脑外科机器人控制系统的设计和实现

从无框架立体定向脑外科手术的临床需求出发,设计了微创神经外科机器人黎元BH 600的控制系统．分析确定了系统的控制结构及实施方案,对脑外科机器人的硬件和软件进行了设计,建立了脑外科机器人手术规划和控制平台．通过实验和临床应用结果,验证了该手术控制系统的高精度和稳定可靠性．     

档案管理信息化环境下移动存储介质的安全使用对策

在档案管理信息化环境下,信息在存储、处理和传输方式上发生了根本变化,移动存储介质得以广泛应用,监管难度增大,泄密渠道明显增多,移动存储载体造成的泄密事件不断发生。从信息安全管理入手,详细分析了当前移动存储介质管理存在的问题和隐患,提出使用了移动存储介质的安全对策,确保移动存储介质的使用安全。     

Aiming point guidance law for air-to-air missiles

A new aiming point guidance (APG) law is presented which generates a missile turn rate command proportional to the heading error, that is defined as the angle between the current missile heading and predicted aiming point. The target under consideration is assumed to be manoeuvring with constant longitudinal and/or lateral accelerations, and the missile dynamics are modelled as an acceleration-limited first-order lag point mass. The aiming point is calculated based on current intercept geometry and target velocity and position. Time-to-go, a key factor for successful interception, is estimated by a time-to-go predictor. With the heading error defined as stated above, the guidance law can guide the missile into the collision course in the early stage of the engagement. As a consequence, the later part of the missile trajectory tends to be a straight line, provided that the target maintains its current status. The performance of the proposed APG is evaluated by simulation and is compared with the proportional navigation guidance (PNG) and Kim's prediction guidance (PRG) law (Kim 1985). Numerical simulations show that APG is superior to PNG and PRG in both intercept time and miss distance     

Minimum energy control of time delay systems via piecewise linear polynomial functions

The piecewise linear polynomial function approach to the minimum energy control of linear systems with time delay, is presented in this paper. The concepts of a delay shift matrix and an operational matrix for integration are employed in solving the related state and costate equations containing terms with advanced and delayed arguments. An attractive feature of the present method is its ultimate simplicity and convenience. The differential equations with delay and advance terms are converted into a set of linear algebraic equations using a recurrence algorithm. An example demonstrates the accuracy of the method.     

Control and state observation of periodic linear multimodal systems

This paper investigates the control and state observation problem for periodic linear controllable and observable multimodal systems. For a controllable periodic linear multimodal system, this paper proposes an alternative minimum-norm dynamic state feedback control scheme for state transition matrix assignment. Also presented is a new design of state observers for an observable periodic linear multimodal system. Finally, an analysis of closed-loop behaviour of controlled periodic linear multimodal systems using a state-estimate is given     

信息隐藏的最优化模型及容量分析

在分析已知信息隐藏系统通信模型的基础上,提出了一种理论新模型,运用最优化理论的观点得出了隐藏系统的容量,对容量的存在性进行了证明,并对该模型进行了讨论。新模型重点考虑了信息隐藏系统实际存在的鲁棒性和透明性,全面综合了信息隐藏的嵌入、提取和攻击模型,对以往信息隐藏理论模型不能描述能够引起栽体尺寸变化的几何攻击的缺点做出了彻底改进。     

室内场所自主服务型机器人系统实现

随着社会的发展,自主移动服务机器人技术迅速成为服务机器人领域中的一个研究热点,具有广泛的应用和广阔的发展前景.针对研制开发的基于S3C2410微处理器的自主服务型机器人,讨论了系统的硬件设计,具体分析了各个模块的设计原理、驱动和应用软件的设计.针对办公室等室内场所,设计模糊控制器,并进行现场实验,实现了基于无线通讯的自主送水服务功能.     

基于.NET Framework的河源手机产业电子商务平台研究与开发

该文以河源手机产业电子商务平台设计与开发为例,介绍了项目成立的背景,对项目做了充分的需求分析,并分析了系统开发过程中遇到的动态导航栏目实现、B2B电子商务平台商家店面URL分配、删除数据库记录同时删除系统文件夹中对应的文件等技术要点和难点。解决了困绕众多技术开发人员的C#编程、B2B电子商务系统、B2C电子商务系统、数据获取等等问题。     

基于PLC的直线加速器联锁保护系统

介绍-个在EPICS软件环境下实现的用于加速器的联锁保护系统.系统选取以PLC为核心基于硬件的技术路线,联锁信号以硬件方式在各系统间直接连接,联锁逻辑由PLC处理完成.联锁事件的上报、存档、分析则通过EPICS控制软件系统实现,联锁事件由联锁系统PLC上报到中控系统,PLC通过以太网与EPICS通信.     

水玻璃常压制备多孔材料

以水玻璃为硅源,在酸性条件下,通过溶胶凝胶的方法,经去离子水洗去钠离子,然后溶剂交换,用三甲基氯硅烷进行表面修饰,在常压下干燥,制备成20～50nm孔径的介孔材料。