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STUDY ON URBAN LAND SAVING IN THE ECONOMICDEVELOPED COASTAL REGION OF china

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Chinese Geographical science 2001年第1期11卷 11-16页

作者： SHEN Jian-rong, CHEN Shuang, YAO Shi-mou (department of Urban and Resources science, nanjing university,{3., P. R. china nanjing Institute of Geography and Limnology, the Chinese Academy of sciences, nanjing 210008, P. K china) department of Urban and Resources science Nanjing University Nanjing P. R. China nanjing Institute of Geography and Limnology the Chinese Academy of Sciences Nanjing P. R. China

In the initial period of industrialization a great deal of land is needed for Chinese industry development as well as land resource per person of china is much lower than the average value in the world, thus it is necessary to save land in Chinese urban constrUction. This paper mainly discussed the features of urban land use in economic developed coastal cities: one is that the index of urban land per person in middle-small cities was higher than in large cities; another is that urban land has not been used highly and strongly; the third is that the industrial land occupied an irrationally large percentage of whole urban land; the final is that rural enterprises took up a quantity of land. Thereafter, this paper put forward five land-saving measures: first, to adopt the idea of saving land; next, to adjust the land-use structure when redeveloping the old city and alternate some land use when adjusting the industry structure of the city; the third, to develop the system of payment for using land and the management of urban planning; finally to enhance the effective regional plan and the urban landuse plan.

关键词： cities land saving measures the coastal region of china

PRIMAL PERTURBATION SIMPLEX ALGORITHMS FOR LINEAR PROGRAMMING

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Journal of Computational Mathematics 2000年第6期18卷 587-596页

作者： Ping-qi Pan (department of Applied Mathematics, Southeast university, nanjing 210096,{3..) 东南大学江苏南京 210096

In this paper, we propose two new perturbation simplex variants. Solving linear programming problems without introducing artificial variables, each of the two uses the dual pivot rule to achieve primal feasibility, and then the primal pivot rule to achieve optimality. The second algorithm, a modification of the first, is designed to handle highly degenerate problems more efficiently. Some interesting results concerning merit of the perturbation are established. Numerical results from preliminary tests are also reported. [ABSTRACT FROM AUTHOR]

关键词： linear programming perturbation primal simplex algorithm partially revised tableau

Predicting octanol/water partition coefficient using solvation free energy and solvent-accessible surface area

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Journal of Environmental sciences 2001年第3期13卷 299-303页

作者： LIU Xin hui, WU Chun de, HAN Shuo kui, WANG Lian sheng(State Key Laboratory of Pollution Control and Resource Reuse, department of Environmental science, School of the Environment, nanjing university,{3., china. State Key Laboratory of Pollution Control and Resource Reuse Department of Environmental Science School of the Environment Nanjing University Nanjing 210093 China.

The regression model for octanol/water partition coefficients ( K ow ), is founded with only two molecular descriptors available through quantum chemical calculations: solvation free energy (Δ G S ), and solvent accessible surface area (SASA). For the properties of 47 organic compounds from 17 types, the model gives a correction coefficient (adjusted for degrees of freedom) of 0 959 and a standard error of 0 277 log unit. It is a suitable way to predict the partition properties that are related to solute solvent interactions in the water phase.

关键词： solvation free energy solvent accessible surface area quantum chemical descriptor

THE ADVANCES ON 3. TECHNOLOGICAL APPLICATIONS IN GRASSLAND AND AGRICULTURAL ECOSYSTEM OF china

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南京大学学报(自然科学) 1999年第5期 613-615页

作者： Li Jianlong (department of Biological science & Technology, nanjing university,{3.,nanjing,PRC )

Ｔｈｅｇｒａｓｓｌａｎｄｙｉｅｌｄｗａｓａｎｉｍｐｏｒｔａｎｔｉｎｄｅｘｔｏｅｓｔｉｍａｔｅｔｈｅｐｒａｔａｃｕｌｔｕｒａｌｐｒｏｄｕｃｔｉｖｉｔｙ，ａｎｄｉｔｗａｓａｌｓｏｔｈｅｂａｓｉｓｔｏｐｌａｎｔｈｅｐｒｏｄ... 详细信息

