检索结果-南通市图书馆

Application　of　a　Double－Wollaston－prism　Laser　Differential　Interferometer　in　Plasma　Focus

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Lasers 1996年第5期B5卷 461-466页

作者： LU Mingfang YANG Tsinchi HAN Min (tsinghua university, beijing 100084, china) tsinghua Univ Beijing China

ＡｐｐｌｉｃａｔｉｏｎｏｆａＤｏｕｂｌｅ－Ｗｏｌｌａｓｔｏｎ－ｐｒｉｓｍＬａｓｅｒＤｉｆｆｅｒｅｎｔｉａｌＩｎｔｅｒｆｅｒｏｍｅｔｅｒｉｎＰｌａｓｍａＦｏｃｕｓＬＵＭｉｎｇｆａｎｇ；ＹＡＮＧＴｓｉｎｃｈｉ；ＨＡＮＭｉ... 详细信息

ＡｐｐｌｉｃａｔｉｏｎｏｆａＤｏｕｂｌｅ－Ｗｏｌｌａｓｔｏｎ－ｐｒｉｓｍＬａｓｅｒＤｉｆｆｅｒｅｎｔｉａｌＩｎｔｅｒｆｅｒｏｍｅｔｅｒｉｎＰｌａｓｍａＦｏｃｕｓＬＵＭｉｎｇｆａｎｇ；ＹＡＮＧＴｓｉｎｃｈｉ；ＨＡＮＭｉｎ（ＴｓｉｎｇｈｕａＵｎｉｖｅｒｓ...

关键词： laser differential interferometry plasma focus

On mean curvatures in submanifolds geometry

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 Mathematics 2008年第6期51卷 1127-1134页

作者： GE JianQuan Department of Mathematical Sciences,tsinghua university,beijing 100084,china Department of Mathematical Sciences Tsinghua University Beijing 100084 China

By using moving frame theory,first we introduce 2p-th mean curvatures and(2p+1)-th mean curvature vector fields for a *** then give an integral expression of them that characterizes them as mean values of symmetric functions of principle *** we apply it to derive directly the celebrated Weyl-Gray tube formula in terms of integrals of the 2p-th mean curvatures and some Minkowski-type integral formulas.

关键词： moving frame mean curvature tube 53.07 53.42

On fixed-points and singular values of transcendental meromorphic functions

在线全文

学校读者我要写书评

暂无评论

Science china Mathematics 2010年第3期53卷 887-894页

作者： ZHENG JianHua Department of Mathematical Sciences, tsinghua university, beijing 100084, china 1. Department of Mathematical Sciences Tsinghua University Beijing 100084 China

In this paper we make a further discussion of a relationship between the number of fixed-points and distribution of singular values along the round annuli centered at the origin of a transcendental meromorphic function. To attain our purpose we first establish a fundamental inequality for the modulus of derivative of a holomorphic covering mapping whose image is an annulus by virtue of the hyperbolic metric. The inequality is of independent significance. We make a simple survey on some domain constants for hyperbolic domains.

关键词： meromorphic functions fixed points singular points hyperbolic metric covering mapping

GENERATION AND APPLICATION OF VARIATIONAL GEOMETRIC CONSTRAINTS NETWORK BASED ON ISO'S FEATURE

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Mechanical Engineering 2002年第4期15卷 319-323页

作者： Hu JieState CIMS Engineering Research center, tsinghua university, beijing 100084, {3.Wu Zhaotong Zhejiang university State CIMS Engineering Research center Tsinghua University Beijing 100084 China

The concept of variantional geometric constraints network is presented. Basedon ISO's feature, three kinds of variational geometric constraints are defined. The concepts ofmate tree (MT) and loop circuit (LC) are presented. The generation method of well-constrainedvariational geometric constraints network (VGCN) is studied. The network can be applied ingeneration of well-constrained tolerance types and tolerance chains. A simple example is analyzed toshow the scheme to be effective.

关键词： ISO's feature variational geometric constraint tolerance

On States of Total Weighted Occupation Times for Superdiffusions

在线全文

学校读者我要写书评

暂无评论

Acta Mathematica Sinica,English Series 2002年第1期18卷 69-78页

作者： REN Yan Xia center for Advanced Study. tsinghua university. beijing 100084. P. R. {3. center for Advanced Study Tsinghua University Beijing P. R. China

Suppose X is a superdiffusion in R^d with general branching mechanism ￠. and Y_(D) denotes the total weighted occupation time of X in a bounded smooth domain D. We discuss the conditions on ψ to guarantee that Y_(D) has absolutey continuous states. And for particular ψ(z) = z^(l+, 02 + 2/B. Y_^(D) is absolutely continuous with respect to the Lebesgue measure in D. whereas in the case d>2 + 2/B. it is singular. As we know the absolute continuity and singularity of Y_(D have not been discussed before.

