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Some properties on multivariate filter banks with a matrix factorization

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Progress in natural Science:Materials International 2005年第2期15卷 20-30页

作者： LIAN Qiaofang1, XIAO Hongying2. and CHEN Qiuhui3.1. Department of Mathematics, Beijing Jiaotong University, Beijing 100044, china 2. {2. of Mathematics, academy of Mathematics and System {3., chinese academy of sciences, Beijing 100080, china 3. Department of Scientific Computing and Computer Applications, Zhongshan University, Guangzhou 5102.5, china) Dept. of Mathematics Beijing Jiaotong Univ. Beijing 100044 China Inst. of Mathematics Acad. of Math. and System Sci. Chinese Acad. of Sciences Beijing 100080 China Dept. of Scientific Computing Zhongshan Univ. Guangzhou 510275 China

A class of multivariate filter banks with a matrix factorization has been developed by Chen et al. The main purpose of this paper is to discuss some further properties of this kind of filter bank, such as the completeness, accuracy of the corresponding scaling functions and the relationships with Daubechies' wavelets and the multi-wavelets provided by Chui and Lian. Moreover, some examples are given to show that this kind of filter bank has a higher accuracy for the scaling functions.

关键词： filter banks completeness accuracy matrix factorization

Validating global hydrological models by ground and space gravimetry

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chinese Science Bulletin 2009年第9期54卷 1534-1542页

作者： ZHOU JiangCun1,2.3. SUN HePing1,2.& XU JianQiao1,2.1 institute of Geodesy and Geophysics,{2., Wuhan 43.077, china 2.Key Laboratory of dynamic geodesy,{2., Wuhan 43.077, china 3.Graduate University of{2., Beijing 100049, china institute of Geodesy and Geophysics Chinese Academy of Sciences Wuhan China Key Laboratory of dynamic geodesy Chinese Academy of Sciences Wuhan China Graduate University of chinese academy of sciences Beijing China

The long-term continuous gravity observations obtained by the superconducting gravimeters (SG) at seven globally-distributed stations are comprehensively analyzed. After removing the signals related to the Earth's tides and variations in the Earth's rotation, the gravity residuals are used to describe the seasonal fluctuations in gravity field. Meanwhile, the gravity changes due to the air pressure loading are theoretically modeled from the measurements of the local air pressure, and those due to land water and nontidal ocean loading are also calculated according to the corresponding numerical models. The numerical results show that the gravity changes due to both the air pressure and land water loading are as large as 100×10-9 m s-2.in magnitude, and about 10×10-9 m s-2.for those due to the nontidal ocean loading in the coastal area. On the other hand, the monthly-averaged gravity variations over the area surrounding the stations are derived from the spherical harmonic coefficients of the GRACE-recovered gravity fields, by using Gaussian smoothing technique in which the radius is set to be 600 km. Com-pared the land water induced gravity variations, the SG observations after removal of tides, polar mo-tion effects, air pressure and nontidal ocean loading effects and the GRACE-derived gravity variations with each other, it is inferred that both the ground- and space-based gravity observations can effec-tively detect the seasonal gravity variations with a magnitude of 100×10-9 m s-2.induced by the land water loading. This implies that high precision gravimetry is an effective technique to validate the re-liabilities of the hydrological models.

关键词：重力测量水文模型模型验证和空间地面重力变化季节性波动空气压力

Sea-salt aerosol transport patterns over the Northern Hemisphere inferred from two subarctic ice core records

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Science china Earth sciences 2005年第4期48卷 576-584页

作者： YAN Yuping1,2. KANG Shichang2.3.5, SUN Junying4,5, Paul A. Mayewski2.& QIN Dahe5 1. National Climate Center, china Meteorological Administration, Beijing 100081, china 2. Climate Change institute, University of Maine, Orono, ME 04469, USA 3. institute of Tibetan Plateau research, chinese academy of sciences, Beijing 100085, china 4. chinese academy of Meteorological sciences, Beijing 100081, china 5. Key Laboratory of Ice Core and Cold Regions Environment, Cold and Arid Environmental and Engineering research institute, chinese academy of sciences, Lanzhou 73.000, china National Climate Center China Meteorological Administration Beijing China Climate Change institute University of Maine Orono ME USA institute of Tibetan Plateau research Chinese Academy of Sciences Beijing China Key Laboratory of Ice Core and Cold Regions Environment Cold and Arid Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou China chinese academy of Meteorological {2. Beijing China

