查询词典 simulation

The whole thesis can be divided into two parts.The first part is the literature review, serving as the theoretical basts for the second part, introducing the concepts such as simulation.virtual reality and their mutual relationship and also the advantages when VR and Simulation technique is applied in experiment teaching.The second part makes a detailed discussion on the overall plan, real accomplishment, key techniques and improvement envisage in virtual experiment system of computer communication.

它分为两部分，第一部分为理论概述部分，它为第二部分的介绍提供了理论支持，这一部分主要介绍了仿真，虚拟现实、仿真与虚拟现实的关系以及虚拟现实仿真技术应用于实验教学的优点等；第二部分对计算机虚拟通信实验系统的整体设计、具体实现、关键技术以及改进设想等方面作了较为详尽的阐述。

This article firstly introduced the development history of digital simulation technology and spring-back, retrospected the researches about this by scholars in-and out-country, and then related theoretical bedrocks on digital simulation.

本文首先介绍了数值模拟技术及回弹发展历史，回顾了国内外学者在这方面的研究，随后介绍一些有关数值模拟的理论基础。

In this thesis, two chemical structural models were constructed based on several structure parameters derived from FTIR and 13C NMR data, which were processed by curve-fitting and curve-resolved. Modified models were obtained by simulation oftheir molecular vibration spectra using Cerius 4.6/IR module andthe structural parameters from 13C NMR. Potential energy, bondenergy and non-bond energy of the minimum-energy conformations of coal macromolecules were calculated by molecular mechanics calculation and molecular dynamics simulation. These results demonstrate the importance of hydrogen bonding and van der Waals interactions in the formation and stabilization of coal macromolecular structure, and a strongest tendency of hydrogen bonding interactions to increase with the coal molecules but the Coulombs force.

本文运用煤结构的傅立叶红外光谱和固体核磁共振碳谱~(13C NMR测试方法所得的结果，经过谱图分峰、分析，计算出若干表征煤大分子结构参数，并综合前人的经验和共识，利用计算机分子绘图软件系统构建了表征两种褐煤的化学结构模型，在Cerius~2 4.6／IR模块中计算了分子振动红外光谱，同时结合碳谱所计算的分子结构参数拟合、修正了该结构模型，得到了能表征这两种煤样的分子结构模型，作为用分子动力学模拟和量子化学计算的初始结构模型。

The model adopts continuity equation, diffuse wave model, and the Mannings equation for surface runoff routing, while uses the Green and Ampt infiltration theory and Darcys Law for subsurface runoff treatment. Uncertainty analysis incorporating Monte Carlo simulation and a Maximum Likelihood Estimation and Efficiency Coefficient is used to retrieve optimal parameter values and to estimate the confidence interval for the simulation results.

目前已经完成模式中各相关模组的研发，包含利用DEMs 析取坡度、流向与集流面积；利用卫星影像评估土地利用类别；结合蒙地卡罗法、最大概似法与效率系数的参数率定器；以及整合Green and Ampt 的入渗理论、Manning 地表流速公式，Darey 定律和扩散波理论的水文演算模组。

The results achieved by the unsteady simulation on the basis of Reynolds averaged Navier-Stokes are fitted to the experiential wind profile well. The results indicate that the numerical simulation based on CFD provides a new solution to study the downburst wind characteristics under the current conditions without detailed full scale data.

数值结果表明，基于雷诺平均的Navier-Stokes方程进行的非定常数值模拟结果同根据实测数据提出的三种经验风剖面吻合良好，在目前实测资料稀少的情况下，有助于更好地研究下击暴流风的基本特征。

The purpose of this paper is to realize the downhole operation simulation system with the technology of Scene Simulation.

本文旨在建立一套利用视景仿真技术开发的油田井下作业视景仿真系统。

Finally,there will be a example demonstration of cooperation and simulation course,which can be demonstrated by some 3D geometry models of primary vehicle and components in railway industry,exampled by finity membersanalyse and supported by the cooperation and simulation platform.

