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Advances in Applied Mathematics and Mechanics 2014年第5期6卷 637-662页

作者： Po-Wen Hsieh Suh-Yuh Yang cheng-shu you Department of Applied Mathematics Chung Yuan Christian UniversityJhongli CityTaoyuan County 32023Taiwan Department of Mathematics National Central UniversityJhongli CityTaoyuan County 32001Taiwan

This paper is devoted to a new high-accuracy finite difference scheme for solving reaction-convection-diffusion problems with a small diffusivityε.With a novel treatment for the reaction term,we first derive a difference scheme of accuracy O(ε^(2)h+εh^(2)+h^(3))for the 1-D *** the alternating direction technique,we then extend the scheme to the 2-D case on a nine-point *** apply the high-accuracy finite difference scheme to solve the 2-D steady incompressible Navier-Stokes equations in the stream function-vorticity *** examples are given to illustrate the effectiveness of the proposed difference *** made with some high-order compact difference schemes show that the newly proposed scheme can achieve good accuracy with a better stability。

关键词： Reaction-convection-diffusion equation incompressible Navier-Stokes equations boundary layer interior layer finite difference scheme

ADirect-Forcing Immersed Boundary Projection Method for Thermal Fluid-Solid Interaction Problems

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Advances in Applied Mathematics and Mechanics 2023年第1期15卷 1-29页

作者： cheng-shu you Po-Wen Hsieh Suh-Yuh Yang Department of Applied Mathematics Feng Chia UniversityXitun DistrictTaichung City 40724Taiwan Department of Applied Mathematics National Chung Hsing UniversitySouth DistrictTaichung City 40227Taiwan Department of Mathematics National Central UniversityJhongli DistrictTaoyuan City 32001Taiwan

In this paper,we develop a direct-forcing immersed boundary projection method for simulating the dynamics in thermal fluid-solid interaction *** underlying idea of the method is that we treat the solid as made of fluid and introduce two virtual forcing ***,a virtual fluid force distributed only on the solid region is appended to the momentum equation to make the region behave like a real solid body and satisfy the prescribed ***,a virtual heat source located inside the solid region near the boundary is added to the energy transport equation to impose the thermal boundary condition on the solid *** take the implicit second-order backward differentiation to discretize the time variable and employ the Choi-Moin projection scheme to split the coupled *** for spatial discretization,second-order centered differences over a staggered Cartesian grid are used on the entire *** advantages of this method are its conceptual simplicity and ease of *** experiments are performed to demonstrate the high performance of the proposed *** tests show that the spatial convergence rates of all unknowns seem to be super-linear in the 1-norm and 2-norm while less than linear in the maximum norm.

关键词： Fluid-solid interaction heat transfer direct-forcing method immersed boundary method projection scheme

ALANGEVIN TYPE PIEZOELECTRIC TRACKED TRAVELLING SYSTEM

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ALANGEVIN TYPE PIEZOELECTRIC TRACKED TRAVELLING SYSTEM

A TRACKED TRAVELLING SYSTEM UNDER THE ACTUATION OF A PIEZOELECTRIC TRANSDUCER

2015全国压电和声波理论及器件技术研讨会

作者： cheng-you shu Liang WANG Jia-mei JIN Jian-hui ZHANG State Key Laboratory of Mechanics and Control of Mechanical Structures Nanjing University of Aeronautics and Astronautics School of Mechanical and Electrical Engineering Guangzhou University

A novel tracked travelling system driven by a Langevin piezoelectric transducer is *** has advantages of large driving force,high mechanical integration,well reliability,requiring no lubrication,and having the potential application in planetary *** tracked travelling system comprises of an actuating mechanism and a *** actuating mechanism includes a Langevin piezoelectric transducer and two annular parts symmetrically placed at two ends of the *** track is pressed in contact to the outer surfaces of the annular *** rotating waves are generated in two annular parts,and then the microscopic elliptical motions at the outer surface of the annular parts will be generated to drive the track to move by friction *** actuating mechanism is analyzed by using FEM,and the simulation results are compared with the vibration measurements *** then the prototype of the tracked travelling system was assembled and investigated experimentally for its *** maximum average velocities to bi-directional movements were 72mm/s and 61.5mm/s under the excitation voltage of 500Vand frequency of 35.1 kHz,respectively.

关键词： Tracked travelling system Langevin piezoelectric transducer Experiments Planetary exploration

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A TRACKED TRAVELLING SYSTEM UNDER THE ACTUATION OF A PIEZOEL...

