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Topology control of tactical wireless sensor networks using energy efficient zone routing 被引量:4
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作者 Preetha Thulasiraman Kevin A. White 《Digital Communications and Networks》 SCIE 2016年第1期1-14,共14页
The US Department of Defense (DoD) routinely uses wireless sensor networks (WSNs) for military tactical communications. Sensor node die-out has a significant impact on the topology of a tactical WSN. This is probl... The US Department of Defense (DoD) routinely uses wireless sensor networks (WSNs) for military tactical communications. Sensor node die-out has a significant impact on the topology of a tactical WSN. This is problematic for military applications where situational data is critical to tactical decision making. To increase the amount of time all sensor nodes remain active within the network and to control the network topology tactically, energy efficient routing mechanisms must be employed. In this paper, we aim to provide realistic insights on the practical advantages and disadvantages of using established routing techniques for tactical WSNs. We investigate the following established routing algorithms: direct routing, minimum transmission energy (MTE), Low Energy Adaptive Cluster Head routing (LEACH), and zone clustering. Based on the node die out statistics observed with these algorithms and the topological impact the node die outs have on the network, we develop a novel, energy efficient zone clustering algorithm called EZone. Via extensive simulations using MATLAB, we analyze the effectiveness of these algorithms on network performance for single and multiple gateway scenarios and show that the EZone algorithm tactically controls the topology of the network, thereby maintaining significant service area coverage when compared to the other routing algorithms. 展开更多
关键词 ROUTING Energy efficiency Wiretess sensor net- works ZONES Topology control
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IUKF neural network modeling for FOG temperature drift 被引量:4
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作者 Feng Zha Jiangning Xu +1 位作者 Jingshu Li Hongyang He 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2013年第5期838-844,共7页
A novel neural network based on iterated unscented Kalman filter (IUKF) algorithm is established to model and com- pensate for the fiber optic gyro (FOG) bias drift caused by temperature. In the network, FOG tempe... A novel neural network based on iterated unscented Kalman filter (IUKF) algorithm is established to model and com- pensate for the fiber optic gyro (FOG) bias drift caused by temperature. In the network, FOG temperature and its gradient are set as input and the FOG bias drift is set as the expected output. A 2-5-1 network trained with IUKF algorithm is established. The IUKF algorithm is developed on the basis of the unscented Kalman filter (UKF). The weight and bias vectors of the hidden layer are set as the state of the UKF and its process and measurement equations are deduced according to the network architecture. To solve the unavoidable estimation deviation of the mean and covariance of the states in the UKF algorithm, iterative computation is introduced into the UKF after the measurement update. While the measure- ment noise R is extended into the state vectors before iteration in order to meet the statistic orthogonality of estimate and mea- surement noise. The IUKF algorithm can provide the optimized estimation for the neural network because of its state expansion and iteration. Temperature rise (-20-20℃) and drop (70-20℃) tests for FOG are carried out in an attemperator. The temperature drift model is built with neural network, and it is trained respectively with BP, UKF and IUKF algorithms. The results prove that the proposed model has higher precision compared with the back- propagation (BP) and UKF network models. 展开更多
关键词 fiber optic gyro (FOG) temperature drift neural net- work iterated unscented Kalman filter (IUKF).
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Optimization of Laser Ablation Technology for PDPhSM Matrix Nanocomposite Thin Film by Artificial Neural Networks-particle Swarm Algorithm 被引量:3
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作者 唐普洪 宋仁国 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2010年第2期188-193,共6页
A new thermal ring-opening polymerization technique for 1, 1, 3, 3-tetra-ph enyl-1, 3-disilacyclobutane (TPDC) based on the use of metal nanoparticles produced by pulsed laser ablation was investigated. This method ... A new thermal ring-opening polymerization technique for 1, 1, 3, 3-tetra-ph enyl-1, 3-disilacyclobutane (TPDC) based on the use of metal nanoparticles produced by pulsed laser ablation was investigated. This method facilitates the synthesis of polydiphenysilylenemethyle (PDPhSM) thin film, which is difficult to make by conventional methods because of its insolubility and high melting point. TPDC was first evaporated on silicon substrates and then exposed to metal nanoparticles deposition by pulsed laser ablation prior to heat treatment.The TPDC films with metal nanoparticles were heated in an electric furnace in air atmosphere to induce ring-opening polymerization of TPDC. The film thicknesses before and after polymerization were measured by a stylus profilometer. Since the polymerization process competes with re-evaporation of TPDC during the heating, the thickness ratio of the polymer to the monomer was defined as the polymerization efficiency, which depends greatly on the technology conditions. Therefore, a well trained radial base function neural network model was constructed to approach the complex nonlinear relationship. Moreover, a particle swarm algorithm was firstly introduced to search for an optimum technology directly from RBF neural network model. This ensures that the fabrication of thin film with appropriate properties using pulsed laser ablation requires no in-depth understanding of the entire behavior of the technology conditions. 展开更多
