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Transition waves and nonlinear interactions in the near wake of a circular cylinder

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Science China Mathematics 1997年第8期40卷 849-859页

作者：凌国灿 allen T.Chwang 牛家玉王冬(女菱) Laboratory for Nonlinear Mechanics of Continuous Media Institute of MechanicsChinese Academy of SciencesBeijing 100080China Department of Mechanical Engineering University of Hong KongHong Kong Institute of Mechanics Chinese Acaderny of SciencesBeijing 100080China

Transition waves and interactions between two kinds of instability-vortex shedding and transition wave in the near wake of a circular cylinder in the Reynolds number range 3 000-10 000 are studied by a domain decomposition hybrid numerical *** on high resolution power spectral analyses for velocity new results on the Reynolds-number dependence of the transition wave frequency,***/fa^Re0.87 are *** new predictions are in good agreement with the experimental results of Wei and Smith but different from Braza’s prediction and some early experimental results ft/fa-Re0.5 given by Bloor et *** multi-interactions between two kinds of vortex are clearly visualized *** strong nonlinear interactions between the two independent frequencies (ft,fa) leading to spectra broadening to form the coupling mfs±nft are predicted and analyzed numerically,and the characteristics of the transition are *** variations of the transition wave and its coupling are reported.

关键词： transition wave nonlinear interaction near wake circular cylinder.

Erectile function after urethral reconstruction

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Asian Journal of Andrology 2008年第1期10卷 75-78页

作者： Joshua Carlton Maharshi Patel allen F. Morey Department of Urology UT Southwestern Medical Center Dallas Texas 75390-9110 USA

Advances in urogenital plastic surgical tissue transfer techniques have enabled urethral reconstruction surgery to become the new gold-standard for treatment of refractory urethral stricture disease. Questions remain, however, regarding the long-term implications on sexual function after major genital reconstructive surgery. In this article, we review the pathologic features of urethral stricture disease and urologic trauma that may affect erectile function （EF） and assess the impact of various specific contemporary urethroplasty surgical techniques on male sexual function.

关键词： urethral reconstruction urethral stricture erectile function sexual function

Potentially dangerous glacial lakes across the Tibetan Plateau revealed using a large-scale automated assessment approach

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Science Bulletin 2019年第7期64卷 435-445页

作者： Simon Keith allen Guoqing Zhang Weicai Wang TANDong Yao Tobias Bolch Department of Geography University of Zurich Key Laboratory of Tibetan Environmental Changes and Land Surface Processes Institute of Tibetan Plateau Research Chinese Academy of Sciences Center for Excellence in Tibetan Plateau Earth Sciences Chinese Academy of Sciences School of Geography and Sustainable Development University of St Andrews

Glacial lake outburst floods(GLOFs) are a major concern in the Himalaya and on the Tibetan Plateau(TP),where several disasters occurring over the past century have caused significant loss of life and damage to infrastructure. This study responds directly to the needs of local authorities to provide guidance on the most dangerous glacial lakes across TP where local monitoring and other risk reduction strategies can subsequently be targeted. Specifically, the study aims to establish a first comprehensive prioritisation ranking of lake danger for TP, considering both the likelihood and possible magnitude of any outburst event(hazard), and the exposure of downstream communities. A composite inventory of 1,291 glacial lakes(>0.1 km^2) was derived from recent remote sensing studies, and a fully automated and object assessment scheme was implemented using customised GIS tools. Based on four core determinates of GLOF hazard(lake size, watershed area, topographic potential for ice/rock avalanching, and dam steepness), the scheme accurately distinguishes the high to very high hazard level of 19 out of 20 lakes that have previously generated GLOFs. Notably, 16% of all glacial lakes threaten human settlements, with a hotspot of GLOF danger identified in the central Himalayan counties of Jilong, Nyalam, and Dingri, where the potential trans-boundary threat to communities located downstream in Nepal is also recognised. The results provide an important and object scientific basis for decision-making, and the methodological approach is ideally suited for replication across other mountainous regions where such first-order studies are lacking.