Research on the Safety Evaluation of a High-pressure Vessel in a Missile System

2015全国压电和声波理论及器件技术研讨会

作者： Liang WANG cheng-you shu Jia-mei JIN Jian-hui ZHANG State Key Laboratory of Mechanics and Control of Mechanical Structures Nanjing University of Aeronautics and Astronautics School of Mechanical and Electrical Engineering Guangzhou University

A novel type piezoelectric tracked travelling system with potential application to planetary exploration is *** tracked travelling system includes a piezoelectric transducer and a metal *** the piezoelectric transducer is excited by two electric signals with a phase difference ofπ/2,the metal track will be driven by friction ***,the design and operating principle of the tracked travelling system are presented in ***,the operating modes of the piezoelectric transducer are analyzed by FEM and compared with the vibration measurement ***,the prototype is manufactured and assembled,and the motion characteristics experiments of the system are carried out to valid the *** the voltage is 460V and the frequency is 65.2 kHz,the maximum velocity of the system can reach to51.5mm/*** results show that the tracked travelling system has a potential application in rover robots for planetary exploration.

关键词： Piezoelectric transducer Metal track Travelling system Motion characteristics

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International Journal of Plant Engineering and Management 2002年第1期7卷 45-49页

作者： YANG Jian hong 1, cheng shu 2, WANG you jun 2, CHEN Fei 2, YU Mao hong 1 1Department of Civil Engineering, Xi’an Jiaotong University, Xi’an 710049, P.R.China 2The Second Artillery Engineering College, Xi’an 710025, P.R.China Department of Civil Engineering Xi'an Jiaotong University Xi'an 710049 P.R.China The Second Artillery Engineering College Xi'an 710025 P.R.China

In reference, we measured fracture properties of raw material, weld seam and heat affected zone of high pressure vessels(HPV); in this paper, we carried out safety evaluation on the basis of the previous work and predicted the lifetime of in service vessels with flaw by use of the fracture criterion for model Ⅰ crack in fracture mechanics. This method reduced the artificial error and the ultrasonic testing operator's work burden. The experimental and theoretical bases for the defect assessment of military HPV were established.

关键词： high pressure vessel crack fracture safety and lifetime

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Visible-light-mediated photocatalysis as a new tool for catalytic asymmetric dearomatization(CADA)reactions

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Science Bulletin 2018年第13期63卷 809-811页

作者： Yuan-Zheng cheng Xiao Zhang shu-Li you State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 200032China Collaborative Innovation Center of Chemical Science and Engineering.Tianjin 300072 China

Aromatic compounds often serve as widely available and fundamental synthetic materials in polymers,paints,cosmetics,and *** development of novel transformations based on simple aromatics to access highly value-added structures is in great *** this regard,catalytic asymmetric dearomatization(CADA)reactions can convert planar aromatic compounds

关键词：反应能光催化不对称工具合成材料激活过程混合物聚合物

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Copper-Catalyzed Oxidative Dearomatization of 2-Naphthols via Etherification

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Chinese Journal of Chemistry 2019年第9期37卷 903-908页

作者： Ji-cheng Yi Zhi-Jie Wu shu-Li you State Key Laboratory of Organometallic Chemistry Center for Excellence in Molecular SynthesisShanghai Institute of Organic ChemistryChinese Academy of Sciences345 Lingling LuShanghai 200032China School of Physical Science and Technology ShanghaiTech University100 Haike RoadShanghai 201210China

Copper-catalyzed intermolecular oxidative-etherification type dearomatization reaction of 2-naphthols was *** air as the terminal oxidant,the reaction proceeded in excellent yields under mild *** addition,the reaction between two different naphthol substrates occurred smoothly.A series of multifunctionalized β-naphthalenones,important scaffold existed widely in natural products and biologically active molecules,were synthesized efficiently.

关键词： Copper-Catalyzed Oxidative Dearomatization 2-Naphthols via Etherification multifunctionalized β-naphthalenones

When AI meets sustainable 6G

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Science China(Information Sciences) 2025年第1期 4-22页

作者： Xiaohu you Yongming HUANG cheng ZHANG Jiaheng WANG Hao YIN Hequan WU National Mobile Communications Research Laboratory Southeast University Purple Mountain Laboratories Chinese Academy of Military Science China Information Communication Technologies Group

Sixth-generation(6G) networks are anticipated to achieve transformative advancements, characterized by extreme connectivity, deep integration with artificial intelligence(AI) and sensing, and airground integration. The evolution of 6G exhibits two major trends: ubiquitous intelligence and sustainability. The former aims to embed state-of-the-art AI technology into the 6G network, from the physical layers to applications, while the latter emphasizes reducing energy consumption while enhancing network performance to address environmental concerns. Despite the amazing progress in recent years, AI advancements come with substantial increases in data and computational overhead, posing critical challenges for integrating AI into sustainable 6G networks. First, high energy consumption from large datasets and heavyweight AI models contradicts6G's green goals. Second, the precise collection of large datasets, message delivery latency, and inference delays in AI models pose challenges for real-time tasks in 6G. Third, the uninterpretability and unpredictability of AI models complicate meeting the stringent requirements for controllable transmission in dynamic wireless environments. Addressing these challenges and achieving sustainable 6G with ubiquitous intelligence calls for a revolutionary design of 6G architecture and AI frameworks. To this end, this paper introduces a novel and practical methodology for green, real-time, and controllable 6G native intelligence,starting with knowledge graph(KG) analysis to extract small but critical datasets, followed by the development of distributed lightweight AI models, and the use of digital twins(DTs) to create precise replicas of physical 6G networks. This leads to a pervasive multi-level(PML)-AI framework supported by a task-centric, three-layer 6G architecture. The AI framework operates through non-real-time and real-time cycles, leveraging three key technologies: wireless data KGs for efficient data management,lightweight AI mode

