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Analysis and Modeling on the Spatial Structure of Urban Land Use: A case of Jinan, china

Chinese Journal of Population,Resources and Environment 2007年第2期5卷 34-40页

作者： Zhao Huixia1, 3, Zhang Zulu2. Jiang Luguang 1 1. Institute of Geographical Sciences and Natural Resources Research, Chinese Academy of Sciences, beijing 100101, china 2. College of Population, Resources and Environment, Shandong Normal University, Jinan Shandong 2.0014, china 3. graduate school of the Chinese Academy of Sciences, beijing 100039, china Institute of Geographical Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China graduate school of the Chinese Academy of Sciences Beijing 100039 China College of Population Resources and Environment Shandong Normal University Jinan Shandong 250014 China

Based on the data of urban land use obtained by remote sensing interpretation from aero images in 1986 and 2.04, the spatial structure of Jinan is studied in this paper with the method of Geographic Information System (GIS). According to the proportion of land for residence, industry and commerce, the urban district can be distinguished into three rings. Compared with the traditional theory of the ring structure in Western coun- tries, they have many distinctive characteristics. The main func- tions of the inner ring include residence, business and banking, but the proportion of residential land (more than 50%) is considerably higher than that of the cities in Western countries. The land proportion for residence and industry in the intermediate ring is equal on the whole. The main land of the outside ring is for industrial use. From 1986 to 2.04, great changes have taken place on the land proportion of different types of use. In the inner ring, the land for residential and industrial use has shrunk much while the land for commercial use has increased. In the intermediate ring, the changes of the three types of land use were not very much and the temporal variation was relatively stable. On the contrary, the structure in the outside ring varies acutely. Though most of it is also for industrial use, the proportion of residential land has in- creased much. The three rings can also be divided into several sectors respectively, according to the function of land use clusters. New trends and mechanisms of the changes of land use impacting the urban structure were proposed in the end of the paper.

关键词： urban land use ring structure sector structure Jinan

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Geometry of Broad Line Regions of Active Galactic Nuclei

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Chinese Journal of Astronomy and Astrophysics 2008年第1期8卷 50-62页

作者： Xiao-Rong Lü1 Key Laboratory for Particle Astrophysics, Institute of High Energy Physics, Chinese Academy of Sciences, beijing 100049 2.graduate {2. of Chinese Academy of Sciences, beijing 100049 Key Laboratory for Particle Astrophysics Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 graduate school of Chinese Academy of Sciences Beijing 100049

It has long remained an open question as to the geometry of the broad line region （BLR） in active galactic nuclei （AGNs）. The reverberation mapping technique which measures the response of the broad emission lines to the ionizing continuum, when combined with multiwavelength continuum fitted by sophisticated accretion disks, provides a way of probing the BLR geometry. We analyze a sample of 35 AGNs, which have been monitored by the reverberation mapping campaign. In view of energy budget, the reverberation-based BH masses are found to be in agreement with those obtained by accretion disk models in two thirds of the present sample while the reverberation mapping methods underestimate the BH masses in about one third of objects, as also suggested by CoUin et al. in a recent work. We point out that there are obviously two kinds of BLR geometry, which are strongly dependent on the Eddington ratio, and separated by the value LBol/LEdd - 0.1. These results prefer a scenario of the disk and wind configuration of the BLR and identify the Eddington ratio as the physical driver regulating the wind in the BLR.

关键词： accretion, accretion disks - galaxies active - galaxies Seyfert - quasars general

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A NOTE ON THE S-UNIT EQUATION OVER FUNCTION FIELD

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Systems Science and Mathematical Sciences 1999年第S1期12卷 14-16页

作者： FENG Keqin(graduate school at {2., University of Science and Technology of china,P.O.Box 3908,{2. 100039, china)

In this note we show that the Mason’s upper bound of deg(u) for S-units u andv satisfying u + v = 1 over function field K = k(C) can be attained for any algebraicallyclosed coefficient field k and for some hyperellip... 详细信息

关键词： S-unit equation function fields.

