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Numerical Simulation of Water Entry of Wedges in Waves Using A CIPBased Model

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China Ocean Engineering 2021年第1期35卷 48-60页

作者： hu zi-jun ZHAO Xi-zeng LI Meng-yu ZHAO Xin YAO Wen-wei SHAO Jie Zhejiang Institute of Hydraulic and Estuary Hangzhou 310020China Ocean College Zhejiang UniversityZhoushan 316021China

In this study,the water entry of wedges in regular waves is numerically investigated by a two-dimensional in-house numerical *** numerical model based on the viscous Navier−Stokes(N−S)equations employs a high-order different method—the constrained interpolation profile(CIP)method to discretize the convection term.A Volume of Fluid(VOF)-type method,the tangent of hyperbola for interface capturing/slope weighting(THINC/SW)is employed to capture the free surface/interface,and an immersed boundary method is adopted to treat the motion of *** momentum source function derived from the Boussinesq equation is applied as an internal wavemaker to generate regular *** accuracy of the numerical model is validated in comparison with experimental results in the *** results of water entry in waves are provided in terms of the impact force of wedge,velocity and pressure distributions of *** attention is paid to the effects of wave parameters and the position of wedge impacting the water *** is found that the existence of waves significantly influences the velocity and pressure field of fluid and impact force on the wedges.

关键词： Water entry water wave wedge internal wave maker CIP method VOF method

Insight into Financial Support for Rural Land Circulation:A Case Study of China Taiwan

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Asian Agricultural Research 2012年第10期4卷 42-44页

作者： SHEN Qi hu zi-jun Chongqing Academy of Agricultural Sciences Chongqing Operations and Management Department People's Bank of China

Based on the background of the second rural land reform in China Taiwan, we analyzed financial support measures and their effects. It comes to the insight into financial support for rural land circulation in China Taiwan for the new round of rural land reform in China mainland. It is proposed to: (i) put forth effort on rural infrastructure construction with financial special fund as major support and credit fund from policy bank as supplementary support; (ii) improve rural land evaluation, registration and guarantee systems and set up special loan for land circulation, to solve the problem of shortage of fund for farmers purchasing land; (iii) grant operating loans for rural large planting and breeding farmer households, to accelerate land circulation becoming effective; (iv) establish development fund for agriculture, farmers and rural areas, to ensure sustainable input into rural areas.

关键词： China Taiwan China mainland Rural land circulation

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采用阵列天线的GPS接收机的多径抑制方法

宇航学报 2014年第7期35卷 843-849页

作者：王纯张林让胡子军西安建筑科技大学信息与控制工程学院西安710055 西安电子科技大学雷达信号处理国防重点实验室西安710071

提出一种新的用于阵列天线GPS接收机的多径抑制方法。考虑到通常GPS视线信号的来波方向与多径的来波方向不同,在每个导航数据符号位内测距(C/A)码重复,通过对阵列接收的信号矢量与它本身的延迟信号矢量互相关,提高接收机前端信噪比,再... 详细信息

提出一种新的用于阵列天线GPS接收机的多径抑制方法。考虑到通常GPS视线信号的来波方向与多径的来波方向不同,在每个导航数据符号位内测距(C/A)码重复,通过对阵列接收的信号矢量与它本身的延迟信号矢量互相关,提高接收机前端信噪比,再利用最大特征值法和前后向空间平滑技术准确地估计期望卫星视线信号(LOSS)的来波方向。最后综合多个GSC子阵列有效地降低了相关多径对码跟踪精度的影响。仿真结果显示,该方法能使接收机在与LOSS码同步前准确估计LOSS的角度信息,有效抑制相关多径,且鉴相结果准确。

关键词： GPS接收机盲多径抑制 (C A)码直视信号(LOSS)

利用多普勒信息的单步初始化GMCPHD滤波器

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系统工程与电子技术 2014年第11期36卷 2122-2126页

作者：胡子军张林让张鹏西安电子科技大学雷达信号处理国防科技重点实验室陕西西安710071

标准的带势概率假设密度(cardinalized probability hypothesis density,CPHD)滤波器是一个有效的多目标跟踪算法,但是它假定新生目标的强度函数先验已知,因而无法应用于新生目标在场景中任意位置出现的环境。针对此问题,提出一种单步... 详细信息

标准的带势概率假设密度(cardinalized probability hypothesis density,CPHD)滤波器是一个有效的多目标跟踪算法,但是它假定新生目标的强度函数先验已知,因而无法应用于新生目标在场景中任意位置出现的环境。针对此问题,提出一种单步初始化的高斯混合CPHD滤波器。该滤波器利用位置上远离当前时刻估计状态的观测值单步初始化新生目标。此外,多普勒信息一方面被用来初始化新生目标的速度,另一方面在滤波器更新步骤中,多普勒速度和位置观测信息采用串行更新方法处理。仿真结果表明,所提算法在目标数的估计精度和优化子模式分配距离方面优于已有算法。

关键词：多目标跟踪带势概率假设密度单步初始化多普勒信息

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园林绿化中植物配置的多样性问题

福建林业科技 2007年第2期34卷 240-242页

作者：胡自军河南科技大学林业职业学院河南洛阳471002

对园林绿化植物配置中存在的多样性问题进行了论述,从增加绿化植物种类,加强彩叶树种、开花树种、抗性树种以及攀缘植物和地被植物的应用等方面总结了园林植物配置中应当注意的问题,并进一步分析了园林绿化中丰富植物品种的途径。

