共查询到19条相似文献,搜索用时 140 毫秒
1.
2.
三维岩体移动分析的Fuzzy数学模型 总被引:1,自引:1,他引:0
李文秀 《数学的实践与认识》1991,(1)
本文是文献[1,2,3,4]的深入研究和初步完善.文中研究了 N 维 Fuzzy 概率理论在岩体力学学科中的进一步应用.根据实际岩土工程中的岩体移动观测资料,建立了岩体移动问题的三维 Fuzzy 数学模型,并通过工程实例的计算分析论证了该模型的适用性.从而基本解决了岩体力学学科内一直未能获得解决的金属矿岩体连续移动预计这一重要课题,在岩体力学领域形成了新的理论体系——Fuzzy 数学理论体系. 相似文献
3.
4.
St.Venant-Levy-Mises材料塑性力学的Lagrange形式 总被引:1,自引:0,他引:1
沈惠川 《数学物理学报(A辑)》2000,20(1):70-73
将St.Venant-Levy-Mises材料的塑性力学问题纳入Lagrange力学的理论体系,讨论了这一种材料的塑性力学三维问题,小挠度问题以及有限变形(大挠度)问题的基本微分方程。 相似文献
5.
6.
沈惠川 《数学物理学报(A辑)》1998,18(1):78-88
将弹性有限变形问题纳入Lagrange力学的理论体系中,并用经典力学中业已存在的Routh方法构建了有限变形平面应变问题和有限变形平面应力问题的基本微分方程,讨论了有限变形大挠度问题vonkarman方程中存在的矛盾进而提出了两种改进方案. 相似文献
7.
8.
《应用数学和力学》2012,(10):I0001-I0002
钱伟长(1912年10月9日-2010年7月30日) 今年10月9日,是本刊创办人钱伟长教授诞辰100周年。钱伟长教授是我国最杰出的、也是国际知名的力学和应用数学家之一。他在上世纪40年代关于弹性板壳内禀理论的工作,不仅统一了当时众说纷纭的各种板壳理论,同时也开创了理性力学的新领域。在40到50年代关于奇异摄动理论和弹性圆薄板大挠度问题的研究、60年代关于广义变分原理的研究,都是领一代风气之先的开创性工作。他不仅在应用数学和力学的各个方面作出了重要贡献,对中国力学事业发展所起的作用也是不可替代的,他是中国的第一个力学专业、第一个力学研究机构的创办人,是促进中国非线性力学发展的带头人,他被公认为中国当代力学的四位奠基人之一。 相似文献
9.
10.
11.
本文是文[1~4]的继续和升华.(1)在本文中,我们根据互补性原理,建立了耗散力学.它是与量子力学相对应的一种耗散理论.可以用这种理论来统一地处理非平衡态热力学和粘滞流体动力学问题,并可以用它来处理量子力学中各种耗散和不可逆的问题.耗散力学的基本方程是与Schr?dinger方程或Dirac方程相对应的一类本征值方程;(2)在本文中,我们将一些基本的非线性耗散型方程,特别是作为宏观非平衡态热力学和粘滞流体动力学基本方程的Navier-Stokes方程,统一地归结为耗散力学基本方程的可积性条件,从而为利用散射反演方法求它们的精确解扫平了道路. 相似文献
12.
E. Mamontov 《Mathematical and Computer Modelling》2009,49(7-8):1551-1562
The key model for particle populations in statistical mechanics is the Bogolyubov–Born–Green–Kirkwood–Yvon (BBGKY) equation chain. It is derived mainly from the Hamilton ordinary differential equation (ODE) system for the particle states in the position-momentum phase space. Many problems beyond physics or chemistry, for instance, in the living-matter sciences (biology, medicine, ecology, and sociology) make it necessary to extend the notion of a particle to an individual, or active particle. This challenge is met by the generalized kinetic theory. The corresponding dynamics of the state vector can also be regarded to be described by an ODE system. The latter, however, need not be the Hamilton one. The question is how one can derive the analogue of the BBGKY paradigm for the new settings. The present work proposes an answer to this question. It applies a very limited number of carefully selected tools of probability theory and common statistical mechanics. It also uses the well-known feature that the maximum number of the individuals which can mutually interact directly is bounded by a fixed value of a few units. The proposed approach results in the finite system of equations for the reduced many-individual distribution functions thereby eliminating the so-called closure problem inevitable in the BBGKY theory. The thermodynamic-limit assumption is not needed either. The system includes consistently derived terms of all of the basic types known in kinetic theory, in particular, both the “mean-field” and scattering-integral terms, and admits the kinetic equation of the form allowing a direct chemical-reaction reading. The approach can deal with Hamilton’s model which is nonmonogenic. The results may serve as the basis of the generalized kinetic theory and contribute to stochastic mechanics of populations of individuals. 相似文献
13.
14.
重建极性连续统理论的基本定律和原理(Ⅱ)——微态连续统理论和偶应力理论 总被引:9,自引:9,他引:0
重建微态连续统理论和偶应力理论的动量和动量矩均衡定律以及能量守恒定律,并由这些定律自然地推导出相应的局部和非局部均衡方程。这些结果可由耦合型微极连续统理论过渡和归结而得到。把推导出的结果和传统的质量和微惯性守恒定律以及熵不等式结合在一起就构成微态连续统理论和偶应力理论的基本均衡定律和方程体系。还弄清了以前的各种连续统理论的不完整性层次。最后,给出了几种特殊情形。 相似文献
15.
16.
预测分析再生混凝土各组分对再生混凝土宏观力学参数的影响是开展再生混凝土基本力学性能的一种方式.为了分析再生混凝土各组分对再生混凝土宏观力学参数的影响,根据再生混凝土的细观结构组成,建立了细观等效模型,利用扭转变形、细观夹杂理论、弹性等效思想和M-T模型方法,推导了由原生骨料、老界面层、老水泥砂浆、新界面层和新水泥砂浆等组成的再生混凝土的宏观力学参数预测模型.预测结果表明,随着再生骨料的取代率增加,水泥砂浆的含量不断增加,再生混凝土孔隙率也随之增大,导致再生混凝土的Poisson比随之增大,弹性模量、剪切模量和体积模量不断降低.模型的预测结果较好地反映了再生混凝土宏观力学参数随再生骨料取代率的增加不断变化的这一趋势,也为再生混凝土宏观力学参数的预测提供了一条简单实用的新方法,有利于再生混凝土基本力学性能的研究分析. 相似文献
17.
We consider quantum mechanics for which the system time is one of generalized coordinates. The generalized Hamiltonian has an unbounded spectrum, which allows us to introduce a Hermitian time operator. In the proposed formulation of quantum mechanics, a system time and observer’s time are introduced. The Schrödinger equation in the system time either does not hold or holds only approximately. The wave function is assumed to be square integrable with respect to all coordinates, including the system time. In some limit, this formalism reproduces standard quantum mechanics and the corresponding measurement theory. 相似文献
18.
19.
Non-linear singular integral equations are investigated in connection with some basic applications in two-dimensional fluid mechanics. A general existence and uniqueness analysis is proposed for non-linear singular integral equations defined on a Banach space. Therefore, the non-linear equations are defined over a finite set of contours and the existence of solutions is investigated for two different kinds of equations, the first and the second kind. Moreover, the existence of solutions is further studied for non-linear singular integral equations over a finite number of arbitrarily ordered arcs. An application to fluid mechanics theory is finally given for the determination of the form of the profiles of a turbomachine in two-dimensional flow of an incompressible fluid. 相似文献