一种基于距离和角度的无线传感器网络GPSR协议

传感器节点能量是影响无线传感器网络的生存周期的关键因素,基本的GPSR协议所使用的贪婪算法忽略了角度因素对下一跳选择的影响,在转发失败遇到空洞问题时只能进行周边边界转发算法,以损耗节点能量为代价。为了节约节点能量,延长网络生存周期,从改进GPSR协议出发,综合考虑距离和角度这两个因素解决路由过程中的空洞问题。仿真实验表明,改进后的协议是网络节点消耗大大减少,网络生存时间为300 s,长于基本GPSR协议下的200 s。该协议缩短了路径长度,节约节点能量,减少能量的消耗,延长了网络生存时间。     

Database Technology in Wireless Sensor Networks

As a result of combination of microsensor technology,low power computing and wireless networking,wireless sensor networks become an active branch in scientific territory of computer science at the moment.The recent reserch work on data management of wireless sensor networks is mainly introduced. In order to achieve high performance of the data-center network system,and supply an effective sensor database administration processing system in the interest of observing person or consumer,Separately proposed valid settlement schemes for the two key problems in database technology: data model and query processing.     

Architecture and Characteristics of Wireless Sensor Networks

Wireless sensor networks (WSN) is a novel technology about acquiring and processing information. The designer of WSN must have a thorough understand about architecture, protocol and characteristics of WSN. This paper describes communication architecture, component of node and available building scheme for WSN in detail, analyzes the characteristics of all topologies, and presents a protocol stack based on layer theory. The popular wireless communication models are discussed, characteristics and features are also analyzed, which provide a guidance for designer.     

基于无线传感器网络的精准农业研究进展

无线传感器网络是集传感器、微处理器和无线通信等技术为一体的多学科的综合性技术,是当今信息领域中的一个研究热点。通过简述无线传感器网络的国内外研究现状,概括其特点与结构体系,重点分析了其在精准农业中的应用,并展望了其发展趋势。认为以无线传感器网络技术为基础的农业物联网是精准农业的发展方向。     

Routing protocol of the wireless sensor networks for bridge health monitoring

By analyzing the reason that why the existing routing protocols cannot be applied to the wireless sensor networks for bridge health monitoring, a new routing protocol is proposed. Since the locations of the collecting modules are fixed, the proposed protocol exchanges the routing information between the neighbor nodes by adjusting the exchange cycle according to reliability of the modules. For the low routing security requirement, while to increase the routing efficient, the middle nodes replying the routing requirements with variable thresholds is introduced. In order to make full use of information in route discovering procedure, the backup routes mechanism is adopted. The proposed protocol can efficiently forward data and is suitable for the bridge health monitoring.     

基于无线传感器网络的森林火情实时监测系统

为了实现森林火情监测过程的自动化、智能化和网络化,提出基于无线传感器网络的森林火情实时监测系统。该系统由无线传感监测网络和监控中心2部分组成,可实时、在线、精确获取森林气象及火场环境信息,具有部署灵活、维护方便、成本低廉、扩展性好等优点。移动节点的引入进一步加强了消防人员的安全保障和监测系统的可靠性。将该系统应用在情况复杂多变、实时性要求很高的森林防火,能显著提高救灾效率,减少火灾所带来的人员和财产损失。     

An improved HEED clustering algorithm for Wireless Sensor Network

In wireless sensor network, routing protocols which based on clustering have the advantages of energy consumption, topology management and data fusion. The HEED protocol, which generates cluster heads based on distributed algorithm, drives up the rate of clustering and creates well distributed cluster heads. However, it does not consider the mobility of nodes in the network. When the distance between neighbor nodes has changed, the AMRP method which decides the node belongs to different cluster heads would cause problems such as high energy consumption, short lifetime of network and so on. Responding to these problems, the paper proposes the S HEED, a clustering algorithm based on stability, which chooses the stability as a parameter of nodes when choosing a cluster head. With S HEED algorithm, the high energy consumption problem among cluster nodes and cluster heads caused by the mobility is tackled. The simulation experiment demonstrates that the S HEED algorithm lower the energy consumption of cluster heads and prolongs the network lifetime.     

