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A NOTE ON THE RELATIVE CANONICAL IMAGE OF A NON-HYPERELLIPTIC FIBRATION OF GENUS

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Chinese Annals of mathematics,Series B 1994年第2期15卷 157-164页

作者： CHEN ZHIJIE(department of Matehematics,east normal university, shanghai 00062, china) E china normal UNIV DEPT MATHSHANGHAI 200062PEOPLES R CHINA

This paper investigates the relative 1-canonical images of non-hyperelliptic fibrations of genus 4. It is proved that if a fibre of the relative 1-canonical image ∑ is not a complete intersection in 3 , then the var... 详细信息

关键词： Genus Non-hyperelliptic fibration Canonical image Algebraic variety.

THE GPL-STABILITY OF RUNGE-KUTTA METHODS FORDELAY DIFFERENTIAL SYSTEMS

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Journal of Computational mathematics 2000年第1期18卷 75-82页

作者： Biao Yang Lin Qiu Jiao-xun Kuang(department of mathematics, shanghai normal university, shanghai 200234, china.) 上海师范大学上海 200234

Presents a study which dealt with stability of the implicit Runge-Kutta methods for the numerical solutions of the systems of delay differential equations. Stability behavior of the methods; Exponential solutions of t... 详细信息

关键词： delay differential equation implicit Runge-Kutta methods GPL-stability

Denitrification in Chongming east tidal flat sediment, Yangtze estuary, china

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Science china Earth Sciences 2006年第10期49卷 1090-1097页

作者： WANG Dongqi1,2, CHEN Zhenlou1,3, XU Shiyuan1,2, HU Lingzhen1 & WANG Jun1,2 1. College of Resources & Environment, east china normal university, shanghai 200062, china 2. State Key Laboratory of Estuarine and Coastal Sediment Dynamics and Morphodynamics, east china normal university, shanghai 200062, china 3. Key Laboratory of Geographical Information Science of Ministry of Education,east china normal university,shanghai 200062, china 1. College of Resources & Environment East China Normal University Shanghai 200062 China 2. State Key Laboratory of Estuarine and Coastal Sediment Dynamics and Morphodynamics East China Normal University Shanghai 200062 China 3. Key Laboratory of Geographical Information Science of Ministry of Education East China Normal University Shanghai 200062 China

From July 2003 to July 2004, samples were collected on Chongming Island east tidal flat every two months. The research showed that the nitrous oxide (N2O) production rate was very low in the water, Chongming east tidal flat (CM) sediment was the N2O source of the water. Sediment N2O natural production rate was between -0.08 and 1.74 μmolN·m-2·h-1. N2O natural production rate was higher in the summer. The difference of the N2O natural production rate in the different tidal flats, the correlation between the N2O natural production rate and the denitrification rate, and those with the temperature and DO indicate that middle tidal flat sediment denitrification was the main process of the N2O production, while in the low tidal flat sediment, the production of the N2O came from several processes of the nitrogen cycling. Tidal flat sediment denitrification reaction was stronger in summer and winter but relatively lower in the late autumn and early spring. Seasonal change of the sediment denitrification rate was wide, from 1.12 to 33.34 μmolN·m-2·h-1. Temperature, DO and the coactions of them had the prominent effect on the tidal flat sediment denitrification.

关键词： Yangtze estuary, tidal flat sediment, denitrification, nitrous oxide, effect factor.

Back-scattering from rough sea surface with foams

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Acta Oceanologica Sinica 1993年第4期12卷 563-572页

作者： Jin Yaqiu, Huang Xingzhong and Yin Jieyi department of Electronic Engineering, Fudan university, shanghai 200433, china department of Electronic Science, china east normal university, shanghai 200062, china Dept of Electronic Engineering Fudan University Shanghai 200433 China China

By using iterative method to solve the vector radiative transfer equation of discrete scatterers with randomly rough under-boundary, the back-scattering coefficient is derived, and is applied to the two-scale model of sea surface with foam scatterers driven by strong wind. By employing the modified probability density function of Cox and Munk's, and Pierson's sea spectrum, numerical results of polarized back-scatter ing are calculated. The functional dependence on wind speed and direction, observation angle, polarization and other parameters are discussed, and theoretical results are favorably matched with experimental data.

关键词： Radiative transfer two-scale randomly rough surface back-scattering wind

DEGENERATED HOMOCLINIC BIFURCATIONS WITH HIGHER DIMENSIONS

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Chinese Annals of mathematics,Series B 2000年第2期21卷 201-210页

作者： JINYINLAI ZHUDEMINC departmentofmathematics EastChinaNormalUniversityShanghai200062China. departmentofmathematics LinyiTeacherCollegeLinyi276005ShandongChina.

