检索结果-南通市图书馆

GLOBAL EXISTENCE AND BLOW-UP OF SOLUTIONS FOR GENERALIZED POCHHAMMER-CHREE EQUATIONS

在线全文

学校读者我要写书评

暂无评论

Acta Mathematica Scientia 2010年第5期30卷 1793-1807页

作者：徐润章刘亚成 college of science Harbin Engineering University

In this article, we study the initial boundary value problem of generalized Pochhammer-Chree equation utt-uxx-uxxt-uxxtt=f（u）xx,x∈Ω,t〉0,u（x,0）=u0（x）,ut（x,0）=u1（x）,x∈Ω,u（0,t）=u（1,t）=0,t≥0, where Ω = （0, 1）. First, we obtain the existence of local Wkp solutions. Then, we prove that, if f（s） ∈ Ck＋1（R） is nondecreasing, f（0） = 0 and ｜f（u）｜ ≤ C1｜u｜∫0uf（s）ds ＋ C2. u0（x）,u1（x） ∈ WkP（Ω） ∩ W01,P（Ω）, k≥ 1, 1 〈 p≤ ∞, then for any T 〉 0 the problem admits a unique solution u（x, t） ∈ W2.∞（0, T; WkP（Ω） ∩ W01,P（Ω））. Finally, the finite time blow-up of solutions and global Wkp solution of generalized IMBo equations are discussed.

关键词： Pochhammer-Chree equations initial boundary value problem Wkp solu-tion global existence blow-up

Numerical Simulation and Assessment of Self-induced Tensile Stresses in Steel Ring Restrained Concrete

在线全文

学校读者我要写书评

暂无评论

Journal of Wuhan university of Technology(Materials science) 2010年第3期25卷 530-533页

作者：马新伟 Department of Civil engineering Harbin Institute of Technology

For a better understanding of the strains and stresses,numerical simulation was conducted by using ANSYS under the assumption of absolute bond between the steel and *** results show that the stresses and strains in such concrete and steel rings are uneven;the curves of strains and stresses change gradually around the *** ease numerical computation,the mechanical system was simplified under the assumptions of synchronous deformation and uniform strains and *** results of the numerical simulation and simplified stress calculation can match almost *** means that the simplified mechanical model can be used in stress and visco-elastic behavior quantification.

关键词： restrained shrinkage numerical simulation model simplification

Modelling Immune System:Principles,Models,Analysis and Perspectives

在线全文

学校读者我要写书评

暂无评论

Journal of Bionic engineering 2009年第1期6卷 77-85页

作者： Xiang-hua Li~1, Zheng-xuan Wang~1, Tian-yang Lu~2. Xiang-jiu Che~11. college of Computer science and Technology, Jilin {2., Changchun 130012. P. R. China2. college of Computer science and Technology, harbin engineering university, harbin 150001, P. R. China [a]college of Computer science and Technology Jilin University Changchun 130012 P. R. China [b]College of Computer Science and Technology Harbin Engineering University Harbin 150001 P. R. China

The biological immune system is a complex adaptive *** are lots of benefits for building the model of the immune *** biological researchers,they can test some hypotheses about the infection process or simulate the responses of some *** computer researchers,they can build distributed,robust and fault tolerant networks inspired by the functions of the immune *** paper provides a comprehensive survey of the literatures on modelling the immune *** the methodology perspective,the paper compares and analyzes the existing approaches and models,and also demonstrates the focusing research effort on the future immune models in the next few years.

关键词： immune system modelling agent-based simulation complex adaptive system (CAS) HIV

Formation,thermal stability and mechanical properties of Ti_(42.5)Zr_(7.5)Cu_(40)Ni_5Sn_5 bulk metallic glass

在线全文

学校读者我要写书评

暂无评论

science China(Physics,Mechanics & Astronomy) 2008年第4期51卷 372-378页

作者： HUANG YongJiang,SHEN Jun & SUN JianFei School of Materials science and engineering,{2. Institute of Technology,{2. 150001,China 1. School of Materials science and engineering Harbin Institute of Technology Harbin 150001 China

Ti42.5Zr7.5Cu40Ni5Sn5 bulk metallic glass with a critical diameter of 4 mm was fabri-cated by the conventional copper mould casting method. The supercooled liquid region ΔTx,reduced glass transition temperature Trg,γ parameter,and δparameter of the alloy were measured to be 63.9 K,0.561,0.393,and 1.400,respectively,im-plying that the alloy has an excellent glass-forming ability. The bulk metallic glass exhibits high compressive fracture strength of 2.62.MPa with distinct plastic strain of 0.9%. The fracture surface consists mainly of vein-like patterns,typical of bulk glassy alloys.

关键词： amorphous alloy mechanical properties thermal stability glass-forming ability

Reliability analysis of ship structure system with multi-defects

在线全文

学校读者我要写书评

暂无评论

science China(Physics,Mechanics & Astronomy) 2010年第11期53卷 2113-2124页

作者： AN Hai 1,AN WeiGang 1 & ZHAO WeiTao 2.1 School of Aerospace and Civil engineering,harbin engineering university,harbin 150001,China 2.School of Aeronautics and Astronautics,Shenyang Institute of Aeronautical engineering,Shenyang 110034,China 1. School of Aerospace and Civil engineering Harbin Engineering University Harbin 150001 China2. School of Aeronautics and Astronautics Shenyang Institute of Aeronautical Engineering Shenyang 110034 China

This paper analyzes the influence of multi-defects including the initial distortions,welding residual stresses,cracks and local dents on the ultimate strength of the plate element,and has worked out expressions of reliability calculation and sensitivity analysis of the plate *** analysis is made for the system with multi-defects plate *** mechanism,failure paths and the calculating approach to global reliability index are also worked *** plate elements with multi-defects fail,the formula of reverse node forces which affect the residual structure is deduced,so are the sensitivity expressions of the system reliability *** ensures calculating accuracy and rationality for reliability analysis,and makes it convenient to find weakness plate elements which affect the reliability of the structure ***,for the validity of the approach proposed,we take the numerical example of a ship cabin to compare and contrast the reliability and the sensitivity analysis of the structure system with multi-defects with those of the structure system with no *** approach has implications for the structure design,rational maintenance and renewing strategy.

