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Impact Assessment and Protection of Outstanding Landscape Integrity in a Natural Heritage Site:Fairy Valley,Kanas Nature Reserve,Xinjiang,China

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Journal of Mountain Science 2011年第1期8卷 46-52页

作者： HAN Fang1,2.YANG Zhaoping1,LIU Xinyu1,2.DI Feng3 1 Xinjiang Institute of Ecology and Geography,chinese academy of{2.,Urumqi 830011,China 2.graduate university of chinese academy of{2.,beijing 100049,China 3 Xinjiang Department of Science and Technology,Urumqi 830011,China Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences Urumqi China graduate university of{2. academy of sciences Beijing China Xinjiang Department of Science and Technology Urumqi China

The essential purpose of the Convention Concerning the Protection of World Cultural and Natural Heritage is to protect the integrity of heritage *** landscape is the core embodiment of the aesthetic value of a natural heritage *** paper proposes a new assessment method from the point of view of the protection of heritage *** is used to measure the degree of outstanding landscape integrity under the human and natural impact in natural heritage *** paper employ three indices,a visual index of outstanding landscape,a harmony index of the artificial landscape and a disturbance index of damaged landscape,to measure the impact of landscape *** impact assessment model is based on a weighted combination of the three *** study site is the Fairy Valley,Kanas Nature Reserve,Xinjiang Uygur Autonomous Region in northwest *** information employed is derived from field investigation and a Digital Elevation Model(DEM).A comprehensive evaluation of the Fairy valley was undertaken and it was determined that the outstanding landscape values are being *** protection methods are proposed to reduce the adverse effects and maintain landscape quality,thereby providing site managers with suggestions for the protection of natural heritage *** broadly,the paper contributes novel methods of landscape assessment applicable to natural protected areas.

关键词： Landscape integrity Landscape impact assessment Landscape protection Natural heritage site Kanas Nature Reserve Xinjiang

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The correspondence between the concepts in description logics for contexts and formal concept analysis

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Science China(Information sciences) 2012年第5期55卷 1106-1122页

作者： MA Yue 1,2.SUI YueFei 1 & CAO CunGen 1 1 Key Laboratory of Intelligent Information Processing,Institute of Computing Technology,chinese academy of{2.,beijing 100190,China 2.graduate university of chinese academy of{2.,beijing,China 1. Key Laboratory of Intelligent Information Processing Institute of Computing Technology Chinese Academy of Sciences Beijing 100190 China2. Graduate University of Chinese Academy of Sciences Beijing 100049 China

Formal concept analysis (FCA) and description logic (DL) are meant to be formalizations of concepts.A formal concept in the former consists of its intent and extent,where the intent is the set of all the attributes shared by each object in the extent of the concept,and the extent is the set of all the objects sharing each property in the intent of the concept.A concept in the latter formalization is simply a concept name,the interpretation of which is a subset of a *** consider the correspondence between concepts in both formalizations,a multi-valued formal context must be represented both as a knowledge base and as a model of the DL for contexts,where concepts are decomposed into tuple concepts C,interpreted as a set of tuples and value concepts V,interpreted as a set of attribute-value *** show that there is a difference between the interpretation of concepts R.V /R.C and the Galois connection between the extent/intent of formal concepts in *** to the Galois connection,there should be concepts of the form + R.V and + R.C inter-preted in FCA,and hence the logical language L for DL is extended to be L + together with + as a constructor so that + R.V and + R.C are well-defined ***,according to the interpretation in DL there should be pseudo concepts in FCA so that the interpretation of concepts R.V /R.C is the extent/intent of pseudo *** correspondence between formal concepts and concepts in L +,and between pseudo concepts and concepts in L are presented in this paper.

关键词： description logic formal concept analysis concept attribute/role

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Birthrates and delay times of Type Ia supernovae

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Science China(Physics,Mechanics & Astronomy) 2010年第3期53卷 586-590页

作者： WANG Bo1,2.3, LIU ZhengWei1,2.3, HAN YunKun1,2.3, LEI ZhenXin1,2.3, LUO YangPing1,2.3 & HAN ZhanWen1,2.1National Astronomical Observatories/Yunnan Observatory, chinese academy of{2., Kunming 650011, China 2.ey Laboratory for the Structure and Evolution of Celestial Objects, chinese academy of{2., Kunming 650011, China 3graduate university of chinese academy of{2., beijing 100049, China 1. National Astronomical Observatories/Yunnan Observatory Chinese Academy of Sciences Kunming 650011 China2. Key Laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of Sciences Kunming 650011 China3. Graduate University of Chinese Academy of Sciences Beijing 100049 China

Type Ia supernovae (SNe Ia) play an important role in diverse areas of astrophysics, from the chemical evolution of galaxies to observational cosmology. However, the nature of the progenitors of SNe Ia is still unclear. In this paper, according to a detailed binary population synthesis study, we obtained SN Ia birthrates and delay times from different progenitor models, and compared them with observations. We find that the Galactic SN Ia birthrate from the double-degenerate (DD) model is close to those inferred from observations, while the birthrate from the single-degenerate (SD) model accounts for only about 1/2.2.3 of the observations. If a single starburst is assumed, the distribution of the delay times of SNe Ia from the SD model is a weak bimodality, where the WD + He channel contributes to the SNe Ia with delay times shorter than 100 Myr, and the WD + MS and WD + RG channels to those with age longer than 1 Gyr.

