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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 {2. of Chinese 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 {2. of Chinese Academy of Science,Beijing 100049,china school of Information Science and Engineering Graduate University of Chinese Academy of Sciences Beijing China Beijing Institute of Electronic System Engineering China Aerospace Science & Industry Corp. Beijing China State Key Laboratory of Information Security Graduate University of Chinese Academy of Science Beijing 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

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 Sciences/Institute of Mountain Hazards and Environment,Chinese Academy of Sciences,Chengdu 610041,Sichuan,china 2. graduate {2. of the Chinese Academy of Sciences,Beijing 100049,china 3. school of Environmental Science and Engineering,Southwest Jiaotong {2.,Chengdu 610041,Sichuan,china Key Laboratory of Mountain Hazards and Surface Process Chinese Academy of Sciences Chengdu China graduate university of the Chinese Academy of Sciences Beijing China Institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu China school of Environmental Science and Engineering Southwest Jiaotong University Chengdu 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

Eclogites in the interior of the Tibetan Plateau and their geodynamic implications

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Chinese Science Bulletin 2009年第15期54卷 2556-2567页

作者： ZHANG KaiJun1,2.& TANG XianChun2.3 1 Department of Earth Sciences, Nanjing university, Nanjing 2.0093, china 2.Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, china 3 graduate university of Chinese Academy of Sciences, Beijing 100049, china Department of Earth Sciences Nanjing University Nanjing China Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou China graduate university of Chinese Academy of Sciences Beijing China

Eclogites have been recently reported in the interior of the Tibetan Plateau, including in the central Qiangtang metamorphic belt, in the Basu metamorphic massif of the eastern Bangong-Nujiang suture zone, and at Songdo and Pengco in the eastern Lhasa terrane. Some typical ultrahigh-pressure (UHP) metamorphic phenomena, e.g., garnet exsolution from clinopyroxene, were documented in the Basu and Pengco eclogites. The UHP metamorphism in the interior of the Tibetan Plateau marked by these eclogites generally took place in the Early Mesozoic. Along with exhumation of these eclogites, (post-) collision-related magmatism extensively occurred around the central Qiangtang belt, the eastern Ban-gong-Nujiang suture zone, and the eastern Lhasa terrane. The occurrence of these Early Mesozoic ec-logites manifests an out-of-sequence evolution of the Tethys, and they could be a product of diachro-nous collision between the eastern Qiangtang terrane and the irregular continental margin of the united western Qiangtang-Lhasa plate, along the linked eastern Bangong-Nujiang-central Qiangtang zone. The collision-related magmatic rocks could have been originated from lithospheric thickening, melting, or detachment due to the collision. The presence of UHP metamorphic rocks in central Qiangtang and Basu implies likely continental deep-subduction, and the denudation of these two metamorphic zones could have served as the source of the Triassic turbidites in the Songpan-Garzê complex and the Ju-rassic turbidites in the western Bangong-Nujiang zone, respectively. However, studies of the eclogites in the interior of the Tibetan Plateau just began, and many principal aspects still remain to be explored, such as their distributions, typical lithologies and minerals, temperature-pressure conditions, timing of formation and exhumation, protoliths and tectonic setting, and relationship with the evolution of the Tethys and large-scale basins in Tibet.

关键词：地球动力学意义青藏高原榴辉岩

POSITIVE SOLUTIONS FOR WEAKLY COUPLED NONLINEAR ELLIPTIC SYSTEMS

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Acta Mathematica Scientia 2010年第5期30卷 1577-1592页

作者：龙静杨健夫 wuhan Institute of Physics and Mathematics Chinese Academy of Sciences graduate school Chinese Academy of Sciences Department of Mathematics Jiangxi Normal University

In this article, we consider the existence of positive solutions for weakly coupled nonlinear elliptic systems {-△u＋u=（1＋a（x））｜u｜P-1u＋μ｜u｜a-2.｜v｜β＋λv in Rn,-△u＋u=（1＋b（x））｜v｜p-1v＋μ｜u｜a｜v｜β-2.＋λu in Rn To find nontrivial solutions, we first investigate autonomous systems. In this case, results of bifurcation from semi-trivial solutions are obtained by the implicit function theorem. Next, the existence of positive solutions of problem （0.1） is obtained by variational methods.

