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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 1

中心飘移 1

分形几何；层状金属屏蔽；涡流效应；磁耦合能量传输 1

大涡模拟 1

建筑 1

涡流场 1

火旋风 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

目标体 1

盲炮检测与识别 1

瞬变电磁法 1

硐室爆破 1

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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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A dynamic procedure based on the scale-similarity hypotheses for large-eddy simulation

ZHOU Bing, CUI Guixiang, CHEN Naixiang

《能源前沿（英文）》 2007年第1卷第4期页码 468-472 doi: 10.1007/s11708-007-0069-z

摘要： Current dynamic procedures in large-eddy simulation treat the two subgrid-scale stresses in the Germano identity with the same subgrid base model. Thus to get the base model coefficient, the coefficient must be assumed to be consta

关键词： large-eddy simulation Germano identity coefficient subgrid-scale

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Numerical modeling of current-induced scour around multi-wall foundation using large-eddy simulation

《结构与土木工程前沿（英文）》 2023年第17卷第4期页码 546-565 doi: 10.1007/s11709-023-0943-4

摘要： Scouring is one of the primary triggers of failure for bridges across rivers or seas. However, research concerning the scour mechanism of multi-wall foundations (MWFs) remains scarce, hindering the further application of MWFs. In this study, for the first time, the scouring effect caused by unidirectional flow around MWFs was examined numerically using FLOW-3D involving a large-eddy simulation. Initially, the applicability of the scouring model and input parameters was validated using a case study based on published measured data. Subsequently, the scouring effects of four MWFs with different wall arrangements and inflow angles, including the flow field analysis and scour pit and depth, were investigated thoroughly. It was found that the maximum scour depth of MWFs with an inflow angle of 0° was smaller than that of those with an inflow angle of 45°, regardless of the wall arrangement. Meanwhile, changing the inflow angle significantly affects the scour characteristics of MWFs arranged in parallel. In practical engineering, MWFs arranged in parallel are preferred considering the need for scouring resistance. However, a comparative analysis should be performed to consider comprehensively whether to adopt the form of a round wall arrangement when the inflow angle is not 0° or the inflow direction is changeable.

关键词： multi-wall foundation current-induced scour bridge foundation large-eddy simulation numerical analysis

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Large eddy simulation of turbulent buffet forces in flow induced vibration

XI Zhide, CHENG Bingde, LI Pengzhou

《能源前沿（英文）》 2008年第2卷第4期页码 524-527 doi: 10.1007/s11708-008-0099-x

摘要： The pressure pulse filter and Smagorinsky sub-grid stress model of the Large Eddy Simulation (LES) are introduced. The fluid field in the annular plenum between the pressure vessel and the core barrel of the1:5 model in the second phase of Qinshan Nuclear Power Plant is simulated, and the distribution of the total pressure in the space and time domains is obtained. The results show that the Power Spectrum Density (PSD) of LES from the calculation and the test are in the same quantity order. Thus, the pressure of LES can be a load to stimulate the barrel vibration.

关键词： Spectrum Density Smagorinsky sub-grid vibration calculation Qinshan Nuclear

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Large eddy simulation of a 660 MW utility boiler under variable load conditions

Haoshu SHEN, Yuxin WU, Minmin ZHOU, Hai ZHANG, Guangxi YUE, Junfu LYU

《能源前沿（英文）》 2021年第15卷第1期页码 124-131 doi: 10.1007/s11708-020-0659-2

摘要： Large eddy simulation (LES) has become a promising tool for pulverized coal combustion with the development of computational fluid dynamics (CFD) technologies in recent years. LES can better capture the unsteady features and turbulent structures of coal jet flame than Reynolds averaged Navier Stokes (RANS). The coal-fired power plants in China are now required to be operated in a wide load range and quickly respond to the electric grid. The boiler performance of variable loads should be evaluated in terms of flow, heat transfer, and combustion processes. In this paper, LES was applied to simulate a 660 MW ultra-supercritical boiler under BMCR (boiler maximum continue rate), 75%THA-100, and 50%THA-100 conditions. The predicted gas velocities agree well with the thermal calculation and the temperature error is less than 130 K. The simulation results show that the operation load has significant effects on the boiler performance. It is also proved that LES can provide guidance for the design and operation of advanced coal-fired boilers.

