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Z干扰信道；非正则信号；和速率；帕累托边界；协方差；伪协方差 1

特征分析；干扰噪声协方差矩阵重建；最大信干噪比准则；阻塞矩阵；广义旁瓣消除器；到达方向失配 1

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Analysis of nonlinear channel friction inverse problem

CHENG Weiping, LIU Guohua

《结构与土木工程前沿（英文）》 2007年 第1卷 第2期   页码 205-210 doi: 10.1007/s11709-007-0024-0

摘要： Based on the Backus-Gilbert inverse theory, the singular value decomposition (SVD) for general inverse matrices and the optimization algorithm are used to solve the channel friction inverse problem. The resolution and covariance friction inverse model in matrix form is developed to examine the reliability of solutions. Theoretical analyses demonstrate that the convergence rate of the general Newton optimization algorithm is in the second-order. The Wiggins method is also incorporated into the algorithm. Using the method, noise can be suppressed effectively, and the results are close to accurate solutions with proper control parameters. Also, the numerical stability can be improved.

关键词： singular     SVD     second-order     covariance     Theoretical    

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Z干扰信道下非正则信号的最佳设计策略 Article

Dan LI, Shan WANG, Fang-lin GU

《信息与电子工程前沿（英文）》 2017年 第18卷 第11期   页码 1900-1912 doi: 10.1631/FITEE.1700030

摘要： 本文提出一种用于在干扰被视为加性高斯噪声的假设下在Z干扰信道（z-interference channel, Z-IC）上实现非正则高斯信号（IGS）的Pareto边界（可实现速率区域的边界）。具体来说，文章表明了帕累托边界可由某个用户的传输速率的两个区域表征，由传输信号的方差与伪协方差的两个变化路径决定。为每个用户发送的非正则信号的最优协方差和伪协方差设计推导出简明闭合的表达式。为此，我们通过仿真试验有力证明了所提出的最优信号设计策略的有效性，同时直观地展现出IGS较正则高斯信号（proper Gaussian signaling, PGS）的优越性。此外，我们提出的最优信号设计策略提供了实现所需速率区域的简单方法。利用该方法，我们得到了一个闭合形式的解决方案，用于快速确定最大和速率的信号设计方案。最后，我们深入讨论了帕累托边界的特征，定性分析了信道系数以及两个用户发送的信号的协方差和伪协方差与其的关系。

关键词： Z干扰信道；非正则信号；和速率；帕累托边界；协方差；伪协方差    

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Perception of people for the risk of Tianwan nuclear power plant

Lei HUANG, Jun BI, Bing ZHANG, Fengying LI, Changsheng QU,

《环境科学与工程前沿（英文）》 2010年 第4卷 第1期   页码 73-81 doi: 10.1007/s11783-009-0151-z

摘要： A questionnaire survey of residents’ risk perceptions related to Taiwan nuclear power plant in China was carried out to explore the determining factors that affect individual risk perception. This study proposed to pursue a more comprehensive understanding of factors that affected individual risk perception to nuclear power plants. Covariance structure analysis was conducted using risk perceptions of nuclear power as dependent variable and including interest and knowledge levels of nuclear power, acceptability, benefit perception, trust in nuclear power operation, and trust in government as independent variables. The use of the hypothesis of Elaboration likelihood model (ELM) was also proposed. The results showed that persons with higher levels of interest and knowledge of nuclear power had their own perceptions of risk closely associated with acceptability and potential benefits of nuclear power. In contrast, persons with no interest in and knowledge of nuclear power would have risk perceptions related to their trust in nuclear operation and the government, which partially supported the ELM hypothesis. All these results indicated that the government in China plays an important role in rational risk perceptions, and well-designed communication of risks will help the public to be involved in risk management and improve people’s rational acceptance of risk.