蔬菜温室WSN路由算法研究

以无线传感器网络在蔬菜温室环境监控中的应用为目的,研究几种常用自组网路由算法原理。通过对ABR、TORA、DSR、DSDV、AODV等不同路由算法的分类归纳和各自优缺点对比,得出AODV算法因在降低开销的同时还能减小通信延时而最适用于无线传感器网络的结论,因此以实际应用为目的对AODV算法的工作原理进行研究和梳理。使用NS2和NAM网络仿真工具对使用AODV算法的无线传感器网络进行模拟场景仿真,使用gwark和gnuplot工具对仿真数据进行分析,重点研究一定区域面积下节点数量增加时网络传输延时和丢包率的变化,得出应用场景确定时节点数量对通信质量的影响关系,为今后WSN在蔬菜温室中的实际应用提供理论依据。     

A borrowed address based on efficient distributed address assignment algorithm in ZigBee networks

The borrowed address algorithm can solve the orphan problem made by the restriction of threshold of children when DAAM(distributed address assignment mechanism) assigns the addresses for the nodes in ZigBee networks. The exited borrowed algorithms only can increase the success ratio of address assignment, but their overhead and times spend on founding net cost much. To address the problem, we propose an efficient borrowed address assignment algorithm EDAA BA (efficient distributed address assignment algorithm based on borrowed address). To control the overhead and time spend on founding net, it borrows addresses firstly from the descent nodes in same branch for the orphan router nodes, adds the mechanism of immediate reply of borrowed message, and assigns the remainder addresses unused by DAAM in the 16 bits addresses for the orphan end devices. Theoretical and simulation analyses show that our algorithm outperforms DAAM and two of its present improvement algorithms in terms of the overhead and time spent on forming network, under the premise of better success rate of address assignment.     

Fault-tolerant Wormhole Routing Algorithm for Honeycomb Networks

Honeycomb meshes are topological structures for connecting processors within parallel computers. The unicast routing strategy on honeycomb meshes are studied. It is indicated that a previous known routing algorithm may suffer from deadlock. A deadlock-free routing algorithm known as the XYZ-ROUTE algorithm is presented by employing the classical virtual channel technique. This algorithm is improved to make it work properly in the presence of convex faults.     

Lifetime of Event-driven Wireless Sensor Networks

研究了不同处理对磨盘柿贮藏过程中生理生化变化的影响.结果表明,0℃条件下真空包装冷藏能明显地延长磨盘柿保鲜期,在贮藏3个月后硬度仍能维持在1.97 kg,柿果实可溶性固形物、可溶性糖以及可溶性单宁变化与保鲜膜处理无明显差异,但类胡萝卜素含量却远远低于对照与常温条件下保鲜膜处理,此外,常温条件下縻盘柿果实贮藏不宜采用真空包装,保鲜膜包装并不能延长保鲜期,但能有效地抑制蒸腾失水,对于维持磨盘柿果实光洁、饱满的外观形态具有一定的辅助作用.     

Optimal sensor deployment scheme for heterogeneous wireless sensor networks

For the high density of distributed heterogeneity nodes in wireless sensor networks (WSNs), the optimal sensor deployment is studied. A cost optimal heterogeneous sensor deployment scheme based on genetic algorithm is proposed. The cost of sensor node deployment is used as objective function for optimization computation subjected to network coverage and fault tolerance to obtain the suitable types and positions of the sensors. The algorithm can be used for boolean sensing model as well as probabilistic sensing model. The simulation results demonstrate that the proposed algorithm converges fast toward the optimal solutions and reduces the cost of sensor deployment, which is feasible for heterogenous nodes deployment in WSNs.     

