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A MONOTONE COMPACT IMPLICIT SCHEME FOR NONLINEAR REACTION-DIFFUSION EQUATIONS

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Journal of Computational Mathematics 2008年第2期26卷 123-148页

作者： Yuanming Wang Department of Mathematics,east china Normal university,{3. 200241,china Division of Computational science,E-Institute of {3. Universities,{3. Normal Benyu Guo Department of Mathematics,{3. Normal university,{3. 20023.,china Division of Computational science,E-Institute of {3. Universities,{3.,china Department of Mathematics East China Normal University Shanghai 200241 China Division of Computational science E-Institute of Shanghai Universities Shanghai Normal University Shanghai 200234 China Department of Mathematics Shanghai Normal University Shanghai 200234 China Division of Computational science E-Institute of Shanghai Universities Shanghai China

A monotone compact implicit finite difference scheme with fourth-order accuracy in space and second-order in time is proposed for solving nonlinear reaction-diffusion equations. An accelerated monotone iterative method for the resulting discrete problem is presented. The sequence of iteration converges monotonically to the unique solution of the discrete problem, and the convergence rate is either quadratic or nearly quadratic, depending on the property of the nonlinear reaction. The numerical results illustrate the high accuracy of the proposed scheme and the rapid convergence rate *** iteration.

关键词： Nonlinear reaction-diffusion equation Monotone compact implicit scheme High accuracy Monotone iteration Rapid convergence rate.

Smoothness for the collision local times of bifractional Brownian motions

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science china Mathematics 2011年第9期54卷 1859-1873页

作者： SHEN GuangJun 1,2,& YAN LiTan 3.1 Department of Mathematics,east china university of {3. and technology,shanghai 20023.,china 2 Department of Mathematics,Anhui Normal university,Wuhu 241000,china 3.Department of Mathematics,Donghua university,shanghai 201620,china Department of Mathematics East China University of Science and Technology Department of Mathematics Anhui Normal University Department of Mathematics Donghua University

Let B^Hi,Ki ={ Bt^Hi,Ki, t ≥ 0}, i= 1, 2 be two independent bifractional Brownian motions with respective indices Hi ∈ （0, 1） and K∈ E （0, 1]. One of the main motivations of this paper is to investigate f0^Tδ（Bs^H1 ,K1 - the smoothness of the collision local time, introduced by Jiang and Wang in 2009, IT = f0^T δ（Bs^H1,K1）ds, T 〉 0, where 6 denotes the Dirac delta function. By an elementary method, we show that iT is smooth in the sense of the Meyer-Watanabe if and only if min{H-1K1, H2K2} 〈-1/3.

关键词： bifractional Brownian motion collision local time intersection local time chaos expansion

Experimental Study of Energy-Saving Air-Conditioner with Hot Water

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湖南大学学报（自然科学版） 2009年第S1期36卷 75-78页

作者： CHEN Jian-bo,CHEN Dan,LU Ying(university of shanghai for science and {3.,shanghai,china) university of shanghai for science and {3. Shanghai 200000 China

Energy-saving air-conditioner with hot water is an air source heat pump air-conditioner,which can also supply hot *** hot water is heated by a double pipe condenser connected with an air-cooled condenser in series in the *** experiment of the energy-saving air-conditioner was carried out in the enthalpy-difference air-conditioner *** hot water temperature and the compressor's discharge and suction pressure were recorded in the working condition,where the ambient temperature was at 43.℃,3. ℃,21 ℃,7 ℃,and 2 ℃ *** results showed that the system operated stably and *** system can supply 240 L hot water at 50 ℃ in the whole year,and its coefficience of performance(COP)is much higher than the conventional air source heat pump *** energy conservation was proved by comparing the thermal efficiency with other sourece water heaters.

关键词： air-conditioning water heaters energy conservation heat pump systems thermal efficiency

Impact chaos control and stress release——A key for development of ultra fine vibration milling

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Progress in Natural science:Materials International 2002年第5期12卷 18-23页

作者： WANG Shulin(Department of Power Engineering, university of shanghai for science and {3., shanghai 200093. china) shanghai Univ Sci & Technol Dept Power Engn Shanghai 200093 Peoples R China

Through our previous experimental and analytical studies, it has been discovered that the key for the development of vibration milling is the impact chaos control and stress release. The necessities for the chaos control and stress release are: (i) to strictly e-liminate the sub-harmonics; (ii) to control the super-harmonics to a lower level and (iii) to load the system compressively with relatively higher period, in order that the vibration energy can be absorbed by the particles effectively and sufficiently. A new vibration model for ultra fine milling is proposed, which has wide applications in preparing ultra fine particles.

关键词： vibration mills ultra fine milling impact chaos control stress release.

