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Influence of Acetic Acid on Dynamic Behavior of Hydrolazation and Film Forming of Organosilane

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Journal of wuhan university of Technology(Materials Science) 2009年第4期24卷 546-551页

作者：杨丽霞 School of Materials Chemistry and Engineering China University of Geosciences

The influence of acetic acid on dynamic behavior of hydrolazation and film forming of an expoxy-silane compound （y-GPS） was investigated by conductivity meter, IR and AFM. The experimental results show that there is an optimal pH value（pH=4.5） for hydrolysis of silane solution, and with the prolongation of hydrolytic time, the promotion of acetic acid on the hydrolyzation of silane solution become more obvious. During the adsorption and film forming process, acetic acid could promote the formation of Si-O-Fe bond, which activates hydroxyl group of silanol unit and facilitates this hydroxyl group to react with adjacent silanol unit forming linear condensation polymers.

关键词： organosilane hydrolyzation film forming acetic acid

Seabed Classification Using BP Neural Network Based on GA

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Acta Oceanologica Sinica 2003年第4期22卷 523-531页

作者： Yang Fanlin1, Liu Jingnan2 1. GPS Engineering Research Center, wuhan university, wuhan 4.0079, china. 2. Presidential Secretariat, wuhan university, wuhan 4.0079, china wuhan Univ GPS Engn Res Ctr Wuhan 430079 Peoples R China

Side scan sonar imaging is one of the advanced methods for seabed study. In order to be utilized in other projects, such as ocean engineering, the image needs to be classified according to the distributions of different classes of seabed materials. In this paper, seabed image is classified according to BP neural network, and. Genetic Algorithm is adopted in train network in this paper. The feature vectors are average intensity, six statistics of texture and two dimensions of fractal. It considers not only the spatial correlation between different pixels, but also the terrain coarseness. The texture is denoted by the statistics of the co-occurrence matrix. Double Blanket algorithm is used to calculate dimension. Because a uniform fractal may not be sufficient to describe a seafloor, two dimensions are calculated respectively by the upper blanket and the lower blanket. However, in sonar image, fractal has directivity, i. e. there are different dimensions in different direction. Dimensions are different in acrosstrack and alongtrack, so the average of four directions is used to solve this problem. Finally, the real data verify the algorithm. In this paper, one hidden layer including six nodes is adopted. The BP network is rapidly and accurately convergent through GA. Correct classification rate is 92.5 % in the result.

关键词： BP network co-occurrence matrix fractal classification genetic algorithin

A. S. Convergence of Two-Parameter Banach Space Valued Martingales and the Radon-Nikodym Property of Banach Spaces

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Acta Mathematica Sinica,English Series 1999年第2期15卷 187-196页

作者： Shixin Gan, Department of Mathematics, wuhan university, wuhan 4.0072, P. R. china Department of Mathematics Wuhan University Wuhan P. R. China

In this paper, we prove that under the F4.condition, any L log+ L bounded two-parameter Banach space valued martingale converges almost surely to an integrable Banach space valued random variable if and only if the Ba... 详细信息

In this paper, we prove that under the F4./sub> condition, any L log+ L bounded two-parameter Banach space valued martingale converges almost surely to an integrable Banach space valued random variable if and only if the Banach space has the Radon-Nikodym property. We further prove that the above conclusion remains true if the F4./sub> condition is replaced by the weaker local F4./sub> condition.

关键词： Two-parameter Banach space valued martingale A. S. convergence Radon-Nikodym property F4.condition Local F4.condition

FRACTAL GEOMETRY STUDY OF CORRELATION BETWEEN IMPACT TOUGHNESS OF STEEL AND PARAMETERS OF FREE-CUTTING PHASE

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Acta Metallurgica Sinica(English Letters) 1992年第4期5卷 250-255页

作者： JIANG Laizhu CUI Kun Huazhong university of Science and Technology,wuhan,china Huazhong Univ of Science and Technology Wuhan China

Studies were made of the calculation of fractal dimension of transverse impact fracture sur- face,and of the correlation between impact toughness of steel and parameters of free-cutting phase by means of the developed fractal geometry model of crack *** is believed that the area fraction,f,of free-cutting phase is negligibly influential to the longitudinal im- pact toughness,as f1 .While the aspect ratio,saying ratio of length to width,of free-cut. ting phase is inversely influential to the transverse impact *** may .be the reason why the transverse impact toughness of free-cutting steel containing more rare earth contrast to sulphur is even higher than the low sulphur containing steel.

