检索结果-南通市图书馆

Science china Mathematics 2006年第5期49卷 620-625页

作者： HAI Jinke department of Mathematics, qingdao university, qingdao 266071, china College of mathematics ,Shandong university, Jinan 250100, china department of Mathematics Qingdao University Qingdao China College of mathematics Shandong University Jian China

Let π be a set of primes and G a π-separable group. Isaacs defines the Bπ characters, which can be viewed as the "π-modular" characters in G, such that the Bp′ characters form a set of canonical lifts for the p-modular characters. By using Isaacs' work, Slattery has developed some Brauer's ideals of p-blocks to the π-blocks of a finite π-separable group, generalizing Brauer's three main theorems to the π-blocks. In this paper, depending on Isaacs' and Slattery's work, we will extend the first main theorem for π-blocks.

关键词： π-block, π-separable group, π-regular classes, defect group.

On Browkin's conjecture about the elements of order five in K_2(Q)

在线全文

学校读者我要写书评

暂无评论

Science china Mathematics 2007年第1期50卷 116-120页

作者： Ke-jian XU department of Mathematics, qingdao university, qingdao 266071, china department of Mathematics Qingdao University Qingdao China

Based on the work of Lenstra, a succinct proof of Browkin’s conjecture about the elements of order five in K2(Q) is given.

关键词： K2 group cyclotomic polynomial lattice binary quartic form.

Study on the two and three-parameter working stability regions of 3Y-TZP suspension

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Science china(Technological Sciences) 2006年第5期49卷 547-568页

作者： chen Youqiang1, 2, ZHANG Xinni3, chen Sha’ou3 & QI Ping3 1. department of Chemistry, qingdao university, qingdao 266071, china 2. department of Chemistry, Tsinghua university, Beijing 100084, china 3. department of Physics, qingdao university, qingdao 266071, china department of Physics Qingdao University

We determined the variation tendency of viscosity (η) at various solids load- ing (α) for 3Y-TZP suspension as a function of dispersant concentration (Cw) using vis- cosity measurement, measured the diameter of particles as a function of Cw in very dilute suspension using light scattering method, and obtained the surface features of the sedi- ment of suspension with different Cw using SEM. We also discussed the influence of the microstructure of adsorbed polymer layers on particles and their interactions in the dis- persing medium on the stability of suspension. Then two different stable states and two different unstable states for 3Y-TZP suspension were given. Accordingly, the (Cw, η), (Cw, α), and (α, η) two-parameter, and (Cw, α, η) three-parameter stability maps were con- structed. Based on the DLVO theory calculations, the dispersant concentration, particle distance (r), and interparticle potential energy (VT) maps with various solids loading for 3Y-TZP aqueous suspension were also constructed. In (Cw, r) two-parameter coordinate system, the stable motion region map for particles was established. The Cw, α, and VT,max (the highest potential energy) surface of the potential barrier map was obtained through calculation and simulation on the basis of the surfaces of Cw, r, VT maps introduced above. The (Cw, α) two-parameter stability map was then obtained from the Cw, α, VT,max map. The results showed that this theoretical map can qualitatively prove the experimentally obtained results—the existence of different dispersed states of particles in suspension system and the variation tendency of suspension stability with changing each parame- ter—were reasonable.

关键词： 3Y-TZP, suspension, stability, DLVO theory, interparticle potential energy.

The Electrochemical Characteristics of Multilayer Assembly of Hemoglobin and Polystyrene Sulfonate at Self-assembled MonolayerSurface

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2000年第1期11卷 81-84页

作者： Hong SUN (department of Chemistry, Textile College, qingdao university, qingdao 266071) department of Chemistry Textile College Qingdao University Qingdao 266071 China

A multilayer film of hemoglobin (Hb) molecules and polyelectrolyte sulfonate were fabricated on a thiol self-assembled monolayers (SAMs) by electrostatic force. The Hb maintains electroactive property in the multilayer film, methylene blue (MB) incorporated into the multilayer can enhance the electron transfer rate between the Hb and the electrode surface.

