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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 310027,China 2 Electrical Engineering department,University of california,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.

Heat flow distribution in Chinese continent and its adjacent areas

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Progress in Natural Science:Materials International 2008年第7期18卷 843-849页

作者： Wei Tao a,*, Zhengkang Shena,b a State Key Laboratory of Earthquake Dynamics, Institute of Geology, China Earthquake Administration, Beijing 100029, China b department of Earth and Space Sciences, University of california, los angeles, ca 90095-1567, usa State Key Laboratory of Earthquake Dynamics Institute of Geology China Earthquake Administration Beijing 100029 China department of Earth and Space Sciences University of California Los Angeles CA 90095-1567 USA

Using a compilation of 6980 heat flow measurements, we produce a new heat flow map for the Chinese continent and its adjacent areas. We develop an objective and integrated method to interpolate the heat flow data, taking into account both the uniformity within geological units and coherency of regional heat flow. The geologic units are outlined based on Zhang et al.’s active tectonic block model. Our heat flow model is presented in two formats: a contour map and a heat flow dataset with values on a 1×1° grid for the Chinese continent and its adjacent areas, reflecting detailed variations in some regions. Also provided is a resolution map which helps understand the reliability of the heat flow model. Our results reveal that (1) Heat flows in the eastern part of the Chinese continent are relatively higher than those in the western part except that in the Tibetan Plateau area. (2) Heat flows in the Ordos and North China blocks are around 60 mW/m2, and are 50–55 mW/m2 in South China except for the continental marginal sea regions. (3) Heat flow is the lowest in the Junggar Basin, only 35–45 mW/m2, and is 45–55 mW/m2 in the Tarim Basin. The results of this study provide an important data- set for studies on thermal and rheological structures of the Chinese continent and its adjacent areas.

关键词： Heat flow Chinese continent and its adjacent areas Geological units Contour map Resolution map

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 200240,China 2department of mathematics,University of california,Irvine,ca 92697-3875,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

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 california Irvine ca 92697 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 32A17 47A15

Characterization of Compact Support of Fourier Transform for Orthonormal Wavelets of L^2(R^d)

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Acta Mathematica Sinica,English Series 2005年第4期21卷 855-864页

作者： Zhi Hua ZHANG (Zhihua ZHANG) department of mathematics,University of california,Davis,california.95616,usa department of mathematics University of California Davis California 95616 USA

Let{ψμ} be an orthonormal wavelet of L^2（R^d） and the support of a whole of its Fourier transform be Uμsupp{ψμ}=Пi=1^d[Ai, Di]-Пi=1^d（Bi, Ci）, Ai≤Bi≤Ci≤Di. Under the weakest condition that each │ψμ│,... 详细信息

关键词： Orthonormal wavelets Multiresolution analysis Scaling function Compact support

Time-periodic solutions of the Einstein's field equations Ⅰ:general framework

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Science China mathematics 2010年第5期53卷 176-193页

作者： KONG DeXing1 & LIU KeFeng2 1department of mathematics,Zhejiang University,Hangzhou 310027,China 2department of mathematics,University of california at los angeles,ca 90095,usa

In this paper,we develop a new algorithm to find the exact solutions of the Einstein's field ***-periodic solutions are constructed by using the new *** singularities of the time-periodic solutions are investigated and some new physical phenomena,such as degenerate event horizon and time-periodic event horizon,are *** applications of these solutions in modern cosmology and general relativity are expected.

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

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 los angeles, los 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

FRACTURE TOUGHNESS OF ORDERED INTERMETALLIC COMPOUNDS FROM SMALL DISKSHAPED SPECIMENS

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中国有色金属学会会刊：英文版 1999年第S1期9卷 106-116页

作者： Alan J.Ardell department of Materials Science and Engineering, University of california, los angeles, ca 90095 1595, U.S.A.

The miniaturized disk bend test(MDBT) can be used to measure the fracture toughness at “infinite" crack length, K ∞, of ordered intermetallic compounds. The specimens tested are disks 3 mm in diameter and typically range in thickness from 250 to 400 μm. A Vickers indentation is impressed within ±10 μm of the center of a metallographically polished disk under a known load, F . The specimen is then subjected to biaxial loading, with the indented side in tension, and tested to failure. In completely brittle intermetallics the fracture stress, σ f, is calculated using a standard formula and measured experimentally as a function of F . When plasticity intervenes prior to fracture it is necessary to calculate the stress using finite element modeling (FEM), the FEM program NIKE2D has been used. Whether or not the specimens deform plastically, the resulting data on σ f vs F are analyzed using established equations of fracture mechanics in conjunction with an empirical rising R curve equation that characterizes the increase in fracture resistance, K R( c ), with crack length, c . Results are presented on several ordered intermetallic compounds. These include Ni 3Ge and Ti 5Si 3, which exhibit no ductility prior to fracture, and NiAl and a complex TiAl alloy, which both exhibit limited ductility before fracturing. The values of K ∞ determined with the MDBT are in very good agreement with values of K IC measured using conventional methods.

关键词： ordered intermetallics Ni 3Ge Ti 5Si 3 TiAl fracture toughness miniature disk bend test

TRAF-mediated regulation of immune and inflammatory responses

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Science China(Life Sciences) 2010年第2期53卷 159-168页

作者： WANG YaYa1,ZHANG Peng2,LIU YingFang2 & CHENG GenHong1 1 department of Microbiology,Immunology & Molecular Genetics,University of california los angeles,609 Charles E.Young Drive East,los angeles,california 90095,usa 2 National Laboratory of Biomacromolecules,Institute of Biophysics,Chinese Academy of Sciences,Beijing 100101,China 1. department of Microbiology Immunology & Molecular Genetics University of California Los Angeles 609 Charles E. Young Drive East Los Angeles California 90095 USA2. National Laboratory of Biomacromolecules Institute of Biophysics Chinese Academy of Sciences Beijing 100101 China

The tumor necrosis factor (TNF) receptor-associated factor (TRAF) family consists of six mammalian members,and is shown to participate in signal transduction of a large number of receptor families including TNF receptor family (TNFR) and Toll-like receptors-interleukin-1 receptors (TLR-IL-1R) *** receptor activation,TRAFs are directly or indirectly recruited to the intracellular domains of these *** subsequently engage other signaling proteins to activate inhibitor of κB kinase (IKK) complex,TRAF family member-associated NF-κB activator (TANK)-binding kinase 1 (TBK1) and inducible I κB kinase (IKK-i) (also known as IKKε),ultimately leading to activation of transcription factors such as NF-κB and interferon-regulatory factor (IRF) to induce immune and inflammatory responses.

关键词： TRAF NF-κB type 1 interferon innate immunity