Building Wireless Sensor Networks(WSNs) by Zigbee Technology

ZigBee technology is a new and exoteric wireless interconnection technology . Sensor Networks is combined by senor technology , ZigBee, IEEE 1451.2 and route protocol. This paper puts forward the implementation of each module on the wireless gas meter data -transmitting system.     

规模化养鸡场环境温湿度无线监测仪的设计研究

为实现鸡舍内温湿度的远程监控,便于适时调整舍内的温湿度。基于无线单片机CC1110、数字温度传感器DS18B20、湿敏电容湿度传感器KSC-6V和微型液晶显示器1602LCD,设计了鸡舍环境温湿度微型无线监测仪的硬件电路及其C语言驱动程序。该监测仪精度高、成本低廉、结构简单、安装操作方便,且信号传输距离远,能够满足鸡生长过程中对温湿度监测的要求,具有很好的应用价值。     

基于无线传感器网络和WebGIS的墒情监测系统

为了解决墒情监测中便携式监测仪数据存储、发送困难及墒情实时监测和分析等问题,建立了基于无线传感器网络和WebGIS的墒情监测系统。系统以STC单片机为核心芯片,结合GPRS模块、GPS模块,通过无线传感器网络技术,实现土壤水分数据的实时监测及无线传送。建立了数据库,接收监测点数据。并以SuperMap IS.NET和SQL Server 2005为开发平台进行二次开发,将GIS技术与墒情监测结合起来,根据作物耕作深度、作物生长期对土壤含水量进行判断,得出墒情结果。实现墒情监测点信息、土壤含水量曲线图、等值线分布图在Web服务器上的显示。墒情监测系统的建立和使用,对农业生产有深远的意义。     

基于无线传感器网络的智能粮仓监控系统

分析了目前粮仓监控的现状,设计了一个基于无线传感器网络监控系统体系结构.设计了系统的GSM通信模块,给出了系统数据传输数据的设计,及系统端口初始化的核心代码,设计了系统智能监控流程,从而解决了系统开发运行的难题.最后通过系统的试运行,验证了系统的设计与开发思路的正确性.     

无线传感器网络中一种改进的DV-Hop定位算法

针对DV-Hop算法在无线传感器网络节点分布不均匀时定位误差比较大的问题,提出了一种针对DV-Hop的改进定位算法。该改进算法主要是利用RSSI测量技术增加锚节点;在给定约束下引入“可能存在区域”这一概念,并以该可能存在区域的面积作为目标函数,对未知节点的位置利用非线性共轭梯度法进行逼近,从而使节点定位误差达到最小。通过仿真验证了节点通信半径和锚节点比例对定位误差的影响,结果表明,该改进算法将节点定位精度提高了5%~10%。     

The optimal energy efficiency of wireless networks nodes based on solar cells

To improve the energy efficiency of solar cells in wireless sensor networks nodes, the energy relationship between solar cells and the wireless sensor networks nodes is studied. An adaptive algorithm is adopted to ensure the wireless sensor networks work normally at different sunlight intensities. An energy model is designed that reveals the energy relationship between the output power of the solar cells and the power of nodes working normally at a standard sunlight intensity. The experimental results show that the model represents the adaptive energy relationship between the solar cells and the nodes, ensures that the nodes work stably in a long term, and extends the life cycle of the sensor networks as long as possible. The model has important guiding significance for wireless sensor networks designation.     

A cooperative localization algorithm for wireless sensor networks

Aiming at the shortcomings of the existing RSS(received signal strength) based localization algorithm for wireless sensor networks (WSN), a cooperative localization algorithm (CLA) is proposed. A reference anchor node is introduced to tolerant some minor error including the node position error. Dixon detection method is applied to remove abnormal RSS values, while the standard deviation threshold of RSS and learning model are introduced to reduce the RSS ranging error and effectively improve the precision. Simulation experiments are performed to evaluate the performance of the proposed algorithm. The results demonstrate that the localization accuracy is improved effectively, while the stability and robustness are better.