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SECOND ORDER APPROXIMATION SOLUTION OF NONLINEAR LARGE DEFLECTION PROBLEMS OF YONGJIANG RAILWAY BRIDGE IN NINGBO

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Applied Mathematics and Mechanics(English Edition) 2002年第5期23卷 493-506页

作者： CHIEN wei-zang(钱伟长) Shanghai Institute of Applied Mathematics and Mechanics Shanghai University Shanghai 200072 P R China

The solution and computational aspects on nonlinear deflection of Yongjiang Railway Bridge in Ningbo were investigated. An approximate iteration algorithm on nonlinear governing equation was presented, and the obtained results show that, if altitude difference and span of the riverbanks are taken as 5 meters and 100 meters, respectively, the maximum gradient in the middle of the bridge exceeds 5%, much larger than maximum allowance gradient in railway design code. Therefore, a new solution scheme for decreasing gradient of the bridge is put forward, that is, the altitude difference between two riverbanks can be decreased to about 1/10 of the initial magnitude by building roadbeds with 0.5% gradient and 1 kilometer length at two riverbanks. As a direct result, the deflection gradient of the railway bridge is much reduced and the value is between 0.5% similar to 0.6%.

关键词： large deflection elastic modulus cantilever beam

Seed Dynamics in Relation to Gaps in a Tropical Montane Rainforest of Hainan Island,South China:(Ⅰ)Seed Rain

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Journal of Integrative Plant Biology 2007年第11期49卷 1565-1572页

作者： Run-Guo zang wei-Yin Zhang Yi Ding Kay Laboratory of Forest Ecology and Environment the State Forestry Administration Institute of Forest Ecology Environment and Protection Chinese Academy of Forastry Beijing 100091 China

Seed dynamics is an important part of stand dynamics in forest ecosystems. In this paper, 26 gaps were randomly selected to study the influence of gaps on the spatial and temporal patterns of seed rains in a tropical montane rainforest of Hainan Island, South China. Three zones for each gap, including outside gap zone （Non-gap）, transitional gap zone （EG-CG）, and central gap zone （CG）, were designed, and fourseed traps （each lm x lm in size） were placed in each zone. Seed rains were collected by these traps every 10 days from June 2001 to May 2002. Seed rain varied greatly with season and generally exhibited a pattern of unimodal change during the study period： seed abundance and species richness were both greater in the wet season than in the dry season. Gaps significantly influenced the temporal patterns of both species richness and density of seed rains. Gaps had no significant influences on the spatial distribution patterns of seed rain species richness, but significantly affected the spatial distribution pattern of seed rain densities. Among the three different zones of gaps, the outside gap zone generally received more seeds inputs than the two other gap zones.

关键词： forest regeneration gap dynamics Hainan Island seed dispersal seed rain supply-side process tropical montane rain forest.

Using interacting multiple model particle filter to track airborne targets hidden in blind Doppler

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第8期8卷 1277-1282页

作者： DU Shi-chuan SHI Zhi-guo zang wei CHEN Kang-sheng Department of Information and Electronie Engineering Zhejiang University Hangzhou 310027 China

In airborne tracking,the blind Doppler makes the target undetectable,resulting in tracking difficulties. In this paper,we studied most possible blind-Doppler cases and summed them up into two types:targets' intentional tangential flying to radar and unintentional flying with large tangential speed. We proposed an interacting multiple model(IMM) particle filter which combines a constant velocity model and an acceleration model to handle maneuvering motions. We compared the IMM particle filter with a previous particle filter solution. Simulation results showed that the IMM particle filter outperforms the method in previous works in terms of tracking accuracy and continuity.

