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基于数字摄影测量技术的三维建模

同济大学学报（自然科学版） 2005年第1期33卷 37-41页

作者：程效军朱鲤刘俊领同济大学测量与国土信息工程系天津市大港区规划和国土资源局天津300270

以数字航空遥感立体像对为基础 ,辅以地面数字近景摄影测量的方法 ,建立城市三维景观模型 .根据遥感像对之间的相互关系建立一个交会模型 ,得到地物点坐标 ,建立数字表面模型 (DSM) ,然后通过纹理映射描述细部 .实践证明 ,这一方法具有... 详细信息

以数字航空遥感立体像对为基础 ,辅以地面数字近景摄影测量的方法 ,建立城市三维景观模型 .根据遥感像对之间的相互关系建立一个交会模型 ,得到地物点坐标 ,建立数字表面模型 (DSM) ,然后通过纹理映射描述细部 .实践证明 ,这一方法具有精度高和速度快等特点 ,能有效地实现速度和逼真度的兼顾 ,特别是对于大范围区域的三维建模更能显示其优越性 .

关键词：数字摄影测量三维建模纹理映射影像匹配

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有限混合纹理模式及其纹理分割框架

计算机工程与应用 2009年第30期45卷 188-193页

作者：谢兴谢玉波秦前清武汉大学测绘遥感信息工程国家重点实验室武汉430079

受到基于模型和基于结构的纹理分析方法的启发,提出一种新的特征提取方法—有限混合纹理模式。纹理特征采用聚类的方法进行计算,避免了基于模型方法复杂的参数求取过程,同时也突破了基于结构的方法纹理表达能力不足的问题。在该特征的... 详细信息

受到基于模型和基于结构的纹理分析方法的启发,提出一种新的特征提取方法—有限混合纹理模式。纹理特征采用聚类的方法进行计算,避免了基于模型方法复杂的参数求取过程,同时也突破了基于结构的方法纹理表达能力不足的问题。在该特征的基础上,给出相应的纹理分割框架,并通过定量和定性实验验证了所提算法的有效性。

关键词：有限混合纹理模式局部变化模式纹理分割

TWO-DIMENSION PERIODIC CARDINALINTERPOLATORY WAVELETS

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Analysis in Theory and Applications 1999年第1期15卷 64-74页

作者： Zhu Changqing(Zhengzhou Institute of surveying and mapping, china)(Zhejiang university, china) Zhengzhou Institute of surveying and mapping Zhengzhou China state key Lab. CAD & CG Zhejiang University Hangzhou China

In this paper, we construct two-dimension periodic interpolatory scaling function and wavelets from a periodic function g(x1, x2), whose Fourier coefficients are positive, and obtain some properties of scaling functio... 详细信息

关键词： oscillatory integral operator multiplier singularity

基于Internet的大规模城市建筑三维场景可视化研究

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系统仿真学报 2009年第10期21卷 2965-2970,2976页

作者：何正伟吴华意陈静武汉大学测绘遥感信息工程国家重点实验室武汉430072

城市场景的构建是数字城市的基础。在互联网上实现大规模城市建筑物场景实时绘制,受到带宽瓶颈及三维可视化海量数据吞吐量的限制。通过分析其特点后,设计了适合网络传输的三维模型数据结构和充分考虑可视化效率的系统服务架构,提出了... 详细信息

城市场景的构建是数字城市的基础。在互联网上实现大规模城市建筑物场景实时绘制,受到带宽瓶颈及三维可视化海量数据吞吐量的限制。通过分析其特点后,设计了适合网络传输的三维模型数据结构和充分考虑可视化效率的系统服务架构,提出了完全层次四叉树与集合的混合结构的数据组织模型,分析和论证了构建模型依据和方法。然后,讨论了建筑物场景的调度策略和方案。开发了虚拟地球平台GeoGlobe并运用于两个应用系统。实验和应用结果表明,能在普通PC机上实现大规模建筑物场景的流畅调度、实时浏览,可视化效果和用户体验好。

关键词：网络GIS 城市建筑物模型海量数据数据组织模型实时三维浏览

Performance Analysis of BeiDou Satellite Navigation System （4IGSO+3GEO） in Standard Positioning and Navigation

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Performance Analysis of BeiDou Satellite Navigation System ...