关键词： binaries: close stars: evolution supernovae: general white dwarfs

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Joint source channel VL coding/decoding for deep space communication networks based on a space trellis

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Science China(Information sciences) 2011年第9期54卷 1883-1894页

作者： WU WeiRen 1,TU Juan 2.TU GuoFang 1,GAO ShaoShuai 1 & ZHANG Can 1,3 1 School of Information Science and Engineering,graduate university of{2. academy of sciences,beijing 100049,China 2.beijing Institute of Electronic System Engineering,China Aerospace Science & Industry Corp.,beijing 100854,China 3 State Key Laboratory of Information Security,graduate university of{2. academy of Science,beijing 100049,China 1. School of Information Science and Engineering Graduate University of Chinese Academy of Sciences Beijing 100049 China2. Beijing Institute of Electronic System Engineering China Aerospace Science & Industry Corp. Beijing 100854 China3. State Key Laboratory of Information Security Graduate University of Chinese Academy of Science Beijing 100049 China

This paper presents joint source channel variable length (VL) coding/decoding based on a space *** constructing a joint decoding plane trellis,better decoding performance can be achieved than by using the bit-level decoding ***,the plane trellis is complicated,which results in high decoding complexity for decoding VL turbo *** solve this problem,we construct a space trellis and design a low-complexity joint decoding algorithm with a variable length symbol-a posteriori probability (VLS-APP) algorithm in resource constrained deep space communication *** results show that the proposed approach reduces the decoding complexity by 10% compared with the plane trellis,and the gain of Eb/N0 is about 0.2.dB at SER=***,it provides substantial error protection for variable-length encoded image data.

关键词： joint coding/decoding VL turbo codes space trellis VLS-APP

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ON HOLOMORPHIC CURVES OF CONSTANT CURVATURE IN THE COMPLEX GRASSMANN MANIFOLD G(2.5)

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Acta Mathematica Scientia 2011年第1期31卷 237-248页

作者：焦晓祥彭家贵 Department of Mathematics Graduate University Chinese Academy of Sciences

In this article, it is proved that there doesn’t exist any nonsingular holomorphic sphere in complex Grassmann manifold G（2. 5） with constant curvature k = 4/7, 1/2. 4/9. Thus, from [7] it follows that if φ ： S2.... 详细信息

关键词： Gauss curvature holomorphic curve complex Grassmann manifold

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Synchrotron peak luminosity,black hole mass and Eddington ratio for SDSS flat-spectrum radio quasars

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Science China(Physics,Mechanics & Astronomy) 2010年第S1期53卷 202-206页

作者： GU MinFeng1 & CHEN ZhaoYu1,2.1 Key Laboratory for Research in Galaxies and Cosmology,Shanghai Astronomical Observatory,chinese academy of{2.,Shanghai 2.0030,China 2.graduate university of the chinese academy of sciences,beijing 100049,China 1. Key Laboratory for Research in Galaxies and Cosmology Shanghai Astronomical Observatory Chinese Academy of Sciences Shanghai 200030 China 2. graduate university of the chinese academy of sciences Beijing 100049 China

For a sample of 185 flat-spectrum radio quasars(FSRQs) constructed from the SDSS DR3 quasar catalog,we found a significant correlation between the synchrotron peak luminosity and both the black hole mass and Eddington *** implies that the physics of its jet formation is not only tightly related with the black hole mass,but also with the accretion *** verify that the synchrotron peak luminosity can be a better indicator of jet emission than 5 GHz luminosity,through comparing the relationships between each of these two parameters and both black hole mass and Eddington *** fundamental plane of black hole activity for our FSRQs is established as Lr ∝ L0x.80 ± 0.06 Mbh -0.04 ± 0.09 with a weak dependence on black hole mass,however,the scatter is significant.

