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DETERMINATION OF BLANK HOLDER FORCE IN SHEET METAL DEEP DRAWING PROCESS

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Acta Metallurgica Sinica(English Letters) 2003年第1期16卷 31-34页

作者： y.J.Luo y.q.zhang D.N.He Department of Plasticity Technology Shanghai Jiao Tong University Shanghai 200030 China

Blank holder force (BHF) is an important measure to control the sheet metal forming. BHF is identified quickly using artificial neural network (ANN) on the basis of its analytical description. And critical rupture and... 详细信息

关键词： blank holder force sheet metal deep drawing artificial neural network

PHySICAL SIMULATION BASED INTELLIGENT SySTEM FOR THE PREDICTION OF SHEET METAL DRAWING CAPABILITy

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Acta Metallurgica Sinica(English Letters) 2000年第2期13卷 451-458页

作者： D.Lv D.N.He X.J.Bao y.q.zhang X.y.Ruan J.L.Cheng J.y.Jiang National Die&Mold CAD Engineering Research Center Shanghai Jiaotong UniversityShanghai 200030China Shanghai Volkswagen Automotive Company Limited Shanghai 201805China

With the combination of a new theoretical formula, physical simulation experiments, the technology of artificial neural network and database, an intelligent system for the prediction of sheet metal drawing capability is constructed for the first time. A modified criterion for sheet metal drawing capability is proposed in this paper, namely, the Technological Limiting Drawing Ratio, TLDR = f(R, n, s, t, F, μ,r_d,r_p…). Based on the studies of other scholars, a new formula is derived to predict the TLDR in this paper. Then a series of orthogonal physical simulation experiments are designed to investigate the effect of technological parameters on the TLDR, and the results are analyzed in the paper. Then the predicting system is constructed with the combination of the theoretical formula, orthogonal experiments, the technology of artifocial neural network and database. The predicted results show good agreements with experimental data, so it can be used to avoid the blindness in the selection of sheet metal before stamping. The system operates under the Windows operating system, and it supports the mechanism of Client/Server as well as Intranet, so the system has high engineering value.

关键词： TLDR theoretical analysis physical simulation orthogonal experiments neural network database predicting system

Effects of processing maize grains and soyabean on rumen fermentation and development of Holstein bull calves

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Effects of processing maize grains and soyabean on rumen fer...

多中心骨关节炎病人半月板内后根部撕裂与内侧胫股软骨损伤严重程度的相关性研究

The Ⅶ International Symposium on the Nutrition of Herbivores(ISNH-7)

作者： y.q.zhang X.Z.Deng Z.M.Zhou L.P.Ren q.X.Meng~1 State Key Laboratory of Animal Nutrition Beef Cattle Research Center and College of Animal Science and Technology China Agricultural University Beoing 100094 P.R.China

＜正＞A feeding trial using 12 Holstein bull calves（21±3 d）was conducted to investigate the effect of different processed maize grain and full fat soyabean included in the starter diets on their rumen fermentation and *** treatment starter diets contained different processed maize grain and soyabean:steam-flaked maize and soyabean（SFMS）,extruded maize and soyabean （EMS）,and ground maize and raw soyabean（GMS）.During 10-week trial,total rumen VFA concentration tended to be influenced by different processing methods at wk 6 and 9（P＜0.10）. The molar proportion of butyrate for calves receiving SFMS starter diets was higher than that of EMS and GMS starter diets（P＜0.05）at wk 5 and *** papillae development characteristics expressed by papilla length,papilla width and rumen wall thickness were remarkably different among treatment starter diets（P＜0.05）.

关键词： calves processing maize grain full fat soyabean rumen development

来源： cnki会议评论

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国际医学放射学杂志 2013年第6期 575-576页

作者： A.Guermazi D.Hayashi M.Jarraya F.W.Roemer y.q.zhang J.B.Niu 李京津 quantitative Imaging Center Department of Radiologyand Clinical Epidemiology Research & Training Unit Boston University School of Medicine 820 Harrison AveBoston MA 02118

摘要目的评估半月板内后根部撕裂与胫股软骨损伤的发展或严重度的相关性。材料与方法本研究经机构审查委员会批准,所有研究对象均签署知情同意书。在多中心骨

关键词：软骨损伤严重度严重程度严重率骨关节炎睑板软骨半月板病人

HyBRID LINEAR AND qUADRATIC FINITE ELEMENT MODELS FOR 3D HELMHOLTZ PROBLEMS

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Acta Mechanica Solida Sinica 2013年第6期26卷 603-618页

作者： q.H.zhang K.y.Sze Guangdong Province Key Laboratory of Computational Science Sun Yat-Sen University Department of Mechanical Engineering The University of Hong KongPokfulam

In this paper, linear and quadratic finite element models are devised for the three- dimensional Helmholtz problem by using a hybrid variational functional. In each element, contin- uous and discontinuous Helmholtz fields are defined with their equality enforced over the element boundary in a weak sense. The continuous field is based on the C° nodal interpolation and the discontinuous field can be condensed before assemblage. Hence, the element can readily be in- corporated seamlessly into the standard finite element program framework. Discontinuous fields constructed by the plane-wave, Bessel and singular spherical-wave solutions are attempted. Nu- merical tests demonstrate that some of the element models are consistently and considerably more accurate than their conventional counterparts.

