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Positioning localities from spatial assertions based on Voronoi neighboring

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science china(Technological sciences) 2010年第S1期53卷 143-149页

作者： GONG YongXi 1,2.3,LI GuiCai 1,LIU Yu 2.& YANG Jian 1 1 shenzhen Key lab of Recycling Economy,Peking university shenzhen Graduate school,shenzhen 518055,{2. 2.nstitute of Remote sensing and geographical Information systems,Peking university,beijing 100871,{2. 3College of Urban and Environmental science,Peking university,beijing 100871,{2. Peking Univ Shenzhen Grad Sch Shenzhen Key Lab Recycling Econ Shenzhen 518055 Peoples R China Peking Univ Inst Remote Sensing & Geog Informat Syst Beijing 100871 Peoples R China Peking Univ Coll Urban & Environm Sci Beijing 100871 Peoples R China

With the rapid development of Internet,much spatial information contained in non-structured or semi-structured documents is available on the World Wide *** such documents,localities are always textually described using spatial relationships and named places,instead of numerical ***,extracting positional information from locality descriptions is an important *** this paper,we bridge two aspects of locality descriptions,namely generating locality descriptions and positioning localities,and provide a method to compute probability density according to the selection probability of a reference object to describe the position of the target *** operation on uncertainty field is used to deal with locality description involving multiple reference *** metrics are introduced to measure the results of positioning *** choose the mixed selection probability function based on Euclidean distance and Voronoi stolen-area to compute probability density ***,we use three cases to demonstrate the proposed methods.

关键词： geographic information science positioning locality Voronoi neighboring probability density function

A distributed hydrological model with its application to the Jinghe watershed in the Yellow River Basin

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science china(Technological sciences) 2004年第z1期47卷 60-71页

作者： WANG Zhonggen1, ZHENG Hongxing1, LIU Changming1, , WU Xianfeng2.2.& ZHAO Weimin3 1. Key laboratory of Water Cycle & Related Land surface Processes, Institute of geographic science and Natural Resources Research, Chinese Academy of sciences, {2. 100101, china 2. Institute of Environmental science, {2. Normal university, {2. 100875, china 3. Water Resources Conservation Committee of Yellow River, Zhengzhou 450003, china Chinese Acad sci Key Lab Water Cycle & Related Land Surface Proc Inst Geog Sci & Nat Resources Res Beijing 100101 Peoples R China beijing Normal Univ Inst Environm Sci Beijing 100875 Peoples R China Water Resources Conservat Comm Yellow River Zhengzhou 450003 Peoples R China

For the purpose of water resources management in the Yellow River Basin with highly spatial difference, a daily distributed hydrological model was proposed, of which the determination of spatially-distributed parameters and model inputs processing were performed by means of GIs/Rs. In the model, the computation of runoff yield was based on the topography index method and flow routing was modeled by Maskingum method. The operation of the model is followed by means of “command structure” technique based upon the topography of river network. A case study using the model was conducted for the Jinghe watershed, which locates at the middle Yellow River Basin. The simulation of the hydrological processes in 1996 has shown that water quantity balance errors were less than 5% and the Nash-sutcliffe coefficient arrived at 0.7, indicating that the model structure is justifiable, and the precision of the model can satisfy the purpose of water resources management.

关键词： distributed hydrological model, structure and equation, GIs and Rs, Jinghe Basin, Yellow River Basin.

A hydrocarbon enrichment model and prediction of favorable accumulation areas in complicated superimposed basins in china

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Petroleum science 2010年第1期7卷 10-19页

作者： Pang Xiongqi Meng Qingyang Jiang Zhenxue Liu Luofu Lu Xiuxiang state Key laboratory of Petroleum Resources and Prospecting China University of Petroleum Beijing 102249 China Basin and Reservoir Research center China University of Petroleum Beijing 102249 China Research Institute of Petroleum Exploration and Development PetroChina Beijing 100083 China

