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A Voronoi-based spatial algebra for spatial relations

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Progress in Natural Science:Materials International 2002年第7期 50-58页

作者： LI Zhilin , ZHAO Renliang and CHEN Jun(1. Department of Land Surveying and Geo-Informatics, The Hong Kong Polytechnic University, Hong Kong, china 2. national Geometries {2. of china, beijing 100044, china) Department of Land Surveying and Geo-Informatics，The Hong Kong Polytechnic University，Hong Kong，china Department of Land Surveying and Geo-Informatics，The Hong Kong Polytechnic University，Hong Kong，china national Geometrics center of{2.，beijing 100044，china national Geometrics center of{2.，beijing 100044，china

Spatial relation between spatial objects is a very important topic for spatial reasoning, query and analysis in geographical information systems (GIS). The most popular models in current use have fundamental deficiencies in theory. In this paper, a generic algebra for spatial relations is presented, in which (i) appropriate operators from set operators (i. e. union, intersection, difference, difference by, symmetric difference, etc. ) are utilized to distinguish the spatial relations between neighboring spatial objects; (ii) three types of values are used for the computational results of set operations-content, dimension and number of connected components; and (iii) a spatial object is treated as a whole but the Voronoi region of an object is employed to enhance its interaction with its neighbours. This algebra overcomes the shortcomings of the existing models and it can effectively describe the relations of spatial objects.

关键词： spatial relations Voronoi-based algebra spatial algebra topological relations.

A 2.0-a record of atmospheric circulation over the North Pacific from a Mt. Logan ice core, Yukon Territory

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Acta Oceanologica Sinica 2005年第4期24卷 81-90页

作者： KANG Shichang MAYEWSKI Paul A YAN Yuping Institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing 100085 China Climate Change Institute University of Maine Orono ME 04469 USA Laboratory of Cryosphere and Environment Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China national Climate center Beijing 100081 China

Calibrations between sodium （Na^＋） concentrations from a Mt. Logan ice core and sea level pressure （SLP） series show that Na^＋ concentrations are closely correlated with the autumn-time （September-October-November） Aleutian low （AleuLow）. A deepening of the AleuLow strengthens the transport of sea-salt aerosols from the North Pacific to the Mt. Logan region. The Mt. Logan Na^＋ record is used to develop a 2.2.a （1688-1979） reconstruction of the AleuLow revealing a dramatic intensification of atmospheric circulation over the North Pacific region since the 2.th century. Mean SLP of the AleuLow was about 1 hPa lower during the 2.th century than during prior periods. The strongest deepening of the AleuLow appeared in the 1950s. Significant correlations are also found between the Mt. Logan AleuLow proxy series and the Pacific decadal oscillation （PDO） and Pacific circulation （PC） index during the 2.th century. Evolutionary spectral analysis of the proxy record shows significant periodicities from 15 to 30 a consistent with PDO fluctuations and the bidecadal oscillation of North Pacific atmosphere-ocean circulation. A period of 11 a in the AleuLow record may be associated with the Schwabe 11-a cycle of sunspot activity. Additional longer ice core records from this region will aid in the efforts to further understand the climatic change over the North Pacific region.

关键词： atmospheric circulation ice core records North Pacific

The Toxicity Evaluation of Recombinant Replicating Vaccinia Virus Vaccine in BALB/c Mice

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The Toxicity Evaluation of Recombinant Replicating Vaccinia ...

Proton induced X-ray emission (PIXE) analysis of sources of porcelain body of Ru Guan and Jun Guan porcelains

第十三届中国科协年会第5分会场-化学物的环境危害与健康风险评估国际研讨会

作者： Sanlong WANG 1 , Limei CAO 1 , Yin LIU 2., Danli DUAN 2., Xiuwen WANG 1 , Bo LI 1 , Yiming SHAO 2.(1. national center for Safety Evaluation of Drugs, national Institute for the Control of Pharmaceutical & Biological Products, Tianjin 300050, china 2. national center for AIDS/STD Prevention and Control, china CDC, beijing 100050, china)

To evaluate the preclinical safety of recombinant replicating vaccinia virus-based HIV vaccines (rVVV)in BALB/c mice. The study was composed of groups 1, 2. 3, 4, wherein the groups 1 and 2.received only one priming immunization and the groups 3, 4 received prime-boost immunizations at a 6-week interval. The dose given was 50μl/skin of back/2.dosing point by intradermal injection approximately 2.2.10 6 PFU. Cellular responses were evaluated in spleenocytes after restimulation on the following basis: detection of IFN-γ producing CD8 + -positive T cells, and CD4 + /CD8 + T cells ratio by FACS assay. Humoral responses were evaluated in serum samples on the basis of specific anti-rVVV antibodies. A real-time quantitative PCR was employed for detection of biodistribution of rVVV in tissues and organs. The results showed that there were no significant toxic effects and damages to major organs in control and rVVV-treated animals. The results of FACS analysis assay for the group 4 that received prime-boost immunization showed cellular immune responses, as indicated by high IFN-γ production by CD8 + -positive T cells. There was no significant change for the CD4 + /CD8 + T cells ratio in control and rVVV-treated animals. Immunogenicity of rVVV given with prime-boost doses was stronger than that of rVVV given with a single priming dose in BALB/c mice. Following intradermal injection of rVVV in mice, all tissues were Q-PCR-negative on Day 35 after dosing. The study showed that there were no significant toxic effects and the rVVV could induce both humoral and cellular immune responses in BALB/c mice.

