基于门限密钥机制的MANET组播通信系统

把门限秘密共享技术应用到移动自组网中,可以构建一个能提供高效可靠安全保证的通信系统。本文详细描述了该系统的结构和网络层的设计以及相关的安全问题,最后对一典型应用场景进行了实验。实验表明该设计方案可行,使得系统安全性更高,更加高效、可靠。     

基于Web Service的Web-OA认证系统及实现

随着信息技术、网络技术的飞速发展，网络的应用越来越广，为了能够提高企业网的安全性和加强对企业网的管理，迫切需要一个安全、可靠、高效的认证系统。本文通过对目前网络办公环境中认证系统发展状况的分析，阐述了建立统一认证系统的重要性，并以测绘院用户认证系统为例提出了一套安全、可靠、高效的统一认证解决方案。     

COTN:基于契约的信任协商系统

基于改进的信任管理和协商技术，通过属性信任证实现多种类型的权限委托，设计并实现了一个基于契约的信任协商（COntract-based Trust Negotiation，COTN）系统．在该系统中，引入了基于契约的信任协商方法，既在契约确立过程中预先终止无法进行的协商请求，又在契约约定下的协商过程中研究了对信任证和访问控制策略中隐私信息的保护，以高效、可靠地自动建立信任关系．目前，COTN系统已在网格中间件平台CROWN中得以应用，并采用信任票据和策略缓冲机制提高系统运行性能．通过相关实验表明该系统具有较好的稳定性和可用性．     

基于B／S模式的信息查询在电能量采集与分析系统中的应用

针对电能量远程数据采集与分析系统信息量大．数据类型多．需面向不同用户的特点，设计了一种基于浏览器／服务器模式(B/S)的“综合开放“的信息查询系统。该系统可以实现对不同的用户提供不同的信息查询功能，对各类数据的分析比较具有灵活性，结果显示具有多样性。采用的是web开发工具—ASP技术。实际的应用表明该系统可靠．高效且易于使用．扩展和维护。     

交流变频调速系统的一种复合制动方案

本文提出了一种回馈制动和能耗制动相结合的变频调速系统的复合制动方案，并给出了实验结果。该方案兼具能耗制动和回馈制动两种方案的优点．而且实现容易，具有安全、高效、快速和低成本的特点．它在中小型变频调速系统中具有较大的实用价值。     

远方安全监视和图象传输系统

本文叙述了一个用于无人值守变电站的安全监视与图象传输系统。该系统利用计算机多媒体技术安全、可靠、高效地完成图象、语音、文本等信息的实时处理，存储管理与站间通讯与控制等功能     

基于Granite Data Services的Web监控系统

基于Flex、GDS、Spring和Hibernate框架，设计了全新的Web监控系统并应用于供热监控系统，简化了监控系统的开发．提高了项目开发进度克服了传统Web监控系统的页面刷新难题以及基于AJAX技术的安全难题和浏览器不兼容问题系统应用表明，该系统运行稳定可靠，实时性好，具有一定的实用性和推广价值．     

光电转速传感器分布式监控系统的设计

针对光电转速传感器性能指标测试必要性和传统测试仪的局限性，引入实用而高效分布式监控系统，发挥集中管理、分散控制优势。AT89C52应用系统作为下位机，完成具体测控任务；工控机作为管理级，对系统作全面监控和管理。实践证明：该系统具有技术先进、功能可靠、实用、安全等特点、从而进一步提高了工作效率。     

电路板自动测试系统的设计和实现

介绍一种印制电路板自动测试系统的设计和实现，给出了该自动测试系统的整体结构，同时对该系统的硬件组成和软件实现作了详细说明．实际应用表明，该系统结构简单可靠．应用灵活，易扩展，在很大程度上提高了工作效率，     

基于LabVIEW的偏心桶口自动灌装系统开发

开发了基于LabVIEW及机器视觉技术的三坐标工作台灌装系统。系统使用CCD摄像机和图像采集卡采集图像。经图像标定、中值滤波、快速图像匹配等处理算法，获得偏心加注口的圆心坐标位置信息。以此控制三坐标工作台步进电机的运动。步进电机带动加注枪．实现偏心桶口的自动定位。实验证明，该系统运行可靠，算法高效、稳定，有较高的实用价值。     

基于GPS和GPRS的嵌入式车载防盗系统

针对目前车辆防盗设备存在的问题及市场应用前景,提出了一种新型嵌入式车载防盗系统的设计方案.首先以S3C2410X为核心处理器、GPRS模块和GPRS模块搭建硬件平台,然后详细介绍了车载系统以及GPS和GPRS的软件设计.实验证明,本系统稳定可靠,通信效率高.对车载防盗系统的进一步实现具有参考价值.     

Numerical approach for solving linear Fredholm integro-differential equation with piecewise intervals by Bernoulli polynomials

In this paper a numerical method is given for the solution of linear Fredholm integro-differential equation (FIDE) with piecewise intervals under the mixed conditions using the Bernoulli polynomials. The aim of this article is to present an efficient numerical procedure for solving linear FIDE with piecewise intervals. This method transforms linear FIDE with piecewise intervals and the given conditions into matrix equation which corresponds to a system of linear algebraic equation. Finally, some experiments and their numerical solutions are given. The results reveal that this method is reliable and efficient.     

