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classification of gradient space of dimension 8 by a reducible sl(2,c)action

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Science china Mathematics 2009年第12期52卷 2792-2828页

作者： YAU stephen S.-T. Institute of Mathematics East China Normal University Department of Mathematics University of Illinois at Chicago

This paper deals with a reducible sl(2,c)action on the formal power series *** purpose of this paper is to confirm a special case of the Yau conjecture:Suppose that sl(2,c)acts on the formal power series ring via(1.1).Then I(f)=(li 1 )⊕(il2 )⊕···⊕(lis)modulo some one dimensional sl(2,c)representations where(i)is an irreducible sl(2,c)representation of i dimension and{li1 ,li2 ,...,lis }{ll1,ll2,...,lr}.Unlike classical invariant theory which deals only with irreducible action and 1-dimensional representations,we treat the reducible action and higher dimensional representations successively.

关键词： principal ideal ring Steinberg group intermediate subgroups

Stability of fruit quality traits in diverse watermelon cultivars tested in multiple environments

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Horticulture Research 2016年第1期3卷 1-11页

作者： Mahendra Dia Todd c Wehner Penelope Perkins-Veazie Richard Hassell Daniel S Price George E Boyhan stephen M Olson stephen R King Angela R Davis Gregory E Tolla Jerome Bernier Benito Juarez Department of Horticultural Science North Carolina State UniversityRaleigh27695-7609NCUSA Plants for Human Health Institute North Carolina Research Campus NCSUKannapolis28081NCUSA clemson University Coastal Research and Education CenterCharleston29414SCUSA Georgia county Extension SW DistrictCordele31015GAUSA Department of Horticulture University of GeorgiaAthens30602GAUSA North Florida REc University of FloridaQuincy32351-5677FLUSA Department of Horticulture Science Texas A&M UniversityCollege Station77845TXUSA USDA-ARS Lane74555OKUSA Monsanto/Seminis Veg.Seeds Woodland95695CAUSA Sakata Seed America Inc.1833 Dunlap Pl.Woodland95776CAUSA

Lycopene is a naturally occurring red carotenoid compound that is found in *** has antioxidant *** content,sugar content and hollowheart resistance are subject to significant genotype×environment interaction(G×E),which makes breeding for these fruit quality traits *** objectives of this study were to(i)evaluate the influence of years and locations on lycopene content,sugar content and hollowheart resistance for a set of watermelon genotypes,and(ii)identify genotypes with high stability for lycopene,sugar,and hollowheart resistance.A diverse set of 40 genotypes was tested over 3 years and 8 locations across the southern United States in replicated,multi-harvest *** was tested in a subset of 10 *** were analyzed using univariate and multivariate stability statistics(BLUP-GGE biplot)using SASGxE and RGxE *** were strong effects of environment as well as G×E interaction on watermelon quality *** the basis of stability measures,genotypes were classified as stable or unstable for each quality trait.'crimson Sweet'is an inbred line with high quality trait performance as well as trait stability.'Stone Mountain','Tom Watson','crimson Sweet'and'Minilee'were among the best genotypes for lycopene content,sugar content and hollowheart *** developed a stability chart based on marketable yield and average ranking generated from different stability measures for yield attributes and quality *** chart will assist in choosing parents for improvement of watermelon *** http://***/cucurbit/wmelon/***.

关键词： stability. sugar stability

comparison of North American Seismic Screening Methods Applied to School Buildings

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Journal of civil Engineering and Architecture 2012年第7期6卷 799-811页

作者： Helene Tischer Denis Mitchell Ghyslaine mcclure Department of civil Engineering and Applied Mechanics McGill University Montreal QC H3A 0C3 Canada

An ongoing project at McGill University is aimed at developing an adapted seismic screening method for schools in the province of Qu6bec, canada. As part of this project the ＂FEMA 154 Rapid Visual Screening of Buildings for Potential Seismic Hazard＂ and the ＂NRc92 Manual for Screening of Buildings for Seismic Investigation＂ were used to assess 102 school buildings located in the city of Montr6al. Results for both methods are in reasonable agreement, with 65% of the buildings requiring a detailed evaluation according to FEMAI54 and 50% according to NRc92. Findings highlighted the particular characteristics of educational facilities： they are low rise buildings with high incidence of structural irregularities. Accounting for them in the screening phase is essential, and is better achieved by NRc92. However, this method is largely based on expert opinion, which makes it difficult to update, while FEMA154 uses a rational methodology for calculating vulnerability scores based on the capacity spectrum approach. The FEMA154 analytical procedure allows updating and adapting the method to its use outside its intended scope.

关键词： Seismic screening methods vulnerability schools.

一种支持产品平台设计的多准则模块划分方法（英文）

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2015年第1期16卷 1-10页

作者： Wei WEI Ang LIU stephen c.Y.LU Thorsten WUEST School of Mechanical Engineering and Automation Beihang University Aerospace and Mechanical Engineering Department University of Southern CaliforniaCA 90089 USA BIBA–Bremer Institut für Produktion und Logistik Gmb H Department of ICT Applications for ProductionHochschulring 20 Bremen 28359 Germany

目的:研究多准则约束下的产品模块划分方法,为企业建立稳健的模块化产品平台奠定基础。方法:采用改进的多目标进化算法对建立的多准则模块划分数学模型求解,并采用模糊集合评价机制进行最优解的寻取,得到基于多准则模块划分方法的产品... 详细信息

