Theory of Numerical Modeling of Constitutive Relation for Geotechnical Materials

Under the direction of the principle of interaction between plastic volumetric and shear strains, the general expression of constitutive relation for geotechnical materials has been derived within the framework of irreversible thermo- dynamics. The constitutive modeling, in fact, is an inverse problem that belongs to the medium inverse problems of model identification, which is expressed as a reversion of coefficient of differential equation. Thus the constitutive modeling of geotechnical materials will become the reversion of coefficient functions of the general expression of constitutive relation, which is carried out in the stress field （p,q） by means Of numerical techniques, so that is called numerical modeling. Applying the numerical modeling, a number of plasticity-based models for clay and sand have been obtained, which are able to characterize the fundamental features of deformation for geotechnieal materials. In addition, the approach of numerical modeling also can be applied to the situation of unsaturated soils by means of the Bishop＇s effective stress formula and Khalili＇s expression of effective stress parameter.     

The Elite Strategies in the CIMS Subject of China 863 Program（1986—2000）

Manpower is the key factor to the success of the CIMS Subject of China 863 Program.Many manpower strategies have been used in the CIMS Subject,which include elite strategies,training and practicing strategies,and culture strategies.This paper is mainly about the elite strategies such as to discover the talents,to cultivate the elites and to establish the mechanism for the expert groups to work in team,echelon and vigor.     

Two-Phase Flow Modeling in a Single Closed Loop Pulsating Heat Pipes

Mathematical modeling of pulsating heat pipes through 'first’ principles is a contemporary problem which remains quite elusive. Simplifications and assumptions made in all the modeling approaches developed so far render them unsuitable for engineering design. In this paper, a more realistic modeling scheme is presented which provides considerable try for thought toward the next progressive step. At high enough heat flux level, closed loop pulsating heat pipes experience a bulk internal unidirectional fluid circulation. Under such a condition, conventional two-phaseflow modeling in capillary tubes may be applied. This has been attempted for single-loop PHPs. A homogeneous model and a separated two-fluid flow model based on simultaneous conservation of mass, momentum and energy, have been developed for an equivalent 'open flow' system. The model allows prediction of two-phase flow parameters in each subsection of the device thereby providing important insights into its operation. The concept of 'void fraction constraint'in pulsating heat pipe operation is introduced and its relevance to future modeling attempts is outlined.     

Air Filter Simulation by Geodict

IntroductionThe previous approach for modeling the particlefiltration process has been to represent the complicatedfilter structure by a single element and then compute thefluid flow and particle transport around the one element[1,2]. The particletransport was computed byseparately addingthe contributions due to diffusion and inertia to the integratedtrajectory. The problem withthese previous approaches is thatonly general trends can be obtained from the computations ,and considerable amount o…     

The Training and Culture Strategies in the CIMS Subject of China 863 Program（1986—2000）

Manpower is a key factor for the success of the CIMS Subject of China 863 Program. Many manpower strategies have been used in the CIMS Subject, which include elite strategies, training and practicing strategies, and culture strategies. This paper is mainly about the training and cul-ture strategies such as to pay attention to the training and the practice of the technical team, and to form a fine CIMS culture.     

On-line Weighted Least Squares Kernel Method for Nonlinear Dynamic Modeling

Support vector machines （SVM） have been widely used in pattern recognition and have also drawn considerable interest in control areas. Based on rolling optimization method and on-line learning strategies, a novel approach based on weighted least squares support vector machines （WLS-SVM） is proposed for nonlinear dynamic modeling. The good robust property of the novel approach enhances the generalization ability of kernel method-based modeling and some experimental results are presented to illustrate the feasibility of the proposed method.     

Large Scale Finite Element Modeling,Simulation and Visualization for Wind Flows in Urban Area Using Virtual Reality

A large-scale finite element modeling, simulation and visualization for wind flows are presented. The modeling method using GIS/CAD data is employed. The stabilized parallel finite element method based on SUPG/PSPG method is employed for the analysis of wind flows. The present method is applied to the simulation of wind flow and contaminant spread in urban area. The visualization based on virtual reality is employed to evaluate the mesh quality and computational results. The computed results are qualitatively in agreement with the experimental results and actual phenomena. The present method is shown to be a useful tool to simulate the wind flows in urban area.     

Factors Affecting the Choice of Learning Strategies

Learners have been found to vary considerably in both the overall frequency with which they employ strategies and the particular types of strategies they use. Factors which affect the choice of the strategies are many: degree of awareness, stage of learning, task requirements, teacher expectations, age, general learning style, personality traits, motivation level, and purpose for learning the language. For example, highly motivated learners may use a greater range of appropriate strategies than less motivated ones do. Older learners may use different strategies than the younger ones in performing the same learning task. Therefore, an awareness of these factors is the key step to help learners to choose the strategies properly.     

