Coverability of Wireless Sensor Networks

The coverability of Wireless Sensor Networks (WSNs) is essentially a Quality of Service (QoS) problem that measures how well the monitored area is covered by one or more sensor nodes.The coverability of WSNs was examined by combining existing computational geometry techniques such as the Voronoi diagram and Delaunay triangulation with graph theoretical algorithmic techniques.Three new evaluation algorithms,known as CRM (Comprehensive Risk Minimization),TWS (Threshold Weight Shortest path),and CSM (Comprehen...     

Distributed Dynamic Navigation for Sensor Networks

Navigation with sensor networks has shown many advantages and great potential in many scenarios.Previous works have mainly focused on selecting the shortest path to navigate an internal user out of an emergency field.However,they did not consider variations of the dangerous areas which usually occur in practical applications.This paper presents an efficient dynamic routing algorithm to successfully guide users to the destination exit.The navigation goal is looking for a safe and short path to enable the user to escape from a dangerous area as fast as possible.Without knowing the locations of the nodes,the user is guided by a sequence of sensor nodes to pass through the dangerous areas.The algorithm ensures the navigation path security by predicting the dynamic changes affecting the navigation path.The performance of this approach is evaluated using extensive simulations to validate its effectiveness.Simulations show that the approach is scalable and performs well in various settings.     

Graft Modification of N,N''''-methylene- bisacrylamide onto Silk in the Presence of Air

The graft modification of N, N'-methylene-bisacrylamide (NNMBAA) onto silk using eerie ammonium sulfate, potassium persulfate, ammonium persulfate and 2, 2-azobis (isobutyronitrile) as the initiators has been studied in the presence of air. To establish reaction conditions for the graft modification of NNMBAA onto silk, the effect of different variables such as the initiator concentration, monomer concentration, acetic acid concentration, time of polymerization, reaction temperature and liquor ratio (fabric: liq.) have been studied. The optimum grafting conditions were found. As evidence of grafting, analyses of amino acid composition and alkali solubility have been carried out. Grafting caused changes in amino acid composition and alkali solubility of silk. The observation has been explained in relation to structural changes in the grafted silk.     

Effects of the Water in Mixed Solvent on the Epoxidation Reaction of Propylene with TS-1 Catalyst

The epoxidation reaction of propylene and hydrogen peroxide with zeolite catalyst containing titanium-silicalite (TS-1)has been studied, and the reaction in the mixed solvent of water/methanol has been discussed. It is shown that the selective of epoxidation propylene decreases while the selective of propylene glycol increases, when the water content increases in the mixed solvent of me thanol/water.     

移动通信信号到达时间差定位的估计

到达时间差(TimeDifferenceofArrival,TDOA)位置估计是无线定位的一项关键技术.首先介绍了TDOA定位估计原理,阐述了基站任意分布时(以三基站为例)的二维定位估计,以及在特殊情况下,即基站线性分布时的定位估计.最后,对三基站TDOA定位估计及其定位精度进行了仿真,为第三代移动通信无线定位系统的研究和开发提供了理论基础.     

微机数据库在高校仪器设备计算机管理系统中的应用

高等院校仪器设备数量多,规格品种多,精贵设备多。为了对设备进行有效地管理,尽可能提高设备利用率,作者在IBM—PC/XT机上研制了一个仪器设备管理系统(以下简称系统)。一、系统概况系统在操作系统DOS3.0(或2.0)版支持下,用C—COBOL,编译:BASIC和DBASE     

波浪计算中的一个局部变分法

本文提出了一个改进的局部变分法以计算波浪绕流问题，和已有的局部变分法相比，不增加新的未知量且易于编制计算机程序．     

论高校体育课程教学改革

要将体育课程教学模式和内容达到多样化、实用化； 充实理论教学； 开展选项教学； 注重学生的能力培养     

故障诊断专家系统学习机制

根据机器学习的特点，提出并设计了一种能在故障诊断过程中进行参数修正学习、知识扩充，并在诊断结束后能对知识进行归纳的专家系统学习机制。这一系统在可视化工程环境（ＶＥＥ）平台下实现，能有效地运行，使用方便。