Atmospheric circulation reconstruction based on glaciochemical records requires knowledge of chemical concentration controls, such as source, transport pathway and strength. To gain insight into these processes, the relationships between glaciochemical records from two Northern Hemisphere sites (Mt. Logan in Yukon Territory and 2.D in southern Greenland) and instrumental sea level pressure (SLP) series are investigated. Calibrations between Mt. Logan sea-salt sodium (ssNa+) concentration and SLP series show that ssNa+ concentrations are closely correlated with the autumntime (SON) Aleutian Low and the summertime (JJA) North Pacific Subtropical High. Both the deepened Aleutian Low and enhanced North Pacific Sub- tropical High strengthen the transport of sea-salt aerosols from the North Pacific to the Mt. Logan region. Calibrations between 2.D ssNa+ concentrations and SLP series indicate that ssNa+ concentrations are closely related to the wintertime (Jan.) Icelandic Low. A deepening of the Icelandic Low strengthens winter storms and frequent cyclogenesis over the North Atlantic and pushes more sea-salt laden air masses to the Greenland ice sheet. Therefore, ice core ssNa+ records from the Mt. Logan region can be considered as a proxy for reconstructing the au- tumntime Aleutian Low and summertime North Pacific Subtropical High, and the ssNa+ records from Greenland ice core (2.D) may provide a proxy for reconstructing the wintertime Icelandic Low.

关键词： sea-salt aerosol, ice core records, sea level pressure, subarctic regions.

Current situation and trend of arable land change in china

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Journal of geographical sciences 2000年第3期10卷 28-34页

作者： Received date: 1999-11-02.MENG Xiang-jing1 , JIA Shao-feng 2.(1.institute of Population research, People’s University of{2., Beijing 100872.{2. 2. institute of Geographic sciences and natural resources research, chinese academy of sciences, Beiji 中国人民大学北京中科院地理科学与资源所北京

How to protect arable land in the process of economic development and urbanization is a critical issue in china. In this paper, an attempt is made to analyze the situation of arable land change in china and it's relationship with population growth, economic development and urbanization. In depth analysis is also made in different regions. Forecasting is conducted to show the trend of arable land change in china based on the results of correlation analysis. Some suggestions are put forward for the policy making of reasonable utilization and protection of arable land in the future.

关键词： arable land change population growth economic development urbanization

Modeling the climate effects of different subregional uplifts within the Himalaya-Tibetan Plateau on Asian summer monsoon evolution

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chinese Science Bulletin 2012年第35期57卷 4617-4626页

作者： ZHANG Ran 1,JIANG DaBang 1,2,3.LIU XiaoDong 4 & TIAN ZhiPing 2,5 1 Climate Change research Center,chinese academy of {3.,Beijing 100029,china 2 Nansen-Zhu International research Centre,institute of Atmospheric Physics,chinese academy of {3.,Beijing 100029,china 3.Key Laboratory of Regional Climate-Environment research for Temperate East Asia,chinese academy of {3.,Beijing 100029,china 4 State Key Laboratory of Loess and Quaternary Geology,institute of Earth Environment,chinese academy of {3.,Xi’an 710075,china 5 Graduate University of chinese academy of sciences,Beijing 100049,china Climate Change research Center Chinese Academy of Sciences Beijing China Nansen-Zhu International research Centre Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China Key Laboratory of Regional Climate-Environment research for Temperate East Asia Chinese Academy of Sciences Beijing China State Key Laboratory of Loess and Quaternary Geology Institute of Earth Environment Chinese Academy of Sciences Xi’an China Graduate University of chinese academy of sciences Beijing China