关键词： Total weighted occupation time Superdiffusion Absolutely continuous state Singular states

Scheduling of Development Projects with Uncertain Iterations

在线全文

学校读者我要写书评

暂无评论

Journal of Systems Engineering and Electronics 2001年第2期12卷 82-86页

作者： Yan Jihong & Wu Cheng National CIMS Engineering Research center, tsinghua university, beijing 100084, P R. {3. National CIMS Engineering Research center Tsinghua University Beijing 100084 P. R. China

This paper studies the scheduling of design projects in concurrent development process with uncertain number of feedback revisions. An optimization based methodology that combines heuristic algorithm, artificial intelligence (fuzzy, genetic algorithm) and scheduling theory is developed. In the algorithm, weighting values of some key factors are defined by genetic algorithm. In addition, fuzzy logic is used to decide the ability coefficients of different roles taken by designers. Moreover, the process of pre-release and feedback revision is realized. Simulation example is a fraction of practical development project, and satisfied results are obtained.

关键词： Concurrent engineering Product development process Optimization scheduling.

RESEARCH ON PRODUCT INNOVATION DESIGN IN VIRTUAL PRODUCT DEVELOPMENT

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Mechanical Engineering 2002年第4期15卷 353-359页

作者： Wu Qunbo Zhang Linxuan Xiao Tianyuan Long Xinghai State CIMS Engineering Research center, tsinghua university, beijing 100084, {3. State CIMS Engineering Research center Tsinghua University Beijing 100084 China

An integrated template of virtual product development alters primarilysequential tradition mode of product life cycle. The template integrates all processes of productdevelopment using digital modem. An environment of virtual product development provides productdevelopment environment of integration, communion, network, concurrent and collaboration. Combiningdevelopment of new rapier loom, an innovated design process is researched in virtual productdevelopment, which consists three portions: constructing an integration development environment,innovation design and manufacturing simulation. The innovated design process realizes reversedesign, mechanism concept design, structural design and analysis, performance analysis andmanufacturing process simulation of virtual product, which can enhance greatly product performanceand reduce cost and development cycle of new product.

关键词： virtual product development innovation design product data management

Calculation of light emission in sonoluminescence

在线全文

学校读者我要写书评

暂无评论

Science china(Physics,Mechanics & Astronomy) 2009年第4期52卷 593-601页

作者： LI ChaoHui1 & AN Yu1,2 1 Department of Physics,tsinghua university,beijing 100084,china 2 Institute of Acoustics,Chinese Academy of Sciences,{3. 100190,china Department of Physics Tsinghua University Beijing 100084 China Institute of Acoustics Chinese Academy of Sciences Beijing 100190 China

We modify a uniform model of single bubble sonoluminescence,in which heat diffusion,water vapor diffusion and chemical reactions are included to describe the bubble dynamics,and the processes of electron-atom bremsstrahlung,electron-ion bremsstrahlung and recombination radiation,radiative attachment of electrons to atoms and molecules,line emissions of OH radicals and Na atoms are taken into account to calculate the light emission. With this model,we compute the light pulse width,the photon number per flash,the continuum and line spectra and the gas species as the products of chemical reactions,and try to compare with all the experimental data available. We obtain good agreement with the observations of Ar and Xe bubbles in many cases,but fail to match the experimental data of the photon number per flash. We also find that for He bubble the computed photon number is always too small to interpret the observations.

关键词： sonoluminescence bremsstrahlung radiative attachment line spectrum collision broadening

Fabrication of Grain-oriented (Bi,Pb)_2Sr_2Ca_2Cu_3._x Superconducting Tapes Using Magnetic Field and Vibration Technique

在线全文

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 1998年第1期14卷 86-88页

作者： Yanwei MA and Xianjin WANG (Dept. of Metal Forming, university of Science and Technology beijing, beijing 100083. {3.)Zutang WANG (tsinghua university, beijing 100084, {3.) Univ Sci & Technol beijing Dept Met Forming Beijing 100083 Peoples R China Tsing Hua Univ Beijing 100084 Peoples R China

Highly textured (Bi,Pb)2Sr2Ca2Cu3.x superconducting tapes have been fabricated by means of magnetic-field and vibration technique. This method is an effective way of improving the degree of grain alignment and density of oxide core in tapes after heat treatment and pressing *** of above 20% was increased than that without treatment.

关键词： Bi,Pb Pb Sr Fabrication of Grain-oriented x Superconducting Tapes Using Magnetic Field and Vibration Technique Ca Cu