The degenerated homoclinic bifurcation for high dimensional system is considered. The existence, uniqueness, and incoexistence of the 1-homclinic orbit and 1-periodic orbit near　Г are studied under the nonresonant c... 详细信息

关键词： Local coordinates Poincare map Homoclinic orbit Periodic orbit 2-fold periodic orbit Resonant condition

Cholesterol oxidase biosensor based on a glassy carbon electrode modified with Nafion and methyl viologen

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Chinese Journal of Chemistry 1994年第4期12卷 343-347页

作者： JIN, Li-Tong ZHAO, Gui-Zhu FANG, Yu-Zhidepartment of Chemistry, east china normal university, shanghai 200062, china department of Chemistry East China Normal University Shanghai 200062 China

Cholesterol oxidase biosensor has been constructed by using bovine serum albumin and glutaraldehyde as cross linker to immobilize cholesterol oxidase and cholesterol esterase on a glassy carbon electrode modified with Nafion and methyl viologen. The biosensor has been used to determine total cholesterol in blood. The linear range of the determination is 2.5×10~7 to 1.0×10-4 mol/L. The detection limit is about 5.0×10~8 mol/L. The response time is 12 s. This biosensor has the advantage of high selectivity, sensitivity and short response time.

关键词： Biosensor cholesterol oxidase enzyme electrode.

Harmonic maps with potential from complete manifolds

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Chinese Science Bulletin 1998年第21期43卷 1780-1786页

作者： CHEN Qun mathematics department, Central china normal university, Wuhan 430079, china Institute of mathematics, Fudan university, shanghai 200433, china mathematics department Central China Normal University Wuhan China Institute of mathematics Fudan University Shanghai China

Harmonic maps with potential from complete manifolds are considered. This is a new kind of maps more general than the usual harmonic maps relating to many interesting problems such as equilibrium system of ferromagnetic spin chain and Neumann motion. Aiming at the general properties, the author derives basic gradient estimates and then Liouville type results for these maps, which are interesting in constrast to those of the usual harmonic maps for the presence of potentials.

关键词： harmonic maps potential ferromagnetic chain gradient estimate.

Checking for normality in linear mixed models

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Science china mathematics 2012年第4期55卷 787-804页

作者： WU Ping 1,,ZHU LiXing 2,3 & FANG Yun 4 1 School of Finance and Statistics,east china normal university,shanghai 200241,china 2 School of Statistics and mathematics,Yunnan university of Finance and Economics,Yunnan 650221,china 3 The department of mathematics,Hong Kong Baptist university,Hong Kong 999077,china 4 mathematics and Science College,shanghai normal university,shanghai 200234,china 1. School of Finance and Statistics East China Normal University Shanghai 200241 China2. School of Statistics and Mathematics Yunnan University of Finance and Economics Yunnan 650221 China3. The Department of Mathematics Hong Kong Baptist University Hong Kong 999077 China4. Mathematics and Science College Shanghai Normal University Shanghai 200234 China

Linear mixed models are popularly used to fit continuous longitudinal data, and the random effects are commonly assumed to have normal distribution. However, this assumption needs to be tested so that further analysis can be proceeded well. In this paper, we consider the Baringhaus-Henze-Epps-Pulley （BHEP） tests, which are based on an empirical characteristic function. Differing from their case, we consider the normality checking for the random effects which are unobservable and the test should be based on their predictors. The test is consistent against global alternatives, and is sensitive to the local alternatives converging to the null at a certain rate arbitrarily close to 1/V~ where n is sample size. ^-hlrthermore, to overcome the problem that the limiting null distribution of the test is not tractable, we suggest a new method： use a conditional Monte Carlo test （CMCT） to approximate the null distribution, and then to simulate p-values. The test is compared with existing methods, the power is examined, and several examples are applied to illustrate the usefulness of our test in the analysis of longitudinal data.

关键词： linear mixed models estimated best linear unbiased predictors BHEP tests conditional MonteCarlo test

Spectral Radius of Non-negative Matrices and Digraphs

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Acta Mathematica Sinica,English Series 2002年第2期18卷 293-300页

作者： ZHANG Xiao Dong department of mathematics.east china normal university,shanghai 200062.P.R.china E-mail:xdzhang2@hotmail.comLI Jiong Sheng department of mathematics.university of Science and Technology of china,Hefei 230026,P.R china department of mathematics East China Normal University Shanghai P. R. China department of mathematics University of Science and Technology of China Hefei P. R. China

We present,an upper and a lower bound for the spectral radius of non-negative matrices. Then we give the bounds for the spectral radius of digraphs.

关键词： Non-negative matrix Digraph Spectral radius