无线传感器网络存在易遭受恶意节点攻击而导致能量浪费和数据丢失等问题,为解决该问题,提出ETM-LEACH(energy and trust models based LEACH)算法。通过均衡网络能耗计算动态最优簇首数,引入能量判决因子、节点密度因子、节点信任因子...无线传感器网络存在易遭受恶意节点攻击而导致能量浪费和数据丢失等问题,为解决该问题,提出ETM-LEACH(energy and trust models based LEACH)算法。通过均衡网络能耗计算动态最优簇首数,引入能量判决因子、节点密度因子、节点信任因子改进选举簇首的阈值计算公式。加入绝对偏差过滤掉能量较低节点,采用信任模型引入多种状态信息计算直接信任值和间接信任值,筛选高可信节点。仿真结果表明,与现有协议相比,该协议能够有效降低节点能耗,优化网络部署,提高网络的安全性和可靠性。展开更多
Pb2＋ adsorption onto a soil by irrigation of sewage in the Pearl River Delta of South China was examined as a function of the reaction time, solution pH, initial lead concentration, organic matter （humic acid） and ...Pb2＋ adsorption onto a soil by irrigation of sewage in the Pearl River Delta of South China was examined as a function of the reaction time, solution pH, initial lead concentration, organic matter （humic acid） and competitive ions （Cu2＋）. The adsorption of Pb2＋ onto the soil was investigated on batch equilibrium adsorption experiments. Results show that the Pb2＋ adsorption on the soil is relatively rapid in the first 30 min and reaches equilibrium at 2 h, and the kinetics of the adsorption process on the soil is well characterized by the pseudo-second order reaction rate. Langmuir, Freundlich and Temkin isothermal models are fit for the adsorption of Pb2＋ onto the soil, and the maximum amount of Pb2＋ adsorption （Qm） is 7.47 mg/g. The amount of Pb2＋ adsorption increases with increasing the pH at the range of 1.2-4.5 and reaches a plateau at the range of 4.5-12. The presence of humic acid in soil decreases the adsorption of Pb2＋ onto the soil at solution pH of 8 since the negatively charged humic acid with Pb2＋ is difficult to be adsorbed on the negatively charged soil surface. The adsorption of Pb2＋ onto the soil also decreases in the presence of Cu2＋ due to file competition adsorption between Pb2＋ and Cu2＋.展开更多
文摘无线传感器网络存在易遭受恶意节点攻击而导致能量浪费和数据丢失等问题,为解决该问题,提出ETM-LEACH(energy and trust models based LEACH)算法。通过均衡网络能耗计算动态最优簇首数,引入能量判决因子、节点密度因子、节点信任因子改进选举簇首的阈值计算公式。加入绝对偏差过滤掉能量较低节点,采用信任模型引入多种状态信息计算直接信任值和间接信任值,筛选高可信节点。仿真结果表明,与现有协议相比,该协议能够有效降低节点能耗,优化网络部署,提高网络的安全性和可靠性。
基金Project(SK201109) supported by the Basic Scientific Study Funding from Institute of Hydrogeology and Environmental Geology,Chinese Academy of Geological SciencesProject(2010CB428806-2) supported by the National Basic Research Program of China
文摘Pb2＋ adsorption onto a soil by irrigation of sewage in the Pearl River Delta of South China was examined as a function of the reaction time, solution pH, initial lead concentration, organic matter （humic acid） and competitive ions （Cu2＋）. The adsorption of Pb2＋ onto the soil was investigated on batch equilibrium adsorption experiments. Results show that the Pb2＋ adsorption on the soil is relatively rapid in the first 30 min and reaches equilibrium at 2 h, and the kinetics of the adsorption process on the soil is well characterized by the pseudo-second order reaction rate. Langmuir, Freundlich and Temkin isothermal models are fit for the adsorption of Pb2＋ onto the soil, and the maximum amount of Pb2＋ adsorption （Qm） is 7.47 mg/g. The amount of Pb2＋ adsorption increases with increasing the pH at the range of 1.2-4.5 and reaches a plateau at the range of 4.5-12. The presence of humic acid in soil decreases the adsorption of Pb2＋ onto the soil at solution pH of 8 since the negatively charged humic acid with Pb2＋ is difficult to be adsorbed on the negatively charged soil surface. The adsorption of Pb2＋ onto the soil also decreases in the presence of Cu2＋ due to file competition adsorption between Pb2＋ and Cu2＋.
