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Estimation of annual actual evapotranspiration from nonsaturated land surfaces with conventional meteorological data

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Science china Earth sciences 2004年第3期47卷 239-246页

作者： QIU Xinfa1, ZENG Yan2. MIAO Qilong1 & YU Qiang2.1. department of Geography, nanjing Institute of Meteorology, nanjing 2.0044, china 2. Institute of Geographic sciences and Natural resources Research, Chinese Academy of sciences, Beijing 100101, china department of Geography Nanjing Institute of Meteorology Nanjing 210044 China Inst. of Geogr. Sci./Nat. Rsrc. Res. Chinese Academy of Sciences Beijing 100101 China

Views diverge greatly on the relationship between actual evapotranspiration (AE) and potential evapotranspiration (PE). Penman showed that AE is determined in intensity by PE and changes proportionally as a function of PE. In contrast, Bouchet indicated that AE deter-mines PE and varies inversely with PE. Based on nearly 30 years data from 432.weather stations and 512.hydrological stations in china, the two different theories, Penman抯 assumption and Bouchet抯 complementary relationship between AE and PE, were tested on nine river basins. With data integration technique, the complementary relationship between AE and PE was dis-played entirely. A general model to estimate the actual evapotranspiration from nonsaturated surfaces by routine meteorological observations has been established on the basis of thorough analysis of the concept of PE. The results show that the calculations are all in error control of <10%, except for a few years over the Yellow River Basin.

关键词： complementary relationship of evapotranspiration, potential evapotranspiration, actual evapotranspiration.

Regular n-simplices in R^n with vertices in Z^(n)

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Science china Mathematics 2004年第1期47卷 104-113页

作者： XIA Jianguo & QIN Hourongdepartment of Mathematics, nanjing Normal {2., nanjing 2.0097, china (email: jgxia@***) department of Mathematics, nanjing university, nanjing 2.0093. china Dept. of Math. Nanjing Normal Univ. Nanjing 210097 China Dept. of Math. Nanjing Univ. Nanjing 210093 China

In this paper the Ⅰ and Ⅱ regular n-simplices are introduced. We prove that the sufficient and necessary conditions for existence of an Ⅰ regular n-simplex in Rn are that if n is even then n = 4m(m + 1), and if n is odd then n = 4m + 1 with that n + 1 can be expressed as a sum of two integral squares or n = 4m - 1, and that the sufficient and necessary condition for existence of a Ⅱ regular n-simplex in Rn is n = 2.2.- 1 or n = 4m(m+1)(m 6 N). The connection between regulars-simplex in Rn and combinational design is given.

关键词： regular n-simplex in Rn, quadratic form.

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 {2.,nanjing 2.002.,china ~2.0} of Biotechnology,nanjing Medical {2.,nanjing 2.002.,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 12. 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

A predict-correct projection method for monotone variant variational inequalities

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Chinese Science Bulletin 1998年第15期43卷 1264-1267页

作者： HAN Qiaoming 1 and HE Bingsheng 2.1. Institute of Applied Mathematics, Chinese Academy of sciences, Beijing 100080, china 2. {2. of Mathematics, nanjing university, nanjing 2.0093. china Institute of Applied Mathematics Chinese Academy of Sciences Beijing China department of Mathematics Nanjing University Nanjing China

A predict_correct projection method is presented for solving monotone variant variational inequalities, which could exploit the advantages and overcome the difficulties of both explicit and implicit projection methods.

关键词： variant variational inequality explicit projection method implicit projection method predict_correct projection method.

Numerical study of rapid cyclogenesis over sea

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Acta Oceanologica Sinica 1989年第1期8卷 51-62页

作者： Du Jun and Yu Zhihao department of Atmospheric sciences,{2., nanjing, china Dept. of Atmospheric sciences Nanjing Univ Nanjing China. China

A five-layer primitive equation model was used in the study of rapid cyclogenesis over sea. The numerical simulations show that'the Tibetan Plateau, large-scale baroclinicity and heat flux from the sea surface are the three important agents to produce cyclonic vorticity along the east coast of china. The diagnostic computation of a 2. h control simulation indicates that the nonlinear vorticity advec-tion, baroclinicity and diabatic heating are also responsible for the development of the extratropical cyclones over seas.

关键词： Numerical study of rapid cyclogenesis over sea over

EIT waves and coronal magnetic field diagnostics

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Science china(Physics,Mechanics & Astronomy) 2009年第11期52卷 1785-1789页

作者： CHEN PengFei department of Astronomy, nanjing university,{2. department of Astronomy Nanjing University Nanjing China

Magnetic field in the solar lower atmosphere can be measured by the use of the Zeeman and Hanle effects. By contrast, the coronal magnetic field well above the solar surface, which directly controls various eruptive phenomena, can not be precisely measured with the traditional techniques. Several attempts are being made to probe the coronal magnetic field, such as force-free extrapolation based on the photospheric magnetograms, gyroresonance radio emissions, and coronal seismology based on MHD waves in the corona. Compared to the waves trapped in the localized coronal loops, EIT waves are the only global-scale wave phenomenon, and thus are the ideal tool for the coronal global seismology. In this paper, we review the observations and modelings of EIT waves, and illustrate how they can be applied to probe the global magnetic field in the corona.

关键词： coronal mass ejections (CMEs) magnetic field diagnostics magnetohydrodynamics (MHD)

LIMIT CYCLES AND BIFURCATION CURVES FOR THE QUADRATIC DIFFERENTIAL SYSTEM (III)_(m=0) HAVING THREE ANTI-SADDLES (I)

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Chinese Annals of Mathematics,Series B 1996年第2期17卷 167-174页

作者： YE YANQIAN department of Mathematics, nanjing university, {2. 2.0008, china. 南京大学数学系江苏南京

For the quadratic system: x=-y+δx + lx2.+ ny2. y=x(1+ax-y) under conditions -10 the author draws in the (a, ()) parameter plane the global bifurcationdiagram of trajectories around O(0,0). Notice that when na2.l < 0 ... 详细信息

关键词： Quadrtic systen Anti-saddle Bifurcation curve Limit cycle

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 {2., nanjing university, nanjing 2.0093. china Key Laboratory of Coast & Island Development of Ministry of Education of china, nanjing university, nanjing 2.0093. 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 2.0-800 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.

A COLUMN RECURRENCE ALGORITHM FOR SOLVING LINEAR LEAST SQUARES PROBLEM

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Journal of Computational Mathematics 1996年第4期14卷 301-310页

作者： J.X. Zhao(department of Mathematics, nanjing university, {2. china) 南京大学数学系江苏南京

A new column recurrence algorithm based on the classical Greville method and modified Huang update is proposed for computing generalized inverse matrix and least squares solution. The numerical results have shown the ... 详细信息

关键词： Math A COLUMN RECURRENCE ALGORITHM FOR SOLVING LINEAR LEAST SQUARES PROBLEM ABS