关键词：园林绿化植物配置多样性

Effect of cholesterol metabolism on hepatolithiasis

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World Journal of Gastroenterology 2025年第1期31卷 157-162页

作者： Lin Zheng zi-Yu Ye jun-Ji Ma Department of Gastroenterology The Second Hospital of Hebei Medical UniversityHebei Key Laboratory of GastroenterologyHebei Institute of GastroenterologyHebei Clinical Research Center for Digestive DiseasesNo.215 Heping West RoadShijiazhuang 050000Hebei ProvinceChina

Surgical intervention is currently the primary treatment for hepatolithiasis;how-ever,some patients still experience residual stones and high recurrence rates after *** metabolism seems to play an important role in hepatoli-thiasis pathogenesis.A high cholesterol diet is one of the significant reasons for the increasing incidence of ***,regular diet and appropriate medical intervention are crucial measures to prevent hepatolithiasis and reduce recurrence rate after *** dietary cholesterol and drugs that increase cholesterol stone solubility are key therapeutic approaches in treating *** article discusses the cholesterol metabolic pathways related to the pathogenesis of hepatolithiasis,as well as food intake and targeted therapeutic drugs.

关键词： Hepatolithiasis Cholesterol metabolism High-fat diet 3-hydroxy-3-methylglutaryl-coenzyme A reductase Interlobular bile duct

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涡判据在孔腔涡旋流动拓扑结构分析中的应用

船舶力学 2012年第8期16卷 839-846页

作者：胡子俊张楠姚惠之杨子轩中国船舶科学研究中心江苏无锡214082 清华大学工程力学系北京100084

涡作为一种经典的流动现象目前仍没有严格的数学定义,涡判据是人们识别涡的重要途径。文章对涡的各种判据及其物理意义进行了调研和总结,并将目前较为常用的Q判据和λ2判据应用于二维和三维孔腔流动中涡的识别,并对其拓扑结构进行了分析... 详细信息

涡作为一种经典的流动现象目前仍没有严格的数学定义,涡判据是人们识别涡的重要途径。文章对涡的各种判据及其物理意义进行了调研和总结,并将目前较为常用的Q判据和λ2判据应用于二维和三维孔腔流动中涡的识别,并对其拓扑结构进行了分析,得到了有意义的结果。

关键词：涡判据涡旋拓扑结构孔腔

基于高斯混合带势概率假设密度滤波器的未知杂波下多机动目标跟踪算法

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电子与信息学报 2015年第1期37卷 116-122页

作者：胡子军张林让张鹏王纯西安电子科技大学雷达信号处理国家重点实验室西安710071 西安建筑科技大学信息与控制工程学院西安710055

多模型的随机有限集(RFS)类方法是一类有效的多机动目标跟踪算法,但是现有算法都假定杂波统计特性先验已知,不适用于未知杂波背景。该文以高斯混合带势概率假设密度滤波器(GMCPHDF)为基础,提出一种未知杂波下的多机动目标跟踪算法。该... 详细信息

多模型的随机有限集(RFS)类方法是一类有效的多机动目标跟踪算法,但是现有算法都假定杂波统计特性先验已知,不适用于未知杂波背景。该文以高斯混合带势概率假设密度滤波器(GMCPHDF)为基础,提出一种未知杂波下的多机动目标跟踪算法。该算法对目标和杂波分别独立建模,通过最优高斯(BFG)估计方法对真实目标的强度函数进行预测,从而使多目标强度函数独立于机动目标的运动模型,实现各时刻真实目标的强度函数、杂波源期望个数以及真实目标和杂波源的混合势分布的迭代。仿真结果表明,该算法能够有效地联合估计多机动目标状态以及杂波期望个数。

关键词：多机动目标跟踪未知杂波带势概率假设密度滤波器最优高斯估计

Spin-glass behavior in the competing CoCrGaO_(4)cubic spinel system

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Nano Research 2025年第1期18卷 501-507页

作者： Jiyu hu Jiangli Ni Zhenfa zi Chaocheng Liu School of Physics and Materials Engineering Hefei Normal UniversityHefei 230009China National Synchrotron Radiation Laboratory University of Science and Technology of ChinaHefei 230026China

Spin glasses(SGs),generally defined as disordered systems with randomized competing interactions,are widely investigated complex *** the ground states of spin glasses is crucial for understanding the nature of disordered magnets and many other physical manifestations,while also helping to solve some hard combinatorial optimization problems across multiple ***,the intrinsic cause of SG has always been elusive,especially in spinel oxide ***,we report the SG behavior observed in the cubic spinel oxides CoCrGaO_(4),and provide a comprehensive understanding of its intrinsic *** results indicate a frustrated state under multi-magnetic competition,and the features of SG are confirmed by susceptibility *** fitting parameters ofτ0,T0,and zv of isothermal remanent magnetization further reveal the relaxation behavior and strong spin ***,the varying exchange coupling under different temperatures and magnetic fields is unveiled,which should be responsible for the disordered *** studies unravel the underlying mechanism responsible for doping-induced magnetic frustration and introduce CoCrGaO_(4)as a potential platform for investigating spin glass behavior,thereby advancing fundamental research on frustrated magnetism within the spinel system.

关键词： spin glass(SG) magnetic frustration magnetic competition spinel ferrites