第三届中国卫星导航学术年会

作者： Gao zhouzheng1,3,Zhang Hongping1,2,Hu Zhigang1,Pengjunhuan3 1.GNSS Research Center,wuhan university,wuhan 430079 2.state key laboratory of Information Engineering in surveying,mapping and Remote Sensing,wuhan university,wuhan 430079 3.Land Science Department china university of Geosciences,Beijing 100083

Currently,BeiDou satellite navigation system can be used for real-time positioning and navigation with 4IGSO+3GEO satellites in the *** paper first briefly introduces some new progresses of BeiDou *** the distribution of BeiDou’s DOP value over the Pacific-Asia area is given according to current BeiDou Satellite’s *** evaluate and find bad satellite’s performance in running,we provide a simple way to detect BeiDou satellite’s abnormality by using continuous static observation *** processing 15 days’data obtained from several static stations and some dynamic observations collected in the field,we evaluate the accuracy of current BeiDou System’s positioning and *** results show that the horizon positioning accuracy is better than 20 meters while the vertical accuracy is better than 30 meter,the velocity accuracy is better than 0.4 meter/second.

关键词： BeiDou Satellite Navigation System Single Point Positioning GPS Precise Point Positioning Navigation Accuracy

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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

Concentration and distribution of 17 organochlorine pesticides (OCPs) in seawater from the Japan Sea northward to the Arctic Ocean

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Science china Chemistry 2010年第5期53卷 1033-1047页

作者： CAI MingGang 1,2,QIU CanRong 1,SHEN Yuan 1,CAI MingHong 3,HUANG ShuiYing 1,QIAN BiHua 1,SUN JiongHui 1 & LIU XiaoYan 1 1Department of Oceanography,College of Oceanography and Environmental Science,Xiamen university,Xiamen 361005,china 2state key laboratory of Marine Environmental Science,Xiamen university,Xiamen 361005,china 3state Oceanic Administration key laboratory for polar Science,polar Research Institute of china,Shanghai 200136,china Department of Oceanography College of Oceanography and Environmental Science Xiamen University Xiamen China state key laboratory of Marine Environmental Science Xiamen University Xiamen China state Oceanic Administration key laboratory for polar Science Polar Research Institute of China Shanghai China

Seventeen classic organochlorine pesticides in surface seawater were studied in terms of their composition pattern as well as their distribution pattern in the areas covering the Japan Sea,Okhotsk Sea,Bering Sea,Chukchi Sea and Arctic *** concentrations varied,but roughly two levels were seen with one ranging between 0.1 and 1 ng L-1 for most HCH isomers and the other lower than 0.1 ng L-1 for other *** the 17 target compounds,HCHs were dominant with a total concentration percentage generally more than 50%,and a relatively high concentration percentage of heptachlor and aldrine was also observed at scattered *** historical long-term trend of several target chemicals in the five sea zones considered was discussed in comparison with previous ***-sea zone comparison was carried out for individual chemicals by comparing the concentration variation in all five sea zones.A higher variation in concentration was generally found in the northern sea zones,namely the Bering Sea,Chukchi Sea and Arctic Ocean,for most target *** sum concentration of the 17 target chemicals displayed a general trend of increasing northward from the Japan Sea to the Okhotsk Sea to the Bering Sea to the Arctic *** latitudinal trends were found forγ-HCH andγ-HCH,and the reason of this difference was discussed by considering their divergence of thermodynamic properties,which could contribute to a slightly different fractionation effect during their northward transport driven by atmospheric long range *** source of the HCHs was identified by analyzing theγ-HCH/γ-HCH ratio,which was less than 4 without exception,indicating a component characteristic featuring a mixture of technical HCHs and *** addition,the vertical distribution ofγ-HCH,γ-HCH and their ratio at station B80 was *** patterns were found in the upper 300 m while in layers from 300 m downward to 3500 m the patterns were fairly *** vertical p

