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Applied Mathematics and Mechanics(English Edition) 2021年第5期42卷 721-746页

作者： A.T.TRAN h.LE QUANG Q.c.hE D.h.NGUYEN Research and Application center for Technology in civil Engineering University of Transport and CommunicationsHanoi 10000Vietnam Laboratoire Modelisation et Simulation Multi-Echelle Unite Mixte de Recherche 8208Centre National de la Recherche ScientifiqueUniversite Gustave EiffelMarne-la-Vallee F-77454France School of Mechanical Engineering Southwest Jiaotong UniversityChengdu 610031China

The present work is concerned with a two-dimensional(2D)Stokes flow through a channel bounded by two parallel solid *** distance between the walls may be arbitrary,and the surface of one of the walls can be arbitrarily *** main objective of this work consists in homogenizing the heterogeneous interface between the rough wall and fluid so as to obtain an equivalent smooth slippery fluid/solid interface characterized by an effective slip *** solve the corresponding problem,two efficient numerical approaches are elaborated on the basis of the method of fundamental solution(MFS)and the boundary element methods(BEMs).They are applied to different cases where the fluid/solid interface is periodically or randomly *** results obtained by the proposed two methods are compared with those given by the finite element method and some relevant ones reported in the *** comparison shows that the two proposed methods are particularly efficient and accurate.

关键词： effective slip length method of fundamental solution(MFS) boundary element method(BEM) Stokeslet micro-channel fluid/solid interface

Numerical Simulation of Free Surface by an Area-Preserving Level Set Method

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communications in computational Physics 2012年第4期11卷 1347-1371页

作者： Tony W.h.Sheu c.h.Yu Department of Engineering Science and Ocean Engineering National Taiwan UniversityNo.1Sec.4Roosevelt RoadTaipeiTaiwan Taida Institute of Mathematical Sciences(TIMS) National Taiwan University center for Quantum Science and Engineering(cQSE) National Taiwan University

We apply in this study an area preserving level set method to simulate gas/water interface *** the sake of accuracy,the spatial derivative terms in the equations of motion for an incompressible fluid flow are approximated by the fifthorder accurate upwinding combined compact difference(UccD)*** scheme development employs two coupled equations to calculate the first-and second-order derivative terms in the momentum *** accurately predicting the level set value,the interface tracking scheme is also developed to minimize phase error of the first-order derivative term shown in the pure advection *** the purpose of retaining the long-term accurate hamiltonian in the advection equation for the level set function,the time derivative term is discretized by the sixth-order accurate symplectic Runge-Kutta ***,to keep as a distance function for ensuring the front having a finite thickness for all time,the re-initialization equation is *** the verification of the optimized UccD scheme for the pure advection equation,two benchmark problems have been chosen to investigate in this *** level set method with excellent area conservation property proposed for capturing the interface in incompressible fluid flows is also verified by solving the dam-break,Rayleigh-Taylor instability,two-bubble rising in water,and droplet falling problems.

关键词： Level set method phase error upwinding combined compact scheme hamiltonian symplectic Runge-Kutta area conservation property

Tri-directional shaking table tests of vibration sensitive equipment with static dynamics interchangeable-ball pendulum system

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Earthquake Engineering and Engineering Vibration 2010年第1期9卷 103-112页

作者： c.S. Tsai Yung-chang Lin Wen-Shin chen h.c. Su D G epartment of civil Engineering Feng Chia University Taichung Chinese Taipei Graduate Institute of civil and hydraulic Engineering Feng Chia University Taichung Chinese Taipei Department of Water Resources Engineering and conservation Feng Chia University Taichung Chinese Taipei

Recently, the high-tech industry has become a key industry for economic development in many countries. however, vibration sensitive equipment located in these industrial buildings is vulnerable during earthquakes, which may cause huge economic loss. In this study, an innovative isolator for safeguarding the vibration sensitive equipment, namely, the static dynamics interchangeable^all pendulum system （SDI-BPS） is proposed and investigated to examine its protective capability for the vibration sensitive equipment during earthquakes through a series of tri-directional shaking table tests. The experimental results illustrate that the SDI-BPS isolator can provide significant damping to rolling types of base isolation systems for reducing the bearing displacement and size, and avoid the stress concentration, which can cause damage or scratches on the rolling surface of the isolator, to prolong its life span of service. The SDI-BPS isolator also provides excellent capability in protecting the vibration sensitive equipment and exhibits a stable behavior under long terms of service loadings and earthquakes.

