一种基于信号机制的能量感知地理路由算法

在实际的无线传感器网络中,由于路由空洞的存在,采用边缘转发机制的地理路由算法容易使空洞边缘的节点由于负载较重,能量快速消耗从而过早的死亡,导致空洞进一步的扩大．为了使网络负载更加均衡,延长网络生命周期,提出了一种基于能量信号机制的地理路由算法SIENGR ．SIENGR将节点的初始能量划分3个能量区间,并用能量信号来标识节点的剩余能量所处的能量区间．SIENGR算法的边缘转发机制结合节点的能量信号,利用空洞边界节点的所有平面邻居节点来轮流承担边缘转发的数据量,使产生的路由能够根据节点能耗的情况,自适应地避开空洞边缘能量较少的热区节点,均衡热区附近节点的能量消耗,防止空洞扩大．仿真结果验证了SIENGR算法在网络生命周期、网络能耗均衡、数据包到达率等指标上的性能．     

一种基于数据融合的WSN节点部署策略

采用非均匀的方法部署节点,提出了一种基于数据融合的节点部署策略.针对节点数据采集率恒定的圆形网络场景,根据避免能量空洞以及降低数据冗余度的思想部署传感器节点,通过该策略使得网络达到次级能耗均衡.仿真结果表明该方法能够缓解能量空洞问题,延长网络生命周期.     

混合传感器网络中基于向量代数的覆盖补偿算法

针对混合传感器网络中,能量耗尽造成的覆盖空洞与休眠冗余节点能量剩余可能并存的矛盾现象,提出一种基于向量代数的移动节点覆盖补偿方法.算法包含所有可能参与补偿的冗余节点对各自位移量的计算方法,空洞边缘节点在平衡节点剩余能量的基础上,对最佳冗余节点的选择启用策略,保证网络能充分利用遗留能量资源的同时实现完全覆盖补偿.实验分析表明,本算法在平均移动距离、能量开销等方面均优于COA算法.     

基于三维胞元空间的能量高效性多通道协作路由算法

针对无线传感器网络中因空洞引起路由效率降低的问题,该文提出了基于3维胞元空间的能量高效性多通道协助路由算法(3D-EEMCR)。该算法根据能量损耗模型,权衡考虑节点的剩余能量和位置信息来选举胞父节点,从而平衡网络能耗;另外,算法采用主通道和辅助通道相互协助的周边路由模式完成空洞区域的路由。仿真结果表明,3D-EEMCR相比3D-GPR(Grid Position-based Routing)和3D-CSR(Cell Space Routing)能够有效提高消息包的发送率,降低网络的平均能耗,延长网络的生存周期。     

基于DE的WSN能量空洞问题最优发射半径选取

针对无线传感器网络能量空洞问题,通过对具有节点均匀且呈环状分布的WSN相关模型进行了分析。并在此基础上,将能量空洞问题转化为不同发射半径下,能量消耗值最大节点的问题,从而确定了具有不连续、不可导、多峰值特点的优化目标函数。最终采用CoDE算法求解该优化问题,并通过仿真实例验证了,该方法的正确性与可行性。     

认知网络中基于簇结构的拓扑形成算法

在多跳的认知无线网络中,网络的拓扑发现算法都必须极其灵活以适应于环境内频谱空洞的改变。研究了认知无线电网络的基本特点,结合Ad-hoc网络簇的概念,在得到认知设备的感知结果的基础上,提出了一种适合于认知无线电网络的有效的拓扑形成算法。在提出的算法中,将可用的频谱空洞信息和节点的能量信息综合考虑,是一个组合的优化算法。     

无线传感器网络能量均衡路由博弈算法

针对无线传感器网络节点能耗不均匀,容易形成网络分区的问题,提出了一种基于博弈论的无线传感网络路由选择策略,建立传感器节点之间以剩余能量为效用的博弈模型,求解并确定节点剩余能量最优的路由。仿真结果表明,所提出的路由选择策略可以有效地最大化节点的剩余能量,同时当该模型处于纳什均衡解时,每条路径的能耗处于均衡状态,有效地利用了传感器节点的能量资源,避免了网络能量的空洞,延长了网络的生命周期。     

WSNs中基于粒子群优化的信宿移动路径规划算法

感测数据,再将数据传输至信宿是无线传感网络(WSNs)中节点的首要任务。传感节点由电池供电,它们的多数能量用于传输数据,越靠近信宿的节点,传输的数据量越大。因此,这些节点的能耗速度快,容易形成能量-空洞问题。而通过移动信宿收集数据能够缓解能量-空洞问题。为此,提出基于粒子群优化的信宿移动路径规划(PSO-RPS)算法。PSO-RPS算法结合数据传递时延和信息速率两项信息选择驻留点,并利用粒子群优化算法选择最优的驻留点,进而构建时延有效的信宿收集数据的路径。仿真结果表明,提出的PSO-RPS算法有效地控制路径长度,缩短了收集数据的时延。     

