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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 250014, 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 2004, 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 2004, 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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Measurement Methodology for Monitoring Fouling Resistance in Condenser of Chiller

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湖南大学学报（自然科学版） 2009年第S1期36卷 119-122页

作者： YU Dan1,3,GAN Li-si1,CAO Yong2(1.beijing university of Technology,beijing 100022,china 2.Build environment and Energy Efficiency,china Academy of Building Research,beijing 100013,china 3.beijing Institute of Civil Engineering and Architecture,beijing 100044,china) beijing university of Technology Beijing 100022 China beijing Institute of Civil Engineering and Architecture Beijing 100044 China Build environment and Energy Efficiency China Academy of Building Research Beijing 100013 China

This paper established an on-line monitoring model for fouling resistance of cooling water based on heat transfer theory,which was mainly applied to the fouling resistance test for condenser of chiller in operation,and the test requirements were *** proves that the load ratio of chiller has big influence on the test result,and the best load ratio for test is the range of 80%～100%.A case has been executed to validate the model's feasibility.

关键词： fouling resistance monitoring condenser cooling water

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Debris Flow Hazard Assessment Based on Support Vector Machine

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Wuhan university Journal of natural Sciences 2006年第4期11卷 897-900页

作者： YUAN Lifeng 1, 2 , ZHANG Youshui 3 1. Institute of Mountain Hazards and environment, Chinese Academy of Sciences, Chengdu 610041, Sichuan, china 2. Graduate university of Chinese Academy of Sciences, beijing 100049, china 3. Institute of Geographical Sciences and natural resources Research, Chinese Academy of Sciences, beijing 100101, china Institute of Mountain Hazards environment Chinese Academy of Sciences 610041 Chengdu Sichuan China Graduate university of Chinese Academy of Sciences 100049 Beijing China Institute of Geographical Sciences natural resources Research Chinese Academy of Sciences 100101 Beijing China

Seven factors, including the maximum volume of once flow , occurrence frequency of debris flow , watershed area , main channel length , watershed relative height difference , valley incision density and the length ratio of sediment supplement are chosen as evaluation factors of debris flow hazard degree. Using support vector machine （SVM） theory, we selected 259 basic data of 37 debris flow channels in Yunnan Province as learning samples in this study. We create a debris flow hazard assessment model based on SVM. The model was validated though instance applications and showed encouraging results.

关键词： debris flow hazard assessment support vector machine (SVM)

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Numerical study of the auroral particle transport in the polar upper atmosphere

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Science china(Technological Sciences) 2008年第10期51卷 1759-1771页

作者： CAI HongTao1,2, MA ShuYing1,2 & PU ZuYin3 1 school of Electronic Information, Wuhan university, Wuhan 430079, china 2 Key Laboratory of Geospace environment and Geodesy, Ministry of Education of PRC, Wuhan 430079, china 3 school of Earth and Space Sciences, Peking university, beijing 100871, china 1. school of Electronic Information Wuhan University Wuhan 430079 China 2. Key Laboratory of Geospace environment and Geodesy Ministry of Education of PRC Wuhan 430079 China 3. school of Earth and Space Sciences Peking University Beijing 100871 China

Starting from the Boltzmann equation and with some reasonable assumptions, a one-dimensional transport equation of charged energetic particles is derived by taking account of major interactions with neutral species in the upper atmosphere, including the processes of elastic scattering, the excitation, the ionization and the secondary electron production. The transport equation is numerically solved, for a simplified atmosphere consisting only of nitrogen molecules (N2), to obtain the variations of incident electron fluxes as a function of altitude, energy and pitch angle. The model results can describe fairly the transport characteristics of pre-cipitating auroral electron spectra in the polar upper atmosphere; meanwhile the N2 ionization rates calculated from the modeled differential flux spectra also exhibit good agreements with existing empirical models in terms of several key parameters. Taking the energy flux spectra of precipitating electrons observed by FAST satellite flying over EISCAT site on May 15, 1997 as model inputs, the model-calculated ionization rate profile of neutral atmosphere consists reasonably with that recon-structed from electron density measurements by the radar.

