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MAXIMUM NORM ERROR ESTIMATES OF CROUZEIX-RAVIART NONCONFORminG FINITE ELEMENT APPROXIMATION OF NAVIER-STOKES PROBLEM

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Journal of Computational Mathematics 2000年第2期18卷 141-156页

作者： Qing-ping Deng Xue-jun Xu Shu-min shen Department of Mathematics University of TennessceU.S.A LSEC Institute of Computational MathematicsChinese Academy of SciencesP.O.Box 2719Beijing 100080China Department of Mathematics University of Suzhou 215006China

Presents information on a study which dealt with Crouzeix-Raviart nonconforming finite element approximation (FEA) of Navier-Stokes equation in a plane bounded domain by using velocity-pressure mixed formulation. Notations of Navier-Stokes problem and its nonconforming FEA; Description of linear nonconforming finite element spaces and their properties; Maximum-error estimates for C-R nonconforming FEA of stationary Navier-Stoke problem.

关键词： Navier-Stokes problem P1 nonconforming element maximum norm

Two MADS-box proteins,AGL9 and AGL15,recruit the FIS-PRC2 complex to trigger the phase transition from endosperm proliferation to embryo development in Arabidopsis

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Molecular Plant 2024年第7期17卷 1110-1128页

作者： shen Zhang Devasantosh Mohanty Adnan Muzaffar min Ni Department of Plant and Microbial Biology University of Minnesota at Twin CitiesSaint PaulMinnesota MN 55108United States of AmericaUSA

Spatiotemporal regulation of gene expression by polycomb repressive complex 2(PRc2)is critical for animal and plant *** Arabidopsis fertilization independent seed(FIS)-PRC2 complex functions specifically during plant reproduction from gametogenesis to seed *** a double fertilization event,triploid endosperm proliferates early,followed by the growth of a diploid embryo,which replaces the endosperm in Arabidopsis and many *** genes critical for endosperm proliferation such as IKkU2 and minI3 are activated after *** we report that two MADS-box AGAMOUS-LIKE(AGL)proteins associate with the key endosperm proliferation loci and recruit the FIS-PRC2 repressive complex at 4-5 days after pollination(DAP).Interestingly,AGL9 and AGL15 only accumulate toward the end of endosperm proliferation at 4-5 DAP and promote the deposition of H3K27me3 marks at key endosperm proliferation *** of AGL9 and AGL15 or overexpression of AGL9 or AGL15 significantly influence endosperm proliferation and ***-wide analysis with cleavage Under Targets and tagmentation(CUT&Tag)sequencing and RNA sequencing revealed the landscape of endosperm H3K27me3 marks and gene expression profiles in Col-0 and agl9 ***&Tag qPCR also demonstrated the occupancy of the two MADS-box proteins and FIS-PRC2 on a few representative target *** studies suggest that MADS-box proteins could potentially recruit PRc2 to regulate many other developmental processes in plants or even in fungi and animals.

关键词： AGL9 AGL15 embryo endosperm IKU2 MEDEA minI3

Vision based terrain reconstruction for planet rover using a special binocular bundle adjustment

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维普期刊数据库

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第10期9卷 1341-1350页

作者： min-yi shen Zhi-yu XIANG Ji-lin LIU Institute of Information and Communication Engineering Zhejiang University Hangzhou 310027 China Zhejiang Provincial Key Laboratory of Information Network Technology Zhejiang University Hangzhou 310027 China

This paper presents a pure vision based technique for 3D reconstruction of planet terrain. The reconstruction accuracy depends ultimately on an optimization technique known as 'bundle adjustment'. In vision techniques, the translation is only known up to a scale factor, and a single scale factor is assumed for the whole sequence of images if only one camera is used. If an extra camera is available, stereo vision based reconstruction can be obtained by binocular views. If the baseline of the stereo setup is known, the scale factor problem is solved. We found that direct application of classical bundle adjustment on the constraints inherent between the binocular views has not been tested. Our method incorporated this constraint into the conventional bundle adjustment method. This special binocular bundle adjustment has been performed on image sequences similar to planet terrain circumstances. Experimental results show that our special method enhances not only the localization accuracy, but also the terrain mapping quality.

