广泛工作在ISM(Industrial,Scientific and Medical)频段的无线传感器网络面临严重的频谱稀缺问题。在无线通信中,动态频谱分配被认为是提高频谱效能的重要途径。针对典型集中式管理的认知无线传感器网络设计了基于图着色结合负载强度...广泛工作在ISM(Industrial,Scientific and Medical)频段的无线传感器网络面临严重的频谱稀缺问题。在无线通信中,动态频谱分配被认为是提高频谱效能的重要途径。针对典型集中式管理的认知无线传感器网络设计了基于图着色结合负载强度的高效频谱分配算法。首先在协议干扰模型下确保频谱资源在空间上充分利用,随后综合考虑节点负载强度与公平性建立优化模型并按照乘子法加拟牛顿法框架求解最优值。仿真实验表明算法与固定频谱分配方式和传统自适应频谱分配算法相比,在系统吞吐量和节点缓冲区队列长度两个关键性能指标上具有显著优势。展开更多
This thesis studies the concept and research background of filzziness and fuzzy theory, then committing further enumeration and analysis of the application of fuzzy theory in the fields of linguistics and literature. ...This thesis studies the concept and research background of filzziness and fuzzy theory, then committing further enumeration and analysis of the application of fuzzy theory in the fields of linguistics and literature. On this basis, the effectiveness and rationalization of the fuzzy theory＇s application in the English literature teaching were confirmed from many aspects. Among them, it is mainly investigated and analyzed from the objective factors and subjective factors. Subjective aspects mainly contain students＇ different cognitive ability, and the diversity existed in teachers＇ teaching and guiding methods. Objective aspects mainly include that the literature language and literature thoughts itself have the unique ambiguity. Finally, in summing up the investigation results the author put forward the essence of English literature teaching activity and put forward the methods to improve English literature teaching.展开更多
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
文摘广泛工作在ISM(Industrial,Scientific and Medical)频段的无线传感器网络面临严重的频谱稀缺问题。在无线通信中,动态频谱分配被认为是提高频谱效能的重要途径。针对典型集中式管理的认知无线传感器网络设计了基于图着色结合负载强度的高效频谱分配算法。首先在协议干扰模型下确保频谱资源在空间上充分利用,随后综合考虑节点负载强度与公平性建立优化模型并按照乘子法加拟牛顿法框架求解最优值。仿真实验表明算法与固定频谱分配方式和传统自适应频谱分配算法相比,在系统吞吐量和节点缓冲区队列长度两个关键性能指标上具有显著优势。
文摘This thesis studies the concept and research background of filzziness and fuzzy theory, then committing further enumeration and analysis of the application of fuzzy theory in the fields of linguistics and literature. On this basis, the effectiveness and rationalization of the fuzzy theory＇s application in the English literature teaching were confirmed from many aspects. Among them, it is mainly investigated and analyzed from the objective factors and subjective factors. Subjective aspects mainly contain students＇ different cognitive ability, and the diversity existed in teachers＇ teaching and guiding methods. Objective aspects mainly include that the literature language and literature thoughts itself have the unique ambiguity. Finally, in summing up the investigation results the author put forward the essence of English literature teaching activity and put forward the methods to improve English literature teaching.
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.