关键词： Toxicity evaluation Recombinant replicating vaccinia virus Vaccine BALB/c Mice

来源： cnki会议评论

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Science china(Physics,Mechanics & Astronomy) 2006年第4期49卷 411-420页

作者： LI Guoxia1, ZHAO Weijuan1, LI Rongwu2. SUN Hongwei1, GUO Min1, WANG Yanfang1, LIU Hui1, ZHAO Qingyun3, SUN Xinmin3, ZHAO Wenjun3 & CHENG Huansheng4 1. Faculty of Physical Engineering, Zhengzhou University, Zhengzhou 450052. china 2. Department of Physics, beijing Normal University, beijing 100875, china 3. Institute of Cultural Relic and Archaeology of Henan Province, Zhengzhou 450000, china 4. Institute of Modern Physics, Fudan University, Shanghai 2.0433, china Faculty of Physical Engineering Zhengzhou University Zhengzhou 450052 China Department of Physics Beijing Normal University Beijing 100875 China Institute of Cultural Relic Archaeology of Henan Province Zhengzhou 450000 China Institute of Modern Physics Fudan University Shanghai 200433 China

34 samples of Ru Guan porcelain body and 50 samples of Jun Guan porcelain body (both kinds being in different body colors) were selected with the purpose of finding out the source of raw materials and their classification relationship so as to search for ways of non-destructive discrimination. Proton induced X-ray emission (PIXE) has been applied to these samples to determine their chemical elements. The data of seven major chemical elements collected from these samples were further studied through fuzzy cluster analysis. Results indicate that the origin of raw materials of Jun Guan porcelain body samples is comparatively more concentrated in certain places, while that of Ru Guan porcelain body samples is scattered about. The places of origin of raw materials of the majority of Ru Guan and Jun Guan porcelain body samples have something in common, but some differences still exist. It might be an important way for non-destructive discrimination among Ru Guan and Jun Guan porcelains by combining PIXE with fuzzy cluster analysis.

关键词： Ru Guan and Jun Guan porcelain, source of porcelain body, PIXE, fuzzy cluster analysis, non-destructive discrimination.

A primary study of the correlation between the net air-sea heat flux and the interannual variation of western North Pacific tropical cyclone track and intensity

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Acta Oceanologica Sinica 2011年第6期30卷 27-35页

作者： WU Liang WEN Zhiping HUANG Ronghui center for Monsoon and Environment Research/Department of Atmospheric Sciences Sun Yat-sen University Guangzhou 510275 China center for Monsoon System Research Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China

A singular value decomposition （SVD） analysis is carried out to reveal the relationship between the interannual variation of track and intensity of the western North Pacific tropical cyclones （WNPTCs） in the tropical cyclone （TC） active season （July–November） and the global net air-sea heat flux （Q net ） in the preceding season （April–June）. For this purpose, a tropical cyclone track and intensity function （TIF） is defined by a combination of accumulated cyclone energy （ACE） index and a cyclone track density function. The SVD analysis reveals that the first mode is responsible for the positive correlation between the upward heat flux in the tropical central Pacific and the increased activity of western North Pacific （WNP） TIF, the second mode for the positive correlation between the upward heat flux in the North Indian Ocean and the northeastward track shift of WNPTCs and the third mode for the negative correlation between the upward heat flux in mid-latitude central Pacific and the northwest displacement of the WNP TC-active {2.. This suggests that Q net anomalies in some key regions have a substantial remote impact on the WNP TC activity.