MANET中一种具有能量意识的无信标地理路由算法

 地理路由具有有效的传输性能和良好的可扩展能力,是当前移动Ad Hoc网络路由算法中的一个研究热点. 在许多实际场合下,网络中的节点能量有限并且难以补充,所以合理调整节点之间的能量消耗成为提高网络寿命的一种重要手段. 本文针对贪婪转发和空洞解决方案中存在的节点能量消耗不平衡的问题,提出了一种具有能量意识的无信标地理路由算法EBGR (Energy-Aware and Beaconless Geographic Routing). 该算法包括两个模式：贪婪竞争策略和空洞解决策略. 在贪婪竞争策略中,源节点或中继节点（即上游节点）广播数据包,位于数据包转发域内具有最小动态转发延迟的节点（即下游节点）转发数据包,其余候选节点侦听到该广播包后,自动放弃转发该数据包. 当遇到节点空洞时,将角度和能量信息同时加入到转发节点的动态延迟计算中,从而在数据包转发过程中有效地避绕空洞和平衡节点间的能量消耗. 仿真结果表明,与已有的BLR和GEAR等典型地理路由算法相比,平均投递率提高2%到4%;平均网络寿命提高了10%到20%.     

具有能量和位置意识基于ACO的WSN路由算法

通过融合传感器节点的剩余能量和地理位置信息,设计一种具有传感器节点能量和地理位置意识的基于蚁群优化方法的无线传感器网络路由算法(ELACO);针对路由空洞现象,提出一种路由回退机制,提高了路由搜索成功率.仿真结果表明,ELACO算法具有很高的路由查寻成功率,能够更好地均衡传感器节点能量消耗,从而延长网络使用寿命.     

Relocation routing for energy balancing in mobile sensor networks

Wireless sensor networks (WSNs) have been widely investigated in the past decades because of its applicability in various extreme environments. As sensors use battery, most works on WSNs focus on energy efficiency issues (e.g., local energy balancing problems) in statically deployed WSNs. Few works have paid attention to the global energy balancing problem for the scenario that mobile sensor nodes can move freely. In this paper, we propose a new routing protocol called global energy balancing routing protocol (GEBRP) based on an active network framework and node relocation in mobile sensor networks. This protocol achieves global energy efficiency by repairing coverage holes and replacing invalid nodes dynamically. Simulation and experiment results demonstrate that the proposed GEBRP achieves superior performance over the existing scheme. In addition, we analyze the delay performance of GEBRP and study how the delay performance is affected by various system parameters.Copyright © 2013 John Wiley & Sons, Ltd.     

传感器网络簇间通信自适应节能路由优化算法

提出了一种用于无线传感器网络簇间通信的自适应节能路由优化算法。网络中以总体通信能耗最小为首要原则建立端到端之间的路由,并对簇间通信提出了一种优化算法,使得簇首之间相互通信时,可以在直接、中继以及协作3种不同方式中自适应地选择最节能的通信方式。所提出的路由算法可确保源节点与基站通信过程中选择到最优或次优的节能路由,并可降低由于通信覆盖盲区造成的通信中断的概率。仿真结果表明,与其他传感器网络路由算法相比,所提出的路由算法在相同吞吐量和误码率前提下每一轮都消耗更少的能量,并且在不同的节点密度下都可有效地延长网络的生命周期和工作时间。     

纤锌矿GaN/AlxGa1-xN量子阱中激子能量

考虑了纤锌矿GaN/Al<,x>Ga<,1-x>N量子阱(QW)材料中空穴带质量和光学声子模的各向异性以及声子频率随波矢变化的效应,采用改进的LLP变分法计算了纤锌矿氮化物QW中激子的基态能量和结合能.给出了激子的基态能量和结合能随着QW宽度和Al组分变化的函数关系,并对闪锌矿和纤锌矿GaN/Al<0.3>Ga<,0....     

Energy efficient watchman based flooding algorithm for IoT-enabled underwater wireless sensor and actor networks

In the task of data routing in Internet of Things enabled volatile underwater environments, providing better transmission and maximizing network communication performance are always challenging. Many network issues such as void holes and network isolation occur because of long routing distances between nodes. Void holes usually occur around the sink because nodes die early due to the high energy consumed to forward packets sent and received from other nodes. These void holes are a major challenge for I-UWSANs and cause high end-to-end delay, data packet loss, and energy consumption. They also affect the data delivery ratio. Hence, this paper presents an energy efficient watchman based flooding algorithm to address void holes. First, the proposed technique is formally verified by the Z-Eves toolbox to ensure its validity and correctness. Second, simulation is used to evaluate the energy consumption, packet loss, packet delivery ratio, and throughput of the network. The results are compared with well-known algorithms like energy-aware scalable reliable and void-hole mitigation routing and angle based flooding. The extensive results show that the proposed algorithm performs better than the benchmark techniques.     

