查询词典 finite dimensional operator

It is shown that, any reprersentation finite special biserial algebra has a Groebner basis theory, and a finite-dimensional basic algebra over an algebraically closed field is representation finite if and only if every module over it has a right Groebner basis theory.

证明了表示有限特殊双列代数有Groebner基，从而扩大了Groebner基理论的应用范围；证明了一个代数封闭域上的有限维代数是表示有限特殊双列代数当且仅当其上每个右模都有右Groebner基理论，从而扩大了右Groebner基理论的应用范围。

On the basis of experimental research, this thesis applies 2-dimensional non-linear finite element method to the analysis of transient temperature field on the section by means of relatively high precision triangular element of six joints. When the temperature field is analyzed, finite element reseaus are divided in space field and finite difference reseaus are divided in time field, and then the program is compiled. The computing results are in good agreement with the test data. It indicates that the program is stable and precise.

在试验研究的基础上，本文采用精度较高的三角形六结点单元对构件截面二维非线性瞬态温度场进行了有限元分析，即在空间域内采用有限元网格划分，在时间域内采用有限差分网格划分，据此编制了计算程序，计算结果与试验数据符合较好，程序稳定性好，精度满足要求。

The book covers one-, two- and three dimensional problems which are solved by using exact and approximate analytical methods and numerical methods such as: the finite difference method, the finite volume method, the finite element method and the boundary method.

书中涵盖一，二和三是利用精确和近似分析方法和数值方法，如：有限差分法求解二维问题，有限体积法，有限元法和边界法。

This paper makes a three-dimensional model for QCM and analyzes directly the coupled phenomenon of the structural and electric fields of QCM with finite element analysis software ANSYS10.0. Through analyzing the convergence of the resonant frequency of QCM, the correctness of the finite element analysis is proved. The influence of different sizes of electrode on vibration of QCM and an optimal size of electrode is discovered, namely thickness of 100 nm and radius of 3 mm. The design of mesa on crystal plate is provided to solve the problem that the energy trapping is not good enough. This design proves valid based on finite element calculation and an optimal size of the mesa is given, namely height of 9.8 μm.

基于有限元分析软件ANSYS10.0对石英晶体微天平进行三维建模，验证了建模的正确性，并对不同电极结构尺寸进行仿真计算，对出现的耦合情况进行了分析，通过实验结果对比，提出较佳电极尺寸结构为厚度100 nm，半径3 mm；为解决金电极能陷效应不够理想的问题，提出在晶片上下表面筑平台的设计，有限元计算结果表明此设计能改善电极区的能陷效应，并且较佳平台高度为9.8μm。

This paper is based on the former research taking the No.1 Tong-Lv Bridge as an example; the large universal finite element program Midas/Civil is adopted, a three-dimensional finite element model is established. The static performance, the comparative analysis of influence surfaces, the experimental study and the analysis of a local finite element model of the new style three-span continuous through type bow-string arch bridge is made. With these studies, this paper is aimed at revealing the performance of this kind of construction.

本文在前人研究的基础上，以通吕一号桥为背景，采用空间有限元法对结构形式新颖的三跨连续下承式系杆拱桥的静力性能、影响面比较分析、实桥荷载试验、局部节点分析等进行研究，旨在深入理解该结构形式桥梁的力学性能，为今后相同结构体系桥梁的结构分析提供可以参考的建议。

In studies of interaction among pile, platform that above it and surrounding soil, this paper employ the concept of plate element to simulate the loading character of platform, and employ the concept of solid element to simulate the character of pile and soil, using the finite element method after understanding the geometry properties of pile, soil and the platform. Analyzing the loading properties of the three entities above and their deformation, this paper also employ a special element, Penalty Element. The introduction of penalty element of this kind has served to guarantee the join harmony of displacement between solid element and plate element, thereby effectively resolving the join problem between platforms, pile that support it and surrounding soil.Considering significant property difference between pile material and its surrounding soil, there may be much shear stress on their contact interface produced under vertical load, thus causing displacement or fission. Therefore it is necessary to adopt one special constitutive law of this kind of contact interface, which can reflect its feature of loading and deformation thoroughly. On the basis of the deformation feature and constitutive laws of some contact interface obtained by Zhang Dongji and people concerned through some single-shear experiments on contact interface between structure and soil, this paper employ one pile-soil three-dimensional constant thickness contact interface model to simulate the " slide" taken place on the interface between pile and its surrounding soil. With this kind model, this paper has also created one finite element model, which can be applied to perform finite element calculation and analyze the pile-loading feature, and deduced its element stiffness matrix.