关键词： 3D reconstruction Binocular bundle adjustment (BBA) Scale-invariant feature transform (SIFT) Re-projectionerror RANSAC

A retrospective study of the occurrence of ischemic-type biliary lesions post liver transplantation

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Science China(Life Sciences) 2016年第5期59卷 529-531页

作者： Rui Shi Ya-min Zhang Yong-Lin Deng Hong Zheng cheng Pan Zhong-Yang shen Tianjin Key Laboratory of Organ Transplantation Department of Hepatobiliary Surgery First Center Hospital Clinic Institute Tianjin Medical University

Dear Editors, lschemic-type biliary lesions （ITBLs） significantly reduce patient and graft survival rates. Research data regarding the causes of ITBL are rare. ITBLs is an important cause of post liver transplantation graft loss and patient death. The exact cause of this type of biliary complication remains un- clear. To establish strategies for ITBL treatment or preven- tion, the risk factors of ITBL must be elucidated. The objective of this single-center retrospective study was to investigate the risk factors of ITBL in orthotopic liver transplanta- tion （OLT） patients.

关键词：肝移植胆道病变血型预防方法风险因素危险因素存活率

Feasibility evaluation of failure models for predicting forming limit of metal foils

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Chinese Journal of Aeronautics 2020年第9期33卷 2461-2471页

作者： Bao MENG Jiejie SHI Yiyun ZHANG cheng cheng Bolin MA min WAN School of Mechanical Engineering and Automation Beihang UniversityBeijing 100083China

Forming limit of metal foil is an important index to evaluate its formability,and is of considerable significance to improve the quality of *** ductile fracture(DF)behavior in microscale plastic deformation is remarkably affected by the geometry and grain *** explore the size-dependent forming limit curve(FLC),the Holmberg and Marciniak tests of SUS304 foils with the thicknesses of less than 0.1 mm and diverse grain sizes were *** addition,the validity and feasibility of three types of existing failure models including Swift/Hill,MarciniakKuczynski(M-K)and DF criteria for predicting the micro-scaled FLCs were *** is found that the Swift/Hill model possesses the worst accuracy with predicting deviation above 50%.Four classical DF criteria including Freudenthal,Ayada,Brozzo and Oh show great difference,and Oh model considering plastic anisotropy presents the best *** predicted deviation of M-K model is aggravated with increasing grain size and decreasing foil thickness,which is attributed to the intensified free surface roughening and transformation of fracture mechanism with *** research thus provides a deeper understanding and valuable reference for the widespread application of FLC in microforming.

关键词： Failure criteria Forming limit Metal foil Microforming Size effect

Assimilation of GPM Microwave Imager Radiance for Track Prediction of Typhoon Cases with the WRF Hybrid En3DVAR System

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Advances in Atmospheric Sciences 2021年第6期38卷 983-993页

作者： Dongmei XU Feifei shen Jinzhong min Aiqing SHU The Key Laboratory of Meteorological Disaster Ministry of Education(KLME)/Joint International Research Laboratory of Climate and Environment Change(ILCEC)/Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters(CIC-FEMD)Nanjing University of Information Science&TechnologyNanjing 210044China Heavy Rain and Drought-Flood Disasters in Plateau and Basin Key Laboratory of Sichuan Province Chengdu 610225China

The impact of assimilating radiance data from the advanced satellite sensor GMI(GPM microwave imager)for typhoon analyses and forecasts was investigated using both a three-dimensional variational(3DVAR)and a hybrid ensemble-3DVAR *** interface of assimilating the radiance for the sensor GMI was established in the Weather Research and Forecasting(WRF)*** GMI radiance data are assimilated for Typhoon Matmo(2014),Typhoon Chan-hom(2015),Typhoon Meranti(2016),and Typhoon Mangkhut(2018)in the Pacific before their *** results show that after assimilating the GMI radiance data under clear sky condition with the 3DVAR method,the wind,temperature,and humidity fields are effectively adjusted,leading to improved forecast skills of the typhoon track with GMI radiance *** hybrid DA method is able to further adjust the location of the typhoon *** improvement of the track forecast is even more obvious for later forecast *** addition,water vapor and hydrometeors are enhanced to some extent,especially with the hybrid method.

