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Dynamic damage and stress-strain relations of ultra-high performance cementitious composites subjected to repeated impact

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science china(Technological sciences) 2010年第6期53卷 1520-1525页

作者： LAI JianZhong1 & SUN Wei2 1 department of Materials science and Engineering,nanjing University of science and technology,nanjing 210094,china 2 College of Materials science and Engineering,Southeast University,nanjing 211189,china 1. department of Materials science and Engineering Nanjing University of Science and Technology Nanjing 210094 China2. College of Materials Science and Engineering Southeast University Nanjing 211189 China

Ultra-high performance cementitious composites (UHPCC) were prepared by replacing 60% of cement with ultra-fine industrial waste *** dynamic damage and compressive stress-strain relations of UHPCC were studied using split Hopkinson pressure bar (SHPB).The damage of UHPCC subjected to repeated impact was measured by the ultrasonic pulse velocity *** show that the dynamic damage of UHPCC increases linearly with impact times and the abilities of repeated impact resistance of UHPCC are improved with increasing fiber volume *** stress waves on impact were recorded and the average stress,strain and strain rate of UHPCC were calculated based on the wave propagation *** effects of strain rate,fibers volume fraction and impact times on the stress-strain relations of UHPCC were *** show that the peak stress and elastic modulus decrease while the strain rate and peak strain increase gradually with increasing impact times.

关键词： ultra-high performance cementitious composites (UHPCC) split Hopkinson pressure bar (SHPB) repeated impact damage stress-strain

Characteristics of fMRI BOLD signal and its neurophysiological mechanism

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Progress in Natural science:Materials International 2007年第6期17卷 630-638页

作者： Zhao Xiaohu1,2, Wu Yigen3.and Guo Shengli3.1. College of Life sciences, Zhejiang University, Hangzhou 3.0058, china 2. Imaging department of Tongji Hospital of Tongji University, Shanghai 200065, china 3. College of Mathematics and Physics, nanjing University of Information science and technology, nanjing 210044, china) College of Life sciences Zhejiang University Hangzhou 310058 China Imaging department Tongji Hospital Tongji University Shanghai 200065 China College of Mathematics and Physics Nanjing University of Information Science and Technology Nanjing 210044 China

The functional magnetic resonance imaging (fMRI) based on blood oxygen level dependent (BOLD) contrast has emerged as one of the most potent noninvasive tools for mapping brain function and has been widely used to explore physiological, pathological changes and mental activity in the brain. Exploring the nature and property of BOLD signal has recently attracted more attentions. Despite that great progress has been made in investigation of the characteristics and neurophysiological basis, the exact nature of BOLD signal remains unclear. In this paper we discuss the characteristics of BOLD signals, the nonlinear BOLD response to external stimuli and the relation between BOLD signals and neural electrophysiological recordings. Furthermore, we develop our new opinions regarding nonlinear BOLD response and make some perspectives on future study.

关键词： functional magnetic resonance imaging blood oxygen level dependent nonlinear response neural electrophysiological activity.

Web Application Comprehension Based on Dependence Analysis

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Wuhan University Journal of Natural sciences 2004年第5期9卷 731-734页

作者： WU Jun-hua 1,2 , XU Bao-wen 1 , JIANG Ji-xiang 1 1.department of computer science and Engineering, Southeast University, {3. 210096, Jiangsu, china 2.College of computer science and Engineering, {3. University of technology, {3. 210009, Jiangsu , china Southeast University Department of Computer Science and Engineering Nanjing Jiangsu China (GRID:grid.263826.b) (ISNI:***) Najing University of technology College of Computer Science and Engineering Nanjing Jiangsu China (GRID:grid.41156.37) (ISNI:***) Southeast University Department of Computer Science and Engineering Nanjing Jiangsu China (GRID:grid.263826.b) (ISNI:***)

Many research indicate a lot of money and time are spent on maintaining and modifying program delivered. So the policies to support program comprehension are very important. Program comprehension is a crucial and difficult task. Insufficient design, illogical code structure, short documents will enhance the comprehensive difficulty. Developing Web application is usually a process with quick implementation and delivery. In addition, generally a Web application is coded by combining mark language statements with some embedded applets. Such programming mode affects comprehension of Web applications disadvantageously. This paper proposes a method to improving understanding Web by dependence analysis and slice technology. Key words Web application comprehension - program dependence - hyper graph - pogram slicing CLC number TP 3.1 Foundation item: Supported in part by the Young Scientist’s Fund of NSFC (603.3.66, 603.3.24). National Grand Fundamental Research 973.Program of china (2002CB3.2000) and National Research Foundation for the Doctoral Program of Higher Education of chinaBiography: WU Jun-hua (1965-), female, Ph. D. research direction: software engineering.

