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基于位置加权粒子群算法的WSNs能量优化 总被引:1,自引:0,他引:1
针对无线传感器网络经典分簇协议Leach存在能量消耗过大的问题,提出了一种基于LEACH的改进协议。该协议采用位置加权粒子群算法结合对惯性权值、学习因子的调整,优化LEACH协议的簇头选择机制,将节点剩余能量、簇间距离及簇头到基站的距离作为适应度函数因素,调节簇及选举簇头。仿真结果表明,改进的协议使整个网络能量消耗达到相对均衡,大大减少了节点能量消耗,从而延长了网络寿命。 相似文献
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《湖南工程学院学报(自然科学版)》2017,(1)
无线传感器网络是由部署在监测区域的大量传感器节点通过无线通信形成的自组织网络系统,传感器节点存在着电源能量、计算和通信能力有限等制约因素.为了均衡无线传感器网络中节点能量的消耗,延长无线传感器网络的工作寿命,提出一种基于模糊算法和最短路径的LEACH改进协议ILAFASP.该协议簇头选举时,采用模糊算法考虑相对节点剩余能量、相对集中度、相对节点度计算出每个节点的优先度,根据优先度选举簇头;在数据传送阶段,在源节点和基站之间建立最短多跳数据传输路径,减少簇头数据传输的能耗.仿真表明,该协议能够均衡节点能量的消耗,延长整个网络的工作寿命. 相似文献
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针对分簇路由协议稳定期和半数存活节点期过短,以及存在簇头选举不稳定和出现零簇头情况等问题进行改进,提出了一种基于簇头选举和节点位置优化的分簇路由算法。通过改进簇头选举流程,修改候选簇头节点集合的更新策略来保障簇头选举的稳定性。增加节点与基站的距离和节点与簇头的距离2个参数作为阈值调节因子,调节节点当选簇头的概率以均衡网络能耗延长稳定期和半数存活节点期。仿真结果表明,该算法能够保障每一轮选举出最佳数量的簇头并且避免零簇头情况的出现,同时在网络寿命上能有效延长无线传感器网络(WSN)的稳定期和半数节点死亡期。 相似文献
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为避免无线传感器网络的能量空洞问题, 延长无线传感器网络寿命, 提出一种新的基于双簇头的无线传感器网络非均匀分簇算法. 该算法综合考虑节点剩余能量和节点到基站的距离选举分簇簇头, 将无线传感器网络分为不同规模的簇; 为了减小规模较大簇的簇头节点收集与传输数据的负担, 在数据传输阶段构造基于改进最小二
叉树的数据传输路径. 实验结果表明, 该算法能够有效减小节点能量消耗, 可有效延长无线传感器网络的使用寿命. 相似文献
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《南京理工大学学报(自然科学版)》2014,(3)
针对传统的基于分簇的无线传感器网络(WSNs)信任评价模型中,簇头节点因负担大量的计算工作而降低网络生存时间的问题,提出一种通过人工免疫评估WSNs中节点信任值的方法。该方法运用阴性选择算法产生检测器,由基站根据检测器进行节点的信任检测,不需要簇头节点聚合成员节点的信任值,只要求簇头节点将成员节点的信任属性发送给基站,降低了簇头节点的负担,延长了WSNs的生存时间。仿真实验结果表明,该方法在延长网络生存时间的同时,与已有方法相比具有较高的检测率,在非信任节点数不超过40%时,检测率高于90%。 相似文献
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《南京理工大学学报(自然科学版)》2014,(3)
针对传统的基于分簇的无线传感器网络(WSNs)信任评价模型中,簇头节点因负担大量的计算工作而降低网络生存时间的问题,提出一种通过人工免疫评估WSNs中节点信任值的方法。该方法运用阴性选择算法产生检测器,由基站根据检测器进行节点的信任检测,不需要簇头节点聚合成员节点的信任值,只要求簇头节点将成员节点的信任属性发送给基站,降低了簇头节点的负担,延长了WSNs的生存时间。仿真实验结果表明,该方法在延长网络生存时间的同时,与已有方法相比具有较高的检测率,在非信任节点数不超过40%时,检测率高于90%。 相似文献
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将LEACH协议应用于环境复杂的煤矿巷道中存在不足,为了使LEACH协议更适用于煤矿巷道,对LEACH协议进行改进。首先,本文对选择簇头的阈值函数进行调整,加入节点剩余能量、位置信息以及邻节点数量因素;其次,改进建簇算法,节点通过计算与簇头节点和汇聚节点之间的距离来判断加入簇头还是与汇聚节点直接通信;最后,改进簇间通信机制,簇头之间通过多跳方式进行数据传输,并根据能量和距离信息选择下一跳簇头节点,提高簇间数据传输的可靠性。仿真实验表明,改进后的LEACH协议可以有效降低煤矿巷道无线传感器网络能耗,延长网络生命周期。 相似文献
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针对当前无线传感器网络分簇路由算法存在的节点能耗不平均、 节点过早死亡等缺陷, 提出一种改进低功耗自适应分簇(LEACH)的无线传感器网络路由算法. 首先针对无线传感器节点过早死亡的问题, 引入簇半径动态确定方式, 将整个无线传感器网络划分为多个不均匀的簇; 然后考虑簇首能量消耗过快的问题, 结合簇首所在位置和节点剩余能量选择每轮中的簇首; 最后改进数据传输机制保证节点能量消耗均衡, 并在MATLAB 2014平台上对无线传感器网络分簇路由算法的性能进行测试. 测试结果表明, 改进LEACH算法较好地解决了节点过早死亡的难题, 延长了无线传感器网络的寿命, 平衡了各节点能量消耗, 整个无线传感器网络的性能显著优于其他对比算法. 相似文献
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Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness. 相似文献
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Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly. 相似文献
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理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。 相似文献
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As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death. 相似文献
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Miao Maosheng 《华南师范大学学报(自然科学版)》2014,(6)
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula- 相似文献
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Yang Weitao 《华南师范大学学报(自然科学版)》2014,46(6):137-138
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re- 相似文献
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Bernard Kirtman 《华南师范大学学报(自然科学版)》2014,(6)
正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that 相似文献
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Michael Springborg 《华南师范大学学报(自然科学版)》2014,(6):136
For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the 相似文献
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《上海师范大学学报(自然科学版)》2014,(5):550
<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with 相似文献