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Stable Recovery of Low Rank Matrices From Nuclear Norm minimization

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Acta Mathematicae Applicatae Sinica 2015年第1期31卷 247-260页

作者： hui-min wang Song LI Department of Mathematics Shaoxing University Department of Mathematics Zhejiang University

Low rank matrix recovery is a new topic drawing the attention of many researchers which addresses the problem of recovering an unknown low rank matrix from few linear measurements. The matrix Dantzig selector and the matrix Lasso are two important algorithms based on nuclear norm minimization. In this paper, we first prove some decay properties of restricted isometry constants, then we discuss the recovery errors of these two algorithms and give a new bound of restricted isometry constant to guarantee stable recovery, which improves the results of [11].

关键词： restricted isometry constants nuclear norm minimization low rank matrices

Numerical simulation of low-Reynolds number flows past two tandem cylinders of different diameters

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Water Science and Engineering 2013年第4期6卷 433-445页

作者： Yong-tao wang Zhong-min YAN hui-min wang College of Environmental Science and Engineering Suzhou University of Science and Technology College of Water Conservancy and Hydropower Engineering Hohai University College of Environment Hohai University

The flow past two tandem circular cylinders of different diameters was simulated using the finite volume method. The diameter of the downstream main cylinder （D） was kept constant, and the diameter of the upstream control cylinder （d） varied from 0.1D to D. The studied Reynolds numbers based on the diameter of the downstream main cylinder were 100 and 150. The gap between the control cylinder and the main cylinder （G） ranged from 0.1D to 4D. It is concluded that the gap-to-diameter ratio （G/D） and the diameter ratio between the two cylinders （d/D） have important effects on the drag and lift coefficients, pressure distributions around the cylinders, vortex shedding frequencies from the two cylinders, and flow characteristics.

关键词： two tandem cylinders vortex shedding drag force lift force numerical simulation

The Crouzeix-Raviart Type Nonconforming Finite Element Method for the Nonstationary Navier-Stokes Equations on Anisotropic Meshes

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Acta Mathematicae Applicatae Sinica 2014年第1期30卷 145-156页

作者： Dong-yang SHI hui-min wang Department of Mathematics Zhengzhou University College of Science Henan Institute of Engineering

This paper is devoted to study the Crouzeix-Raviart （C-R） type nonconforming linear triangular finite element method （FEM） for the nonstationary Navier-Stokes equations on anisotropic meshes. By intro- ducing auxiliary finite element spaces, the error estimates for the velocity in the L2-norm and energy norm, as well as for the pressure in the L2-norm are derived.

关键词： Navier-Stokes equations C-R type nonconforming linear triangular FE anisotropic meshes error estimates

Optimization and coordination of South-to-North Water Diversion supply chain with strategic customer behavior

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Water Science and Engineering 2012年第4期5卷 464-477页

作者： Zhi-song CHEN hui-min wang Business School Nanjing Normal University State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Hohai University

The South-to-North Water Diversion （SNWD） Project is a significant engineering project meant to solve water shortage problems in North China. Faced with market operations management of the water diversion system, this study defined the supply chain system for the SNWD Project, considering the actual project conditions, built a decentralized decision model and a centralized decision model with strategic customer behavior （SCB） using a floating pricing mechanism （FPM）, and constructed a coordination mechanism via a revenue-sharing contract. The results suggest the following：（1） owing to water shortage supplements and the excess water sale policy provided by the FPM, the optimal ordering quantity of water resources is less than that without the FPM, and the optimal profits of the whole supply chain, supplier, and external distributor are higher than they would be without the FPM; （2） wholesale pricing and supplementary wholesale pricing with SCB are higher than those without SCB, and the optimal profits of the whole supply chain, supplier, and external distributor are higher than they would be without SCB; and （3） considering SCB and introducing the FPM help increase the optimal profits of the whole supply chain, supplier, and external distributor, and improve the efficiency of water resources usage.

关键词： South-to-North Water Diversion supply chain strategic customer behavior floatingpricing mechanism

A Survey on Recent Advances and Challenges in Reinforcement Learning Methods for Task-oriented Dialogue Policy Learning

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Machine Intelligence Research 2023年第3期20卷 318-334页

作者： Wai-Chung Kwan Hong-Ru wang hui-min wang Kam-Fai Wong The Systems Engineering and Engineering Management Department The Chinese University of Hong KongHong Kong 999077China

Dialogue policy learning(DPL)is a key component in a task-oriented dialogue(TOD)*** goal is to decide the next action of the dialogue system,given the dialogue state at each turn based on a learned dialogue *** learning(RL)is widely used to optimize this dialogue *** the learning process,the user is regarded as the environment and the system as the *** this paper,we present an overview of the recent advances and challenges in dialogue policy from the perspective of *** specifically,we identify the problems and summarize corresponding solutions for RL-based dialogue policy *** addition,we provide a comprehensive survey of applying RL to DPL by categorizing recent methods into five basic elements in *** believe this survey can shed light on future research in DPL.