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Classification and Enumeration of Matched Free Response Matrices of Linear Finite Automata

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Acta Mathematica Sinica,English Series 1997年第1期13卷 133-144页

作者： Dai Zongduo Ye Dingfeng Zhai Qibin Ou Haiwen (graduate school of Academia Sinica,{2. 100039,china) graduate school of Academia Sinica 100039 Beijing China

If H and G are the transfer function matrix and the free response matrix of a linear finite automaton,then G is called a free response matrix matched to *** H,let(H)be the set of all possible free response matrices ma... 详细信息

关键词： Finite automation Free response matrix Classification Enumeration

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The　Analysis　and　Numerical　Simulation　of　Dynamical　Functions　of　the　Transpiration　Cooling　Control　System　with　Surface　Ablation

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Journal of Systems Engineering and Electronics 1994年第1期5卷 44-52页

作者： Xu Yanhou Wu Guangyu(Department of Modern Mechanics,University of Science & Technology of china, Hefei, 2.002.)Gong Guanghui(graduate {2. of USTC, beijing, 100039)Yang Xueshi(P.O.Box 142.2.6, beijing, 100854) Department of Modern Mechanics University of Science & Technology of China Hefei 230026 graduate school of USTC Beijing 100039 P.O. Box 142.2.6 Beijing 100854

This problem is a nonlinear control system with variable-domain distributed parameter. In this paper, the numerical simulation of the dynamic functions has been carried out by transforming this problem to a fixed-domain initial-boundary value problem, and the numerical results are obtained: (1) Thedistribution of temperature rises, the ablation amount and velocity of the thermal shield vary with the time; (2. The maximum ablating velocity, the time of the ablation beginning and ending related to thetranspiration quantity. This method succeeds in overcoming the difficulty brought up by variable *** the other hand, the critical transpiration quantity for the surface to start ablating, the maximum ablating velocity and time of the ablation ending are obtained theoretically.

关键词： Ablation,Transpiration cooling Variable domain Distributed parameter control NumericalSimulation

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Comparative study of pollination biology of two closely related alpine Primula species,namely Primula beesiana and *** (Primulaceae)

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Journal of Systematics and Evolution 2010年第2期48卷 109-117页

作者： 1,2.hi-Kun WU 1Chang-Qin ZHANG 1(Kunming Institute of Botany,Chinese Academy of Sciences,Kunming 6502.4,china) 2.graduate {2. of Chinese Academy of Sciences,beijing 100049,china) (Kunming Institute of Botany Chinese Academy of Sciences Kunming 650204 China) (graduate school of Chinese Academy of Sciences Beijing 100049 China)

The comparative pollination biology of a population of Primula beesiana,a population of ***,and an overlapping population of these two species in Yulong Shan,Yunnan Province,china,was studied in 2.04 and *** results indicate that both *** and *** are typical heterostylous and obligate outcrossing species;the main pollinators of the two species were bees and *** the sites of all three populations,the main pollinating visitors of the two species showed preference for one of the two species,resulting in the ethological isolation of the two species by the *** ethological isolation contributes to the reproductive isolation of the two species,which supports the hypothesis that *** and *** are two distinct *** reproductive isolation of the two species (ethological isolation) is probably an important mechanism in maintaining species boundaries in the genus and has contributed to the species diversification of Primula in the *** addition,gene exchanges between *** and *** has occurred to some extent in the overlapping population,but whether natural hybridization has contributed to species diversification in Primula remains to be determined.

关键词： pollination biology Primula beesiana Primula bulleyana reproductive isolation

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The Global Existence of One Type of Nonlinear Kirchhoff String Equation

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Acta Mathematicae Applicatae Sinica 2003年第3期19卷 477-484页

作者： Xiao-yi Zhangbeijing graduate {2. of china Academy of Engineering Physics, beijing 100088, china beijing graduate {2. of china Academy of Engineering Physics Beijing China

In this paper, the global well-posedness of initial-boundary value problem to the nonlinear Kirchhoff equation with source and damping term is established by energy method.

