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Assessment of first-order-moment-based sample reconstruction method for design flood estimation in changing environment

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Water Science and Engineering 2023年第3期16卷 226-233页

作者： yi-ming Hu Zhong-min Liang yi-xin huang Jun Wang Bin-quan Li College of Hydrology and Water Resources Hohai UniversityNanjing 210098China

Estimating the design flood under nonstationary conditions is challenging. In this study, a sample reconstruction approach was developed to transform a nonstationary series into a stationary one in a future time window (FTW). In this approach, the first-order moment (EFTW) of an extreme flood series in the FTW was used, and two possible methods of estimating EFTW values in terms of point values and confidence intervals were developed. Three schemes were proposed to analyze the uncertainty of design flood estimation in terms of sample representativeness, uncertainty from EFTW estimation, and both factors, respectively. To investigate the performance of the sample reconstruction approach, synthesis experiments were designed based on the annual peak series of the Little Sugar Creek in the United States. The results showed that the sample reconstruction approach performed well when the high-order moment of the series did not change significantly in the specified FTW. Otherwise, its performance deteriorated. In addition, the uncertainty of design flood estimation caused by sample representativeness was greater than that caused by EFTW estimation.

关键词： Hydrological frequency analysis Nonstationarity Series reconstruction Uncertainty assessment Changing environment

Phase transformation-induced Mg isotope fractionation in Mgmediated CaCO_(3)mineralization

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Nano Research 2023年第2期16卷 3597-3602页

作者： yi-ming Ju Fang huang Xin Ding Li-Bo Mao Shu-Hong Yu Department of Chemistry Institute of Biomimetic Materials&ChemistryAnhui Engineering Laboratory of Biomimetic MaterialsDivision of Nanomaterials&ChemistryHefei National Research Center for Physical Sciences at the MicroscaleUniversity of Science and Technology of ChinaHefei 230026China CAS Key Laboratory of Crust-Mantle Materials and Environments School of Earth and Space SciencesUniversity of Science and Technology of ChinaHefei 230026China CAS Center for Excellence in Comparative Planetology University of Science and Technology of ChinaHefei 230026China

The biomineralization of CaCO_(3)often involves the transformation of amorphous precursors into crystalline phases,which is regulated by various proteins and inorganic ions such as Mg^(2+)*** the effects of Mg^(2+)ions on the polymorph and shape of the crystalline CaCO_(3)have been observed and studied,the interplay between Mg^(2+)ions and CaCO_(3)during the mineralization remains *** work focuses on the mechanism of Mg^(2+)ion-regulated mineralization of CaCO_(3).By tracing the Mg isotope fractionation,the different mineralization pathways of CaCO_(3)under different Mg^(2+)ion concentrations had been *** regulatory role of Mg^(2+)ions at the different stages of mineralization had been proposed through combining the fractionation data with the analyses of the CaCO_(3)polymorph and shape *** results provide a clear view of the Mg-mediated crystallization process of amorphous CaCO_(3),which can be used to finely control the phase of the crystalline products according to different needs.

关键词： mineralization calcium carbonate magnesium isotope fractionation

石家庄S波段和X波段双偏振雷达定量降水估测应用研究

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高原气象 2025年第1期44卷 253-264页

作者：黄兆楚印佳楠杨洋张晓瑞黄毅王梧熠崔毅李禧亮河北省人工影响天气中心河北石家庄050021 河北省气象装备中心河北石家庄050021 河北省气象与生态环境重点实验室河北石家庄050021 石家庄市气象局河北石家庄050081

基于石家庄S波段雷达和X波段雷达、雨滴谱仪观测资料以及地面雨量计数据,分析两种雷达的R(ZH)、R(ZH,ZDR)、R(KDP)和R(KDP,ZDR)四种定量降水估测方法。结果表明,利用雨滴谱仪数据计算出的雷达反射率因子与雷达实测具有较好的一致性,但... 详细信息

