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AN IMPLEMENTATION OF A MODEL MANAGEMENT SySTEM

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中国有色金属学会会刊：英文版 1995年第4期5卷 151-157页

作者： Chen, XH Takahara, y CENT S UNIV TECHNOL DEPT BUSINESS ADMCHANGSHA 410083PEOPLES R CHINA TOKyO INST TECHNOL TOKYO 152JAPAN

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ＡＮＩＭＰＬＥＭＥＮＴＡＴＩＯＮＯＦＡＭＯＤＥＬＭＡＮＡＧＥＭＥＮＴＳＹＳＴＥＭＣｈｅｎＸｉａｏｈｏｎｇ（ＤｅｐａｒｔｍｅｎｔｏｆＢｕｓｉｎｅｓｓＡｄｍｉｎｉｓｔｒａｔｉｏｎＣｅｎｔｒａｌＳｏｕｔｈＵｎｉｖｅｒｓｉｔｙｏｆＴｅｃｈｎｏｌｏｇｙ，Ｃｈａ...

关键词： general systems theory(GST) model management model description language(MDL) model integration environment(MIE) decision support system(DSS) menu system annual production planning

DISPERSION AND TENSILE BEHAVIOR OF POLyPROPyLENE/MONTMORILLONITE NANOCOMPOSITES PRODUCED VIA MELT INTERCALATION

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Chinese Journal of Polymer Science 2003年第3期21卷 359-368页

作者： y.Men 傅强 Department of Physics Albert-Ludwigs University D-79104 Freiburg Germany Department of Polymer Science & Materials Sichuan University State Key Laboratory of Polymer Materials Engineering Chengdu 610065 China

Most of the articles on polymer nanocomposites focus on the importance of chemistry used to modify the surface of the clay, usually montmorillonite (MMT), and characterization of the nano-scale structure obtained. The role and importance of processing were also discussed recently. However, few papers concerning the correlation between morphology of MMT and mechanical properties were published. In order to understand. the tensile behavior of PP/Montmorillonite (MMT) nanocomposites better, and to further improve the reinforcement efficiency, we first prepared the PP nanocomposites via direct melt intercalation using conventional twin-screw extrusion. The dispersion and tensile property of the composites were then investigated by SEM, XRD, TEM and a video-controlled tensile set-up. The macroscopic and microscopic dispersion of MMT in PP matrix was verified by XRD and TEM, combined with SEM. The tensile properties were obtained by video-controlled tensile set-up, which gives true stress-strain curve. It was found that a partly intercalated and partly exfoliated structure (also called incomplete exfoliation) existed in the system. Though the tensile strength of PP nanocomposites is not much improved in engineering stress-strain curves, more than 20% increase of true stress was found in a true stress-strain experiment at high true strain, which indicates that only oriented silicate layers can have a big effect on tensile properties: Not only orientation of silicate platelets but also the degree of exfoliation is a key factor to determine the reinforcement efficiency. The reinforcement efficiency of MMT has been discussed based on the 'continuum' Halpin-Tsai equations. A good agreement was found between experimental data and theoretical prediction by changing N value (number of platelets per stack) which corresponding to different state of the dispersion of MMT in PP matrix.

关键词： polypropylene/montmorillonite nanocomposites dispersion orientation tensile property

A SPLINE METHOD FOR SOLVING TWO-DIMENSIONAL FREDHOLM INTEGRAL EQUATION OF SECOND KIND WITH THE HyPERSINGULAR KERNEL

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Journal of Computational Mathematics 2001年第3期19卷 225-230页

作者： Wang, RH Lu, y Dalian Univ Technol Inst Math Sci Dalian 116024 Peoples R China

Provides information on a study which proposed a spline method for solving two-dimensional Fredholm Integral Equations of second kind space with hypersingular kernels. Details on the quasi-interpolating operators; Inf... 详细信息

关键词： hypersingular integral finite-part integral quasi-interpolating operator nonuniform type-2 triangulation

Theory and Modeling of Phase Transformations under Stress in Steel

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材料热处理学报 2004年第5期25卷 1-7页

作者： T.y. Hsu School of Materials Science and Engineering Shanghai Jiao Tong University Shanghai 200030 China