关键词： ball pendulum system critical equipment base isolation vibration sensitive equipment base isolator passive control earthquake engineering structural control

Precipitation on stacking faults in Mg–9.8wt%Sn alloy

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Journal of Materials Science & Technology 2020年第10期42卷 230-240页

作者： c.Q.Liu c.he h.W.chen J.F.Nie International Joint Laboratory for Light Alloys(Ministry of Education) College of Materials Science and EngineeringChongqing UniversityChongqing400044China Department of Materials Science and Engineering Monash UniversityVictoria3800Australia Electron Microscopy center Chongqing UniversityChongqing400044PR China

In this work,we have systematically investigated precipitation ofβ’-Mg3Sn phase on intrinsic stacking faults I1 and I2 in a Mg-9.8 wt%Sn alloy using aberration-corrected scanning transmission electron *** observed I1 faults are generated by the dissociation of c+a perfect dislocations and bounded by Frank partial dislocations having a Shockley *** ofβ’on I1 involves a shear of 1/3α,similar to its formation directly from theα-Mg ***β’phase often nucleates at one end of an I1 fault due to the interaction between shear strain fields ofβ’and the Shockley component of the Frank partial at that end,and subsequently grows towards the other end of the *** theβ’reaches to the other end,the Shockley partial bounding the lengthening end of theβ’reacts with the Frank partial bounding the fault,generating an a perfect dislocation that can glide away from the precipitate and the *** observed I2 faults are generated by the dissociation of a perfect dislocations and bounded by Shockley *** ofβ’on I2 does not need a shear of 1/3α,since the pre-existing I2 fault already provides an ABcA four-layer structure ofβ’.Thickening of theβ’that has already formed on the I2 involves the successive occurrence of three crystallographically equivalent shears of 1/3αon every second(0002)αplane of theα-Mg *** this thickening mechanism is similar to that of theβ’formed directly from theα-Mg matrix,an a perfect dislocation will be produced when theβ’is thickened to eight layers,and it can again glide away from the precipitate and the fault.

关键词： heterogeneous precipitation hAADF-STEM Shockley partial dislocation Frank partial dislocation Dislocation reaction

Kartogenin induces cartilage-like tissue formation in tendon–bone junction

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Bone Research 2014年第1期2卷 61-70页

作者： Jianying Zhang James h-c Wang MechanoBiology Laboratory Departments of Orthopaedic Surgery Bioengineering Mechanical Engineering and Materials Science and Physical Medicine and Rehabilitation University of Pittsburgh

Tendon-bone junctions （TBJs） are frequently injured, especially in athletic settings. healing of TBJ injuries is slow and is often repaired with scar tissue formation that compromises normal function. This study explored the feasibility of using kartogenin （KGN）, a biocompound, to enhance the healing of injured TBJs. We first determined the effects of KGN on the proliferation and chondrogenic differentiation of rabbit bone marrow stromal cells （BMScs） and patellar tendon stern/progenitor cells （PTScs） in vitro. KGN enhanced cell proliferation in both cell types in a concentration-dependent manner and induced chondrogenic differentiation of stem cells, as demonstrated by high expression levels of chondrogenic markers aggrecan, collagen II and Sox-9. Besides, KGN induced the formation of cartilage-like tissues in cell cultures, as observed through the staining of abundant proteoglycans, collagen II and osteocalcin. When injected into intact rat patellar tendons in vivo, KGN induced cartilage-like tissue formation in the injected area. Similarly, when KGN was injected into experimentally injured rat Achilles TBJs, wound healing in the TBJs was enhanced, as evidenced by the formation of extensive cartilage-like tissues. These results suggest that KGN may be used as an effective cell-free clinical therapy to enhance the healing of injured TBJs.

