变质性产品零售商联合采购与运输联盟的稳定性分析

为了降低运作成本,采用合作博弈论对销售变质性产品的零售商联合采购与运输联盟的稳定性展开了分析。在确定性需求下得到了联合采购与运输联盟的最优订货策略。随后,提出了按边际成本进行分摊的规则可使大联盟保持稳定。通过研究发现,零售商进行联合采购与合作运输并不一定能降低联盟的总运作成本。通过数值例子对三种常见的成本分摊规则进行比较,发现在零售商数量较多时,按边际成本进行分摊的方案优势明显。     

基于横向补货的库存协调近似模型

以给定零售商独自拟定订货策略为前提,提出了一种在横向补货允许的情况下,能够有效地刻画系统库存的近似模型.该模型在"最近邻居"优先补货原则下,详细地阐述了系统中的产品需求走势和相应的需求满足率.并通过和仿真试验的数值结果进行比较,验证了该模型的有效性,还对横向补货允许和补货不允许两种不同情况下的系统库存成本进行了比较,形象地给出了横向补货策略在优化库存成本方面的绩效.关于单个零售商订货策略一般性的拓展以及系统联合订货策略的可能性研究也给予了相关说明.     

供应链订货与营销渠道协调的主从对策模型

研究了供应链订货与营销渠道的协调问题,考虑了零售商具有订货成本缩减和营销投资成本,建立了供应链订货与营销渠道协调的Stackelberg主从对策模型.这一模型中,主方零售商具有产品零售价格和投资决策权,从方供应商具有产品批发价格决策权.分析了零售商四种投资策略,针对每种投资策略下的协调模型进行了数值仿真,结果表明在零售商订货成本缩减和营销之间进行投资协调能够同时增加零售商和供应商利润.     

供应商共享POS信息时的信息挖掘策略与方法

提出了在供应链中充分利用共享的部分信息推知未共享信息的思路,建立了供应商充分利用共享的POS信息推测零售商需求预测方法和库存控制策略的模型,通过实例说明了模型的可行性和有效性,并对供应商准确拟合零售商订货策略的价值进行了探讨,提出了供应商利用前馈信息调节零售商订货行为的思路.     

基于质量缺陷和学习效应的易腐品库存与筛选决策问题研究

针对易腐品生产加工及储运环节的不稳定性,以一个生产商与一个零售商组成的二级冷链系统为背景,构建了产品具有随机质量缺陷且变质率服从两参数Weibull分布的冷链库存一体化模型,并兼顾了生产商与零售商固定订货成本存在学习效应时对冷链系统的影响,研究了非100%次品筛选下使得冷链平均总成本期望最小的库存策略与次品筛选策略。最后,结合算例仿真,利用遗传算法,验证了模型的有效性,并在灵敏度分析中发现,原材料变质率、产成品缺陷率以及学习率的增加均会引发系统平均总成本的抬升,且以零售商固定订货成本学习率对冷链成本的影响最为显著。因此,在对冷链库存进行管理时,应更加侧重于对零售终端处固定订货成本学习效应的培育,以便获取更大的成本节约空间,提升冷链整体竞争优势。     

基于协同补货期库存协调模型的扩展研究

在协同预测的库存补充策略和基于协同补给期的一个供应商与一个订货商之间的库存协调策略的研究基础之上,主要研究一个供应商与多个订货商库存协调策略,并与协调之前的库存成本相比,用数值实验的方法证明了合作能够降低供应商与订货商的库存成本,增加效益,给供应链带来了整体效益.     

考虑缺货的两阶段腐败一体化库存—路径模型

在一个生产商给多个零售商配送单一易腐品的供应链中,考虑了一体化库存路径决策问题,并且零售商为了减少库存和运输相关成本而采用缺货损失策略。产品使用同质车辆配送,而在运输及销售过程中产品具有不同的腐败速率(两阶段腐败)。通过构建数学模型以最小化包括生产、配送、腐败、库存、缺货成本在内的供应链总成本。针对供应链库存决策,用数学证明得到函数性质以确定零售商缺货时间、订货周期及生产商的生产周期。针对离散的路径决策,采用固定分区策略对零售商进行分组,在每个分组内采用遗传算法求解对应的运输策略。设计求解算法并编制matlab程序求解问题,结合数值算例和灵敏度分析说明了模型的有效性及相关管理启示。     

第三方物流参与供应商管理库存模型

从供应商管理库存的局限性出发,给出了优化的途径.基于传统的EOQ模型,在充分考虑运输成本和安全库存量的条件下,构建了第三方物流参与的供应商管理库存模型,进一步论证新模型降低了供应商的库存成本和物流成本,增加了供应商和零售商的利润；但随着订货成本的增加,库存和物流相关成本呈上升趋势,供应商和零售商的利润增幅也随之减小.最后通过具体的算例分析来验证上述结论.     

基于协调成本的联合采购参与意愿分析

为了了解两个需求量不同的制造商参与联合采购的意愿,通过寻找他们在不同采购及库存管理政策下的经济订货批量(EOQ)及对应库存相关成本,得出存在协调成本下各制造商愿意进行联合采购的条件.研究结果表明,联合采购及联合库存管理可以降低制造商各自成本,并且需求量小的制造商对联合采购具有更大的热情,同时指出需要进一步完善成本分摊机制.文中对此给出算例进行了说明.     

考虑分组策略的供应链一体化生产-配送模型

研究了供应链中单一生产商对多零售商的协调生产-配送策略问题。生产商配送单一产品给多个异质零售商,为了降低相关成本,根据零售商的订货周期将其分为两组,其中一组零售商的共同订货周期为T,另外一组零售商的订货周期为T/λ,而供应商的生产周期是KT(λ,K均为正整数)。供应链的目标是综合考虑供应商生产成本、配送成本、库存成本以及给所有零售商的补偿成本,并决策K和T以使得总成本最小。通过参数分析构建了两种情况下的一体化生产-配送决策模型,分析给出了其数学性质,得到了理论结果以确定最优决策,并说明了相关管理启示。通过数值对比分析,得出了分组配送策略可以改善供应链绩效的结论,并由此说明了模型的有效性。     

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.     

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.     

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.     

Brainstorming for ISO Strategy 2016-2020

正Responding to ISO’s appeal for survey for the to-be-developed ISO Strategy Plan for 2016-2020,SAC hosted a special workshop over the needs and comments of various fi elds on June 8 in Beijing.The workshop was attended by ISO President-elect and Ansteel General Manager Zhang Xiaogang,SAC Vice-Administrator Yu Xinli,and 30 experts from     

CNAS Passes APLAC's PTP Review

正The review group of Asia Pacific Laboratory Accreditation Cooperation(APLAC)carried out a 4-day peer review of the proficiency testing provider(PTP)for China National Accreditation Service for Conformity Assessment(CNAS)from July 28 to 31,2014.CNAS passed the PTP review with excellent performance.Two senior peer reviewers of APLAC made a comprehensive,rigorous and detailed review of CNAS’s PTP accreditation activities,and made the on-spot inspection of the review groups in Shanghai and Shenzhen respectively.     

新闻(英文)

正China and Greece Sign the Standardization Cooperation Agreement Witnessed by Chinese Premier Li Keqiang and Greek Prime Minister Antonis Samaras,AQSIQ Minister Zhi Shuping and ELOT Chairman and Executive Director Angelos Tolkas signed the SAC-ELOT Standardization Cooperation Agreement.The Agreement is one of the critical cooperation documents signed during Li Keqiang’s visit in Greece,encouraging China and Greece to