关键词： fractal geometry impact toughness free-cutting phase

A Characterization for the Gevrey-Sobolev Wave Front Set

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Acta Mathematica Sinica,English Series 2001年第2期17卷 295-300页

作者： Hua CHEN Institute of Mathematics, wuhan university, wuhan 4.0072, P. R. china Institute of Mathematics Wuhan University Wuhan 430072 P. R. China

In this note, we use the so-called microlocal energy method to give a characterization of the Gevrey-Sobolev wave front set WF(HT,σS （u）, which will be useful in the study of non-linear microlocal analysis in Gevre... 详细信息

关键词： Gevrey-Sobolev space Wave front set Microlocal energy method

Joint enhancement of lead accumulation in Brassica plants by EDTA and ammonium sulfate in sand culture

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Journal of Environmental Sciences 2002年第2期14卷 216-220页

作者： XIONG Zhi\|ting, LU Ping (Department of Environmental Sciences, wuhan university, wuhan 4.0072, china. Department of Environmental Sciences Wuhan University Wuhan 430072 Chin

When EDTA was added alone in the Pb\|contaminated sand, the plant biomass and the total Pb amount in plant decreased in both species, Brassica pekinensis and B. juncea var. multiceps, though the shoot Pb amount increased. In contrast, when (NH 4. 2SO 4.was added alone in the Pb\|contaminated sand, little effect was observed on the shoot Pb amount, though the root Pb amount was significantly increased in B. juncea var. multiceps. When amending EDTA and (NH 4. 2SO 4.in combination, however, the shoot Pb amount in both species substantially increased, being, on an average, 2 times and 9 times higher than that in EDTA alone or (NH 4. 2SO 4.alone amended treatment, respectively. The two amendments showed antagonism for plant growth, but synergism for Pb bioaccumulation. B. pekinensis showed its highest level of shoot and total Pb amount in the treatment amended with EDTA and (NH 4. 2SO 4. only a half as much as in the other treatments. It is inferred that the mechanisms responsible for the joint\|enhanced Pb accumulation might be concerned with the acidification of the growth medium, cation exchange reaction and relieving EDTA induced toxicity as results by amending ammonium sulfate.

关键词： lead bioaccumulation EDTA ammonium sulfate Brassica

ON THE METHOD OF SOLUTION FOR A KIND OFNONLINEAR SINGULAR INTEGRAL EQUATION

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Acta Mathematica Scientia 2004年第3期24卷 507-512页

作者： LuJianke DepartmentofMathematics WuhanUniversityWuhan430072China

The solutions of the nonlinear singular integral equation , t 6 L, are considered, where L is a closed contour in the complex plane, b ≠ 0 is a constant and f(t) is a polynomial. It is an extension of the results obt... 详细信息

关键词： Singular integral equation with Cauchy kernel Riemann boundary value problem with square roots modified principal part Plemelj formula

A Feedback-Based Web Search Engine

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wuhan university Journal of Natural Sciences 2004年第5期9卷 561-568页

作者： ZHANG Wei-feng 1,2,3 , XU Bao-wen 2,3,4., ZHOU Xiao-yu 2,3,4.1. Department of Computer Science and Engineering, Nanjing university of Posts and Telecommunications, Nanjing 210003, Jiangsu, china 2. Department of Computer Science and Engineering, Southeast university, Nanjing 210096, Jiangsu, china 3. Jiangsu Institute of Software Quality, Nanjing 210096 Jiangsu, china 4. The State Key Laboratory of Software Engineering, wuhan university, wuhan 4.0072, Hubei, china Department of Computer Science and Engineering Nanjing University of Posts and Telecommunications . Nanjing 210003 Jiangsu China

Web search engines are very useful information service tools in the Internet. The current web search engines produce search results relating to the search terms and the actual information collected by them. Since the selections of the search results cannot affect the future ones, they may not cover most people’s interests. In this paper, feedback information produced by the user’s accessing lists will be represented by the rough set and can reconstruct the query string and influence the search results. And thus the search engines can provide self-adaptability. Key words WWW - search engine - query reconstruction - feedback CLC number TP 311. 135.4.Foundation item: Supported by the National Natural Science Fundation of china (60373066). National Grand Fundamental Research 973 Program of china (2002CB31200). Opening Foundation of State Key Laboratory of Software Engineering in wuhan university, Opening Foundation of Jiangsu Key Laboratory of Computer Information Processing Technology in Soochow universityBiography: ZHANG Wei-feng (1975-), male, Ph.D. research direction: artificial intelligence, search engine, data mining, network language.

关键词： WWW search engine query reconstruction feedback

Multispectral image fusion method based on intensity-hue-saturation and nonsubsampled three-channels non-separable wavelets

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Chinese Optics Letters 2010年第4期8卷 384-387页

作者：刘斌刘维杰彭嘉雄 School of Mathematics and Computer Science Hubei university Computer School Wuhan University Institute of Image Recognition and Artificial Intelligence Huazhong University of Science and Technology

A new multispectral image fusion method based on intensity-hue-saturation（IHS） transform and threechannel non-separable wavelets whose dilation matrix is[2,1;1,1]is *** multi-resolution decompositions of the intensity of multispectral image and panchromatic image are performed in nonsubsampled mode using the three-channel non-separable wavelet filter *** approximation images and the detail images of the multi-resolution pyramids are *** experimental results show that this method has good visual *** performance outperforms the IHS fusion *** discrete wavelet transform （DWT） fusion method,and the IHS-DWT fusion method in preserving spectral quality and high spatial resolution information.

关键词： Decomposition Discrete wavelet transforms Filter banks Visual communication