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雷达通信干扰一体化OFDM共享波形优化方法 被引量:3
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作者 朱晟坤 杨瑞娟 +1 位作者 左家骏 李东瑾 《兵器装备工程学报》 CAS 北大核心 2020年第11期218-223,共6页
为了在正交频分复用(OFDM)雷达通信一体化共享信号基础上实现雷达通信干扰功能一体化,提出了一种共享波形优化方法。首先分别建立了目标脉冲响应与接收信号的条件互信息、频率选择性信道数据率、干扰熵值等雷达、通信、干扰功能的目标函... 为了在正交频分复用(OFDM)雷达通信一体化共享信号基础上实现雷达通信干扰功能一体化,提出了一种共享波形优化方法。首先分别建立了目标脉冲响应与接收信号的条件互信息、频率选择性信道数据率、干扰熵值等雷达、通信、干扰功能的目标函数,然后建立了权重配置的一体化目标函数,给出了基于遗传算法的OFDM子载波功率优化方法;结果表明:在损失少部分雷达和通信性能信息的前提下,能够使OFDM信号获得较强的干扰能力,使得雷达通信干扰一体化性能最优,并且能够根据雷达、通信、干扰性能的需求,通过优化权重配置,使一体化系统总体性能保持最优,可为雷达通信干扰一体化应用提供理论参考。 展开更多
关键词 正交频分复用 条件互信息 数据信息率 干扰熵值 功率约束 遗传算法
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Topology-Based Data Dissemination Approaches for Large Scale Data Centric Networking Architecture
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作者 陈佳 张宏科 周华春 《China Communications》 SCIE CSCD 2013年第9期80-96,共17页
Massive information flows are gen- erated from interactive processing and visua- lizations. To efficiently support information transmission over the Interact, information cen- tric architecture has been recently propo... Massive information flows are gen- erated from interactive processing and visua- lizations. To efficiently support information transmission over the Interact, information cen- tric architecture has been recently proposed. In this paper, we consider an information centric architecture, called the data centric networking architecture to provide communication servi- ces to big data, where a service identifier is used to name the data objects. We propose dif- ferent approaches for the dissemination of data objects in a large-scale data centric network. In particular, we propose various approaches to link the data dissemination approach with the topology of the Internet. Further, we eva- luate the proposed approaches with respect to data delivery efficiency, round-trip time imp- rovement, and deployment cost. Based on the results obtained from this study, it can be sh- own that by disseminating data objects to small ISPs, the data delivery efficiency can be significantly improved within an acceptable deployment cost. 展开更多
关键词 data centric networking data dis-semination topology-based
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Coordinated multi-point transmission technique in TDD cellular mobile system 被引量:1
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作者 Rakesh Tamrakar 《Engineering Sciences》 EI 2011年第1期35-40,共6页
Coordinated multi-point transmission/reception, CoMP, technique converts the interference signal into the useful information by controlling the interfering signals among adjacent cells. Theoretically, it is a breakthr... Coordinated multi-point transmission/reception, CoMP, technique converts the interference signal into the useful information by controlling the interfering signals among adjacent cells. Theoretically, it is a breakthrough from the traditional interference limited non-cooperative single point transmission system, improving link reliability and enhancing the data rate. CoMP is regarded as one of the most essential and effective techniques in eliminating the inter-cell interference, boosting cell edge throughput and overall system throughput. CoMP technique has obvious advantages in TDD(time division duplexing) cellular mobile system; the necessary channel state information for CoMP can be easily obtained through channel reciprocity property in TDD system. CoMP scheme in TDD system and likely problems are analyzed in this paper, and it is shown by system simulations that the significant gain can be achieved. 展开更多
关键词 multi antenna technique COMP TDD system channel reciprocity
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Research on the Applications of Probability Model and Matrix Transformation in Data Analysis and Management under the Environment of Information Time
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作者 Ying Cao 《International Journal of Technology Management》 2015年第7期152-154,共3页
In this paper, we research the probability theory and matrix transformation based technique to manage the data for processing and analysis. Clustering analysis research has a long history, over the decades, the import... In this paper, we research the probability theory and matrix transformation based technique to manage the data for processing and analysis. Clustering analysis research has a long history, over the decades, the importance and the cross characteristics with other research direction to get the affirmation of the people. The probability theory and linear algebra act as the powerful tool for analyzing and mining data. The experimental result illustrates the effectiveness. In the near future, we plan to conduct more theoretical analysis on the topic. 展开更多
关键词 Probability Model Matrix Transformation Data Analysis and Management.
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Two-way Markov random walk transductive learning algorithm
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作者 李宏 卢小燕 +1 位作者 刘玮文 Clement K.Kirui 《Journal of Central South University》 SCIE EI CAS 2014年第3期970-977,共8页
Researchers face many class prediction challenges stemming from a small size of training data vis-a-vis a large number of unlabeled samples to be predicted. Transductive learning is proposed to utilize information abo... Researchers face many class prediction challenges stemming from a small size of training data vis-a-vis a large number of unlabeled samples to be predicted. Transductive learning is proposed to utilize information about unlabeled data to estimate labels of the unlabeled data for this condition. This work presents a new transductive learning method called two-way Markov random walk(TMRW) algorithm. The algorithm uses information about labeled and unlabeled data to predict the labels of the unlabeled data by taking random walks between the labeled and unlabeled data where data points are viewed as nodes of a graph. The labeled points correlate to unlabeled points and vice versa according to a transition probability matrix. We can get the predicted labels of unlabeled samples by combining the results of the two-way walks. Finally, ensemble learning is combined with transductive learning, and Adboost.MH is taken as the study framework to improve the performance of TMRW, which is the basic learner. Experiments show that this algorithm can predict labels of unlabeled data well. 展开更多
关键词 CLASSIFICATION transductive learning two-way Markov random walk (TMRW) Adboost.MH
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Fatigue reliability assessment for bridge welded details using long-term monitoring data 被引量:24
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作者 DENG Yang DING YouLiang +1 位作者 LI AiQun ZHOU GuangDong 《Science China(Technological Sciences)》 SCIE EI CAS 2011年第12期3371-3381,共11页
A reliability assessment method of fatigue life based on the long-term monitoring data is developed for welded details in steel box girder,and the application research is presented with examples of welded rib-to-deck ... A reliability assessment method of fatigue life based on the long-term monitoring data is developed for welded details in steel box girder,and the application research is presented with examples of welded rib-to-deck details in Runyang Bridges. Firstly the fatigue damage limit-state function is established based on S-N curves and Miner's rule,and the probability distribution characteristics of the coefficients in the function are discussed in detail. The uncertainties in fatigue loading effects are mainly studied based on long-term monitoring data. In the traditional studies,only the uncertainty of equivalent stress range is considered in fatigue reliability assessment. However,stress cycle number is also treated as a random variable in this paper because we know traffic flow every day differs in a thousand ways. Then the optimization method is employed to calculate the fatigue reliability. After studying the changing law of the reliability indices with time and the effect of the randomness of stress cycle number on reliability,the effect of the traffic growth on the reliability is studied. This study shows that the uncertainty in the fatigue life of the welded details can be well studied based on structural health monitoring,so it is necessary to carry out long-term strain monitoring of the welded details for accurate fatigue reliability assessment during the whole service period. 展开更多
关键词 steel box girder fatigue loading effects equivalent stress range stress cycle number fatigue reliability traffic growth
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