基于Matlab Simulink和VR工具箱的双足行走仿真

在Matlab环境下,通过Simulink和VR工具箱完成双足仿生行走的虚拟现实仿真.利用V-Realm Builder 2.0构建出双足行走虚拟三维模型,并通过虚拟现实工具箱的Simulink接口将人体下肢行走控制系统的Simulink模型与该三维模型建立关联,从而设置相关参数,通过Simulink模块输出的相应信号...     

基于MATLAB虚拟现实工具箱的手臂康复机器人仿真

基于MATLAB虚拟现实工具箱允许MATLAB／Simulink使用虚拟现实的图形技术，使用户直接将仿真结果以虚拟现实的形式显示出来．介绍了虚拟现实的基本概念、V—realm Builder，及建立手臂康复机器人虚拟现实的VRML语言文件，并且在MATLAB和Simulink环境下，对手臂康复机器人进行虚拟现实仿真。仿真结果表明，虚拟模型可以准确地模拟真实康复机器人的特征，为实现对真实机器人的最优控制和设计提供了理论依据。     

基于神经网络的机器人无标定视觉伺服系统仿真

针对机器人三自由度平动的视觉定位问题,建立全局有效的非线性视觉映射关系模型,并设计人工神经网络（ANN）Xff其拟合,从而实现无标定视觉伺服．伺服系统的物理结构采用单目视觉和眼在手上（eye。in。hand）构型．机器人系统采用典型工业机器人puma560,并限定末端姿态使其保持平动．基于机器人工具箱（roboticstoolboxforMatlab）和神经网络工具箱,在Matlab／Simulink环境下建立仿真模型,对系统的开发具有重要的参考意义．仿真结果表明,该系统对静态物体的定位能够达到较快的响应和较高的精度．     

具有随机丢包的无线网络控制系统仿真研究

本文介绍了一种基于Matlab/Simulink的联合仿真工具——TrueTime工具箱,利用该工具箱并以直流伺服电机为受控对象,建立起一个单包传输有随机数据包丢失的无线网络控制系统的仿真模型.通过仿真实验研究数据丢包对于系统控制性能的影响,对比当出现数据丢包时,控制器采用上一时刻的控制律与不采用任何控制律的控制效果,两者并没有明显差别.     

基于Matlab/Simulink表面式永磁同步电机控制系统仿真研究

基于表面式永磁同步电机数学模型和磁场定向控制,利用Simulink工具箱搭建了表面式永磁同步电机控制系统的速度和电流双闭环仿真模型,验证了id=0控制算法,以及该模型的有效性。     

KNT-ESR3机器人运动学建模与仿真研究

以KNT-ESR3机器人为研究对象,采用D-H参数法,利用Matlab机器人工具箱Robotics Toolbox建立机器人运动学模型,进行运动学分析与逆运动学求解,实现了机器人空间轨迹规划及其仿真.结果表明,计算与仿真验证了机器人运动学模型建立的正确性,依据该模型能够有效地生成运动轨迹并分析机器人各关节的运动参数,为开展该机器人的研发工作做了理论铺垫.     

后轮毂电机独立驱动电动车的驱动控制研究

针对后轮毂电机独立驱动的电动车,研究其驱动控制系统.分别分析了直线行驶和转向行驶时的运动状态,根据经典Ackermann-Jeantand转向模型建立转向运动学方程并构建驱动控制系统,遵循转向降速的原则,以两前轮转速差为参考控制两后轮转速差,快速并准确判断汽车的行驶状况,采用PID算法,输出PWM调节后驱动轮转速.Matlab/Simulink仿真表明,该驱动控制系统能保证电动车直线行驶平稳和转向差速可靠.     

基于TrueTime的网络控制系统仿真平台的构建及其仿真分析

TrueTime是基于MATLAB/Simulink的网络控制系统仿真工具箱,是目前使用较为广泛的网络控制系统虚拟仿真工具。介绍了一种基于TrueTime的网络控制系统仿真平台,并用基于TrueTime的弹簧-阻尼系统仿真模型为实例,说明该仿真平台的构建方法,同时通过与MATLAB的阶跃响应曲线对比,证明该仿真模型可以很好地模拟网络环境。针对网络控制系统中网络时延和数据包的丢失这两个主要问题,通过对仿真结果的分析,验证网络时延、数据丢包等因素对网络控制系统控制性能的影响。     

应用Matlab设计人工神经元网络控制系统

在简要介绍Matlab5.3软件的基础上，结合它的神经网络工具箱，阐述了在Matlab软件中利用神经元网络工具箱（Neural Network Toolbox)和Simulink平台建立人工神经元网络模型以及实现人工神经元网络控制系统的设计、仿真和动态性能分析的方法，并以倒立摆控制系统为例进行了仿真研究。文中的具体实例表明，在人工神经元网络及其应用研究中使用Matlab可以提高研究效率，快速实现研究构想，有助于科学研究工作的开展。     

基于组态王与Matlab的三容水箱多变量虚拟控制系统

基于组态王和Matlab构建了一个三容水箱液位控制的虚拟仿真系统.首先利用组态王搭建了液位控制系统监控画面,其次依据现代控制理论建立其数学模型,并使用Simulink工具箱构建多变量控制系统,然后通过OPC数据通信技术建立了组态王界面和Simulink的连接,最终实现了多变量控制系统的动态监控、实时曲线查询、历史数据查询和报警等功能.实验结果表明,该虚拟仿真系统简单易操作,动态画面效果逼真,可以用于多变量控制系统的学习与培训.     

Markedness and its Interpretation in Language Use

Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.     

Features of Women's language

Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women＇s language from these perspectives： pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women＇s language, more attention should be paid to language use in social context. What＇s more, the linguistic phenomena in a speaking community can be understood more thoroughly.     

An Analysis of Catherine＇s Character——Wuthering Heights

Wuthering Heights, Emily Bronte＇s only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.     

Lower Paleozoic oil relationships within Williston Basin, Canada

The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.     

低渗透非均质砂岩油藏启动压力梯度研究

理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。     

On Tragic Consciousness In The Works By Ernest Hemingway

As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.     

Achieving Unusual States of Matter Under High Pressure

正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-     

Exchange-Correlation and Electronic Excitation Energies from Pairing Matrix Fluctuations

We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-     

Density Functional Theory for the Response of Periodic Systems to Electric Fields Based on the Vector Potential Approach

正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that     

On the Thermodynamic Limit for Responses to Static Electromagnetic Fields

For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the