检索结果-南通市图书馆

OPTIMAL CONTROL APPLIED IN AUTOMATIC CLUTCH ENGAGEMENTS OF VEHICLES

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Mechanical Engineering 2004年第2期17卷 280-283页

作者： Sun Chengshun Zhang Jianwu School of Mechanical and Power Engineering,shanghai jiaotong {2.,shanghai 2.0030, china School of Mechanical and Power Engineering Shanghai Jiaotong University Shanghai 200030 China department of Science and Technology Studies University College London WC1E 6BT UK

Start-up working condition is the key to the research of optimal engagementof automatic clutch for AMT. In order to guarantee an ideal dynamic performance of the clutchengagement, an optimal controller is designed by considering throttle angle, engine speed, gearratio, vehicle acceleration and road condition. The minimum value principle is also introduced toachieve an optimal dynamic performance of the nonlinear system compromised in friction plate wearand vehicle drive quality. The optimal trajectory of the clutch engagement can be described in theform of explicit and analytical expressions and characterized by the deterministic and accuratecontrol strategy in stead of indeterministic and soft control techniques which need thousands ofexperiments. For validation of the controller, test work is carried out for the automated clutchengagements in a commercial car with an traditional mechanical transmission, a hydraulic actuator, agroup of sensors and a portable computer system. It is shown through experiments that dynamicbehaviors of the clutch engagement operated by the optimal control are more effective and efficientthan those by fuzzy control.

关键词： Automatic clutch Optimal control Nonlinear system dynamics

Eigenvalues of Large Matrices

在线全文

学校读者我要写书评

暂无评论

原子核物理评论 2009年第S1期26卷 165-167页

作者： ZHAO Yu-min1,2.(1 department of physics,{2., shanghai 2.02.0,china 2.Center of Theoretical Nuclear physics, National Laboratory of Heavy Ion Research Facility in Lanzhou, Lanzhou 730000, china)

We recently performed a series of improvement on evaluation of eigenvalues without complicated iterations. In this work we first discuss evaluation of the lowest eigenvalue for given systems,by which one conveniently obtains the value of the lowest eigenvalue based on the dimension and width of given matrix. We also discuss a strong correlation between eigenvalues and diagonal matrix elements for large matrices,by which one is able to predict eigenvalues approximately without iterations.

关键词： eigenvalue large matrix correlation

The multi-soliton solutions of the CH-γ equation

在线全文

学校读者我要写书评

暂无评论

Science china Mathematics 2008年第2期51卷 314-320页

作者： CHEN ChunLi~(1+) LI YiShen~2.ZHANG JinE~3 1 department of Mathematics,shanghai {2. university,shanghai 2.02.0,china 2.department of Mathematics,university of Science and Technology of china,Hefei 2.002.,china 3 SB and SEF,university of Hong Kong,Pokfulam Road,Hong Kong,china department of Mathematics Shanghai Jiaotong University Shanghai 200240 China department of Mathematics University of Science Technology of china Hefei 230026 China SB SEF University of Hong Kong Pokfulam Road Hong Kong China

This paper solves the integrable CH-γequation for analytical multiple soliton solutions with the Darboux transformation *** properties of the soliton solutions are different from the CH equation.

关键词： CH-γ equation multi-soliton solutions Darboux transformation 35Q35 35Q51

Blake-Wilson,Johnson & Menezes protocol revisited

在线全文

学校读者我要写书评

暂无评论

Science china(Information Sciences) 2011年第7期54卷 1365-1374页

作者： HUANG Hai 1,2.& CAO ZhenFu 1 1 department of Computer Science and Engineering,shanghai {2. university,shanghai 2.02.0,china 2.Division of Computer,Zhejiang Sci-Tech university,Xiasha Higher Education Zone,Hangzhou 310018,china 1. department of Computer Science and Engineering Shanghai Jiaotong University Shanghai 200240 China2. Division of Computer Zhejiang Sci-Tech University Xiasha Higher Education Zone Hangzhou 310018 China

In this paper,we investigate the famous Blake-Wilson,Johnson & Menezes (BJM) authenticated key exchange *** observe that the BJM model fails to model the adversary’s capability in the public setting *** modify the BJM model by providing it with a new Register query and a modified Corrupt *** way,we bring the BJM model further to ***,our modification has a significant impact on the security proof of the BJM ***,the security proofs using CDH assumption will no longer work in the modified BJM *** some modifications,we show that the BJM protocols are secure in the modified BJM model under the gap Diffie-Hellman assumption (GDH).

关键词： authenticated key exchange provable security BJM model gap Diffie-Hellman

Puncturing Period on the Performance of Punctured Turbo Codes

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Wuhan university Journal of Natural Sciences 2002年第3期7卷 319-322页

作者： Xu Heng\|ping, Pan Sheng, Zhao Xun, Rong Meng\|tian department of Electronic Engineering, shanghai jiaotong university,{2., shanghai, china shanghai jiaotong {2. Department of Electronic Engineering Shanghai Shanghai China (GRID:grid.16821.3c) (ISNI:***)

Puncturing is the predominant strategy to construct high code rate turbo codes. Puncturing period is a crucial parameter influencing the performance of punctured turbo codes (PTC). Here we developed a new puncturing scheme of turbo codes, with which the puncturing period on the performance of PTC is studied. Consequently, suggestions on selecting the puncturing period are proposed.