关键词： aurora particle precipitation polar upper atmosphere electron transport equation numerical simulation

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Threshold quantum secure direct communication without entanglement

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Science china(Physics,Mechanics & Astronomy) 2008年第2期51卷 176-183页

作者： YANG YuGuang1,3 & WEN QiaoYan2 1 College of Computer Science and Technology, beijing university of Technology, beijing 100022, china 2 school of Science, beijing university of Posts and Telecommunications, beijing 100876, china 3 State Key Laboratory of Information Security (Graduate school of Chinese Academy of Sciences), beijing 100049, china 1. College of Computer Science and Technology Beijing University of Technology Beijing 100022 China 3. State Key Laboratory of Information Security (Graduate school of Chinese Academy of Sciences) Beijing 100049 China 2. school of Science Beijing University of Posts and Telecommunications Beijing 100876 China

For the first time, a threshold quantum secure direct communication (TQSDC) scheme is presented. Similar to the classical Shamir's secret sharing scheme, the sender makes n shares, S1, …, Sn of secret key K and each receiver keeps a share secretly. If the sender wants to send a secret message M to the receivers, he en-codes the information of K and M on a single photon sequence and sends it to one of the receivers. According to the secret shares, the t receivers sequentially per-form the corresponding unitary operations on the single photon sequence and ob-tain the secret message M. The shared shares may be reusable if it can be judged that there is no eavesdropper in line. We discuss that our protocol is feasible with current technology.

关键词： quantum secure direct communication threshold secure direct communication quantum secret sharing

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Non-Darcy flow in oil accumulation (oil displacing water) and relative permeability and oil saturation characteristics of low-permeability sandstones

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Petroleum Science 2010年第1期7卷 20-30页

作者： Zeng Jianhui Cheng Shiwei Kong Xu Guo Kai Wang Hongyu State Key Laboratory of Petroleum resources and Prospecting China University of Petroleum Beijing 102249 China school of natural resources and Information Technology China University of Petroleum Beijing 102249 China CNPC Greatwall Drilling Company Beijing 100101 China

Hydrocarbon resources in low-permeability sandstones are very abundant and are extensively distributed. Low-permeability reservoirs show several unique characteristics, including lack of a definite trap boundary or caprock, limited buoyancy effect, complex oil-gas-water distribution, without obvious oil-gas-water interfaces, and relatively low oil （gas） saturation. Based on the simulation experiments of oil accumulation in low-permeability sandstone （oil displacing water）, we study the migration and accumulation characteristics of non-Darcy oil flow, and discuss the values and influencing factors of relative permeability which is a key parameter characterizing oil migration and accumulation in low-permeability sandstone. The results indicate that： 1） Oil migration （oil displacing water） in low- permeability sandstone shows non-Darcy percolation characteristics, and there is a threshold pressure gradient during oil migration and accumulation, which has a good negative correlation with permeability and apparent fluidity; 2） With decrease of permeability and apparent fluidity and increase of fluid viscosity, the percolation curve is closer to the pressure gradient axis and the threshold pressure gradient increases. When the apparent fluidity is more than 1.0, the percolation curve shows modified Darcy flow characteristics, while when the apparent fluidity up＂ non-Darcy percolation curve; 3） Oil-water is less than 1.0, the percolation curve is a ＂concave- two-phase relative permeability is affected by core permeability, fluid viscosity, apparent fluidity, and injection drive force; 4） The oil saturation of low- permeability sandstone reservoirs is mostly within 35%-60%, and the oil saturation also has a good positive correlation with the permeability and apparent fluidity.

关键词： Non-Darcy flow relative permeability oil saturation low-permeability sandstone

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AN ANALYSIS ON OUR TRADE EFFECTS OF THE ECO-LABEL SCHEME

AN ANALYSIS ON OUR TRADE EFFECTS OF THE ECO-LABEL SCHEME

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The 14th IGWT Symposium

作者： GAN MINMIN school of environment & natural Resource in renmin university of china beijing 100872

＜正＞The Eco - label scheme roots in people’s awareness of the concept of environmental protection. The paper discusses the eco - label scheme which brings some challenges to our trade and puts forward several countermeasures to its negative effects. At last , the author wants to create the appropriate balance of environment and trade so as to promote sustainable development .

