检索结果-南通市图书馆

The application of geographic information technology to coastal geomorphology

在线全文

学校读者我要写书评

暂无评论

Acta Oceanologica Sinica 2009年第5期28卷 49-57页

作者： GUO Wei LI Shuheng ZHU Dakui School of Human Settlements and Civil Engineering Xi＇an Jiaotong University Xi＇an 710049 China Department of Computer sciences Xi＇an Jiaotong University Xi＇an 710049 China Department of Urban and Resources sciences Northwest University Xi＇an 710032 China Faculty of Environmental sciences University of Waterloo Waterloo N2L3G1 Canada key laboratory of Coast ＆ Island Development of Ministry of Education Nanjing University Nanjing 210093 China

With the development of modern oceanic observation technologies, coastal survey data have been experiencing a substantial growth. The integration management of the data from different disciplines, different sources and different formats has become a major research field in coastal geomorphology by using Geographic Information System （GIS）. This paper puts forward a new methodology framework of GIS techniques in coastal ocean geomorphology, including data acquisition, process, analysis, and representation. It focuses on some major GIS techniques to study the land-ocean interaction mechanism, such as spatial analysis, submarine topography model and three-dimension （3D） visualization, and apply its result to coastal urban planning, harbor site selection and geomorphology environment about coral reef and islands on the continental shelf. The case studies cover the whole coastal ocean to serve the social community, economical development and diplomatic rights for decision-making all round in the coastal zone. The research shows clearly that the application of coastal multi-source geospatial platform has changed the traditional coastal geomorphology science dramatically from its research scope, fields and methods, however, as made clear in this paper, extracting accurate information from remote {2. data and GIS databases for coastal geomorphological applications is a nontrivial challenge that requires the combined knowledge and skills of information scientists and geomorphologists.

关键词： coastal geomorphology geographic information system (GIS) spatial analysis threedimensional visualization

Atmospheric frontal gravity waves observed in satellite SAR images of the Bohai Sea and Huanghai Sea

在线全文

学校读者我要写书评

暂无评论

Acta Oceanologica Sinica 2010年第5期29卷 35-43页

作者： LIU Shuming LI Ziwei YANG Xiaofeng Pichel William G YU Yang ZHENG Quanan LI Xiaofeng The First Institute of Oceanography State Oceanic Administration Qingdao 266061 China National Marine Data and Information Service Tianjin 300171 China Institute of remote sensing Applications Chinese Academy of {2. Beijing 100101 China NOAA/NESDIS Center for Satellite Applications and Research Camp Springs MD 20746-4304 USA Department of Atmospheric and Oceanic science University of Maryland Maryland 20742-2425 USA IMSG at NOAA/NESDIS NOAA E/RA3 WWBG Room 102 5200 Auth Road Camp Springs MD 20746-4304 USA.

In the satellite synthetic aperture radar（SAR） images of the Bohai Sea and Huanghai Sea,the authors observe sea surface imprints of wave-like patterns with an average wavelength of 3.8 *** SAR observations with sea surface wind fields and surface weather maps,the authors find that the occurrence of the wave-like phenomena is associated with the passing of atmospheric *** authors define the waves as atmospheric frontal gravity *** dynamical parameters of the wave packets are derived from statistics of 9 satellite SAR images obtained from 2.02.to 2.08.A two-dimensional linear physical wave model is used to analyze the generation mechanism of the *** atmospheric frontal wave induced wind variation across the frontal wave packet is compared with wind retrievals from the SAR *** CMOD-5（C-band scatterometer ocean geophysical model function） is used for SAR wind retrievals VV（transmitted vertical and received vertical） for ENVISAT and HH（transmitted horizontally and received horizontally） for RADARSAT-1.A reasonable agreement between the analytical solution and the SAR observation is *** new SAR frontal wave observation adds to the school of SAR observations of sea surface imprints of AGWs including island lee waves,coastal lee waves,and upstream Atmospheric Gravity Waves（AGW）.

