汽车轴承支架生产线的仿真建模与优化研究

基于Flexsim仿真软件对某精密机械加工公司的汽车轴承支架生产线进行优化改造.首先识别生产线存在的问题,包括产能不足、设备和人员利用率不均衡等,接着建立生产线的仿真模型,有针对性地提出对工序、设备、布局和人员等几方面的仿真优化方案,最后实证研究表明,使用仿真软件进行生产线的优化,可以减少投资,缩短生产周期,是快速实现生产线改造、满足市场需求的有效途径,对提高企业的经济效益有极大的促进作用.     

基于Flexsim的制造车间生产线仿真优化研究

对制造企业生产线优化能有效降低运营成本。某制造生产车间同时生产三种产品,加工设备、生产线复杂。为提高生产效率,采用Flexsim仿真软件建立生产线模型,并通过仿真试验分析现有生产线瓶颈;采用增加加工设备、增加搬运设备及采用柔性生产调度方法等三种方案对生产线进行优化;结果表明,优化后的生产线投入产出率提高了13.83%,车间生产趋于平衡,同时,设备利用率也得到提高。     

基于Flexsim仿真技术在生产线上应用研究

制造企业的生产系统越来越复杂,为了科学地规划与布局生产线,越来越有效的方法是计算机仿真.为此,基于Flexsim仿真软件对浙江某有限公司炼漂车间生产系统进行仿真分析,以发现现有生产系统中的问题,进而对其进行改造,并对改造前后的生产线进行对比分析,得到生产系统仿真优化后的结果.     

基于遗传算法的TFT-LCD冲压生产线布局优化

为提高薄膜场效应晶体管液晶显示器(TFT-LCD)产品的生产效率,基于遗传算法对传统冲压生产线布局进行优化研究.以生产线物流费用最低为目标函数,生产车间总长度、总宽度和设备间保留最小间距等为约束条件,建立了TFT-LCD冲压生产线数学模型,通过编程求得优化解,并根据生产现场实际与自动化改造情况调整出较好布局优化方案.按优化方案进行试生产的测算结果表明,优化布局方案实施效果良好,与优化前布局相比,生产背板周期时间提高了25％,生产线平衡率提高了10％,日产量提高了33.3％,成本降低了25％.     

ATM中仿真数据库技术的研究与实现

封装测试生产线制造环境的复杂程度随着新品种和新设备的增加而增加.数据库技术对仿真系统的建立起决定性的作用.文章详细阐述了在半导体封装测试生产线上仿真数据库的建立方法,仿真软件实现的算法,以及在生产线上的实际应用. 在生产未运行之前预测生产线的生产能力、生产线在不同调度策略下的性能及预见随机故障发生时生产线的调节能力,选一个较好的调度方案来运行生产线.面向对象与多线程技术的运用,使得程序具有很好的可复用性和可扩展性.     

5m精轧机立辊回油管振动的FLUENT软件仿真

分析了宝钢厚板部生产5m宽钢板的精轧机立辊回油管振动情况,建立了管路的数学模型.利用Gambit软件建立回油管的三维模型并划分网格,采用流体动力学计算软件FLUENT对管路进行仿真分析.分析发现,回油管内的空穴和湍流是产生振动和噪声的原因.提出了回油管改造方法并进行了仿真验证,结果表明,改造后的回油管内空穴和湍流现象明显减少,有效地减轻了振动.本文工作对生产线的调试和最终运行提供了理论依据.     

基于人员调度优化的混流生产线平衡改善

针对H企业单头电缆生产线在混流模式下生产线平衡较差的问题进行分析,发现该生产线目前的人力资源调度和配置难以适应作业负荷持续变动的生产现状.因此,以提高生产线平衡率并最小化生产线总人数和最优化各工序人员安排为目标建立数学模型,采用粒子群算法在MATLAB仿真软件中对算例模型进行求解,最终得出的最优人力资源调度方案使得生产...     

价值流在中小型企业生产管理中的应用研究

通过现场的实际观察以及价值流对生产流程的分析,发现企业生产过程中出现生产线平衡率较低、增值时间比较低以及物流路线混乱等问题,利用工业工程方法对生产线平衡率进行改善,利用SLP方法对物流路线混乱以及增值时间比低等问题进行优化.针对价值流的短期性以及静态性的缺陷,提出利用仿真软件对仿真过程进行分析,弥补价值流的缺陷.通过改善,企业的增值时间比以及生产线平衡率都得到较大的改善.提高企业的生产运营能力,降低了企业的生产成本,对我国中小企业发展具有一定的现实意义.     

基于Plant Simulation软件的地铁车辆车体生产产能分析

车体作为车辆的重要组成部分,提高车体产能是工厂日益迫切需要解决的问题.运用Plant Simulation仿真软件建立车体生产线模型,对生产过程进行仿真计算,识别瓶颈工序,提出解决方法.对关键设备的利用率进行计算,进行相应产能优化.结果表明,优化后的车体生产产能可以提升33.33%.     

氨纶生产线模拟仿真系统

由于氨纶生产工艺复杂,生产周期长,原材料价格昂贵,不可能也不允许在生产线上进行操作优化或工艺参数的寻优试验。为此,建立了氨纶生产线模拟仿真系统,并在该模拟仿真系统上进行操作优化、工艺参数的寻优、原料配方、工艺调整等各种试验,取得成功后,在生产线上运行。该模拟仿真系统为企业的操作人员培训、生产设备故障的快速诊断提供了良好的操作平台。     

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     

An affordable accurate evaluation of the binding conformations predicted by molecular docking studies in bio-system

Franck-Condon factors bridge the gap between theoretical modeling and experimental observations for molecular electronic spectroscopy and electron transfer.Under the displaced harmonic oscillator approximation,multidimensional Franck-Condon factors are decomposed into a product of many one-dimensional(1D)Franck-Condon(FC)factors,and each 1D-FC factor is associated with one Huang-Rhys factor that determines the leading contribution of     

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