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Development and application of ergodicity model with FrCM and FLAr for hydrological process

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Science china(Technological sciences) 2009年第2期52卷 379-386页

作者： WANG Hongrui1, FENG QiLei2, LIN Xin3 & ZENG WenYi4 1 College of Water Science, Key Laboratory for Water and Sediment sciences of the Ministry of Education, Beijing Normal University, Beijing 100875, china 2 school of Science, Beijing Institute of Education, Beijing 100011, china 3 school of mathematical sciences, Beijing Normal University, Beijing 100875, china 4 College of Information Science and technology, Beijing Normal University, Beijing 100875, china 1. College of Water Science Key Laboratory for Water and Sediment Sciences of the Ministry of Education Beijing Normal University Beijing 100875 China 2. school of Science Beijing Institute of Education Beijing 100011 China 3. school of mathematical sciences Beijing Normal University Beijing 100875 China 4. College of Information Science and technology Beijing Normal University Beijing 100875 China

In this paper, a new ergodic property analysis model of hydrological process is proposed based on fuzzy-rough c-means clustering (FrCM), autocorrelogram, and fuzzy least absolute regression (FLAr). A precipitation time series (1951―2004) from Shanghai Hydrology Station is then analyzed with the model. The results show that the precipitation time series of April, May, June, and September has er-godic property. We conclude that in the long run, the precipitation of April, May, June, and September will not keep decreasing; it will converge to its mean value in some period.

关键词： hydrological process ergodic autocorrelogram fuzzy-rough c-means clustering fuzzy least absolute regression

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, Beijing 100190, china 3 Institute of Space physics and Applied technology, peking University, Beijing 100871, china 4 CAS Key Lab for Basic plasma Science, school of Earth and Space sciences, University of Science and technology of china, Hefei 230026, 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

The relative generalized Hamming weight and the semilinear equivalence of codes

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Science china(Information sciences) 2011年第4期54卷 787-794页

作者： LIU ZiHui 1 & WANG Jie 2 1 Department of Mathematics,Beijing Institute of technology,Beijing 100081,china 2 school of mathematical sciences,Beijing University,Beijing 100871,china 1. Department of Mathematics Beijing Institute of Technology Beijing 100081 China2. School of Mathematical Sciences Beijing University Beijing 100871 China

Certain equivalent conditions are given for the semilinear equivalence of linear codes by using the relative generalized Hamming weight and the value function.

关键词： value function semilinear equivalence support weight relative generalized Hamming weight

The Signless Laplacian Spectral radius of Tricyclic Graphs with k pendant Vertices

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Journal of mathematical research with Applications 2012年第3期32卷 281-287页

作者： Jingming ZHANG1,2,Jiming GUO 2 1.school of mathematical sciences,University of Electronic Science and technology of china, Sichuan 611731,p.r.china 2.College of Mathematics and Computational Science,china University of petroleum, Shandong 257061,p.r.china school of mathematical sciences University of Electronic Science and Technology of China College of Mathematics and Computational Science China University of Petroleum

In this paper,we determine the unique graph with the largest signless Laplacian spectral radius among all the tricyclic graphs with n vertices and k pendant vertices.

关键词： signless Laplacian spectral radius tricyclic graph pendant vertex.

Effects of salinity on methane gas hydrate system

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Science china Earth sciences 2007年第11期50卷 1733-1745页

作者： YANG DingHui1 & XU WenYue2 1 Department of mathematical sciences, Tsinghua University, Beijing 100084, china 2 school of Earth & Atmospheric sciences, Georgia Institute of technology, Atlanta, GA 30332, USA 1. Department of mathematical sciences Tsinghua University Beijing 100084 China 2. school of Earth & Atmospheric sciences Georgia Institute of Technology Atlanta GA 30332 USA

Using an approximately analytical formation, we extend the steady state model of the pure methane hydrate system to include the salinity based on the dynamic model of the methane hydrate system. The top and bottom boundaries of the methane hydrate stability zone (MHSZ) and the actual methane hy-drate zone (MHZ), and the top of free gas occurrence are determined by using numerical methods and the new steady state model developed in this paper. Numerical results show that the MHZ thickness becomes thinner with increasing the salinity, and the stability is lowered and the base of the MHSZ is shifted toward the seafloor in the presence of salts. As a result, the thickness of actual hydrate occur-rence becomes thinner compared with that of the pure water case. On the other hand, since lower solubility reduces the amount of gas needed to form methane hydrate, the existence of salts in sea-water can actually promote methane gas hydrate formation in the hydrate stability zone. Numerical modeling also demonstrates that for the salt-water case the presence of methane within the field of methane hydrate stability is not sufficient to ensure the occurrence of gas hydrate, which can only form when the methane concentration dissolved in solution with salts exceeds the local methane solubility in salt water and if the methane flux exceeds a critical value corresponding to the rate of diffusive methane transport. In order to maintain gas hydrate or to form methane gas hydrate in marine sedi-ments, a persistent supplied methane probably from biogenic or thermogenic processes, is required to overcome losses due to diffusion and advection.

