WSN低功耗低时延路径式协同计算方法

针对云计算应用于无线传感器网络(Wireless Sensor Network,WSN)时延敏感型业务时存在的高传输时延问题,提出了一种WSN低功耗低时延路径式协同计算方法。该方法基于一种云雾网络架构开展研究,该架构利用汇聚节点组成雾计算层;在数据传输过程中基于雾计算层的计算能力分步骤完成任务计算,降低任务处理时延;由于汇聚节点计算能力较弱,时延降低将导致能耗增加,WSN工作寿命减短,为此提出能耗约束下的任务映射策略,并利用离散二进制粒子群优化(Binary Particle Swarm Optimization,BPSO)算法解决能耗约束下的时延优化问题。仿真结果表明,在相同的能耗约束下,对比其他算法,基于BPSO算法得出的映射方案能有效降低业务处理时延,满足时延敏感型业务的需求。     

基于改进正弦余弦算法的无线传感器节点部署优化

为了提高无线传感器网络（WSN）的性能，提出了一种基于改进正弦余弦算法（ESCA）的节点部署优化方法。首先，引入双曲正弦调节因子和动态余弦波权重系数，以平衡算法的全局探索与局部开发能力；然后，提出了一种基于拉普拉斯和高斯分布的变异策略，避免算法陷入局部最优。对于基准函数的优化实验结果表明，ESCA相比引力搜索算法、鲸鱼优化算法、基本正弦余弦算法（SCA）及其改进算法具有更高的收敛精度和收敛速度。最后，将ESCA应用于WSN节点部署优化，结果表明其优化覆盖率相比改进粒子群优化算法、外推人工蜂群算法、改进灰狼优化算法和自适应混沌量子粒子群算法分别提高了1.55个百分点、7.72个百分点、2.99个百分点和7.63个百分点，用更少节点便可达到相同目标精度。     

基于无线传感网的无人值守变电站监控系统

智能电网是当今国家重点建设项目之一,智能变电站是智能电网的重要组成部分。实现智能变电站需要实现变电站的无人值守监控系统。针对传统变电站监控系统的不足,提出了一套基于无线传感网通信协议的利用各种传感器采集现场数据和视频采集处理的无人值守的监控系统。该系统可以极大地解放管理人员,提高工作效率,降低控制成本。     

Application of robotics in onshore oil and gas industry—A review Part I

With ever increasing global demand and depleting resources for fossil fuels, oil and gas industry is now positively looking for advanced robotic solutions to increase their productivity and safety. With time easy resources of the fossil fuels are shrinking and newly searched reservoirs, to feed supply demands of global consumption, are mostly located in extreme environmental conditions such as hot deserts, deep water and arctic zone etc. Production of the fossil fuels, in such inhospitable environmental conditions, poses difficult challenges to health, safety and environment (HSE). Tragic incidents like Exxon Valdez and Deepwater Horizon oil spills are examples of such challenges. Therefore, oil and gas industry has lot to learn from successful implementation of robotics and automation for dull, dirty and dangerous (3D) tasks of manufacturing industry. Most of the robotics technologies, currently used in the oil and gas industry, are mainly focused on inspection, maintenance and repair (IMR) of plant facilities with higher frequency and accuracy. Fundamental idea, involved in the automatization of these processes, is based on the principle of teleoperation with skilled operator. Automation of 3D tasks not only improves HSE standards but also lead to much needed economic efficiency by reducing production cycle, floor space and number of staff members required for continuous inspection and manipulation of plant facilities. Considering the risks involved in this industry usage of completely autonomous robots, first without achieving very high reliability, is still a far fetch choice. Therefore, semi-autonomous robots, where actions are performed by robots but cognitive decisions are still taken by skilled operator, is an excellent choice for this industry as a near future solution. In the onshore oil and gas industry robotic solutions are used both in upstream and downstream processes, such as site survey, drilling, production and transportation, mainly focused in the form of in-pipe inspection robots (IPIRs), tank inspection robots (TIRs), unmanned aerial vehicles (UAVs) and wireless sensor networks (WSNs) etc. This paper presents the state of art robotic solutions currently used in onshore oil and gas facilities.     

