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地理学核心问题与主线——中国地理学会2011年学术年会暨中国科学院新疆生态与地理研究所建所五十年庆典

作者： Guan Liping~(a,b,c) Yang Zhaoping~a (a Xinjiang Institute of Ecology and Geography,CAS, Urumqi,830011 b graduate school of chinese academy of science,beijing 100049 c school of Geographic science and Tourism,Xinjiang Normal University,Urumqi, 830014)

Xinjiang is an exclusive place in the world where the four ancient civilizations of China,Arab,India and Greek *** by mingle of four ancient civilizations,tangible and intangible cultural relics in Xinjiang created the special tourism settings and unique destination for *** arrivals particularly the outbound ones rushing into Xinjiang practice behaviours which bring seriously negative affluences on the cultural heritages in addition to the positive *** an industry, tourism is economically identified;however cultural heritage emphasizes conservation and *** between cultural heritage conservation and tourism development are outstanding obstacle for their sustainable *** key of peaceful solution to conflicts between cultural heritage conservation and tourism development is the cultivation of responsible stakeholders such as community, tour guide,tourists,administrative bodies,*** college education is a distinguished factor in the cultivation of responsible tourism stakeholders and *** paper reviewed some related literatures which stated the importance of college education in the preservation of heritage and their ***,it investigated the situation of college education of tourism in the preservation of cultural heritage in Xinjiang by *** found not a course immediately about relations between cultural heritage and tourism was listed in the curriculums;it failed to inculcate students with awareness of sustainable utilization of cultural heritage as tourism resources;and it did not keep up with the need of tourism development on cultural heritage with rapid expansion but low efficiency and limited improvement in educational *** paper suggested that universities in Xinjiang apply directly related discipline and not just change the existing curriculum structure to extend the channels to meet the needs of the students and society;universities take active part

关键词： responsible college tourism education cultural heritage Xinjiang

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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 school of chinese academy of sciences, beijing 100049 Key Laboratory for Particle Astrophysics Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 and 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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Valuations on arithmetic surfaces

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science China Mathematics 2009年第1期52卷 66-76页

作者： XU Ning Department of Mathematics, graduate school of chinese academy of sciences, beijing 100049, China Department of Mathematics Graduate School of Chinese Academy of Sciences Beijing 100049 China

In this paper, we give the definition of the height of a valuation and the definition of the big field ? p,G , where p is a prime and G ? ? is an additive subgroup containing 1. We conclude that ? p,G is a field and ? p,G is algebraically closed. based on this the author obtains the complete classification of valuations on arithmetic surfaces. Furthermore, for any m ? p,G n ∈ ?, let V m,n be an ∝-vector space of dimension n - m + 1, whose coordinates are indexed from m to n. We generalize the definition of ? p,G , where p is a prime and G ? V m,n is an additive subgroup containing 1. We also conclude that ? p,G is a field if m ? 0 ? n.

关键词： valuation height rank totally ordered group big field transcendental number 14J10

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Adaptive quasi-likelihood estimate in generalized linear models

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science China Mathematics 2005年第6期48卷 829-846页

作者： CHEN Xia & CHEN Xiru school of Mathematics and Statistics, Wuhan University, Wuhan 430072, China graduate school, chinese academy of science, beijing 100049, China 1. school of Mathematics and Statistics Wuhan University 430072 Wuhan China 2. graduate school Chinese Academy of Science 100049 Beijing China

This paper gives a thorough theoretical treatment on the adaptive quasilikelihood estimate of the parameters in the generalized linear models. The unknown covariance matrix of the response variable is estimated by the sample. It is shown that the adaptive estimator defined in this paper is asymptotically most efficient in the sense that it is asymptotic normal, and the covariance matrix of the limit distribution coincides with the one for the quasi-likelihood estimator for the case that the covariance matrix of the response variable is completely known.

关键词： generalized linear models, quasi likelihood estimate, adaptive estimate.

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Infrared Galaxies in the Nearby Universe

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chinese Journal of Astronomy and Astrophysics 2008年第6期8卷 643-652页

作者： Jian-Ling Wang 1 National Astronomical Observatories,chinese academy of sciences,beijing 100012,China 2 graduate school of chinese academy of sciences,beijing 100049,China National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China graduate school of chinese academy of sciences Beijing 100049 China

We used the Sloan Digital Sky Survey （SDSS） Data Release 5 （DR5） to study the morphological properties of 1137 nearby infrared （IR） galaxies, most of which are brighter than 15.9 mag in r-band. This sample was drawn from a cross-correlation of the Infra-Red Astronomical Satellite （IRAS） point source catalog redshift survey with DR5 at z ≤ 0.08. based on this IR galaxy sample, we constructed five volume-limited sub-samples with IR luminosity ranging from 10^9.5 L⊙ to 10^12L⊙. by deriving the IR luminosity functions （LF） for different morphological types, we found that normal spiral galaxies are the dominant population below LIR ~ 8 ~ 10^10 L⊙; while the fraction of barred spiral galaxies increases with increasing IR luminosity and becomes dominant in spiral galaxies beyond LIR ≈ 5 × 10^10L⊙. As the IR luminosity decreases, the IR galaxies become more compact and have lower stellar masses. The analysis also shows that normal spiral galaxies give the dominant contribution to the total comoving IR energy density in the nearby universe, while, in contrast, the contribution from peculiar galaxies is only 39%.

