锅具生产中延迟策略的应用研究

大规模定制下的延迟策略已较多的应用于生产系统的运作中。本文着重研究锅具生产中延迟策略的应用,首先通过优化生产工艺,实现半成品及其生产流程通用化：进而定位客户订单分离点（CODP）,提出两个阶段推拉结合的生产计划模式：最后给出了具体实施方法。将以上思路和方法实际应用于Z公司的锅具生产运作,取得了良好绩效。     

面向MC的制造商延迟生产决策优化

以制造商成本最低为目标,建立了制造商分别在不实施延迟生产和实施延迟生产时的成本模型,并运用排队论中M/M/1扩展模型对其总生产成本进行优化。通过仿真及敏感性分析,发现客户单位时间等待成本和定制产品种类数是影响制造商总成本的重要因素。这为制造商正确地选择CODP点位置提供理论支撑,同时为制造商实施延迟策略提供决策依据。     

考虑双目标的JIT生产系统看板数量设定

针对现有JIT系统看板数量决策问题研究多以单目标为主的不足,提出了一种基于实验设计的双目标JIT生产系统看板数量设定方法。该方法同时考虑了高订单满足率和低系统平均在制品水平的双目标优化,以B公司CR油嘴JIT生产系统为例,建立了该JIT生产线的Witness仿真模型以实现数据的收集,以各看板循环回路的看板数量和看板容量进行水平设定,并进行正交实验设计及数据的直观分析处理,然后采用全因子实验的方法,基于帕累托最优的思想获得生产系统看板数量帕累托最优解,形成近似最优看板数量组合的帕累托最优前沿。生产管理人员可根据不同的生产计划和绩效目标从组合中选择合适的看板数量。最后的研究结果验证了该方法的可行性和有效性。     

基于延迟策略的服务型制造系统决策分析

服务型制造作为适合于中国制造业服务化战略实现的先进制造模式,其实施过程如何协调库存、服务和客户参与成为亟需解决的问题。在服务型制造和延迟策略关系分析的基础上,构架了基于延迟策略的服务型制造系统,依据这一系统特征,构建了考虑制造成本和客户价值的多目标规划模型,通过模型厘清了订货数量、服务水平和客户参与度三者之间的内在关系,最后,算例分析验证了模型的科学性与有效性。研究表明:在客户参与情形下,产品模块订货数量在服务型制造系统中独立且可确定,制造成本随订货数量的增加先增后减;服务水平和客户参与度决策取决于管理者对于制造成本和客户价值两者的偏好及参数值大小。     

基于熵权TOPSIS的客户订单分离点定位研究

客户订单分离点(CODP)定位是延迟策略实施过程的中心问题,它直接决定了供应链的精益程度.以CODP定位问题为切入点,分析了CODP上、下游的基本特征,按照功能、成本和提前期,构建了CODP定位决策模型,提出了基于熵权TOPSIS的决策模型的评价方法.最后,以某拉链公司的工艺生产流程为例,验证了该决策模型和模型评价方法的可行性.     

基于客户订单分离点的多级供应控制与延迟制造

探讨了如何用多级供应控制实现供应延迟，分析了将客户订单分离点(CODP)前移到供应商内部流程的优势，探讨了多级供应控制模式下供应商的生产计划问题，最后研究了通过多级供应控制实现供应延迟的产品设计基础——动态物料清单(BOM)。     

客户化供应链中的延迟策略

简单介绍了客户化供应链的概念,描述了延迟策略的内涵。在与客户化供应链整个业务流程结合的基础上,提出了延迟策略可以分为供应延迟、制造延迟、交付延迟和服务延迟,并分别研究了它们的实施目标、实现方式以及运作过程。这四种延迟策略不仅能降低供应链成本．实现产品和服务多样化,而且能够提高供应链的敏捷性,快速响应客户个性化需求。     