关键词： methane gas hydrate,solubility,stability of hydrate,salinity,phase equilibrium

Ameliorative Effects of Brassinosteroid on Excess Manganese-Induced Oxidative Stress in Zea mays L. Leaves

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Agricultural sciences in china 2009年第9期8卷 1063-1074页

作者： WANG Hai-hua, FENG Tao, pENG Xi-xu, YAN Ming-li, ZHOU ping-lan and TANG Xin-ke school of Life sciences, Hunan University of Science and technology, Xiangtan 411201, p.r.china [a]school of Life sciences Hunan University of Science and Technology Xiangtan 411201 P.R.China

Manganese （Mn） is becoming an important factor limiting crop growth and yields especially on acid soils. The present study was designed to explore the hypothesis that brassinosteroid application can enhance the tolerance of maize （Zea mays L.） to Mn stress and if so, whether or not the mechanism underlying involves regulation of antioxidative metabolism in leaves. The effects of 24-epibrassinosteroid （EBr） on the growth, photosynthesis, water status, lipid peroxidation, accumulation of reactive oxygen species, and activities or contents of antioxidant defense system in maize plants under Mn stress were investigated by a pot experiment. At supplemented Mn concentrations of 150-750 mg kg^-1 soil, the growth of plants was inhibited in a concentration-dependent manner. The semi-lethal concentration was 550 mg Mn kgq soil. Foliage application with 0.1 mg L^-1 EBr significantly reduced the decrease in dry mass, chlorophyll content, photosynthetic rate, leaf water content, and water potential of plants grown in the soil spiked with 550 mg kg^-1 Mn. The oxidative stress caused by excess Mn, as reflected by the increase in malondialdehyde （MDA） content and lipoxygenase （LOX, EC 1.***.11.12） activity, accumulation of superoxide radical and H2O2, was greatly decreased by EBr treatment. Further investigations revealed that EBr application enhanced the activities of superoxide dismutase （SOD, EC 1.***.1.1）, peroxidase （pOD, EC 1.***.1.7）, catalase （EC 1.***.1.6）, ascorbate peroxidase （ApX, EC 1.11. 1.11）, dehydroascorbate reductase （DHAr, EC 1.***.5.1）, and glutathione reductase （Gr, EC 1.***.4.2）, and the contents of reduced ascorbate and glutathione, compared with the plants without EBr treatment. It is concluded that the ameliorative effects of EBr on Mn toxicity are due to the upregulation of antioxidative capacity in maize under Mn stress.

关键词： excess manganese brassinosteroid oxidative stress antioxidant defense system maize (Zea mays L.)

Boundedness for commutators of fractional Hardy operators on Herz spaces

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progress in Natural Science:Materials International 2007年第1期17卷 20-25页

作者： FU Zunwei, LIU Zongguang and LU Shanzhen ( school of mathematical sciences, Beijing Normal University, Beijing 100875, china Department of Mathematics, Linyi Normal University, Linyi 276005, china Department of Mathematics, china University of Mining and technology, Beijing 100083, china) [a]school of mathematical sciences Beijing Normal University Beijing China [b]Departhent of Mathematics Linyi Normal University Linyi China [c]Departhent of Mathematics China University of Mining and Technology Beijing China

Some boundedness results are established for commutators generated by classical fractional Hardy operators and one-sided CMO functions on the homogeneous Herz spaces, which extends some known results.

关键词： fractional Hardy operator Hardy’s integral inequality commutator one-sided CMO function homogeneous Herz space.

Blow Up of Solutions to Semilinear Wave Equations with Critical Exponent in High Dimensions

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Chinese Annals of Mathematics,Series B 2007年第2期28卷 205-212页

作者： Yi ZHOU school of mathematical sciences Fudan University Shanghai 200433 China

In this paper, the author considers equations with critical exponent in n ≥4 space tions on the initial data, it is proved that there small the initial data are. the Cauchy problem for semilinear wave dimensions. Und... 详细信息

关键词： Semilinear wave equation Critical exponent Cauchy problem Blow up

Image denoising and deblurring: non-convex regularization, inverse diffusion and shock filter

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Science china(Information sciences) 2011年第6期54卷 1184-1198页

作者： FU ShuJun 1,2,3 , ZHANG CaiMing 2 & TAI XueCheng 3,4 1 school of Mathematics, Shandong University, Jinan 250100, china 2 school of Computer Science and technology, Shandong University, Jinan 250101, china 3 school of physical and mathematical sciences, Nanyang Technological University, Singapore 639798, Singapore 4 Department of Mathematics, University of Bergen, Bergen 5008, Norway 1. school of Mathematics Shandong University Jinan 250100 China2. School of Computer Science and Technology Shandong University Jinan 250101 China3. School of Physical and Mathematical Sciences Nanyang Technological University Singapore 639798 Singapore4. Department of Mathematics University of Bergen Bergen 5008 Norway

A large number of applications in image processing and computer vision depend on image quality. In this paper, main concerns are image denoising and deblurring simultaneously in a restoration task by three types of methodologies: non-convex regularization, inverse diffusion and shock filter. We discuss their relations in the context of image deblurring: the inverse diffusion implied by the non-convex regularization, and the superior ability of deblurring edge of the shock filter to that of the inverse diffusion, both in 1D and 2D cases. Finally, we propose a region-based adaptive anisotropic diffusion with shock filter method, which shows advantages of deblurring edges, denoising and smoothing contours in experiments, compared with some related methods. Therein an idea of "divide and rule" is introduced.

关键词： image denoising image deblurring non-convex regularization inverse diffusion shock filter adaptive anisotropic diffusion