Ｔｈｅｇｒａｓｓｌａｎｄｙｉｅｌｄｗａｓａｎｉｍｐｏｒｔａｎｔｉｎｄｅｘｔｏｅｓｔｉｍａｔｅｔｈｅｐｒａｔａｃｕｌｔｕｒａｌｐｒｏｄｕｃｔｉｖｉｔｙ，ａｎｄｉｔｗａｓａｌｓｏｔｈｅｂａｓｉｓｔｏｐｌａｎｔｈｅｐｒｏｄｕｃｔｉｏｎｓｏｆａｎｉｍａｌｈｕｓｂａｎｄｒｙ．Ｉｔｈａｄａｎｉｍｐｏｒｔａｎｔｍｅａｎｉｎｇｗｈｅｔｈｅｒｔｈｅｄｙｎａｍｉｃｇｒａｓｓｌａｎｄｉｎｆｏｒｍａｔｉｏｎｉｎｌａｒｇｅａｒｅａｓｃｏｕｌｄｂｅｔｉｍｅｌｙｇｒａｓｐｅｄｉｎｏｒｄｅｒｔｏｃａｌｃｕｌａｔｅｇｒａｓｓｌａｎｄｇｒａｚｉｎｇｃａｐａｃｉｔｙ，ｔｏａｒｒａｎｇｅｔｈｅｐｒｏｄｕｃｔｉｏｎｏｆｇｒａｓｓｌａｎｄａｎｄｌｉｖｅｓｔｏｃｋａｎｄｔｏｉｍｐｒｏｖｅｔｈｅｐｒｏｄｕｃｔｉｖｉｔｙｏｆａｎｉｍａｌｈｕｓｂａｎｄｒｙ．Ｈｏｗｅｖｅｒ，ｔｈｅｔｒａｄｉｔｉｏｎａｌｍｅｔｈｏｄｗａｓｌｉｍｉｔｅｄｂｙｔｈｅｓｍａｌｌａｒｅａｓｃｏｎｔｒｏｌｌｅｄｂｙａｆｅｗｓａｍｐｌｅｓ，ｌｏｎｇｍｅａｓｕｒｉｎｇｐｅｒｉｏｄｉｃｉｔｙ，ｔｉｍｅｃｏｎｓｕｍｉｎｇａｎｄｈｉｇｈｐｒｉｃｅ．Ｉｔｃｏｕｌｄｎｏｔｔｉｍｅｌｙｐｒｏｖｉｄｅｔ...

关键词： Dynamic Grassland amd Agricultural Monitoring Large Area Grassland Yield Estimation PPR Technology Agricultural Remote Sensing Technology GIS

Phase space transport in a map of asteroid motion

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Communications in Nonlinear science and Numerical Simulation 2000年第1期5卷 1-5页

作者： Liyong ZHOU Yisui SUN and Jilin ZHOU department of Astronomy, nanjing university, nanjing 210093,{3. e-mail: buffalol @public1 .ptt.js. cn department of Astronomy Nanjing University Nanjing 210093 China

We have studied the chaotic transport in a nonlinear model directly applicable to asteroid motion. An exponential and an algebraic diffusion law are observed in different regions of the phase space. We have also investigated the effects of small perturbations and found they can not only accelerate but also decelerate the transport.