交互设计型供应链动态CODP的定位模型及算法研究

与经典MC相比,基于动态CODP的MC,是通过为供应链设置多个CODP,并进行动态调整,实现大规模生产用户定制的产品。它是一种更具优势的供应链系统。其中按照定制形式,可以将其分为选择型供应链与交互设计型供应链。交互设计型供应链由于包含客户自主设计的成分,使得其成为一种更具有一般性与普遍性的生产模式。它的CODP具有产品、设计、生产的三维结构特征,因此定位方式也有了较大的差异。在针对选择型供应链CODP定位研究的基础上,通过分析交互型供应链动态CODP的特征,给出CODP的定位模型,并设计相应的算法。最后以某电动车供应链为例,验证模型及算法的可行性。     

产品族多平台配置问题研究

当前制造业的焦点已经从大规模生产转移到大规模定制,基于平台构架开发和生产产品是实现大规模定制的方法之一.本文提出用多平台方法以最小的综合生产成本为目标生产给定产品族,该方法考虑每一变型产品的需求,以最优的平台数量、每平台最优配置和每平台上生产的变型最优产品组合三者作为决策变量,以混合整形规划方法对问题建模,并描述了模型的最优算法和基于基因算法的演化策略,最后通过一个产品族实例对本文提出的方法进行说明.     

制造企业含折扣的模糊多目标多产品订单优化

针对制造企业中含全单位数量折扣和模糊信息的多产品订单优化问题,构建模糊多目标混合整数规划模型。通过引入不同产品数量区间折扣率变量在可变成本中建立全单位数量折扣分段函数;当配送延迟超过设定界限时,以有效延迟罚金替代以往研究者所提出的罚金无穷大设计并建立具有现实意义的非准时罚金函数。鉴于多产品订单优化的非唯一解属性,引入附加功效函数并计算最优订单分配方案。以重庆某汽车制造商传感器采购案例行了验证,结果表明,该模型可解决折扣策略、模糊信息与解的非唯一性三个特征情景下的多产品订单优化。     

From Industry 4.0 to Research 4.0. Development of High Performance Fibers in the Light of Digitization

We associate a variety of innovations with the term ＂Industry 4.0＂. The pioneer of many 4.0 modifications forms the basisfor the trend towards the integrated di...     

Roman iron and steel: A review

ABSTRACT

The production of ferrous metal increased during the Roman Late Republican period, Principate and Empire. The direct bloomery process was used to extract the metal from its ores using slag-tapping and slag-pit furnaces. The fuel was charcoal and an air blast was introduced by bellows-operated tuyères. Iron formed as a bloom, often as a spongy mass of metal, which contained impurities from the smelting process, including unreacted ore, fuel, slag and fragments from the furnace walls, while the metal was often inhomogeneous with varied carbon contents. Blooms were either smithed directly into bars or ingots or they were broken up, which also allowed the removal of gross impurities and a selection of pieces with similar properties to be made. These could then be forge-welded together and formed into characteristically shaped ingots. Making steel in the furnace seems to have been achieved: it depended on the ore and the furnace and conditions within it. Surface carburization was also carried out. Iron and steel were used extensively in construction and for tools and weapons. Fire welding was often used to add pieces of steel to make the edges of tools and weapons, which could be heat-treated by quenching to harden them.     

Certification Institutions Expected to Update and Transfer Information on Present Standards

Standards are the basis for production enterprises to organize production, ex-factory inspection, trade (delivery) and technical exchanges, product certification, quality arbitration and supervision.……     

The Research of Anti-Wear Properties of Organomolybdenum Compounds in the Engine Oils

A four-ball tester was used to evaluate the anti-wear performance of three kinds of organomolybdemun compounds in the engine oils, i. e., molybdenum dialkyldithiophosphate (MoDDP), molybdenum dialkyldithiocarbamate ( MoDTC), and sulphur and phosphorus freeorganomolybdeum (Molybdate). The results indicate that a low concentration of MoDDP doesn' t improve the anti-wear properties of the commercial engine oils, but a high concentration of MoDDP can obviously improve the anti-wear properties and the load-carrying capacity of the engine oils. MoDTC doesn' t improve the antiwear properties of the engine oils, but worsens the anti-wear properties of the oils. Signifi can timprove ment of frictional and wear characteristics is obtained with Molybdate added in the commercial engine oils and the formulated oils.     

