A K-tier uplink heterogeneous cellular network is modelled and analysed by accounting for both truncated channel inversion power control and biased user association. Each user has a maximum transmit power constraint a...A K-tier uplink heterogeneous cellular network is modelled and analysed by accounting for both truncated channel inversion power control and biased user association. Each user has a maximum transmit power constraint and transmits data when it has sufficient transmit power to perform channel inversion. With biased user association, each user is associated with a base station(BS) that provides the maximum received power weighted by a bias factor, but not their nearest BS. Stochastic geometry is used to evaluate the performances of the proposed system model in terms of the outage probability and ergodic rate for each tier as functions of the biased and power control parameters. Simulations validate our analytical derivations. Numerical results show that there exists a trade-off introduced by the power cut-off threshold and the maximum user transmit power constraint. When the maximum user transmit power becomes a binding constraint, the overall performance is independent of BS densities. In addition, we have shown that it is beneficial for the outage and rate performances by optimizing different network parameters such as the power cut-off threshold as well as the biased factors.展开更多
Artificial photocatalytic energy conversion is considered as the most potential strategy for solving the increasingly serious energy crisis and environmental pollution problems by directly capturing solar energy.There...Artificial photocatalytic energy conversion is considered as the most potential strategy for solving the increasingly serious energy crisis and environmental pollution problems by directly capturing solar energy.Therefore,high efficiency photocatalyst has drawn significant research attention in recent years.Due to the excellent electronic,optical,structural,and physicochemical performances,silver-based g-C_(3)N_(4)have become promising photocatalysts.This review emphasizes the recent progresses and challenges on g-C_(3)N_(4)decorated with silver for photocatalytic energy conversion.The extensive use of g-C_(3)N_(4)decorated with silver in diverse photocatalytic reactions,including hydrogen evolution,pollutant degradation and carbon dioxide reduction,is also fully introduced.In addition,we propose the perspectives of g-C_(3)N_(4)decorated with silver on photocatalytic applications.We hope that this review will shed some light on the photocatalytic energy conversion of g-C_(3)N_(4)decorated with silver.展开更多
基金supported by the National Natural Science Foundation of China (61401225, 61571234)the National Science Foundation of Jiangsu Province (BK20140894, BK20140883, BK20160899)+4 种基金the Six Talented Eminence Foundation of Jiangsu Province (XYDXXJS-044)the National Science Foundation of the Higher Education Institutions of Jiangsu Province (14KJD510007, 16KJB510035)the Jiangsu Planned Projects for Postdoctoral Research Funds (1501125B)China Postdoctoral Science Foundation funded project (2015M581844)the Introduction of Talent Scientific Research Fund of Nanjing University of Posts Telecommunications project (NY213104, NY214190)
文摘A K-tier uplink heterogeneous cellular network is modelled and analysed by accounting for both truncated channel inversion power control and biased user association. Each user has a maximum transmit power constraint and transmits data when it has sufficient transmit power to perform channel inversion. With biased user association, each user is associated with a base station(BS) that provides the maximum received power weighted by a bias factor, but not their nearest BS. Stochastic geometry is used to evaluate the performances of the proposed system model in terms of the outage probability and ergodic rate for each tier as functions of the biased and power control parameters. Simulations validate our analytical derivations. Numerical results show that there exists a trade-off introduced by the power cut-off threshold and the maximum user transmit power constraint. When the maximum user transmit power becomes a binding constraint, the overall performance is independent of BS densities. In addition, we have shown that it is beneficial for the outage and rate performances by optimizing different network parameters such as the power cut-off threshold as well as the biased factors.
基金financially supported by the Shenzhen Science and Technology Program(No.JCYJ20220531093205013)the National Natural Science Foundation of China(No.52100069).
文摘Artificial photocatalytic energy conversion is considered as the most potential strategy for solving the increasingly serious energy crisis and environmental pollution problems by directly capturing solar energy.Therefore,high efficiency photocatalyst has drawn significant research attention in recent years.Due to the excellent electronic,optical,structural,and physicochemical performances,silver-based g-C_(3)N_(4)have become promising photocatalysts.This review emphasizes the recent progresses and challenges on g-C_(3)N_(4)decorated with silver for photocatalytic energy conversion.The extensive use of g-C_(3)N_(4)decorated with silver in diverse photocatalytic reactions,including hydrogen evolution,pollutant degradation and carbon dioxide reduction,is also fully introduced.In addition,we propose the perspectives of g-C_(3)N_(4)decorated with silver on photocatalytic applications.We hope that this review will shed some light on the photocatalytic energy conversion of g-C_(3)N_(4)decorated with silver.