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THE SLOP FLUX METHOD FOR NUMERICAL BALANCE IN USING ROE'S APPROXIMATE RIEMANN SOLVER

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Journal of Hydrodynamics 2012年第1期24卷 58-64页

作者： wang dang-wei LIU Xiao-fang CHEN Jian-guo JI Zu-wen State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin China Institute of Water Resources and Hydropower ResearchBeijing 100038China Institute of Geographic Sciences and Natural Resources Research Chinese Academy of SciencesBeijing 100101China Graduate University of the Chinese Academy of Sciences Beijing 100049China State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin China Institute of WaterResources and Hydropower ResearchBeijing 100038China

Imbalance arises when the Roe＇s method is directly applied in the shallow water *** reasons are different for the continuity equation and the momentum *** on the Roe＇s method,a partial surface method is proposed for a perfect balance for the continuity *** order to generate a mathematically hyperbolic formulation,the momentum equations are split,which causes incompatibility in the calculation of the momentum *** this article a numerical approach named the Slop Flux Method（SFM）is proposed to balance the source terms and the flux gradient based on the finite volume *** method is first applied to shallow water *** model is verified by analytical results of classical test cases with good *** the method is applied to a steady flow simulation over a practical complicated topography and the result shows good balance and conservation.

关键词： shallow water simulation Roe's method complicated topography partial surface method bed slop flux method

NUMERICAL SIMULATION OF LEVEE BREACH FLOWS UNDER COMPLEX BOUNDARY CONDITIONS

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Journal of Hydrodynamics 2009年第5期21卷 633-639页

作者： YU Ming-hui DENG Yin-ling QIN Lian-chao wang dang-wei CHEN Ya-ling State Key Laboratory of Water Resources and Hydropower Engineering Science Wuhan University Wuhan 430072 China

Levee or dam failure can cause a significant disaster in most cases. A good prediction of the flood process especially in a real complex terrain is necessary for working out emergency plans for levee or dam breaches. Numerical simulations of levee or dam breach flow were carried out often with constant flow parameters and in relatively simple channels rather than in natural rivers with complex boundaries. This article presents our dedicated studies on the 2-D numerical model of levee or dam breach hydraulics with finite difference schemes. The good performance of the model is demonstrated by comparisons with the theoretical solution of an idealized dam-break flow over a frictionless flat rectangular channel. The model is also validated through its stability and conservation properties. The model is applied to simulate the flood propagation under complex boundary conditions, and the unsteady flood process in a river and in the dry floodplain with a complex bed terrain simultaneously. Furthermore, with respect to engineering practice, the numerical solutions can give special guidance to the effects of parameters such as the flood depth at different sites and the inundated area at different time periods after the levee breach and the travel time of the flood waves, which may be very important for practicing engineers in an efficient flood management.

关键词： numerical simulation levee breach unsteady flood process complex boundary condition

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一种基于互相关处理的极点提取新算法

电子学报 2005年第6期33卷 1015-1018页

作者：王党卫粟毅马兴义国防科技大学电子科学与工程学院湖南长沙410073

针对传统极点提取算法在低信噪比时估计性能严重退化的缺点,该文从理论上推导了指数衰减正弦和信号在互相关处理后仍可表示为指数衰减正弦和信号的条件,定义了一种新的信号互相关函数估计方法,在此基础上提出了使用互相关消噪作为预处... 详细信息

针对传统极点提取算法在低信噪比时估计性能严重退化的缺点,该文从理论上推导了指数衰减正弦和信号在互相关处理后仍可表示为指数衰减正弦和信号的条件,定义了一种新的信号互相关函数估计方法,在此基础上提出了使用互相关消噪作为预处理的信号极点提取新方法.仿真实验表明,在相同精度的条件下文中提出的新方法较之改进KT法和基于四阶累量方法需要的信噪比降低了5dB.