关键词： WRF model GMI microwave imager data typhoon data assimilation

Nucleation of Bainite around Grain Boundary

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Journal of Materials Science & Technology 1998年第4期14卷 383-384页

作者： shen, Rong cheng, Juqiang Wang, Liuding Kang, Mokuang Northwestern Polytech Univ Dept Mat Sci & Engn Xian 710072 Peoples R China

The scanning Auger microprobe study on Fe-8Mn-1C alloy shows that the carbon atoms segregate at grain boundary during bainitic transformation and solute atoms depleted regions form near the grain boundary. The observation of optical and TEM indicates that bainite nucleates in solute atoms depleted regions near the grain boundary. (Edited author abstract) 11 Refs.

关键词： Iron alloys

Controllable precipitation of naproxen micro-particles with different morphologies

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Particuology 2012年第5期10卷 634-643页

作者： Peng cheng KangkangJin Jing cheng Fang Yang Zhigang shen Jianfeng Chen Lixiong Wen State Key Laboratory of Organic-lnorganic Composites Beijing University of Chemical TechnologyBeijing 100029China Research Center of the ministry of Education for High Gravity Engineering&Technology Beijing University of Chemical TechnologyBeijing 100029China

A simple precipitation method was proposed to prepare naproxen micro-particles with different controllable morphologies, using capillary video microscopy to study the precipitation process. Different particle shapes were obtained including spherical, platelet-like, stick-like, needle-like, and butterfly-like, all in the micro-size range. It was found that the sizes and morphologies of the formed naproxen particles were sensitive to the nature and concentration of the added surfactant, and depended significantly on processing conditions such as temperature, stirring speed, and initial drug concentration. In addition, pre- cipitation with different surfactant types and concentrations would not affect the crystal microstructure of the formed nanroxen oarticles.

关键词： PrecipitationCrystal growthNaproxenSurfactants

A Model Coupling Method for Shape Prediction

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Journal of Iron and Steel Research International 2012年第2期19卷 22-27页

作者： WANG Dong-cheng LIU Hong-min State Key Laboratory of Metastable Materials Science and Technology National Engineering Research Center forEquipment and Technology of Cold Rolling Strip Yanshan University Qinhuangdao 066004 Hebei China

The shape of strip is calculated by iterative method which combines strip plastic deformation model with rolls elastic deformation model through their calculation results, which can be called results coupling method. Be- cause the shape and rolling force distribution are very sensitive to strip thickness transverse distribution% variation, the iterative course is rather unstable and sometimes convergence cannot be achieved. In addition, the calculating speed of results coupling method is low, which restricts its usable range. To solve the problem, a new model cou- pling method is developed, which takes the force distribution between rolls, rolling force distribution and strip＇s exit transverse displacement distribution as basic unknowns, and integrates strip plastic deformation model and rolls elas- tic deformation model as a unified linear equations through their internal relation, so the iterative calculation between the strip plastic deformation model and rolls elastic deformation model can be avoided. To prove the effectiveness of the model coupling method, two examples are calculated by results coupling method and model coupling method re- spectively. The results of front tension stress, back tension stress, strip^s exit gauge, the force between rolls and rolling force distribution calculated by model coupling method coincide very well with results coupling method. How- ever the calculation course of model coupling method is more steady than results coupling method, and its calculating speed is about ten times as much as the maximal speed of results coupling method, which validates its practicability and reliability.

关键词： shape prediction results coupling method model coupling method strip plastic deformation rolls elas-tic deformation