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Land Use of the Three Gorges Reservoir Area and the Effect on Its Landscape Pattern in the Recent 50 Years

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Wuhan university Journal of Natural Sciences 2006年第4期11卷 910-914页

作者： HUANG Zhiqin 1.2,3 , ZHOU Wancun 1. ,ZHOU Jieming 4., ZHU Mingcang 3,5 1. Institute of Mountain Hazards and Environment, Chinese Academy of Sciences , Chengdu 61.04., Sichuan, china 2. graduate university of Chinese Academy of Sciences, beijing 1.004., china 3. Sichuan Institute of Land Resource Management, Chengdu 61.04., Sichuan , china 4. Department of Resources and Environment Science, Sichuan Normal university , Chengdu 61.061. Sichuan, china 5. College of Information Engineering, Chengdu university of Technology, Chengdu 61.059, Sichuan, china Institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu Sichuan China graduate {1. of Chinese Academy of Sciences Beijing China Sichuan Institute of Land Resource Management Chengdu Sichuan China Department of Resources and Environment Science Sichuan Normal University Chengdu Sichuan China College of Information Engineering Chengdu University of Technology Chengdu Sichuan China

The paper makes detailed analysis on the changing processes of the main types of land use in Three Gorges Reservoir Area through the techniques of RS （Remote Sense） and GIS （Geography Information System）. Based on the theory of landscape ecology, many types of landscape pattern indexes are calculated and made correlation analysis. The results indicate that： in 1.95 the ecological environment of Three Gorges Reservoir Area was the most vulnerable in the recent 50 years, but resumed in 2002; the landscape pattern diversity index, fractal dimension index and fragmentation index has close correlation with the area of land use/cover change （LUCC）. The research also releases that the increase of the cultivated land, grassland and construction land deteriorates the landscape ecological pattern, while the increase of forest land area will help restore the landscape ecological pattern to its original state. The rapid change of grassland is an important index of the change of landscape pattern, because it has the most effect on change of landscape pattern index.

关键词： the Three Gorges Reservoir Area land use/cover change landscape pattern.

Pole assignment in descriptor periodic systems

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Science china Mathematics 2005年第10期48卷 1309-1332页

作者： FAN Hung-Yuan~1.LIN Wen-Wei~1.& XU Shufang~2 1. Department of Mathematics,Tsing Hua university,Hsinchu 300{1.,china 2. LMAM,School of Mathematical Sciences,Peking university,beijing 1.0871.china 1. Department of Mathematics Tsing Hua University 30043 Hsinchu China 2. LMAM School of Mathematical Sciences Peking University 100871 Beijing China

In this paper a pole assignment problem is considered for the descriptor linear discrete-time periodic systems, which is using the periodic proportional-derivative feedback to modify a given system such that the closed loop system has a specified selfconjugate set of eigenvalues. It is shown that the complete reachability of an open loop periodic system is equivalent to the possibility of assigning an arbitrary set of the eigenvalues to the system by choosing the suitable periodic proportional-derivative feedback.A computational approach is also proposed to solve the problem, which uses the reliable numerical techniques based on the orthogonal transformations. Numerical examples are presented to illustrate the effectiveness of the proposed approach.

关键词： descriptor linear periodic system, pole assignment, proportional and derivative feedback, numerical method, periodic Schur decomposition.

The influence of moderate ENSO on summer rainfall in eastern china and its comparison with strong ENSO

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Chinese Science Bulletin 2008年第5期53卷 791-800页

作者： XUE Feng1.& LIU ChangZheng1.2 1.Institute of Atmospheric Physics, Chinese Academy of Sciences, beijing 1.0029,{1. 2 graduate university of Chinese Academy of Sciences, beijing 1.004.,{1. Chinese Acad Sci Inst Atmospher Phys Beijing 100029 Peoples R China.

