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Relationship between bioaccumulation，distribution of MET and lipid content of aquatic organisms

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Journal of Environmental Sciences 1995年第2期7卷 212-217页

作者： Liu Zhengtao Zhou Fengfan Jin Hongjun(Department of Environmental Sciences , nanjing university , nanjing 210093 , China) Dept of Envmtl Sciences Nanjing University Nanjing China China

Ｒｅｌａｔｉｏｎｓｈｉｐｂｅｔｗｅｅｎｂｉｏａｃｃｕｍｕｌａｔｉｏｎ，ｄｉｓｔｒｉｂｕｔｉｏｎｏｆＭＥＴａｎｄｌｉｐｉｄｃｏｎｔｅｎｔｏｆａｑｕａｔｉｃｏｒｇａｎｉｓｍｓＬｉｕＺｈｅｎｇｔａｏ；ＺｈｏｕＦｅｎｇｆａｎ... 详细信息

Ｒｅｌａｔｉｏｎｓｈｉｐｂｅｔｗｅｅｎｂｉｏａｃｃｕｍｕｌａｔｉｏｎ，ｄｉｓｔｒｉｂｕｔｉｏｎｏｆＭＥＴａｎｄｌｉｐｉｄｃｏｎｔｅｎｔｏｆａｑｕａｔｉｃｏｒｇａｎｉｓｍｓＬｉｕＺｈｅｎｇｔａｏ；ＺｈｏｕＦｅｎｇｆａｎ；ＪｉｎＨｏｎｇｊｕｎ（Ｄｅｐａｒ...

关键词： MET bioaccumulation distribution acute toxicity : lipid content.

A MODIFIED CONJUGATE DIRECTION METHOD FOR COMPUTING THE PSEUDOINVERSF

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Journal of Computational Mathematics 1994年第2期12卷 185-194页

作者： Zhao Jin-xi (Dept. of Math., nanjing university, nanjing,China) 南京大学数学系江苏南京

In this paper we are concerned with the modified conjugate direction method for computing the pseudoinverse by using an orthogonal basis of the range space of A. Numerical results show that the new method retains some... 详细信息

关键词： A MODIFIED CONJUGATE DIRECTION METHOD FOR COMPUTING THE PSEUDOINVERSF ATA

IBN Rings and Orderings on Grothendieck Groups

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Acta Mathematica Sinica,English Series 1994年第3期10卷 225-230页

作者： Tong Wenting Department of Mathematics nanjing university nanjing,210008 China Department of Mathematics Nanjing University Nanjing China

Let R be a ring with an identity element.R∈IBN means that Rm■Rn implies m=n,R ∈IBN1 means that Rm ■Rn⊕K implies m≥n,and R ∈IBN2 means that Rm■Rm⊕K implies K=*** this paper we give some characteristic properties of IBN1 and IBN2,with orderings o the Grothendieck *** addition,we obtain the following results:（1）If R ∈IBM1 and all finitely generated projective left R-modules are stably free,then the Grothendieck group Ko（R）is a totally ordered abelian group.（2）If the pre-ordering of the Grothendieck group Ko（R）of a ring R is a partial ordering,then R ∈IBM1 or Ko（R）=0.

关键词： IBN Rings and Orderings on Grothendieck Groups Math PSF

Karst conduit flow and its hydrodynamic characteristics——Houzhai River drainage basin in Fueling,Guizhou,China as an example

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Chinese Science Bulletin 2001年第S1期46卷 45-51页

作者： WANG Lachun & ZHANG YongzhanDepartment, of Urban & Resource Sciences, nanjing university, nanjing 210093, China Key Laboratory of Coast & Island Development of Ministry of Education of China, nanjing university, nanjing 210093, China Department of Urban & Resource Sciences Nanjing University Nanjing China Key Laboratory of Coast & Island Development of Ministry of Education of China Nanjing University Nanjing China

Conduit flow is a special geomorphologic and hydrological phenomenon in karst area. Houzhai River drainage basin in Puding, Guizhou Province is a large-scale test field in the main and broad karst area in the southern part of China, where conduit flow is a general reserve and drainage system for groundwater. Based on the great deal of field investigation and indoor research work during the 1970s-1980s, pulse tests were done four times there during 1988-1991 in wet and dry seasons. It shows that water level at each observation site changes from 10 to 1800 mm, with the larger variation in upper stream and at karst windows than in lower reaches and at each exit along subterraneous rivers. The average flow velocity in conduit system is determined within 200-800 m/h, with the less change from flood to dry seasons, and it is higher in principal conduits and in upper stream area. Also, the reliable divided discharge ratio among each hydrological conduit of sunken system has been got. Thus, combined with

关键词： conduit flow karst pulse test Houzhai River.

