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Wuhan university Journal of Natural Sciences 2006年第4期11卷 1046-1051页

作者： CHEN Guangjian 1, 2. 3 , LIU Qing 1 1. Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu 610041, Sichuan,china 2. graduate {2. of Chinese Academy of Sciences, beijing 100049, china 3. Academy of Land Reconnaissance and Layout of Sichuan Province , Chengdu 610031, Sichuan, china Chengdu Institute of Biology Chinese Academy of Sciences Chengdu Sichuan China graduate university of Chinese Academy of Sciences Beijing China Academy of Land Reconnaissance and Layout of Sichuan Province Chengdu Sichuan China

This paper established sustainable land resources evaluating indicators fit for hilly area in Sichuan Basin, Southwest of china, and evaluated the case of sustainable land management of Lezhi County from 1990 to 2.01. The result showed that the land resource sustainable utilization ability in Lezhi County is belong to Second level （better sustainable）. Secondly, this paper diagnosed some years obstacles of sustainable land management of Lezhi County from base period to goal period and compared the obstacles factors in the indicators system. There were 16 indexes orderly become major affect factor to land sustainable utilization of Lezhi county in indicator system, of which there are 8 obstacles indexes exist both in 1990 and 2.01. The value of obstacles degree of five indicators exceeded 5 in 1990, but in 2.01, only two indicators＇ values were more than 5.

关键词： land resources sustainable land management assessment indicators diagnosis of obstacle

Simulations for terrestrial planets formation

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Science china(Physics,Mechanics & Astronomy) 2009年第5期52卷 794-803页

作者： ZHANG Niu 1,2.&JI JiangHui 2.3 1graduate university of Chinese Academy of Sciences,{2. 100049,china 2.urple Mountain Observatory,Chinese Academy of Sciences,Nanjing 2.0008,china 3 National Astronomical Observatories,Chinese Academy of Sciences,{2. 100012.china graduate university of Chinese Academy of Sciences Beijing 100049 China Purple Mountain Observatory Chinese Academy of Sciences Nanjing 210008 China National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China

In this paper,the formation of terrestrial planets in the late stage of planetary formation is investigated using the two-planet *** that time,the protostar formed for about 3 Ma and the gas disk *** the model,the perturbations from Jupiter and Saturn are *** of the mass of outer planet,and the initial eccentricities and inclinations of embryos and planetesimals are also *** results show that,terrestrial planets are formed in 50 Ma,and the accretion rate is about 60%-80%.In each simulation,3-4 terrestrial planets are formed inside"Jupiter"with masses of 0.15 -3.6M⊕.In the 0.5-4 AU,when the eccentricities of planetesimals are excited,planetesimals are able to accrete material from wide radial *** plenty of water material of the terrestrial planet in the Habitable Zone may be transferred from the farther places by this *** could also happen a few times between two major planets only if the outer planet has a moderate mass and the small terrestrial planet could survive at some resonances over time scale of 10 8 *** one of our simulations,commensurability of the orbital periods of planets is very ***,a librating-circulating 3:2.configuration of mean motion resonance is found.

关键词： astrophysics exoplanet planetary formation n-body simulation

^(13)C NMR spectra of tectonic coals and the effects of stress on structural components

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Science china Earth Sciences 2005年第9期48卷 1418-1437页

作者： JU Yiwen1,2. JIANG Bo1, HOU Quanlin2. WANG Guiliang1 & NI Shanqin2.1. College of Mineral Resource and Geosciences, china university of Mining and Technology, Xuzhou 2.1008, china 2. Laboratory of Computational Geodynamics, College of Geosciences, graduate School of Chinese Academy of Sciences, beijing 100049, china 1. College of Mineral Resource and Geosciences China University of Mining and Technology 221008 Xuzhou China 2. Laboratory of Computational Geodynamics College of Geosciences Graduate School of Chinese Academy of Sciences 100049 Beijing China

High-resolution 13C Nuclear Magnetic Resonance (NMR) spectra of different kinds of tectonic coals were obtained using the NMR (CP/MAS+TOSS) method. On the basis of this, after simulation synthesis and division of spectra, the relative contents of carbon functional groups were calculated. Combined with results of Ro, max, XRD testing and element analysis, stress effects on the composition of macromolecular structures in tectonic coals were studied further. The results showed that Ro, max was not only the important index for describing coal rank, but was also effective for estimating the stress effect of tectonic coals. Under tectonic stress ac- tion, Ro, max was the most direct indicator of the coal structure and chemical components. Changes in the stacking Lc of the coal basic structure unit (BSU) and La/Lc parameters could distinguish the temperature and stress effects on metamorphic-deformed environments, and re- flected the degree of structural deformation. Therefore, on the whole, Lc and La/Lc can be used to index of the degree of structural deformation of tectonic coals. In different metamorphic and de- formed environments, different kinds of tectonic coals are formed under structural stress. The changes in characteristics of the macromolecular structure and chemical composition are such that as the increase in structural deformation becomes stronger, from the brittle deformation coal to ductile deformation coal, the ratio of width at the half height of the aromatic carbon and ali- phatic carbon peaks (Hfa/Hfal ) was increased. As carbon aromaticity was raised further, carbon aliphaticity reduced obviously and different compositions of macromolecular structure appeared as a jump and wave pattern except for in wrinkle structure coal, which might result chiefly from stress effects on the macromolecular structure of different kinds of tectonic coals. The macro- moecular changes of wrinkle structure coal are reflected mainly on physical structure. In the metamorphi

关键词： tectonic coal, NMR, macromolecular structure, chemical component, stress effect.