The 6 major ENSO events since 1.79 are classified into the strong and moderate ENSO based on in-tensity. The composite analysis is performed to reveal the influence of ENSO on East Asian summer monsoon (EASM) and summer rainfall in eastern china. It is shown that the influence is changed with the seasonal cycle in summer, with a weaker influence in June and a stronger influence in August, in-dicating a long lagged effect of ENSO on EASM. Besides, the circulation and rainfall anomalies caused by the strong ENSO are also stronger with an earlier starting time, while the influence of the moderate ENSO is evident in August. The composite summer rainfall in eastern china for the moderate ENSO exhibits a northern rainfall pattern, which is totally different from the classical ENSO-type rainfall pat-tern. Based on the composite analysis, two moderate ENSO years with a similar intensity (i.e., 1.95 and 2003) are compared. The result shows that, the response of EASM to the moderate ENSO during June and July is, to a certain degree, modulated by the circulation systems in mid-high latitudes of Eurasia and in the Southern Hemisphere, thereby inducing a different rainfall distribution in eastern china. In comparison with the strong ENSO in 1.83, it is further revealed that, the strong ENSO plays a dominant role in summer rainfall anomalies in eastern china as well as in controlling the influence of the other factors on EASM. The strong ENSO is therefore different with the moderate ENSO.

关键词：中国东部海洋气象学厄尔尼诺现象东亚季风降雨

Decoding algorithms for shortened-extended turbo product codes in WiMAX systems

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Science in china(Series F) 2009年第12期52卷 2415-2423页

作者： XU ChangLong1.3,4. YANG Wei1.2 & YE WeiChen4.1.State Key Laboratory of Networking and Switching Technology, beijing university of Posts and Telecommunications, beijing 1.004., china 2 State Key Laboratory of Rail Traffic Control and Safety, beijing Jiaotong university, beijing 1.004., china 3 National Mobile Communications Research Laboratory, Southeast university, Nanjing 21.096, china 4.Intel Corporation, beijing Kerry Center, Guanghua Road 1. beijing 1.0020, china State Key Laboratory of Networking and Switching Technology Beijing University of Posts and Telecommunications Beijing 100044 China State Key Laboratory of Rail Traffic Control and Safety Beijing Jiaotong University Beijing 100044 China National Mobile Communications Research Laboratory Southeast University Nanjing 210096 China Intel Corporation Beijing Kerry Center Guanghua Road 1 Beijing 100020 China

The component codes of turbo product codes in WiMAX systems are extended Hamming codes and single parity check codes as well as their shortened forms, In this paper, three novel iterative decoding algorithms based on Chase, MAP algorithms and their combination are proposed for shortened-extended turbo product codes. The iterative decoding algorithm based on Chase algorithm is proposed to reduce the decoding complexity without any performance loss. An efficient MAP algorithm is then proposed to decode the component codes of shortened single parity check codes and shortened-extended Hamming codes. A comprehensive performance comparison of the proposed decoding schemes is conducted for three typical classes of turbo product codes in WiMAX OFDMA systems. The suitable decoding algorithms are recommended for different classes based on the simulation results.

关键词： block code product code iterative decoding

Absolute radiometric calibration of CBERS-02 IRMSS thermal band

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Science china(Technological Sciences) 2005年第S2期48卷 72-90页

作者： ZHANG Yong1.2,3, GU Xingfa1.3,4. YU Tao1.3, ZHANG Yuxiang5, CHEN Liangfu1.3, LI Xiaoying1.2,3, LI Xiaowen1.3 & HE Liming6 1. State Key Laboratory of Remote Sensing Science, Jointly Sponsored by the Institute of Remote Sensing Applications of Chinese Academy of Sciences and {1. Normal university, {1. 1.01.1. china 2. {4. university of Chinese Academy of Sciences, beijing 1.0039, china 3. The Center for National Spaceborne Demonstration, {1. 1.01.1. china 4. Institut National de la Recherche Agronomique, Climat Sol Environnement, 84.1.0}Avignon, France 5. National Satellite Meteorological Center, {1. 1.0081. china 6. State Environmental Protection Administration, {1. 1.0029, china Chinese Acad Sci Inst Remote Sensing Applicat State Key Lab Remote Sensing Sci Beijing 100101 Peoples R China beijing Normal Univ State Key Lab Remote Sensing Sci Beijing 100101 Peoples R China Chinese Acad Sci Grad Univ Beijing 100039 Peoples R China Ctr Natl Spaceborne Demonstrat Beijing 100101 Peoples R China INRA F-84914 Avignon France Natl Satellite Meteorol Ctr Beijing 100081 Peoples R China State Environm Protect Adm Beijing 100029 Peoples R China