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Oxidation of gaseous elemental mercury in a high voltage discharge reactor

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Journal of environmental Sciences 2009年第12期21卷 1652-1657页

作者： WANG Meiyan, ZHU Tianle, LUO Hongjing, TANG Ping, LI Huan school of Chemistry and environment, Beihang university, beijing 100191, china. [a] school of Chemistry environment Beihang University Beijing 100191 China

Effects of the voltage waveform, discharge tooth wheel number and CO2/NO/SO2 concentration in the simulated flue gas on Hg^0 oxidation were investigated using a link tooth wheel-cylinder reactor energized by different high voltage power supplies. Negative DC discharge induced more ozone production and a higher Hg^0 oxidation efficiency than positive DC discharge and 12 kHz AC discharge. The discharge tooth wheel number had almost no effect on the maximum Hg^0 oxidation efficiency. The allowable supplied voltage decreased with the increase of discharge tooth wheel number. CO2 could stabilize the discharge process and increase the maximum voltage for a stable discharge. It has also been found that NO consumed O3 induced by high voltage discharge, thereby decreased Hg^0 oxidation efficiency; while SO2 had a slight promoting effect on Hg^0 oxidation.

关键词： plasma Hg^0 flue gas oxidation

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ON SYMMETRIC SCALAR CURVAURE ON S^2

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Chinese Annals of Mathematics,Series B 1999年第3期20卷 325-330页

作者： JI MIN(Graduate school at beijing, university of Science and Technology of china, beijing 100039, china.)(Project supported by the National natural Science Foundation of china (No.19631050, No.19725102)and the Foundation of the Ministry of Education of Ch Univ Sci & Technol china Grad Sch Beijing 100039 Peoples R China

Some new results are obtained for the problem of prescribing scalar curvature R on S2 when R possesses some kinds of symmetries.

关键词： Scalar curvature Symmetry Critical point Minimax method

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Simulating the transfer and fate of hexachlorocyclohexane in recent 50 years in beijing, china

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Science china Earth Sciences 2005年第12期48卷 2203-2213页

作者： CAO Hongying1, LIANG Tao1 & TAO Shu2 1. Institute of Geographical Sciences and natural resources Research, Chinese Academy of Sciences, beijing 100101, china 2. Laboratory for Earth Surface Processes, Peking university, beijing 100871, china 1. Institute of Geographical Sciences and natural resources Research Chinese Academy of Sciences 100101 Beijing China 2. Laboratory for Earth Surface Processes Peking University 100871 Beijing China

Taking beijing as a study area, a dynamic fugacity model was used to simulate the transfer and fate of technical HCHs according to the physic-chemical properties of the studying environment and HCH isomers. Dynamic changes of the transfer fluxes and concentrations of HCH isomers during 1952―2003 were simulated and the model results suggest good agreement between the calculated and measured concentrations of HCH isomers. During 1952―1983, the average input and output amount of HCHs through agricultural application and degradation are 130 t and 150 t respectively. The dominant transfer processes of HCHs in the study area are air-soil deposition, soil erosion and soil-air diffusion, transfer fluxes of these processes are 80 t?a?1, 16 t?a?1 and 11 t?a?1, which account for 92% of total transfer fluxes of HCHs isomers. There were approximately 253t HCHs in all environmental compartments of the study area during this period and 97% of which existed in soil compartment. Air and water advection became the dominant input sources of HCHs after 1984 when the application of technical HCHs was prohib-ited, concentration of HCHs quickly descended to a quite low level in several years. Total amount of HCHs isomers remaining in the study area environment now is less than 5% that before 1983, and this percentage may descend to 0.5% after 20 years by prediction.

关键词： fugacity model, hexachlorocyclohexane, compartment, transfer flux, fate.

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