关键词： galaxies evolution galaxies interactions galaxies starburst infrared galaxies galaxies luminosity function

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An Efficient High-Resolution Shock-Capturing Scheme for Multi-Dimensional Flows I. Hydrodynamics

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chinese Journal of Astronomy and Astrophysics 2006年第6期6卷 680-688页

作者： Cong Yu National Astronomical Observatories / Yunnan Astronomical Observatory, chinese academy of sciences, Kunming 650011 graduate school of chinese academy of sciences, beijing 100049 graduate school of chinese academy of sciences Beijing 100049

Many problems at the forefront of theoretical astrophysics require a treatment of dynamical fluid behavior. We present an efficient high-resolution shock-capturing hydrodynamic scheme designed to study such phenomena. We have implemented a weighted, essentially non-oscillatory （WENO） scheme to fifth order accuracy in space, lILLE approximate Riemann solver is used for the flux computation at cell interface, which does not require spectral decomposition into characteristic waves and so is computationally friendly. For time integration we apply a third order total variation diminishing （TVD） Runge-Kutta scheme. Extensive testing and comparison with schemes that *** characteristic decomposition are carried out demonstrating the ability of our scheme to address challenging open questions in astrophysics.

关键词： accretion - hydrodynamics- method numerical - shock waves

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Structure of augmentation quotients of finite homocyclic abelian groups

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science China Mathematics 2007年第9期50卷 1280-1288页

作者： Guo-ping TANG school of Mathematical sciences,graduate University of chinese academy of sciences,beijing 100049,China 1. school of Mathematical sciences Graduate University of Chinese Academy of Sciences Beijing 100049 China

Let G be a finite abelian group and its Sylow p-subgroup a direct product of copies of a cyclic group of order p r , i.e., a finite homocyclic abelian group. Let Δ n (G) denote the n-th power of the augmentation ideal Δ(G) of the integral group ring ?G. The paper gives an explicit structure of the consecutive quotient group Q n (G) = Δ n (G)/Δ n+1(G) for any natural number n and as a consequence settles a problem of Karpilovsky for this particular class of finite abelian groups.

关键词： integral group ring augmentation ideal consecutive quotient of augmentation ideal 16S34 20C05

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A Test on Different Types of the Time Curve of Hardness Ratio of Gamma-Ray bursts based on the Curvature Effect

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chinese Journal of Astronomy and Astrophysics 2008年第4期8卷 451-464页

作者： Lan-Wei Jia National Astronomical Observatories/Yunnan Observatory,chinese academy of sciences,Kunming 650011,China graduate school of chinese academy of sciences,beijing 100049,China National Astronomical Observatories/ Yunnan Observatory Chinese Academy of Sciences Kunming 650011 China and graduate school of chinese academy of sciences Beijing 100049 China

We analyzed a sample of 66 gamma-ray bursts （GRbs） and statistically confirmed the prediction on the time curve of the hardness ratio of GRbs made by Qin et al. based on the curvature effect. In their analysis, GRb pulses are divided into three types according to the shape of their raw hardness ratio （RHR） time curves, defined as to include the background counts to the signal counts, so as to make use of counts within small time intervals. Of the three types, very hard sources exhibit a perfect pulse-like profile （type 1）, hard bursts possess a pulse-like profile with a dip in the decay phase （type 2）, and soft bursts show no pulse-like profile but have only a dipped profile （type 3）. In terms of the conventional hardness ratio, type 3 sources are indeed generally softer than those of type 1 and type 2, in agreement with the prediction. We found that the minimum value of RHR is sensitive in distinguishing the different types. We propose that GRb pulses can be classified according to the minimum value of RHR and that the different type sources may be connected with different strengths of the shock or/and the magnetic field.

关键词： gamma-rays burst -- gamma-rays observations - methods statistical

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A formula on linear complexity of highest coordinate sequences from maximal periodic sequences over Galois rings

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Progress in Natural science:Materials International 2006年第9期16卷 998-1001页

作者： HU Lei and SUN Nigang (State Key Laboratory of Information Security, graduate school of chinese academy of sciences, beijing 100049, China) [a]State Key Laboratory of Information Security Graduate School of Chinese Academy of Sciences Beijing China

Using a polynomial expression of the highest coordinate map, we deduce an exact formula on the linear complexity of the highest coordinate sequence derived from a maximal periodic sequence over an arbitrary Galois ring of characteristic p2 , where p is a prime. This generalizes the known result of Udaya and Siddiqi for the case that the Galois ring is Z4.

关键词： Galois ring highest coordinate sequence linear complexity.

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Existence of unbiased estimate of regression parameters in simple linear EV models

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science China Mathematics 2005年第7期48卷 915-928页

作者： LIU Jixue & CHEN Xiru Department of Statistics and Finance, University of science and Technology of China, Hefei 230026, China Department of Mathematics, graduate school of chinese academy of sciences, beijing 100049, China Department of Statistics and Finance University of Science and Technology of China Hefei 230026 China Department of Mathematics Graduate School Chinese Academy of Sciences Beijing 100049 China

It is well known that for one-dimensional normal EV regression model X = x+ u,Y =α+βx+e, where x, u, e are mutually independent normal variables and Eu=Ee=0, the regression parameters a and β are not identifiable without some restriction imposed on the parameters. This paper discusses the problem of existence of unbiased estimate for a and β under some restrictions commonly used in practice. It is proved that the unbiased estimate does not exist under many such restrictions. We also point out one important case in which the unbiased estimates of a and β exist, and the form of the MVUE of a and β are also given.

关键词： EV regression model unbiased estimate identiflability.

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