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A　HYBrID　METHOD　FOr　THE　SIMULATION　OF　WAVE　SpECTrUM　TrANSFOrMATION　AND　BrEAKING　pHENOMENA　ON　A　SLOpE

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Journal of Hydrodynamics 1995年第2期7卷 76-83页

作者： Li Yu-cheng Dong Guo-hai(department of {2. engineering dalian university of technology,dalian 1.602., p. r. china) dalian Univ of technology Dalian China

In shallow water, during the wave propagation the nonlinear and wave breaking effect must be taken into account. In this peper a simplified hybrid method was proposed, in which a combined frequency and time domain analysis was used. By using authors' method, the process are quite simple and easy to run on a pC computer, but the nonlinear and wave bleaking effect was still been considered. The computed data coincide authors' test results quite well.

关键词： wave tranformation wave breaking numerical simulstion

NUMErICAL ANALYSIS OF SIDE DISCHArGES INTO A CHANNEL FLOW USING AN rNG k^(-ε)MODEL

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Journal of Hydrodynamics 1999年第3期11卷 44-54页

作者： Wang Xiao jian cheng Liang Deparment of civil {2., The university of Western Australia, Nedlands 6907, Western Australia Cui Li department of civil {2., dalian university of technology, dalian 1.602., p.r.china (received Sep.

Side discharge into a channel flow is numerically simulated using an rNG based k ε turbulence model. It is shown that the results of the recirculation zone obtained using the rNG k ε model generally agree better with the experimental results compared with those by the standard k ε model. The reason for the improvement of the results obtained using the rNG k ε model over those by the standard k ε model on this flow is analyzed. The flow at small discharge ratios is thoroughly investigated and it is found that the velocity profile at the jet exit is extremely non uniform at small discharge ratios. It is also found that the degree of the non uniformity decreases as the discharge ratio increases, and is very slight for discharge ratios larger than 2.0. The effects of calculation domain, mesh size, wall functions, bed roughness and discharge ratios on the size of separation zone are also investigated in detail.

关键词： rNG kε model side discharge flow separation zone bed roughness

Modelling of multi-bodies in close proximity under water waves——Fluid resonance in narrow gaps

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Science china(physics,Mechanics & Astronomy) 2011年第1期54卷 16-25页

作者： LU Lin1,2,TENG Bin3,cheng Liang 4,SUN Liang5 & CHEN XiaoBo6 1 Center for Deepwater engineering,dalian university of technology,dalian 1.602.,china 2 State Key Laboratory of Structural Analysis for Industrial Equipment,dalian university of technology,dalian 1.602.,china 3 State Key Laboratory of Coastal and Offshore engineering,dalian university of technology,dalian 1.602.,china 4 School of civil and resource engineering,The university of Western Australia,Crawly 6003,Australia 5 Centre for Offshore research and engineering,department of civil engineering,National university of Singapore,117576,Singapore 6 research department,Bureau Veritas,Neuilly-Sur-Seine,92570,France 1. Center for Deepwater engineering Dalian University of Technology Dalian 116024 China2. State Key Laboratory of Structural Analysis for Industrial Equipment Dalian University of Technology Dalian 116024 China3. State Key Laboratory of Coastal and Offshore Engineering Dalian University of Technology Dalian 116024 China4. School of Civil and Resource Engineering The University of Western Australia Crawly 6003 Australia5. Centre for Offshore Research and Engineering Department of Civil Engineering National University of Singapore Singapore 117576 Singapore6. Research Department Bureau Veritas Neuilly-Sur-Seine 92570 France

Viscous fluid model and potential flow model with and without artificial damping force(f=-μV,μ the damping coefficient and V the local averaging flow velocity) are employed in this work to investigate the phenomenon of fluid resonance in narrow gaps between multi-bodies in close proximity under water *** numerical results are compared with experimental data available in the *** comparison demonstrates that both the viscous fluid model and the potential flow model are able to predict the resonant frequency reasonably *** the conventional potential flow model(without artificial damping term) significantly over-predicts the wave height in narrow gaps around the resonant *** order to calibrate the appropriate damping coefficient used for the potential model and make it work as well as the viscous fluid model in predicting the resonant wave height in narrow gaps but with little computational efforts,the dependence of damping coefficient μ on the body geometric dimensions is examined considering the parameters of gap width Bg,body draft D,body breadth ratio Br and body number n(n = 2.3),where Br = BB/BA for the case of two bodies(Body A and Body B) with different breadths of BA and BB,*** was confirmed that the damping coefficient used for the potential flow model is not sensitive to the geometric dimensions and spatial *** was found that μ∈ [0.4,0.5] may guarantee the variation of Hg/H0 with kh to be generally in good agreement with the experimental data and the results of viscous fluid model,where Hg is the excited wave height in narrow gaps under various dimensionless incident wave frequencies kh,H0 is the incident wave height,k = 2./L is the wave number and h is the water depth.