关键词： Atmospheric gravity waves atmospheric front generation mechanism synthetic aperture radar

在线全文

学校读者我要写书评

暂无评论

基于形态插值的图像重建方法

计算机工程与应用 2004年第18期40卷 26-28页

作者：段汕秦前清武汉大学测绘遥感信息工程国家重点实验室中南民族大学计算机科学学院武汉430074 中南民族大学计算机科学学院

该文提出了一种基于数学形态学的形态插值方法,该方法适用于对于二值图像、灰值图像以及多光谱图像的插值重构,通过形态插值技术将输入图像变换成保持某种特征的插值图像。所提出的方法是对基于测地距离函数和形态中值方法的扩展,以提... 详细信息

该文提出了一种基于数学形态学的形态插值方法,该方法适用于对于二值图像、灰值图像以及多光谱图像的插值重构,通过形态插值技术将输入图像变换成保持某种特征的插值图像。所提出的方法是对基于测地距离函数和形态中值方法的扩展,以提高插值方法的有效性为目的。该文还从应用的角度对于分割序列图像的插值重建算法进行了研究,所获得的新算法能较好地应用于各种类型图像的插值与形变。

关键词：形态插值形态算子数学形态学

基于Internet的大范围三维地形实时渲染

在线全文

学校读者我要写书评

暂无评论

武汉大学学报（理学版） 2005年第S2期51卷 199-202页

作者：段炼朱欣焰武汉大学测绘遥感信息工程国家重点实验室湖北武汉430079

基于Internet、分布式计算以及计算机图形学概念,提出了使用J2.E实现基于Web的大范围三维地形实时渲染的实现方法,分析了基于Web的三维地形渲染系统的开发过程中三维地表模型的建立、场景漫游,地形块拼接等环节的关键技术.这一方法集成... 详细信息

基于Internet、分布式计算以及计算机图形学概念,提出了使用J2.E实现基于Web的大范围三维地形实时渲染的实现方法,分析了基于Web的三维地形渲染系统的开发过程中三维地表模型的建立、场景漫游,地形块拼接等环节的关键技术.这一方法集成了GIS、三维地形可视化、分布式计算以及网络通信等技术,允许用户通过标准Internet浏览器来应用远程功能对DEM数据进行可视化分析.

关键词：地理信息系统网络三维三维地形可视化数字高程模型

Reference point of floating-reference method for blood glucose sensing

在线全文

学校读者我要写书评

暂无评论

Chinese Optics Letters 2010年第4期8卷 421-424页

作者：杨越陈文亮史振志徐可欣 state key {2. of Precision Measuring Technology and Instrument Tianjin University

A problem in terms of the accuracy of noninvasive measurement of blood glucose with near-infrared（NIR） spectroscopy is mainly caused by the weak glucose signal and strong background *** report the existence of the radial reference point in a floating-reference method,which is supposed to solve this *** on the analysis of the infinite diffusion theory,the local condition of the reference point is deduced *** the experiments using the intralipid solutions are constructed to testify the existence of the reference *** order to further validate our results,Monte Carlo simulations are performed to calculate the diffused light distribution according to the variation of the glucose concentration in the intralipid *** the reference points existing in three-layer skin model are also listed at the wavelength of 12.0-1700 nm.

关键词： Blood Computer simulation Infrared devices Infrared spectroscopy Monte Carlo methods

Dynamic change of net primary productivity and fractional vegetation cover in the Yellow River Basin using multi-temporal AVHRR NDVI Data

在线全文

学校读者我要写书评

暂无评论

Journal of Geographical sciences 2002年第1期12卷 29-34页

作者： SUN Rui1, LIU Chang-ming2. ZHU Qi-jiang1 (1. Department of Geography, Beijing Normal University, Beijing 100875, china 2. Institute of Geographic {2.s and Natural Resources Research, CAS, Beijing 100101, china) Department of Geography Beijing Normal University 北京 100875 Institute of Geographic sciences and Natural Resources Research CAS 北京 100101

An exponential relationship between net primary productivity (NPP) and integrated NDVI has been found in this paper. Based on the relationship and using multi-temporal 8 km resolution NOAA AVHRR-NDVI data, the spatial distribution and dynamic change of NPP and fractional vegetation cover in the Yellow River Basin from 1982.to 1999 are analyzed. Finally, the effect of rainfall on NDVI is examined. Results show that mean NPP and fractional vegetation cover have an inclining trend for the whole basin, and rainfall in flood season influences vegetation cover most.