关键词：指数衰减正弦瓦相关估计极点提取

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分布式OFDM-MIMO雷达MTI处理

系统工程与电子技术 2016年第8期38卷 1794-1799页

作者：谷文堃王党卫马晓岩空军预警学院三系湖北武汉430019

分布式频分正交复用-多输入多输出雷达(orthogonal frequency division multiplexing-multiple input multiple output,OFDM-MIMO)是一种新型雷达系统。针对该雷达的杂波抑制问题,建立了该雷达的回波模型,分析了空间分集和发射频率分集... 详细信息

分布式频分正交复用-多输入多输出雷达(orthogonal frequency division multiplexing-multiple input multiple output,OFDM-MIMO)是一种新型雷达系统。针对该雷达的杂波抑制问题,建立了该雷达的回波模型,分析了空间分集和发射频率分集对改善因子的影响,给出了该雷达的动目标显示(meving target indication,MTI)杂波抑制方法,并分析了提出方法的性能。较之传统发射相同载频信号的MIMO雷达,分布式OFDM-MIMO雷达由于频率分集带来的处理自由度能改善多普勒频率落入MTI滤波器凹口的目标的检测能力。理论和仿真实验证实了提出方法的有效性。

关键词：多输入多输出雷达分布式雷达频分正交复用动目标显示改善因子

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宽带MIMO雷达的阵列设计和成像方法

系统工程与电子技术 2010年第12期32卷 2541-2546页

作者：陈阿磊王党卫马晓岩粟毅空军雷达学院研究生队湖北武汉430019 空军雷达学院空/天机预警监视装备系湖北武汉430019 国防科学技术大学电子科学与工程学院湖南长沙430073

为了降低多输入多输出(multiple-input and multiple-output,MIMO)成像雷达的阵列规模和系统硬件的复杂性,结合宽带MIMO雷达发射/接收阵元的角度分集和信号分集特性,提出了一种基于双均匀线阵组合的非线性阵列模型,并给出了该阵列的设... 详细信息

为了降低多输入多输出(multiple-input and multiple-output,MIMO)成像雷达的阵列规模和系统硬件的复杂性,结合宽带MIMO雷达发射/接收阵元的角度分集和信号分集特性,提出了一种基于双均匀线阵组合的非线性阵列模型,并给出了该阵列的设计准则。不同于基于实孔径均匀阵列的宽带MIMO雷达成像系统,提出的非线性阵列模型可有效增加虚拟阵元个数和扩展阵列孔径,在不改变目标方位向成像质量条件下能有效降低实孔径均匀线阵的阵列规模和系统硬件的复杂度。同时,该阵列设计易于操作和实现。最后,仿真实验对该阵列模型的有效性进行了验证。

关键词：多输入多输出逆合成孔径雷达后向投影算法雷达成像

Boosting Oxygen Evolution Reaction Performance on NiFe‑Based Catalysts Through d‑Orbital Hybridization

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Nano-Micro Letters 2025年第1期17卷 281-292页

作者： Xing wang wei Pi Sheng Hu Haifeng Bao Na Yao wei Luo State Key Laboratory of New Textile Materials and Advanced Processing Technology Key Laboratory of New Textile Materials and Applications of Hubei ProvinceSchool of Materials Science and EngineeringWuhan Textile UniversityWuhan 430200People’s Republic of China College of Chemistry and Molecular Sciences Wuhan UniversityWuhan 430072People’s Republic of China

Anion-exchange membrane water electrolyzers(AEMWEs)for green hydrogen production have received intensive attention due to their feasibility of using earth-abundant NiFe-based *** introducing a third metal into NiFe-based catalysts to construct asymmetrical M-NiFe units,the d-orbital and electronic structures can be adjusted,which is an important strategy to achieve sufficient oxygen evolution reaction(OER)performance in ***,the ternary NiFeM(M:La,Mo)catalysts featured with distinct M-NiFe units and varying d-orbitals are reported in this *** and theoretical calculation results reveal that the doping of La leads to optimized hybridization between d orbital in NiFeM and 2p in oxygen,resulting in enhanced adsorption strength of oxygen intermediates,and reduced rate-determining step energy barrier,which is responsible for the enhanced OER *** critically,the obtained NiFeLa catalyst only requires 1.58 V to reach 1 A cm^(−2) in an anion exchange membrane electrolyzer and demonstrates excellent long-term stability of up to 600 h.

