检索结果-南通市图书馆

Adaptive partitioning-based discrete unified gas kinetic scheme for flows in all flow regimes

Advances in Aerodynamics 2023年第1期5卷 282-311页

作者： l.M.Yang l.C.Han H.Ding Z.H.li C.Shu Y.Y.liu Department of Aerodynamics College of Aerospace EngineeringNanjing University of Aeronautics and AstronauticsNanjing 210016China State Key laboratory of Mechanics and Control of Mechanical Structures Nanjing University of Aeronautics and AstronauticsNanjing 210016China Key laboratory of Unsteady Aerodynamics and Flow Control Ministry of Industry and Information TechnologyNanjing University of Aeronautics and AstronauticsNanjing 210016China Department of Modern Mechanics University of Science and Technology of ChinaHefei 230027China National laboratory for Computational Fluid Dynamics Beihang UniversityBeijing 100191China Department of Mechanical Engineering National University of SingaporeSingapore 117576Singapore

To improve the efficiency of the discrete unified gas kinetic scheme(DUGKS)in capturing cross-scale flow physics,an adaptive partitioning-based discrete unified gas kinetic scheme(ADUGKS)is developed in this *** ADUGKS is designed from the discrete characteristic solution to the Boltzmann-BGK equation,which contains the initial distribution function and the local equilibrium *** initial distribution function contributes to the calculation of free streaming fluxes and the local equilibrium state contributes to the calculation of equilibrium *** the contribution of the initial distribution function is negative,the local flow field can be regarded as the continuous flow and the Navier-Stokes(N-S)equations can be used to obtain the solution ***,the discrete distribution functions should be updated by the Boltzmann equation to capture the rarefaction *** this,in the ADUGKS,the computational domain is divided into the DUGKS cell and the N-S cell based on the contribu-tion of the initial distribution function to the calculation of free streaming *** the N-S cell,the local flow field is evolved by solving the N-S equations,while in the DUGKS cell,both the discrete velocity Boltzmann equation and the correspond-ing macroscopic governing equations are solved by a modified *** more and more cells turn into the N-S cell with the decrease of the Knudsen number,a significant acceleration can be achieved for the ADUGKS in the continuum flow regime as compared with the DUGKS.

关键词： Boltzmann-BGK equation Discrete unified gas kinetic scheme Adaptive partitioning Discrete characteristic solution All flow regimes

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Comparative Study of Faculty Evaluation of Teaching Practice between Chinese and *** of Higher Education

引用

Frontiers of Education in China 2011年第2期6卷 200-226页

作者： Qianyi CHEN John l.YEAGER Office of Admissions and Financial Aid University of PittsburghPittsburghPA 15260USA School of Education University of PittsburghPittsburghPA 15260USA

Along with the“massification”of higher education in China since the late 1990s,the issue of quality and excellence appeared at the top of China's higher education *** faculty evaluation of teaching is one of the major approaches adopted by China's higher education sector to pursue quality and excellence,it is valuable to examine the effectiveness of faculty evaluation of teaching practices adopted by the Chinese higher education institutions(HEIs).Study of current literature reveals some similarities and differences between the faculty evaluation of teaching policies and practices between Chinese and American higher education *** paper examines the specific practices adopted by some top-tier Chinese HEIs and American elite colleges and universities,summarizes and analyzes the major differences and similarities of faculty evaluation of teaching practices between these two countries'top-tier HEIs,and discusses the applicability of the American models to the Chinese setting of higher ***,a set of best practices regarding faculty evaluation of teaching are proposed for Chinese HEIs.

关键词： faculty evaluateon of teaching Project 985 universities student ratings peer evaluation self-evaluation

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Aboveground biomass and net primary production of semi-evergreen tropical forest of Manipur, north-eastern India

引用

Journal of Forestry Research 2009年第A2期20卷 151-155,I0003页

作者： l. Supriya Devi, P.S Yadava Department of life Sciences Manipur University Imphal - 795003 Manipur India

The aboveground biomass dynamics and net primary productivity were investigated to assess the productive potential of Diptero- carpus forest in Manipur, Northeast India. Two forest stands （stand Ⅰ and Ⅱ） were earmarked randomly in the study site for the evaluation of biomass in the different girth classes of tree species by harvest method. The total biomass was 22.50 ***^-1 and 18.27 ***^-1 in forest stand I and II respectively. Annual aboveground net primary production varied from 8.86 to 10.43 ***^-1 respectively in two forest stands （stand Ⅰ and Ⅱ）. In the present study, the values of production efficiency and the biomass accumulation ratio indicate that the forest is at succession stage with high productive potential.

