Primary Structural and Quantitative Analysis of Infeasible Solution to Job shop Scheduling Problem

1　IntroductionTheJobShopSchedulingProblemisawell-knownNP-hardproblem,whichattractslotsofmathematiciansallovertheworldspendingmuchtimeandenergyinthisfield.Uptonowtherearemanyefficientheuristicalgorithms,whichhadalreadybeendeveloped,buttheinfeasiblesolutioncertainlypossessesthemajorityofsearchspacewhichhasinfluencedtheefficiencyofthesealgorithms.Atthemoment,noonehasbeenfoundtobededicatingtothequantitativeanalysisoftheinfeasiblesolutionproblem.InthispaperthestructureofinfeasiblesolutiontoJSS…     

The Optimum Model and Its Decision Support System of Coal Quality Balance

1　 Coal Quality Balance and Its Significance[1]Coal quality balance is to make a comprehensive plan concerning excavation steps and coalamount disposition of different coal seams based upon the natural coal-preservation stateand its relation with mining engineering in the three dimensional space so as to have thequality of coal excavated from different districts blended and coordinated the greatestextent possible and ensure the coal quality uniformity and stability,thus raise economicand soc…     

多次走刀时端铣加工优化对策的研究(英文)

以最大生产率和最低成本为目标并考虑各种实际约束，采用详细地优化分析和搜索法相结合的途径。叙述了多次走刀时面铣加工的优化对策。这种优化途径不但能保证全局优化，还能大大减少计算机处理时间，从而使优化对策更为适用。最后的数值模拟研究证实了该优化对策及其相应ＣＡＭ软件的正确性、实用性和优越性     

Robust H_∞ Control of Robot Manipulator

１ＩｎｔｒｏｄｕｃｔｉｏｎＡｓｗｅｋｎｏｗ，ｂｅｃａｕｓｅｏｆｅｎｖｉｒｏｎｍｅｎｔａｌｃｏｎｄｉｔｉｏｎｓａｎｄｓｐｅｃｉａｌｄｅｓｉｇｎｄｅｍａｎｄｓ，ｒｏ－ｂｕｓｔｎｅｓｓｆｏｒｒｏｂｏｔｃｏｎｔｒｏｌｂｅｃｏｍｅｍｏｒｅａｎｄｍｏｒｅｉｍｐｏ...     

实时控制计算微分代数系统的代数约束算法

本文结合实际的航天工程背景，针对飞行器轨道约束实时控制模型问题进行了算法研究。首先分析了ＢＤＦ方法用于飞行器轨道约束实时控制模型问题时的缺陷，其后针对实际问题的特点构造了具有三阶收敛的代数约束算法，分析了该算法的数值稳定性，并对潜地式弹道约束实时控制问题及指标（ｉｎｄｅｘ）为２的单摆模型问题进行了实际仿真计算，理论分析以及数值结果表明代数约束算法对指标为２的半显式微分代数系统的实时控制计算是非常有效的。     

多时滞系统H∞状态反馈设计准则

文章首先提出了多时滞系统满足Ｈ∞设计指标的充分条件，根据这一条件，提出并证明了多时滞系统经状态反馈控制后的闭环系统满足Ｈ∞设计的指标的充分条件。     

日本新合纤的风格性能、发展过程及技术特征

80年代末期,由于高分子科学和化学纤维纺丝技术的进步,日本几家大的合纤企业相继向市场推出一大类风格新颖、手感柔软膨松、外观华贵高雅的全涤纶长丝或以涤长丝为主的织物,由于它们的性能深受消费者喜爱获得了“新合纤”的美称。介绍新合纤的风格性能、发展过程、技术特征及存在的问题。     

Two Methods for Deriving Members′Weights in Group Decision Making

1　IntroductionThe Analytic Hierarchy Process(AHP) ,introduced by Saaty[7] ,is one of the popular andpowerful technique for decision making,and has also been applied to group decisionproblems(Hannan[2 ] ,Khorramshahgol and Moustakis[5] ,Islei and Lockett[3] ) .TheWeighted Arithmetic Mean Method (WAMM) and Weighted Geometric Mean Method(WGMM) are the mostcommon group preference aggregation methods in AHP.In orderto use the WAMM and WGMM,one has to find the weights to be assigned…     

Effective Factors on Forming Precision in Patternless Casting Manufacturing Technique

The patternless casting manufacturing (PCM) technique, which adopts a new concept of double scanning method, combines the principle of discreteness and deposition with resin-bonded sand technique. This paper is to evaluate the dimensional accuracy of sand mould on PCM. The two important factors-the liquid penetration rule in the space of particles and the shape and dimension of the agglomeration unit body, which influence the process parameters such as scanning speed, layer thickness, liquid flux on dimension accuracy, and surface qualities, were investigated systematically, thus the theoretical basis for these parameters was provided. Experiments on rapid manufacturing of sand mould were carried out, and the results of the free penetration and the constraint penetration well verified the relationship of the two factors and the process parameters.     

Rapid Manufacturing of Sand Molds by Direct Milling

Direct milling of sand molds is an important development in rapid manufacturing of sand molds. Direct milling is an effective method for manufacturing single or small batches of cast parts. This paper describes experimental investigations to find sand blocks with the appropriate strength, to describe wear patterns of different tools (high-speed steel (HSS), carbide, and polycrystalline diamond (PCD) tools), and to analyze sand mold cutting mechanisms. The results show that the PCD tool outperformes the other tools in terms of tool life. Average flank wear and micro-tipping are the dominant tool failure modes in the sand mold milling process. With a flank wear limit of 0.3 mm, the PCD tool works continuously for about 70 h under the experimental conditions. The experimental results show that the cutting mechanism for direct milling sand molds differs from metal cutting.