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Relationship between longitudinal changes in lipid composition and ischemic stroke among hypertensive patients

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World Journal of Clinical Cases 2025年第4期13卷 18-27页

作者： cheng-cheng Wei Yu-Qing Huang cheng-Hong Yu Department of Cardiology Tongxiang First People's HospitalTongxiang 314500Zhejiang ProvinceChina Department of Cardiology Guangdong Cardiovascular InstituteGuangzhou 510080Guangdong ProvinceChina

BACKGROUND Dyslipidemia was strongly linked to stroke,however the relationship between dyslipidemia and its components and ischemic stroke remained *** To investigate the link between longitudinal changes in lipid profiles and dyslipidemia and ischemic stroke in a hypertensive *** Between 2013 and 2014,6094 hypertension individuals were included in this,and ischemic stroke cases were documented to the end of *** changes of lipid were stratified into four groups:(1)Normal was transformed into normal group;(2)Abnormal was transformed into normal group;(3)Normal was transformed into abnormal group;and(4)Abnormal was transformed into abnormal *** examine the link between longitudinal changes in dyslipidemia along with its components and the risk of ischemic stroke,we utilized multivariate Cox proportional hazards models with hazard ratio(HR)and 95%*** The average age of the participants was 62.32 years±13.00 years,with 329 women making up 54.0%of the *** the course of a mean follow-up of 4.8 years,143 ischemic strokes *** normal was transformed into normal group was used as a reference,after full adjustments,the HR for dyslipidemia and ischemic stroke among abnormal was transformed into normal group,normal was transformed into abnormal group and abnormal was transformed into abnormal Wei CC et *** changed and ischemic stroke WJCC https://*** 2 February 6,2025 Volume 13 Issue 4 group were 1.089(95%CI:0.598-1.982;P=0.779),2.369(95%CI:1.424-3.941;P<0.001)and 1.448(95%CI:1.002-2.298;P=0.047)(P for trend was 0.233),*** In individuals with hypertension,longitudinal shifts from normal to abnormal in dyslipidemia-particularly in total and low-density lipoprotein cholesterol-were significantly associated with the risk of ischemic stroke.

关键词： Longitudinal change Hypertension Dyslipidemia Lipid profile Ischemic stroke

Investigating Müller glia reprogramming in mice: a retrospective of the last decade, and a look to the future

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Neural Regeneration Research 2025年第4期20卷 946-959页

作者： Zhiyuan Yin Jiahui Kang Xuan cheng Hui Gao shujia Huo Haiwei Xu Key Lab of Visual Damage and Regeneration&Restoration of Chongqing Southwest Eye HospitalSouthwest HospitalThird Military Medical University(Army Medical University)ChongqingChina

Müller glia,as prominent glial cells within the retina,plays a significant role in maintaining retinal homeostasis in both healthy and diseased *** lower vertebrates like zebrafish,these cells assume responsibility for spontaneous retinal regeneration,wherein endogenous Müller glia undergo proliferation,transform into Müller glia-derived progenitor cells,and subsequently regenerate the entire retina with restored ***,Müller glia in the mouse and human retina exhibit limited neural reprogramming.Müller glia reprogramming is thus a promising strategy for treating neurodegenerative ocular disorders.Müller glia reprogramming in mice has been accomplished with remarkable success,through various *** in molecular,genetic,epigenetic,morphological,and physiological evaluations have made it easier to document and investigate the Müller glia programming process in ***,there remain issues that hinder improving reprogramming efficiency and ***,understanding the reprogramming mechanism is crucial toward exploring factors that will improve Müller glia reprogramming efficiency,and for developing novel Müller glia reprogramming *** review describes recent progress in relatively successful Müller glia reprogramming *** also provides a basis for developing new Müller glia reprogramming strategies in mice,including epigenetic remodeling,metabolic modulation,immune regulation,chemical small-molecules regulation,extracellular matrix remodeling,and cell-cell fusion,to achieve Müller glia reprogramming in mice.

关键词： cell fusion chemical small-molecules epigenetic extracellular matrix immune metabolic mice Müller glia neurodegenerative diseases reprogramming retina regeneration

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