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Journal of Hydrodynamics 2022年第3期34卷 444-450页

作者： Yun Long Han-qiao Han Bin Ji Xin-ping Long Wuhan Second Ship design and Research Institute Wuhan430064China State Key laboratory of Water Resources and Hydropower Engineering Science Wuhan UniversityWuhan430072China School of Power and Mechanical Engineering Wuhan UniversityWuhan430072China

In this study,the delayed detached eddy simulation(DDES)is coupled with a homogenous cavitation model to simulate the cavitating turbulent flow around a propeller behind a full body ship with special emphasis on the influence of the vortex generator(VG)on the propeller cavitation and the hull pressure *** small calculation uncertainty as evaluated by the DDES verification and validation(V&V)method indicates that the present simulation can accurately reproduce the propeller performance and cavitation,and the predicted hull pressure fluctuation is in a fairly good agreement with the available experimental *** mechanism is explored through the current numerical results how the VG affects the local velocity distribution,along with the influences of the VG on the propeller cavitation and the hull pressure *** is shown that the streamwise vortex is induced by the VG near the hull boundary *** very low velocity region in the hull wake is reduced due to the effect of the streamwise ***,the propeller cavitation develops more mildly and the hull pressure fluctuation decreases due to the influence of the VG.

关键词： Propeller cavitation delayed detached eddy simulation(DDES) vortex generator(VG) streamwise vortex

Effects of different biochars on antibiotic resistance genes during swine manure thermophilic composting

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International Journal of Agricultural and Biological Engineering 2018年第6期11卷 166-171页

作者： Jian Wang Bin Sui Yujun Shen Haibo Meng Lixin Zhao Haibin Zhou Ran Li Jingtao Ding Hongsheng Cheng Xi Zhang Institute of Energy and Environmental Protection Chinese Academy of Agricultural Engineering Planning and DesignBeijing 100125China Key laboratory of Technologies and Models for Cyclic Utilization from Agricultural Resources Ministry of Agriculture and Rural Affairs of the People's Republic of ChinaBeijing 100125China Chinese Academy of Agricultural Engineering Planning and design Beijing 100125China

Elimination of antibiotic resistance genes(ARGs)in animal manure from concentrated animal feeding operations by thermophilic composting has drawn increasing *** study investigated the effects of sawdust biochar,corn stover biochar and peanut hull biochar with three spiked levels on ARGs in swine manure during thermophilic *** ARGs corresponding to four classes of antibiotics(tetracyclines,sulfonamides,macrolides and quinolones)were determined in the composting *** indicated that the ten tested composting groups became fully mature after 30-day thermophilic composting ***,tetO and ermB were reduced in all tested groups;tetC and tetG,tetX,sul1,sul2,ermF,qnrD and aac(6’)-Ib were mostly reduced under low level biochar addition but increased under higher level biochar addition;gyrA increased under medium biochar addition and reduced in other groups;oqxB remained comparatively stable throughout the composting *** addition levels of spiked biochar are more important than types of spiked biochar on the removal of ARGs in the composting *** average removal rates of ARGs in the control group,low,medium and high level biochar addition groups were 0.24 logs,0.52-0.72 logs,-0.52-0.18 logs and-0.19-0.21 logs,*** summary,low level biochar addition could enhance the elimination of studied ARGs in swine manure during the composting process,while medium level biochar addition to the composting piles would increase the risk of ARGs’propagation.

关键词： biochar antibiotic resistance genes thermophilic composting swine manure

Towards additive manufacturing oriented geometric modeling using implicit functions

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Visual Computing for Industry,Biomedicine,and Art 2018年第1期1卷 95-110页

作者： Qingde Li Qingqi Hong Quan Qi Xinhui Ma Xie Han Jie Tian School of Engineering and Computer Science University of HullHull HU67RXUK Software School Xiamen UniversityXiamenChina School of Computer Science and Control Engineering North University of ChinaTaiyuanChina Intelligent Bioinformatics Systems Division Institute of AutomationThe Chinese Academy of SciencesBeijingChina

Surface-based geometric modeling has many advantages in terms of visualization and traditional subtractive manufacturing using computer-numerical-control cutting-machine ***,it is not an ideal solution for additive manufacturing because to digitally print a surface-represented geometric object using a certain additive manufacturing technology,the object has to be converted into a solid ***,converting a known surface-based geometric representation into a printable representation is essentially a redesign process,and this is especially the case,when its interior material structure needs to be *** specify a 3D geometric object that is ready to be digitally manufactured,its representation has to be in a certain volumetric *** this research,we show how some of the difficulties experienced in additive manufacturing can be easily solved by using implicitly represented geometric *** surface-based geometric representation is subtractive manufacturing-friendly,implicitly described geometric objects are additive manufacturing-friendly:implicit shapes are 3D printing *** implicit geometric representation allows to combine a geometric shape,material colors,an interior material structure,and other required attributes in one single description as a set of implicit functions,and no conversion is *** addition,as implicit objects are typically specified procedurally,very little data is used in their specifications,which makes them particularly useful for design and visualization with modern cloud-based mobile devices,which usually do not have very big storage ***,implicit modeling is a design procedure that is parallel computing-friendly,as the design of a complex geometric object can be divided into a set of simple shape-designing tasks,owing to the availability of shape-preserving implicit blending operations.