基于IEEE802.1x的网络准入控制系统设计与实现

为确保本地网络资源的安全,可在网络边界处部署防火墙、安全认证网关等设备,但局域网内用户可未经授权访问关键的IT资源,占用宝贵的网络资源甚至发起攻击。为解决这个问题,本文设计了一种基于IEEE802.1x的网络准入控制系统,深入分析了802.1x协议及网络准入控制系统体系结构,通过将802.1x与RADIUS认证服务器结合构建了一个高效、可靠的内部网络802.1x/EAP接入方案,并在网络环境下进行了实验。     

An enhanced topological map for efficient and reliable mobile robot navigation with imprecise sensors

An enhanced topological mapping system for efficient and reliable navigation is presented. The map has a topological framework and some additional features. Firstly, it utilizes such rough metrical information as the length and orientation of the links. Secondly, it provides a reliable localization algorithm with which the robot first finds the interval describing the robot’s probable location by estimating the projected traveled distance using dead reckoning and then fine-tunes the estimation using landmark detection modules. Finally, it provides a planning algorithm with which the robot’s path is chosen so that the robot reaches the goal location as fast as possible without losing its way despite using such imprecise sensors as ultrasonic range finders.We have implemented and tested the proposed mapping system both on a simulator and a real mobile robot, the CAIR-2. This paper also describes landmark detection modules that utilize ultrasonic range finders. Although landmark detection modules are too simple and imprecise to estimate position by themselves, these experiments show that the proposed mapping system can reliably guide robots.     

Computationally efficient solutions for tracking people with a mobile robot: an experimental evaluation of Bayesian filters

Modern service robots will soon become an essential part of modern society. As they have to move and act in human environments, it is essential for them to be provided with a fast and reliable tracking system that localizes people in the neighborhood. It is therefore important to select the most appropriate filter to estimate the position of these persons. This paper presents three efficient implementations of multisensor-human tracking based on different Bayesian estimators: Extended Kalman Filter (EKF), Unscented Kalman Filter (UKF) and Sampling Importance Resampling (SIR) particle filter. The system implemented on a mobile robot is explained, introducing the methods used to detect and estimate the position of multiple people. Then, the solutions based on the three filters are discussed in detail. Several real experiments are conducted to evaluate their performance, which is compared in terms of accuracy, robustness and execution time of the estimation. The results show that a solution based on the UKF can perform as good as particle filters and can be often a better choice when computational efficiency is a key issue.     

基于传感器网络和有源RFID的集装箱管理系统

针对堆场集装箱管理调度问题,结合传感器网络和有源RFID技术设计一个管理系统。提出4层架构解决方案,设计高效的传输协议和结合堆场实际情况的集装箱定位算法。实验结果表明,该系统有助于解决集装箱管理中较易出现的并会带来较大损失的“丢箱”问题,具有一定应用价值。     

An efficient and robust content delivery solution for IEEE 802.11p vehicular environments

Vehicular networking is a new field that is expected to be widely adopted in the near future. One of the key applications inherent to this novel communications paradigm is content delivery to on-board users. In this paper we focus specifically on the design of a robust and efficient broadcast-based content delivery system. In order to reduce the content delivery time to a minimum, we first optimize performance by seeking the optimal packet size for content delivery. This goal is achieved by combining analytical and simulation results, and considering both static and mobile receivers at different distances from the transmitter. Moreover, we develop a full architecture that integrates the FLUTE protocol with different Forward Error Correction (FEC) schemes to achieve efficient content distribution. Through real experiments in a vehicular testbed we demonstrate that Raptor codes are the best option among the different FEC schemes available. In addition, as vehicle speed and/or distance from the broadcasting antenna increases, performance results highlight that adopting efficient FEC schemes becomes mandatory to achieve efficient and reliable data content delivery.     

An efficient split-step compact finite difference method for the coupled Gross–Pitaevskii equations

ABSTRACT

In this study, we propose an efficient split-step compact finite difference (SSCFD) method for computing the coupled Gross–Pitaevskii (CGP) equations. The coupled equations are divided into two parts, nonlinear subproblems and linear ones. Commonly, the nonlinear subproblems could be integrated directly and accurately, but it fails when the time-dependent potential cannot be integrated exactly. In this case, the midpoint and trapezoidal rules are applied approximately. At the same time, the split order is not reduced. For the linear ones, compact finite difference cannot be designed directly. To circumvent this problem, a linear transformation is introduced to decouple the system, which can make the split-step method be used again. Additionally, the proposed SSCFD method also holds for the coupled nonlinear Schrödinger (CNLS) system with time-dependent potential. Finally, numerical experiments for CGP equations and CNLS equations are well simulated, conservative properties and convergence rates are demonstrated as well. It is shown from the numerical tests that the present method is efficient and reliable.