In this paper, the energy-efficient power control problem in cognitive radio （CR） networks is studied not only to provide energy-efficient transmission, but also to guarantee the normal operation of primary users （...In this paper, the energy-efficient power control problem in cognitive radio （CR） networks is studied not only to provide energy-efficient transmission, but also to guarantee the normal operation of primary users （PUs）. Moreover, the static energy-efficient power control （SEPC） algorithm is proposed in static scenario to maximize the capacity of secondary users （SUs） and to reduce the power consumption according to the interference from PU to SU. Furthermore, based on the analysis of PU＇s dynamic feature with Markov chain and SEPC algorithm,the dynamic energy-efficient power control （DEPC） algorithm is proposed taking into account the probability of detection and false alarm caused by sensing errors. Extensive simulation results show that the performance of the proposed algorithms is significantly improved compared with the existing algorithm.展开更多
In the relationship between humans and the environment,all human activities depend on the geographical environment,which serves as the spatial place and material foundation for human life.This study provides a perspec...In the relationship between humans and the environment,all human activities depend on the geographical environment,which serves as the spatial place and material foundation for human life.This study provides a perspective on the human-environment relationship,using a case study of the Dashanbao Mountainous Outdoor Tourism Planning Area in Zhaotong,Yunnan.This study employed methods such as literature review,on-site investigation,and GIS spatial analysis to analyze the functional characteristics of the regional subject,spatial structuring,and spatiotemporally variable ordered processes of Dashanbao as a tourism destination from the perspective of human-environment relationships.The results indicate that under the guidance of the human-environment relationship system philosophy,the construction path of the“ecological space,production space,and living space”includes three main aspects:(1)The formation of five major project blocks and five functional zones to meet the diverse needs of different groups;(2)The establishment of a"multi-core module"structure optimizing the spatial layout of the tourism destination;and(3)With the changes in space and time,the convergence of elements in each block can form a composite mountainous outdoor tourism space with the characteristics of“ecology,life,and production”.The results of this study provide a scientific basis for promoting the sustainable development of tourism regional systems with mountainous characteristics.展开更多
基金the National Natural Science Foundation of China，Beijing Municipal Natural Science Foundation，the Key Project of Ministry of Industry and Information Technology，the National Youth Science Foundation
文摘In this paper, the energy-efficient power control problem in cognitive radio （CR） networks is studied not only to provide energy-efficient transmission, but also to guarantee the normal operation of primary users （PUs）. Moreover, the static energy-efficient power control （SEPC） algorithm is proposed in static scenario to maximize the capacity of secondary users （SUs） and to reduce the power consumption according to the interference from PU to SU. Furthermore, based on the analysis of PU＇s dynamic feature with Markov chain and SEPC algorithm,the dynamic energy-efficient power control （DEPC） algorithm is proposed taking into account the probability of detection and false alarm caused by sensing errors. Extensive simulation results show that the performance of the proposed algorithms is significantly improved compared with the existing algorithm.
基金The Sichuan Provincial Key Research Base of Philosophy and Social Sciences(WRF202401)The Key Research Base of Sichuan Provincial Department of Education Humanities and Social Science(XXTYCY2023C17)The Sichuan Provincial Key Research Base for Humanities and Social Sciences in Higher Education(HWYD2024B10)。
文摘In the relationship between humans and the environment,all human activities depend on the geographical environment,which serves as the spatial place and material foundation for human life.This study provides a perspective on the human-environment relationship,using a case study of the Dashanbao Mountainous Outdoor Tourism Planning Area in Zhaotong,Yunnan.This study employed methods such as literature review,on-site investigation,and GIS spatial analysis to analyze the functional characteristics of the regional subject,spatial structuring,and spatiotemporally variable ordered processes of Dashanbao as a tourism destination from the perspective of human-environment relationships.The results indicate that under the guidance of the human-environment relationship system philosophy,the construction path of the“ecological space,production space,and living space”includes three main aspects:(1)The formation of five major project blocks and five functional zones to meet the diverse needs of different groups;(2)The establishment of a"multi-core module"structure optimizing the spatial layout of the tourism destination;and(3)With the changes in space and time,the convergence of elements in each block can form a composite mountainous outdoor tourism space with the characteristics of“ecology,life,and production”.The results of this study provide a scientific basis for promoting the sustainable development of tourism regional systems with mountainous characteristics.