On the variational principle for the topological pressure for certain non-compact sets

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Science China Mathematics 2010年第4期53卷 1117-1128页

作者： PEI Yu 1 & CHEN ErCai 1,2,1 Department of Mathematics,nanjing Normal university,nanjing 210097,China 2 Center for Nonlinear Science,nanjing university,nanjing 210093,China Department of Mathematics Nanjing Normal University Center for Nonlinear Science Nanjing University

Let (X,d,T) be a dynamical system,where (X,d) is a compact metric space and T:X → X is a continuous *** assume that the dynamical system satisfies g-almost product property and the uniform separation *** compute the topological pressure of saturated sets under these two *** the uniform separation property does not hold,we compute the topological pressure of the set of generic *** give an application of these results to multifractal analysis and finally get a conditional variational principle.

关键词： uniform separation property g-almost product property topological pressure of non-compact sets variational principle BS-dinmension

Velocity Space of Galactic O-B Stars

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Chinese Journal of Astronomy and Astrophysics 2006年第3期6卷 363-371页

作者： Zi Zhu Department of Astronomy Nanjing University Nanjing 210093

Based on the Hipparcos proper motions and available radial velocity data of O-B stars, we have re-examined the local kinematical structure of the young disk population of 1500 O-B stars not including the Gould-belt stars. A systematic warping motion of the stars about the direction to the Galactic center has been reconfirmed. A negative K-term implying a systematic contraction of stars in the solar vicinity has been detected. Two different distance scales are used in order to find out their impact on the kinematical parameters, and we conclude that the adopted distance scale plays an important role in characterizing the kinematical parameters at the present level of the measurement uncertainty.

关键词： astrometry - Galaxy: kinematics and dynamics - stars: early-type - Galaxy:solar neighborhood

Distributed GEP query optimization on grid service

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The Journal of China Universities of Posts and Telecommunications 2010年第3期17卷 118-122,128页

作者： DENG Yong, WANG Ru-chuan College of Computer, nanjing university of Posts and Telecommunications, nanjing 210003, China College of Computer Nanjing University of Posts and Telecommunications Nanjing 210003 China

In order to better solve the problem of distributed query optimization, a query optimization algorithm on gene expression programming （GEP）（QO-GEP） is presented. On the basis of QO-GEP, distributed GEP query optimization on grid service （DGEPQO-GS） is proposed which combines grid service. Simulated experiments show that with the increment of the number of query relation, query time which QO-GEP carries out query decreases apparently. Meanwhile, with the increase of the number of grid nodes, the average querying success rate of DGEPQO-GS increases significantly.

关键词： gene expression programming distributed query grid service query relation

HUBER'S M-ESTIMATOR ON UNDERDETERMINED PROBLEMS

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Journal of Computational Mathematics 1995年第2期13卷 130-143页

作者： Wang Jia-song Tang Sheng-rong (Department of Mathematics, nanjing university, nanjing, China) 南京大学数学系江苏南京

After surveying the theoretical aspects of Huber's M-estimator on underdeter-mined problems, two finite algorithms are presented. Both proceed in a construc-tive manner by moving from one partition to an adjacent one. One of the algorithm,which uses the tuning constant as a continuation parameter, also has the facility to simultaneously estimate the tuning constant and scaling factor. Stable and efficient implementation of the algorithms is presented together with numerical results. The L1-norm problem is mentioned as a special case.

关键词： Za Pro HUBER’S M-ESTIMATOR ON UNDERDETERMINED PROBLEMS

ABSOLUTELY E-PURE MODULES AND E-PURE SPLIT MODULES

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Acta Mathematica Scientia 2011年第1期31卷 207-220页

作者：阎舫宇 Department of Mathematics Nanjing University Department of Basic Courses China Pharmaceutical University

We first introduce the concepts of absolutely E-pure modules and E-pure split modules. Then, we characterize the IF rings in terms of absolutely E-pure modules. The E-pure split modules are also characterized.

关键词： Absolutely E-pure module E-pure split module IF ring copure flat module