关键词： NiFe-based catalysts d-orbital coupling Oxygen evolution reaction Anion exchange membrane electrolyzer

AI-Enhanced Secure Data Aggregation for Smart Grids with Privacy Preservation

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Computers, Materials & Continua 2025年第1期82卷 799-816页

作者： Congcong wang Chen wang Wenying Zheng wei Gu School of Software Nanjing University of Information Science and TechnologyNanjing210044China School of Information Science and Engineering Zhejiang Sci-Tech UniversityHangzhou310018China State Key Laboratory of Public Big Data Guizhou UniversityGuiyang550025China School of Computer Science and Technology(School of Artificial Intelligence) Zhejiang Sci-Tech UniversityHangzhou310018China School of Computer Science(School of Cyber Science and Engineering) Nanjing University of Information Science and TechnologyNanjing210044China

As smart grid technology rapidly advances,the vast amount of user data collected by smart meter presents significant challenges in data security and privacy *** research emphasizes data security and user privacy concerns within smart ***,existing methods struggle with efficiency and security when processing large-scale *** efficient data processing with stringent privacy protection during data aggregation in smart grids remains an urgent *** paper proposes an AI-based multi-type data aggregation method designed to enhance aggregation efficiency and security by standardizing and normalizing various data *** approach optimizes data preprocessing,integrates Long Short-Term Memory(LSTM)networks for handling time-series data,and employs homomorphic encryption to safeguard user *** also explores the application of Boneh Lynn Shacham(BLS)signatures for user *** proposed scheme’s efficiency,security,and privacy protection capabilities are validated through rigorous security proofs and experimental analysis.

关键词： Smart grid data security privacy protection artificial intelligence data aggregation

两种基于MIMO雷达体制的鲁棒CFAR检测器

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电子与信息学报 2009年第3期31卷 596-600页

作者：王敦勇马晓岩袁俊泉王党卫空军雷达学院武汉430019

针对MIMO雷达的体制特点,该文提出了两种有序统计与均值相给合的MIMO雷达CFAR检测器(OSCA-CFAR和LCIOSCA-CFAR),给出了虚警概率与检测概率的表达式,然后在各种杂波背景下对检测器性能进行了仿真分析,并与经典的CA-CFAR检测器进行比较,... 详细信息

针对MIMO雷达的体制特点,该文提出了两种有序统计与均值相给合的MIMO雷达CFAR检测器(OSCA-CFAR和LCIOSCA-CFAR),给出了虚警概率与检测概率的表达式,然后在各种杂波背景下对检测器性能进行了仿真分析,并与经典的CA-CFAR检测器进行比较,仿真结果表明,OSCA-CFAR和LCIOSCA-CFAR检测器在均匀背景下较CA-CFAR有较小损失,在多目标干扰环境较CA-CFAR性能改善明显,在实际背景中具有更强的鲁棒性。最后比较了OSCA-CFAR和LCIOSCA-CFAR检测器的优缺点。

关键词： MIMO雷达 OSCA-CFAR LCIOSCA-CFAR 检测性能

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中段弹头IMM-EKF跟踪方法及性能分析

弹道学报 2016年第4期28卷 17-23页

作者：熊智敏王党卫马晓岩空军预警学院三系武汉430019

为了提高中段弹头跟踪收敛速度以及跟踪精度,提出了一种基于交互多模型(IMM)的扩展卡尔曼滤波(Extended Kalman Filter,EKF)的跟踪算法。基于中段弹头加速度变化特点,建立了目标的中段系统动力学模型及量测模型,通过引入速度测量值,使用... 详细信息

为了提高中段弹头跟踪收敛速度以及跟踪精度,提出了一种基于交互多模型(IMM)的扩展卡尔曼滤波(Extended Kalman Filter,EKF)的跟踪算法。基于中段弹头加速度变化特点,建立了目标的中段系统动力学模型及量测模型,通过引入速度测量值,使用IMM-EKF算法对中段目标进行跟踪。仿真结果表明,通过交互多模的非线性滤波算法,可以使中段跟踪收敛速度大为加快,速度测量值的引入也使得跟踪精度有所提高,并在弹头中段与再入段衔接处有较好的跟踪性能;验证了IMM-EKF跟踪中段弹头的有效性。

关键词：中段弹头跟踪交互多模型扩展卡尔曼滤波