关键词： nuclear power     risk perception     public involvement     covariance structure analysis     China    

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Comparison of evapotranspiration and energy partitioning related to main biotic and abiotic controllers in vineyards using different irrigation methods

Lei GAO, Peng ZHAO, Shaozhong KANG, Sien LI, Ling TONG, Risheng DING, Hongna LU

《农业科学与工程前沿（英文）》 2020年 第7卷 第4期   页码 490-504 doi: 10.15302/J-FASE-2019310

摘要：

Knowledge of evapotranspiration (ET) and energy partitioning is useful for optimizing water management, especially in areas where water is scarce. A study was undertaken in a furrow-irrigated vineyard (2015) and a drip-irrigated vineyard (2017) in an arid region of north-west China to compare vineyard ET and energy partitioning and their responses to soil water content (SWC) and leaf area index (LAI). ET and soil evaporation (E) and transpiration (T) were determined using eddy covariance, microlysimeters, and sap flow. Seasonal average E/ET, T/ET, crop coefficient (Kc), evaporation coefficient (Ke), and basal crop coefficient (Kcb) were 0.50, 0.50, 0.67, 0.35, and 0.29, respectively, in the furrow-irrigated vineyard and 0.42, 0.58, 0.57, 0.29, and 0.43 in the drip-irrigated vineyard. The seasonal average partitioning of net radiation (Rn) into the latent heat flux (LE), sensible heat flux (H) and soil heat flux (G) (LE/Rn, H/Rn, and G/Rn), evaporative fraction (EF) and Bowen ratio (β) were 0.57, 0.26, 0.17, 0.69 and 0.63, respectively, in the furrow-irrigated vineyard and 0.46, 0.36, 0.17, 0.57 and 0.97 in the drip-irrigated vineyard. The LE/Rn, H/Rn, EF, and β were linearly correlated with LAI. The E, Kc, Ke, E/ET, LE/Rn, LEs/Rn (ratio of LE by soil E to Rn), H/Rn, EF and β were closely correlated with topsoil SWC (10 cm depth). Responses of ET and energy partitioning to the LAI and SWC differed under the two irrigation methods. Drip irrigation reduced seasonal average E/ET and increased average T/ET. From the perspective of energy partitioning, seasonal average H/Rn increased whereas LE/Rn, especially LEs/Rn, decreased. Compared with furrow irrigation, drip irrigation decreased the proportion of unproductive water consumption thereby contributing to enhanced water use efficiency and accumulation of dry matter.

关键词： crop coefficient     eddy covariance     microlysimeter     sap flow     soil evaporation     transpiration    

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基于特征分析和最大信干噪比波束形成器的鲁棒广义旁瓣消除器 Research Articles

Quan-dong WANG, Liang-hao GUO, Wei-yu ZHANG, Sui-ling REN, Chao YAN

《信息与电子工程前沿（英文）》 2019年 第20卷 第7期   页码 975-987 doi: 10.1631/FITEE.1700367

摘要： 提出一种鲁棒的广义旁瓣消除器抵抗到达方向失配的影响。为估计干扰加噪声的统计特性，传统信号提取方法常需收集大量仅存在干扰噪声的信号片段。为避免该收集过程，我们使用特征分析方法重新设计阻塞矩阵结构，从接收样本中重建干扰噪声的协方差矩阵。另外，基于秩-1矩阵假设，改进特征分析重建方法，以实现更高重建精度。将该重建方法与最大信干噪声比波束形成器结合，获得阻塞矩阵，最大限度减少信号泄漏的影响，并最大化干扰噪声功率，以进一步在最终输出中抑制噪声和干扰成分。数值结果表明，在存在到达方向失配和快照数有限的情况下，上述两种方法在输出波形信干噪比和与期望信号的相关系数方面有显著改进。与所提第一种方法相比，改进后的方法可进一步减少信号失真。

关键词： 特征分析；干扰噪声协方差矩阵重建；最大信干噪比准则；阻塞矩阵；广义旁瓣消除器；到达方向失配    

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标题 作者 时间 类型 操作

Analysis of nonlinear channel friction inverse problem

CHENG Weiping, LIU Guohua

期刊论文

Z干扰信道下非正则信号的最佳设计策略

Dan LI, Shan WANG, Fang-lin GU

期刊论文

Perception of people for the risk of Tianwan nuclear power plant

Lei HUANG, Jun BI, Bing ZHANG, Fengying LI, Changsheng QU,

期刊论文

Comparison of evapotranspiration and energy partitioning related to main biotic and abiotic controllers in vineyards using different irrigation methods

Lei GAO, Peng ZHAO, Shaozhong KANG, Sien LI, Ling TONG, Risheng DING, Hongna LU

期刊论文

基于特征分析和最大信干噪比波束形成器的鲁棒广义旁瓣消除器

Quan-dong WANG, Liang-hao GUO, Wei-yu ZHANG, Sui-ling REN, Chao YAN

期刊论文