关键词： net primary productivity fractional vegetation cover rainfall remote sensing

Fractional Frequency Offset Estimation for OFDM Systems in Non-Cooperative Communication

在线全文

学校读者我要写书评

暂无评论

china Communications 2016年第9期13卷 65-71页

作者： Mingqian Liu Jian Chen Bingbing Li Junfang Li state key {2. of Integrated Service Networks Xidian University Collaborative Innovation Center of Information sensing and Understanding Xidian University

The traditional fractional frequency offset(FFO) estimation schemes for orthogonal frequency division multiplexing(OFDM) in non-cooperative communication have the problems of susceptible performance with the frequency offset values and the number of OFDM symbols,a novel fractional frequency offset blind estimation scheme based on EKF for OFDM systems is *** nonlinear function of the frequency offset is calculated by employing the *** then the frequency offset is estimated by means of the iterative algorithm of *** finally fractional frequency offset is estimated by adopting repeated the above *** results demonstrate that the proposed scheme is robust to the frequency offset values without any requirements of a prior knowledge.

关键词： parameter estimation fractional frequency offset orthogonal frequency division multiplexing extended kalman filter

Feature extraction and classification of hyperspectral remote sensing image oriented to easy mixed-classified objects

在线全文

学校读者我要写书评

暂无评论

中国有色金属学会会刊：英文版 2005年第S1期15卷 168-171页

作者： ZHANG Lian-peng~1, LIU Guo-lin~2. JIANG Tao~2.(1. Department of Territory Information and Surveying Engineering, Xuzhou Normal University, Xuzhou 2.1009, china 2. Shandong University of science and Technology, Tai’an 2.1019,{2.) Xuzhou Normal Univ Dept Terr Information & Surveying Engn Xuzhou 221009 Peoples R China Shandong Univ Sci & Technol Tai An 271019 Peoples R China

The classification of hyperspectral remote sensing data is an important problem theoretically and practically. With the increase of spectral bands, the separability of objects on remote sensing image should be improved. But the effects of traditional algorithm on feature extraction such as principal component analysis(PCA) is not so good for hyperspectral image. The {4. problem is that PCA can only represent the linear structure of data set; while the data clouds of different objects on hyperspectral image usually distribute on a nonlinear manifold. This paper established an algorithm of nonlinear feature extraction named as nonlinear principal poly lines, based on the algorithm, a classifier is constructed and the classification accuracy of hyperspectral image can be improved.

关键词： hyperspectral remote sensing feature extraction classification

A preliminary study of the variation of phytoplankton absorption coefficients in the northern South china Sea

在线全文

学校读者我要写书评

暂无评论

Acta Oceanologica Sinica 2009年第5期28卷 17-29页

作者： WU Jingyu HONG Huasheng SHANG Shaoling DAI Minhan LEE Zhongping LI Shaojing state key {2. of Marine Environmental science Xiamen University Xiamen 361005 China Department of Oceanography Xiamen University Xiamen 361005 China Naval Research Lab Code 7333 Stennis Space Center MS 39529 USA

The temporal and spatial variabilities of phytoplankton absorption coefficients （a ph （λ）） and their relationships with physical processes in the northern South china Sea were examined, based on in situ data collected from two cruise surveys during May 14.to 2., 2.01 and November 2.to 2., 2.02. Significant changes in the surface water in a ph values and B/R ratios （a ph （4.0）/a ph （675）） were observed in May, which were caused by a phytoplankton bloom on the inner shelf stimulated by a large river plume due to heavy precipitation. This is consistent with the observed one order of magnitude elevation of chlorophyll a and a shift from a pico/nano dominated phytoplankton community to one dominated by micro-algae. Enhanced vertical mixing due to strengthened northeast monsoon in November has been observed to result in higher surface a ph （675）（0.002.0.006 m-1 higher） and less pronounced subsurface maximum on the outer shelf/slope in November as compared with that in May. Measurements of a ph and B/R ratios from three transects in November revealed a highest surface a ph （675） immediately outside the mouth of the Zhujiang （Pearl） River Estuary, whereas lower a ph （675） and higher B/R ratios were featured in the outer shelf/slope waters, demonstrating the respective influence of the Zhujiang River plume and the oligotrophic water of the South china Sea. The difference in spectral shapes of phytoplankton absorption （measured by B/R ratios and bathochromic shifts） on these three transects infers that picoprocaryotes are the major component of the phytoplankton community on the outer shelf/slope rather than on the inner shelf. A regional tuning of the phytoplankton absorption spectral model （Carder et al., 1999） was attempted, demonstrating a greater spatial variation than temporal variation in the lead parameter a 0 （λ）. It was thus implicated that region-based parameterization of ocean color {2. sensing algorithms in the northern South china Sea was mandatory.

关键词： phytoplankton absorption coefficient variation picoprokaryotes parameterization South china Sea