具有政府回收约束的闭环供应链回收再制造决策模型

在回收和再制造的闭环供应链中,一个第三方替制造方从用户中买回废旧产品。为了激励废旧产品的回收再制造,政府对制造商设定一个最低回收率,并且对制造商的回收进行奖惩;同时考虑第三方的回收努力,建立了基于第三方负责回收的多级再制造闭环供应链模型,设计了政府与制造商之间的奖惩函数;讨论比较了制造商不回收废旧产品、没有政府奖惩时回收再制造废旧产品和考虑政府约束时回收再制造废旧产品等3种情形下的最优策略,并且分析了参数变化对回收率和供应链成员企业收益的影响;结合国内某家电制造商废旧家电回收再制造的运作情况进行了仿真计算与分析。     

快递包装混合回收闭环供应链决策与协调

目的 优化协调快递包装回收闭环供应链参与者的利益，促使提高废旧包装物回收率。方法 运用博弈论方法，构建由快递包装生产商、快递公司、互联网回收平台和消费者组成的闭环供应链模型，计算和比较在分散决策和集中决策时的利润，引入收益共享契约进行协调。结果 集中决策显著优于分散决策;协调后参与者的利润比协调前的有所提高，利润提高的幅度取决于协调比例大小，数值算例验证了该结果。结论 收益共享契约协调机制能够提高供应链系统利润，激发参与者积极回收快递包装，减轻对环境的污染，实现企业、消费者和社会共赢。建议政府积极推广“互联网+”的混合回收。     

政府奖惩激励下快递包装回收行为演化博弈与仿真分析

目的 厘清快递包装废弃物回收利益主体间的博弈关系与演化路径,解决快递包装回收率普遍较低的问题。方法 在信息不对称和有限理性的条件下,构建政府、回收商和消费者三群体间快递包装回收行为演化博弈模型。分析群体间稳定策略组合的实现条件,运用Matlab软件进行数值仿真,探究不同参数变化对三方演化路径的影响。结果 政府的奖惩力度、激励成本、收益大小是影响博弈三主体策略选择和演化稳定路径走向的关键因素。同时回收商和消费者的参与比例对政府行为选择有显著作用。结论 参与主体得益是影响其行为的关键,政府通过积极鼓励、支持和宣传,同时设立科学合理的奖惩激励政策能够明显提高快递包装回收率。     

有限管制下快递包装逆向物流三方博弈行为分析

我国正逐步推行快递包装回收、垃圾分类等系列举措,但面临着快递包装回收成本高、消费者参与意愿低等一系列矛盾和问题。从演化博弈的视角,构建"电商企业—消费者—政府"三者之间的博弈模型,分析政府管制措施对快递包装回收产业的影响,并以商业软件进行数值仿真分析。研究表明:产业处于发展初期阶段时,政府须保持一定的基础设施投入和财政补贴投入,增加企业实施回收的净收益,如以税收优惠等措施激励电商企业实施逆向物流,同时政府可通过回收计划积分奖励等调动消费者参与积极性;对财政补贴的实施给予适度的监管强度,过高的监管强度会抑制各方快递包装回收积极性,但低监管强度不利于回收产业的市场秩序建立与发展;政府对于不实施逆向物流的电商企业处罚力度大,有助于推动其向实施逆向物流的方向演化;消费者对于电商企业的态度,如不实施逆向物流的不满意度,可影响其市场份额,并促使其开展快递包装逆向物流。     

分类回收条件下闭环供应链的协调问题研究

根据制造商回收的废旧品是否具有可再造性,将废旧品分为可再造废旧品和不可再生废旧品两类,考虑到政府对制造商的激励作用,分别建立了分类回收条件下闭环供应链的集中决策利润模型和分散决策利润模型,并通过两种决策下的最优策略对比,得到了集中决策下闭环供应链系统的效率优于分散决策下的效率的结论。最后,用收益一费用分享契约对分散决策下的闭环供应链进行了协调,并用算例证明了模型的有效性。     