基于石家庄S波段雷达和X波段雷达、雨滴谱仪观测资料以及地面雨量计数据,分析两种雷达的R(ZH)、R(ZH,ZDR)、R(KDP)和R(KDP,ZDR)四种定量降水估测方法。结果表明,利用雨滴谱仪数据计算出的雷达反射率因子与雷达实测具有较好的一致性,但整体偏大5 dB;两种雷达使用R(KDP,ZDR)方法估测降水结果优于其他方法,使用偏振参量KDP能明显提高降雨估测结果,使用ZDR后,测雨公式较单参量提高不明显;使用R(KDP)和R(KDP,ZDR)方法,利用X波段雷达估测降水的准确度略高于S波段雷达,可提升约10%,利用高空间分辨率的X波段雷达可以提升城市降水估测的精确度。

关键词：双偏振雷达雨滴谱定量估测降水(QPE)

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Theoretical Investigation of the Viscous Damping Coefficient of Hydraulic Actuators

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Chinese Journal of Mechanical Engineering 2017年第4期30卷 829-842页

作者： ming-Hui huang Qing Pan yi-Bo Li Peng-Da Ma Jun Ma State Key Laboratory of High Performance Complex Manufacturing Central South UniversityChangsha 410083HunanChina

The viscous damping coefficient （VDC） of hydraulic actuators is crucial for system modeling, control and dynamic characteristic analysis. Currently, the resear- ches on hydraulic actuators focus on behavior assessment, promotion of control performance and efficiency. However, the estimation of the VDC is difficult due to a lack of study. Firstly, using two types of hydraulic cylinders, behaviors of the VDC are experimentally examined with velocities and pressure variations. For the tested plunger type hydraulic cylinder, the exponential model B = αν-β （α 〉 0, β 〉 0） or B = α1e-β1ν＋α2e-β2ν（α1, α2 〉 0, β1,β2 〉 0）, fits the relation between the VDC and velocities for a given pressure of chamber with high precision. The magnitude of the VDC decreases almost linearly under certain velocities when increasing the chamber pressure from 0.6 MPa to 6.0 MPa. Furthermore, the effects of the chamber pressures on the VDC of piston and plunge type hydraulic cylinders are different due to different sealing types. In order to investi- gate the VDC of a plunger type hydraulic actuator drasti- cally, a steady-state numerical model has been developed to describe the mechanism incorporating tandem seal lubrica- tion, back-up ring related friction behaviors and shear stress of fluid. It is shown that the simulated results of VDC agreewith the measured results with a good accuracy. The pro- posed method provides an instruction to predict the VDC in system modeling and analysis.

关键词： Hydraulic actuator Viscous dampingcoefficient Friction Tandem seal

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激光的双光栅移频效应理论及应用

中国激光 1985年第6期 343-345页

作者：韩光耀张毓昌易明黄宗华杨选民南京大学物理系

分析了激光的双光栅移频效应,并作了实验验证.这一效应可用来测量小位移量或速度值,比表氏干涉仪简单易调,并已试用于穆氏谱仪上测定振动速度,效果理想.

关键词：双光栅移频衍射光激光

Data-driven simultaneous vertex and energy reconstruction for large liquid scintillator detectors

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Nuclear Science and Techniques 2023年第6期34卷 103-113页

作者： Gui-Hong huang Wei Jiang Liang-Jian Wen yi-Fang Wang Wu-ming Luo School of Applied Physics and Materials Wuyi UniversityJiangmen529020China Institute of High Energy Physics Chinese Academy of SciencesBeijing100049China School of Physical Sciences University of Chinese Academy of ScienceBeijing100049China

High-precision vertex and energy reconstruction are crucial for large liquid scintillator detectors such as that at the Jiangmen Underground Neutrino Observatory(JUNO),especially for the determination of neutrino mass ordering by analyzing the energy spectrum of reactor *** paper presents a data-driven method to obtain a more realistic and accurate expected PMT response of positron events in JUNO and develops a simultaneous vertex and energy reconstruction method that combines the charge and time information of *** the JUNO detector,the impact of the vertex inaccuracy on the energy resolution is approximately 0.6%.