Effects of reconfiguration on the performance of mobile navigation robot

An irmovative mobile robot that has reconfigurable loeomotion chassis and reconfigurable bionic wheels has been developed to meet the needs of different payload and different terrain. Several prototypes have been achieved by the recortfiguration. By modeling relative comparison coefficients, these prototypes are analyzed in terms of geometrical parameter of trafficability, static stability and maneuverability. The effects of reconfiguration on these indices of robot performance can be compared, i.e. the variable height of chassis h has the biggest effect, the variable length of chassis 1 is the second, then is the camber angle β and the caster angle α. Some principles for reconfiguration are proposed.     

User Driven Innovation in the Building Process

During the late years there has been an ever-increasing focus on the possibilities to change the building process to raise quality on the final building products as well as the activities of actors involved in the building process. One reason for this interest is the new opportunities evolving due to introduction of advanced information and communication technology (ICT). The paper focuses on creative changes of the building process powered by user driven innovation activities. An overview of existing user driven innovation methodologies is given as well experiences from the ongoing Virtual Innovation in Construction (VIC) project. One important driving force for change is the opportunity for users to develop and articulate real needs concerning for example different functionalities of a building and its parts, but also on artifacts supporting the actual needs capture and requirements formulation during building design. A general methodological framework and meta ontology for Virtual Innovation in Construction is presented as well as findings from implementation of the method.     

基于面向对象技术和Petri网的FMS系统建模

简述了面向对象技术及Petri网的优缺点,分析了利用Petri网进行传统FMS建模的缺陷,将面向对象技术与Petri网理论结合起来,并对实际的FMS建立了一个通用模型。     

法约尔的管理原则及其在实践中的应用

法约尔作为管理过程学派的奠基人，其针对一般管理而提出的管理职能及管理原则对当今的管理仍有重要的借鉴意义，在实践中灵活运用这些基本原则，对做好一个企业、一个学校或一个单位将具有事半功倍的效果。     

数学建模素质评估的定量分析

针对海南大学学生参加数学建模竞赛的实际情况,应用层次分析法和动态规划的理论方法对数学建模队员的选拔问题进行了建模和分析.在兼顾公平选拔原则的基础上,对学生素质进行了综合评定,给出了最佳的分组原则.     

非线性电阻Pspice模型的建立

提出一种基于Ｐｓｐｉｃｅ上新颖的非线性器件的方法，并以非线性电阻为例具体加以实现，该模型是一个通用子电路模型，并且可以应用于任何电路仿真及电力半导体器件建模中，由于在该模型的建立中采取了非线性函数的曲线拟和方法，使得原先在Ｐｓｐｉｃｅ中无法实现的非线笥器件可以通过易于实现的受控源来模拟拟和多项式函数。     

工程化领域本体建模的研究

针对本体建模没有统一的标准化指导方法,在分析本体构建原则和现有构建方法的基础上,借鉴软件工程中成熟的方法。阐述了一种普遍适用的领域本体构建方法,并提出了具体实现步骤和应用前景。     

基于UML的锅炉水处理检测系统分析与设计

统一建模语言UML（Unified Modeling Language）是一种通用的、功能强大的面向对象的可视化建模语言,首先介绍UML的基础,接着以东莞市锅炉水处理检测系统的分析与设计为例,运用Visio 2003绘图,详细介绍了UML的实际建模过程.     

非线性转子系统振动的一种数学建模方法

当转子系统中的非线性较为显著时，按通常辨识建模方法获得的线性化振动微分方程模型将难以定量和定性描述转子系统的真实振动行为，从而不利于旋转机械的动力学分析、设计和故障诊断。本文提出一种转子系统非线性振动的辨识建模方法，数学处理简便规范，便于工程实施。实验结果表明．使用该方法建立的数学模型具有较高的精度．图2，表2，参12。     

电力系统网络拓扑的分析与比较

电力系统仿真是分析电网结构,潮流计算的重要手段。采用面向对象技术（OOT）进行电网建模,类型明确,方便添加新设备。通过对电力系统网络拓扑技术的较深入的研究和探讨,对比各类分析方法原理,对同样的系统进行实际分析得出,广度优先搜索法对于各种网络都可以快速进行拓扑分析。     

缺水地区水资源承载力模型研究

从水资源,环境、人口,发展之间的关系入手,分析探讨水资源承载力的内涵,研究思路、步骤,并在此基础上,初步建立了区域水资源承载力研究的模型体系,提出了提高区域水资源承载力的主要方针策略,并以关中为例,研究水资源承载力问题。     

刚柔耦合动力学的建模方法

对柔性多体系统动力学研究的若干阶段和研究现状进行回顾,对已有的刚柔耦合动力学建模方法进行总结.为了对已有的建模方法进行评价,提出了5项指标：科学性、通用性、识别性、兼容性和高效性,指出现有的建模方法尚无法满足工程实际应用的需要,应研究满足全部评价指标的刚柔耦合动力学建模方法.文中对今后柔性多体系统刚柔耦合动力学的几个研究方向进行展望,包括理论建模、计算方法和试验研究等方面.