关键词： narrow gap fluid resonance water wave viscous fluid model potential flow model finite element method boundary element method

Draft effect on wave action with a semi-infinite elastic plate

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Acta Oceanologica Sinica 2006年第6期25卷 116-127页

作者： TENG Bin 1* , GOU Ying1, cheng Liang2. LIU Shuxue1 1.State Key Laboratory of Coastal and Offshore engineering,{2., dalian 1.602., china 2.department of civil and resource engineering, university of Western Australia, Nedlands, WA 6009, Australia State Key Laboratory of Coastal and Offshore engineering Dalian University of Technology Dalian 116024 China

A method for analyzing reflection and transmission of ocean waves from a semi-infinite elastic plate with a draft is developed. The relation of energy conservation for plates with three different edge conditions (free, simply supported and built-in) is also derived. It is found that the present method satisfies the energy relation very well. The effects of draft on wave reflection and transmission coefficients as well as on the vertical vibration of the plates are examined through numerical tests. It is demonstrated that the zero draft assumption works well for low wave frequencies, but the effect of plate draft becomes significant for high wave frequencies.

关键词： elastic plate draft water waves interaction reflection transmission

Boundary element-free method for elastodynamics

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Science china(physics,Mechanics & Astronomy) 2005年第6期48卷 641-657页

作者： cheng Yumin1 & pENG Miaojuan2.1. Shanghai Institute of Applied Mathematics and Mechanics, Shanghai university, Shanghai 2.0072. {2. 2. department of civil engineering, Shanghai university, Shanghai 2.0072. {2. 1. Shanghai Institute of Applied Mathematics and Mechanics Shanghai University 200072 Shanghai China 2. department of civil {2. Shanghai University 200072 Shanghai China

The moving least-square approximation is discussed first. Sometimes the method can form an ill-conditioned equation system, and thus the solution cannot be obtained correctly. A Hilbert space is presented on which an orthogonal function system mixed a weight function is defined. Next the improved moving least-square approximation is discussed in detail. The improved method has higher computational efficiency and precision than the old method, and cannot form an ill-conditioned equation system. A boundary element-free method (BEFM) for elastodynamics problems is presented by combining the boundary integral equation method for elastodynamics and the improved moving least-square approximation. The boundary element-free method is a meshless method of boundary integral equation and is a direct numerical method compared with others, in which the basic unknowns are the real solutions of the nodal variables and the boundary conditions can be applied easily. The boundary element-free method has a higher computational efficiency and precision. In addition, the numerical procedure of the boundary element-free method for elastodynamics problems is presented in this paper. Finally, some numerical examples are given.

关键词： moving least-square approximation, improved moving least-square approximation, elastodynamics, boundary integral equation, meshless method, boundary element-free method, Fourier eigen transform.

Impact of microplastics and nanoplastics on liver health:Current understanding and future research directions

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World Journal of Gastroenterology 2024年第9期30卷 1011-1017页

作者： chun-cheng Chiang Hsuan Yeh ruei-Feng Shiu Wei-chun Chin Tzung-Hai Yen School of Medicine University of PittsburghPittsburghPA 15213United States pittsburgh Liver research Center University of PittsburghPittsburghPA 15213United States Division of Experimental pathology Department of PathologyUniversity of PittsburghPittsburghPA 15213United States Division of Endocrinology Department of PediatricsUniversity of PittsburghPittsburghPA 15213United States Center of Excellence for The Oceans National Taiwan Ocean UniversityKeelung 20224Taiwan Institute of Marine Environment and Ecology National Taiwan Ocean UniversityKeelung 20224TaiwanChina department of Materials Science and engineering University of California MercedMercedCA 95343United States department of Nephrology Clinical Poison CenterChang Gung Memorial HospitalTaoyuan 333TaiwanChina College of Medicine Chang Gung UniversityTaoyuan 333TaiwanChina

With continuous population and economic growth in the 2.st century,plastic pollution is a major global ***,the health concern of microplastics/nanoplastics(Mps/Nps)decomposed from plastic wastes has drawn public attention only in the recent *** article summarizes recent works dedicated to understanding the impact of Mps/Nps on the liver-the largest digestive organ,which is one of the primary routes that Mps/Nps enter human *** interrelated mechanisms including oxidative stress,hepatocyte energy re-distribution,cell death and autophagy,as well as immune responses and inflammation,were also *** addition,the disturbance of microbiome and gut-liver axis,and the association with clinical diseases such as metabolic dysfunction-associated fatty liver disease,steatohepatitis,liver fibrosis,and cirrhosis were briefly ***,we discussed potential directions in regard to this trending topic,highlighted current challenges in research,and proposed possible solutions.