关键词： Elliptic system in RN positive solution bifurcation variational method

A mixed method for measuring low-frequency acoustic properties of macromolecular materials

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Science china(Physics,Mechanics & Astronomy) 2006年第6期49卷 729-739页

作者： LIU Hongwei1,YAO Lei1,3,ZHAO Hong1,3,ZHANG Jichuan2.3 & XUE Zhaohong2.1. National Key Laboratory of Acoustics,Institute of Acoustics,Chinese Academy of Sciences,Beijing 100080,china 2. Institute of Chemistry,Chinese Academy of Sciences,Beijing 100080,china 3. {2. university of Chinese Academy of Sciences,Beijing 100049,china National Key Laboratory of Acoustics Institute of Acoustics Chinese Academy of Sciences Beijing China graduate university of Chinese Academy of Sciences Beijing China Institute of Chemistry Chinese Academy of Sciences Beijing China

A mixed method for measuring low-frequency acoustic properties of macro-molecular materials is presented. The dynamic mechanical parameters of materials are first measured by using Dynamic Mechanical Thermal Apparatus(DMTA) at low frequen-cies,usually less than 100 Hz; then based on the Principles of Time-Temperature Super-position (TTS),these parameters are extended to the frequency range that acousticians are concerned about,usually from hundreds to thousands of hertz; finally the extended dynamic mechanical parameters are transformed into acoustic parameters with the help of acoustic measurement and inverse analysis. To test the feasibility and accuracy,we measure a kind of rubber sample in DMTA and acquire the basic acoustic parameters of the sample by using this method. While applying the basic parameters to calculating characteristics of the sample in acoustic pipe,a reasonable agreement of sound absorp-tion coefficients is obtained between the calculations and measurements in the acoustic pipe.

关键词： low-frequency acoustic properties,dynamic mechanical properties,Principles of Time-Temperature Superposition,acoustic pipe,sound absorption coefficient.

A novel method to analyze damping effect of VSC based FACTS

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Science china(Technological Sciences) 2008年第12期51卷 2112-2119页

作者： DU WenJuan1,WANG HaiFeng2.& CHENG ShiJie3 1 Southeast university,Nanjing 2.0096,china 2.Queen’s university of Belfast,Belfast,BT9 5AH,UK 3 Huazhong university of Science and Technology,wuhan 4.0074.china Southeast university Nanjing China Queen’s university of Belfast Belfast UK Huazhong university of Science and Technology Wuhan China

A novel method to analyze the damping effect of the VSC based FACTS(VBF) device is proposed,which is developed on the basis of the well-known equalarea criterion and small-disturbance analysis of power system *** use of the proposed method,two conclusions are obtained for study of the damping effect of the *** research results clearly show the contribution of the VBF control to the damping of power system *** results of an example power system are used to verify the effectiveness of the proposed method.

关键词： power system low frequency oscillations FACTS equal-area criterion

Properties of the 3/2.-[52.] band in the odd-N rare-earth nuclei

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Science china(Physics,Mechanics & Astronomy) 2011年第S1期54卷 37-43页

作者： CHEN Liang1,2. ZHOU XiaoHong1,2. ZHANG YuHu1, ZHANG ShuangQuan3 & ZHU LiHua4 1Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000, china 2.1} {2. of Chinese Academy of Sciences, Beijing 100049, china 3State Key Laboratory of Nuclear Physics and Technology, school of Physics, Peking {2., Beijing 100871, china 4china Institute of Atomic Energy, Beijing 102.13, china Institute of Modern Physics Chinese Academy of Sciences Lanzhou China graduate university of Chinese Academy of Sciences Beijing China State Key Laboratory of Nuclear Physics and Technology School of Physics Peking University Beijing China china Institute of Atomic Energy Beijing China

