面向产品族模块化设计和制造的工艺聚类分析方法

为了实现产品族模块化制造,必须综合考虑设计和制造两方面的因素.利用零部件与工艺路线之间的关联,形成了基于聚类分析的产品族模块化设计和制造的方法.通过分析产品族内各成员构成比例及零部件的变形组合,建立了产品族结构模型;在各零部件工艺路线串比较的基础上,构建零部件关联矩阵;采用聚类分析法对零部件进行聚类划分,得到了具有相似工艺路线的零部件聚集;通过分析模块内各零部件对应的各工艺环节任务量的分配比例,实现了与设计模块对应的制造单元的规划.由于考虑了各成员的构成比例,具有对变化的用户订单响应能力.     

面向产品配置的模块划分方法

针对如何快速响应客户需求的问题,对面向产品配置的模块划分问题进行了研究.首先,通过分析客户需求和零部件间的相关性,构建了4个相关性评价准则——客户需求相关性评价准则、功能相关性评价准则、结构相关性评价准则、生命周期相关性评价准则,并提出了4种模块划分调整准则.然后,应用层次分析法确定各准则的权重系数,建立零部件相似性矩阵,并构建零部件模糊聚类树,用模糊聚类方法对零部件进行模块划分.最后,以双梁式桥式起重机桥架为例进行模块划分,验证了该方法的可行性.     

考虑变更传播影响的产品模块分类方法

针对产品变更过程中遇到产品结构复杂及零部件间关联程度强的问题,基于设计结构矩阵,通过模糊聚类分析法,对产品变更模块分层级研究变更传播的特点.首先,将产品零部件按照不同要求划分为不同的模块,将模块作为基本元素,根据模块间的变更依赖关系建立含权重的设计结构矩阵;然后,利用模糊聚类分析法对变更模块聚类,对聚类结果分层级,分析各层级之间的变更传播特点,从而降低模块变更的复杂性,提高模块变更的速度.以某型罐式半挂车为例,对该方法的可行性和合理性进行验证.实验结果表明:该方法能够有效地降低车辆变更复杂性,并能提高车辆工程变更速度.     

基于模块化的拆卸模型及拆卸序列规划研究

为解决拆卸序列规划过程中的组合爆炸问题,提出了产品的基于模块化的拆卸回收模型,对零部件之间的约束关系进行定义;提出了基于约束关系矩阵的拆卸序列规划方法,降低了拆卸模型的复杂度,提高了搜索的效率.最后,通过一个实例验证了该方法的合理性和有效性.     

面向集群制造的注塑机开放式模块化设计技术

通过对集群制造系统结构特点的分析,提出了基于产品技术分割和技术模块价值选择的开放式模块化产品设计方法.该方法运用结构映射这一基于技术的功能和基于设计结构矩阵的技术单元聚类,实现了合理的产品技术分割;通过基于量化设计结构矩阵的技术结果关联分析和技术控制力评价实现了科学的技术模块选择;进而形成了面向集群制造的开放式产品模块化设计方法.最后以我国沿海注塑机企业集群为例,阐述了面向集群制造的开放式产品模块化方法的应用.     

基于产品可装配性评价的CAD-DFA集成系统的研究与实现

为了在产品设计阶段就考虑并解决装配过程中可能存在的问题,确保零部件快速、高效、低成本地进行装配,构建了基于产品可装配性评价的CADDFA集成系统的体系结构,包括装配工艺规划、产品可装配性评价和装配过程仿真等模块·探讨了DFA与各种商用CAD软件的集成方法,对影响产品可装配性的因素进行了详细分析并提出了产品可装配性的模糊评价模型     

机械装配设计的关键技术

讨论了装配设计的两类方法，提出了面向装配设计的四条准则。产品设计时考虑这些装配因素将大大提高产品装配性能和生产效率。提出了装配规划的并行评价准则。探讨了基于装配规划序列分析，面向装配的再设计方法。     

基于结构的加权对齐计算方法

现阶段最优对齐的成本计算大多只与对齐中移动个数保持相关,忽视了活动之间的结构关系,缺乏对单一活动成本的考虑.基于活动的结构关联提出一种增强活动依赖的最优对齐加权计算方法.基于活动的结构关联提出相对权重的概念,并给出计算方法;基于结构出现频次,提出活动权重归一化方法;基于动态规划的对齐方法计算加权后的对齐成本.实验利用一...     

计算机辅助可重组制造系统集成设计框架

为解决目前缺乏能够结合我国制造业现状的具体实施与应用的可重组制造系统计算机辅助系统平台问题,提出了基于面向对象开放式架构、模块化技术方法的可重组制造系统集成设计框架.分析了集成框架的规划问题,给出了体系结构.建立了集成框架的系统功能模块,并就实现每个模块所采用的关键技术进行详细阐述.依据该设计思想,结合某汽车零部件制造企业开发了集工艺分析描述、布局规划、生产调度、仿真优化、成线监控和资源管理为一体的集成系统.     

机械装配设计的关键技术

讨论了装配设计的两类方法，提出了面向装配设计的四条准则。产品设计时考虑这些装配因素将大大提高产品装配性能和生产效率，提出了装配规划的并行价准则。探讨了基于装配规划序列分析，面向装配的再设计方法。     

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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