关键词： large eddy simulation ultra-supercritical boiler operation load

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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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Eddy current measurement of the thickness of top Cu film of the multilayer interconnects in the integrated

Zilian QU,Yonggang MENG,Qian ZHAO

《机械工程前沿（英文）》 2015年第10卷第1期页码 1-6 doi: 10.1007/s11465-015-0325-2

摘要：

This paper proposes a new eddy current method, named equivalent unit method (EUM), for the thickness measurement of the top copper film of multilayer interconnects in the chemical mechanical polishing (CMP) process, which is an important step in the integrated circuit (IC) manufacturing. The influence of the underneath circuit layers on the eddy current is modeled and treated as an equivalent film thickness. By subtracting this equivalent film component, the accuracy of the thickness measurement of the top copper layer with an eddy current sensor is improved and the absolute error is 3 nm for sampler measurement.

关键词： CMP eddy current multilayer wafer Cu interconnects equivalent unit

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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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建筑物内火旋风中心飘移的探讨与研究

陈长坤,姚斌,范维澄

《中国工程科学》 2003年第5卷第10期页码 63-68

摘要：

火旋风是火灾中一种较为特殊的火行为，是火灾安全研究的一个重要内容。针对建筑物内火旋风的行为进行研究，提出了一种用于描述和表征建筑物内火旋风中心飘移的分析方法。结合此方法，应用大涡模拟技术对火旋风中心飘移现象进行了数值模拟研究，得到了火旋风中心飘移的平均角速度、温度峰值、高温中心位置等重要参数。

关键词：火旋风中心飘移大涡模拟建筑

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基于分形图案蚀刻屏蔽金属提高磁耦合能量传输效率

Qing-feng LI,Shao-bo CHEN,Wei-ming WANG,Hong-wei HAO,Lu-ming LI

《信息与电子工程前沿（英文）》 2016年第17卷第1期页码 74-82 doi: 10.1631/FITEE.1500114

摘要：薄金属板通常位于磁耦合能量传输（MCET）系统的耦合路径中。金属中的涡流会降低能量传输效率，甚至可能带来安全隐患。本文介绍了在金属中使用蚀刻的分形图案来抑制涡流并提高效率。仿真和实验结果表明该方法非常有效。分形图案应满足三个特征，即，破坏金属边缘，在高强度磁场区域中进行蚀刻以及在厚度方向上贯穿金属进行蚀刻。不同的分形模式导致不同的结果。通过改变涡流分布，当金属表现出电阻效应时，分形图案槽可减少涡流损耗，而当金属表现出电感效应时，分形图案槽可抑制金属中的感应磁场。多层高电导率金属（例如Cu）中的分形图案缝隙显着降低了感应磁场强度。此外，随着蚀刻层数的增加，传递功率，传递效率，接收效率和涡流损耗都增加。这些结果可通过有效的能量传输和在金属屏蔽设备中的安全使用而使MCET受益。

关键词：分形几何；层状金属屏蔽；涡流效应；磁耦合能量传输

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瞬变电磁法用于检测与识别硐室爆破盲炮的可行性探讨

刘连生,梁龙华,吴吉洋,焦永斌,陆哲祥

《中国工程科学》 2014年第16卷第11期页码 107-112

摘要：

应用瞬变电磁法对硐室爆破盲炮的检测与识别进行了可行性研究。试验时先确立电磁背景场，然后在硐室中预置良性导体并测得电磁场后消除背景场，在爆破后再次进行瞬变电磁测量。通过对比爆破前后预置良性导体涡流场的变化，实现硐室爆破盲炮检测与识别的目的。试验结果表明，当铝箱目标体埋深不超过30 m时，瞬变电磁检测法可以明确地确定铝箱的位置；当铝箱埋深超过30 m后，铝箱形成的二次涡流场层次不明，不能确定铝箱的埋深与位置。

关键词：瞬变电磁法硐室爆破盲炮检测与识别涡流场目标体

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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

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

A dynamic procedure based on the scale-similarity hypotheses for large-eddy simulation

ZHOU Bing, CUI Guixiang, CHEN Naixiang

期刊论文

Numerical modeling of current-induced scour around multi-wall foundation using large-eddy simulation

期刊论文

Large eddy simulation of turbulent buffet forces in flow induced vibration

XI Zhide, CHENG Bingde, LI Pengzhou

期刊论文

Large eddy simulation of a 660 MW utility boiler under variable load conditions

Haoshu SHEN, Yuxin WU, Minmin ZHOU, Hai ZHANG, Guangxi YUE, Junfu LYU