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Latest progress on interactions between VLF/ELF waves and energetic electrons in the inner magnetosphere

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Science china Earth Sciences 2010年第3期53卷 317-326页

作者： XIAO FuLiang1,2. ZONG QiuGang3, SU ZhenPeng4, TIAN Tian3 & ZHENG HuiNan4 1 School of Physics and Electronic Sciences, Changsha university of Science and Technology, Changsha 410004, china 2.State Key Laboratory of Space Weather, Chinese Academy of Sciences, {2. 100190, china 3 Institute of Space Physics and Applied Technology, Peking university, {2. 100871, china 4 CAS Key Lab for Basic Plasma Science, School of Earth and Space Sciences, university of Science and Technology of china, Hefei 2.002., china 1. School of Physics and Electronic Sciences Changsha University of Science and Technology Changsha 410004 China2. State Key Laboratory of Space Weather Chinese Academy of Sciences Beijing 100190 China3. Institute of Space Physics and Applied Technology Peking University Beijing 100871 China4. CAS Key Lab for Basic Plasma Science School of Earth and Space Sciences University of Science and Technology of China Hefei 230026 China

Interactions between very/extremely low frequency (VLF/ELF) waves and energetic electrons play a fundamental role in dynamics occurring in the inner magnetosphere. Here, we briefly discuss global properties of VLF/ELF waves, along with the variability of the electron radiation belts associated with wave-particle interactions and radial diffusion. We provide cases of electron loss and acceleration as a result of wave-particle interactions primarily due to such waves, and particularly some preliminary results of 3D evolution of phase space density from our currently developing 3D code. We comment on the existing mechanisms responsible for acceleration and loss, and identify several critical issues that need to be addressed. We review latest progress and suggest open questions for future investigation.

关键词： wave-particle interaction VLF/ELF waves energetic electrons acceleration and loss inner magnetosphere

ON CONVERGENCE OF NOUREIN ITERATIONS FOR SIMULTANEOUS FINDING ALL ZEROS OF A POLYNOMIAL

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Journal of Computational Mathematics 2000年第2期18卷 113-122页

作者： Shi-mingZheng Zheng-da Huang (department of Mathematics, Xixi Campus, Zhejiang university, Hangzhou 31002.,{2.) 浙江大学浙江杭州 310028

Presents the first estimation conditions for Nourein iterations for simultaneous finding all zeros of a polynomial under which the iteration processes are guaranteed to converge. Computational formulas; Theorems and p... 详细信息

关键词： polynomial zeros parallel iteration Nourein iterations point estimation convergence

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蛇形消毒池模型浓度场试验研究

水力发电学报 2004年第5期23卷 74-77页

作者：王虹彭期冬靳宝华清华大学水利系北京100084

本文采用PLIF(PlanarLaserInducedFluorescence)技术对蛇形消毒池内部的浓度场进行了试验研究。获得了恒定流多种工况下溶质对流扩散初始阶段的非恒定浓度场变化过程 ,以及恒定情况下的场内浓度分布。测量结果表明消毒池在恒定来流和恒... 详细信息

本文采用PLIF(PlanarLaserInducedFluorescence)技术对蛇形消毒池内部的浓度场进行了试验研究。获得了恒定流多种工况下溶质对流扩散初始阶段的非恒定浓度场变化过程 ,以及恒定情况下的场内浓度分布。测量结果表明消毒池在恒定来流和恒定投放消毒剂的情况下 ,出口处水体浓度分布均匀且随时间变化不大 ,这可以充分保证消毒池出来的水体中消毒剂的残留浓度符合要求 ,达到较好的消毒效果。

关键词：环境水利 PLIF 时均浓度浓度脉动

Selected issues at the interface between nuclear physics and astrophysics as well as the standard model

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中国科学：物理学、力学、天文学英文版 2011年第S1期54卷 119-123页

作者： MENG Jie1,2.3, NIU ZhongMing1, LIANG HaoZhao1 & SUN BaoHua2.4 1State Key Laboratory of Nuclear Physics and Technology, School of Physics, Peking university, beijing 100871,{2. 2.chool of Physics and Nuclear Energy Engineering, Beihang university, beijing 100191,{2. 3department of Physics, university of Stellenbosch, Stellenbosch, South Africa 4Justus-Liebig-Universita¨t Giessen, Heinrich-Buff-Ring 14, Giessen 35392. Germany 1. State Key Laboratory of Nuclear Physics and Technology School of Physics Peking University Beijing 100871 China 2. School of Physics and Nuclear Energy Engineering Beihang University Beijing 100191 China 3. department of Physics University of Stellenbosch Stellenbosch South Africa 4. Justus-Liebig-Universit?t Giessen Heinrich-Buff-Ring 14 Giessen 35392 Germany

The density functional theory (DFT) with a minimal number of parameters allows a very successful phenomenological description of ground state properties of nuclei all over the periodic table. The recent developments on the application of the covariant density functional theory as well as its extensions by the group in beijing for a series of interests and hot topics in nuclear astrophysics and nuclear structure are reviewed, including the rapid neutron-capture process, Th/U chronometer, and isospin corrections for superallowed β transitions.