关键词： Key words puncturing period puncturing table AWGN turbo codes

s-ordering operator expansions of quantum-mechanical fundamental representations and their applications

在线全文

学校读者我要写书评

暂无评论

Science china(physics,Mechanics & Astronomy) 2011年第12期54卷 2150-2154页

作者： FAN HongYi 1,3 , XU YeJun 2.& YUAN HongChun 3,4 1 department of Materials Science and Engineering, university of Science and Technology of{2., Hefei 2.002.,{2. 2.department of physics Electronic and Engineering, Chizhou university, Chizhou 2.7000,{2. 3 department of physics, shanghai Jiao Tong university,{12.,{2. 4 College of Optoelectronic Engineering, Changzhou Institute of Technology, Changzhou 2.3002.{2. 1. department of Materials Science and Engineering University of Science and Technology of China Hefei 230026 China3. Department of Physics Shanghai Jiao Tong University Shanghai 200030 China2. Department of Physics Electronic and Engineering Chizhou University Chizhou 247000 China4. College of Optoelectronic Engineering Changzhou Institute of Technology Changzhou 213002 China

We show that the quantum-mechanical fundamental representations, say, the coordinate representation, the coherent state representation, the Fan-Klauder entangled state representation can be recast into s-ordering operator expansion, which is elegant in form and has many applications in deriving new operator identities. This demonstrates that Dirac's symbolic method can be merged into Newton-Leibniz integration theory in a broad way.

关键词： s-ordering operator expansion operator identities quantum mechanical representation

Beam Polarization Dependence of Diffraction Efficiency in Photorefractive LiNbO3 Crystal

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Lasers 2000年第5期9卷 62-68页

作者： YAN Xiaona 1 YAN Jinkui 1 YU Bingkun 1 LIU Liren 2.( 1 department of physics, {2. university, No.99 of Qixiang Road, {2. 2.0436, china 2.Information Optics Laboratory, {2. Institute of Optics and Fine Mechanics, The 上海大学上海中科院上海光学精密机械所信息光学开放实验室上海

In weak doped photorefractive LiNbO 3 crystal, the diffraction efficiency is highly relevant to the writing and reading beam polarizations. In this paper, based on dynamic coupled wave equations, we theoretically discuss the diffraction efficiency under four writing and reading polarization conditions, then reach the proven conclusion that with o polarized beams to write and with e polarized beam to readout, the diffraction is the largest.

关键词： defraction efficiency beam polarization refractive index

Structure analysis of ^(159)Sm and properties of odd-mass neutron-rich nuclei in mass-160 region

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Science china(physics,Mechanics & Astronomy) 2011年第S1期54卷 81-87页

作者： YANG YingChun1 & SUN Yang1,2.3 1 department of physics, {2. Jiao Tong university, {2. 2.02.0, china 2.nstitute of Modern physics, Chinese Academy of Sciences, Lanzhou 730000, china 3department of physics and Astronomy, university of Tennessee, Knoxville, Tennessee 37996, USA 1. department of physics Shanghai Jiao Tong University Shanghai 200240 China2. Institute of Modern Physics Chinese Academy of Sciences Lanzhou 730000 China3. Department of Physics and Astronomy University of Tennessee Knoxville Tennessee 37996 USA

Recent fission experiment data provide interesting structure information for neutron-rich nuclei in the mass A ～ 160 region. We apply the projected shell model to study the strongly-deformed, neutron-rich Sm isotopes. We perform calculations for rotational bands up to spin I = 2. (2./2. for even-even (odd-neutron) Sm isotopes, and analyze the band structure of low-lying states with quasiparticle excitations. Emphasis is given to rotational bands based on one-quasiparticle (1-qp) configurations in the odd-mass 159Sm. The 159 Sm result is discussed together with those of the even-even isotopes 158,160Sm. New bands in 159Sm based on neutron 1-qp 1/2.and 5/2. configurations are predicted. Electromagnetic transition probabilities are discussed.

关键词： projected shell model neutron-rich nuclei low-lying excitations isomeric states

Anticoagulation property and security of artificial heart valve material

在线全文

学校读者我要写书评

暂无评论

Science china(Technological Sciences) 2005年第2期48卷 145-162页

作者： WANG Xianghui1, , LIU Xianghuai1,2., 3, ZHANG Feng2. LI Changrong2. YU Liujiang2. ZHENG Zhihong2. WANG Xi2. JIANG Zhenbin4, CHEN Anqing4 & XU Jingfang3 1. department of physics, East{2. Normal university, shanghai 2.0062.{2. 2. Ion Beam Lab, shanghai Institute of Mini-system and information, Chinese Academy of Sciences,shanghai 2.0050,{2. 3. department of Electronics, School of Information Science and Technology, East{2. Normal Univer- sity, shanghai 2.0062.{2. 4. shanghai Cardiovascular Institute, Zhongshan Hospital, shanghai 2.0032.{2. 1. department of physics East China Normal University 200062 Shanghai China 2. Ion Beam Lab Shanghai Institute of Mini-system and information Chinese Academy of Sciences 200050 Shanghai China 3. department of Electronics School of Information Science and Technology East China Normal University 200062 Shanghai China 4. shanghai Cardiovascular Institute Zhongshan Hospital 200032 Shanghai China

Heart valve diseases threaten human health. One reliable way to save lives of such patients is to replace the pathologically changed heart valves by artificial ones. Over 2.million patients have received LTI-carbon heart valve’s implantation. However, the thrombosis after the implantation is one of the difficulties that need to be solved. In order to improve the blood compatibility and security of mechanical heart valves, ion beam technology was used to modify the surface properties of the materials. The investigation results have been summarized in this paper.

关键词： artificial heart valve, ion implantation, plasma immersed ion implantation, ion beam enhanced deposition.