关键词： biomass net primary production accumulation production efficiency

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Experimental study of friction dissipators for seismic protection of building structures

引用

Earthquake Engineering and Engineering Vibration 2011年第4期10卷 475-486页

作者： F. lópez-Almansa S.T. de la Cruz C. Taylor Technical University of Catalonia Architecture Structures Department Universidad Autónoma de Ciudad Juárez Civil and Environmental Engineering Department Civil Engineering Department University of Bristol

This paper presents the results from unidirectional shaking table tests of two reduced scale steel models of a building frame, with one and two floors, respectively. These frames incorporate friction dissipators at every floor. The inputs are sine-dwells and artificial and registered earthquakes. This study is part of a larger research project aiming to assess the seismic efficiency of friction dissipators by means of an integrated numerical and experimental approach. Inside this framework, the main objectives of these experiments are to：（i） collect a wide range of results to calibrate a numerical model derived within the project, （ii） clarify some of the most controversial issues about friction dissipators （including behavior for inputs containing pulses, capacity to reduce resonance peaks, introduction of high frequencies in the response, and self- generated eccentricities）, （iii） better understand their dynamic behavior, （iv） provide insight on the feasibility and reliability of using simple friction dissipators for seismic protection of building structures and （v） characterize the hysteretic behavior of these devices. Most of these objectives are satisfactorily reached and relevant conclusions are stated.

关键词： building structures earthquake engineering passive control friction energy dissipators experimentalverification shaking table tests

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

INFlUENCES OF DENSITY AND DIMENSION OF CARBON NANOTUBES ON THEIR FIElD EMISSION

引用

Acta Metallurgica Sinica(English letters) 2003年第4期16卷 302-308页

作者： Y.B.Zhu W.l.Wang C.G.Hu DepartmentofPhysics JiangsuNormalUniversitySuzhou221009ChinaManuscriptreceived25November2002 DepartmentofAppliedPhysics ChongqingUniversityChongqing400044China

The influences of density and dimension of carbon nanotubes on their electron emission from arrays are studied. The tip electric field of nanotubes, electric field enhancement factor, and optimum nanotube density are expressed by analytic equations. The theoretical analyses show that the field enhancement factor is sensitive to nanotube density, and can be sharply improved at a specific and optimum density. Some experiments have demonstrated these. Owning to electrostatic screening effect, the length of carbon nanotubes has little effect on their emission. A uniformly-distributed carbon nanotube array model is set up, and applied to analysis of carbon nanotube arrays. The results obtained here are in good agreement with the experimental data.

关键词： carbon nanotube array field emission optimum density

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Effect of Ni Content on Mechanical Properties and Corrosion Behavior of Al/Sn－9Zn－xNi/Cu Joints

引用

Journal of Materials Science & Technology 2012年第9期28卷 844-852页

作者： M.l.Huang N.Kang Q.Zhou Y.Z.Huang Key laboratory of liaoning Advanced Welding and Joining Technology School of Materials Science&EngineeringDMian University of TechnologyDalian 116024China

The effects of Ni content on the microstructure and the wetting behavior of Sn-9Zn-xNi solders on Al and Cu substrates, as well as the mechanical properties and electrochemical corrosion behavior of Al/Sn-9Zn-xNi/Cu solder joints, were investigated. The microstructure of Sn-gZn-xNi revealed that tiny Zn and coarsened Ni5Zn21 phases dispersed in theβ-Sn matrix. The wettability of Sn-9Zn-xNi solders on Al substrate was much better than that on Cu substrate. With increasing Ni content, the wettability on Cu substrate was slightly improved but became worse on Al substrate. In the Al/Sn-9Zn-xNi/Cu joints, an Al4.2Cu3.2Zn0.7 intermetallic compound （IMC） layer formed at the Sn-gZn-xNi/Cu interfaces, while an Al-Zn-Sn solid solution layer formed at the Sn-9Zn-xNi/Al interface. The mixed compounds of Ni3Sna and Al3Ni dispersed in the solder matrix and coarsened with increasing Ni content, thus leading to a reduction in shear strength of the Al/Sn-9Zn- xNi/Cu joints. Al particles were segregated at both interfaces in the solder joints. The corrosion potentials of Sn-9Zn-xNi solders continuously increased with increasing Ni content. The Al/Sn-9Zn-0.25Ni/Cu joint was found to have the best electrochemical corrosion resistance in 5% NaCl solution.

