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Monkeypox,wild animals,and potential big problem

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Zoological Research 2022年第4期43卷 612-614页

作者： Tian-zhang song Yong-Tang Zheng Key Laboratory of Animal Models and Human Disease Mechanisms of the Chinese Academy of Sciences KIZ-CUHK Joint Laboratory of Bioresources and Molecular Research in Common DiseasesKunming Institute of ZoologyChinese Academy of SciencesKunmingYunnan 650223China National Resource Center for Non-Human Primates National Research Facility for Phenotypic&Genetic Analysis of Model Animals(Primate Facility)Kunming Institute of ZoologyChinese Academy of SciencesKunmingYunnan 650107China

A new outbreak of monkeypox virus(MPV)is currently occurring in several regions of the *** the beginning of May 2022,3040 cases have been reported to the World Health Organization(WHO)*** of its usual“endemic”base in Africa,the virus has so far been detected in 47 countries,including in Europe,America,Oceania,and Asia,where monkeypox is uncommon or previously *** 25 June 2022,the WHO Emergency Committee declared that the outbreak does not currently constitute a Public Health Emergency of International Concern,but unanimously acknowledged the emergency nature of the event and that controlling further spread will require a vigorous ***,new cases of MPV infection have been confirmed in Korea,Singapore,and Taiwan,***,a better understanding of MPV and enhanced surveillance are essential for preventing disease recurrence.

关键词： globally Taiwan currently

Effect of conical intersection of benzene on non-adiabatic dynamics

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Chinese Physics B 2022年第8期31卷 367-371页

作者： Duo-Duo Li song zhang State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics Innovation Academy for Precision Measurement Science and TechnologyChinese Academy of SciencesWuhan 430071China University of Chinese Academy of Sciences Beijing 100049China

The effect of conical intersection on the excited dynamics of benzene is studied by ab initio theory of electronic structure,which provides an important insight into photophysical and photochemical *** on the CASSCF(6,6)/6-31+G(d,p)method,the topological structures of conical intersections S_(1)/S and S_(2)/S_(1)of benzene,as well as the optimal structures of the ground state(S)and excited states(S_(1),S_(2)),are *** energy minima of the S_(1)state and S_(2)state are estimated at 4.608 e V and 6.889 e V,*** addition,the energy values of the conical intersections of S_(1)/S and S_(2)/S_(1)are predicted to be 5.600 e V and 6.774 e *** to the topological structures and energy values of the S_(2)/S_(1)and S_(1)/S conical intersections,the photophysical behavior of benzene excited to the S_(2)state and the effects of the S_(2)/S_(1)and S_(1)/S conical intersections are discussed in detail.

关键词： conical intersection nonadiabatic dynamics ultrafast relaxation quantum chemical calculations

A Novel Attention-based Global and Local Information Fusion Neural Network for Group Recommendation

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Machine Intelligence Research 2022年第4期19卷 331-346页

作者： song zhang Nan Zheng Dan-Li Wang State Key Laboratory of Management and Control for Complex Systems Institute of AutomationChinese Academy of SciencesBeijing 100190China School of Artificial Intelligence University of Chinese Academy of SciencesBeijing 100049China

Due to the popularity of group activities in social media,group recommendation becomes increasingly *** aims to pursue a list of preferred items for a target *** deep learning-based methods on group recommendation have focused on learning group representations from single interaction between groups and ***,these methods may suffer from data sparsity *** for the interaction between groups and users,there also exist other interactions that may enrich group representation,such as the interaction between groups and *** interactions,which take place in the range of a group,form a local view of a certain *** addition to local information,groups with common interests may also show similar tastes on ***,group representation can be conducted according to the similarity among groups,which forms a global view of a certain *** this paper,we propose a novel global and local information fusion neural network(GLIF)model for group *** GLIF,an attentive neural network(ANN)activates rich interactions among groups,users and items with respect to forming a group′s local ***,our model also leverages ANN to obtain a group′s global representation based on the similarity among different ***,it fuses global and local representations based on attention mechanism to form a group′s comprehensive ***,group recommendation is conducted under neural collaborative filtering(NCF)*** experiments on three public datasets demonstrate its superiority over the state-of-the-art methods for group recommendation.