Polynomial regression calculation of the Earth's position based on millisecond pulsar timing

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Research in Astronomy and Astrophysics 2012年第2期12卷 219-234页

作者： Feng Tian 1,2.Zheng-Hong Tang 1,Qing-Zeng Yan 1,2.and Yong Yu 11 Shanghai Astronomical Observatory,Chinese Academy of Sciences,Shanghai 2.0030,china 2.graduate {2. of Chinese Academy of Sciences,beijing 100049,china Shanghai Astronomical Observatory Chinese Academy of Sciences Shanghai 200030 China graduate university of Chinese Academy of Sciences Beijing 100049 China

Prior to achieving high precision navigation of a spacecraft using X-ray observations, a pulsar rotation model must be built and analysis of the precise posi- tion of the Earth should be performed using ground pulsar timing observations. We can simulate time-of-arrival ground observation data close to actual observed values before using pulsar timing observation data. Considering the correlation between the Earth＇s position and its short arc section of an orbit, we use polynomial regression to build the correlation. Regression coefficients can be calculated using the least square method, and a coordinate component series can also be obtained; that is, we can calcu- late Earth＇s position in the Barycentric Celestial Reference System according to pulse arrival time data and a precise pulsar rotation model. In order to set appropriate param- eters before the actual timing observations for Earth positioning, we can calculate the influence of the spatial distribution of pulsars on errors in the positioning result and the influence of error source variation on positioning by simulation. It is significant that the threshold values of the observation and systematic errors can be established before an actual observation occurs; namely, we can determine the observation mode with small errors and reject the observed data with big errors, thus improving the positioning result.

关键词： autonomous positioning - millisecond pulsar - pulsar timing - re-gression analysis

Gasdynamic characteristics of toroidal shock and detonation wave converging

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Science china(Physics,Mechanics & Astronomy) 2005年第6期48卷 739-749页

作者： TENG Honghui1,2.& JIANG Zonglin2.1. Key Laboratory of High Temperature Gas Dynamics, Institute of Mechanics, Chinese Academy of Sci- ences, beijing 100080, china 2. {2. university of Chinese Academy of Sciences, beijing 100039, china 1. Key Laboratory of High Temperature Gas Dynamics Institute of Mechanics Chinese Academy of Sciences 100080 Beijing China 2. graduate university of Chinese Academy of Sciences 100039 Beijing China

The modified CCW relation is applied to analyzing the shock, detonation wave converging and the role of chemical reactions in the process. Results indicate that the shock wave is strengthened faster than the detonation wave in the converging at the same initial Mach number. Euler equations implemented with a detailed chemical reaction model are solved to simulate toroidal shock and detonation wave converging. Gasdynamic characteristics of the converging are investigated, including wave interaction patterns, observable discrepancies and physical phenomena behind them. By comparing wave diffractions, converging processes and pressure evolutions in the focusing area, the different effects of chemical reactions on diffracting and converging processes are discussed and the analytic conclusion is demonstrated through the observation of numerical simulations.

关键词： converging, CCW relation, shock wave, detonation wave.

Pattern phenomena in an rf discharge dusty plasma system

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Science china(Physics,Mechanics & Astronomy) 2006年第5期49卷 588-596页

作者： HUANG Feng1,2. YE Maofu2.& WANG Long2.1. College of Science, china Agricultural university, {2. 100083, china 2. Institute of Physics, Chinese Academy of Sciences, {2. 100080, china 1. College of Science China Agricultural University Beijing 100083 China 2. Institute of Physics Chinese Academy of Sciences Beijing 100080 China

Various dust patterns are observed in an rf discharge dusty plasma system. According to the dust growth process from small to large in size, the formation of different dust patterns can be divided into two stages: the small-particle stage (or dust cloud stage), and the large-particle stage (or dust crystal stage). The evolution relations between different dust patterns with gas pressure changing are investigated. Dust voids, dust acoustic waves and strong turbulence modes are presented at the small-particle stage. The self-organized dust lattices and dust clusters are investigated at the large-particle stage. The static structure of a dust lattice is characterized by means of the pair correlation function. Dust clusters formed by particles with different numbers and the regular evolution of the clusters with gas pressure are also investigated. The packing sequences of dust clusters are verified through two-dimensional confined molecular dynamics simulations.