关键词： Interacting multiple model Particle filter Blind Doppler

The Effect of Attendance Patterns on the Lek Mating System in the Omei Treefrog(Rhacophorus omeimontis)

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Asian Herpetological Research 2020年第4期11卷 320-327页

作者： Yue GUO Wenxia WANG wei zang Hui WANG Chenliang LI Mian ZHAO Hua WU Institute of Evolution and Ecology School of Life SciencesCentral China Normal UniversityWuhan 430079HubeiChina

Attendance patterns are a key factor affecting sexual selection and mating systems in lekbreeding ***,there are few systematic studies on attendance patterns in lek-breeding *** this study,we monitored a population of Omei treefrogs(Rhacophorus omeimontis) for four consecutive years to reveal in detail the effects of attendance patterns on mating *** found that(1) female nightly attendance was affected by male nightly attendance,and operational sex ratios(determined by male and female nightly attendance) ultimately determined the extent of female polyandry;(2) males surviving more than one breeding season maintained high chorus attendance and mating success,suggesting that male chorus attendance is a good predictor of male genetic quality;(3) the distributions of male mating success were not significantly different from a Poisson distribution,indicating a random mating pattern;and male mating success was not related to body size(size-assortative mating was not evident) but was significantly correlated with chorus *** the chorus attendance is a predictor of male genetic quality,females performing random mating were more likely to mate with more frequently present males and could therefore gain indirect benefits from mating with higher-than-average quality males,thereby producing good offspring without incurring the significant costs involved in prolonged searching for,and assessing *** systematic survey on the relationship between attendance patterns and the lek mating system in *** could help us better understand in-depth anuran lek mating systems.

关键词： attendance genetic quality lek mating random mating Rhacophorus omeimontis

Finite Element Analysis of Axisymmetric Elastic Body Problems

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Applied Mathematics and Mechanics(English Edition) 1980年第1期1卷 23-34页

作者： Chien, wei-zang(Tsing Hua University, Peking) Tsing Hua University Peking

Linear form functions are commonly used in a long time for a toroidal volume element swept bya triangle revolved about the symmetrical axis for general axisymmetrical stress *** is diffi-cult to obtain the rigidity matrix by exact integration,and instead,the method of approximate in-tegration is *** the locations of element close to the symmetrical axis,the accuracy of this ap-proximation deteriorates very *** exact integration have been suggested by various authorsfor the calculation of rigidity ***,it is shown in this paper that these exact integrationscan only be used for those axisymmetric bodies With central *** solid axisymmetric body,itcan be proved that the calculation fails due to the divergent property of rigidity matrix *** this paper a new form function is *** this new form function,the radial displacementu vanishes as radial coordinates r approach to *** calculated rigidity matrix is convergenteverywhere,including these triangular

关键词： Finite Element Analysis of Axisymmetric Elastic Body Problems

Masses for free-floating planets and dwarf planets

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Research in Astronomy and Astrophysics 2021年第6期21卷 207-221页

作者： Andrew Gould wei-Cheng zang Shude Mao Su-Bo Dong Max-Planck-Institute for Astronomy Konigstuhl 17D-69117 HeidelbergGermany Department of Astronomy Ohio State University140 W.18th Ave.ColumbusOH 43210USA Department of Astronomy Tsinghua UniversityBeijing 100084China National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China Kavli Institute for Astronomy and Astrophysics Peking UniversityBeijing 100871China

The mass and distance functions of free-floating planets(FFPs) would give major insights into the formation and evolution of planetary systems, including any systematic differences between those in the disk and bulge. We show that the only way to measure the mass and distance of individual FFPs over a broad range of distances is to observe them simultaneously from two observatories separated by D ~ O(0.01 au)(to measure their microlens parallax πE) and to focus on the finite-source point-lens(FSPL) events(which yield the Einstein radius θE). By combining the existing KMTNet 3-telescope observatory with a 0.3 m 4 deg2 telescope at L2, of order 130 such measurements could be made over four years, down to about M ~ 6 M⊕for bulge FFPs and M ~ 0.7 M⊕for disk FFPs. The same experiment would return masses and distances for many bound planetary systems. A more ambitious experiment, with two 0.5 m satellites(one at L2 and the other nearer Earth) and similar camera layout but in the infrared, could measure masses and distances of sub-Moon mass objects, and thereby probe(and distinguish between) genuine sub-Moon FFPs and sub-Moon "dwarf planets" in exo-Kuiper Belts and exo-Oort Clouds.

