In a large-scale wireless sensor network(WSN),densely distributed sensor nodes process a large amount of data.The aggregation of data in a network can consume a great amount of energy.To balance and reduce the energy ...In a large-scale wireless sensor network(WSN),densely distributed sensor nodes process a large amount of data.The aggregation of data in a network can consume a great amount of energy.To balance and reduce the energy consumption of nodes in a WSN and extend the network life,this paper proposes a nonuniform clustering routing algorithm based on the improved K-means algorithm.The algorithm uses a clustering method to form and optimize clusters,and it selects appropriate cluster heads to balance network energy consumption and extend the life cycle of the WSN.To ensure that the cluster head(CH)selection in the network is fair and that the location of the selected CH is not concentrated within a certain range,we chose the appropriate CH competition radius.Simulation results show that,compared with LEACH,LEACH-C,and the DEEC clustering algorithm,this algorithm can effectively balance the energy consumption of the CH and extend the network life.展开更多
The power supplies of wireless sensor networks (WSNs) are not replaceable orrechargeable forsensors. For reducing the communication protocols’ impact onthe sensor network’s energy dissipation,various protocols or me...The power supplies of wireless sensor networks (WSNs) are not replaceable orrechargeable forsensors. For reducing the communication protocols’ impact onthe sensor network’s energy dissipation,various protocols or mechanisms havebeen proposed. Therefore, this article proposesa stable random number-basedLEACH protocol to stabilize the random number generation toimprove the CHselection efficiency. The wireless sensor network’s average node energy (ANE)ismultiplied by the random number that relies on the nodes’ energy. A nodegrade algorithm(NGA) based relay selection is introduced for inter andintracluster communication for energy efficiencyenhancement. The proposed NGA calculates the grade of a node using residual energy,distance from CHs,and its traffic parameters. Based on the simulation results, the proposedSRN-LEACH protocol shows superior performance as compared to existing protocolsincludingreduced energy dissipation, improved communication quality, andNLT. The proposed methodattains a minimum average delay of 0.136ms, 0.95% PDR, 148kbps TP rate, and 98% NLT.展开更多
In this paper, a novel method that integrates the improved empirical mode decomposition （EMD） and signal energy algorithm is proposed to estimate the dominant oscillation parameters and corresponding mode shape. Fir...In this paper, a novel method that integrates the improved empirical mode decomposition （EMD） and signal energy algorithm is proposed to estimate the dominant oscillation parameters and corresponding mode shape. Firstly, the EMD with symmetrical extrema extension （SEE） is utilized to decompose the measured data from wide area measurement system （WAMS） into a finite set of intrinsic mode functions （1MFs）. Then, the signal energy algorithm is used to calculate the approximate oscillation parameters of the IMFs. The nodes involved the dominant oscillation mode are classified based on the calculated frequency and reasonable threshold. Furthermore, for the dominant oscillation mode, the IMF with maximum mean amplitude is defined as the reference. Next, the relative phases （RPs） between the reference IMF and other 1MFs are calculated in order to identify the negative and positive oscillation groups. According to the values of RPs, the coherent group and corresponding node contribution factor （NCF） can be identified, and the dominant approximate mode shape （AMS） can also be determined. The efficiency of the proposed approach is tested by applying it to synthetic signal and measured data from the simulation model.展开更多
基金This research was funded by the Science and Technology Support Plan Project of Hebei Province(grant numbers 17210803D and 19273703D)the Science and Technology Spark Project of the Hebei Seismological Bureau(grant number DZ20180402056)+1 种基金the Education Department of Hebei Province(grant number QN2018095)the Polytechnic College of Hebei University of Science and Technology.
文摘In a large-scale wireless sensor network(WSN),densely distributed sensor nodes process a large amount of data.The aggregation of data in a network can consume a great amount of energy.To balance and reduce the energy consumption of nodes in a WSN and extend the network life,this paper proposes a nonuniform clustering routing algorithm based on the improved K-means algorithm.The algorithm uses a clustering method to form and optimize clusters,and it selects appropriate cluster heads to balance network energy consumption and extend the life cycle of the WSN.To ensure that the cluster head(CH)selection in the network is fair and that the location of the selected CH is not concentrated within a certain range,we chose the appropriate CH competition radius.Simulation results show that,compared with LEACH,LEACH-C,and the DEEC clustering algorithm,this algorithm can effectively balance the energy consumption of the CH and extend the network life.
文摘The power supplies of wireless sensor networks (WSNs) are not replaceable orrechargeable forsensors. For reducing the communication protocols’ impact onthe sensor network’s energy dissipation,various protocols or mechanisms havebeen proposed. Therefore, this article proposesa stable random number-basedLEACH protocol to stabilize the random number generation toimprove the CHselection efficiency. The wireless sensor network’s average node energy (ANE)ismultiplied by the random number that relies on the nodes’ energy. A nodegrade algorithm(NGA) based relay selection is introduced for inter andintracluster communication for energy efficiencyenhancement. The proposed NGA calculates the grade of a node using residual energy,distance from CHs,and its traffic parameters. Based on the simulation results, the proposedSRN-LEACH protocol shows superior performance as compared to existing protocolsincludingreduced energy dissipation, improved communication quality, andNLT. The proposed methodattains a minimum average delay of 0.136ms, 0.95% PDR, 148kbps TP rate, and 98% NLT.
文摘In this paper, a novel method that integrates the improved empirical mode decomposition （EMD） and signal energy algorithm is proposed to estimate the dominant oscillation parameters and corresponding mode shape. Firstly, the EMD with symmetrical extrema extension （SEE） is utilized to decompose the measured data from wide area measurement system （WAMS） into a finite set of intrinsic mode functions （1MFs）. Then, the signal energy algorithm is used to calculate the approximate oscillation parameters of the IMFs. The nodes involved the dominant oscillation mode are classified based on the calculated frequency and reasonable threshold. Furthermore, for the dominant oscillation mode, the IMF with maximum mean amplitude is defined as the reference. Next, the relative phases （RPs） between the reference IMF and other 1MFs are calculated in order to identify the negative and positive oscillation groups. According to the values of RPs, the coherent group and corresponding node contribution factor （NCF） can be identified, and the dominant approximate mode shape （AMS） can also be determined. The efficiency of the proposed approach is tested by applying it to synthetic signal and measured data from the simulation model.
