This paper aimed at incorporating the precautionary principles into the planning and development of GSM （global system for mobile communications） masts within the built-up areas of Jimeta. Using GIS （geographic inf...This paper aimed at incorporating the precautionary principles into the planning and development of GSM （global system for mobile communications） masts within the built-up areas of Jimeta. Using GIS （geographic information system） analysis technique, the zone of precautionary principle was defined to 500 meters radius as the zone within which precautionary measures are exercised. The criteria for siting GSM base station are also equally identified. For instance, the presence of certain elements within the precautionary zone like schools, hospitals, residential density and overlap of RF （radio frequency） occurrences, may disqualify any mast location. Analysis of the land use within precautionary zone has shown various proportions of exposure to RF, whereas, only 3.39% of the masts are suitably located and 94.92% are not and therefore should be relocated. The study recommend measures for addressing physical development within precautionary areas, including land conversion and mast sharing to reduce potential harmful effects of RF emanating from GSM base stations.展开更多
The study presents a novel source location method based on EEMD （ensemble empirical mode decomposition） and optimized FastICA （independent component analysis） for determining the position of the AE （acoustic emis...The study presents a novel source location method based on EEMD （ensemble empirical mode decomposition） and optimized FastICA （independent component analysis） for determining the position of the AE （acoustic emission） sources in the damage structure of crane. Firstly, The AE signals are self-adaptive decomposed into a number of IMFs （intrinsic mode functions） by using EEMD algorithm. Then, the main feature IMFs signals are extracted as the effective AE source signal by optimized Fast-ICA method, the PSD （power spectral density） of each IMF and the real IMFs are obtained. According to the principle of spectrum similarity, time delay is computed at the different channels in combination with the Cross Correlation time delay estimation principle. Thirdly, a novel source location algorithm based on EEMD-FastICA is proposed and the results of AE source location are obtained. Finally, the three-point bending test for the crane is implemented in order to validate the efficiency of the proposed method. The experimental results indicate that the proposed method has the ability to determinate the position of the AE sources and reduce the interference noises. Moreover, compared with the traditional location algorithm, a considerable improvement is obtained.展开更多
With the increasing scale of distribution networks and the mass access of distributed generation,traditional central-ized fault location methods can no longer meet the performance requirements of speed and high accura...With the increasing scale of distribution networks and the mass access of distributed generation,traditional central-ized fault location methods can no longer meet the performance requirements of speed and high accuracy.There-fore,this paper proposes a fault segment location method based on spiking neural P systems and Bayesian estimation for distribution networks with distributed generation.First,the distribution network system topology is decoupled into single-branch networks.A spiking neural P system with excitatory and inhibitory synapses is then proposed to model the suspected faulty segment,and its matrix reasoning algorithm is executed to obtain a preliminary set of location results.Finally,the Bayesian estimation and contradiction principle are applied to verify and correct the ini-tial results to obtain the final location results.Simulation results based on the IEEE 33-node system validate the feasi-bility and effectiveness of the proposed method.展开更多
文摘This paper aimed at incorporating the precautionary principles into the planning and development of GSM （global system for mobile communications） masts within the built-up areas of Jimeta. Using GIS （geographic information system） analysis technique, the zone of precautionary principle was defined to 500 meters radius as the zone within which precautionary measures are exercised. The criteria for siting GSM base station are also equally identified. For instance, the presence of certain elements within the precautionary zone like schools, hospitals, residential density and overlap of RF （radio frequency） occurrences, may disqualify any mast location. Analysis of the land use within precautionary zone has shown various proportions of exposure to RF, whereas, only 3.39% of the masts are suitably located and 94.92% are not and therefore should be relocated. The study recommend measures for addressing physical development within precautionary areas, including land conversion and mast sharing to reduce potential harmful effects of RF emanating from GSM base stations.
基金Acknowledgments This work is supported by the National Natural Science Foundation of China （51575101, 51305176）, the funds of High-level talents of JIT （JIT6201623, FHXM201608）.
文摘The study presents a novel source location method based on EEMD （ensemble empirical mode decomposition） and optimized FastICA （independent component analysis） for determining the position of the AE （acoustic emission） sources in the damage structure of crane. Firstly, The AE signals are self-adaptive decomposed into a number of IMFs （intrinsic mode functions） by using EEMD algorithm. Then, the main feature IMFs signals are extracted as the effective AE source signal by optimized Fast-ICA method, the PSD （power spectral density） of each IMF and the real IMFs are obtained. According to the principle of spectrum similarity, time delay is computed at the different channels in combination with the Cross Correlation time delay estimation principle. Thirdly, a novel source location algorithm based on EEMD-FastICA is proposed and the results of AE source location are obtained. Finally, the three-point bending test for the crane is implemented in order to validate the efficiency of the proposed method. The experimental results indicate that the proposed method has the ability to determinate the position of the AE sources and reduce the interference noises. Moreover, compared with the traditional location algorithm, a considerable improvement is obtained.
基金funded by grants from the National Natural Science Foundation of China(61703345)the Chunhui Project Foundation of the Education Department of China(Z201980)the Open Research Subject of Key Laboratory of Fluid and Power Machinery(Xihua University),Ministry of Education(szjj2019-27).
文摘With the increasing scale of distribution networks and the mass access of distributed generation,traditional central-ized fault location methods can no longer meet the performance requirements of speed and high accuracy.There-fore,this paper proposes a fault segment location method based on spiking neural P systems and Bayesian estimation for distribution networks with distributed generation.First,the distribution network system topology is decoupled into single-branch networks.A spiking neural P system with excitatory and inhibitory synapses is then proposed to model the suspected faulty segment,and its matrix reasoning algorithm is executed to obtain a preliminary set of location results.Finally,the Bayesian estimation and contradiction principle are applied to verify and correct the ini-tial results to obtain the final location results.Simulation results based on the IEEE 33-node system validate the feasi-bility and effectiveness of the proposed method.