Based on the laboratory calibration before launch of CBERS-02 IRMSS thermal infrared channel, the onboard blackbody calibration, the radiometric cross- calibration against TERRA MODIS corresponding channel and the in-flight field calibration at Lake Qinghai: water surface radiometric calibration test site of china on Aug. 1., 200{1.are carried out in this research. When making onboard blackbody calibration of CBERS-02 IRMSS, it is necessary to understand inside structures and light path in IRMSS camera and receive and process calibration blackbody signals at normal and high temperatures. Onboard blackbody calibration results of each detector are very important to relative radiometric calibration of images processing and absolute radiometric calibration of each detector. In-flight field calibration mainly contains field experiments, obtaining synchronous images, spectrum marching and MODTRAN radiative transmi- ssion computation. Radiometric cross-calibration of CBERS-02 IRMSS thermal band against TERRA MODIS selected 6 times synchronous images of two sensors passing through Lake Qinghai and Lake Taihu from August to December, 200{1.to compute the cross calibration data. Combining the in-flight field calibration and radiometric cross calibration data, the absolute radiometric calibration coefficients are calculated by the linear regression method. This new calibration model can obviously control the radiometric calibration uncertainties aroused by the single point method used in the in-flight calibration of CBERS-02 IRMSS, this kind of sensors cannot receive the cosmic background radiation. In this research, the radiometric calibration coefficients obtained through the linear regression model are 8.53 (gain, unit: DN/W m?2sr?1.m?1. and {1..92 (offset, unit: DN).

关键词： CBERS-02 IRMSS thermal band in-flight field calibration onboard blackbody calibration cross calibration.

Statistical distribution of nonlinear random wave height

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Science china Earth Sciences 2006年第4期49卷 443-448页

作者： HOU Yijun1. GUO Peifang1.2, SONG Guiting1.2, SONG Jinbao1. YIN Baoshu1.& ZHAO Xixi1.2 1. Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071. china 2. {1. university of the Chinese Academy of Sciences, beijing 1.0039, china 1. Institute of Oceanology Chinese Academy of Sciences Qingdao 266071 China 2. graduate {1. of the Chinese Academy of Sciences Beijing 100039 China

A statistical model of random wave is developed using Stokes wave theory of water wave dynamics. A new nonlinear probability distribution function of wave height is presented. The results indicate that wave steepness not only could be a parameter of the distribution function of wave height but also could reflect the degree of wave height distribution deviation from the Rayleigh distribution. The new wave height distribution overcomes the problem of Rayleigh distribution that the prediction of big wave is overestimated and the general wave is underestimated. The prediction of small probability wave height value of new distribution is also smaller than that of Rayleigh distribution. Wave height data taken from East china Normal {1. are used to verify the new distribution. The results in- dicate that the new distribution fits the measurements much better than the Rayleigh distribution.

关键词： Random ocean wave, nonlinearity, wave height distribution.

Molecular cloning of growth hormone receptor (GHR) from common carp(Cyprinus carpio L.)and identification of its two forms of mRNA transcripts

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Progress in Natural Science:Materials International 2006年第11期16卷 1156-1163页

作者： SUN Xiaofeng~ 1.2 , GUO Qionglin~1.*, HU Wei~1. WANG Yaping~1.and ZHU Zuoyan~1.1. State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 4.0072,{1. 2. graduate School of Chinese Academy of Sciences, beijing 1.0039,{1.) [a]State key Laboratory of Freshwater Ecology and Biotechnology Institute of Hydrobiology Chinese Academy of Sciences Wuhan China China [b]graduate School of Chinese Academy of sciences Beijing China

The cDNA of growth hormone receptor (GHR) was cloned from the liver of 2-year common carp (Cyprinus carpio L.) by reverse transcription-polymerase chain reaction (RT-PCR) and rapid amplification of cDNA end (RACE). Its open reading frame (ORF) of 1.06 nucleotides is translated into a putative peptide of 602 amino acids, including an extracellular ligand-binding domain of 24. amino acids (aa), a single transmembrane domain of 24.aa and an intracellular signal-transduction domain of 334.aa. Sequence analysis indicated that common carp GHR is highly homologous to goldfish (Carassius auratus) GHR at both gene and protein levels. Using a pair of gene-specific primers, a GHR fragment was amplified from the cDNA of 2-year common carp, a 224.bp product was identified in liver and a 321.bp product in other tissues. The sequencing of the products and the partial genomic DNA indicated that the difference in product size was the result of a 97 bp intron that alternatively spliced. In addition, the 321.bp fragment could be amplified from all the tissues of 4.month common carp including liver, demonstrating the occurrence of the alternative splicing of this intron during the development of common carp. Moreover, a semi-quantitative RT-PCR was performed to analyze the expression level of GHR in tissues of 2-year common carp and 4.month common carp. The result revealed that in the tissues of gill, thymus and brain, the expression level of GHR in 2-year common carp was significantly lower than that of 4.month common carp.