关键词： Web application comprehension program dependence hyper graph pogram slicing

Basin filling algorithm for the circular packing problem with equilibrium behavioral constraints

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science china(Information sciences) 2010年第5期53卷 885-895页

作者： LIU JingFa1& LI Gang2 1School of computer and Software, nanjing University of Information science & {3., nanjing 210044, china 2School of Mathematics and Physics, nanjing University of Information science & {3., nanjing 210044, china 1. School of computer and Software Nanjing University of Information Science & Technology Nanjing 210044 China2. School of Mathematics and Physics Nanjing University of Information Science & Technology Nanjing 210044 China

With the background of the satellite module layout design, the circular packing problem with equilibrium behavioral constraints is a layout optimization problem and NP-hard problem in math. For lack of a powerful optimization method, this problem is hard to solve. The energy landscape paving (ELP) method is a class of stochastic global optimization algorithms based on the Monte Carlo sampling. Based on the quasiphysical strategy and the penalty function method, the problem is converted into an unconstrained optimization problem. Here by combining the improved ELP method, the gradient method based on local search and the heuristic configuration update mechanism, a new global search algorithm, basin filling algorithm, is put forward. The numerical results show that the proposed algorithm is effective to solving the circular packing problem with equilibrium behavioral constraints, and is easy to be popularized to other layout optimization problems.

关键词： equilibrium behavioral constraints packing problem layout optimization

A new smoothing scheme for mathematical programs with complementarity constraints

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science china Mathematics 2010年第7期53卷 1881-1890页

作者： YAN Taodepartment of Information and Computational sciences, College of science, {3. University of science and technology, {3. 210094, china 1. department of Information and Computational sciences College of Science Nanjing University of Science and Technology Nanjing 210094 China

In this paper, we consider a mathematical program with complementarity constraints (MPCC). We present a new smoothing scheme for this problem, which makes the primal structure of the complementarity part unchanged mostly. For the new smoothing problem, we show that the linear independence constraint qualification (LICQ) holds under some conditions. We also analyze the convergence behavior of the smoothing problem, and get some sufficient conditions such that an accumulation point of stationary points of the smoothing problems is C (M, B)-stationarity respectively. Based on the smoothing problem, we establish an algorithm to solve the primal MPCC problem. Some numerical experiments are given in the paper.

关键词： mathematical program with complementarity constrains MPEC-LICQ B-stationarity C-stationarity M-stationarity

Studies on the Plasma Shielding of 1.06μm Laser on the Aluminum Target

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Chinese Journal of Lasers 1995年第5期B4卷 417-422页

作者： LU Jian NI Xiaowu HE Anzhi (department of Applied Physics,nanjing of science & {3.,200 Xiaolingwei, nanjing 210094,china) nanjing Univ of science & Technology Nanjing China

ＳｔｕｄｉｅｓｏｎｔｈｅＰｌａｓｍａＳｈｉｅｌｄｉｎｇｏｆ１．０６μｍＬａｓｅｒｏｎｔｈｅＡｌｕｍｉｎｕｍＴａｒｇｅｔＬＵＪｉａｎ；ＮＩＸｉａｏｗｕ；ＨＥＡｎｚｈｉ（ＤｅｐａｒｔｍｅｎｔｏｆＡｐｐｌｉｅｄＰｈｙｓｉｃ... 详细信息

ＳｔｕｄｉｅｓｏｎｔｈｅＰｌａｓｍａＳｈｉｅｌｄｉｎｇｏｆ１．０６μｍＬａｓｅｒｏｎｔｈｅＡｌｕｍｉｎｕｍＴａｒｇｅｔＬＵＪｉａｎ；ＮＩＸｉａｏｗｕ；ＨＥＡｎｚｈｉ（ＤｅｐａｒｔｍｅｎｔｏｆＡｐｐｌｉｅｄＰｈｙｓｉｃｓ，ＮａｎｊｉｎｇｏｆＳｃｉｅｎｃ...

