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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

A CONSTRUCTIVE PROOF OF THE INVERSION FORMULA FOR ZONAL FUNCTIONS ON SL(2, R)

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Chinese Annals of Mathematics,Series B 1996年第1期17卷 81-88页

作者： XIAO CHANGBAI ZHENG WEIXING SU WEIYI (Department of Mathematics, nanjing university nanjing 210093, China.) Department of Mathematics Nanjing University Nanjing 210093 China

A constructive proof is given for the inversion formula for zonal functions on SL(2, R). A concretely constructed sequence of zonal drictions are proved to satisfy the inversion formula obtained by Harish-Chandra for compact supported infinitely differentiable zonal *** use of the property of this sequence somehow similar to that of approxination kernels,the authors deduce that the inversion formula is true for continuous zonal functions on SL(2, R)under some condition. The classical result can be viewed as a corollary of the results here.

关键词：线性函数倒置公式近似值数学分析证明方法

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

Landscape structure and land uese on county level in northeastern Yunnan Province of China——a case study of Huize County

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Journal of Environmental Sciences 2000年第3期12卷 355-360页

作者： WANG Jin\|liang, NI Shao\|xiang (College of Geographical Science, nanjing Normal university, nanjing 210097, China) 南京师范大学江苏南京 2 1 0 0 97

Taking Huize County as an example, the paper analyzed the landscape structure(landscape element structure, landscape type structure, landscape spatial structure, landscape succession structure) and the relations between landscape structure and land use. It was pointed out that the agriculture should be developed in harmony with the landscape structure in the study area.

关键词： landscape structure land use agriculture Yunnan Province China

On the Conditions of a Center and General Integrals of Quadratic Differential Systems

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Acta Mathematica Sinica,English Series 2001年第2期17卷 229-236页

作者： Wei Yin YE Department of Mathematics. nanjing Normal university. nanjing 210097, P. R. China Yan Qian YE Department of Mathematics. nanjing university, nanjing 210093, P. R. China Department of Mathematics Nanjing Normal University Nanjing 210097 P. R. China Department of Mathematics Nanjing University Nanjing 210093 P. R. China

We give the general integral of quadratic differential system with center in two cases under the Chinese classification.

关键词： Quadratic differential system Center General integral

Surface Billiards and Nonvanishing Lyapunov Exponents

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Acta Mathematica Sinica,English Series 1997年第1期13卷 21-34页

作者： Cheng Jian (Department of Mathematics,nanjing university,nanjing 210008,China) 南京大学数学系江苏南京

We study in this paper the billiards on surfaces with mix-valued Gaussian curvature and the condition which gives nonvanishing Lyapunov exponents of the *** introduce a criterion upon which a small perturbation of the... 详细信息

关键词： Billiards Lyapunov exponents Curvature

Mitochondrial rRNA and tRNA and hearing function

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Cell Research 2007年第3期17卷 227-239页

作者： Guangqian Xing~1 Zhibin Chen~1 Xin Cao~2 ~1Department of Otolaryngology,the First Affiliated Hospital of nanjing Medical university,nanjing 210029,China ~2Department of Biotechnology,nanjing Medical university,nanjing 210029,China Department of Otolaryngology the First Affiliated Hospital of Nanjing Medical University Nanjing China Department of Biotechnology Nanjing Medical University Nanjing China

The human ear is a delicate sensory apparatus of hearing for normal communication,and its proper functioning is highlydependent on mitochondrial oxidative *** first mitochondrial point mutation for nonsyndromic andaminoglycoside-induced hearing loss was identified in *** then a number of inherited mitochondrial mutationshave been implicated in hearing *** of the molecular defects responsible for mitochondrial disorder-associatedhearing loss are mutations in the 12S rRNA gene and tRNA *** this review,after a short description of normal hear-ing mechanisms and mitochondrial genetics,we outline the recent advances that have been made in the identification ofdeafness-associated mitochondrial mutations,and discuss how mitochondrial dysfunction contributes to hearing loss.

关键词： mitochondrial DNA rRNA tRNA gene mutation aminoglycosides hearing loss

An SANS Study of Decomposition Kinetics in Amorphous Cu_(12.5)Ni_(10)Zr_(41)Ti_(14)Be_(22.5)

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Journal of Materials Science & Technology 1998年第3期14卷 193-199页

作者： Junming LIU(National Laboratory of Solid State Microstructures, nanjing university and Center for Advanced Studies in Scienceand Technology of Microstructures, nanjing 210093, China) National Laboratory of Solid State Microstructures Nanjing University Center for Advanced Studies in Science and Technology of Microstructures Nanjing 210093 China

Phase decomposition in amorphous Cu12.5Ni10Zr411Ti14Be22.5 alloy as annealed in the super-cooled liquid range was studied by applying small angle neutron scattering (SANS). As annealed between 600 K and 700 K, the alloy was observed to decompose into two new amorphous phases,with the second phase precipitates embedded in the matrix of the first. Long time annealing of the alloy results in crystallization in addition to evolution of the decomposed *** kinetic diagram of the decomposition and crystallization for this alloy is given. The second phase precipitates have several nanometers in size and occupy a quite low volume fraction. The decomposition of the supercooled liquid in overall temperature range exhibits the features of spinodal reaction.

关键词： Be Zr SANS Ni Ti

Characterizations of α-Bloch functions on the unit ball without use of derivative

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Science China Mathematics 2008年第11期51卷 1965-1981页

作者： CHEN HuaiHui School of Mathematics and Computer Science, nanjing Normal university, nanjing 210097, China School of Mathematics and Computer Science Nanjing Normal University Nanjing China

In this paper we establish characterizations of α-Bloch functions on the unit ball without use of derivative, which are stronger, more precise and general than those obtained by Nowak and Zhao.

关键词： α-Bloch function unit ball Bergman metric