关键词： organochlorine pesticides Arctic Ocean solid-phase extraction solid-phase microextraction

Radiosonde observations of high-latitude planetary waves in the lower atmosphere

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Science china Earth Sciences 2010年第6期53卷 919-932页

作者： WANG Rui1,2,3, ZHANG ShaoDong1,2,3 & YI Fan1,2,3 1 School of Electronic Information, wuhan university, wuhan 430079, china 2 key laboratory of Geospace Environment and Geodesy, Ministry of Education, wuhan 430079, china 3 state Observatory for Atmospheric Remote Sensing, wuhan 430079, china School of Electronic Information Wuhan University Wuhan China key laboratory of Geospace Environment and Geodesy Ministry of Education Wuhan China state Observatory for Atmospheric Remote Sensing Wuhan China

The characteristics of high-latitude planetary waves (PWs) in the troposphere and lower stratosphere (TLS) are studied by using the data from radiosonde observations during 1998 to 2006 at three Alaskan stations in USA (Nome, 64.50°N, 165.43°W; McGrath, 62.97°N, 155.62°W; Fairbanks, 64.82°N, 147.87°W). It is found that strong PWs exist in two regions. One is around tropopause, and the other is in the polar night jet (PNJ) in winter. The PW activities are rather intermittent, and their lifetimes are no longer than two months. Among three perturbation components in zonal and meridional winds and temperature, the temperature disturbance amplitude is the smallest, and the amplitude for the meridional wind component the largest. Around the tropopause, quasi 5-, 10-, and 16-day PW activities can be observed simultaneously. Among these PW components, the quasi 5-day and 10-day PW are the weakest and strongest, respectively. Moreover, PWs around the tropopause are complex and no obvious season variability can be observed. However, in the PNJ, the higher region, only obvious quasi 10-day and 16-day PWs remain, with smaller amplitudes than those around the tropopause. And significant PWs in the PNJ occur only in winter. By calculating the refractive index for PWs, it is found that there is a persistent reflection layer around 11 km, which is thick in summer and becomes thin or even disappears in winter, revealing that PWs in the stratosphere can only occur in winter. PWs in the 2003/2004 winter at the three stations are analyzed in detail. It is found that for the focused observation duration, the quasi 10-day and quasi 16-day waves exist mainly in the troposphere and stratosphere, respectively. The quasi 10-day wave is a standing wave in the vertical direction, with vertical wavelength about 12 km in the temperature component and larger than 26 km in the meridional component. Moreover, the tropospheric quasi 10-day wave propagates westward with the zonal numbers between 2 an

关键词： planetary waves troposphere and lower stratosphere radiosonde

Photochromic Azo Polysemicarbazides with Biocompatibility Behavior

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Journal of wuhan university of Technology(Materials Science) 2010年第6期25卷 979-983页

作者：刘芸熊传溪 School of Materials Science and Engineering Wuhan University of Technology state key laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of Technology

Two kinds of azo polysemicarbazides were prepared based on 3,3＇-azobis（benzoylhydrazide）（ABH） and two kinds of diisocyanates via solution *** structures were characterized by Fourier-transform infrared（FT-IR） technique and elemental *** viscosities of the polymers were 0.32 and 0.29 dL/g and both could be dissolved in H2SO4 and polar organic *** gravimetric analysis（TGA） presented a multi-step degradation and a decomposition temperature range of 230-280 ℃.And photoisomerization of the azo polymers in solvent of N,N-dimethyl acetamide（DMAc） was confirmed by Ultraviolet-visible spectroscopy（UV-Vis）,suggested the isomerization appearing under the ultraviolet irradiation at 365 nm and recovering completely by visible light irradiation or kept in the *** electron microscopy（TEM） of polysemicarbazides before and after soaking in bovine serum albumin（BSA） solution confirmed the biocompatibility of azo polymers.

关键词： azo polysemicarbazides isomerization photochromism biocompatibility