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Representation type of 0-Hecke algebras

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science china Mathematics 2011年第3期54卷 411-420页

作者： DENG BangMing1 & YANG GuiYu2,1Department of Mathematics, beijing normal university, beijing 100875, china 2School of science, Shangdong university of technology, Zibo 255049, china Department of Mathematics Beijing Normal University School of science Shangdong University of Technology

In the present paper we determine the representation type of the 0-Hecke algebra of a finite Coxeter group.

关键词： Coxeter group 0-Hecke algebra representation type

Landscape Change and its effect on the environment of Daqing City

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Progress in Natural science:Materials International 2005年第7期15卷 641-649页

作者： ZANG Shuying, ZHANG Jing and JIA Li ( college of Life and Environment science, Harbin normal university, Harbin 150080, china college of resources Environment & Tourism, Capital normal university, beijing 100037, china college of Economics and Management, Northeast Agricultural university, Harbin 150030, china) college of Life and Environment science Harbin Normal University Harbin 150080 China. college of resources Environment & Tourism Capital Normal University Beijing 100037 China. college of Economics and Management Northeast Agricultural University Harbin 150030 China

In this paper, we will study the temporal-spatial landscape change from 1978 to 2001 in Daqing City, based on the mul- ti spectral scanner (MSS) and thematic mapper (TM) images of remote sensing (RS) of 1978, 1988, 1992, 1996 and 2001. In order to explain the effects of the component change on the whole landscape, we make a statistic analysis about the transfer probability matrix of the component types of the landscape by using the ARCGIS platform through the overlay analysis of different landscape components. Based on the transfer probability matrix, we calculate the in-transfer ratio, the out-transfer ratio and the contributor ratio of the special transfer process of the main landscape components. The results illustrate that the cultivated-land, grassland, swamp, and alkaline land are the main contributors resulting in the landscape change: the out-transfer ratios of grassland and swamp are much higher than the in-transfer ones; the in-transfer ratio of alkaline land is much higher than the out-transfer one; the in-transfer ratio of the land-lot is always higher than its out-transfer with the highest rate per year, although there is a small difference among the in-transfers and the out-transfers per year. The main landscape changing processes are the salination of cultivated-land, salination or desertification of grassland, salination and degeneration of swamp. Results in this paper can provide scientific basis for investigating the landscape change mechanism of resources-based city.

关键词： landscape change environmental effect transfer probability resources-based city.

Synthesis and Structural Characterization of One-dimensional Polynuclear Complex [La(bipyN_2O_2)(TFA)_3]_n

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Chinese Chemical Letters 2000年第10期11卷 935-936页

作者： Wen Xiang ZHU, Yun HE (Department of Chemistry, beijing normal university, beijing 100875) (Department of Pharmacy, beijing Staff Medical college, beijing 100036) Department of Chemistry Beijing Normal University Department of Pharmacy Beijing Staff Medical College

A novel polymeric complex [La(bipyN2O2)(TFA)3]n(TFA= trifluoroacetylacetone) was prepared. The X-ray structure analysis revealed that the complex has an infinite one-dimensional supramolecule structure with the 4,4'-bipyridyl-N,N'-dioxide as a bridge. La(III) is coordinated to eight oxygen atoms, six from three trifluoroacetylacetonate anions, two from two 4,4'-bipyridyl-N,N'-dioxide molecules.

关键词： Lanthanum polynuclear complex trifluoroacetylacetone 4,4'-bipyridyl-N,N'-dioxide.

A New Potent Inhibitor of Thrombin from the Leech Haemendipsa Yanyuanensis

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Journal of Shanghai university(English Edition) 2001年第1期5卷 86-88页

作者： ZHAO Rong le college of Life sciences, beijing normal university, beijing 100875, china college of Life sciences Beijing Normal University Beijing China

Two components of anticoagulant protein were isolated from the leech Haemendipsa yanyuanensis by heparin agarose affinity chromatography and ultracentrifugation. The determination of anticoagulant activity and characterization analysis of the protein using the method of chromogenic substrate indicates that the anticoagulant protein is thrombin specific but not factor Xa specific. The results lay a foundation for the research of the anticoagulant mechanism and application of anticoagulant protein from H. yanyuanensis.

关键词： Heamendipsa yanyuanensis anticoagulant protein thrombin factor Xa

^(14)C dating of moss peat banks in Fildes Peninsula, Antarctica

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Chinese science Bulletin 1999年第19期44卷 1817-1819页

作者： ZHAO Ye and LI RongquanDepartment of Resource and Environmental sciences , beijing normal university , beijing 100875 , china Department of Resource and Environmental sciences Beijing Normal University Beijing China

Based on the radiocarbon data of the moss peat banks in Fildes Peninsula, Antarctica, it was calculated that the mean rates of peat accumulation in the upper layer and the lower layer are 0.195 and 0.069 4 mm·a-1 respectively. Based on the radiocarbon date (3 265 ± 120 aBP) and the mean rate of peat accumulation in the lower peat layer, it was calculated that

关键词： Antarctica moss peat bank 14C dating environmental change.