最后，本文将以铁路车辆行业中主要车型、主要部件的3D几何模型处理、有限元分析为例，以协同仿真平台为依托，实例演示协同仿真过程。

The following exciting results are revealed: 1 When considering the influence of some nonlinear elements such as hard-limit of exciters, the effects of some devices such as Power System Stabilizer and Static Var Compensator which can introduce positive damping in power system, the reasonability of system parameter values in simulation, the SNB surface and HB surface on the boundary of SSSR will turn close to each other and even coalesce together; 2 Under some conditions, coupling between slow exciters and shunt capacitors will bring negative damping in power system dynamics, which increases the possibility of oscillatory instability. So the power system with mass shunt compensators is easily subjected to the oscillatory instability. In recent years, chaotic phenomena of power system have been reported many times. Some simulation studies even found chaos existing inside the power system SSSR. In this dissertation, chaotic phenomena in power systems are thoroughly studied in order to make clear the relation of chaos and SSSR. The following results are derived: 1 Based on Li-Yorke Theorem and their definition on the chaos, the existence of chaos in power system is verified; 2 Three possible routes of causing chaos in power system are found and deeply investigated. They are route of cascading period doubling, route of directly initial energizing and route of torus bifurcation (or quasi-periodicity). The latter two routes are investigated for the first time in power system stability studies; 3 When the stability conditions of chaos are broken, it is found they can lead to voltage collapse, angle divergence, or voltage collapse with angle divergence simultaneously.

针对在电力系统小扰动稳定区域内可能存在混沌吸引域的有关报道，本文深入研究了电力系统混沌现象的出现途径和与系统失稳模式之间的关系：1利用Li-Yorke定理和Li-Yorke的混沌定义，从理论上证明了电力系统混沌现象的存在性；2发现了电力系统中导致混沌出现的三种可能途径：倍周期分岔导致混沌、初始能量直接激发混沌和经由环面分岔导致混沌，并对后两种新发现的途径进行了较为细致的研究；3发现了混沌极限环破裂导致电压崩溃、角度失稳以及电压崩溃和角度失稳同时出现的现象，其中混沌极限环破裂导致系统角度失稳和电压崩溃及角度失稳同时出现的现象均属首次报道；4证明由微分-代数方程描述的系统模型，其小扰动稳定域的边界只包含HB、SNB和SIB三种分岔界面，在SSSR的内部和边界上，均不可能存在会导致混沌的点，从而将混沌现象排除在小扰动稳定域的研究之外，简化了后者的研究工作。

Applying the theories of thermodynamics and mechanics, the working process of basicAPE--single-stage expansion, is analyzed and its related mathematicmodel is built up. The simulation methods based on this model are discussed, which is the preparation for the later research work.Chapter 3: The working characteristics of the single-stage expansion engine are researched on by the simulation.

运用热力学和力学理论对最基础的气动发动机——单级膨胀气动发动机的工作过程进行了研究分析，建立了相应的数学模型，讨论了应用该模型对气动发动机进行理论分析的仿真计算方法，浙江大学博士学位论文：气动发动机探索性研究为后续理论研究打下基础。

Using the large eddy simulation and particle direct simulation, the diffusion of particle in sudden expansion pipe is modeled.

对江水换热引起的污垢热阻，采用热力学第一、二定律和熵产分析法，分析污垢对管内对流换热过程性能的影响。

Breath, muscle contraction of the buttocks; arch body, as far as possible to hold his head, right leg straight towards the ceiling (peg-leg knee in order to avoid muscle tension).

呼气，收缩臀部肌肉；拱起身体，尽量抬起头来，右腿伸直朝向天花板（膝微屈，以避免肌肉紧张）。

The cost of moving grain food products was unchanged from May, but year over year are up 8%.

粮食产品的运输费用与5月份相比没有变化，但却比去年同期高8％。