关键词： laser plasma plasma shielding

TRANSMISSION MOMENTARY EFFICIENCY BASED ON THE D'ALEMBERT-LAGRANGE EQUATION FOR INVOLUTES GEARS

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Chinese Journal of Mechanical Engineering 2004年第2期17卷 272-275页

作者： Liang Yi Lai Changying School of Mechanical Engineering,nanjing University of science and technology,nanjing 210094, china School of Mechanical Engineering Nanjing University of Science and Technology Nanjing 210094 China department of science and technology Studies University College London WC1E 6BT UK

The D'Alembert-Lagrange equation is introduced and used to derive theformulas of momentary efficiency for external gearing of standard involutes spur gears. The gearingswith correct and increased center distance are discussed. The momentary efficiency formula iscalculated and analyzed using software Matlab. The derived formula of momentary efficiency is alsocompared with the traditional formula.

关键词： D'Alembert-Lagrange equation Involutes gear Momentary efficiency

Research on heart sound identification technology

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science china(Information sciences) 2012年第2期55卷 281-292页

作者： CHENG XieFeng1,3.MA Yong2,LIU Chen1,ZHANG XueJun1 & GUO YuFeng11School of Electronic science and Engineering,nanjing University of Posts and Telecommunications,nanjing 210003.{3. 2School of computer science and technology,nanjing University of science and technology,nanjing 210094,{3. 3.ey Lab of Broudbard Wireless Communication and Sensor Network technology(nanjing University of Posts and Telecommunications),Ministry of Education,nanjing 210094,{3. 1. School of Electronic science and Engineering Nanjing University of Posts and Telecommunications Nanjing 210003 China3. Ministry of Education Key Lab of Broudbard Wireless Communication and Sensor Network Technology (Nanjing University of Posts and Telecommunications) Nanjing 210094 China2. School of Computer Science and Technology Nanjing University of Science and Technology Nanjing 210094 China

In this article,both the basic principles and the experimental methods of identity recognition technology based on heart sounds are ***,the characteristics of heart sounds and the feasibility of heart sounds as a biometric were analyzed.A synthetic model of heart sounds was then developed based on a family of wavelets;Finally,the characteristic parameters of heart sounds were extracted by using the heart sounds linear band frequency cepstra(HS-LBFC)with a specified configuration,and the similarity distance was adopted for heart sound *** highlight the difference in two heart sound signals between the time and frequency domains,a construction method of the heart sound wavelet,a calculation method of the parameters of a synthetic model,selection of the characteristic parameters of heart sounds and the corresponding data processing technology were *** experimental results showed that the proposed method exhibited excellent performance and practicability.

关键词： biometric wavelet family of heart sounds synthetic model of heart sounds heart sounds linear band frequency cepstra(HS-LBFC)

Synthesis and Lubrication of Phosphorylcholine Derivative

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Journal of Bionic Engineering 2010年第3期7卷 254-258页

作者： Zhenliang Qiao~1, Dangsheng Xiong~1, Lude Lu~2, Pengju Jiang~2 1. department of Materials science and Engineering, nanjing University of science and technology, nanjing 210094, P.R. china 2. School of Chemical Engineering, nanjing University of science and technology, nanjing 210094, P. R. china [a] department of Materials science Engineering Nanjing University of Science technology Nanjing 210094 P.R. China [b] School of Chemical Engineering Nanjing University of Science technology Nanjing 210094 P. R. China

The monomer of phosphorylcholine derivative, O-(5-（2-methacryloxy）-3. 3.dimethyl-3.azapentyl)-O’-（ω-hydroxy-octyl）-phosphatequaternary ammonium salt, was designed and synthesized successfully. It was characterized by the spectra ofHNMR and Mass spectra （ESI+）, and every signal was assigned. Then the lubricating characteristics of the phosphorylcholinederivative were investigated on the tribological setup of ball-oh-flat. The Ultra-High Molecular Weight Polyethylene（UHMWPE） flat was rotated against a stainless steel ball with 6 mm diameter. The load was 2.3.N, which corresponded to amaximal Hertz contact pressure of 29 MPa. Water, phosphorylcholine derivative, and Acrylic Acid （AA） solution were used aslubricants, respectively. Compared with AA, the phosphorylcholine derivative shows significant lubrication. It can be stronglyhydrated under water due to the charged segment in chemical structure. The thick water layers within the chains serves asboundary lubricants, and this is thought to be the molecular origins of lubricating behavior.

关键词： artificial joint articular cartilage molecular lubrication mechanism phosphorylcholine synthesis UHMWPE