The geologic conditions of superimposed basins in china are very complicated. This is mainly shown by multi-phase structural evolution, multiple sets of source-reservoir-cap rock combinations, multiple stages of hydrocarbon generation and expulsion from source rocks, multi-cycle hydrocarbon enrichment and accumulation, and multi-phase reservoir adjustment and reconstruction. The enrichment, accumulation and distribution of hydrocarbon is mainly controlled by the source rock kitchen, paleo- anticline, regional cap rock and intensity of tectonic movement. In this paper, the T-BCMs model has been developed to predict favorable areas of hydrocarbon accumulation in complicated superimposed basins according to time and spatial relationships among five key factors. The five factors include unconformity surface representing tectonic balancing （B）, regional cap rock representing hydrocarbon protection （C）, paleo-anticline representing hydrocarbon migration and accumulation （M）, source rock kitchen representing hydrocarbon generation and expulsion （s） and {2. time （T）. There are three necessary conditions to form favorable areas of hydrocarbon accumulation. First, four key factors BCMs should be strictly in the order of BCMs from top to bottom. second, superimposition of four key factors BCMs in the same area is the most favorable for hydrocarbon accumulation. Third, vertically ordered combination and superimposition in the same area of BCMs should occur at the same {2. time. The model has been used to predict the most favorable exploration areas in Ordovician in the Tarim Basin in the main hydrocarbon accumulation periods. The result shows that 95% of the discovered Ordovician hydrocarbon reservoirs are located in the predicted areas, which indicates the feasibility and reliability of the key factor matching T-BCMs model for hydrocarbon accumulation and enrichment.

关键词： Complicated superimposed basin key factor matching T-BCMs model favorable area for hydrocarbon accumulation hydrocarbon distribution prediction

Discovery of double-peaking potassic volcanic rocks in Langshan Group of the Tanyaokou hydrothermal- sedimentary deposit, Inner Mongolia, and its indicating significance

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science china Earth sciences 2005年第6期48卷 822-833页

作者： PENG Runmin1, ZHAI Yusheng1, WANG Zhigang2.& HAN Xuefeng2.1. Key laboratory of Lithospheric Tectonics and Lithoprobing Technology, Ministry of Education, china {2. of {3.sciences, beijing 100083. china 2. Inner Mongolia geological Prospecting Institute, Ministry of Chemical Industry, Hohhot 010074, china Correspondences should be addressed to Peng Runmin 1. Key laboratory of Lithospheric Tectonics and Lithoprobing Technology Ministry of Education China University of Geosciences 100083 Beijing China 2. Inner Mongolia geological Prospecting Institute Ministry of Chemical Industry 010074 Hohhot China

It is revealed that the protolith of gray-light brown potash-feldspar-leucogranulites and granulites in the 2.d formation of the LG in Tanyaokou deposit are quartz kerotophyre of synsedimentary eruption based on the following facts and features: (1) The rocks look compact and homogeneous without obvious crystals with naked eyes; (2. they contain blastoporphyritic or glomeroporphyritic and blasto-crystalloclastic crystals consisting of quartz with wavy extinction and albite with obvious alteration and deformation; (3) they also contain radiated and fibrous blasto-microspherulitic texture and swallow-tailed bifurcate and blasto-hollow-skeleton crystal texture, representing the rapid cooling characteristic of the magma during submarine volcanic eruption; (4) the major chemical compositions of the rocks are: siO2.= 70.80%―76.00%, K2. (4.83%―6.2.%)>Na2.(2.78%―3.80%), and K2.+Na2. = 8.63%―9.00%; and (5) their petro-chemical diagrams indicate that they are volcanic rocks. Together with the characteristic that they occur in the same sequence with potassic spilite (siO2.= 46.12.―50.68%, K2. = 4.2.%―5.93%>Na2. = 2.15%―3.14%, K2.+Na2. = 6.51%―8.08%), it can be confirmed that the vol-canics occurring in the 2.d Formation of the LG in Tanyaokou district are double-peaking potas-sic volcanic rocks. The discovery, together with the tuffs with ore minerals and the distribution of lead isotopic as well as the value of Co/Ni of pyrites >1 showing the obvious endogenic metali-zation, can prove that the Tanyaokou deposit is an untypical sEDEX-type deposit formed in the extension fault basin in the Mesoproterozonic aulacogen of the northern margin of the North china Platform, and its metallogenesis is related to the synsedimentary volcanic activities and the hydrothermal exhalation, and both the ore-forming material source and volcanics came from mantle or lower crust. These facts mentioned above, together with the meta-volcanic rocks (double-peaking) found in the Dongshengmiao and Huog

关键词： extensional rift basin, double-peaking potassic volcanic rocks, Mesoproterozoic, the 2.d formation of LG, Tanyaokou deposit, Inner Mongolia.