关键词： finite element hybrid Helmholtz Bessel plane-wave spherical-wave radial basis function

Corrosion behavior of 13Cr stainless steel under stress and crevice in high pressure CO_(2)/O_(2)environment

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Journal of Materials Science & Technology 2021年第29期88卷 79-89页

作者： G.y.Zhu y.y.Li B.S.Hou q.H.zhang G.A.zhang Key Laboratory of Material Chemistry for Energy Conversion and Storage Ministry of EducationHubei Key Laboratory of Materials Chemistry and Service FailureSchool of Chemistry and Chemical EngineeringHuazhong University of Science and TechnologyWuhan430074China

In this work,through the self-developed setup for in situ electrochemical tests,the corrosion behavior of 13 Cr stainless steel under the combined effect of stress and crevice in high pressure CO_(2)/O_(2)environment was *** results show that 13 Cr stainless steel presents a self-passivation *** the action of stress,the anodic dissolution process of steel inside crevice is *** is a galvanic effect between the stressed steel inside crevice and the unstressed steel outside *** applied stress reduces the induction stage of crevice corrosion and induces a larger galvanic current,i.e.,the applied stress promotes the development of crevice ***,adding 0.1 MPa O_(2)is conducive to forming a more stable passive film but causes a greater galvanic effect.

关键词： Stainless steel Crevice corrosion Stress corrosion Galvanic effect

A new type of oceanic crust and its dynamical significance

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Chinese Science Bulletin 1997年第1期42卷 54-57页

作者： zhang, q Zhou, DJ Chen, y Institute of Geology Chinese Academy of Sciences Beijing China

THE oceanic lithosphere is composed of oceanic crust and upper mantle. It is widely accepted that the Troodos ophiolitic section represents the oceanic crust section, which consists of ultramafic cumulates in the bottom, and grades upward into cumulative gabbros, isotropic gabbro, sheeted dikes and pillow lavas, covered by abyssal sediments. According to the marine geophysical investigation, the oceanic crust can be divided into three layers which from top to bot-

关键词： oceanic crust ophiolite oceanic ridge dynamics.

Tuning the microstructure for superb corrosion resistance in eutectic high entropy alloy

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Journal of Materials Science & Technology 2022年第14期109卷 197-208页

作者： S.Shuang q.yua X.Gao q.F.He J.y.zhang S.q.Shi y.yang Department of Mechanical Engineering City University of Hong KongKowloon TongKowloonHong KongChina Department of Mechanical Engineering Hong Kong Polytechnic UniversityHung HomKowloonHong KongChina Department of Materials Science and Engineering City University of Hong KongKowloon TongKowloonHong KongChina

In this work,we demonstrate that the corrosion resistance of the FeCrNiCoNb_(0.5) eutectic high entropy alloy(EHEA)can be tuned by controlling the size of its eutectic *** microstructure refinement,the EHEA exhibits a superb corrosion resistance in 1 M NaCl in terms of a very low corrosion current density and an ultra-high transpassviation potential,which outperforms a variety of other HEAs and conventional metals and *** the fundamental level,the microstructure refinement results in a rapid formation of a thick and compact passive film with less Cl-adsorption on the EHEA,which results in significant enhancement in its corrosion *** outcome of our research provides important insights into the design of corrosion resistant chemically complex alloys.

关键词： Eutectic high entropy alloy Passivation Transpassivation potential Microstructure size

On Pattern Avoiding Flattened Set Partitions

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Acta Mathematica Sinica,English Series 2015年第12期31卷 1923-1928页

作者： Thomas y.H.LIU Andy.q.zhang Department of Foundation Courses Southwest Jiaotong University Center for Combinatorics LPMC-TJKLCNankai University

Let Π = B1/B2/… /Bk be any set partition of[n]= {1,2,...,n} satisfying that entries are increasing in each block and blocks are arranged in increasing order of their first *** Callan defined the flattened Π to be the permutation of[n]obtained by erasing the divers between its blocks,and Callan also enumerated the number of set partitions of[n]whose flattening avoids a single3-letter *** posed the question of counting set partitions of[n]whose flattening avoids a pattern of length *** this paper,we present the number of set partitions of[n]whose flattening avoids one of the patterns：1234,1243,1324,1342,1423,1432,3142 and 4132.

关键词： Set partition pattern avoidance flattened partition