关键词： GLOF Hazard Exposure Danger Tibetan Plateau Himalaya

Automatic Synthesis of Batch Process Operating Procedures

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Chinese Journal of Chemical Engineering 1998年第1期6卷 46-53页

作者：王保国王春艳许锡恩 allen R.Wright Department of Chemical Engineering Tianjin University Batch CAD Ltd. Newcastle upon TyneNE14LEUK

A three-step synthesis strategy for the automatic synthesis of operating procedures in batch processoperations is presented in this *** first step is pre-operation which consists of a set of checks that mustbe considered before starting the basic process *** second step is operation which is described by a setof basic control *** third step is post-operation described by a set of instructions that must becarried out when the basic process operation is *** three-step synthesis method has been imple-mented as part of a prototype recipe management system.

关键词： batch process operating procedure control step

Mistaking Statistics for Rigor in American Business School Research： Should China Follow, or Lead in a New Direction？

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Frontiers of Business Research in China 2014年第4期8卷 411-434页

作者： allen S. Lee School of Business Virginia Commonwealth University Richmond VA 23284-4000 USA

The heavy emphasis on statistical rigor that business schools in American universities place on research is questionable in general and, for business schools in China, is not necessarily a good strategy by which either to produce useful research or to distinguish themselves from business schools in the United States. The reasons for this pertain to, first, what statistical analysis is good for in science; second, what statistical analysis is not good for in science; third, what statistical analysis is and is not good for in business research; fourth, how a large sample size is not generalizable but a single case is; fifth, how action research, design research, and Herbert Simon＇s ＂sciences of the artificial＂ all demonstrate rigor without statistics; and finally, the historical context that explains the turn to statistics in American business schools but is irrelevant to China. The recommendation is for business schools in China not necessarily to reject statistical research, but rather, to also pursue other, equally scientific forms of research, including those recognized by Herbert Simon.

关键词： philosophy of science,methodology sciences of the artificial,research business researchphilosophy of technology statisticaldesign science design research action

What Do Students Know about University Rankings?Testing Familiarity and Knowledge of Global and Domestic University League Tables in China

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Frontiers of Education in China 2019年第1期14卷 59-89页

作者： Ryan M.allen Attallah College of Educational Studies Chapman UniversityOrangeCA 92866USA

While academics and university administrators often criticize rankings,league tables have become important tools for student decision-making,especially in the Chinese ***,research has not fully explored how students in China have engaged with both global and local rankings,as most studies have focused on one setting or the ***,researchers have not tested students’knowledge of rankings,despite the intense focus on these actors by *** a survey of over 900 students from Chinese universities,the author explored how knowledge of rankings varies in different student *** multivariate analysis,it is found that students from elite institutions and those with educated parents were more attuned to university rankings in ***,when testing students’knowledge of rankings,elite university students performed better in knowing their domestic ranking,but worse when guessing their global ranking,while associations to parental education *** study,the first of its kind in terms of testing student knowledge,illustrates that the impact from university rankings are mitigated by local and individual characteristics.

关键词： China university rankings student perspective internationalization higher education metrics league tables

A Study on Retrieving Atmospheric Profiles from EOS/AIRS Observations

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Acta meteorologica Sinica 2005年第1期19卷 112-119页

作者：官莉 allen Huang 李俊 Department of Electronic Engineering Nanjing University ofInformation Science & Technology Nanjing 210044 China University of Wisconsin Madison WI 53705 USA

The paper presents the algorithms for retrieving atmospheric temperature andmoisture profiles and surface skin temperature from the high-spectral-resolution AtmosphericInfrared Sounder (AIRS) with a statistical technique based on principal component analysis. Thesynthetic regression coefficients for the statistical retrieval are obtained by using a fastradiative transfer model with atmospheric characteristics taken from a dataset of global radiosondesof atmospheric temperature and moisture profiles. Retrievals are evaluated by comparison withradiosonde observations and European Center of Medium-Range Weather Forecasts (ECMWF) analyses. AIRSretrievals of temperature and moisture are in general agreement with the distributions from ECMWFanalysis fields and radiosonde observations, but AIRS depicts more detailed structure due to itshigh spectral resolution (hence, high vertical spatial resolution).