关键词： growth hormone receptor (GHR) molecular cloning transcript expression analysis common carp.

Restoration of eroded stratal thickness in key periods of tectonic change in a multi-stage superimposed Tarim Basin in china

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Journal of Palaeogeography 2012年第2期1卷 149-171页

作者： Liu Hao1. Wang Yingmin2 1. School of Marine Sciences, china {1. of Geosciences (beijing), beijing 1.0083, china 2. School of Geosciences, china {1. of Petroleum (beijing), beijing 1.224., china School of Marine Sciences China University of Geosciences (Beijing) Beijing 100083 China School of Geosciences China University of Petroleum (Beijing) Beijing 102249 China

With an area of 56×1.4.m2, the Tarim Basin is the largest inland basin in{1. and is also generally acknowledged as one of the most important areas for potential oil and gas exploration. On the basis of data from 22 regional seismic profiles and 4. drilling wells, 1. important first-order and second-order regional unconformities were *** all the main unconformities are superimposed unconfomities. Since the Cambrian, 5 key periods of tectonic change have occurred during the evolution of the Tarim Basin. The total eroded stratal thickness of the above-mentioned unconformities was calculated by using the method of virtual extrapolation of seismic reflection. The results indicate that the total eroded stratal thickness of different periods is quite different in different locations of the basin. Taking the Upper-Middle Ordovician as an example, its thickness restoration of eroded strata was calculated into individual stages i.e. its thickness restoration of eroded strata was calculated to different tectonic periods. Otherwise, as for the specific period of tectonic change, the underlying strata were, respectively eroded and thus the thickness restoration of eroded strata was calculated into individual intervals. Taking the Early Hercynian period as an example, the eroded stratal thickness was calculated into individual intervals to calculate the ratio of intervals of various ages occupying the total eroded thickness. The results show that for the same stratum, its degree of erosion is quite different in different periods and at different locations, due to the varying influence of tectonic movement. The unconformities of some key periods of tectonic change have different controls on the degree of erosion and the eroded range of the individual period of the underlying strata which are the typical characteristics of multi-stage superimposition of unconformities in the Tarim Basin.

关键词： Tarim Basin extrapolation of virtual surface key period of tectonic change superimposed unconformity restoration of eroded stratal thickness

CH_4.uptake flux of Leymus chinensis steppe during rapid growth season in Inner Mongolia,{1.

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Science china Earth Sciences 2010年第7期53卷 977-983页

作者： GENG YuanBo1. LUO GuangQiang1.2 & YUAN GuoFu1.1.Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, beijing 1.01.1.{1. 2 graduate university of Chinese Academy of Sciences, beijing 1.004.,{1. 1. Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China2. Graduate University of Chinese Academy of Sciences Beijing 100049 China

The influence of near ground atmosphere CH4.concentration, soil water content, soil Eh, plants, soil temperature, and pH on CH4.uptake flux of Leymus chinensis steppe during rapid growth season was studied using field in-situ measurement in Xilin River basin of Inner Mongolia, china. The results showed that CH4.uptake flux was positively correlated with near ground atmosphere CH4.concentration and soil Eh but negatively correlated with soil water content. Precipitation may decrease the CH4.flux by increasing the soil water content. The average fluxes of three treatments during the observation period were 1.52 (natural conditions, 1.51.(aboveground plants were excluded), and 2.00 mg m?2 d?1.(all plants were removed), respectively. The difference between the CH4.flux of natural condition treatment and that of removing aboveground plants treatment is small, whereas the flux of removing all plants treatment is larger than the other two treatments. This means that the contribution of aboveground plants to CH4.uptake flux is smaller than that of roots or roots-removing process. CH4.uptake flux is not sensitive to soil temperature and the narrow-ranged soil pH (6.36–7.86). The Leymus chinensis steppe acts as a sink for CH4. and thus more studies should be focused on its affecting factors and related mechanisms.

关键词： CH4 uptake flux Leymus chinensis steppe affecting factors static opaque chamber/gas chromatography method