检索结果-南通市图书馆

Satellite infrared remote sensing observation of surface circulation of the northeast South{2. Sea in winter

在线全文

学校读者我要写书评

暂无评论

Acta Oceanologica Sinica 2000年第3期19卷 81-92,157-159页

作者：许建平 key Lab of Ocean Dynamic Processes State Oceanic Administration Second Institute of Oceanography Hangzhou 310012 China

Based on several images taken by. the NOAA -11 and - 12.advanced very high resolution radiometer (AVHRR/2. during 1989-1993, and combined with a larger-scale of oceanographic investigation during 8-2. March 1992. some related questions of the physical oceanography in the South {4. As have been discussed. The results show that there were a more complementary action for the investigation and study on the physical oceanographic phenomena in the South{4. As using the satellite imageries and in-situ data, and the distribution and variation of the satellite-derived sea surface tempera- ture field in the northeast South{4. Sea basically mirrored the results obtained from in-situ investigation. Some of the large-scale and meso-scale marine phenomena varied with the long and medium periods, for instance, an anticyclonic meandering of the Kuroshio path when it flowed through the Bashi Channel, the win water with high temperature along the west coastline of Lain Island, the western and northern warmer water tongues off the southwest of Taiwan Island,{4., as well as the thermal front along the continental shelf off Guangdong, were well presented in both the satellite imageries and in-situ data. Then, there the can be revealed some marine phenomena with a short period, or in the further large area using the satellite imageries, which will provide scientific basis for planning and carrying out the effective marine investigation. Finally, a map of surface circulation pattern in the northeast South{4. Sea in winter is sketched according to the comprehensive analysis of the satellite and in-situ data.

关键词： Satellite AVHRR sea surface temperature (SST) circulation front Kuroshio continental shelf South china Sea

福建省永安市西洋镇2.5a生人促阔叶林与伐前林分的对比评价

在线全文

学校读者我要写书评

暂无评论

山地学报 2010年第1期28卷 63-68页

作者：张晓红黄清麟张超中国林业科学研究院资源信息研究所国家林业局林业遥感与信息技术重点实验室西南林学院资源学院

福建省永安市西洋镇2.5a生人促阔叶林分平均胸径、树高、密度、单位面积蓄积量和平均年生长量分别为2.0cm、1.8m、19533株/hm2.7.0m3/hm2.2.80m3/(hm2.a),乔木层物种丰富度R、多样性指数SW、均匀度E和生态优势度ED分别为33、2.93、0.6... 详细信息

福建省永安市西洋镇2.5a生人促阔叶林分平均胸径、树高、密度、单位面积蓄积量和平均年生长量分别为2.0cm、1.8m、19533株/hm2.7.0m3/hm2.2.80m3/(hm2.a),乔木层物种丰富度R、多样性指数SW、均匀度E和生态优势度ED分别为33、2.93、0.62.0.2.,林分相对直径分布范围0.2.～3.00,直径分布为反J型,表现为异龄林特征。35a生的伐前林分平均胸径、树高、密度、单位面积蓄积量和平均年生长量分别为13.6cm、10.5m、1185株/hm2.101.3m3/hm2.2.89m3/(hm2.a),乔木层物种丰富度R、多样性指数SW、均匀度E和生态优势度ED分别为2.、3.72.0.81和0.10,林分相对直径分布范围0.4.～2.50,直径分布为反J型,表现为异龄林特征。

关键词：人促阔叶林伐前林分对比评价福建省永安市

Features and trends of the environmental change in the arid areas in Central Asia

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

science china Earth sciences 2007年第S1期 142-148页

作者： ZHOU KeFa1,2. ZHANG Qing3, CHEN Xi1 & SUN Li1 1 Xinjiang Institute of Ecology and Geography, Chinese Academy of sciences, ürümqi 830011, china 2.Graduate University of Chinese Academy of sciences, Beijing 10004., china 3 Institute of remote sensing and Geographical Information System, Peking University, Beijing 100871, china

RS-monitoring index systems of ecological environment changes at a large scale, based on empirical data and trends in environmental change in Central Asia, are developed using NOAA and MODIS data. Moreover, with the help of mathematical statistics and GIS spatial analysis, the degrees, hazards and distribution extent of various possible ecological problems are discussed, environmental changes in Central Asia in 1990 and 2.05 are separately evaluated, and dynamic changes in the environment in Central Asia over a 15-year period are analyzed. The results reveal that during the 15-year period from 1990 to 2.05, areas of degenerated vegetation in Kazakhstan, Uzbekistan, Turkmenistan, Kirghizstan and Tadzhikistan were enlarged by 0.069×105 km2. 0.081×105 km2. 0.2.6×105 km2. 0.02.×105 km2.and 0.112.105 km2. respectively. The ecological environment in Central Asia was in the state of significant degeneration and even deterioration. This study proves that NOAA and MODIS data can be used to successfully monitor the environment and provide useful results.

