基于PLC和无线传感器网络的光电监测系统构建

为了克服传统监测系统的不足,构建一种基于PLC和无线传感器网络的光电监测系统.在分析光电监测系统的构成及工作原理的基础上,探讨了基于遥测技术的无线光电传感器网络实现方式,研究了ABB PLC软硬件实现及FameView的开发的可行性.采用ABB公司生产的AC500 PLC作为主要控制器件,通过Modbus协议按地址依次轮询无线传感器节点来采集数据,对其进行相应处理,并将最终结果传递给上位机.上位机将获得的数据通过FameView组态软件生成监控画面,实时监测现场的运行情况.监测灵活、高效,数据采集效率较高,具备良好的扩展性.这种新型光电监测系统在企业生产、战场环境等许多军民用领域中具有重要作用.     

Single facility location on a network under mill and delivered pricing

^** E-mail: pelegrin{at}um.es Firms normally use either a mill price or a delivered pricepolicy, depending on market conditions (type of good, transportationway, customers location, costs, etc). In this paper, the problemof selecting the best location for an entering firm in competitionwith some pre-existing firms, under each price policy, is studiedon a network for the first time. With mill pricing, an equilibriumin price rarely exists and it is assumed that all competingfirms set a common mill price for all customers. With deliveredpricing, there exists a Nash equilibrium in price and it isassumed that the equilibrium price in each area is offered tothe customers in that area. In both cases, we consider thatcustomers buy from the cheapest facility and the same rulesare used for tie breaking in the lowest cost. While the profitmaximization problem for the entering firm always has optimalsolutions under mill pricing, this problem might not have anoptimal solution under delivered pricing. We show some discretizationresults and give procedures to find the full set of optimal,or -optimal, solutions to the problem under the two price policies.A comparison of results with the two price policies is givenby using an illustrative example.     

Fast and slow light generated simultaneously for up-down-link frequency converter applications

We firstly propose a new system for simultaneous fast and slow light generation using a soliton pulse propagating within the nonlinear micro-ring resonators. The nonlinear Kerr effect induces the spreading frequency bands within the micro-ring device, where the chaotic filtering characteristics can be employed using the appropriate micro-ring parameters. Results obtained have shown that the wide spreading of frequency bands can be generated and selected to form the optical wireless communication links. In this work, the selected down-link and up-link frequency bands are 500 MHz and 2 GHz, respectively. The proposed system can be implemented within the mobile telephone hand set, where the two different frequency carriers within the same frequency bands can be selected to form the up-down-link converters, which means that the frequency converter can be performed within a single system.     

海上运动辐射源单站纯方位无源定位分析

针对海上运动辐射源单站纯方位无源定位过程中辐射源运动参数对定位性能的影响进行分析,提出利用对目标的航向分析改进定位性能的方法,分析其性能改善程度及局限性。     

无线传感器网络节点定位技术综述

无线传感器网络在许多领域有着重要的科研和使用价值,网络中传感器节点自身定位可为无线传感器网络的很多应用提供基础信息,是重要研究方向之一.从无线传感器网络节点定位技术的研究意义与应用价值出发,介绍了节点定位技术的基本原理与方法,并讨论了定位算法的评价标准,最后对节点定位技术的发展方向进行了展望.     

高档住宅小区综合覆盖解决方案

从高档住宅小区网络建设的必要性、建设原理入手,详细讨论了小区中各功能区的无线覆盖方案.说明了天馈线选择、布线以及走线的注意事项.最后以实例论证了所提出的方案.     

无人值守无线传感器网络电源系统管理

无人值守无线传感器网络是当前通信和计算机领域研究的热点之一,具有十分广阔的应用前景。文章阐述了无线传感器网络的概念,以无线传感器网络的网络节点为研究对象,重点阐述了网络节点的基本结构和能耗状况,详细描述了无线传感器网络电源管理的微处理器控制以及软件控制流程。     

UWB无线通信关键技术及应用分析

UWB是目前最理想的低功耗、高带宽短距离无线通信技术。文中通过研究UWB无线通信的关键技术,指出其性能优点及局限性,阐明了UWB技术在军用和民用方面的应用前景。     

无线传感器网络中的网内信息处理技术

无线传感器网络（WSN）的传输技术发展迅速,但单纯的传输原始感知数据并不能满足传感器网络应用日益发展的智能化需求。传感器网络的网内信息处理技术在原始采集数据的基础上,将大量的信息处理和计算移植到传感网内部进行,从海量的、杂乱无章的、难以理解的原始数据中抽取并推导出对于某些特定的用户来说具有特定意义和判决参考价值的数据。网内信息处理技术能够降低网络数据传输量、节约能量资源、提高数据精度、减小传输延迟,以达到提高网络性能,高度契合用户信息需求的目标,是未来传感器网络技术发展的重要方向。     

车载AdHoc网络

车载自组织网络（VANET）作为移动自组织网络（MANET）的特殊子类,因其在智能交通和车载娱乐方面的广阔应用前景,目前受到业界的普遍关注。VANET的主要特点是车辆高速行驶、信道快速衰落、多普勒效应严重、网络拓扑变化快,由此将带来许多传输和组网的问题。