Investigation of Al-based Alloys for Brazing siC_p/Al Composites

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稀有金属材料与工程 2011年第S3期40卷 132-135页

作者： Wu Mao1,2. Chang Lingling2. Peng Zirong2. Feng Zelong2. Yong Weina2. Wang Wei2. He Xinbo1,2. Qu Xuanhui1,2.1state Key laboratory for Advanced Metals and Materials, university of science and Technology{2. 2.beijing Key laboratory for Powder Metallurgy and Particulate Materials, university of science and Technology beijing,{2. Univ sci & Technol beijing State Key Lab Adv Met & Mat Beijing 100083 Peoples R China Univ sci & Technol beijing Beijing Key Lab Powder Met & Particulate Mat Beijing 100083 Peoples R China

The brazing of siCp/Al composites is limited owing to the unavailability of suitable commercial intermediate temperature brazes. Adding a third constituent of copper to aluminum-silicon brazing alloy can depress the melting point sharply. While, it generates a large volume fraction of the hard Al2.u intermetallic compounds (IMCs), which makes the alloy brittle and reduces its corrosion resistance. A quaternary addition of nickel that partly substitute for copper can refine grain size significantly, improve the mechanical properties, and without altering the melting range of aluminum-silicon-copper alloy. Al-Cu-Ni-si braze alloy has been prepared and a fluxless process has been employed to braze siCp/Al composites that leads to a good bonding strength of brazing joint.

关键词： siCp/Al composites Al-based brazes brazing intermetallic compounds (IMCs)

Effect of Carbon on Dynamic Recrystallization Behavior of Vanadium Microalloy steels

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Journal of Iron and steel Research International 2011年第S1期18卷 129-134页

作者： LIU Guo-quan 1,2.ZHAO Hai-tao 1,WU Jin-bin 1,WANG Cheng-yang 1,XU Lei 1,3 (1.school of Materials science and Engineering,university of science and Technology beijing,beijing 100083.china 2.state Key laboratory for Advanced Metals and Materials,university of science and Technology beijing,beijing 100083.china 3.Department of Materials science and Engineering,Tsinghua university,beijing 100084,china) Univ sci & Technol beijing Sch Mat Sci & Engn Beijing 100083 Peoples R China Univ sci & Technol beijing State Key Lab Adv Met & Mat Beijing 100083 Peoples R China Tsinghua Univ Dept Mat Sci & Engn Beijing 100084 Peoples R China

The hot working behavior especially dynamic recrystallization of low-carbon and medium-carbon vanadium microalloy steels has been studied by performing isothermally compression tests and Avrami *** Avrami plots of the two experiment steels have been constructed based on flow stress curves following a new approach (Jonas,et *** Mater.,2.09,57(2.:2.48-2.56;Wu et al,Acta ***.,2.10,46(7):838-843).It is experimentally found that the carbon effect on dynamic recrystallization is opposite to each other in lower and higher strain ranges:Carbon causes a softening effect at low strain rates (0.01,0.1,and 1.0 s-1),and a hardening effect at high strain rates (10.0 and 30.0 s-1).Correspondingly,carbon promotes the dynamic recrystallization at low strain rates and retards the dynamic recrystallization at high strain rates in the experimental *** phenomenon is then tentatively explained based on the possible mechanisms of dynamic process at different strain rates.

关键词： vanadium microalloy steels hot working dynamic recrystallization carbon strain rate Avrami modeling

Environmental characteristics of Mid-Holocene recorded by lacustrine sediments from Lake Daihai, north environment sensitive zone, china

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science china Earth sciences 2006年第9期49卷 968-981页

作者： sUN Qianli1,2. ZHOU Jie1, sHEN Ji3, CHEN Peng1,2. WU Feng1,2.& XIE Xiuping1,2.1. state Key lab of Loess and Quaternary geology, Institute of Earth Environment, Chinese Academy of sciences, Xi’an 710075, {2. 2. Graduate university of Chinese Academy of sciences, beijing 100039, {2. 3. Nanjing Institute of geography and Limnology, Chinese Academy of sciences, Nanjing 2.0008, {2. 1. state Key lab of Loess and Quaternary geology Institute of Earth Environment Chinese Academy of Sciences Xi’an 710075 China 2. Graduate university of Chinese Academy of sciences Beijing 100039 China 3. Nanjing Institute of geography and Limnology Chinese Academy of Sciences Nanjing 210008 China