High-spin states in 161Er have been studied experimentally via the 150Nd(16O, 5n) reaction at a beam energy of 86 MeV. Three rotational bands built on the 5/2.[642., 3/2.[52.], and 11/2.[505] configurations have been extended up to high-spin states, and particularly, the α = -1/2.branch of the ground state 3/2.[52.] band has been revised significantly. It is found that signature inversion occurs in the 3/2.[52.] band after the band crossing in 161Er. The systematics of the signature inversion associated with the 3/2.[52.] configuration in the rare-earth region is discussed. The band properties are analyzed within the framework of a triaxial particle-rotor model, and a triaxial deformation is proposed to the 3/2.[52.] band.

关键词： high-spin states signature inversion triaxial particle-rotor model

Regional soil moisture simulation for Shaanxi Province using SWAT model validation and trend analysis

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Science china Earth Sciences 2010年第4期53卷 575-590页

作者： LI MingXing1,2.MA ZhuGuo1 & DU JiWen3 1 Key Laboratory of Regional Climate-Environment Research for Temperate East Asia,Institute of Atmospheric Physics,Chinese Academy of Sciences,Beijing 10002.,china 2.graduate {2. of Chinese Academy of Sciences,Beijing 100049,china 3 Shaanxi Administration of Meteorology,Xi’an 710014,china Key Laboratory of Regional Climate-Environment Research for Temperate East Asia Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China graduate university of Chinese Academy of Sciences Beijing China Shaanxi Administration of Meteorology Xi’an China

The soil moisture in Shaanxi Province,a region with complex topography,is simulated using the distributed hydrological model Soil Water Assessment Tool(SWAT).Comparison and contrast of modeled and observed soil moisture show that the SWAT model can reasonably simulate the long-term trend in soil moisture and the spatiotemporal variability of soil moisture in the *** to NCEP/NCAR and ERA40 reanalysis of soil moisture show that the trend of variability in soil moisture simulated by SWAT is more consistent with the *** model results suggested that high soil moisture in surface soil layers appears in the southern Shaanxi with high vegetation cover,and the Qinling mountainous region with frequent orographic *** deeper soil layers,high soil moisture appears in the river basins and *** regional soil moisture showed a generally decreasing trend on all soil layers from 1951 to 2.04,with a stronger and significant decreasing trend in deeper soil layers,especially in the northern parts of the province.

关键词： SWAT soil moisture content simulation validation trend analysis

An efficient chiral synthesis of (R)-N-[3-acetyl-4-(2.hydroxy-3-isopropylamino-propoxy)phenyl]-butanamide with high enantioselectivity

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Science china Chemistry 2009年第8期52卷 1216-1219页

作者： WANG NaiXing1,2.& TANG XinLiang1,3 1 Technical Institute of Physics and Chemistry,Chinese Academy of Sciences,Beijing 100080,china 2.College of Chemistry and Chemical Engineering,graduate {2. of Chinese Academy of Sciences,Beijing 100049,china 3 school of Chemical Engineering and Environment,Beijing Institute of Technology,Beijing 100081,china Technical Institute of Physics and Chemistry Chinese Academy of Sciences Beijing China College of Chemistry and Chemical Engineering Graduate University of Chinese Academy of Sciences Beijing China school of Chemical Engineering and Environment Beijing Institute of Technology Beijing China

R-Enantiomer of the β-receptor antagonist N-[3-acetyl-4-(2.hydroxy-3-isopropylamino-propoxy)phenyl] butanamide with high enantioselectivity was synthesized from cheap starting materials and enantiopure chiral reagent through an efficient,convenient and practical synthetic *** product was detected by 1H NMR,13C NMR,and MS,and the enatiomeric excess was determined by chiral HPLC analysis using a chiracel AD-H column.

关键词： chiral synthesis enantioselectivity enatiomeric excess chiral HPLC analysis