关键词： Microplastics Nanoplastics Liver reactive oxidative species Cell death Autophagy Innate immunity Metabolic dysfunction-associated fatty liver disease Gut-liver axis

Synthesis of vertically aligned carbon nanotube arrays on silicon substrates

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Science china(Technological Sciences) 2004年第5期47卷 616-624页

作者： ZHENG ruiting1, cheng Guoan1, pENG Yibin1, 2. ZHAO Yong1, 3, LIU Huaping1 & LIANG Changlin1 1. Key Laboratory of radiation Beam technology and Materials Modification of Ministry of Education, {2. of Materials Science and engineering, Beijing Normal university, Beijing 100875, china 2. School of Science, civil Aviation university of china, Tianjin 300300, china 3. {2. of physics, Nanchang university, Nanchang 330047, china Correspondence should be addressed to Zheng ruiting 1. Key Laboratory of radiation Beam technology and Materials Modification of Ministry of Education Department of Materials Science and Engineering Beijing Normal University 100875 Beijing China 2. School of Science Civil Aviation University of China 300300 Tianjin China 3. department of physics Nanchang University 330047 Nanchang China

The growth of well-aligned carbon nanotube (CNT) arrays using a heat chemical vapor deposition system on silicon substrates is reported. The growth properties of CNT arrays are studied as a function of synthesis conditions. It is found that 750°C and 10 nm Fe film are suitable conditions for the growth of well-aligned CNT arrays. CNT arrays with a uniform diameter, thick tube wall and firm cohesion to the Si substrate can be grown for C2.2.concentration of 2.%. Based on the experiment, the processes of improving the alignment of CNT arrays and cohesion between CNT arrays and Si substrates are discussed.

关键词： carbon nanotubes, vertically aligned, silicon substrate, chemical vapor deposition.

properties of Concrete Incorporating Bed Ash from Circulating Fluidized Bed Combustion and Ground Granulates Blast-furnace Slag

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Journal of Wuhan university of technology(Materials Science) 2011年第2期26卷 348-354页

作者：鄭安 department of civil {2. National Ilan UniversityIlan 26046TaiwanChina

The properties of concrete incorporating circulating fluidized bed combustion （CFBC） bed ash and ground granulates blast-furnace slag （GGBS） were *** strength,drying shrinkage,mercury intrusion porosimetry （MIp）,scanning electronic microscopy （SEM）,and X-ray diffraction （XrD） of concrete samples containing CFBC bed ash and GGBS were *** work used initial surface absorption test （ISAT） and rapid chloride penetration test （rCpT） on concrete to measure the absorption and the ability of concrete to resist chloride ion characteristics for different concrete samples containing CFBC bed ash and *** circuit potential （OCp）,direct current polarization resistance were obtained to evaluate rebar *** CFBC bed ash was X-ray amorphous and consist of SiO2.Al2.3 and CaO *** the replacement of CFBC for sand increases,the rate of initial surface absorption （ISA） increases but compressive strength *** the content of CFBC bed ash replacement for sand maintains constant,the replacement of GGBS for cement increases,compressive strength increases but the rate of ISA *** and corrosion resistance of rebar significantly improve by utilizing a proper amount of CFBC bed ash and GGBS in concrete.

关键词： corrosion absorption chloride circulating fluidized bed combustion GGBS

Mechanical and damping performances of TpMS lattice metamaterials fabricated by laser powder bed fusion

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china Foundry 2024年第4期21卷 327-333页

作者： Yan-peng Wei Huai-qian Li Jing-jing Han Ying-chun Ma Hao-ran Zhou Jing-chang cheng Jian Shi Zhi-quan Miao Bo Yu Feng Lin National Key Laboratory of Advanced Casting Technologies Shenyang Research Institute of Foundry Co.Ltd.CAMShenyang 110022China department of Mechanical engineering Tsinghua UniversityBeijing 100084China Key Laboratory of Space physics Beijing 100076China

Lattice metamaterials based on three-period minimum surface(TpMS)are an effective means to achieve lightweight and high-strength materials which are widely used in various fields such as aerospace and ***,its vibration and noise reduction,and damping properties have not been fully ***,in this study,the TpMS structures with parameterization were designed by the method of surface migration,and the TpMS structures with high forming quality was manufactured by laser powder bed fusion(LpBF).The mechanical properties and energy absorption characteristics of the beam and TpMS structures were studied and compared by quasi-static *** modal shapes of the beam lattice structures and TpMS structures were obtained by the free modal analysis,and the damping properties of two structures were obtained by modal *** the two structures after heat treatment with the same porosity of 70%,the yield strength of the beam lattice structure reaches 40.76 Mpa,elastic modulus is 2..38 Gpa,the energy absorption value is 32.2. MJ·m^(-3),the damping ratio is 0.52..The yield strength,elastic modulus,energy absorption value,and damping ratio of the TpMS structure are 50.74 Mpa,2..37 Gpa,47.34 MJ·m^(-3),and 0.99%,*** results show that TpMS structures exhibit more excellent mechanical properties and energy absorption,better damping performance,and obvious advantages in structural load and vibration and noise reduction compared with the beam lattice structures under the same porosity.

关键词： lattice metamaterials TpMS energy absorption damping laser powder bed fusion