关键词： Central Asia ecological environment vegetation coverage GIS RS

Estimation of net primary productivity in china using remote {2. data

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Journal of Geographical sciences 2001年第1期11卷 14-23页

作者： SUN Rui, ZHU Qi-jiang (Dept. of Resources and Environment sciences, Beijing Normal University, Beijing 100875,{2.) Dept. of Resources and Environment sciences Beijing Normal University Beijing China

It is significant to estimate terrestrial net primary productivity (NPP) accurately not only for global change research, but also for natural resources management to achieve sustainable development. remote sensing data can describe spatial distribution of plant resources better. So, in this paper an NPP model based on remote sensing data and climate data is developed. And 1km resolution AVHRR NDVI data are used to estimate the spatial distribution and seasonal change of NPP in{4.. The results show that NPP estimated using remote sensing data are more close to truth. Total annual NPP in{4. is 2.64.X109 tC. The spatial distribution of NPP in{4. is mainly affected by precipitation and has the trend of decreasing from southeast to northwest.

关键词： remote sensing net primary productivity vegetation model seasonal change

Improving Global VTEC inversion with Inequality Constraint Least Square

在线全文

学校读者我要写书评

暂无评论

Improving Global VTEC inversion with Inequality Constraint L...

Facile Synthesis of Palladium Nanoparticles Encapsulated in Amine Functionalized Mesoporous Metal-organic Frameworks and Catalytic for Dehalogenation of Aryl Clorides

第三届中国卫星导航学术年会

作者： Hongping Zhang 1,2.Peiliang Xu 4.Maorong Ge 5,Wenhui Han 3 Changjiang Geng 2.1.state key {2. of Information Engineering in Surveying,Mapping and remote sensing,Wuhan University,Wuhan 4.0070,china 2.GNSS Research Center,Wuhan University,Wuhan 4.0079,china 3 School of Geodesy and Geomatics,Wuhan University,Wuhan 4.0079,china 4.Disaster Prevention Research Institute,Kyoto University,Uji,Kyoto 611‐0011,Japan 5.Helmholtz Centre Potsdam,German Research Centre for Geosciences (GFZ),Telegrafenberg,14.73 Potsdam,Germany

Currently,ground‐based GNSS stations of the International GNSS Service （IGS） are distributed unevenly around the *** of them locate on the mainland,while only a small part of them are scattered on some islands in the *** a consequence,grid vertical total electron content （VTEC） of ESA and CODE’s IONEX products appear many unreasonable zero values （in fact negative values）,especially for the years of 2.08 and 2.09 when the solar activity was rather *** improve this situation,this paper proposes an inequality‐constrained least squares method for the solution of Global Ionospheric Mapping （GIM） with spherical harmonic functions by imposing non‐negative inequality constraints in the areas where negative VTEC values may *** then apply the new method to 2.08 IGS *** results have shown that the new algorithm efficiently eliminates the unwanted behavior of negative VTEC values that can often be seen on both middle and high latitude area of south hemisphere （S90～S4.） and north hemisphere （N5°～N9°） under current IGS *** repeatability of most GPS receivers’ DCBs have been improved ***,GIM products from this paper,CODE,JPL and ESA are compared with IGS final *** is found that inequality constraint improve the consistency of our GIM with them both at RMS and mean VTEC.

关键词：

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

Facile Synthesis of Palladium Nanoparticles Encapsulated in ...

Estimation of forest volumes by integrating Landsat TM imagery and forest inventory data

中国化学会第六届全国结构化学学术会议

作者： Yuanbiao Huang,Rong Cao~* state key {2. of Structural Chemistry,Fujian Institute of Research on the Structure of Matter,Chinese Academy of science,Fuzhou 350002.P.R.china

＜正＞Metal-organic frameworks（MOFs） have been emerging as very promising functional materials for gas storage,separation,heterogeneous catalysis,sensing,and drug delivery due to their high surface area, porosity,an...