基于微分对策的闭环供应链中制造商合作策略选择

以动态环境为背景，研究了存在第三方的闭环供应链中制造商合作策略选择。分别建立了制造商与回收商和零售商三方共同合作，制造商仅与回收商或零售商其中一方合作，以及三方均不合作等4种合作模型，利用微分对策理论对模型进行求解得到不同合作策略下的最优控制策略。研究发现：制造商总是存在与零售商或回收商合作的动机，制造商与零售商和回收商均合作时供应链利润以及消费者福利最高，制造商与其均不合作时供应链利润和消费者福利最低。但制造商仅与零售商合作时供应链利润是否高于其与回收商合作时的供应链利润依赖于旧产品回收效率和再制造所节约成本等。     

纸张荧光增白剂对色彩复制的影响研究

目的 探究纸张荧光增白剂含量(OBA)对色彩复制的影响,有利于准确测量颜色并实现色彩在不同设备间正确转换,准确复制颜色。方法 选择含较多荧光增白剂、含少量荧光增白剂、不含荧光增白剂3种类型的纸张,分别基于M1/M2的观察条件,测量纸白、CMYK线性色表以及IT8.7/4色表,分析M1/M2观察条件下Δb^*、ΔE^*值以及ICC曲线变化趋势。结果 在M1和M2观察条件下测量纸张基色b^*值的差值绝对值可以确定基材中的OBA的含量,且OBA含量对颜色测量数据的影响与阶调值相关,基本呈负线性关系;在M1观察条件下测量数据生成ICC色彩特性文件,整体线性偏移蓝色,即b^*值往负值线性偏移。结论 基于M1观察条件的色彩管理流程,需进一步研究荧光增白剂含量对b^*值进行线性补偿校正的影响,从而减少纸张荧光增白剂对色彩管理的影响,使纸张上的颜色复制达到理想状态。     

低碳经济下闭环供应链的三方博弈分析

发展低碳循环供应链是实现双碳目标的重要手段，如何从消费端形成低碳循环供应链发展的倒逼机制，是值得研究的问题。考虑碳补贴、碳税、碳交易等政策手段，构建了制造商、零售商和消费者之间的博弈模型，研究了不同策略组合下的均衡条件，并辅以数值仿真分析了内外部因素对博弈系统演化稳定策略的影响。研究发现：当零售商要求的利益回报在合理区间内时，供应链将向理想状态演化；政府部门加大对低碳供应链的补贴力度和对高碳供应链的处罚力度有助于供应链向低碳方向演化；政府的低碳政策存在一定的互补性，可适当提高碳税以降低财政支出；制造商应给予消费者一定的废旧物回收收益，以刺激消费者积极参与低碳循环供应链的建设。     

考虑渠道权力结构和产品双重差异的再制造闭环供应链最优定价决策

针对具有不同渠道权力结构和回收拆解产品质量差异、新产品与再制造产品价格差异的再制造闭环供应链,主要研究其成员企业最优定价决策问题。构建了包含制造/再制造商、零售商、消费者和回收拆解商的三级再制造闭环供应链决策模型;采用Stackelberg主从博弈确定不同渠道权力结构下各成员企业的最优定价策略及其利润,并重点探讨废旧产品回收率τ、产品替代系数δ两个关键参数对它们的影响;将该决策模型应用到汽车发电机再制造闭环供应链案例。研究结果表明：1） 对于3种渠道权力结构,当制造/再制造商和零售商为主导者时,其自身利润和再制造闭环供应链总利润均最大;而当回收拆解商为主导者时,其自身利润和总利润却最小;2） 随着τ和δ的提高,单位新产品与再制造产品的最优批发价、最优零售价均增加,单位废旧产品的最优回收价则降低;制造/再制造商和零售商的利润下降,回收拆解商的利润上升,导致再制造闭环供应链的总利润呈U形。研究能够为各成员企业的最优定价决策提供有效支持与参考。     

电子废弃物双元回收闭环供应链定价决策研究

考虑生产者责任制对于“无废城市”可持续发展的重要性,从逆向供应链视角,引入制造商和消费者,构建环卫企业和回收企业并行的双元回收闭环供应链模型,通过深入分析多元主体各自在供应链经济活动中的最优决策及其对供应链整体所产生的影响,验证模型的合理性。研究结果表明：消费者的价格敏感度对回收量具有显著影响;回收主体之间的竞争状态影响着供应链的健康持续运行;制造商的定价决策对供应链各主体的策略选择产生不同程度的影响。     