基于FAHP的机械振动WSN均衡拓扑构建方法

针对机械振动无线传感器网络因拓扑不均衡导致传输时延和网络传输能耗增加的问题,提出了一种基于模糊层次分析(fuzzy analytic hierarchy process,简称FAHP)的均衡拓扑构建方法,该方法由构建模糊判断矩阵和计算权重向量组成。首先,传感器节点进行簇内通信获取信标广播信息,将信标节点网络决策因子统一量纲化,利用网络决策因子构建模糊判断矩阵;其次,检验模糊判断矩阵一致性,采用行和归一化处理或拉格朗日最小二乘法计算权重向量;最后,传感器节点通过权重向量计算出各个信标节点综合权值,关联最优信标节点为父节点加入网络,将提出的模糊层次分析拓扑构建方法与基于链路质量单准则构建网络拓扑机制进行对比。实验结果表明,该方法能有效改善传输时延和机械振动无线传感器节点网络寿命。     

低开销负载均衡的改进型TORA协议

针对无线传感器网络拓扑快速变化、链路易拥塞断开，存在路由开销大、负载不均衡、网络生命周期短等问题，提出低开销负载均衡的改进型TORA（TORA-p）。通过定义网络变化率参数，自适应调整互联网封装协议（IMEP）中OBM包的最大重发次数，减少不必要的路由维护开销；同时，结合MAC层信息，定义链路可用性优化选路方式，自动平衡网络负载，避免关键路径和节点负载过重而过早死亡和断开。使用truetime2.0平台设定特定的仿真环境，对TORA-p算法的性能进行了详细比较分析，结果表明：TORA-p均衡了网络负载，提升了网络生命周期，同时也减少了路由开销和延时，展现出了较好的数据传输能力。     

Feasibility and modelling for convergence of optical-wireless network – A review

Now a days, the convergence of wireless and optical network gaining popularity to enhance the data carrying capacity, QoS and to support future multimedia applications. The queue theory plays an important role for analytically evaluating such converged networks. In the everyday state of affairs, queue phenomena are observed in the several situations like the health clinic, railway reservation system, automobile laundry centre, bank cash counter, call centre, etc. Similarly, the phenomenon of congestion is ascertained in the telephone network, computer network, communication systems and the Internet wherever nonstop enhancements need to be created to stay up with the quickly growing demand. The subsistence of these adverse clogging effects has lead toward the improvement of queuing theory-based statistical models. Therefore, these queues based statistical models answering to optimising queries corresponding to the way for assigning resources in converged optical and wireless networks. During this paper, a review on the role of the queuing model in wireless & optical communication is presented that concentrate on the present and future aspects of research.     

D-FICCA: A density-based fuzzy imperialist competitive clustering algorithm for intrusion detection in wireless sensor networks

Owing to the scattered nature of Denial-of-Service attacks, it is tremendously challenging to detect such malicious behavior using traditional intrusion detection systems in Wireless Sensor Networks (WSNs). In the current paper, a hybrid clustering method is introduced, namely a density-based fuzzy imperialist competitive clustering algorithm (D-FICCA). Hereby, the imperialist competitive algorithm (ICA) is modified with a density-based algorithm and fuzzy logic for optimum clustering in WSNs. A density-based clustering algorithm helps improve the imperialist competitive algorithm for the formation of arbitrary cluster shapes as well as handling noise. The fuzzy logic controller (FLC) assimilates to imperialistic competition by adjusting the fuzzy rules to avoid possible errors of the worst imperialist action selection strategy. The proposed method aims to enhance the accuracy of malicious detection. D-FICCA is evaluated on a publicly available dataset consisting of real measurements collected from sensors deployed at the Intel Berkeley Research Lab. Its performance is compared against existing empirical methods, such as K-MICA, K-mean, and DBSCAN. The results demonstrate that the proposed framework achieves higher detection accuracy 87% and clustering quality 0.99 compared to existing approaches.     

Distributed algorithm for target localization in wireless sensor networks using RSS and AoA measurements

This paper addresses target localization problem in a cooperative 3-D wireless sensor network (WSN). We employ a hybrid system that fuses distance and angle measurements, extracted from the received signal strength (RSS) and angle-of-arrival (AoA) information, respectively. Based on range measurement model and simple geometry, we derive a novel non-convex estimator based on the least squares (LS) criterion. The derived non-convex estimator tightly approximates the maximum likelihood (ML) one for small noise levels. We show that the developed non-convex estimator is suitable for distributed implementation, and that it can be transformed into a convex one by applying a second-order cone programming (SOCP) relaxation technique. We also show that the developed non-convex estimator can be transformed into a generalized trust region sub-problem (GTRS) framework, by following the squared range (SR) approach. The proposed SOCP algorithm for known transmit powers is then generalized to the case where the transmit powers are different and not known. Furthermore, we provide a detailed analysis of the computational complexity of the proposed algorithms. Our simulation results show that the new estimators have excellent performance in terms of the estimation accuracy and convergence, and they confirm the effectiveness of combining two radio measurements.     

基于无线传感器网络的煤矿瓦斯监测系统软件的研究

采用Visual C#设计的煤矿瓦斯监测监控系统的监控软件,实现对基于无线传感器网络的煤矿瓦斯监测系统的数据库保存,实时数据监测显示,历史数据查询统计,预警曲线显示,数据报表显示功能。该监控软件具有稳定性好、监测精度高、成本低和操作简单的特点。使用该监控软件可以实时监测煤矿的安全现状,有效减少煤矿井下瓦斯事故的发生。