关键词： tropical cyclone western North Pacific the net air-sea heat flux (Q net ) interannual variation

Hard X-ray lags of Cygnus X-1 on short timescales

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Science china(Physics,Mechanics & Astronomy) 2010年第S1期53卷 150-152页

作者： JIN Jing1,LU Yu2.3,QU JinLu2.& LI TiPei1,2.1 Department of Engineering Physics & center for Astrophysics,Tsinghua University,beijing 100084,{2. 2.Key Laboratory of Particle Astrophysics,Institute of High Energy Physics,Chinese Academy of Sciences,beijing 100049,{2. 3 Graduate University of Chinese Academy of Sciences,beijing 100049,{2. 1. Department of Engineering Physics & center for Astrophysics Tsinghua University Beijing 100084 China2. Key Laboratory of Particle Astrophysics Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 China3. Graduate University of Chinese Academy of Sciences Beijing 100049 China

Calculating the time lags over different timescales using the cross-correlation technique may lead to a biased estimate of small *** a timescale for lightcurve binning,we propose to subtract the local average instead of the global average during the cross-correlation,in order to filter variations on timescales larger than the bin *** new method allows us to make an unbiased estimate of the time lags using RXTE/PCA data on timescales as small as-5 ms,where the Fourier technique becomes *** calculate the time lag spectra of Cygnus X-1 at different spectral states with the new method,and find that the source appears to have similar X-ray lags on small timescales independent of its spectral states.

关键词： spectral lags Cygnus X-1 data analysis

Thresholds of geographic environmental elements in sediment yield of drainage basins

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Science china Earth Sciences 2005年第2期48卷 230-240页

作者： CHEN Hao, ZHOU Jinxing, CAI Qiangguo, LU Zhongchen & LI Zhongyan Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, beijing 100101, china Institute of Forestry Science, Chinese Academy of Forestry Science, beijing 100091, china Research center for Eco-Environment Sciences, Chinese Academy of Sciences, beijing 100085, china Computing Institute of Science and Engineering, North china Electric Power University, beijing 102.06, china 1. Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences 100101 Beijing China 2. Institute of Forestry Science Chinese Academy of Forestry Science 100091 Beijing China 3. Research center for Eco-Environment Sciences Chinese Academy of Sciences 100085 Beijing China 4. Computing Institute of Science and Engineering North China Electric Power University 102206 Beijing China

Threshold of environmental elements in drainage basin sediment yield refers to, under effect of climate, underlying surface and human activity, a turning point of abrupt changes in drainage sediment yield related to environmental element characteristics. Previous studies on threshold of sediment yield of relevant drainage basins were mainly concentrated on impact of natural zones with a few researches on impact of other environmental elements. Particularly studies on compound environmental element threshold in drainage basin sediment yield remain blank today. Studies indicate that sediment yield in drainage basins is affected by compound interactions and complex actions. Based on single element analysis, the present paper gives quantitatively compound threshold of environmental elements affecting sediment yield of the drainage basin between Hekouzhen and Tongguan in the middle Yellow River by the method of multi-variant, polynomial formula regression analysis.

关键词： middle Yellow River, environmental element, sediment, sediment delivery mudule, threshold.

Contemporary crustal movement of continental china obtained by global positioning system(GPS) measurements

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Chinese Science Bulletin 2001年第18期46卷 1552-1554,1588页

We obtain a unified horizontal velocity field of continental china and vicinity through measurements at 81 GPS stations provided by the national Key Infrastructure Project, Crustal Movement Observation Network of china. The velocity field delineates patterns of movements and deformation of active crustal blocks in continental china under the Eurasia-fixed reference frame. The space-based geodesy also clearly shows for the first time the horizontal movementand deformation of continental china induced by indentation of the Indian plate. The data provide kinematic constraints for simulating dynamic process of continental litho-spheric deformation.

关键词： crustal movement velocity field tectonic deformation.

The effectiveness assessment of gas accumulation processes in Kuqa depression,Tarim Basin,Northwest china

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Science china Earth Sciences 2008年第S2期51卷 117-125页

作者： LIU GuangDi1,SUN MingLiang1,L YanFang2.& SUN YongHe2.1 State Key Laboratory of Petroleum Resource and Prospecting,china University of Petroleum,beijing 102.49,china 2.Daqing Institute of Petroleum,Daqing 163318,china china Univ Petr State Key Lab Petr Resource & Prospecting Beijing 102249 Peoples R China Daqing Inst Petr Daqing 163318 Peoples R China

The effectiveness of gas accumulation processes is controlled by several main geological factors in-cluding charging force,features of gas conduit,sealing properties of caprock,etc. Based on the analysis and statistics of the large-medium size gas accumulations in{2.,the main parameters,in-cluding the excess pressure difference between the source rock and reservoir bed,the area coefficient of the gas conduit,and the thickness or displacement pressure of caprock,and the criteria for the as-sessment of gas accumulation processes have been established. Using the parameters and the criteria above,the effectiveness of gas accumulation processes in the Kuqa depression was quantitatively evaluated. By integrating the parameters of the excess pressure difference between the source rock and reservoir bed,the area coefficient of fault conduit system,and the caprock thickness in gas charging period,a comprehensive assessment of the effectiveness of gas accumulation in the Kuqa depression has been made. The result reveals that the Tubei-Dawan area,the Central Kelasu area and the Dongqiu-Dina area are three highly-effective areas for gas accumulation in the Kuqa depression.

关键词： accumulation process conduit system abnormal pressure caprock play assessment Kuqa depression