Insertion of triangulated surfaces into a meccano tetrahedral discretization by means of mesh refinement and optimization procedures

In this paper, we present a new method for inserting several triangulated surfaces into an existing tetrahedral mesh generated by the meccano method. The result is a conformal mesh where each inserted surface is approximated by a set of faces of the final tetrahedral mesh. First, the tetrahedral mesh is refined around the inserted surfaces to capture their geometric features. Second, each immersed surface is approximated by a set of faces from the tetrahedral mesh. Third, following a novel approach, the nodes of the approximated surfaces are mapped to the corresponding immersed surface. Fourth, we untangle and smooth the mesh by optimizing a regularized shape distortion measure for tetrahedral elements in which we move all the nodes of the mesh, restricting the movement of the edge and surface nodes along the corresponding entity they belong to. The refining process allows approximating the immersed surface for any initial meccano tetrahedral mesh. Moreover, the proposed projection method avoids computational expensive geometric projections. Finally, the applied simultaneous untangling and smoothing process delivers a high‐quality mesh and ensures that the immersed surfaces are interpolated. Several examples are presented to assess the properties of the proposed method.     

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.……     

Flow calorimeter for enthalpy increment measurements on condensed gases

A flow calorimeter for enthalpy increment measurements on condensed gases is presented. A better knowledge of the properties of the liquefied natural gas is needed, and therefore a liquid loop has been designed for our flow calorimeter. The fluid loop in the calorimeter is designed in order to avoid the two-phase region, since two phases would give compositional disturbances in the measurements. The avoidance of the two-phase region is made possible by increasing the pressure of the test fluid after the measurement section, then heating the fluid at super-critical pressure past the critical point. Finally, the fluid is throttled to the low-pressure gas state at the inlet condition of the compressor that circulates the fluid. To perform the pressure increase, a new cryogenic pump has been designed. To evaluate the new equipment, measurements were taken on liquid ethane over the temperature range 146–256 K at pressure between 0.9 and 5.1 MPa.     

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...     

Refrigerators Enter a New Era of Health Preservation Frestech initiates the establishment of China's first standard for household sterilization refrigerators

On November 30, 2007, the China Association for Standardization (CAS) held a press conference at Beijing Diaoyutai State Guest House. Leaders from the China Household Electric Appliance Research Institute, the China Household Electric Appliance Association, and the China Consumers' Association attended and made speeches.……     

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.     

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.     

A study of centrifugal cast high boron high speed steel

In the present study a high‐boron high speed steel (HSS) roll material was designed. Many expensive alloy elements have been substituted by cheap boron alloy, and high‐boron high speed steel roll has been manufactured by centrifugal casting method. The microstructures, mechanical properties and wear resistance of centrifugal casting high‐boron high speed steel roll have been investigated by optical microscopy (OM), scanning electron microscopy (SEM), and X‐ray diffraction (XRD) analysis, hardness test, impact test and wear test. The results indicated that the solidification microstructures of high‐boron high speed steel roll consisted of M₂(B,C), (W,Mo)₂(B,C), M₃(B,C), M₂₃(B,C)₆ type borocarbides and martensite, a small amount of retained austenite. Borocarbides were continuously distributed over the grain boundary. After quenching from 1050 °C, local broken network appeared in partial borocarbides, and fine secondary borocarbide precipitated from the matrix. After tempering from 525 °C, the amount of precipitated borocarbide increased significantly. After heat treatment, the hardness of high‐boron high speed steel roll excelled 60 HRC, and its impact toughness excelled 8.0 J/cm². The single groove steel rolling amount of high‐boron high speed steel rolls increases by 500% than that of bainite cast iron roll, when the rolls are used in K₁ mill housing of bar mill.     

Thixotropy of Systems with Shear Thinning and Plastic Flow Behavior

The definition of the thixotropy is a decrease in viscosity with time in shear and a subsequent recovery of viscosity after the shear deformation is removed.We ...