Considering the different uplifting time of different subregions of the Himalaya-Tibetan Plateau(TP),a series of numerical simulations have been conducted with the Community Atmosphere Model(CAM4) developed at the National Center for Atmospheric research to explore the effects of the phased tectonic uplift of the Himalaya-TP on the evolution of Asian summer *** results show that the uplifts of the Himalaya and northern TP significantly affect the evolutions of South Asian summer monsoon and northern East Asian summer monsoon *** is,the tectonic uplift of the Himalaya intensifies the South Asian summer monsoon circulation and increases the precipitation in South Asia,whereas the uplift of the northern TP intensifies the northern East Asian summer monsoon circulation and increases the precipitation in northern East *** with previous simulations,current comparative analyses of modeling results for different subregional uplifts within the Himalaya-TP help deepen our understanding of the evolutionary history of Asian monsoons.

关键词：青藏高原隆升喜马拉雅亚洲季风高原气候夏季季风次区域隆起演化建模

Sedimentary environment of the Dajin conglomerate in Tibet, age of foraminiferan assemblages and their tectonic significance

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Progress in natural Science:Materials International 2005年第11期15卷 1014-1020页

作者： YAN Zhen, FANG Aimin, PAN Yusheng, LI Jiliang, LIU Xiaohan, YU Liangjun and ZHANG Binggao (Laboratory of Lithosphere Tectonic Evolution, institute of Geology and Geophysics, chinese academy of sciences, Beijing 10002.,{2. institute of Tibet Plateau research, chinese academy of sciences, Beijing 10002.,{2. Nanjing institute of Paleontology, chinese academy of sciences, Nanjing 2.0008,{2.) Laboratory of Lithosphere Tectonic Evolution Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China institute of Tibet Plateau research Chinese Academy of Sciences Beijing 100029 China Nanjing institute of Paleontology Chinese Academy of Sciences Nanjing 210008 China

The Dajin conglomerate, which is one of the most important sedimentary successions of the Xigaze forearc basin in Tibet, china, consists of deep-shallow marine tuffaceous turbidites and clastic rocks bearing Nummulites, Assilina, Alveolina and Lock-hartia . These fossils are very similar to the foraminiferan in the Jialazi and Maila conglomerates, and those in Gangba and Dingri areas. They developed in the Eocene. By analyzing the spatial variation of Eocene sedimentary environments of Tibet Plateau and the foraminiferan in the Dajin conglomerate, we found that Eocene sedimentation should take place on both sides of the Yarlung Tsangpo suture, and the late Eocene tectonic uplifting should make the forearc basin expose out of the sea level and begin to receive nonmarine deposits.

关键词： Dajin conglomerate marine deposits Eocene foraminiferan Yarlang Tsangpo sutnre.

Response of remotely sensed Normalized Difference Water Deviation Index to the 2.06 Drought of eastern Sichuan Basin

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Science china Earth sciences 2008年第5期51卷 748-758页

作者： ZHANG WenJiang1, LU QiFeng2. GAO ZhiQiang3.& PENG Jian4 1 School of Water Resource and Hydropower, Sichuan University, Chengdu 610065, china 2.National Satellite Meteorological Center, china Meteorological Administration, Beijing 100081, china 3.{3. of Geographic sciences and natural resources research, chinese academy of sciences, Beijing 100101, china 4 School of Environmental sciences, Peking University, Beijing 100871, china School of Water Resource and Hydropower Sichuan University Chengdu China National Statellite Meteorological Center China Meteorological Administration Beijing China institute of Geographic sciences and {2. {3. research Chinese Academy of Sciences Beijing China School of Environmental sciences Peking University Beijing China

