RECENT DEVELOPMENT OF PROCESS SIMULATION AND ITS APPLICATIONS TO MANUFACTURING PROCESSES

l.IntroductionThemostboortantdrivingforceinmanufacturillistoPrOduCeabetterPrOductatalowercost.GenerallyeffecthemethodsinchideshOrtenintheleadtiminthedesigncyCle,andredUcinthetoolingcostandmaChinedOWnmeatProductionst4e.AllOfthemrewtabettertmderstandingofhO…     

Computer Simulation of Thermal-Mechanical Processing

AlterationIntroductionThereisastrongini6ractionamongtemPetalrefield,strCssfield,andmicrosttuctutulaltOrationinm8terialsduringtheirhotworking[l'2].Especiallyduringthecoolingprocess,inwhichtemPeratorechangnsgreatly,intendionsbecomemorecomplexbecauseoftransformationoccurmnce.Duringthehotdeformation,thingswillaPpearsuchas:a.hotdeformation,relatedtostressfieId,changesessentiallytheshaPeofmaterialsandcausesthevariationofthecontactstatebetWeenthedieandsample,resultinginchangeofthethermalboundnyco…     

对两个重要极限的再认识和应用

许多数学概念，原理、命题、公式等，诸如函数、极限、导数、微分、积分等都反映着客观事物间的普遍联系，都是来源于实践，又作用于实践的，象极限概念就是由于求某些实际问题的精确解答而产生的，两个重要极限limx→0sinx/x和linx→∞（1 1/x)^x也是如此，并不是数学家凭空想象出来的，事实上，许多实际问题归结为这种形式的极限，如几何图形的面化学中元素的化合与分解、生物种群的生长和衰落以及放射性元素的衰变等，讲授两个重要极限时，如果能用一、二个实际问题作引例，并从数学本身说明研究的必要性，使学生了解这种比较奇特的极限的实际背景和理论渊源以及用处，这不仅有利于强化数学知识的应用，解决生产和生活中的实际问题，而且有利于学生对两个重要极限的掌握；不仅有利于形成运用数学知识分析和解决实际问题的能力，特别是形成数学创造能力，而且有利于提高他们学习数学的兴趣和主动性，本文就两个重要极限的教学问题谈点粗浅的看法。     

血清nCa2+含量在肾综合征出血热中的动态变化

目的研究血清离子钙在肾综合征出血热(HFRS)中的变化规律及在发病中的作用。方法用离子选择电极法检测了46例HFRS患者不同病期血清含量，并将与血清尿素氮(BUN)、肌酐(Cr)做相关分析。结果HFRS患者在低血压休克期和多尿期时血清含量降低(P＜0．05)，以少尿期最为显著(P＜0．01)。而且随病情加重，结果依次降低，危重型患者整个多尿期也明显降低。血清含量与BUN、Cr呈负相关(P＜0．01)。结论血清参与发病过程，与病情轻重和肾功状态密切相关。     

A model of household time allocation taking into consideration of hiring domestic helpers

Household maintenance such as childcare not only induces activities and travel but also impose time constraints on individuals’ participation in other activities and travel. Instead of sharing household responsibilities, households may hire domestic helpers for household maintenance. Alternatively, they may get helps from members of the extended family such as parents of household heads. This paper develops a model to analyze households’ trade-offs between hiring domestic helpers for household maintenance and taking these responsibilities by household members. We will apply household economic theories to develop a time allocation model incorporating interactions among household members. We assume that households trade off the money they are willing to spend for hiring helpers with the time they may need to spend for household maintenance activities to maximize utilities, subject to time constraints. The model may be used to analyze the impacts of domestic helpers on household members’ time allocation to subsistence, maintenance and recreation activities. It may also be applied to analyze the impacts of government policies regarding the minimum salary of domestic helpers and the change of household members’ wage rates on households’ decision to hire helpers. The paper extends the current literature on intra-household activity–travel interactions by considering external helps from domestic helpers, which may contribute to the understanding of activity–travel patterns of household members.     

转盘项目在汽车产能扩张中的应用

近年来各汽车公司纷纷扩充产能,转盘项目是保证整车在各地工厂投产的一个重要手段。文章从项目实践经验出发,阐述了构成要素及具体的开展形式,力图为类似扩建项目提供借鉴。     

写作教学课堂层级效应敏感度研究

分级教学中位于中间级别的B级习得者遇到的常见问题是习得者间英语水平参差不齐和未能进入高水平班级的心理低落感,针对这个中间群体,制定合理的教学方案尤为重要。本研究以学习风格匹配辅助下的层级分组教学模式为出发点,探讨写作教学多水平共同提高模式对不同分数人群的敏感性。研究表明,学习风格匹配辅助下的立体分组教学模式有助于B级习得者写作能力整体提高,其效能发挥对于处于中间水平段和较低水平段的群体在一年期末显现,而对较高水平段呈现延时性特征。     

"百船工程"访谈录

又到了洪汛时节.1998年的特大洪灾依然令人胆战心惊,黄水滔滔,千钧一发,百万军民战洪峰.大灾之后提出的有效改善水域环境的"百船工程"目前进展如何?记者为此走访了中国水利投资公司"百船工程"项目办公室王斌副主任.     

价值工程在商业企业选择代理"品牌"中的应用

运用价值工程原理,分析了商业企业选择代理"品牌"要考虑的若干因素,提出了一种优化商业企业选择代理"品牌"种类的价值分析方法,并用实例进行了验证.