关键词： initial distortions welding residual stresses cracks and local defects ultimate strength reverse node forces sensitivity expression reliability analysis

An Application of the Modified Shear Lag Model to Study the Influence of Thermal Residual Stresses on the Stiffness and Yield Strength of Short Fiber Reinforced Metal Matrix Composites

在线全文

学校读者我要写书评

暂无评论

Journal of Materials science & Technology 1999年第3期15卷 213-221页

作者： Zhonghao JIANG and Jianshe LIAN(Dept. of Materials science and engineering, Jilin {2. of Technology, Changchun 13002., China)Shangli DONG and Dezhuang YANG(School of Materials science and engineering, harbin Institute of Technology, harbin 150001, Dept. of Materials science and engineering Jilin University of Technology Changchun 130025 China School of Materials science and engineering Harbin Institute of Technology Harbin 150001 China

The modified shear lag model proposed recently was applied to calculate thermal residual stresses and subsequent stress distributions under tensile and compressive loadings. The expressions for the elastic moduli and the yield strengths under tensile and compressive loadings were derived which take account of thermal residual stresses. The asymmetries in the elastic modulus and the yield strength were interpreted using the derived expressions and the obtained results of the stress calculations. The model predictions have exhibited good agreements with the experimental results and also with the other theoretical predictions

关键词： ab Figure An Application of the Modified Shear Lag Model to Study the Influence of Thermal Residual Stresses on the Stiffness and Yield Strength of Short Fiber Reinforced Metal Matrix Composites

Detecting malignant patients via modified boosted tree

在线全文

学校读者我要写书评

暂无评论

science China(Information sciences) 2010年第7期53卷 1369-1378页

作者： DONG CaiLing1, YIN YiLong1 & YANG XiuKun2.1School of Computer science and Technology, Shandong university, Jinan 2.0101, China 2.2. of Information and Communication, harbin engineering university, harbin 150001, China 1. School of Computer science and Technology Shandong University Jinan 250101 China2. College of Information and Communication Harbin Engineering University Harbin 150001 China

As one of the most effective measures to extract useful information from medical database and provide scientific decision-making for diagnosis and treatment of diseases, medical data mining has become an increasingly hot topic in the last few years. Some of the intrinsic characteristics of medical databases, such as the huge volume and imbalanced samples as well as stringent performance standards, make this mining process particularly challenging. By elaborating various challenges existing in Task 1 of KDD Cup 2.08 competition, this paper analyzes some potential solutions to these problems and presents a modified boosted tree as the final classification model. This model ranked the fourth among all the solutions to Task 1. We hope that our analysis and solutions to these challenges would contribute to the development of medical data mining applications.

关键词： classification boosted tree multiple instances scoring Real AdaBoost breast cancer detection medical data mining

An Expert System in FRP Composite Material Design

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Journal of Materials science & Technology 2001年第5期17卷 556-560页

作者： Qingfen LI, Zhaoxia CUI and Weimin WANG college of Mechanical & Electrical engineering,{2., harbin 150001, China Jianhua GAO Department of Mechanical engineering, Shanghai Jiao Tong university, Shanghai 2.0030, China harbin Engn Univ Coll Mech & Elect Engn Harbin 150001 Peoples R China Shanghai Jiao Tong Univ Dept Mech Engn Shanghai 200030 Peoples R China

An expert system prototype for fibre-reinforced plastic matrix (FRP) composite material design, ESFRP, has been developed. The system consists of seven main functional parts: a general inference engine, a set of knowledge bases, a material properties algorithm base, an explanation engine, various data bases, several function models and the user interface. The ESFRP can simulate human experts to make design scheme for fibre-reinforced plastics design, FRP layered plates design and FRP typical engineering components design. It can also predict the material properties and make strength analysis according to the micro and macro mechanics of composite materials. A satisfied result can be gained through the reiterative design.

关键词： An Expert System in FRP Composite Material Design FRP

Enhancing the capacitances of electric double layer capacitors based on carbon nanotube electrodes by carbon dioxide activation and acid oxidization

在线全文

学校读者我要写书评

暂无评论

science China(Technological sciences) 2010年第5期53卷 1234-1239页

作者： LI ChenSha1,2.QIAO YingJie1,WU JianJun2.WANG DaZhi2.& YUAN DianBo2.1 Department of Materials science,harbin {2. university,harbin 150001,China 2.Department of Mechanical {2.,Tsinghua university,Beijing 100084,China 1. Department of Materials science Harbin Engineering University Harbin 150001 China2. Department of Mechanical Engineering Tsinghua University Beijing 100084 China

Polarizable electrodes of electric double layer capacitors(EDLCs) were made from carbon nanotubes(CNTs).Effect of carbon dioxide activation together with acid oxidation for the electrodes on the characteristics and performances of electrodes and EDLCs was *** dioxide activation changed the microstructure of the electrodes,increased the effective surface area of CNTs and optimized the distribution of apertures of the *** oxidization modified the surface characteristics of *** on the polarizable electrodes treated by carbon dioxide activation and acid oxidization,the performances of EDLCs were greatly *** specific capacitance of the electrodes with organic electrolyte was increased from 2..8 F/g to 60.4 F/g.

关键词： carbon nanotube electric double layer capacitor scan electron microscopy