The minimal genus problem in rational surfaces CP^2#nCP^2

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science china Mathematics 2006年第9期49卷 1275-1283页

作者： ZHAO Xu’an,GAO Hongzhu & QIU Huaidong LMAM,School of Mathematics science, beijing normal university, beijing 100875, china LMAM School of Mathematics Science Beijing Normal University Beijing 100875 China

There are three key ingredients in the study of the minimal genus problem for rational surfaces CP2#nCP2: the generalized adjunction formula, the action of the orthogonal group of the Lorentz space and the geometric construction. In this paper, we prove the uniqueness of the standard form (see Definition 1.1 and Theorem 1.1) of a 2-dimensional homology class under the action of the subgroup of the Lorentz orthogonal group that is realized by the diffeomorphisms of CP2#*** the geometric construction, we determine the minimal genera of some classes (see Theorem 1.2).

关键词： rational surfaces minimal genus Lorentz orthogonal transformation

Lookback time as a test for f(R) gravity in the Palatini approach

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Research in Astronomy and Astrophysics 2011年第11期11卷 1257-1265页

作者： Zhong-Xu Zhai and Wen-Biao Liu Department of Physics, Institute of Theoretical Physics, beijing normal university, beijing 100875, china Department of Physics Institute of Theoretical Physics Beijing Normal University

We use the recently released data of lookback time (LT)-redshift relation, the cosmic microwave background shift parameter and the baryon acoustic oscillation measurements to constrain cosmological parameters of f (R) gravity in the Palatini formalism by considering the f (R) form of type (a) f (R) = R β/Rn and (b) f (R) = R + α ln R β. Under the assumption of a Friedmann-Robertson-Walker universe, we achieved the best fitting results of the free parameters (Ωm0, n) for (a) and (Ωm0, α) for (b). We find that current LT data can provide interesting and effective constraints on gravity models. Compared with other data, the LT constraints favor a smaller value of the non-relativistic matter energy density.

关键词： cosmology cosmic microwave background

Homology classes that can be represented by embedded spheres in rational surfaces

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science china Mathematics 2004年第3期47卷 431-439页

作者： GAO Hongzhu GUO Ren Department of Mathematics,beijing normal university, beijing 100875,china Department of Mathematics Beijing Normal University Beijing China

The problem of embedding spheres in rational surfaces CP 2#n $\overline {CP} $ 2 is studied. For homology classes u = (b 1 + k, b 2,...,b n) with positive self-intersection numbers, a necessary and sufficient conditio... 详细信息

关键词： four manifold embedded sphere self-intersection number

Key technology of mine underground mobile positioning based on LiDAR and coded sequence pattern

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中国有色金属学会会刊：英文版 2011年第S3期21卷 570-576页

作者： WANG Zhi1, 2, WU Li-xin1, 2, LI Hui-ying3 1. college of resources and Civil Engineering, Northeastern university, Shenyang 110004, china 2. Academy of Disaster Reduction and Emergency Management, Ministry of Civil Affairs and Ministry of Education, beijing normal university, beijing 100875, china 3. college of Computer science and technology, Jilin university, Changchun 130012, china college of resources and Civil Engineering Northeastern University Shenyang 110004 China Academy of Disaster Reduction and Emergency Management Ministry of Civil Affairs and Ministry of Education Beijing Normal University Beijing 100875 China college of Computer science and technology Jilin University Changchun 130012 China

Technologies of underground mobile positioning were proposed based on LiDAR data and coded sequence pattern landmarks for mine shafts and tunnels environment to meet the needs of fast and accurate positioning and navigation of equipments in the mine underground without satellite navigation signals. A coded sequence pattern was employed for automatic matching of 3D scans. The methods of SIFT feature, Otsu segmentation and fast hough transformation were described for the identification, positioning and interpretation of the coded sequence patterns, respectively. The POSIT model was presented for speeding up computation of the translation and rotation parameters of LiDAR point data, so as to achieve automatic 3D mapping of mine shafts and tunnels. The moving positioning experiment was applied to evaluating the accuracy of proposed pose estimation method from LiDAR scans and coded sequence pattern landmarks acquired in an indoor environment. The performance was evaluated using ground truth data of the indoor setting so as to measure derivations with six degrees of freedom.

关键词： LiDAR coded sequence pattern mobile positioning SLAM algorithm POSIT algorithm