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On the Equivalence of Multiplicative Structures in Floer Homology and Quantum Homology

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Acta Mathematica Sinica,English Series 1999年第1期15卷 53-80页

作者： Gang Liudepartment of mathematics,UCLA,{2. angeles,ca 90095 usaGang Tiandepartment of mathematics,MIT,cambridge,MA 02.39,usa department of mathematics UCLA Los Angeles USA department of mathematics MIT Cambridge USA

In this paper,we will prove that Floer homology equipped with either the intrinsic or exterior product is isomorphic to quantum homology as a *** will also prove that GW-invariants in Floer homology and quantum homolo... 详细信息

关键词： Floer homology Quantum homology GW-invariants J-holomorphic curves Moduli space

Time-periodic solutions of the Einstein's field equations II:geometric singularities

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Science China mathematics 2010年第6期53卷 1507-1520页

作者： KONG DeXing1,LIU KeFeng2.& SHEN Ming3 1department of mathematics,Zhejiang University,Hangzhou 31002.,China 2.0} of mathematics,University of california at los angeles,ca 90095,usa 3Center of Mathematical Sciences,Zhejiang University,Hangzhou 31002.,China 1. department of mathematics Zhejiang University Hangzhou 310027 China2. Department of Mathematics University of California at Los Angeles Los Angeles CA 90095 USA3. Center of Mathematical Sciences Zhejiang University Hangzhou 310027 China

In this paper,we construct several kinds of new time-periodic solutions of the vacuum Einstein's field equations whose Riemann curvature tensors vanish,keep finite or take the infinity at some points in these space-times,*** singularities of these new time-periodic solutions are investigated and some new physical phenomena are discovered.

关键词： Einstein’s field equations time-periodic solution Riemann curvature tensor singularity event horizon

Posterior gut development in Drosophila:a model system for identifying genes controlling epithelial morphogenesis

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Cell Research 1998年第4期8卷 273-284页

作者： LENGYEL JUDITH A XUE JUN LIU (department of Molecular, Cell and Developmental Biology University of california at {2. angeles, {2. angeles, ca usa, 90095-1606 usa) department of Molecular Cell and Developmental Biology University of California at Los Angeles Los Angeles CA USA 90095-1606 USA

The posterior gut of the Drosophila embryo, consisting of hindgut and Malpighian tubules, provides a simple,well-defined system where it is possible to use a genetic approach to define components essential for epithelial *** review here the advantages of Drosophila as a model genetic organism, the morphogenesis of the epithelial structures of the posterior gut, and what is known about the genetic requirements to form these *** overview, primordia are patterned by expression of hierarchies of transcription factors; this leads to localized expression of cell signaling molecules, and finally, to the least understood step: modulation of cell adhesion and cell shape. We describe approaches to identify additional genes that are required for morphogenesis of these simple epithelia, particularly those that might play a structural role by affecting cell adhesion and cell shape.

关键词： Organogenesis cell rearrangement convergent extension hindgut Malpighian tubule

Classification of rational holomorphic maps from B^2.into B^N with degree 2

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Science China mathematics 2009年第12期52卷 2647-2667页

作者： JI ShanYu 1 & ZHANG Yuan 2.1 department of mathematics, University of Houston, Houston, TX 772.4,{2. 2.department of mathematics, University of california at San Diego, La Jolla, ca 92.93,{2. department of mathematics University of Houston Houston USA department of mathematics Rutgers University New Brunswick USA

Rational proper holomorphic maps from the unit ball in C 2.into the unit ball C N with degree 2.are classified, up to automorphisms of balls.