关键词： Kirchhoff equation global well-posedness

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Quasi-secure quantum dialogue using single photons

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Science china(Physics,Mechanics & Astronomy) 2007年第5期50卷 558-562页

作者： YANG YuGuang1,2.& WEN QiaoYan31 College of Computer Science and Technology, beijing University of Technology, beijing 10002.,{2. 2.State Key Laboratory of Information Security, graduate University of the Chinese Academy of Sciences, beijing 100049,{2. 3 school of Science, beijing University of Posts and Telecommunications, beijing 100876,{2. College of Computer Science and Technology Beijing University of Technology Beijing China State Key Laboratory of Information Security Graduate University of the Chinese Academy of Sciences Beijing China school of Science Beijing University of Posts and Telecommunications Beijing China

A quasi-secure quantum dialogue protocol using single photons was proposed. Different from the previous entanglement-based protocols, the present protocol uses batches of single photons which run back and forth between the two parties. A round run for each photon makes the two parties each obtain a classical bit of information. So the efficiency of information transmission can be increased. The present scheme is practical and well within the present-day technology.

关键词： quantum dialogue, single photon, quantum secure direct communication

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Comment on “Evolution model of the earth's limited expanding” from comparative planetology

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Chinese Science Bulletin 2001年第17期46卷 1495-1496页

作者： SHI Yaolingraduate school, University of Science and Technology of{2., Chinese Academy of Sciences, beijing 100039,{2. graduate school University of Science and Technology of China Chinese Academy of Sciences Beijing China

In the article 'Evolution Model of the Earth’s Limited Expanding' published in Volume 45 Number (4) of Chinese Science Bulletin[1], the author suggests that the earth expands according to a law R(t) = R0+A(1 -exp(β(t-ts))) (remark: this formula was mistakenly printed as R(t) = R0 + Aexp(β(t-ts)) in the and formula (12. of the text of ref. [1]). According to ref. [1], the earth was formed 4.6 billion years ago. After 0.3 billion years from its birth (ts), it started expansion from an initial radius R0 of 4651 km, and may reach a final maximum radius of R0+A = 6511 km. In the 4.6 billion years history, the radius of the earch has increased by 172. km, or the density decreased from 142.0 km/m3 (2.57 times the present density) to 552. kg/m3 within the latest 4.3 billion years.

关键词： from comparative planetology Evolution model of the earth’s limited expanding

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Pollution characteristics of atmospheric fine particles and their secondary components in the atmosphere of Shenzhen in summer and in winter

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Science china Chemistry 2006年第5期49卷 466-474页

作者： NIU Yuwen1,2.HE Lingyan1,2.HU Min2.ZHANG Jing2.& ZHAO Yunliang2.1. Shenzhen graduate school of Peking University,Shenzhen 518055,{2. 2. State Joint Key Laboratory of Environmental Simulation and Pollution Control,College of Environmental Sciences,Peking University,beijing 100871,{2. Shenzhen graduate school of Peking University Shenzhen China State Joint Key Laboratory of Environmental Simulation and Pollution Control College of Environmental Sciences Peking University Beijing China

Two field measurements for atmospheric fine particles were conducted in Baoan district of Shenzhen during the summer and winter in 2.04. Totally 30 sets of 2. h samples were collected, and then the mass concentrations and chemical compositions were determined. The seasonal varia- tions and secondary pollution characteristics of fine particles during the sampling periods were dis-cussed with meteorological factors. The results show that seasonal variations of atmospheric particles are significant in Shenzhen. The average mass concentrations of PM2.5 and PM10 in summer were 35 μg·m-3 and 57 μg·m-3, respectively, and those in winter were 99 μg·m-3 and 135 μg·m-3, respec-tively. The concentrations of both PM2.5 and PM10 in winter increased 184% and 137%, respectively, compared to those in summer. PM2.5 accounted for 61% and 75% of PM10 in summer and in winter, respectively, indicating severe fine particle pollution in Shenzhen. During the summer and winter sampling periods, the mean OC/EC ratios were 3.4 and 1.6, respectively. The estimated secondary organic carbon (SOC) averagely accounted for 56% and 6% of the total OC in summer and in winter, respectively, which implies a major contribution of SOC to OC in summer. During the continuous high temperature period in summer, both the concentrations and fractions of secondary aerosol compo-nents in PM2.5 were highly elevated, suggesting severe secondary pollution again. The prevailing wind was from South china Sea in summer, and the air quality was good. The prevailing wind in winter was from china's Mainland to the north, and the polluted air mass led to poor air quality.

关键词： PM2.5, mass concentration, secondary pollution, seasonal variation, Shenzhen.

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