关键词： bone junction BMScs

Mathematical modeling and full-scale shaking table tests for multi-curve buckling restrained braces

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Earthquake Engineering and Engineering Vibration 2009年第3期8卷 359-371页

作者： c. S. Tsai Yungchang Lin Wenshin chen h. c. Su Department of civil Engineering Feng Chia University Taichung Chinese Taipei Graduate Institute of civil and hydraulic Engineering Feng Chia University Taichung Chinese Taipei Department of Water Resources Engineering and conservation Feng Chia University Taichung Chinese Taipei

Buckling restrained braces （BRBs） have been widely applied in seismic mitigation since they were introduced in the 1970s. however, traditional BRBs have several disadvantages caused by using a steel tube to envelope the mortar to prevent the core plate from buckling, such as： complex interfaces between the materials used, uncertain precision, and time consumption during the manufacturing processes. In this study, a new device called the multi-curve buckling restrained brace （Mc-BRB） is proposed to overcome these disadvantages. The new device consists of a core plate with multiple neck portions assembled to form multiple energy dissipation segments, and the enlarged segment, lateral support elements and constraining elements to prevent the BRB from buckling. The enlarged segment located in the middle of the core plate can be welded to the lateral support and constraining elements to increase buckling resistance and to prevent them from sliding during earthquakes. component tests and a series of shaking table tests on a full-scale steel structure equipped with Mc-BRBs were carried out to investigate the behavior and capability of this new BRB design for seismic mitigation. The experimental results illustrate that the Mc-BRB possesses a stable mechanical behavior under cyclic loadings and provides good protection to structures during earthquakes. Also, a mathematical model has been developed to simulate the mechanical characteristics of BRBs.

关键词： buckling restrained brace energy absorption passive control earthquake energy plasticity model structural control multi-curve BRB

Effect of pre-deformation on microstructure and mechanical properties of WE43 magnesium alloy II: Aging at 250 and 300℃

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Journal of Magnesium and Alloys 2020年第1期8卷 103-110页

作者： Y.h.Kang Z.h.huang S.c.Wang h.Yan R.S.chen J.c.huang Guangdong-hong Kong Joint Research and Development center on Advanced Manufacturing Technology for Light Alloys Guangdong Institute of Materials and ProcessingGuangzhou 510650China Institute of Metal Research chinese Academy of Sciences Shenyang 110016China hong Kong Institute for Advanced Study Department of Materials Science and EngineeringCity University of Hong KongHong KongChina

In this work,the microstructural evolution and mechanical properties of a pre-deformed WE43 magnesium alloy when aged at 250 and 300℃ were further *** is found that the abundant deformation twins introduced by pre-deformation were maintained within the alloy during the aging *** particles formed at the twin boundaries and coarsened with aging time,especially at 300℃.When peak-aged at 250℃,the fine metastable β'''and β' precipitates formed in the un-deformed alloy have been transformed into relatively large β1 and β precipitates by the *** peak-aged at 300℃,the pre-deformation obviously refined the β *** properties indicate that pre-deformation can increase the yield strength by 19Mpa and 54Mpa for the peak-aged alloy at 250℃ and 300℃,respectively,and will not obviously deteriorate the tensile elongations.