在承台-桩-土共同作用中，考虑桩与承台的几何特性，采用有限元方法，用实体单元模拟桩土，用板单元模拟承台，更具体地分析桩和承台的受力特性和变形，而且还采用罚单元—既实体单元与板单元之间连接必须满足变形协调条件，来有效地解决了承台与桩土的连接问题，且在桩土共同作用中，由于桩体结构的材料性能与周围土层性质相差较大，在竖向荷载下有可能在其接触面上产生较大的剪应力从而导致错动或开裂，因此，为了充分反映桩土接触面上的受力及变形特征，应采用一种桩土接触面特有的本构关系，即利用张冬霁等人关于结构与土体接触面单剪试验所得到的接触面变形特征及其本构关系，引入桩-土三维等厚度接触单元来模拟桩与桩侧土之间的&滑移&，在此基础上建立可用于桩基承载性状分析的有限元计算单元模型，并推导出了各单元的刚度矩阵。

In the representation theory of finite-dimensional algebras, combinatorial tools as quivers and their representations provide effective method in computing Hochschild homology and cohomology groups of finite-dimensional algebras.

代数表示论中的组合工具—箭图及其表示的发展和应用，为计算有限维代数的Hochschild同调群与上同调群提供了有效的方法。

On the other hand, Let M~n be an z-dimensional complete noncompactoriented submanifold with finite total curvature in an-dimensional simplyconnected space form F~ of constant curvature c. In this thesis, we provethat if M satisfies one of the following: n≥3, c=0 and integral from n=M H~n＜∞;n≥5, c=-1 and H＜1-2/n~(1/2); n≥3, c=1 and H is bounded, where Hdenotes the mean curvature of M. then the dimension of the space of L~2 harmonic1-forms on M is finite.

本文还证明：若具常曲率c的完备单连通空间型F~中具有有限全曲率的n维完备非紧可定向子流形M满足下面条件之一：n≥3，c=0且integral from n=M H~n＜∞；n≥5，c=-1且H＜1-2/n~(1/2；n≥3，c=1且H有界的，则M上L~2调和1-形式空间的维数是有限的，这里H为M的平均曲率。

The latter is essentially derived from the geometric realization of Happels triangulated equivalence between stable module category of repetitive algebra and bounded derived category of finite dimensional algebra. In terms of this realization, we deduce that the Lie algebra realized by derived category of a finite dimensional algebra is isomorphic to the Lie algebra realized by stable module category of the corresponding repetitive algebra.

后者本质上是Happel关于重复代数的稳定模范畴和导出范畴的三角等价的一个几何实现及其应用，使用这种几何实现，我们可以证明在重复代数的稳定模范畴上定义的李代数同构于相应的导出范畴上实现的李代数。

Secondly, the gun barrel temperature field is solved by two-dimensional and one-dimensional heat conduction model with finite element method and finite difference scheme respectively.

其次通过对身管二维轴对称传热模型和一维径向传热模型的数值计算，研究了身管固壁的传热问题。二维轴对称传热计算采用了有限单元法，一维径向传热计算采用了有限差分法。

Through comparing with the results by simulation to study the effects of theprojectile"s final velocity, the angle of rotation and the ballistic trajectory"s migration withdifferent projectile"s rotating speeds, different target"s moving speeds and differentpenetration angles.

通过比较数值模拟的结果来研究不同弹头转速、目标速度、侵彻角对侵彻过程中弹头最终速度、翻转角度和弹道偏移的影响。

I love stationery and all the accoutrement of writing.

我爱文具以及所有的书写的工具装备。