Synthesis of Alumina-Zirconia Nanocomposites by Solgel Process

Al₂O₃-ZrO₂ nanocomposites were developed starting with the solgel process. Composite alumina-zirconia nanopowders were synthesized from metallorganic precursors (Aluminium secondary butoxide and zirconium Iso propoxide) using the solgel process. The parameters affecting the synthesis—solvent, concentration of precursor, R/H ratio (i.e., dilution of water in solvent)—were varied as also the temperature and pH. BET and TEM were used to measure nanosize. Diffuse reflectance spectroscopy and also qualitative optical absorption led to identical particle size estimate. The variation of process parameters was used to study the effect and interdependence of process parameters. Artificial Neural Networks was used to rigorously analyze the process. Although this led to confirmation of interdependence of parameters, the presence of a single overwhelming solvent variable was also established. Then the optimal process was used to synthesize more nanopowder. To produce bulk nanocomposite the nanopowders were sintered by varying the temperature and time period. The sintered lithoids were probed with a vickers hardness tester to measure elastic modulus, hardness, and fracture toughness. The results showed high elastic modulus, modest hardness, and very high fracture toughness.     

Friction Stir Processing Strategies for Uniform Distribution of Reinforcement in a Surface Composite

Friction stir processing (FSP) is an important technique for preparing surface composites. Fabricating defect-free surface composites with uniform particle distribution by FSP is a challenging task. In this study, silicon carbide particles reinforced AA5083 alloy surface composites was fabricated using different FSP strategies including variation in process parameters, dual-tool processing and tool offset overlapping. Material flow of the processed material with reinforcement particles demonstrated that the distribution of particles was influenced by the stirring action of the probe as well as the extrusion of the plasticized material due to the movement of the tool. Process parameters, particularly rotational speed, showed a dominant influence on the distribution of silicon carbide particles.     

Optimum-Simulation von Ernteprozessen

Zusammenfassung Bei der Gestaltung von Ernteprozessen — beispielsweise des Prozesses Mähdrusch, Körnertransport und -abnahme — als transportverbundene Fließarbeitsverfahren mit mindestens zwei verschiedenen Arbeitsmitteln gibt es einen großen Optimierungsspielraum. Solche Prozesse sind mehrstufige Bedienungsprozesse mit gemischter Anordnung der Bedienungseinrichtungen. Außerdem besitzen sie stark ausgeprägte räumliche Aspekte. Es wird vor allem gezeigt, welche Merkmale solcher Prozesse in Simulationsmodellen abgebildet sein müssen, welche Zielgrößen in Abhängigkeit von welchen Einflußgrößen unter Berücksichtigung welcher Prozeßbedingungen ermittelt werden sollten und wie der Bewertungsprozeß zur Ermittlung der gewünschten Informationen gestaltet werden muß.     

Certification Becomes Important for the I Quality; and Safety Supervision of the Chinese Liquor Sector

The end of 2007, over 200 unit products of more than 80 Chinese firms have passed the quality grade certification for liquor products. These products involve distilled spirits, beer, wine, yellow wine, fruit syrup wine and others, and cover over 80% of the national top-branded liquor products.……     

Deposition and Coating Properties on CVD Tungsten

Surface characterization and microstructure studies are performed on chemical vapor deposited (CVD) tungsten coating. There is about 2 μm thickness diffusion layer of tungsten in the molybdenum substrate. The thermal shock test shows tungsten coating has good adhesion with molybdenum substrate, but the elements of oxygen and carbon in the tungsten coating have the bad affection to the adhesion. The result of high-temperature diffusion experiment is the diffusion rate from molybdenum substrate to tungsten coating is faster.     

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