关键词： Al-Cu disslmilar-metal solder joint Sn-9Zn-xNi Microstructure Mechanicalproperties Electrochemical corrosion Corrosion potential

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

The evolution of Epstein-Barr virus detection in nasopharyngeal carcinoma

引用

Cancer Biology & Medicine 2018年第1期15卷 1-5页

作者： You Quan li Ni Sann Khin Melvin l.K.Chua Division of Radiation Oncology National Cancer Center Oncology Academic Clinical Program Duke-NUS Medical School

The detection of Epstein-Barr virus(EBV)in nasopharyngeal carcinoma(NPC)has evolved over the last40 years,transitioning from simple serological tests of latent viral infection to extremely sensitive measurements of

关键词：乳头状瘤病毒癌症临床症状进化鼻 EBV 实用程序 DNA

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Association Analysis for Quality Traits in a Diverse Panel of Chinese Sesame(Sesamum indicum l.)Germplasm

引用

Journal of Integrative Plant Biology 2013年第8期55卷 745-758页

作者： Wenliang Wei Yanxin Zhang Haixia lü Donghua li linhai Wang Xiurong Zhang Oil Crops Research Institute of the Chinese Academy of Agricultural Sciences Key Laboratory of Biology and Genetic Improvement of Oil CropsMinistry of Agriculture

The main objective of this study was to evaluate the potential of a sesame （Sesamum indicum l.） panel for association analysis, and investigate the genetic basis of oil content （OC）, protein content, oleic acid concentration, and linoleic acid concentration using association mapping. A panel of 216 sesame accessions was phenotyped in a multi-environment trial and fingerprinted with 608 polymorphic loci produced by 79 primers, including simple sequence repeats （SSRs）, sequence-related amplified polymorphisms （SRAPs）, and amplified fragment length polymorphisms （AFlPs）. Population structure analysis revealed two subgroups in the population. The Q model performed better for its ability to re-identify associations for the four traits at highly significant P-values compared to the other three mixed models. And a total of 35 and 25 associations for the four traits in 2010 and 2011 were identified, respectively, with the Q model after Bonferroni correction. Among those associations, only one for OC was re-identified in two environments, and several markers associated simultaneously with multiple traits were discovered. These results suggest the power and stability of the Q model for association analysis of nutritional traits in this sesame panel for its slight population stratification and familial relationship, which could aid in dissecting complex traits, and could help to develop strategies for improving nutritional quality.

关键词： Association mapping nutritional trait population structure Sesamum indicum l.

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

COORElATION ANAlYSIS OF SURFACE PRESSURE FlUCTUATIONS ON THREE EQUISPACED CYlINDERS

引用

Journal of Hydrodynamics 2001年第2期13卷 55-62页

作者： Dong, l.Y. Xu, Y.H. Huang, D.Q. Inst. of Appl. Math. and Mech. Shanghai Univ. Shanghai 200072 China

The fluctuating pressures on the surface of three circular cylinders in equispaced arrangement were measured simultaneously in the medium subcritical regime (Re=3×104). The distributions of their rms values and circumferential correlation were obtained in the spacing range from 1.25 to 6.0. The spatial correlation of pressures of two pressure taps on two different cylinders at the same azimuth was investigated as well. Owing to different flow patterns in various arrangements and spacing, these correlation curves of pressure show different distributions. The lift fluctuation can be estimated qualitatively from the circumferential coefficient curve with the knowledge of the rms pressure distribution. Some critical spacing for each arrangement were found that the flow regimes and the corresponding pressure correlation take a sudden change. Flow interference between cylinders in each arrangement was also discussed with various flow regimes.

关键词： Cylinders (shapes) Experiments Flow interactions Flow patterns Pressure distribution Pressure measurement

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

A unified approach to output synchronization of heterogeneous multi-agent systems via l2-gain design

引用

Control Theory and Technology 2017年第4期15卷 340-353页

作者： Shan Zuo Yongduan Song Hamidreza Modares Frank l. lewis Ali Davoudi School of Automation Engineering University of Electronic Science and Technology of China Chengdu Sichuan China The University of Texas at Arlington Research Institute Fort Worth U.S.A.

In this paper, a unified design procedure is given for output synchronization of heterogeneous multi-agent systems （MAS） on communication graph topologies, using relative output measurements from neighbors. Three different control protocols, namely, full-state feedback, static output-feedback, and dynamic output-feedback, are designed for output synchronization. It is seen that a unified design procedure for heterogeneous MAS can be given by formulation and solution of a suitable local l2-gain design problem. Sufficient conditions are developed in terms of stabilizing the local agents＇ dynamics, satisfying a certain small-gain criterion, and solving the output regulator equations. local design procedures are presented for each agent to guarantee that these sufficient conditions are satisfied. The proposed control protocols require only one copy of the leader＇s dynamics in the compensator, regardless of the dimensions of the outputs. This results in lower-dimensional compensators for systems with high-order outputs, compared to the p-copy internal model approach. All three proposed control protocols are verified using numerical simulations.

关键词： Heterogeneous systems output-feedback output synchronization small-gain theorem

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：