关键词： Additive manufacturing 3D printing-friendly CAD Implicit function Isosurface Level-set Function-based shape modeling Implicit modeling

Full time-domain nonlinear coupled dynamic analysis of a truss spar and its mooring/riser system in irregular wave

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Science China(Physics,Mechanics & Astronomy) 2014年第1期57卷 152-165页

作者： YANG MinDong TENG Bin XIAO LongFei NING DeZhi SHI ZhongMin QU Yan Guangdong Electric Power design Institute China Energy Engineering Group Co. Ltd. Department of Ocean Engineering Ocean University of China State Key laboratory of Coastal and Offshore Engineering Dalian University of Technology State Key laboratory of Ocean Engineering Shanghai Jiao Tong University Technology Research Department China National Offshore Oil Corporation

A new full time-domain nonlinear coupled method has been established and then applied to predict the responses of a Truss Spar in irregular wave. For the coupled analysis, a second-order time-domain approach is developed to calculate the wave forces, and a finite element model based on rod theory is established in three dimensions in a global coordinate system. In nu- merical implementation, the higher-order boundary element method （HOBEM） is employed to solve the velocity potential, and the 4th-order Adams-Bashforth-Moultn scheme is used to update the second-order wave surface. In deriving convergent solu- tions, the hull displacements and mooring tensions are kept consistent at the fairlead and the motion equations of platform and mooring-lines/risers are solved simultaneously using Newmark-fl integration scheme including Newton-Raphson iteration. Both the coupled quasi-static analysis and the coupled dynamic analysis are performed. The numerical simulation results are also compared with the model test results, and they coincide very well as a whole. The slow-drift responses can be clearly ob- served in the time histories of displacements and mooring tensions. Some important characteristics of the coupled responses are concluded.

关键词： coupled method full time-domain second-order truss spar rod theory irregular wave

Data-driven discovery of 2D materials by deep generative models

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npj Computational Materials 2022年第1期8卷 2218-2225页

作者： Peder Lyngby Kristian Sommer Thygesen Computational Atomic-scale Materials design(CAMD) Department of PhysicsTechnical University of Denmark2800Kgs.LyngbyDenmark

Efficient algorithms to generate candidate crystal structures with good stability properties can play a key role in data-driven materials ***,we show that a crystal diffusion variational autoencoder(CDVAE)is capable of generating two-dimensional(2D)materials of high chemical and structural diversity and formation energies mirroring the training ***,we train the CDVAE on 26152D materials with energy above the convex hullΔH_(hull)hull)hull and could potentially be *** relaxed atomic structures of all the materials are available in the open Computational 2D Materials Database(C2DB).Our work establishes the CDVAE as an efficient and reliable crystal generation machine,and significantly expands the space of 2D materials.

关键词： crystal convex stability

NUMERICAL SIMULATION OF TRANSIENT FLOW AROUND A SHIP IN UNSTEADY BERTHING MOTION

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Journal of Hydrodynamics 2009年第3期21卷 379-385页

作者： WANG Hua-ming ZOU Zao-jian TIAN Xi-min School of Naval Architecture Ocean and Civil Engineering Shanghai Jiao Tong University Shanghai 200240 China School of Naval Architecture Ocean and Civil Engineering Shanghai Jiao Tong University Shanghai 200240 State Key laboratory of Ocean Engineering Shanghai Jiao Tong University Shanghai 200030 China Marine design and Research Institute of China Shanghai 200011 China

Ship berthing is a specific maneuver operation. The flow around a berthing ship and the forces acting on the hull are quite different from those for a ship in normal navigation. By solving the unsteady Reynolds-Averaged Navier-Stokes （RANS） equations, the transient flow field around a ship undergoing unsteady lateral motion is simulated and the varying lateral hydrodynamic force acting on the hull is evaluated in this article. The numerical results obtained with different turbulence models are analyzed and compared with experimental results and other numerical results published in literature, and a turbulence model more suitable for simulation of the viscous flow around a ship undergoing unsteady berthing is determined.