关键词： gravitational lensing:micro

Novel method for the determination of five carbamate pesticides in water samples by dispersive liquid-liquid microextraction combined with high performance liquid chromatography

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Chinese Chemical Letters 2009年第2期20卷 213-216页

作者： Zhi Mei Liu Xiao Huan zang wei Hua Liu Chun Wang Zhi Wang Key Laboratory of Bioinorganic Chemistry College of Sciences Agricultural University of Hebei Baoding 071001 China

A novel method for the determination of five carbamate pesticides （metolcarb, carbofuran, carbaryl, isoprocard and diethofencard） in water samples was developed by dispersive liquid-liquid microextraction （DLLME） coupled with high performance liquid chromatography-diode array detector （HPLC-DAD）. Some experimental parameters that influence the extraction efficiency were studied and optimized to obtain the best extraction results. Under the optimum conditions for the method, the calibration curve was linear in the concentration range from 5 to 1000 ng mL^-1 for all the five carbamate pesticides, with the correlation coefficients （r^2） varying from 0.9984 to 0.9994. Good enrichment factors were achieved ranging from 80 to 177- fold, depending on the compound. The limits of detection （LODs）（S/N = 3） were ranged from 0.1 to 0.5 ng mL^-1. The method has been successfully applied to the analysis of the pesticide residues in environmental water samples.

关键词： Carbamate pesticides High performance liquid chromatography Diode array detection Dispersive liquid-liquid microextraction Water samples

Nuclear Factor-κB Signaling Pathway Constitutively Activated in Esophageal Squamous Cell Carcinoma Cell Lines and Inhibition of Growth of Cells by Small Interfering RNA

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Acta Biochimica et Biophysica Sinica 2006年第5期38卷 318-326页

作者： Fang TIAN wei-Dong zang wei-Hong HOU Hong-Tao LIU Le-Xun XUE Laboratory for Cell Biology,Medical College,Zhengzhou University,Zhengzhou 450052,China Laboratory for Cell Biology Medical College Zhengzhou UniversityZhengzhou 450052 China

Although constitutive nuclear factor(NF)-kB activation has been reported in many humantumors,the role of the NF-kB pathway in esophageal squamous cell carcinoma(ESCC)has not been *** this study,NF-kB pathway in two ESCC cell lines was investigated using immunocytochemistry,Westernblot and reverse transciiption-polymerase chain *** activation of NF-kB DNA binding was determinedby electrophoretic mobility-shift *** interference was used to specifically inhibit the expression *** of cells Was evaluated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide *** results showed that p50,p65,IkBα,p-IkBα and IkB kinase β were expressed and mainly localized in *** transcription-polymerase chain reaction results showed the constitutive expressions ofp50,p65 and IkBα mRNA in the two ESCC cell ***,the nuclear extracts revealed that p50and p65 translocated to the nucleus had DNA-binding ***,small interfering RNA of p65 decreasedthe expression of p65,and the viability of ceils transfected with p65 small interfering RNA was significantlysuppressed at the same concentration of 5-fluorouracil(P<0.05)compared to untransfected *** resultsof this study showed that there was the constitutively activated NF-kB signaling pathway in the ESCC *** interference targeting at p65 increased the sensitivity of the ESCC cell lines to 5-fluorouracil,suggesting that NF-kB might be a good target for cancer treatment.

关键词： NF-κB RNA interference esophageal squamous cell carcinoma IκBα IκBα kinase

ASSUMPTIONS IN SAINT-VENANTS SOLUTION FOR THE TORSION OF AN ELASTIC CYLINDER

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Science in China,Ser.A 1954年第2期 165-170页

作者： CHIEN wei-zang Tsing Hua University

Saint-Venant used a set of physical assumptions in his semi-inversemethod for the torsion of an elastic cyclinder. These assumptions areequivalent to the following four conditions: σx =σy=τxy=σz=0. （1） Later researches by A. Clebsch and W. Voigt have resulted insimplifications of Saint-Venant’s analysis. Clebsch showed that the assumptionthat σz=0 is really not necessary. Instead of （1）, the following three assump-tions are sufficient for Saint-Venant’s solution:

关键词： ASSUMPTIONS IN SAINT-VENANTS SOLUTION FOR THE TORSION OF AN ELASTIC CYLINDER