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Micromechanical analysis of interaction energy for SMA reinforced composite

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Science china(Technological Sciences) 2009年第3期52卷 610-616页

作者： ZHU YuPing1,2. DUI GuanSuo1 & DUO Liu3 1 Institute of Mechanics, Beijing jiaotong University, Beijing 100044, china 2.Department of Engineering Mechanics, Jiangsu University, Zhenjiang 2.2.13, china 3 State Key Lab of Crystal Materials, shandong University, jinan 2.0100, china Institute of Mechanics Beijing Jiaotong University Beijing 100044 China Department of Engineering Mechanics Jiangsu University Jiangsu Zhenjiang 212013 China State Key Lab of Crystal Materials Shandong University Jinan 250100 China

The energy of the interaction between the matrix and the inclusions in shape memory alloy (SMA) re- inforced composite is one of the most important and complicated parts in thermodynamic constitutive theory. In this paper, the interaction energy is derived based on the classical theory of micromechanics and the thermodynamic theory. The SMA composite is treated as three phases, namely the austenitic phase, the martensite phase and the matrix phase. The interaction among the three phases is analyzed in a way close to the fact. The present expression is used to calculate the interaction energy of a typical SMA composite with attentions paid to understand of the effects of the matrix material, the fiber ge- ometry, and the fiber/matrix volume ratio. It is shown that the method developed in this paper is credible compared with the references. Some useful conclusions are obtained.

关键词： shape memory alloy interaction energy SMA composite micromechanics thermodynamics

Polling Algorithm Based on Traffic Burst Characteristics of Broadband Wireless Access Systems

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Journal of Shanghai jiaotong university(Science) 2011年第4期16卷 429-435页

作者：李秀媛李炜吴晓娟张云峰 School of Computer Science and Technology Shandong Economy University School of Information Science and Engineering Shandong University shandong Provincial Key Laboratory of Digital Media Technology

In this paper,we propose a novel polling algorithm to decrease the number of idle slots and collission slots during the polling cycle by evaluating the bandwidth request of the subscribe stations(SSs) in the next polling cycle for broadband wireless access(BWA) *** firstly analyze the feature of silent time intervals and deduce the Hurst index which symbolizes the degree of self-similarity and long-relative *** we represent the inactive OFF time intervals by the Pareto model and estimate the shape parameterαby the group measured *** we can evaluate the transmission probability of a silent SS before the next polling cycle. By this algorithm,we can find the optimal transmission opportunities for the base station(BS) to achieve the least collision or void timeslots in order to achieve the largest bandwidth *** theoretical analysis and simulation results show that this polling algorithm can improve the performance for BWA system.

关键词： broadband wireless access(BWA) systems polling algorithm bandwidth allocation self-similarity

Separate critical condition for ultrasonic vibration assisted grinding

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Journal of Shanghai University(English Edition) 2009年第5期13卷 391-395页

作者：张洪丽张建华 Department of Construction Machinery Shandong Jiaotong University School of Mechanical Engineering Shandong University

Separate characteristic of the tangential ultrasonic vibration assisted grinding (TUAG) machining is analyzed based on TUAG process, and a critical speed formula is given to correctly set the machining parameters to insure the separate characteristics of TUAG process. The critical speed is not only related to the ultrasonic vibration amplitude and frequency, but also to the grinding wheel velocity and the cutting point space, and the grinding force can be decreased during the TUAG process with separability. Grinding force experiments are conducted, and the experimental results are in good agreement with the theoretical results.

关键词： tangential ultrasonic vibration assisted grinding (TUAG) critical speed separate characteristic

Influences of Heat Treatments on Crystallization in SiO_2.Al_2._3-MgO-K_2.-F Glass-ceramics

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Journal of Wuhan University of Technology(Materials Science) 2011年第3期26卷 403-406页

作者：田清波 School of Materials Science and Engineering Shandong Jianzhu University

Five kinds of heating treatment processing were chosen according to the experiment result of differential scanning calorimeter to prepare SiO2.Al2.3-MgO-K2.-F glass ceramics *** effects of heat treatment processing on the crystallization of these samples were explored by X-ray diffraction and scanning electron microscopy *** results indicate that phase separations can occur in the bulk regions of the glass sample when holding at 670 ℃ for 3 *** phase separation can accelerate the precipitation of the crystallization phase： when the temperature directly rises to 950 ℃ after the phase separation,there are mainly interlocked plate-shapes mica phases;If holding at 860 ℃ for 3 h first after the phase separation,the star-shape cordierite phases form;Thereby,elevating temperature to 950 ℃ and holding for 1 h will bring plate-shapes mica phases growing at inter-phases of the star-shape cordierite and finally the homogeneously distributed mica- cordierite composites ***,if heating at 950 ℃ directly without holding at 670 ℃,there is a small quantity of phase separation appearing at 670 ℃ and a little crystallization phases precipitating at last.

