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Poincaré and Poincaré-Cartan integral invariants of a generalized Hamiltonian system

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Communications in Nonlinear Science and Numerical Simulation 2001年第1期6卷 45-49页

作者： Yongxin GUO, Liyan JIANG and Ying YU (Department of Physics, Liaoning university, shenyang 110026, china Department of Electronics and Information engineering, Dandong Advanced Academy, Dandong 118000, china school of Science, shenyang university of Te Department of Physics Liaoning University Shenyang 110036 China Dept. of Electronics and Info. Eng. Dandong Advanced Academy Dandong 118000 China school of Science Shenyang University of Technology Shenyang 110023 China

Without Darboux’s transformation, the traditional Hamiltonian formulation of dynamical systems is only suitable to conservative systems or self-adjoint systems. Based on an extension of dynamic space of Birkhoffian systems to a generalized phase space by intro- ducing dummy variables, a generalized Hamiltonian canonical formulation of general systems is constructed, which admits symplectic structure. There exist integral invariants of Poincare and Poincare-Cartan’s type for such systems.

关键词： Birkhoffian systems symplectic structure integral invariants

High-voltage transmission tower-line system subjected to disaster loads

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Progress in Natural Science:Materials International 2006年第9期16卷 899-911页

作者： LI Hongnan and BAI Haifeng ( State Key Laboratory of Coastal and Offshore engineering, school of Civil and Hydraulic engineering, Dalian university of technology, Dalian 116024, china china Railway No. 9 Group Co., Ltd., shenyang 110013, china) [a]State Key Laboratory of Coastal and Offshore engineering School of Civil and Hydraulic Engineering Dalian University of Technology Dalian China [b]china Railway No.9 Group Co. Ltd. Shenyang China

The high-voltage power transmission system is an important lifeline structure. It is significant for wide researches on the features and ability of the system subjected to earthquake and environmental loads. The promising prosperity of the system has been demonstrated around the world. The corresponding advances of the system with respect to the mechanism of loading action, analytical methods, experimental research measurements, structural vibration control, fatigue damage, lifetime prediction, and design methods are comprehensively discussed herein. Finally, further research work on dynamic response characteristics of high-voltage transmission tower-line system in the near future is predicted.

关键词： high-voltage power transmission tower-line system loading effects dynamic analysis experimental researches design theories.

New Solution to Surface Temperature of Casting Slab Measurement Based on Preceded Reflector and Multi-Wavelength

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Journal of Iron and Steel Research International 2012年第8期19卷 12-16页

作者： LIU Jun1, MA Jiao-cheng2, YANG Feng3, XIAO Hui1, RAO Li-min1 (1. school of Nuclear engineering and technology, East china Institute of technology, Fuzhou 344000, Jiangxi, china 2. school of Mechanical engineering and Automation, Northeastern university, shenyang 110004, Liaoning, china 3. school of Civil and Environmental engineering, East china Institute of technology, Fuzhou 344000, Jiangxi, china) [a] school of Nuclear engineering and technology East China Institute of Technology Fuzhou 344000 Jiangxi China [b] school of Mechanical engineering and Automation Northeastern University Shenyang 110004 Liaoning China [c] school of Civil and Environmental engineering East China Institute of Technology Fuzhou 344000 Jiangxi China

The surface temperature of casting slab is an important parameter in the metallurgy field. Because the surface emissivity is uncertain and also unknown, it is difficult to measure the slab surface temperature accurately. A method based on preceded reflector and multi-wavelength was put forward to deal with the difficulty in surface temperature measurement of casting slab. On the premise of preceded reflector and non-preceded reflector, the method establishes the radiation energy equations and works out the emissivity and temperature in the equations. Also, the multilayer modeling of casting slab surface and multiple reflection-absorption process modeling were built by Monte Carlo method. The temperature measuring method had been applied in the continuous casting field. In order to verify the measured result, the thermal imaging method was adopted when the slab surface emissivity was set by repeated tests. Finally, the measured and verified temperature curves keep a same tendency and the error of the values is lower than 5℃. The comparison result shows that the method can measure temperature accurately.