关键词： WE43 magnesium alloy Pre-deformation Aging Microstructure Mechanical properties

Simulating canopy stomatal conductance of winter wheat and its distribution using remote sensing information

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Journal of Environmental Sciences 2001年第4期13卷 439-443页

作者： Zhang, J.-h. Fu, c.-b. Kanzawa, h. START Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China

The canopy stomatal movement, a plant physiological process, generally occurs within leaves but its influence on exchange of cO2, water vapor, and sensible heat fluxes between atmosphere and terrestrial ecosystem. Many studies have documented that the interaction between leaf photosynthesis and canopy stomatal conductance is obvious. Thus, information on stomatal conductance is valuable in climate and ecosystem models. In current study, a newly developed model was adopted to calculate canopy stomatal conductance of winter wheat in huang-huai-hai (h-h-h) Plain of china (31.5 - 42.7°N, 110.0 - 123.0°E). The remote sensing information from NOAA-AVhRR and meteorological observed data were used to estimate regional scale stomatal conductance distribution. canopy stomatal conductance distribution pattern of winter wheat on March 18, 1997 was also presented. The developed canopy stomatal conductance model might be used to estimate canopy stomatal conductance in land surface schemes and seems can be acted as a boundary condition in regional climatic model runs.

关键词： carbon dioxide Data reduction Ecosystems heat flux Meteorology Photosynthesis Physiology Plants (botany) Remote sensing Vapors

SOME OBSERVATIONS ON DYNAMIc PROPERTIES OF REcEPTIVE FIELD ORGANIZATION OF cOMPLEX cELLS IN cAT VISUAL cORTEX

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Science china chemistry 1987年第1期30卷 44-54页

作者：李朝义,h.c.NOThDURFT Shanghai Institute of Physiology Academia Sinica Max-Planck-Institute for Biophysical chemistry Goettingen West Germany

The dynamic properties of discharge fields (DFs) of the complex cells in areas 17 and 18 of cat'sbrain were observed. The sequence of activation for different areas in the DF indicated a concentric ar-rangement of latency distribution. The DE organization was proved to be dependent closely cn velocityof stimulus movement. Twin-or triple-DFs were found for some cells, each responded selectively to oneof the opposite directions of movement.

关键词： SOME OBSERVATIONS ON DYNAMIc PROPERTIES OF REcEPTIVE FIELD ORGANIZATION OF cOMPLEX cELLS IN cAT VISUAL cORTEX DDF

Functional gastrointestinal disorders in inflammatory bowel disease: Time for a paradigm shift?

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World Journal of Gastroenterology 2020年第26期26卷 3712-3719页

作者： Dipesh h Vasant Alexander c Ford Gastroenterology Manchester University NHS Foundation TrustWythenshawe HospitalManchester M239LTUnited Kingdom Division of Diabetes Endocrinology and GastroenterologyUniversity of ManchesterManchester M239LTUnited Kingdom Leeds Institute of Medical Research at St.James’s University of LeedsLeeds LS97TFUnited Kingdom Leeds Gastroenterology Institute Leeds Teaching Hospitals NHS TrustLeeds LS97TFUnited Kingdom

Recent advances in biological therapies have revolutionalised and redefined treatment targets in inflammatory bowel disease(IBD).There is now a stronger emphasis on achieving the more stringent therapeutic goals of mucosal and histological healing,rather than clinical remission ***,the treatment of refractory“functional”gastrointestinal symptoms,often attributed as the aftermath of previous inflammation,has recently become more prominent in quiescent *** further expected advances in anti-inflammatory treatments on the horizon,the burden of such symptoms in quiescent disease,which have been relatively neglected,is set to become an even bigger *** this article,we highlight the current state of research and understanding in this field,including recent developments and clinical practice guidelines on the diagnosis and management of functional gastrointestinal symptoms,such as irritable bowel syndrome and functional anorectal and pelvic floor disorders,in patients with quiescent *** disorders are not only highly prevalent in these patients,they are often misdiagnosed,and are difficult to treat,with very few evidence-based ***,they are associated with substantial impairment in quality-of-life,considerable morbidity,and psychological *** is therefore an urgent need for a change in emphasis towards earlier recognition,positive diagnosis,and targeted treatment for patients with ongoing functional gastrointestinal symptoms in the absence of active *** article also highlights the need for further research to develop much needed evidence-based therapies.

关键词： Irritable bowel syndrome Inflammatory bowel disease Functional gastrointestinal disorders Faecal incontinence Pelvic floor dyssynergia