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41.
针对无线传感器网络在对移动目标节点覆盖过程中出现网络能量快速消耗问题,提出了一种基于联合节点行为策略的覆盖算法。根据网络模型建立传感器节点与目标节点从属关系,确定覆盖关联模型;利用概率理论求解邻居节点冗余覆盖度,确定最少传感器节点数量;给出了邻居节点覆盖期望值的求解方法;仿真实验表明,该算法与其他算法在网络覆盖率和网络生存周期两个性能指标上均提升了12.39%和15.01%,从而验证了算法的有效性。 相似文献
42.
Ning Wang Yinya Li Guoqing Qi Andong Sheng 《International Journal of Adaptive Control and Signal Processing》2019,33(7):1174-1188
This paper investigates the state estimation issue for a class of wireless sensor networks (WSNs) with the consideration of limited energy resources. First, a multirate estimation model is established, and then, a new event‐triggered two‐stage information fusion algorithm is developed based on the optimal fusion criterion weighted by matrices. Compared with the existing methods, the presented fusion algorithm can significantly reduce the communication cost in WSNs and save energy resources of sensors efficiently. Furthermore, by presetting a desired containment probability over the interval [0,1] with the developed event‐triggered mechanism, one can obtain a suitable compromise between the communication cost and the estimation accuracy. Finally, a numerical simulation for the WSN tracking system is given to demonstrate the effectiveness of the proposed method. 相似文献
43.
Huai‐Ning Wu Xiao‐Wei Zhang 《International Journal of Adaptive Control and Signal Processing》2019,33(10):1552-1566
This paper studies an enhanced state estimation problem of distributed parameter processes modeled by a linear parabolic partial differential equation using mobile sensors. The proposed estimation scheme contains a state estimator and the guidance of mobile sensors, where the spatial domain is decomposed into multiple subdomains according to the number of sensors and each sensor is capable of moving within the respective subdomain. The state estimator is desired to make the state estimation error system exponentially stable while providing an performance bound. The mobile sensor guidance is used to enhance the transient performance of the error system. By the Lyapunov direct technique, an integrated design of state estimator and mobile sensor guidance laws is developed in the form of bilinear matrix inequalities (BMIs) to meet the desired design objectives. Moreover, to make the performance bound as small as possible, a suboptimal enhanced state estimation problem is formulated as a BMI optimization one, which can be solved via an iterative linear matrix inequality algorithm. Finally, numerical simulations are given to show the effectiveness of the proposed method. 相似文献
44.
Andrej Paul Bertram Schwind Christian Weinberger Michael Tiemann Thorsten Wagner 《Advanced functional materials》2019,29(43)
A nanocomposite material based on copper(II) oxide (CuO) and its utilization as a highly selective and stable gas‐responsive electrical switch for hydrogen sulphide (H2S) detection is presented. The material can be applied as a sensitive layer for H2S monitoring, e.g., in biogas gas plants. CuO nanoparticles are embedded in a rigid, nanoporous silica (SiO2) matrix to form an electrical percolating network of low conducting CuO and, upon exposure to H2S, highly conducting copper(II) sulphide (CuS) particles. By steric hindrance due to the silica pore walls, the structure of the network is maintained even though the reversible reaction of CuO to CuS is accompanied by significant volume expansion. The conducting state of the percolating network can be controlled by a variety of parameters, such as temperature, electrode layout, and network topology of the porous silica matrix. The latter means that this new type of sensing material has a structure‐encoded detection limit for H2S, which offers new application opportunities. The fabrication process of the mesoporous CuO@SiO2 composite as well as the sensor design and characteristics are described in detail. In addition, theoretical modeling of the percolation effect by Monte‐Carlo simulations yields deeper insight into the underlying percolation mechanism and the observed response characteristics. 相似文献
45.
46.
Weidong Fang Wuxiong Zhang QianQian Zhao Xiaohong Ji Wei Chen Biruk Assefa 《计算机、材料和连续体(英文)》2019,61(2):583-599
As an Industrial Wireless Sensor Network (IWSN) is usually deployed in a harsh or unattended environment, the privacy security of data aggregation is facing more and more challenges. Currently, the data aggregation protocols mainly focus on improving the efficiency of data transmitting and aggregating, alternately, the aim at enhancing the security of data. The performances of the secure data aggregation protocols are the trade-off of several metrics, which involves the transmission/fusion, the energy efficiency and the security in Wireless Sensor Network (WSN). Unfortunately, there is no paper in systematic analysis about the performance of the secure data aggregation protocols whether in IWSN or in WSN. In consideration of IWSN, we firstly review the security requirements and techniques in WSN data aggregation in this paper. Then, we give a holistic overview of the classical secure data aggregation protocols, which are divided into three categories: hop-by-hop encrypted data aggregation, end-to-end encrypted data aggregation and unencrypted secure data aggregation. Along this way, combining with the characteristics of industrial applications, we analyze the pros and cons of the existing security schemes in each category qualitatively, and realize that the security and the energy efficiency are suitable for IWSN. Finally, we make the conclusion about the techniques and approach in these categories, and highlight the future research directions of privacy preserving data aggregation in IWSN. 相似文献
47.
For the redundancy coverage of nodes leads to the phenomenon of low energy efficiency,Non-cooperative game theory was used to solve it.A revenue function was proposed,which considering the coverage of nodes and the residual energy.The lifetime of the node and network path gain were applied to revenue function.The network topology was built by nodes with the appropriate work strategy.Control algorithm coverage in wireless sensor network was proposed based on Non-cooperative game theory.A Nash equilibrium between the coverage rate and the residual energy was proved,and the return function converged to the Pareto optimal.Experiments show that the algorithm can provide reasonable coverage of network nodes and ensure energy efficiency. 相似文献
48.
Several three-party password authenticated key exchange (3-PAKE) protocols have recently been proposed for heterogeneous wireless sensor networks (HWSN). These are efficient and designed to address security concerns in ad-hoc sensor network applications for a global Internet of Things framework, where a user may request access to sensitive information collected by resource-constrained sensors in clusters managed by gateway nodes. In this paper we first analyze three recently proposed 3-PAKE protocols and discuss their vulnerabilities. Then, based on Radio Frequency Identification technologies we propose a novel 3-PAKE protocol for HWSN applications, with two extensions for additional security features, that is provably secure, efficient and flexible. 相似文献
49.
摘要:提出了一种基于纸基底的喷墨印刷无芯片RFID湿度传感器,通过遗传算法与射频仿真软件HFSS相结合,对常规开口环谐振器结构进行分布式加载,得到目标频率为245 GHz的谐振特性良好的传感器模型;采用DMP3000型材料打印机,在不同纸基底上喷墨印刷银墨水制作传感器,以纸张本身的吸水性实现湿度传感;研究不同纸基底对湿度传感器感湿灵敏度和恢复度的影响。结果表明,柯达相纸传感器的灵敏度最高,高湿灵敏度可达到8 MHz%RH,双铜纸湿度传感器恢复度高且恢复时间短,仅为2 min;两种基底湿度传感器皆有较好的一致性、中长期稳定性,且湿敏特性在20℃~30℃范围内受温度影响较小。对纸基湿度传感器的感湿机理进行了分析,纸主要成分纤维素表面的羟基与吸附的水分子作用形成氢键,改变了基底的介电参数,传感器的湿敏特性与纸的成分和结构有关。 .txt 相似文献
50.