关键词： Group recommendation attentive neural network(ANN) global information local information recommender system

Study on oxygen transport and titanium oxidation in coating cracks under parallel gas flow based on LBM modelling

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Chinese Journal of Chemical Engineering 2023年第4期56卷 15-24页

作者： Shengfeng Luo song zhang Yiping Zeng Hui zhang Lili Zheng Zhaopeng Xu Department of Engineering Physics Tsinghua UniversityBeijing 100084China Department of Mechanics and Aerospace Engineering Southern University of Science and TechnologyShenzhen 518055China Institute for Aero Engine Tsinghua UniversityBeijing 100084China Shenzhen Smart Hua Information Technology Research Co. Ltd.Shenzhen 518000China School of Aerospace Engineering Tsinghua UniversityBeijing 100084China Chinese Academy of Agricultural Mechanization Sciences Beijing 100084China

The oxygen transportation from surrounding air to coating cracks is an important factor in the oxidation and ignition of titanium alloy. In this work, the oxygen transport and surface oxidation of titanium in inclined cracks of coating under parallel airflow are studied with the lattice Boltzmann method(LBM).A boundary scheme of LBM about surface reaction is developed. The conversion factors are utilized to build the relationship between the physical scale and the lattice scale. The reliability of the LBM model is validated by the finite element method(FEM). The results show that the convective mass transport driven by the surrounding airflow and the vortex structure formed inside the crack are the two significant factors that influence the oxygen transport in cracks. The convective mass transfer plays a major role in oxygen transport when the inclination angle of the crack is small. For the cases with a large inclination angle, the oxygen transfer from the top to the bottom of the crack is mainly controlled by mass diffusion mechanism. The oxygen concentration in inclined cracks is generally less than that in vertical cracks, and oxidation and ignition of the substrate titanium might be more likely to occur in relatively vertical cracks.

关键词： Coating crack Oxidation Transport Ignition Numerical simulation

Research progress on the hydrodynamic performance of water-air-bubble mixed flows around a ship

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Journal of Hydrodynamics 2022年第2期34卷 171-188页

作者： Zheng Li Xiao-song zhang De-cheng Wan Computational Marine Hydrodynamics Lab(CMHL) School of Naval ArchitectureOcean and Civil EngineeringShanghai Jiao Tong UniversityShanghai 200240China

The interaction between ship and surrounding fluids generates the water-air-bubble mixed flow laden with numerous droplets and *** water-air-bubble mixed flow is a complex multi-phase flow phenomenon,which involves intense air-water mixture,complex evolution of interface shape,interactions between multi-scale flow structures and strong turbulent *** on the field observations at sea,a large range of white water-air-bubble flow exists widely around a large-scale sailing ship,and directly affects the hydrodynamic performance of ship from various *** paper reviews the research progress of water-air-bubble mixed flow around a *** knowledge about the formation and evolution mechanism are introduced ***,the effects of the water-air-bubble mixed flow on ship performance are further reviewed,the main concerns are ship resistance,propulsion performance,slamming and ***,the future research prospects are summarized.

关键词： Water-air-bubble mixed flow ship resistance propulsion performance ship slamming characteristics maneuverability

Development of Texture Mapping Approaches for Additively Manufacturable Surfaces

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Chinese Journal of Mechanical Engineering 2022年第4期35卷 125-138页

作者： Bhupesh Verma Omid Zarei song zhang Johannes Henrich Schleifenbaum Chair for Digital Additive Production RWTH Aachen University52074 AachenGermany