关键词： AIRS (Atmospheric Infrared Sounder) principal component regression atmospheric profile retrieval

Cytogenetic Mechanism for the Aneuploidy and Mosaicism Foundin Tetraploid Pacific Oyster Crassostrea gigas （Thunberg）

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中国海洋大学学报：英文版 2014年第1期13卷 125-131页

作者： Zhang, Zhengrui Wang, Xinglian Zhang, Quanqi allen, Standish College of Marine Life Sciences Key Laboratory of Marine Genetics and Breeding of Ministry of Education Ocean University of China Qingdao P. R. China Aquaculture Genetics and Breeding Technology Center Virginia Institute of Marine Science College of William and Mary Gloucester Point USA

Chromosome constitution was investigated in adult tetraploid Pacific oyster produced by blocking the first polar body oftriploid eggs which were fertilized with haploid sperms. A high incidence of aneuploid and heteroploid mosaics were found amongthe offspring. Of 20 individuals identified, only 9 （45%） were eutetraploid which contained 40 chromosomes; 2 （10%） were ane-uploid （hypotetraploid）, which contained 39 and 38 chromosomes, respectively; and 9 （45%） were heteroploid mosaics. One mosaicwas consisted of cells containing 40 and 39 chromosomes, respectiovely （1：1 in cell number）, while the other 8 were consisted ofcells containing chromosomes varying between tetraploid and triploid. It was also interesting to note that 3 mosaics even containedsome diploid cells with 20 chromosomes. A certain number of cells of 2 tetraploids and 8 mosaics spread with 32-37 well-scatteredand some clumped chromosomes at metaphase. The percentage of aneuploid cells with chromosomes varying between triploid andtetraploid correlated significantly with that of heteroploid mosaics cells with clumping chromosomes （P〈0.05）. Our findings sug-gested that reversion existed in both tetraploid and triploid oyster and chromosome clumping may underline the chromosome elimi-nation in tetraploid oyster. It seems that the reversing cells, at least some of them, continuously eliminate their chromosomes until themost stable diploid state is established.

关键词： tetraploid oyster aneuploidy mosaicism reversion cytogenetic mechanism

Analysis of Oxides Formed on the Surface of the Alloy 690 in Hydrogenated Supercritical Water

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Acta Metallurgica Sinica(English Letters) 2016年第8期29卷 774-781页

作者： Jin Gao Fa-rong Wan Guo-ping Cao Kumar Sridharan Todd allen School of Materials Science and Engineering University of Science and Technology Beijing Department of Materials Science and Engineering University of Wisconsin-Madison

The oxides formed on the surface of the alloy 690 in hydrogenated supercritical water at 400℃ for 1000 h were investigated using scanning electron microscopy,transmission electron microscopy,scanning transmission electron microscopy and energy-dispersive X-ray *** oxides on me surface of the alloy 690 exhibited multi-layer structure：an outer layer consisted of granular crystallites（NiO and NiFe_2O_4） and a compact inner layer（spinel and Cr_2O_3）.Chemical analysis indicated that the outer layer was enriched in nickel but depleted in chromium,whereas the inner layer was enriched in chromium and iron but depleted in *** inner layer was also characterized as layered structure by Fe-rich spinel on top of continuous Cr_2O_3 ***,Cr_2O_3 nodules were readily observed at the oxides/alloy interface.

关键词： Alloy 690 Supercritical water Oxides Corrosion