关键词：

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

science china(Technological sciences) 2006年第z1期49卷 54-62页

作者： GU Huiyan, DAI Limin, WU Gang, XU Dong, WANG Shunzhong &WANG Hui Institute of Applied Ecology, Chinese Academy of sciences, Shenyang 110016, china School of Forestry, Northeast Forestry University, Harbin 15004., china state {4. Lab of Systems Ecology, Research Center for Eco-Environmental sciences, Chinese Academy of sciences, Beijing 100085, china Graduate University of Chinese Academy of sciences, Beijing 100039, china 1. Institute of Applied Ecology Chinese Academy of Sciences Shenyang 110016 China 2. School of Forestry Northeast Forestry University Harbin 150040 China 3. state key Lab of Systems Ecology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China 4. Graduate University of Chinese Academy of sciences Beijing 100039 China

Accurate information about forest volumes is essential for forest management planning. The survey interval of the Forest Resource Inventory of china (FRIC) is too long to meet the demand for timely decision-making required for forest protection, management, and utilization. Analysis of satellite imagery provides good potential for more frequent reporting of forest parameters. In this study, we describe an application of the k-nearest neighbors (kNN) method to Landsat TM imagery for improving estimation of forest volumes. Several spectral features were tested and compared in forest volume estimations, including normalized difference vegetation index, environmental vegetation index, and the combination of the spectral features. The combined index resulted in the most accurate volume estimations. The kNN estimator and the combined index were then used in forest volume estimation. The estimation error (RMSE) of the total volume was4..2., much lower than those for Larix forest (the RMSE was 51.7%) and those for the Korean pine and broadleaved forests (the estimation errors were over 71.7% and 88.19%,respectively). This preliminary study demonstrates the potential of forest volume estimations with remote {2. data to provide useful information for forest management if only limited ground information is available.

关键词： forest inventory, landsat TM, k-nearest neighbors, spectral extraction.

Spatiotemporal variations in mid-upper tropospheric methane over china from satellite observations

在线全文

学校读者我要写书评

暂无评论

Spatiotemporal variations in mid-upper tropospheric methane ...

Object-oriented land cover classification using HJ-1 remote sensing imagery

作者： ZHANG Xing Ying~(1,2.),BAI WenGuang~1,ZHANG Peng~1 & WANG WeiHe~1 1 key laboratory of Radiometric Calibration and Validation for Environmental Satellites,National Satellite Meteorological Center,{2. Meteorological Administration,Beijing 100081,{2. 2.state key laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry,Institute of Atmospheric Physics,Chinese Academy of sciences,Beijing 10002.,{2.

Spaceborne measurements by the Atmospheric Infrared Sounder(AIRS) on the EOS/Aqua satellite provide a global view of methane (CH) distribution in the mid-upper troposphere(MUT-CH).The focus of this study is to analyze the spatiotemporal variations in MUT-CH over china from 2.03 to *** of AIRS CH products versus Fourier transform infrared profiles demonstrates that its RMS error is mostly less than 1.5%.A typical atmospheric methane profile is found that shows how concentrations decrease as height increases because of surface *** found that an important feature in the seasonal variation in CH is the two peaks that exist in summer and winter in most parts of china,which is also observed in in-situ measurements at Mt. Waliguan,Qinghai Province,{2.(36.2.79°N 100.8964.E,3810 m).Also,in the summer,only one peak existed in western and southern china since there are no more significant anthropogenic sources in winter than at any other time of the *** analysis of the deseasonahzed time-series of AIRS CH in three fixed pressure layers of AIRS from 2.03 to 2.08 indicates that CH in the Northern Hemisphere has increased abruptly since 2.07,with no significant increase occurring before *** increase in china is generally more significant than in other areas around the world,which again correlates with in-situ measurements at ***.

关键词： satellite remote sensing mid-upper tropospheric methane sptiotemporal variation

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

science china Earth sciences 2010年第S1期53卷 34-44页

作者： SUN ZhongPing1,SHEN WenMing1,WEI Bin1,LIU XiaoMan1,SU Wei2.ZHANG Chao2.& YANG JianYu2.1 Satellite Environment Center,Ministry of Environmental Protection,Beijing 100094.china 2.College of Information and Electrical Engineering,china Agricultural University,Beijing 100083,china 1. Satellite Environment Center Ministry of Environmental Protection Beijing 100094 China2. College of Information and Electrical Engineering China Agricultural University Beijing 100083 China

The object-oriented information extraction technique was used to improve classification accuracy,and addressed the problem that HJ-1 CCD remote sensing images have only four spectral bands with moderate spatial *** used two {2. techniques:the selection of optimum image segmentation scale and the development of an appropriate object-oriented information extraction *** the principle of minimizing merge cost of merging neighboring pixels/objects,we used spatial autocorrelation index Moran's I and the variance index to select the optimum segmentation *** Nearest Neighborhood(NN) classifier based on sampling and a knowledge-based fuzzy classifier were used in the object-oriented information extraction *** this classification step,feature optimization was used to improve information extraction accuracy using reduced data *** two techniques were applied to land cover information extraction for Shanghai city using a HJ-1 CCD *** indicate that the information extraction accuracy of the object-oriented method was much higher than that of the pixel-based method.

关键词： HJ-1 remote sensing imagery object-oriented optimum scale of image segmentation Nearest Neighborhood(NN) classification fuzzy classification