manufacturing(AM)technologies have been recognized for their capability to build complex components and hence have ofered more freedom to designers for a long *** ability to directly use a computer-aided design(CAD)model has allowed for fabricating and realizing complicated components,monolithic design,reducing the number of components in an assembly,decreasing time to market,and adding performance or comfort-enhancing *** of the features that can be introduced for boosting a component functionality using AM is the inclusion of surface texture on a given *** inclusion is usually a difcult task as creating a CAD model resolving fne details of a given texture is difcult even using commercial software *** paper develops a methodology to include texture directly on the CAD model of a target surface using a patch-based sampling texture synthesis algorithm,which can be manufactured using *** for the texture generation algorithm can be either a physical sample or an image with heightmap *** heightmap information from a physical sample can be obtained by 3D scanning the sample and using the information from the acquired point *** obtaining the required inputs,the patches are sampled for texture generation according to non-parametric estimation of the local conditional Markov random feld(MRF)density function,which helps avoid mismatched features across the patch *** generating the texture,a design constraint to ensure AM producibility is considered,which is essential when manufacturing a component using,e.g.,Fused Deposition Melting(FDM)or Laser Powder Bed Fusion(LPBF).The generated texture is then mapped onto the surface using the developed distance and angle preserving mapping *** implemented algorithms can be used to map the generated texture onto a mathematically defned *** paper maps the textures onto fat,curved,and sinusoidal surfaces for *** the texture m

关键词： Texture synthesis Design for additive manufacturing Image processing Textured surface generation Texture mapping

Numerical techniques for coupling hydrodynamic problems in ship and ocean engineering

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Journal of Hydrodynamics 2020年第2期32卷 212-233页

作者： Xiao-song zhang Jian-hua Wang De-cheng Wan Computational Marine Hydrodynamics Lab(CMHL) State Key Laboratory of Ocean EngineeringSchool of Naval ArchitectureOcean and Civil EngineeringShanghai Jiao Tong UniversityShanghai200240China

Most hydrodynamic problems in ship and ocean engineering are complex and highly *** the trend of intelligent and digital design for ships and ocean engineering structures,comprehensive performance evaluation and optimization are of vital importance during *** this process,various coupling effects need to be accurately *** the significant progress of computational fluid dynamics(CFD),many advanced numerical models were proposed to simulate the complex coupling hydrodynamic problems in ship and ocean engineering *** this paper,five key coupling hydrodynamic problems are introduced,which are hull-propeller-rudder coupling,wave-floating structure coupling,aerodynamic-hydrodynamic coupling,fluid structure coupling and fluid-noise coupling,*** paper focuses on the numerical simulation techniques corresponding to each coupling problem,including the theories and the *** directions and conclusions are provided finally.

关键词： Coupling hydrodynamic problems numerical techniques ship and ocean engineering

The Preservation of 20^(th)-Century Architectural Heritage in China:Evolution and Prospects

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Built Heritage 2018年第2期2卷 4-16页

作者： song zhang College of Architecture and Urban Planning Tongji UniversityShanghaiChina

This article examines the fundamental meaning of 20^(th)-century architectural heritage by reviewing the formation of the concept by the International Council on Monuments and Sites(ICOMOS).It analyses the current state of conservation and potential threats to China’s built heritage,built environment,and cultural landscapes that are less than 50 years *** article presents a thorough review of the facilitating process of the regulative infrastructure of Chinese modern architecture *** makes a comparative study of several cities’urban heritage assessment criteria as well as the first and second inventories of China’s 20^(th)-century architectural *** article argues that conserving China’s 20^(th)-century heritage calls for a theoretical framework,which integrates value assessment and advancing the conservation mechanism for built *** doing so,the transition may be facilitated from focusing on World Heritage towards heritage of the everyday,which embodies collective memories,and from preserving iconic monuments towards comprehensively conserving the built heritage.

关键词： 20^(th)-century heritage recent past architectural heritage assessment criteria conservation instrument

Nonclassical Effects of a Four-Level Excited-Doublet Atom Model

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Communications in Theoretical Physics 2006年第6X期46卷 1069-1073页

作者： zhang Jian-song XU Jing-Bo Zhejlang Institute of Modern Physics and Department of Physics Zhejiang University Hangzhou 310027 China

We adopt a dynamical algebraic method to study a four-level excited-doublet atom model and obtain the explicit expressions of the time-evolution operator and the density operator for the system. The nonclassical effects of the system, such as collapses and revivals of the atomic inversion and squeezing of the radiation field, are also discussed.

关键词： atom-field interaction nonclassical effects