关键词： rational holomorphic maps between balls classification maps with degree 2

Analysis of Environmental and Socio-economic Determinants Affecting Population Longevity Level at County Level in China

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Chinese Journal of Population,Resources and Environment 2005年第1期3卷 36-41页

作者： Lu Jiehua , Wang Hongbo 1 2.& Pan Yi 1 1. Institute of Population Research, Peking University, Beijing 100871, China 2. department of Sociology, University of california at {2. angeles, {2. angeles, usa. Institute of Population Research Peking University Beijing 100871 China department of Sociology University of California at Los Angeles Los Angeles United States

Based on the current literature, this paper is mainly intended to test whether environmental factors and socio-economic factors will have direct effect on the longevity at county level in China in order to determine the major determinants affecting local longevity level. Using the multi-regression model, we find the result that factors such as temperature, climate, longitude, type of soils, as well as type of agricultural food production play a major role in shaping the longevity at county level, and that socio- economic factors like infant mortality and gross death rate also have some direct impact on longevity, but the degree of impact is not as strong as the above environmental factors.

关键词： longevity socio-economic factors environmental factors

An Efficient Algorithm for Mobile Localization in Sensor Networks

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International Journal of Automation and computing 2012年第6期9卷 594-599页

作者： Xin-Min Xu 1 Yao Chen 1 Wen-Yao Xu 2.Fang Gong 2.1 department of Information Science and Electronic Engineering,Zhejiang University,Hangzhou 31002.,China 2.Electrical Engineering department,University of {2.,los angeles 90095,usa 1. department of Information Science and Electronic Engineering Zhejiang University Hangzhou 310027 China 2. Electrical Engineering department University of California Los Angeles 90095 USA

Node localization is a fundamental problem in wireless sensor *** are many existing algorithms to estimate the locations of the ***,most of the methods did not consider the presence of *** practice,obstacles will lead to blockage and reflection of communication signals between sensor ***,the presence of obstacles will greatly affect the localization *** this paper,we implement an obstacle-handling algorithm based on the localization tool developed by MIT,The experimental result shows that the enhanced algorithm can reduce the average distance error by up to 46 %,compared to the original algorithm.

关键词： Wireless sensor network automatic localization intelligent computing optimization simulation.

On characterizations of isometries on function spaces

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Science China mathematics 2008年第4期51卷 620-631页

作者： LI SongYing~(1+) RUAN YingBin~2.1 department of mathematics University of {2. Irvine ca 92.97 usa 2.School of mathematics and Computer Science Fujian Normal University Fuzhou 350007 China 1. department of mathematics University of California Irvine CA 92697 USA 2. School of mathematics and Computer Science Fujian Normal University Fuzhou 350007 China

The paper gives characterization for an isometric isomorphism on little Bloch space, VMOA and holomorphic Besov space over the unit ball B n in ? n .

关键词： ismometry Besov spaces 32.17 47A15

POLES OF ZETA FUNCTIONS OF COMPLETE INTERSECTIONS

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Chinese Annals of mathematics,Series B 2000年第2期21卷 187-200页

作者： WAN DAQING(department of mathematics, University of {2., Irvine, ca 92.97-3875, usa.) department of mathematics University of California Irvine CA 92697-3875 USA

A vanishing theorem is proved for e-adic cohomology with compact support on an affine (singular) complete intersection. As an application, it is shown that for an affine complete intersection defined over a finite field of q elements, the reciprocal "poles" of the zeta function are always divisible by q as algebraic integers. A p-adic proof is also given, which leads to further q-divisibiliy of the poles or equivalently an improvement of the polar part of the AxKatz theorem for an affine complete intersection. Similar results hold for a projective complete intersection.

关键词： Pole Zeta function Complete intersection

A new sieve for distinct coordinate counting

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Science China mathematics 2010年第9期53卷 2351-2362页

作者： LI JiYou1 & WAN DaQing2.1department of mathematics,Shanghai Jiao Tong University,Shanghai 2.02.0,China 2.0} of mathematics,University of california,Irvine,ca 92.97-3875,usa 1. department of mathematics Shanghai Jiao Tong University Shanghai 200240 China2. Department of Mathematics University of California Irvine CA 92697-3875 USA

We present a new sieve for the distinct coordinate counting *** significantly improves the classical inclusion-exclusion sieve for this problem,in the sense that the number of terms is reduced from 2.k 2. to k!,and reduced further to p(k) in the symmetric case,where p(k) denotes the number of partitions of *** an illustration of applications,we give an in-depth study of a basic example arising from coding theory and graph theory.

关键词： sieve distinct coordinate counting