关键词： thermal decomposition mechanism kinetics Siderite

Establishment of bovine prion peptide-based monoclonal antibodies for identifying bovine prion

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Science china(Life Sciences) 2009年第8期52卷 754-760页

作者： ZHAO Li1,HOU XinSheng5,JI Rong2.HAN ChunHui2.YU XiuPing3,HONG Tao4,5 1 Department of Laboratory Science of Microbiology,School of Public Health,shandong University,jinan 2.0012.{2. 2.Institute of Nutrition and Food Safety,Chinese Center of Disease Prevention and Control,Beijing 10002.,{2. 3 Department of Microbiology,School of Medicine,shandong University,jinan 2.0012.{2. 4 Institute of Virus Disease Prevention and Control,Chinese Center for Disease Control and Prevention,Beijing 100052.{2. 5 Institute of Biological Science and Technology,School of Science,Beijing jiaotong University,Beijing 100044,{2. Department of Laboratory Science of Microbiology School of Public Health Shandong University Jinan 250012 China Institute of Nutrition and Food Safety Chinese Center of Disease Prevention and Control Beijing 100021 China Department of Microbiology School of Medicine Shandong University Jinan 250012 China Institute of Virus Disease Prevention and Control Chinese Center for Disease Control and Prevention Beijing 100052 China Institute of Biological Science and Technology School of Science Beijing Jiaotong University Beijing 100044 China

To obtain high titer monoclonal antibodies(McAbs) which can react with mammalian prion protein(PrP),Balb/C mice were immunized with bovine(Bo) PrP peptide(BoPrP 2.9-2.8 aa) coupled to keyhole limpet hemocyanin(KLH).The hybridoma cell lines secreting monoclonal antibodies against the peptide were established by cell fusion and *** obtained McAbs were applied to detect recombinant human,bovine and hamster PrP,cellular prion protein(PrPc) in normal bovine brain and pathogenic scrapie prion protein(PrPSc) accumulated in the medulla oblongata of bovine spongiform encephalopathy(BSE)specimen with Western blot and immunohistochemical detection,*** current procedure might offer a simple,feasible method to raise high titer antibodies for studying biological features of PrP in mammals,as well as detection of transmissible spongiform encephalopathy(TSE) and diagnosis of BSE,in particular.

关键词： prion monoclonal antibody Western blot immunohistochemistry ELISA

Mechanical Behavior of Tubular T-joint after Fire

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Journal of Shanghai jiaotong university(Science) 2011年第1期16卷 97-104页

作者：靳猛赵金城常静刘明路 School of Naval Architecture Ocean and Civil EngineeringShanghai Jiaotong University Construction and Infrastructure Department Shandong Jiaotong University

This paper presents experimental results of the post-fire behavior of tubular *** research aims at the failure modes and the residual strengths of the T-joints after *** tests of full-scale tubular T-joints are *** first one is carried out to study the mechanical behavior of T-joints under ambient *** other two tests are performed to study the influence of pre-load,heating and cooling phase on residual load-bearing capacity of the tubular *** test results show that the sustained axial load on the brace has remarkable influence on the residual deflection of the T-joints which is cooled down to room *** results of the experiments also indicate that the axial load level and heating and cooling history have more significant effects on the compressive stiffness of the T-joints than the residual *** the numerical study,the result of finite element model agrees well with the test *** work in this paper provides a basis for further parametric analysis and theoretical study on the structural evaluation after fire.

关键词： T-joints post-fire residual strength numerical analysis

A Total Generalized Optimal Velocity Model and Its Numerical Tests

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Journal of Shanghai jiaotong university(Science) 2008年第2期13卷 166-170页

作者：朱文兴刘允才 Department of Automation Shanghai Jiaotong University School of Control Science and Engineering Shandong UniversityJinan 250061China

A car-following model named total generalized optimal velocity model （TGOVM） was developed with a consideration of an arbitrary number of preceding vehicles before current one based on analyzing the previous models such as optimal velocity model （OVM）, generalized OVM （GOVM） and improved GOVM （IGOVM）. This model describes the physical phenomena of traffic flow more exactly and realistically than previous models. Also the performance of this model was checked out by simulating the acceleration and deceleration process for a small delay time. On a single circular lane, the evolution of the traffic congestion was studied for a different number of headways and relative velocities of the preceding vehicles being taken into account. The simulation results show that TGOVM is reasonable and correct.

关键词： car-following model multi-interaction relative velocities headways

Optimal Training Design and Placement for MIMO Orthogonal Frequency Division Multiplexing Channel Estimation

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Journal of Shanghai jiaotong university(Science) 2010年第1期15卷 58-63页

作者：林成裕钱良张文军徐友云李洪烈 Institute of Image Communication and Information Processing Shanghai Jiaotong University Shanghai Key Laboratory of Digital Media Processing and Transmissions Shanghai Jiaotong University Qingdao Branch of Naval Aeronautical Engineering Institute

This paper deals with optimal training design and placement over multiple orthogonal frequency division multiplexing(OFDM) symbols for the least squares(LS) channel estimation in multiple-input multipleoutput(MIMO) OFDM ***,the optimal pilot sequences over multiple OFDM symbols are derived by co-cyclic Jacket matrices based on the minimum mean square error(MSE) of the LS channel ***,an enhanced channel estimation method using sliding window is proposed to improve further the performance for the optimal pilot sequences in fast-varying *** results show that the enhancedmethod can efficiently improve the performances for the optimal pilot sequences over two and four OFDM symbols,especially in fast-varying channels.

关键词： co-cyclic Jacket matrix optimal pilot sequences channel estimation multiple-input multiple-output orthogonal frequency division multiplexing (MIMO-OFDM)

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消耗系数矩阵的逆向经济调整

山东大学学报（理学版） 2003年第5期38卷 52-55页

作者：徐大举刘吉晓史昱山东大学数学与系统科学学院山东济南250100 山东交通学院基础部山东济南250023

利用RAS法和正特征矢量法 ,根据实际经济意义 ,从理论上给出逆向调整直接消耗系数矩阵的一种方法 ,可以节省大量的人力物力 ,并能对宏观经济各部门的发展加以分析 .

关键词：直接消耗系数矩阵正特征矢量法替代效应制造效应