关键词： multilayer film hemoglobin methylene blue

ON RAYleiGH QUOTIENT MATRICES: THEORY ANDAPPLICATIONS

在线全文

学校读者我要写书评

暂无评论

Journal of Computational Mathematics 1999年第6期17卷 629-638页

作者： Xin-guo Liu(department of Applied Mathematics Ocean university of qingdao, qingdao 266003, china) 青岛海洋大学应用数学系山东青岛 266003

Many authors have studied the Rayleigh quotient and Rayleigh quotient matrix. This paper consists of two parts. First, generalizations of some results on the Rayleigh quotient are proved. Second, we give some applicat... 详细信息

关键词： Rayleigh quotient matrix eigenvalue approximation

A NOTE ON THE BACKWARD ERRORS FOR INVERSE EIGENVALUE PROBLEMS

在线全文

学校读者我要写书评

暂无评论

Journal of Computational Mathematics 2003年第2期21卷 201-206页

作者： Xinguo Liu Zhengjian Bai (department of Mathematics, Ocean university of china, qingdao 266071) Departmenl of Mathematics Ocean University of China Qingdao 266071

In this note, we consider the backward errors for more general inverse eigenvalue problems by extending Sun's approach. The optimal backward errors are defined for diagonal-ization matrix inverse eigenvalue problem with respect to an approximate solution, and the upper and lower bounds are derived for the optimal backward errors. The results may be useful for testing the stability of practical algorithms.

关键词： Inverse eigenvalue problem Optimal backward error Upper bound Lower bound

Research on dual-stator winding multi-phase high-speed induction generator with rectifier load

在线全文

学校读者我要写书评

暂无评论

Science china(Technological Sciences) 2008年第6期51卷 683-692页

作者： WANG XiangHeng1 & WU XinZhen2 1 department of Electrical Engineering, Tsinghua university, Beijing 100084, china 2 department of Electrical Engineering, qingdao university, qingdao 266071, china department of Electrical Engineering Tsinghua University Beijing 100084 China department of Electrical Engineering Qingdao University Qingdao 266071 China

Based on analysis and calculation of the relation between current harmonics and MMF harmonics in the dual-stator winding multi-phase high-speed induction gen-erator with a rectifier load, a new idea, which divides the generator system into two sub-systems to be analyzed individually, is presented. For the sub-system of the 12-phase power winding with a rectifier load, the loop current method is used to establish network equation set in terms of the network graph theory. The numerical stability problem is solved by alternating use of fixed time-step and varied time-step, and the voltage and current with their fundamental components of the power winding are obtained. For the other sub-system of the induction generator with dual-stator winding and solid cage rotor, the electromagnetic field analysis method and the multi-variable optimization approach are combined to get the con-trol winding current and stator frequency. Calculated results well match experiment results, indicating that the new proposed method is of effectiveness and high ac-curacy.

关键词： dual-stator winding induction generator rectifier load MMF analysis loop current method finite element method optimization approach

The advancement of oscillation theory of functional differential equations

在线全文

学校读者我要写书评

暂无评论

Chinese Science Bulletin 1998年第12期43卷 974-982页

作者： ZHANG Binggen department of Applied Mathematics, Ocean university of qingdao, qingdao 266003, china department of Applied Mathematics Ocean University of Qingdao Qingdao China

The oscillation theory of functional differential equations (FDEs) is surveyed including (ⅰ) formulation of oscillation problems; (ⅱ) a brief history of the oscillation theory of FDEs; (ⅲ) main topics in the oscill... 详细信息

关键词： functional differential equations oscillation theory.

An Efficient Approach for Fuzzy Project Network Analysis

在线全文

学校读者我要写书评

暂无评论

Systems Science and Systems Engineering 2002年第1期11卷 83-89页

作者： HU Jing-song department of Management Science & Engineering, qingdao university, qingdao 266071,china department of Management Science & Engineering Qingdao University Qingdao 266071 China

In this paper we present two-level linear programming method for determining latest dates and slack times in project network models with triangular fuzzy number or trapezoidal fuzzy number. Compared with the well-known fuzzy network techniques in literature, the approach always produces the meaningful latest dates and slack times. Practically we have generalized critical path method by accepting imprecise, fuzzy data for the duration of the activities.

关键词： network analysis fuzzy equations linear programming