关键词： phase space transport symplectic map asteroid

STUDY ON THE SILVER-RIM STRUCTURE OF PRIMARY GOLD GRAINS

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南京大学学报(自然科学) 1998年第1期 128-130页

作者：  Hu Huan Wang Rucheng Lu Jianjun(department of earth sciences,{3., nanjing, 210093)

ＳＴＵＤＹＯＮＴＨＥＳＩＬＶＥＲ┐ＲＩＭＳＴＲＵＣＴＵＲＥＯＦＰＲＩＭＡＲＹＧＯＬＤＧＲＡＩＮＳＨｕＨｕａｎＷａｎｇＲｕｃｈｅｎｇＬｕＪｉａｎｊｕｎ（ＤｅｐａｒｔｍｅｎｔｏｆＥａｒｔｈＳｃｉｅｎｃｅｓ，Ｎａｎｊｉｎ... 详细信息

ＳＴＵＤＹＯＮＴＨＥＳＩＬＶＥＲ┐ＲＩＭＳＴＲＵＣＴＵＲＥＯＦＰＲＩＭＡＲＹＧＯＬＤＧＲＡＩＮＳＨｕＨｕａｎＷａｎｇＲｕｃｈｅｎｇＬｕＪｉａｎｊｕｎ（ＤｅｐａｒｔｍｅｎｔｏｆＥａｒｔｈＳｃｉｅｎｃｅｓ，ＮａｎｊｉｎｇＵｎｉｖｅｒｓｉｔｙ，Ｎａｎｊｉ...

关键词： native gold silverrim structure dynamic constraint

The Comparable Structure of Exchange Rings

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Acta Mathematica Sinica,English Series 2002年第1期18卷 89-94页

作者： CHEN Huan Yin QIN Hou Rong department of Mathematics. Hunan Normal university. Changsha 410006. P. R. china department of Mathematics. nanjing university. nanjing 210093. P. R. china department of Mathematics Hunan Normal University Changsha P. R. China department of Mathematics Nanjing University Nanjing P. R. China

We obtaim a new substitution for modules over exchange rings satisfving related compara- bilitv. Also we investigate the structure of modules over exchange rings satisfying power comparability and provide a new class ... 详细信息

关键词： Related comparability Power comparability Exchange ring

A non-commutative time-frequency tomography

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Chinese science Bulletin 2007年第17期52卷 2438-2442页

作者： LIU JianCai, XU JiaKai, NING XinBao & TIAN Run Key Laboratory of Modern Acoustics, department of Electronics science and Engineering Institute of Biological Medical Electronic Engineering, nanjing university,{3., china Key Laboratory of Modern Acoustics Department of Electronics Science and Engineering Institute of Biological Medical Electronic Engineering Nanjing University Nanjing 210093 China

The characterization of non-stationary signal requires joint time and frequency information. However, time and frequency are a pair of non-commuting variables that cannot constitute a joint probability density in the time-frequency plane. The time-frequency distributions have difficult interpretation problems arising from negative and complex values or spurious components. In this paper, we get time-frequency information from the marginal distributions in rotated directions in the time-frequency plane. The rigorous probability interpretation of the marginal distributions is without any ambiguities. This time-frequency transformation is similar to the computerized axial tomography (CT or CAT) and is applied to signal analysis and signal detection and reveals a lot of advantages especially in the signal detection of the low signal/noise (S/N).

关键词：非交换时频X线断层摄影术边缘分布医学影像学时频分布

TENSILE　PROPERTIES　AND　CREEP　RESISTANCE　OF　Fe_3.l－BASED　ALLOYS　CONTAINING　NIOBIUM

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Acta Metallurgica Sinica(English Letters) 1996年第2期9卷 135-139页

作者： ZHANG Zhonghua SUN Yangshan GUO Jun(department of Materials science and Engineering, Southeast university, {3. 210096,china) Southeast Univ Nanjing China

Small amount(0.5-0.8at.%) of niobium addition to the multicomponent alloys based on Fe3.l(Fe-28Al-5Cr-0.5Mo-0.05Zr-0.05B-0.1Ce) results in the microstructural refinement and the increase in the yield strength at temperatures up to 600℃,but is not beneficial to room temperature *** of microanalysis indicate that the addition of niobium causes the formation of precipitates with complex compositions which strengthen both matrix and grain boundaries and enhance the creep resistance of the alloys.

关键词： Fe_3.l,Nb,tensile property creep