关键词： casting slab emissivity surface temperature preceded reflector multi-wavelength

Equilibrium and kinetic studies on the adsorption of VB_(12) onto CMK-3

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Chinese Chemical Letters 2007年第2期18卷 233-236页

作者： Zhuo Guo, Li Feng Wang, Zhan Gao, Wei Wei Zhang school of Materials Science and engineering, shenyang Institute of Chemical technology, shenyang 110142, china State Key Laboratory of Inorganic Synthesis and Preparative Chemistry, Jilin university, Changchun 130012, china [a]school of Materials Science and engineering Shenyang Institute of Chemical Technology Shenyang 110142 China [b]State Key Laboratory of Inorganic Synthesis and Preparative Chemistry Jilin University Changchun 130012 China

The adsorption of VB12 onto CMK-3 was studied as a function of temperature and initial VB12 concentration. The highest VB12 adsorption capacity was determined as 353.4 mg/g at 40℃. Adsorption data were well described by the Langmuir model, although they could be modelled by the Freundlich equation. The pseudo-first-order and pseudo-second-order kinetic models were applied to test the experimental data. The pseudo-second-oider kinetic model provided the best correlation of the experimental data compared to the pseudo-nrsi-order model.

关键词： Adsorption VB12 Equilibrium Kinetic

Delay-probability-distribution-dependent robust stability analysis for stochastic neural networks with time-varying delay

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Progress in Natural Science:Materials International 2009年第10期19卷 1333-1340页

作者： Jie Fu,Huaguang Zhang,Tiedong Ma school of Information Science and engineering,Northeastern university,Box 134,shenyang 110004,china [a]school of Information Science and engineering Northeastern University Box 134 Shenyang 110004 China

The delay-probability-distribution-dependent robust stability problem for a class of uncertain stochastic neural networks(SNNs) with time-varying delay is *** information of probability distribution of the time delay is considered and transformed into parameter matrices of the transferred SNNs *** on the Lyapunov-Krasovskii functional and stochastic analysis approach,a delay-probability-distribution-dependent sufficient condition is obtained in the linear matrix inequality(LMI) format such that delayed SNNs are robustly globally asymptotically stable in the mean-square sense for all admissible *** important feature of the results is that the stability conditions are dependent on the probability distribution of the delay and upper bound of the delay derivative,and the upper bound is allowed to be greater than or equal to ***,numerical examples are given to illustrate the effectiveness and less conservativeness of the proposed method.

关键词： Delay-probability-distribution-dependent Stochastic neural networks Time-varying delay Linear matrix inequality

Surrogate model-assisted interactive genetic algorithms with individual’s fuzzy and stochastic fitness

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控制理论与应用（英文版） 2010年第2期8卷 189-199页

作者： Xiaoyan SUN, Dunwei GONG (school of Information and electrical engineering, china university of Mining and technology, Xuzhou Jiangsu 221116, china) school of Information and electrical engineering China University of Mining and Technology Xuzhou Jiangsu China

We propose a surrogate model-assisted algorithm by using a directed fuzzy graph to extract a user’s cognition on evaluated individuals in order to alleviate user fatigue in interactive genetic algorithms with an individual’s fuzzy and stochastic fitness. We firstly present an approach to construct a directed fuzzy graph of an evolutionary population according to individuals’ dominance relations, cut-set levels and interval dominance probabilities, and then calculate an individual’s crisp fitness based on the out-degree and in-degree of the fuzzy graph. The approach to obtain training data is achieved using the fuzzy entropy of the evolutionary system to guarantee the credibilities of the samples which are used to train the surrogate model. We adopt a support vector regression machine as the surrogate model and train it using the sampled individuals and their crisp fitness. Then the surrogate model is optimized using the traditional genetic algorithm for some generations, and some good individuals are submitted to the user for the subsequent evolutions so as to guide and accelerate the evolution. Finally, we quantitatively analyze the performance of the presented algorithm in alleviating user fatigue and increasing more opportunities to find the satisfactory individuals, and also apply our algorithm to a fashion evolutionary design system to demonstrate its efficiency.

