机械臂的动态混合控制

本文研究当机械臂的终端受有约束时的控制问题,其中心内容是给出“任务规范投影算子”的概念,利用它首先将机械臂的动态方程解耦为两组方程,它们分别描述了运动与约束力,在此基础上给出了机械臂的控制律,使闭环系统跟踪期望的速度与约束力。     

Integrated Personal Mobility Architecture: A Complete Personal Mobility Solution

The high expectations and demand for users to access the Internet from anywhere at anytime has made user mobility an important part of the design and development of the next generation mobile communications and computing. Traditionally user mobility has been divided into two areas: Terminal Mobility and Personal Mobility. In recent years terminal mobility has focused on the movement of the terminal and developed extensions to IP protocols such as Mobile IP. In contrast, personal mobility has only received limited attention, and is somewhat lagging behind. This research has either focussed on personal mobility in communications or personalisation of operating environments. As a result, to date no framework for providing true personal mobility has emerged. In this paper, we introduce a new personal mobility framework called IPMoA (Integrated Personal Mobility Architecture), which integrates both aspects of personal mobility to provide a complete personal mobility solution, and illustrate the viability of this approach through a proof-of-concept implementation.     

关于移动信道分析模型的研究

移动信道特性的研究是移动通信系统研究领域中最重要的部分，也是近年来研究的热点之一。其中多径传播和阴影效应是信道的主要特点，几乎任何统计特性都建立在此基础上。主要是介绍一种移动信道的分析模型，该模型的地理环境为市区，即移动台和基站之间不存在直视波（LOS），并从多普勒功率谱的角度给出了接受信号振幅和相位的概率密度函数（PDF）盈自相关和互相关函数。     

第三代移动通信发展概况

介绍了第3代移动通信3种主流技术的市场应用、设备成熟度，以及国际和国内标准化发展状况，我国第3代移动通信技术试验的总体情况。     

中国3G运营商的目标市场与业务模式初探

中国3G业务的市场需求有两个方面：一是迅猛增长、规模庞大的用户群对移动语音业务的需求；二是较高收入用户群对移动数据业务的需求。3G运营商的目标市场包括大众用户对移动语音的需求、大众用户对移动数据业务的需求、企业用户对移动数据业务的需求以及批发型用户的需求等。本结合国内外移动运营商的数据业务开展状况，初步探讨了中国3G运营商的移动数据业务模式和3G业务的收入模式。     

Nonholonomic Mobile Manipulators: Kinematics, Velocities and Redundancies

We consider nonholonomic mobile manipulators built from an n _a joint robotic arm and a nonholonomic mobile platform with two independently driven wheels. Actually, there is no efficient kinematic formalism for these systems which are generally characterized by their high number of actuators. So, kinematic modelling is presented with particular emphasis on redundancy. Whereas kinematic redundancy is well known in the holonomic case, it is pointed out that it is necessary to define velocity redundancy in the case of nonholonomic systems. Reduced velocity kinematics based on quasi-velocities are shown to provide an efficient formalism. Two examples of mobile manipulators are presented. Finally, reduced velocity kinematics and velocity redundancy are shown to be adequate tools in order to realize operational task while optimizing criteria such as manipulability.     

Robot Pose Estimation in Unknown Environments by Matching 2D Range Scans

A mobile robot exploring an unknown environment has no absolute frame of reference for its position, other than features it detects through its sensors. Using distinguishable landmarks is one possible approach, but it requires solving the object recognition problem. In particular, when the robot uses two-dimensional laser range scans for localization, it is difficult to accurately detect and localize landmarks in the environment (such as corners and occlusions) from the range scans.In this paper, we develop two new iterative algorithms to register a range scan to a previous scan so as to compute relative robot positions in an unknown environment, that avoid the above problems. The first algorithm is based on matching data points with tangent directions in two scans and minimizing a distance function in order to solve the displacement between the scans. The second algorithm establishes correspondences between points in the two scans and then solves the point-to-point least-squares problem to compute the relative pose of the two scans. Our methods work in curved environments and can handle partial occlusions by rejecting outliers.     

IS—95CDMA系统的容量分析

容量的需求是推动ＣＤＭＡ数字蜂窝移动通信开发的主要动力。系统的容量受许多因素的影响，本文针对ＩＳ－９５ＣＤＭＡ系统在采用了功率控制、话音激活和扇区划分技术的情况下，对系统的容量进行了分析，同时也分析了功率控制精度对容量的影响。     

集群移动通信系统的组网设计

本文对集群移动通信系统在组网设计时应考虑的问题进行了分析，并提出了具体步骤和方法，可供集群系统组网设计时参考。     

用于低产和边远油井的活动采油装备

活动采油装备是利用抽汲车将抽子下入井内实施抽汲捞油作业，省去了地面及井下常规采油设备，达到了投入少，效益高，操作简便，便于管理和采油机动灵活的目的，为不能采用常规采油流程和设备的低产、低压、高含水油井和边远油井的开采提供了有效设备。采用活动采油装备在岔河集油田的25口油井内下入油管抽汲管柱、4口油井内下入套管抽汲管柱，抽油863t，获利17．67万元。这套装备仅使用半年就已收回全部投资，若推广使用，可望获得可观的经济效益。