关键词： dusty plasma dust patterns

A 12.bit multichannel ADC for pixel detectors in particle physics and nuclear imaging

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Science china(Technological Sciences) 2010年第5期53卷 1208-1214页

作者： WEI Wei1,2.3,WANG Zheng1,3 & ZHAO JingWei1,3 1 Institute of High Energy Physics,Chinese Academy of Sciences,beijing 100049,{2. 2.graduate university of Chinese Academy of Sciences,beijing 100049,{2. 3 Key Lab of Nuclear Detection Technology and Nuclear Electronics of Chinese Academy of Sciences,beijing 100049,{2. 1. Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 China2. Graduate University of Chinese Academy of Sciences Beijing 100049 China3. Key Lab of Nuclear Detection Technology and Nuclear Electronics of Chinese Academy of Sciences Beijing 100049 China

Modern pixel detectors in nuclear and particle physics experiments and also in nuclear imaging,starve for highly integrated application specified integrated circuit(ASIC),whereas in china the study of ASIC still stays far away from practical *** lack of ASIC strictly limits the research and development of domestic high energy physics field.A 12.bit multichannel ADC designed for high density readout is introduced as a major candidate for solution.A precise model is discussed and the simulation fully agrees with the model,which indicates a key principle of *** is performed according to the given rule,and novel layout techniques are carried *** results in all aspects are also obtained,showing an excellent real performance,which satisfies the practical requirement.

关键词： application specified integrated circuit high density readout Wilkinson ADC multi-channel ADC

Observational features of pulsar glitches

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Science china(Physics,Mechanics & Astronomy) 2010年第S1期53卷 3-8页

作者： WANG Na1 & YUAN JianPing1,2.1 Urumqi Observatory, NAOC, Urumqi 830011, china 2.graduate {2. of CAS, beijing 100049, china 1. Urumqi Observatory NAOC Urumqi 830011 China2. Graduate University of CAS Beijing 100049 China

Pulsar glitches are sudden increases in the rotation rate which probably result from angular momentum transfer within the neutron star. We review the observational features of the 39 glitches detected at Nanshan from 2.00 to 2.08, including several events which appear to be slow glitches. A wide variety of post-glitch behavior is observed with very little recovery in some pulsars and over-recovery in others. Analysis of the whole sample of known glitches shows that fractional glitch amplitudes are correlated with characteristic age with a peak at about 105 years, but there is a spread of two or three orders of magnitude at all ages. For individual pulsars with many glitches, the time until the next glitch is sometimes proportional to the fractional glitch amplitude.

关键词： neutron star pulsar observation timing glitch

Urban Water Supply Industry Marketization of china in View of Public Water Service and Water Resource Management

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Chinese Journal of Population,Resources and Environment 2010年第2期8卷 55-60页

作者： Wang Yining 1,2.1.Institute of Geographic Science and Natural Resources Research,CAS,beijing 100101,china {2. School of the Chinese Academy of Sciences,beijing 100049,china Institute of Geographic Science and Natural Resources Research CAS Beijing 100101 China graduate School of the Chinese Academy of Sciences Beijing 100049 China

Started with the discussions on the value orientation of urban water supply industry marketization,the article points out that the current urban water supply industry marketization reform is inconsistent with the goal of public water service equalization to some *** article also analyzes the problems emerged in urban water supply industry marketization reform and various rea-sons in view of efficiency and *** efficiency and fairness oriented management model is built in this article to illustrate how the government should conciliate interests of various communities involved in the process of marketization reform of the urban water supply industry so as to actualize the coordination of efficiency and *** the end,an assumption on urban water price is put forward to help achieve the public water service equalization.

关键词： urban water supply industry marketization public water service water resource management

CMQV+:An authenticated key exchange protocol from CMQV

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Science china(Information Sciences) 2012年第7期55卷 1666-1674页

作者： LI Hui 1,2.& WU ChuanKun 1 1 State Key Laboratory of Information Security,Institute of Software,Chinese Academy of Sciences,beijing 100190,china {2. university of Chinese Academy of Sciences,beijing 100049,china 1. State Key Laboratory of Information Security Institute of Software Chinese Academy of Sciences Beijing 100190 China2. Graduate University of Chinese Academy of Sciences Beijing 100049 China

Ustaoglu presents a secure and efficient key exchange protocol named CMQV,based on the design rationales of HMQV and *** with the latter two protocols,on one hand,CMQV achieves high performance of HMQV,and on the other,it is proven secure in eCK model as NAXOS ***,CMQV enjoys the security proof under gap Diffie-Hellman assumption as indicated by its *** this paper,we propose a variant of CMQV,called CMQV+,which is proven secure under a weaker assumption (*** Diffie-Hellman assumption) in eCK model with random oracles while maintaining the high-performance feature of CMQV as much as possible.

关键词： key exchange eCK model trapdoor-test technique provable security CDH assumption