关键词： black hole physics galaxies:active galaxies:nuclei quasars:emission lines quasars:general

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Risk Analysis on Groundwater Resources Carrying Capacity Based on Blind Number Theory

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Wuhan university Journal of Natural sciences 2007年第4期12卷 669-676页

作者： ZHANG Ji1,2.YU Sujun31. Key Laboratory of Mountain Hazards and Surface Process,chinese academy of{2./Institute of Mountain Hazards and Environment,chinese academy of{2.,Chengdu 610041,Sichuan,China 2. graduate university of the chinese academy of sciences,beijing 100049,China 3. School of Environmental Science and Engineering,Southwest Jiaotong university,Chengdu 610041,Sichuan,China Key Laboratory of Mountain Hazards and Surface Process Chinese Academy ofSciences/Institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu 610041Sichuan China

Blind numbers of evaluation indices about groundwater resources carrying capacity are defined from the concomitancy of randomness, fuzziness, grey property and unascertainment of groundwater system. Based on fuzzy theory, a comprehensive evaluation model on groundwater resources carrying capacity is constructed with blind information. Then a risk assessment model of surcharge about groundwater resources carrying capacity is established on blind reliability theory. The probable value ＂＊＂ matrix of fuzzy membership degree about carrying capacity corresponding to each judgment level can be obtained with the aid of blind algorithm as well as the subjective reliability ＂×＂ matrix. And then a graph of ＂groundwater carrying capacity v.s. accumulative reliability＂ can be gained Based on the graph, fuzzy membership degree of groundwater resources carrying capacity to each judgment level under different risk probability can be got. Thus, a comparatively reasonable judgment to groundwater resources carrying capacity might be obtained, with comprehensive analysis to the state of society, economy technology and ecology.

关键词： blind number theory groundwater resources carrying capacity evaluation risk analysis

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Preparation and Characterization of Co_(0.3)Cr_(0.7)O_x Particles Using for Thermal Radiation Coating

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稀有金属材料与工程 2012年第S1期41卷 100-103页

作者： Luo Lijie1,2.Huang Chuanbing1,Zhu Yongping1,Zhang Weigang1 1 State Key Laboratory of Multi-phase Complex Systems,Institute of Process Engineering,chinese academy of{2.,beijing 100190,China 2.graduate university of chinese academy of{2.,beijing 100049,China chinese Acad Sci Inst Proc Engn State Key Lab Multiphase Complex Syst Beijing 100190 Peoples R China chinese Acad Sci Grad Univ Beijing 100049 Peoples R China

Novel Co0.3Cr0.7Ox(x=2.3)particles with spinel structure were synthesized via precipitation method through the reactions among CoSO4,Cr(NO3)3 and NaOH solutions,followed by spray-drying and sintering at 12.0 ℃for 4h in the *** particles were characterized by X-ray diffraction(XRD)and scanning electron microscopy(SEM).The XRD results revealed that the particles are composed of Co0.3Cr0.7Ox phase without the presence of other *** SEM observation showed that the particles are in the shape of sphere with well *** radiation test indicated that the total infrared normal emissivity of the coating made of Co0.3Cr0.7Ox can be up to 0.92.at 800℃.And the normal emissivities of the prepared Co0.3Cr0.7Ox particles are always slightly larger than those of CoCr2.4 particles prepared by solid-state reaction method in the test temperature range of 50-300℃.The relatively high thermal emissivity of Co0.3Cr0.7Ox is assumed to be mainly attributed to the spinel *** results indicated that Co0.3Cr0.7Ox particles are a good thermal radiation material,which can be used as infrared radiation layer in thermal protection system.

关键词： Co0.3Cr0.7Ox particles preparation precipitation thermal radiation coating

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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 10002., 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{2. 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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Observation constraints of the hard X-ray modulation telescope HXMT

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Science China(Physics,Mechanics & Astronomy) 2010年第S1期53卷 31-35页

作者： LU Yu1,2.ZHANG WenZhao3,QU JinLu1,SONG LiMing1,GAO Jian3,ZHANG HongMei4 & OU Ge4 1 Key Laboratory of Particle Astrophysics,Institute of High Energy Physics,chinese academy of{2.,beijing 100049,China 2.graduate university of chinese academy of{2.,beijing 100049,China 3 Department of Astronomy,beijing Normal university,beijing 100875,China 4 Computing Center,Institute of High Energy Physics,chinese academy of{2.,beijing 100049,China 1. Key Laboratory of Particle Astrophysics Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 China 2. graduate university of{2. academy of sciences Beijing 100049 China 3. Department of Astronomy Beijing Normal University Beijing 100875 China 4. Computing Center Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 China

The hard X-ray modulation telescope HXMT is a low orbit X-ray space telescope whose main science goals are to accomplish a hard X-ray all sky survey and to study timing and spectral characteristics of X-ray *** has three kinds of science instruments:the high energy X-ray detector(HE),the medium energy X-ray detector(ME) and the low energy X-ray detector(LE).The observation schedule of HXMT is a key to achieving the science goal of HXMT,and the analysis of the observation constraints is one of the first tasks in making the observation *** paper analyzes how the observation constraints influence the sky visibility and the visible time distribution of X-ray sources and discusses the schedule strategy with regard to the observation constraints.

关键词： HXMT observation constraints sky visibility

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