Climate proxies, such as total organic carbon and nitrogen (TOC, TN), carbonate content (CaCO3), grain-size and pollen of the sediment core retrieved from enclosed Lake Daihai which lies in the north china environment sensitive zone are analyzed to reconstruct the environment evolution of the area based on high-resolution radiocarbon chronology. The results reveal that the TOC and TN contents of the sediments correlate well with pollen percentage and pollen flux variations during the Holocene, and both reach their peak values simultaneously at 6.7―3.5 ka BP (calendar age, 7.6―3.6 ka BP). since 6.7 ka BP, both the CaCO3 and organic matter contents of the core have simultaneous variations, and their high values also occur during 6.7―3.5 ka BP. While during 9.0―6.7 ka BP (calendar age, 10―7.6 ka BP) relatively lower level of organic matter content and pollen flux corre- spond to the higher level of carbonate content. The above relations suggest that during 6.7―3.5 ka BP, the productivity and effective precipitation were greatly improved in the lake drainage area, and this would probably strengthen the hydrodynamic conditions, enhancing organic matter, pollen and carbonate inputs from terrestrial sources. such processes would account for the enrichment of both organic matter and carbonate in the sediments. While during 9.0―6.7 ka BP, the lower level of or- ganic matter, pollen flux but high carbonate content show depressed productivity and declined vege- tation coverage. The higher carbonate content at this stage would have probably resulted from the higher evaporation ratio of the lake water under relatively drier climate conditions. Therefore, it is in- ferred that during 6.7―3.5 ka BP, the climate was more humid with abundant rainfalls and vegetation was more flourishing in the Lake Daihai area. This can be seen as Holocene Climate Optimum (HCO). As a result, this has evident discrepancies with the traditional notion that the HCO occurs at Early Holocene or early Mid

关键词： Lake Daihai, Mid-Holocene, lacustrine sediments, environmental characteristics.

Macro-and microscopic mechanical behaviour of flow of coal samples experimentally deformed at high temperatures and pressures

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Chinese science Bulletin 2005年第S1期50卷 59-66页

作者： LIU Junlai , YANG Guang & MA Rui state Key laboratory of geological Processes and Mineral Resources, {2. university of geosciences, beijing 100083. china Key laboratory of Lithosphere Tectonics and Lithoprobing Technology of Ministry of Education, {2. university of geosciences, beijing 100083. china College of Earth sciences, Jilin university, Changchun 130061, {2. china Univ geosci State Key Lab Geol Proc & Mineral Resources Beijing 100083 Peoples R China china Univ geosci Minist Educ Key Lab Lithosphere Tecton & Lithoprobing Technol Beijing 100083 Peoples R China Jilin Univ Coll Earth Sci Changchun 130061 Peoples R China

Coal samples from Qinshui Basin, shanxi, china are experimentally deformed at temperatures and confining pressures of 2.0 - 500℃and 2.0 - 500 Mpa, strain rate of 0.5×10-5/s and total strain of 10%. The vitrinite reflectance of the coal samples varies from 3.04 to 1.79. It is shown that the strengths of the deformed samples change obviously with coeval increasing temperatures and pressures (T/P). At the experimental range of T/P, the effects of increasing temperature predominate over that of increasing pressure. Microstructural analysis indicates a brittle to ductile transition under experimental T/P conditions from 2.0 to 300℃, and 2.0 to 300Mpa. Brittle deformation microstruc-tures include macroscopic fracture zones and penetrative fracture associations. Elongation, undulose or irregular extinction, deformation lamellae and dynamic recrystallization of grains are the main ductile deformation microstructures. The variation of deformation mechanisms of the experimentally deformed coal samples is related to both the components of coals and T/P conditions. At low T/P, fractures occur in both inertinite and vitrinite of the samples. At higher T/P, crystalline plastic deformations are observed in the inertinite only.

关键词： coal experimental deformation brittle to ductile transition.

Metallogenic characteristics of epithermal gold deposits in Tianshan, Xinjiang, china

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Chinese science Bulletin 1999年第S2期44卷 138-139页

作者： FENG Jianzhong~1, FU shuixing~2. WU Dewen~3 and YANG Zian~3 1. Department of geology, Peking university, {2. 100871, china 2. {2. Institute of geology for Mineral Resources, {2. 100012. china 3. center of Remote sensing for geology, CNNC, {2. 101601, china Department of geology Peking University Beijing 100871 China beijing Institute of geology for Mineral Resources Beijing 100012 China center of Remote sensing for geology CNNC Beijing 101601 China

TIANsHAN in southern Xinjiang belongs to the Paleozoic island arc system in which volcanic rocks are extensively distributed. A series of epithermal gold deposits such as the Axi, Xitan, Cuiling andshuangfengshan gold deposits have been discovered. 1 geological settings of epithermal gold deposits in Tianshan, southern Xinjiang Tianshan in southern Xinjiang belongs to the Paleozoic island arc system. To its north is the Kazakhstan plate, and to its north is the Tarim plate. From west to east, the tectonic units are characterizedby Yili island arc, southern Tianshan arc-basin, Jiaoluotage island arc and Xingxingxia island arc. TheEW-trending Tianshan ore belt is controlled by Kanggurtag geosuture. In its west part, it is controlled byshenglidaban geosuture. The linear structure is NNW-trending; from north to south, the faults

关键词： metallogenic characteristics gold deposits Tianshan Xinjiang.