Distributed fuzzy logic based energy‐aware and coverage preserving unequal clustering algorithm for wireless sensor networks

In an energy‐constrained wireless sensor networks (WSNs), clustering is found to be an effective strategy to minimize the energy depletion of sensor nodes. In clustered WSNs, network is partitioned into set of clusters, each having a coordinator called cluster head (CH), which collects data from its cluster members and forwards it to the base station (BS) via other CHs. Clustered WSNs often suffer from the hot spot problem where CHs closer to the BS die much early because of high energy consumption contributed by the data forwarding load. Such death of nodes results coverage holes in the network very early. In most applications of WSNs, coverage preservation of the target area is a primary measure of quality of service. Considering the energy limitation of sensors, most of the clustering algorithms designed for WSNs focus on energy efficiency while ignoring the coverage requirement. In this paper, we propose a distributed clustering algorithm that uses fuzzy logic to establish a trade‐off between the energy efficiency and coverage requirement. This algorithm considers both energy and coverage parameters during cluster formation to maximize the coverage preservation of target area. Further, to deal with hot spot problem, it forms unequal sized clusters such that more CHs are available closer to BS to share the high data forwarding load. The performance of the proposed clustering algorithm is compared with some of the well‐known existing algorithms under different network scenarios. The simulation results validate the superiority of our algorithm in network lifetime, coverage preservation, and energy efficiency.     

Routing design avoiding energy holes in underwater acoustic sensor networks

Interest in underwater acoustic sensor networks (UW‐ASNs) has rapidly increased with the desire to control the large portion of the world covered by oceans. Energy efficiency is one of the major concerns in UW‐ASNs due to the limited energy budget of the underwater sensor nodes. In this paper, we tackle the problem of energy holes in UW‐ASNs while taking into consideration the unique characteristics of the underwater channel. We prove that we can evenly distribute the transmission load among sensor nodes provided that sensors adjust their communication range when they send or forward the periodically generated data. In particular, we propose a balanced routing strategy along with the associated deployment pattern that meticulously determines the load weight for each possible next hop that leads to fair energy consumption among all underwater sensors. Consequently, the energy holes problem is overcome, and hence, the network lifetime is improved. To the best of our knowledge, this is the first work that addresses the energy hole problem in UW‐ASNs. Copyright © 2016 John Wiley & Sons, Ltd.     

通信网络能耗分析与节能技术应用探究

在本文中,笔者从通信网络能耗的特征及其所需的环境入手,就当前通信设备、基站及电源的能耗状况进行总结,从而综合分析能耗分布,进而指出有效的节能措施。依托于此,笔者提出构建通信机房节能改造方案与基站节能方案。这些方案对于我国通信企业的节能现状改良具有很强的现实意义。通信企业应加大能耗方面的管理与控制工作,综合运用多种信息化技术,结合自身的实际状况,逐步构建起节能型的通信网络,只有这样才能够实现其自身的可持续发展,有效降低运营成本。     

Effect of the relationship between the energy levels of host and guest on EL performance of phosphorescence organic light-emitting diodes

In this work, we used five different fluorescent hosts and six phosphorescent guests to study the effect of the relationship between the energy levels of host and guest on the EL performance of phosphorescence organic light-emitting diodes (PHOLEDs). The experimental results show clearly that the difference between triplet energy levels of the used host and guest plays an important role, and the electron and hole injection barriers, respectively, from electron-transporting layer (ETL) and hole-transporting layer (HTL) into emitting layer (EML) and the mobility of ETL also have a certain influence. It can be seen that the triplet energy level of hosts should be higher than that of guests and the distance between them is as close as possible, ensuring the effective energy transfer from hosts to guests. Furthermore, it is also necessary to have low injection barriers into EML for electrons and holes, and high electron mobility of ETL, which guarantee electrons and holes injected effectively and evenly. This further explains the fundamental reason why the fabrication of high efficiency PHOLEDs must optimize the host, guest and match transporting layers. Our studies will help to establish better design rules for host-guest systems to achieve high performance PHOLEDs.     

风能、太阳能电网设计

21世纪,能源领域将重点放在核能、风能及太阳能等领域,各个国家也都相继提出自己的优惠政策,因此设计出切实可行的新能源运行方案是非常之必要的。基于此,阐述了风能、太阳能发电、储能、并网的关联可行方案,全部采用环保无污染产品作为基础搭建。     

通信网络能效度量及优化方法

虽然网络在提高众多行业能效的过程中起到了非常重要的作用,但随着互联网用户、业务和应用的迅猛发展,网络能耗逐年增加,已经威胁网络运营商的可持续发展。主要探讨了网络运营企业面临的能耗风险,介绍了能耗度量和优化方法研究方面取得的进展。最后,总结了在新型网络研究中提高网络能效的相应事宜。