Thermodynamic prediction of the increment of the formation temperature of proeutectoid ferrite by appliedstress is nearly consistent with the wxperfimental *** models for ferrite,pearlite and bainite transformations can be shown as modified Johnson-Mehl-Avrami equation in which parameter b() varies with the level of applied *** effects of tensile and compressive stresses on enhancement of the ferrite/pearlite and bainite transformations are discussed,The necessity and approach of modification of additivity hypothesis are introduced and the results from modified equation in which some parameters are obtained by rfegression of two experimental results or taken from TTT and CCT diagrams of a cerftain steel are superior than that from Scheil’s *** calculation of Ms and nucleation kinetics equations of martensitic transformation under stress are *** of phase trasformations under stress in ferrous alloys is briefly

关键词：钢相位转换受力状态热力学动力学成核现象相加性假设铁合金

COMPLEXITy AND INTRANSITIVITy IN TECHNOLOGICAL DEVELOPMENT

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Journal of Systems Science and Systems Engineering 2014年第2期23卷 128-152页

作者： Alexander y.KLIMENKO The University of Queensland

This paper investigates the existence of a fundamental link between two disciplines that emerged during last few decades： complexity science and advanced engineering. During this time many industries, especially those related to the high-tech end of technological development, have faced the problem of increasing complexity of design, production and operation. Industrial projects have grown to become multidisciplinary, tightly interconnected, costly and difficult to control and predict. Two trends can be identified in this respect： one is the consistent effort of systems engineering in reducing the uncertainties of complex industrial operations and the other is the effort undertaken in complexity studies to account for uncertainties present in the real world. In this work, we provide a brief overview of recent developments in advanced engineering and give a consistent interpretation of technological evolution from the perspective of complexity science in general and complex competitive systems （CCS） in particular. CCS is a general framework that was recently developed for analysis of complex systems involving competition. Transitivity of the decision-making process and the cyclic nature of technological progress are considered. Correctness of intransitive decisions is inherently relativistic： the same decisions can be seen as correct or incorrect when considered from different perspectives. When treated simplistically, intransitivity may seem to be illogical but, nevertheless, it is common in nature and needs to be studied. CCS provides a formalised scientific framework for analysis of intransitivity and establishes the existence of an important connection linking complexity and uncertainty with intransitivity. Implications of intransitivity for engineering decision-making and strategic planning are considered in the context of CCS. A working example of intransitivity in competition between major car mantifacturers is presented.

关键词： Complexity technology strategy systems engineering industrial strategy and decision-making complex competitive systems.

Effect of Temperature on Material Transfer Behavior at Different Stages of Friction Stir Welded 7075-T6 Aluminum Alloy

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Journal of Materials Science & Technology 2013年第10期29卷 955-960页

作者： S.D.Ji y.y.Jin y.M.yue S.S.Gao y.X.Huang L.Wang Faculty of Aerospace Engineering Shenyang Aerospace University State Key Laboratory of Advanced Welding and Joining Harbin Institute of Technology

In this work, the morphologies of weld of 7075-T6 aluminum alloy via friction stir welding （FSW） were analyzed by optical microscopy, the temperature field was attained by numerical simulation, and the effect of temperature on material transfer behavior in the thermal-mechanical affected zone （TMAZ） at different stages was mainly investigated. The FSW process consists of three stages. It is very interesting to find that the maximum transfer displacement of material appears at the final stage of welding process, then at the stable stage and at the initial stage, which results from the difference of peak temperatures at different stages. At any stage, the material in TMAZ near the surface of weld transfers downwards, the material in the middle of weld moves upwards and the material near the bottom of weld hardly moves. In any cross section of weld, the largest transfer displacement of material appears in the middle of weld. The increase of rotational velocity and the decrease of welding speed are both beneficial to the transfer displacement of material in the middle of weld.

