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排序方式: 共有796条查询结果,搜索用时 15 毫秒
1.
Ph. D. Candidate:Chen Xue-fengState Key Laboratory of Offshore Coastal Engineering Dalian University of Technology Dalian China e-mail: cxfeng @ student dlut. edu.cn 《水动力学研究与进展(B辑)》2003,15(6)
The reflection coefficient of perforated caissons and the total horizontal forces acting on them were experimentally and numerically analyzed and discussed when wave propagates normally. To consider the viscosity effect of fluid and nonlinear action of waves on structures, the VOF (Volume Of Fluid) method combined with the k-ε turbulence model was used to simulate the interaction between waves and structures. Governing equations were solved with the finite difference method. Through 2D experimental study in the wave flume, the empirical relationship between the reflection coefficient of perforated caissons and the main affecting factors were obtained from the experimental data using the least square method. Also the correlation between the ratio of the total horizontal force acting on perforated caisson and the force acting on solid caisson and the main affecting factors were regressed from the experimental data. 相似文献
2.
On April th over participants among them business leaders IT engineers the enterprise representatives some standardization experts scholars from all over the world gathered in Beijing to attend the International Seminar on "WTO: Intellectual Property Right Issues In Standardization"…… 《中国标准化(英文版)》2007,(3):36-37
On April 17th 2007, over 200participants, among them business leaders, IT engineers, the enterprise representatives and some standardization experts and scholars from all over the world gathered in Beijing to attend the International Seminar on "WTO: Intellectual Property Right Issues In Standardization" 相似文献
3.
本刊讯:年香港公开模型大赛年月日至日在上环文娱中心举办.香港公开模型大赛始于年 至今已举办届.此项赛事是香港地区颇具规模的模型比赛 其影响力已辐射至内地 不时有内地模友赴港参赛并取得佳绩.…… 《模型世界》2007,(2):46-47
本刊讯:2006年香港公开模型大赛2006年12月2日至3日在上环文娱中心举办.香港公开模型大赛始于1998年,至今已举办10届.此项赛事是香港地区颇具规模的模型比赛,其影响力已辐射至内地,不时有内地模友赴港参赛并取得佳绩. 相似文献
4.
河南省科学技术厅 《中国制造业信息化》2003,32(5):16
制造业企业数量多是河南省的特点,为做好制造业信息化工作,在河南省政府的领导下,以科技厅为主,目前已经形成了其他相关部门积极配合的工作格局。 试点示范企业特色鲜明 河南省根据制造业企业的分布情况,在机械行业选定了开封空分、太行振动、郑纺机;在电子 相似文献
5.
Chen Bao-ming Zhang Li-qiangDepartment of Air-conditioning Refrigeration Engineering Shandong Institute of Architecture andEngineering Jinan China e-mail:chenbm @ sdai.edu.cnWang Bu-xuanDepartment of Thermal Engineering Tsinghua University Beijing China 《水动力学研究与进展(B辑)》2003,15(6)
The influences of Soret effect and Dufour effect on the natural convection and heat and mass transfer for a porous enclosure were investigated by means of the penalty finite element method. Numerical results indicate that the Soret and Dufour effects have significant influences on heat and mass transfer in the presence of large temperature gradient and concentration gradient. 相似文献
6.
. Introduction Lost Foam Casting has been introduced into China for two decades it is getting more popularity in foundry industry.In China there are two associations responsible for the LFC industry academic exchanges: Chinese Lost Foam Casting Society 《中国铸造》2007,4(3):240-242
1. Introduction
Lost Foam Casting has been introduced into China for two decades, and it is getting more popularity in foundry industry.In China there are two associations responsible for the LFC industry and academic exchanges: Chinese Lost Foam Casting Society (CLFCS) and Chinese Association of Full Mold Casting. 相似文献
7.
1.~nonNUInericalmodellingbythefiniteelement(FE)methodhasbecomeaneffectiveandeconomyicmeansforsimulatingmetalfoeingprocesses.However,accuratemodellingdemandsthecorrectdefinitionandinputsofthedataforthethermalandphysicalpIDPertiesoftheworkpieceandtoolmaterials,theboUndaryconditionsattheworkpiece--toolinterfaceandinotherareas,inadditiontoappropriatemeshgenerationandnumericalsolutions.Althoughmostofthematerialdataareavailable,thedataforinterfacialheattransferandfrictionconditions,Whichhavesubst… 相似文献
8.
JIN Nengyun Shanghai Jiaotong University Jin Nengyun Department of Materials Science Shanghai Jiaotong University Shanghai China.Present address:Max-Planck-Institut für Metallforschung Institut für Physik Stuttgart FRG 《金属学报(英文版)》1989,2(2):93-99
A dislocation interaction model has been proposed for cyclic deformation of fcc crystals.Ac-cording to this model,cyclic stress-strain responses and saturation dislocation structures of acrystal are associated with the modes and intensities of dislocation interactions between slipsystems active in the crystal; and,hence,may be predicted by the location of its tensile axis inthe crystallographic triangle.This model has successfully explained the different behaviours ofdouble-slip crystals and multi-slip behaviours of some crystals with orientations usually con-sidered as single-slip ones. 相似文献
9.
HUANG Zheng Institute of Physics Academia Sinica Beijing ChinaYAO Mei Harbin Institute of Technology Harbin China Correspondent:HUANG Zheng Post-doctorial Assistant Institute of Physics Academia Sinica Beijing China 《金属学报(英文版)》1990,3(4):282-286
In the light of analysis of the features of cleavage fractographs of low carbon steel,the stresscriterion for cleavage crack propagation across ferrite grain boundary was established on thesupposition that resistance to the propagation results from an arbitrary mutual orientation ofthe cleavage plans in the neighbouring grains.On the basis of concept of statistical distribu-tion of cleavage plane in space,the probabilistic characteristic of cleavage process was ex-pounded,and the fracture stress of the cracked specimen over temperature range in whichfracture is initiated by cleavage mechanism was calculated by means of finite element analysisprogram and the calculated result was found to be in agreement with that measured. 相似文献
10.
Nomen est omen: Under the motto "The Bright World of Metals"the four international technology trade fairs GIFA METEC THERMPROCESS NEWCAST drew to a successful close on Saturday. Over companies associations research institutes presented the latest innovations in the areas of foundry technology castings metallurgy thermal process engineering in Düsseldorf.…… 《中国铸造》2007,4(3):250-250
Nomen est omen: Under the motto "The Bright World of Metals"the four international technology trade fairs GIFA, METEC,THERMPROCESS and NEWCAST drew to a successful close on Saturday. Over 1 700 companies, associations and research institutes presented the latest innovations in the areas of foundry technology, castings, metallurgy and thermal process engineering in Düsseldorf. 相似文献