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COMPRESSED SPEECH SIGNAL SENSING BASED ON THE STRUCTURED BLOCK SPARSITY WITH PARTIAL KNOWLEDGE OF SUPPORT 被引量:1
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作者 JiYunyun YangZhen xuqian 《Journal of Electronics(China)》 2012年第1期62-71,共10页
Structural and statistical characteristics of signals can improve the performance of Compressed Sensing (CS). Two kinds of features of Discrete Cosine Transform (DCT) coefficients of voiced speech signals are discusse... Structural and statistical characteristics of signals can improve the performance of Compressed Sensing (CS). Two kinds of features of Discrete Cosine Transform (DCT) coefficients of voiced speech signals are discussed in this paper. The first one is the block sparsity of DCT coefficients of voiced speech formulated from two different aspects which are the distribution of the DCT coefficients of voiced speech and the comparison of reconstruction performance between the mixed program and Basis Pursuit (BP). The block sparsity of DCT coefficients of voiced speech means that some algorithms of block-sparse CS can be used to improve the recovery performance of speech signals. It is proved by the simulation results of the mixed program which is an improved version of the mixed program. The second one is the well known large DCT coefficients of voiced speech focus on low frequency. In line with this feature, a special Gaussian and Partial Identity Joint (GPIJ) matrix is constructed as the sensing matrix for voiced speech signals. Simulation results show that the GPIJ matrix outperforms the classical Gaussian matrix for speech signals of male and female adults. 展开更多
关键词 Compressed Sensing (CS) Speech signals Sensing matrix Block sparsity
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大气湍流间歇性对玉米花粉风扩散的潜在影响 被引量:3
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作者 徐倩 陈渝 +1 位作者 袁荣 傅林涛 《成都大学学报(自然科学版)》 2018年第1期1-7,共7页
现有研究成果已充分认识到大气湍流间歇性损耗将对大气边界层中颗粒物质的输送过程产生重要影响.然而,目前关于耗散间歇性对玉米花粉传播潜在影响的相关研究较为欠缺.基于拉格朗日随机模型,以耗散速率的时间变化为关键参量,定量地评估... 现有研究成果已充分认识到大气湍流间歇性损耗将对大气边界层中颗粒物质的输送过程产生重要影响.然而,目前关于耗散间歇性对玉米花粉传播潜在影响的相关研究较为欠缺.基于拉格朗日随机模型,以耗散速率的时间变化为关键参量,定量地评估了大气湍流间歇性对玉米花粉传播的影响.数值分析结果表明,大气湍流间歇性能够增加花粉在花粉源附近及较远位置的分布几率;与稳定的大气条件相比,湍流间歇性对玉米花粉的传播,特别是对远距离传播能够产生更大的影响,且随着无量纲耗散率分布均方差的增加,长距离传播的统计物理量响应也将存在差异.研究表明,在复杂自然条件下,用一个特定的特征值或固定函数来描述玉米花粉的传播分布可能已不再适用,而需要找到一种更合理的描述方法. 展开更多
关键词 风湍流 间歇性 拉格朗日随机模型 远距离传播
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Quantitative Analysis of Groundwater Flow near a Partially Penetrating River under Riverside Pumping
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作者 WANGBingchen ZHENGXilai +2 位作者 QIANHui LINGuoqing xuqian 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2004年第3期820-824,共5页
According to practical geological and hydrogeological conditions of riverside water-supply well fields in northwestern China, an ideal hydrogeological model has been generalized and a three-dimensional mathematical mo... According to practical geological and hydrogeological conditions of riverside water-supply well fields in northwestern China, an ideal hydrogeological model has been generalized and a three-dimensional mathematical model has been set up. A finite difference method was applied to simulating groundwater flow near a partially penetrating river under riverside pumping, and to analyzing the effects of river width, partial penetration and permeability of riverbed sediments on groundwater recharges. Results show that riverside pumping may cause groundwater to flow beneath the partially penetrating river, and that river width, penetration and riverbed permeability obviously influence flows from the partially penetrating river and constant-head boundaries. However, the pumping output is mainly from the partially penetrating river. 展开更多
关键词 groundwater flow partially penetrating river riverside pumping numerical analysis
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