目的:研究多准则约束下的产品模块划分方法,为企业建立稳健的模块化产品平台奠定基础。方法:采用改进的多目标进化算法对建立的多准则模块划分数学模型求解,并采用模糊集合评价机制进行最优解的寻取,得到基于多准则模块划分方法的产品模块划分结果。结论:通过改进的多目标进化算法求解多准则模块划分模型,能够得到有效支持产品平台设计的产品模块划分方案。通过与已有优化方法的比较验证了本文提出的多准则模块划分方法的优越性。

关键词：模块划分模块化准则多目标优化改进的强度帕累托进化算法透平膨胀机

Biophysical activity of pulmonary surfactant: an alternative view

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Acta Pharmacologica Sinica 2003年第12期 156-157页

作者： stephen B HALL M/c NRc-3 Molecular Medicine OR 97201-3098 USA Oregon Health & Science University Portland

Pulmonary surfactant has long been recognized as a potential factor in the development and perpetuation of the acute respiratory distress syndrome(ARDS). Attempts to use therapeutic surfactants in the treatment of ARD... 详细信息

关键词： of that Biophysical activity of pulmonary surfactant an alternative view DPPc form

Electroless copper-phosphorus coatings with the addition of silicon carbide (Sic) particles

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International Journal of Minerals,Metallurgy and Materials 2011年第5期18卷 615-622页

作者： Soheila Faraji Afidah Abdul Rahim Norita Mohamed coswald stephen Sipaut School of chemical Sciences Universiti Sains Malaysia11800 USMPenangMalaysia School of Engineering and Information Technology Universiti Malaysia Sabah88999 Kota KinabaluSabahMalaysia

cu-P-silicon carbide （Sic） composite coatings were deposited by means of electroless *** effects of pH values,temperature,and different concentrations of sodium hypophosphite （NaH2PO2·H2O）,nickel sulfate （NiSO4·6H2O）,sodium citrate （c6H5Na3O7·2H2O） and Sic on the deposition rate and coating compositions were evaluated,and the bath formulation for cu-P-Sic composite coatings was *** coating compositions were determined using energy-dispersive X-ray analysis （EDX）.The corresponding optimal operating parameters for depositing cu-P-Sic are as follows：pH 9;temperature,90oc;NaH2PO2·H2O concentration,125 g/L;NiSO4·6H2O concentration,3.125 g/L;Sic concentration,5 g/L;and c6H5Na3O7·2H2O concentration,50 g/*** surface morphology of the coatings analysed by scanning electron microscopy （SEM） shows that cu particles are uniformly *** hardness and wear resistance of cu-P composite coatings are improved with the addition of Sic particles and increase with the increase of Sic content.

关键词： electroless deposited coating electroless copper plating silicon carbide particles sodium hypophosphite hardness wear resis-tance

Rapid growth in a large cambrian apex predator

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National Science Review 2024年第3期11卷 128-136页

作者：吴雨 stephen Pates Daniel Pauly 张兴亮傅东静 State Key Laboratory of continental Dynamics and Shaanxi Key Laboratory of Early Life and Environment Department of Geology Northwest University Department of Zoology University of Cambridge Institute for the Oceans and Fisheries University of British Columbia Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences

Despite the importance of ontogenetic data on early diverging euarthropods to our understanding of the ecology and evolution of past life, the data are distinctly lacking, as reconstructing life histories of fossil animals is often challenging. Here we report the growth trajectory of frontal appendages of the apex predator Amplectobelua symbrachiata, one of the most common radiodont arthropods from the early cambrian chengjiang biota(c. 520 Ma) of china. Analysis of 432 specimens(9.1–137.1 mm length; 1.3–25.6 mm height) reveals that appendages grew isometrically, with an estimated maximum size of the whole animal of c. 90 cm. Individuals grew rapidly compared to extant arthropods, as assessed using the electronic length-frequency analysis(ELEFAN) approach. Therefore, we show that the cambrian apex predator A. symbrachiata was an extremely fast-growing arthropod, with an unusual life history strategy that formed as part of the escalatory ‘arms race’ that shaped the cambrian explosion over 500 Ma.

关键词： stem-group Euarthropoda Radiodonta post-embryonic development growth dynamics cambrian Explosion

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图书情报科学的研究现状

图书馆 1992年第3期 67-70页

作者：陈曙 charles R.mcclure 上海师范大学图书馆 Syracuse大学图书情报学院

近年来,许多图书馆界的有识之士对图书情报学(简称LIS)产生了极大的兴趣。为此,他们期望吸引更多年富力强的图书情报专家,从中造就LIS研究的中坚骨干。这些人应当既重视基础研究,又不忽视应用研究,解决实际问题,从而推动学术工作的进展。

关键词：图书馆学情报学研究现状

carbon star cGcS 673 identified as a semi-regular variable star

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Research in Astronomy and Astrophysics 2020年第11期20卷 235-238页

作者： stephen M.Brincat charles Galdies Kevin Hills Flarestar Observatory(MPc 171) Fl.5/BGeorge Tayar StreetSan GwannSGN 3160Malta Institute of Earth Systems University of MaltaMsidaMSD 2080Malta Tacande Observatory(La Palma Spain)c/o 4 Grange DriveHartfordCheshire CW83AEUK

This study reports that the carbon star cGcS 673 is a semi-regular(SR)variable star with a period of 135 d and an amplitude of 0.18mag in the *** light curve obtained by this study correlates well with the SR classification as the photometric data obtained show noticeable periodicity in the light changes of cGcS 673 that is occasionally interrupted by a period of irregular *** derived period and colour index obtained from our data and those from professional databases indicate that the attributes of this star fall within the parameters of the SR class of variable *** our notification of the discovery that this star is a variable source,cGcS 673 has received the AAVSO Unique Identifier of(AAVSO UID)000-BMZ-492.

关键词： techniques photometric stars variables semi-regular variable stars individual cGcS