关键词： Interactive genetic algorithms User fatigue Surrogate model Directed fuzzy graph Fuzzy entropy

electrically Conductive Concrete for Heating Using Steel Bars as Electrodes

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Journal of Wuhan university of technology(Materials Science) 2010年第3期25卷 523-526页

作者：侯作富 school of Mechanical engineering Yangtze University

The steel bars with good electrical conductivity were used as two kinds of electrodes in the making of carbon fiber（CF） electrically conductive concrete for *** results of the pertinent experiments illustrate the design is *** change in electrical resistivity over three years＇ hydration time was studied when steel bars were used as lateral face electrodes and top bottom surface electrodes *** temperature rise test was conducted to verify the heating properties of two kinds of *** only the study can reduce the CF volume content of electrically conductive concrete for heating to 0.58% or 0.36% according to different design,but also it will enhance the carrying capacity of the concrete roadway for heating.

关键词： steel bar carbon fiber electrical resistivity temperature rise

International Transferring Trend in Manufacturing Industry

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厦门大学学报（自然科学版） 2002年第S1期41卷 222-223页

作者： ZHAO Xin-jun 1, XU Li-hui 2 (1. school of Mechanical engineering and Automation, Northeastern Unive rsity, shenyang 110004, china 2. school of Business Administration, Northea stern university, shenyang 110004, china)

This paper addressed the international transferring t endency of manufacturing industry one by one as follows: (1) The developed count ries realize manufacturing industry structure upgrade reling on worldwide tr ansference not only domestic transference. On one hand, the TNCs make cross-inv estments, transnational merger & acquisition so as to achieve the optimum colloc ation of R&D resources, and obtain innovation in knowledge and technology. On th e other hand, the developed countries transfer labor and resource intensive indu stry as well as the labor-intensive link of the production chain in highly tech nology industry to the developing countries, to make their industrial structure escalation. (2) The adjustment and upgrade of manufacturing industry presents "m ulti-step type". First, the object of international transference substitutes th e capital-intensive industry and maturing industry with complicate technique fo r the industry with labor-intensive, simple technique or higher pollution, or s ubstitutes non-core complex technological procedure and parts and components fo r assembly in manufacturing process. Secondly, technology transference forms "br ain-hand and foot" pattern, i.e. the developed countries are increasingly p aying more and more attention to the research and control of core technology, th us transferring simple technique and labor-intensive procedure in higher scienc e and technology. Thirdly, the developed countries begins to transfer both capit al and technology intensive production, as well as transfer certain procedures i n higher technology production process to a few developing countries, even t o transfer parts of R & D to developing countries. (3) TNCs promote the global m anufacturing network (GMN) by recombination and transfer. TNCs organize producti on, trade, technological research and transference through foreign direct invest ment (FDI) all over the world, as a result, GMN makes the national competence no longer depend on absolu

关键词： manufacturing industry international transferrin g tendency

Transient temperature field of a friction pair in a HVD device of a belt conveyor

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Mining Science and technology 2010年第6期20卷 904-907页

作者： XIE Fangwei, HOU Youfu school of Mechanical and electrical engineering, china university of Mining & technology, Xuzhou 221008, china [a] school of Mechanical electrical engineering China University of Mining & Technology Xuzhou 221008 China

To show the distribution of a temperature field on a steel disk and to prolong the service life of a friction pair in a Hy-dro-Viscous Drive (HVD) device, a theoretical model of a transient temperature field was established, based on the theory of heat conduction. This theoretical model was solved using a finite element method. The results show that the surface temperature of the steel disk does not increase consistently as a function of the radius; the highest temperature appears short of the maximum radius. The relationship between the surface temperature and the mixed friction time is exponential. With a friction time of 15 s, the tem-perature reached 465.9 °C. Simultaneously, the internal thermal stress is larger than the yield stress of the material, causing a warping deformation of the steel disk. The largest axial deformation is 0.32 mm. The results of the experiment suggest that the de-formation is the same as that obtained from numerical simulation. Therefore, deformation of the steel disk must be considered dur-ing the study of the characteristics of a HVD.

关键词： hydro-viscous steel disk temperature field deformation numerical simulation