关键词： JUNO Liquid scintillator detector Neutrino experiment Vertex reconstruction Energy reconstruction

Deep reinforcement learning:a survey

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Frontiers of Information Technology & Electronic Engineering 2020年第12期21卷 1726-1744页

作者： Hao-nan WANG Ning LIU yi-yun ZHANG Da-wei FENG Feng huang Dong-sheng LI yi-ming ZHANG Science and Technology on Parallel and Distributed Processing Laboratory National University of Defense TechnologyChangsha 41OOOOChina

Deep reinforcement learning(RL)has become one of the most popular topics in artificial intelligence *** has been widely used in various fields,such as end-to-end control,robotic control,recommendation systems,and natural language dialogue *** this survey,we systematically categorize the deep RL algorithms and applications,and provide a detailed review over existing deep RL algorithms by dividing them into modelbased methods,model-free methods,and advanced RL *** thoroughly analyze the advances including exploration,inverse RL,and transfer ***,we outline the current representative applications,and analyze four open problems for future research.

关键词： Reinforcement learning Deep reinforcement learning Reinforcement learning applications

豆浆中风味物质形成、与蛋白的互作机制及生物法改善豆浆风味的研究进展

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食品科学 2025年第2期46卷 280-289页

作者：高宇齐宝坤廖一闫世长李杨黄雨洋东北农业大学食品学院黑龙江哈尔滨150030 哈尔滨商业大学食品工程学院黑龙江哈尔滨150028

豆浆作为一种营养丰富的植物基蛋白饮品,在全球范围内受到消费者的喜爱。然而,其特有的不良风味往往影响消费者的接受度,限制了豆浆产品的市场推广。本文探讨豆浆中风味物质的形成机理、这些风味物质与豆浆中的蛋白质之间的相互作用机... 详细信息

豆浆作为一种营养丰富的植物基蛋白饮品,在全球范围内受到消费者的喜爱。然而,其特有的不良风味往往影响消费者的接受度,限制了豆浆产品的市场推广。本文探讨豆浆中风味物质的形成机理、这些风味物质与豆浆中的蛋白质之间的相互作用机制以及通过生物方法改善豆浆风味的研究进展。通过无脂氧合酶大豆品种的开发、酶处理和微生物发酵等生物方法,可以有效地改善豆浆的风味,同时保持其营养价值。最后对未来改善豆浆风味的研究方向做出展望,以期为豆浆及其制品的品质提升和市场推广提供理论依据,为推动我国大豆制品市场的发展做出贡献。

关键词：豆浆风味物质-蛋白质互作生物方法风味改良

Mechanistic Drifting Forecast Model for A Small Semi-Submersible Drifter Under Tide–Wind–Wave Conditions

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China Ocean Engineering 2018年第1期32卷 99-109页

作者： ZHANG Wei-na huang Hui-ming WANG yi-gang CHEN Da-ke ZHANG lin Key Laboratory of Coastal Disaster and Defence Ministry of Education Hohai University College of Harbour Coastal and offshore Engineering Hohai University

Understanding the drifting motion of a small semi-submersible drifter is of vital importance regarding monitoring surface currents and the floating pollutants in coastal regions. This work addresses this issue by establishing a mechanistic drifting forecast model based on kinetic analysis. Taking tide–wind–wave into consideration, the forecast model is validated against in situ drifting experiment in the Radial Sand Ridges. Model results show good performance with respect to the measured drifting features, characterized by migrating back and forth twice a day with daily downwind displacements. Trajectory models are used to evaluate the influence of the individual hydrodynamic forcing. The tidal current is the fundamental dynamic condition in the Radial Sand Ridges and has the greatest impact on the drifting distance. However, it loses its leading position in the field of the daily displacement of the used drifter. The simulations reveal that different hydrodynamic forces dominate the daily displacement of the used drifter at different wind scales. The wave-induced mass transport has the greatest influence on the daily displacement at Beaufort wind scale 5–6; while wind drag contributes mostly at wind scale 2–4.

关键词： in situ drifting experiment mechanistic drifting forecast model tide–wind–wave coupled conditions small semi-submersible drifter daily displacement