关键词： ship berthing transient flow lateral hydrodynamic force numerical simulation

Optimal design and Mechanical Simulation of Rubber bushing with Convex hull Structure Based on Bionics

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Journal of Bionic Engineering 2023年第5期20卷 2018-2029页

作者： Ce Liang Min Li Jicai Liang Shaoqiang Wang Qigang Han Yi Li Key laboratory of Automobile Materials Ministry of Educationand College of Materials Science and EngineeringJilin UniversityChangchun130025China Roll Forging Research Institute Jilin UniversityChangchun130025China School of Computer Science and Technology Changchun UniversityChangchun130022China

Inspired by the safe landing of cats falling from high altitudes,a bionic flexible rubber bushing structure is proposed and its motion characteristics are systematically studied to explore its potential application in the suppression of *** convex hull structure on the bushing surface is abstracted from the cat’s claw pad,and the hyper-viscoelastic model is selected as the constitutive model of the rubber *** addition,the design with the best vibration damping effect is finally obtained by reasonably adjusting the amount of radial compression and distribution of bionic ***,under the same conditions,the test results of the dynamic characteristics of the bushing verify the accuracy of the simulation *** results show that the convex hull bionic structure designed in this paper can effectively change the motion characteristics of the rubber bushing under various working conditions,which provides new inspiration or potential possibility for the design of rubber bushing in the future.

关键词： Rubber bushing Bionic design Finite element analysis Vibration isolator Radial compression

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PPP项目VFM评价流程与其动态监管方式

管理评论 2018年第10期30卷 270-278页

作者：张紫薇英国hull大学商学、法学及政治学院英国Hull LN5 8EN

尽管PPP项目即政府和社会资本合作模式项目在我国已经取得了显著的成果,但在VFM评价程序与方法、政府监管程序与方法上仍然有很多问题有待于进一步深入研究。本文分析了国际PPP项目的做法与经验,讨论了VFM评价的基本原理与方法,提出了基... 详细信息

尽管PPP项目即政府和社会资本合作模式项目在我国已经取得了显著的成果,但在VFM评价程序与方法、政府监管程序与方法上仍然有很多问题有待于进一步深入研究。本文分析了国际PPP项目的做法与经验,讨论了VFM评价的基本原理与方法,提出了基于PPP项目概念设计的PPP项目全寿命周期VFM评价流程;提出了项目动态监管的基本原理与方法。其研究成果将为我国PPP项目的实施提供有益的帮助。

关键词： PPP项目项目决策项目采购 VFM评价流程动态监管原理

REVIEW OF HIGH LEVEL FAULT MODELING APPROACHES FOR MIXED-SIGNAL SYSTEMS

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Journal of Electronics(China) 2010年第4期27卷 490-497页

作者： Xia Likun Ian Bell Antony Wilkinson Department of Electrical ＆ Electronic Engineering Universiti Teknologi Petronas 31750 Tronoh Perak Malaysia Department of Engineering Hull University Cottingham Road United Kingdom HU57RX

In the modern analogue design, Transistor Level Fault Simulation (TLFS) plays the im-portant part since every fault in the whole circuit has to be simulated at that level. Unfortunately, it is a very CPU intensive task even though it maintains the high accuracy. Therefore, High Level Fault Modeling (HLFM) and High Level Fault Simulation (HLFS) are required in order to alleviate the efforts of simulation. In this paper, different HLFM approaches are reviewed at the device level during last two decades. We clarify their domains of application and evaluate their strengths and current limitations. We also analyze causes of faults and introduce various test approaches.

关键词： High Level Fault Modeling (HLFM) Automated Model Generation (AMG)

Toward an Optimum design of an Amorphous Silicon Photovoltaic/Thermal System:Simulation and Experiments

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Journal of Thermal Science 2023年第3期32卷 947-964页

作者： REN Xiao LI Jing LIU Weixin ZHU Chuanyong PEI Gang GONG Liang College of New Energy China University of Petroleum(East China)Qingdao 266580China Research Center for Sustainable Energy Technologies Energy and Environment InstituteUniversity of HullHU67RXUK Department of Thermal Science and Energy Engineering University of Science and Technology of ChinaHefei 230026China

Amorphous silicon photovoltaic/thermal(a-Si-PV/T)technology is promising due to the low power temperature coefficient,thin-film property,thermal annealing effect of the solar cells,and high conversion efficiency in *** design of a-Si-PV/T system is influenced by a number of thermodynamic,structural,and external *** analysis is useful for a good design of the system.A dynamic distributed parameter model is built and verified in this *** tests are carried *** impacts of operating temperature,mass flow rate,cover ratio of solar cells,heat transfer area,and frame shadow ratio on its performance are theoretically and experimentally *** results indicate that seven or eight copper tubes are suitable to achieve a high overall efficiency of the a-Si-PV/T *** frame and tilt angle shall avoid a shadow ratio of more than 8.3%during *** difference between power outputs at operating temperatures of 35℃and55℃in the first month is about 0.21%while it drops to less than 0.1%in the twelfth *** with conventional PVT systems,the a-Si-PV/T system benefits from a higher design temperature with a minor efficiency decrement.

关键词： amorphous silicon cell photovoltaic thermal system parametric analysis distributed parameter model frame shadow