关键词： Friction stir welding 7075-T6 aluminum alloy Thermal-mechanical affected zone Material transfer Numerical simulation

Frequency Veering of Rotating Metal Porous Twisted Plate with Cantilever Boundary Using Shell Theory

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Acta Mechanica Solida Sinica 2022年第2期35卷 282-302页

作者： y.y.Liu y.X.Hao W.Zhang L.T.Liu S.W.yang y.T.Cao College of Mechanical Engineering Beijing Information Science and Technology UniversityBeijing 100192China College of Mechanical Engineering Beijing University of TechnologyBeijing 100124China

The frequency veering of a metal porous rotating cantilever twisted plate with twist angle and stagger angle is *** porous materials may have the characteristics of gradient or uniform distribution along the thickness *** on the classical shell theory,considering the influence of centrifugal force produced by high-speed rotation,the free vibration equations of a rotating cantilever twisted plate are *** the polynomial function and Rayleigh-Ritz method,the natural frequencies and mode shapes of the metal porous cantilever twisted plate in both static and rotating states are *** accuracy of the present theory and calculation results is confirmed by a comparison between them and the results available from the literature and those obtained from *** influences of the thickness ratio,porosity,twist angle,stagger angle and rotational velocity on the frequency veering and mode shape shift of the rotating cantilever twisted plate with porous material under three different distributions are *** should be mentioned that the frequency veering accompanied by mode shape shift occurs in both static and dynamic states.

关键词： Frequency veering Rotating twisted plate Cantilever boundary Metal porous

Nucleon-pair approximation with uncoupled representation

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Chinese Physics C 2021年第5期45卷 129-140页

作者： y.Lei y.Lu y.M.Zhao School of National Defense Science and Technology Southwest University of Science and TechnologyMianyang 621010China College of Physics and Engineering Qufu Normal UniversityQufu 273165China Shanghai Key Laboratory of Particle Physics and Cosmology School of Physics and AstronomyShanghai Jiao Tong UniversityShanghai 200240China Collaborative Innovation Center of IFSA(CICIFSA) Shanghai Jiao Tong UniversityShanghai 200240China

In this paper,we propose an approach to nucleon-pair approximation(NPA)with m-scheme bases,in which the collective nucleon pairs are represented in terms of antisymmetric matrices,and commutations between nucleon pairs are given using a matrix multiplication that avoids angular-momentum couplings and *** the present approach significantly simplifies the NPA ***,it is formulated on the same footing with and without isospin.

关键词： uncoupled representation nucleon-pair approximation formalism computational efficiency

Mechanosynthesis and mechanochemical treatment of bismuth-doped vanadium phosphorus oxide catalysts for the partial oxidation of n-butane to maleic anhydride

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Journal of Natural Gas Chemistry 2008年第3期17卷 232-237页

作者： y. H. Taufiq-yap y.C. Wong y. Kamiya W.J. Tang Putra Center for Catalysis Science and Technology Department of Chemistry Faculty of Science Universiti Putra Malaysia 43400 UPM Serdang Selangor Darul Ehsan Malaysia Graduate School of Environmental Science Hokkaido Universit3 Sapporo 060-0810 Japan

Three Bi-doped vanadyl pyrophosphate catalysts were prepared via dihydrate route （VPD method）, which consisted of different preparation methods including mechanosynthesis, mechanochemical treatment, and the conventional reflux method. The catalysts produced by the above three methods were characterized by x-ray diffraction （XRD）, scanning electron microscopy （SEM）, and temperature programmed reduction （TPR）. Catalytic evaluation for the partial oxidation of n-butane to maleic anhydride （MA） was also carried out. The XRD patterns of all the Bi-doped catalysts showed the main peaks of pyrophosphate phase. Lower intensity peaks were observed for the mechanochemically treated Bi-doped catalyst （VPDBiMill） with two additional small peaks corresponding to the presence of a small amount of V5＋ phase. The TPR profiles showed that the highest amount of active oxygen species, i.e, V4＋–O- pair, responsible for n-butane activation, was removed from VPDBiMill. Furthermore, from the catalytic test results, the graph of selectivity to MA as a function of the conversion of n-butane demonstrated that VPDBiMill was the most selective catalyst. This suggests that the mechanochemical treatment of vanadium phosphate catalyst （VPDBiMill） is a potential method to improve the catalytic properties for the partial oxidation of n-butane to maleic anhydride.

关键词： mechanosynthesis mechanochemical treatment bismuth vanadyl pyrophosphate