One of the most serious droughts in last century occurred in eastern Sichuan Basin in the summer of 2.06 (hereinafter called the Drought). The response of Moderate Resolution Imaging Spectroradiometer (MODIS, boarding on NASA satellites of Terra and Aqua) to the Drought was analyzed in order to reach one practicable monitoring solution for regional soil moisture. Temporal process and spatial extension of the Drought were firstly estimated with ground meteorological and hydrological observations. Then, for the whole region of Sichuan and Chongqing, the remotely sensed Normalized Difference Water In- dex (NDWI) for the summers of 2.01―2.06 were calculated based on 8-day composite MODIS products, which were further used to construct a new water index (Normalized Difference Water Deviation Index, NDWDI) to examine the sensitivity of remote sensing in the Drought. The study showed that the NDWDI is more sensitive to regional drought than other absolute-soil-moisture-based indices. With the new index, the study extracted the spatial-temporal characteristics of the 2.06 Drought, and explored its developing and withdrawing processes, which agreed with related statistics. Compared with ground method of drought observation, the NDWDI-based remote sensing solution of this paper is more pref- erable and practicable in that the local soil properties of water consumption and supply are implicitly taken into account, and the spatial representativity limit of ground observation is circumvented to a degree as satellite remotely senses the earth surface in a way of two-dimensional pixel matrix. So, the NDWDI-based method can be used to monitor regional soil water stress situation more practically and efficiently.

关键词： Sichuan Basin drought Normalized Difference Water Deviation Index response of remote sensing regional scale

SYNTHESIS AND CHARACTERIZATION OF NEW STABILIZERS WITH OPTIMAL MOLECULAR WEIGHT

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chinese Journal of Polymer Science 2001年第4期19卷 341-350页

作者： Jiang-qing Pan institute of Chemistry chinese academy of sciences, Beijing 100080{2. 中科院化学所北京

Over 2.x 10(8) tons of polymers are produced every year, and a large portion of polymers faces the degradation problem. There are many effective methods to protect polymers against degradation and the addition of stabilizers to polymer remains the most convenient and effective way of enhancing polymer life and performance. In this article, a series of effective stabilizers with optimal molecular weight (MW), including common, monomeric and polymeric stabilizers (antioxidant and light stabilizer) were synthesized using isocyanation, controlled isocyanation, hydrosilylation, epoxide addition, macroreaction of stabilizing functional compounds and polymerization of monomeric stabilizers. The structure and performance of these new stabilizers were characterized by using IR, NMR, MS, UV-spectra, XPS and elemental analysis. The current development of stabilizer synthesis was also reviewed.

关键词： preparation of stabilizer antioxidant hindered amine light stabilizer isocyanation hydrosilylation

Preliminary results of the study on wind erosion in the Qinghai-Tibetan Plateau using 13.Cs technique

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chinese Science Bulletin 2000年第11期45卷 1019-1025页

作者： YAN Ping, DONG Guangrong, ZHANG Xinbao & ZHANG Yiyun1. Key Laboratory of Environmental Change and natural Disaster, the Ministry of Education of china, Beijing Normal University, Beijing 100875, china 2. {3. of Desert research, chinese academy of sciences, Lanzhou 73.000, china 3. {3. of Mountain Hazards and Environment, chinese academy of sciences, Chengdu 610041, china 4. Department of Physics, Sichuan Union University, Chengdu 610041, china Key Laboratory of Environmental Change and natural Disaster the Ministry of Education of China Beijing Normal University Beijing China institute of Desert research Chinese Academy of Sciences Lanzhou China institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu China Department of Physics Sichuan Union University Chengdu China

The worldwide fallout of caesium-13. (13.Cs) associated with the nuclear weapon tests during the 1950s and 1960s has provided a valuable man-made tracer for studies of soil erosion and sediment delivery. But relatively few {2.ers have used it to estimate wind erosion. In this note, the 13.Cs technique is introduced into the studies of wind erosion and its modern processes inthe Qinghai-Tibetan Plateau. Two 13.Cs reference inventories of 982.11 and 2.3.6.04 Bq · m-2.wereestablished preminarily, distributed in the south and middle-north parts of the studied arearespectively. By analyzing the patterns of 13.Cs depth profiles from sampling sites, the aeolianprocesses of erosion and deposition in nearly 40 years have been revealed, i.e. the shrub coppicedunes (S1) and semi-fixed dunefields (S3. experienced the alternation of erosion and deposition,while the grasslands (S4, S6 and S7) and dry farmlands (S5) suffered erosion only. By using 13.Csmodel, the average wind erosion rates for shrub coppice

关键词： 13.Cs technique Qinghai-Tibetan Plateau wind erosion.