关键词： rapid neutron-capture process nuclear chronometer isospin symmetry-breaking corrections

DECISION TREE COMPLEXITY OF GRAPH PROPERTIES

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中国科学院大学学报 1999年第2期 95-99页

作者： Gao Suixiang (Mathematics department,Graduate School university of Science & Technology of{2.,beijing 100039)

Decision tree complexity is an important measure of computational complexity.A graph property is a set of graphs such that if some graph G is in the set then each isomorphic graph to G is also in the *** P be a graph property on n vertices,if every decision tree algorithm recognizing P must examine at least k pairs of vertices in the worst case,then it is said that the decision tree complexity of P is k .If every decision tree algorithm recognizing P must examine all n(n -1)/2.pairs of vertices in the worst case,then P is said to be elusive .Karp conjectured that every nontrivial monotone graph property is *** this paper,we present some positive results for this *** research the decision tree complexity of graph property in view of algebraic topology and show that if the abstract simplicial complex of a nontrivial monotone graph property P on n vertices has dimension at most n -1( n -2.in another case),then P is elusive

关键词： Computation complexity graph property decision tree algorithm elusive

Uniform asymptotic stability in functional differential equations with infinite delay

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Chinese Science Bulletin 1998年第12期43卷 1000-1003页

作者： XU Anshi department of Mathematics, Sichuan university, Chengdu 610064,{2. department of Mathematics Sichuan University Chengdu China

The fading memory space is used as phace space, and Liapunov methods are used to give conditions ensuring that the zero solution of functional differential equations with infinite delay is uniformly asymptotically sta... 详细信息

关键词： functional differential equation integral-differential equation fading memory space uniform asymptotic stalility.

Diffusion Equation on Fractals:Three-Dimensional Case

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Communications in Nonlinear Science and Numerical Simulation 1999年第3期4卷 3-5页

作者： Qiuhua ZENG and Houqiang LI(department of Physics, Sichuan university, ChengDu 610064,{2.) department of Physics Sichuan University ChengDu 610064 China

IntroductionInrecentyearsthephenomenonofunusualtrajnsport-prop***onindisorderedmediaorfractalmedia,anomalousdiffusionistheoretic... 详细信息

IntroductionInrecentyearsthephenomenonofunusualtrajnsport-prop***onindisorderedmediaorfractalmedia,anomalousdiffusionistheoretic...

关键词： comb model probability density diffusion on fractals

Multi-objective dynamic detection of seeds based on machine vision

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Progress in Natural Science:Materials International 2007年第2期17卷 217-221页

作者： XUN Yi, ZHANG Junxiong, LI Wei and CAI Weiguo ( College of Engineering, china Agricultural university, {2. 100083, china College of Science, Dalian Fisheries university, Dalian 11602., china) [a]College of Engineering China Agricultural University Beijing China [b]College of Science Dalian Fisheriers University Dalian China

An approach to inspecting massive numbers of moving seeds was studied based on the techniques of dynamic inspection and machine vision. A progressive scanning CCD camera with external trigger function was used for real-time capture of dynamic images of seeds. The methods based on R channel of RGB (Red, Green and Blue) and region-dependent segmentation were adopted to reduce the data size of image processing and improve the efficiency of seeds inspection. All the seeds were sorted into four grades according to their morphological characteristics, such as surface area, perimeter, major axis, minor axis, circularity and eccentricity. The detection experiments indicated that the eligible ratio of the classifications was about 81.90% by this real-time inspection system.

关键词： machine vision seed sorting multi-objective morphological parameter.

Dynamic recrystallization during hot torsion of Al-4Mg alloy

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Journal of university of Science and Technology beijing 2003年第2期10卷 45-48页

作者： Junpin Lin, Yanli Wang, Zhi Lin, and Guoliang ChenState Key Laboratory of Advanced Metal Materials, university of Science and Technology beijing, beijing 100083, china Lab. of Adv. Metal Mat. Univ. of Sci. and Technol. Beijing Beijing 100083 China

Binary Al-4Mg alloy have been deformed by hot torsion at 300-500 deg C andstrain rates of 0.006-1.587 s^(-1) to a true strain of 5.5. The specimens were annealed in vacuumfor 1.5 h at 500 deg C and then water quenched. The study indicates that the dynamicrecrystallization occurs during hot torsion of Al-4Mg alloy in a certain range of Z parameter(Zener-Hollmon Parameter), i.e. 19.3 2..8. Increasing the strain rate at higher deformationtemperature or reducing the strain rate at lower deformation temperature accelerates the occurrenceof dynamic recrystallization in the alloy.

关键词： Al-4Mg alloy dynamic recrystallization hot torsion