关键词 nanocomposite thin film pulsed laser deposition(PLD) artificial neural net- works(ANN) particle swarm optimization (PSO)
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Network selection based on available lin bandwidth in multi-access networks
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作者 Kiran Ahuja Brahrnjit Singh Rajesh Khanna 《Digital Communications and Networks》 SCIE 2016年第1期15-23,共9页
One of the important aspects of seamless communication for ubiquitous computing is the dynamic selection of the best access network for a multimodal device in a heterogeneous wireless environment. In this paper, we co... One of the important aspects of seamless communication for ubiquitous computing is the dynamic selection of the best access network for a multimodal device in a heterogeneous wireless environment. In this paper, we consider available bandwidth as a dynamic parameter to select the network in heterogeneous environments. A bootstrap approximation based technique is firstly utilized to estimate the available bandwidth and compare it with hidden Markov model based estimation to check its accuracy. It is then used for the selection of the best suitable network in the heterogeneous environment consisting of 2G and 3G standards based wireless networks. The proposed algorithm is implemented in temporal and spatial domains to check its robustness. The numerical results show that the proposed algorithm gives improved performance in terms of estimation error (less than 15%), overhead (varies from 0.45% to 72.91%) and reliability (approx. 99%)as compared to the existing algorithm. 展开更多
关键词 2G 3G Heterogeneous net- works Bootstrap approximation Avaitabie bandwidth
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精神分裂症首次发病患者额顶网络功能连接与面孔情绪识别能力的关系 被引量:5
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作者 吕一丁 姚晶晶 +2 位作者 赵晓鑫 李元 谢世平 《临床精神医学杂志》 2016年第6期372-375,共4页
目的:探讨首发精神分裂症患者在静息状态下额顶网络的功能连接特点,及其与面孔情绪识别能力的相关性。方法:对37例首发未用药的精神分裂症患者(患者组)和30名年龄、性别、利手、受教育程度与患者相匹配的健康者(正常对照组)进行静息态... 目的:探讨首发精神分裂症患者在静息状态下额顶网络的功能连接特点,及其与面孔情绪识别能力的相关性。方法:对37例首发未用药的精神分裂症患者(患者组)和30名年龄、性别、利手、受教育程度与患者相匹配的健康者(正常对照组)进行静息态功能磁共振(f MRI)扫描,收集两组的一般临床特征,并采用面孔情绪测试评价被试的面孔情绪认知功能;以双侧背外侧前额叶(DLPFC)为种子点比较两组间额顶网络功能连接的差异,并分析与面孔情绪认知功能的相关性。结果:与正常对照组相比,患者组DLPFC与左顶下小叶(t=-3.243,Alphasim校正P<0.05)、左额下回(t=-3.151,Alphasim校正P<0.05)、左额中回(t=-3.151,Alphasim校正P<0.05)、双侧尾状核(t=-4.325,Alphasim校正P<0.05)、左颞中回(t=-3.120,Alphasim校正P<0.05)的功能连接减低;与双侧扣带回中部(t=2.731,Alphasim校正P<0.05)、右中央前回(t=3.991,Alphasim校正P<0.05)、右岛叶(t=3.991,Alphasim校正P<0.05)功能连接增强。患者组额-顶通路的功能连接与面孔情绪认知障碍呈正相关(r=0.501,P<0.05)。结论:首发精神分裂症患者额顶网络的功能连接存在异常,其中DLPFC-顶下小叶通路的功能连接降低可能影响患者面孔情绪识别能力。 展开更多
关键词 精神分裂症 静息态功能磁共振 额顶网络 面孔情绪认知
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Self-diagnosis method for faulty modules on wireless sensor node
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作者 赵军 陈祥光 +1 位作者 李智敏 吴磊 《Journal of Beijing Institute of Technology》 EI CAS 2013年第2期271-277,共7页
In order to diagnose the working status of each module on sensor node and make sure the wireless sensor networks (WSN) work properly, the components of sensor node and their working characteristics are studied. An o... In order to diagnose the working status of each module on sensor node and make sure the wireless sensor networks (WSN) work properly, the components of sensor node and their working characteristics are studied. An on-line fault self-diagnosis method for sensor node is proposed. First, a flexible fault sensing circuit is designed as a state detection module on sensor node. Second, a self- diagnosis algorithm is proposed based on the hardware design and the failure analysis on sensor node. Finally, in order to ensure the WSN reliability, the voltage changes of each module working statuses can be observed using the state detection module and the faulty module will be found out timely. The experimental results show that this self-diagnosis method is suitable to sensor nodes in WSN. 展开更多
关键词 voltage detection self-diagnose algorithm state detection module wireless sensor net- work
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Image mathematical morphology and image restoration application in detecting underground bin level
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作者 孙继平 吴冰 《Journal of Coal Science & Engineering(China)》 2004年第2期105-110,共6页
By using image recognition technology, the underground bin level can be detdcted. The bin image is noised by vibration, atomy, backgroun and so on. The image restoration and image mathematical morphology were used bas... By using image recognition technology, the underground bin level can be detdcted. The bin image is noised by vibration, atomy, backgroun and so on. The image restoration and image mathematical morphology were used based on neural network. A modified Hopfield network was presented for image restoration. The greed algorithm with n-simultaneous updates and apartially asynchronous algorithm were combined, im- proving convergence and avoiding synchronization penalties. Mathematical morphology was widely applicated in digital image processing. The basic idea of mathematical mor- phology is to use construction element measure image morphology for solving under- stand problem. Presented advanced Cellular neural network that forms MMCNN equa- tion to be suit for mathematical morphology filter. It gave the theory of MMCNN dynamic extent and stable state. It was evidenced that arrived mathematical morphology filter through steady of dynamic precess in definite condition. The results of implementation were applied in detecting undergroug bin level. 展开更多
关键词 restoration mathematical morphology pre-processing image neural net- work filter dilation/erosion
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