Seamlet carving for shape-aware image resizing

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science china(Information sciences) 2012年第5期55卷 1073-1081页

作者： LIN Xiao 1,2,SHENG Bin 1,MA LiZhuang 1,SHEN Yang 1 & CHEN ZhiHua 3.1 Department of Computer science and Engineering,shanghai Jiao Tong university,shanghai 200240,china 2 Academy of Information technology,Luoyang Normal university,Luoyang 471022,china 3.Department of Computer science and Engineering,east china university of science and technology,shanghai 20023.,china Department of Computer science and Engineering Shanghai Jiao Tong University Academy of Information technology Luoyang Normal University

In this paper we propose an optimized seam-carving approach for anti-shearing image *** image/video seam-carving strategy only focuses on deleting the pixels along 8-connected seams,which may lead to the obvious information loss during *** the traditional seam-carving methods,our approach can construct a seamlet to handle the discontinuous pixels and further achieve an optimized image resizing results with *** particular,to suppress zigzag artifacts,we introduce the anti-shearing energy into the seamlet generation,which includes two steps:1) the energy map is formalized by using Gabor filtering and the saliency map;2) The energy computation is optimized in Gabor feature space to obtain the resizing results without the connectivity *** experimental results and comparisons show the effectiveness of our method.

关键词： image resizing seamlet carving saliency map

Lie bialgebras of generalized Witt type

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science china Mathematics 2006年第4期49卷 533-544页

作者： SONG Guang’ai & SU Yucai College of Mathematics and Information science, Shandong Institute of Business and technology, Yantai 264005, china Department of Mathematics, {3. of science and technology of china, Hefei 23.026, china Department of Mathematics, shanghai Jiaotong {3., shanghai 200240, china College of Mathematics and Information science Shandong Institute of Business and Technology Yantai China Department of Mathematics Shanghai Jiaotong University Shanghai China Department of Mathematics University of Science and Technology of China Hefei China

In this paper, all Lie bialgebra structures on the Lie algebras of generalized Witt type are considered. It is proved that, for any Lie algebra W of generalized Witt type, all Lie bialgebras on W are the coboundary triangular Lie bialgebras. As a by-product, it is also proved that the first cohomology group H1(W, W(?)W) is trivial.

关键词： Lie bialgebras, Yang-Baxter equation, Lie algebra of generalized Witt type.

Study on Activated Bentonite Applied to tert-Butylation of Toluene

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china Petroleum Processing & Petrochemical technology 2011年第1期13卷 38-44页

作者： Chen Linbo Shi Li (Department of Petroleum Processing,east china university of {3. and technology,shanghai 20023.) Department of Petroleum Processing East China University of Science and Technology Shanghai 200237 China

tert-Butylation of toluene with tert-butanol used as the alkylating agent was investigated over the activated bentonite and HY zeolite used as the *** influences of various butylation reaction parameters,including the toluene/tert-butanol ratio,the reaction temperature,and the space velocity were *** optimal results were obtained at a reaction temperature of 180 ℃,a space velocity of 4 h-1,and a mole ratio of toluene to tert-butanol equating to *** structure and acidic properties of catalyst were characterized by the BET method and the Fourier transform infrared (FTIR) *** with the HY zeolite,the activated bentonite possessed high activity for toluene conversion and high para-selectivity because it had larger pore diameter,smaller micropore surface area and higher ratio of total Lewis acids to total Br nsted acids.

关键词： t-butylation activated bentonite p-tert-butyltoluene pore diameter Lewis acid

A NOTE ON THE DIPERNA-LIONS FLOWS

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Acta Mathematica Scientia 2011年第5期31卷 1719-1724页

作者：刘昕黄文亮 School of Computer science and technology Huazhong University of Science and Technology Department of Mathematics East China University of Science and Technology

In this note, we give a short proof for the DiPerna-Lions flows associated to ODEs following the method of Crippa and De Lellis [3.. More precisely, assume that [divb] ∈ Ll∞oc（Rd）, ｜b｜/（1 ＋｜x｜ log ｜x｜） ∈ L∞（Rd） and ｜ b｜ φ（｜ b｜） ∈ Ll1oc（Rd）, where φ（r） = log log（r ＋ c）, c 0. Then, there exists a unique regular Lagrangian flow associated with the ODE X˙（t, x） = b（X（t, x））, X（0, x） = x.

关键词： DiPerna-Lions flow Hardy-Littlewood maximal function

Tissue P systems with parallel rules on channels

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Progress in Natural science:Materials International 2007年第4期17卷 486-491页

作者： Xu Xian (Department of Computer science and technology, shanghai Jiao Tong {3., shanghai 200240, china) Department of Computer science and technology Shanghai Jiao Tong University Shanghai 200240 China

A new variant of P systems as an improvement of the original design is introduced. The P systems here allow parallelism in rules application on synapses (or links, channels), rendering the systems more efficient. We describe the execution mechanism of our P systems, make analysis on its computation power, and illustrate the running by an example.

关键词： tissue P systems parallel rules.