关键词： Dialogue policy learning(DPL) task-oriented dialogue system(TOD) reinforcement learning(RL) dialogue system Markov decision process

Refill Friction Stir Spot Welding of Similar and Dissimilar Alloys:A Review

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Acta Metallurgica Sinica(English Letters) 2020年第1期33卷 30-42页

作者： Xiao-Song Feng Song-Bin Li Li-Na Tang hui-min wang Shanghai Aerospace Equipments Manufacturer Co. LtdShanghai 200245China National Center for Materials Service Safety University of Science and TechnologyBeijingBeijing 100083China

Refi ll friction stir spot welding,also known as friction spot welding(FSpW),is a solid-state welding process suitable for spot joining of lightweight *** the eff orts of improving joint quality for similar and dissimilar materials,for example,aluminum and magnesium,this joining technology is well *** joining mechanism and process characteristics of FSpW have been widely ***,the application of FSpW in industry has not been entirely *** this review article,the research of similar and dissimilar material joints,such as,Al/Cu,Al/Ti,Al/Mg and Al/Steel,is *** microstructural features and mechanical properties of the joints,welding tool and the application development are discussed in detail.

关键词： Refill friction stir spot welding Dissimilar joints Microstructure Mechanical properties Welding parameters

Effects of Nitrogen Content and Austenitization Temperature on Precipitation in Niobium Micro-alloyed Steels

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Journal of Iron and Steel Research International 2015年第12期22卷 1164-1173页

作者： Lei CAO Zhong-min YANG Ying CHEN hui-min wang Xiao-li ZHAO Central Iron and Steel Research Institute

The influences of nitrogen content and austenitization temperature on Nb（C, N） precipitation in niobium micro-alloyed steels were studied by different methods： optical microscopy, tensile tests, scanning electron mi- croscopy, transmission electron microscopy, physicochemical phase analysis, and small-angle X-ray scattering. The results show that the strength of the steel with high nitrogen content is slightly higher than that of the steel with low nitrogen content. The increase in the nitrogen content does not result in the increase in the amount of Nb（C,N） precipitates, which mainly depends on the niobium content in the steel. The mass fraction of small-sized Nb（C, N） precipitates （1--10 nm） in the steel with high nitrogen content is less than that in the steel with low nitrogen con- tent. After austenitized at 1 150 ℃, a number of large cuboidal and needle-shaped particles are detected in the steel with high nitrogen content, whereas they dissolve after austenitized at 1 200 ℃ and the Nb（C,N） precipitates become finer in both steels. Furthermore, the results also show that part of the nitrogen in steel involves the formation of al- loyed cementite.

关键词： nitrogen content austenitization temperature l Nb(C,N) preeipitation alloyed cementite

Forecasting fierce floods with transferable AI in data-scarce regions

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The Innovation 2024年第4期5卷 17-18页

作者： hui-min wang Xiao Peng Xiaogang He Department of Civil and Environmental Engineering National University of SingaporeSingapore 117576Singapore

Flooding is one of the most devastating natural disasters that affects communities *** early May 2023,catastrophic floods swept through Rwanda and the Democratic Republic of the Congo,leading to over 600 deaths and displacing *** climate change is supercharging extreme rainfall worldwide,similar floods could further *** developing regions with limited resources to build flood defenses,accurate flood forecasting with sufficient lead time is a cost-effective adaptation strategy to mitigate flood ***,the lack of ground measurements in these regions hinders our understanding of flood-generating mechanisms,thereby limiting our ability to build better models for improved flood forecasts.

关键词： flood floods thereby

Fe_(2)Mn(μ_(3)-O)(COO)_(6) Cluster Based Stable MOF for Oxidative Coupling of Amines via Heterometallic Synergy

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Chinese Journal of Chemistry 2021年第11期39卷 2983-2989页

作者： Ying-Xia wang hui-min wang Pan Meng Dong-Xia Song Zhikai Qi Xian-ming Zhang Key Laboratory of Magnetic Molecules and Magnetic Information Materials(ministry of Education) Institute of Chemistry and CultureSchool of Chemistry and Material ScienceShanxi Normal UniversityLinfenShanxi041004 China College of Chemistry&Chemical Engineering Key Laboratory of Interface Science and Engineering in Advanced MaterialMinistry of EducationTaiyuan University of TechnologyNo.79 Yingze WestTaiyuanShanxi030024 China

The direct catalytic oxidative coupling of amines is one of the attracting methods for the synthesis of a variety of pharmaceutical or industrial needed *** earth-abundant manganese based salts,oxides,and complexes have been applied in this ***,these compounds suffered from difficult separation,large catalyst loading,complicated reactivation or indeterminate *** the facts that metal-organic frameworks(MOFs)with crystalline structure,precise composition,and enormous surface area have superior performance in heterogeneous catalytic reactions,herein,we introduced Mn into[Fe_(3)(μ_(3)-O)(CH_(3)COO)_(6)],one of the precursors for the preparation of stable MOFs,and got[Fe_(2)Mn(μ_(3)-O)(CH_(3)COO)_(6)]*** ligand replacement with biphenyl-3,4’,5-tricarboxylic acid(BPTC),heterometallic cluster-based[Fe_(2)Mn(μ_(3)-O)(BPTC)2(DMF)2(H_(2)O)](1)was *** expected,1 is stable and able to catalyze the homo-or cross-coupling of amines effectively and selectively with 0.9 mol%catalyst loading at room *** experiments indicated that the catalytic activity of 1 mainly stems from Mn sites and that Fe synergistically contributes to the ***,1 is recyclable and can be reused easily for at least 8 runs without obvious decrease in catalytic *** our knowledge,1 should be the first heterometallic cluster-based MOF with defined structure suitable for the synthesis of diverse imines from oxidative coupling of amines under mild conditions,which may shed light on the easy preparation of effective heterogeneous catalysts for organic synthesis.

关键词： Amines Metal-organic frameworks Manganese Oxidative coupling Heterometallic synergy