量小车最优调度规则的选取.实验结果表明:所提出的调度规则选取方法选择的调度规则大多为最优调度规则,以较低的调度规则计算复杂性确保了调度的实时性能,能够很好地应对动态环境的变化,从而有效提升了多载量小车的动态调度水平.     

飞机制造物料配送技术研究与应用

针对飞机制造物料配送存在的问题,建立支持制造的物料配送任务模型,实现被动配送向主动配送模式转变。研究了物料配送作业流程,并在此基础上介绍了飞机制造物料配送管理信息系统软件功能及实现方案,实现精益敏捷配送。     

混流装配线车间内物料调度工位组划分优化法

基于准时制生产方式(JIT)提出对混流装配线进行工位组划分并安排配送车辆进行配送服务的优化方法.为保证混流装配线生产过程不发生缺料停产的情况,以配送车辆的承载能力与消耗工位配送时间窗为约束,配送车辆满载率与工位物料需求紧急程度为优化目标构建优化模型.运用遗传算法对模型进行求解,优化单个工作日总配送次数及配送车辆数量,给出配送工位组划分及车辆调度方案.最后,实例验证表明该方法具有可行性和有效性.     

考虑转移策略的物料配送和空箱回收集成优化

为了降低飞机移动装配线物料供给成本,构建了考虑转移策略的物料配送和空箱回收集成决策模型并设计了求解算法。在配送和回收任务调度的基础上引入了转移任务和线边物料存放的决策,以最小化小车出行成本为目标建立了数学模型并设计了一种以混沌差分进化算法为框架的双层迭代算法。算法上层对配送物料的分批进行搜索,综合考虑小车装载能力和线边空间约束,通过启发式算法对配送小车的发车时间和线边存储位置进行决策,结合转移小车的线边循环运作方式,设计了修复算子对调度和存储方案进行再优化;算法下层对无法即时装载的空箱组批进行搜索,使用转移调度算法进行解码。通过数值实验验证了该模型和算法的有效性。     

基手RFID的数字化制造车间物料实时配送方法

针对当前数字化制造车间物料配送问题,提出了一种基于射频识别技术的数字化制造车间物料实时优化配送新方法．对数字化制造车间资源进行精确布局,在采用RFID技术对物料配送小车进行实时位置跟踪的基础上,建立数字化制造车间物料配送路径优化模型并采用分支定界算法对模型进行解算,实现配送小车的物料配送路径优化与实时导航;开发了基于RFID的数字化制造车间物料配送系统,验证结果表明：所提出的方法能够有效解决数字化制造车间的物料配送路径优化与实时导航问题,为实现数字化制造车间的准时生产（JIT）奠定了基础．     

基于RFID的数字化制造车间物料实时配送方法

针对当前数字化制造车间物料配送问题,提出了一种基于射频识别技术的数字化制造车间物料实时优化配送新方法.对数字化制造车间资源进行精确布局,在采用RFID技术对物料配送小车进行实时位置跟踪的基础上,建立数字化制造车间物料配送路径优化模型并采用分支定界算法对模型进行解算,实现配送小车的物料配送路径优化与实时导航;开发了基于RFID的数字化制造车间物料配送系统,验证结果表明:所提出的方法能够有效解决数字化制造车间的物料配送路径优化与实时导航问题,为实现数字化制造车间的准时生产(JIT)奠定了基础.     

面向生产车间物料上线的配送时区方法研究

为解决制造企业车间在生产过程中物料上线时间不精准、配送数量不标准、生产效率低下等问题,从物料有效流动的角度,提出了一种结合横向时间维度与纵向数量维度的基于订单为需求信息的时间倒排方法来快速确定车间配送时区。从时间维度与数量维度的角度对车间物料需求进行研究,以时间倒排方法研究车间物料配送时区,通过建立生产排程模型与数学模型来对具体的生产开始时间进行计算,合理安排工作人员对线边物料进行配送,并对生产线边物料进行配送时区的划分,研发出生产车间物料配送系统。以某发动机制造企业生产100台为例,根据生产开始时间以40 min为区间划分出10个配送时区,得出每个时区具体的配送时间,实现精准的配送时间需求点,较好地解决了物料配送时间交接浪费的问题。表明对生产车间线边物料配送实行信息化管理,不但提高了生产效率,同时也有效的支持企业的生产,为后期解决供应商到货时间问题提供参考。     

基于工艺流程的物料配送BOM模型

通过对离散制造环境下,复杂产品装配过程中零部件成套性与产品BOM的分析研究,结合ERP系统中对制造BOM信息的管理和应用,建立基于工艺流程的产品配送BOM模型,作为物料配送的依据,实现装配车间生产计划执行前的零部件成套率控制,并实时记录装配过程的零部件和产品属性信息.     

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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