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数据仓库及其设计规范化 被引量:13
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作者 马刚 王延章 《大连理工大学学报》 CAS CSCD 北大核心 2001年第5期626-630,共5页
在严格数据仓库概念基础上 ,说明了数据仓库与多维数据库之间关系及数据仓库的特性和优势 .重点讨论并给出了一种规范化的数据仓库设计和粒度模型设计方法 .粒度设计在数据仓库建模中十分重要 ,实质上 ,它在数据仓库模型设计的一些重要... 在严格数据仓库概念基础上 ,说明了数据仓库与多维数据库之间关系及数据仓库的特性和优势 .重点讨论并给出了一种规范化的数据仓库设计和粒度模型设计方法 .粒度设计在数据仓库建模中十分重要 ,实质上 ,它在数据仓库模型设计的一些重要指标间提供了一项交换技术 ,以保证数据仓库系统结构稳定、存储与访问性能良好 ,但粒度设计往往凭经验调试完成 .根据专家系统技术 ,提出一种动态粒度划分方法 。 展开更多
关键词 数据库 数据仓库 多维数据库 信息包图 粒度模型 规范化设计
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A NOVEL ALGORITHM OF MULTI-SENSOR IMAGE FUSION BASED ON WAVELET PACKET TRANSFORM 被引量:3
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作者 Cheng Yinglei Zhao Rongchun +1 位作者 Hu Fuyuan Li Ying 《Journal of Electronics(China)》 2006年第2期314-317,共4页
In order to enhance the image information from multi-sensor and to improve the abilities of the information analysis and the feature extraction, this letter proposed a new fusion approach in pixel level by means of th... In order to enhance the image information from multi-sensor and to improve the abilities of the information analysis and the feature extraction, this letter proposed a new fusion approach in pixel level by means of the Wavelet Packet Transform (WPT). The WPT is able to decompose an image into low frequency band and high frequency band in higher scale. It offers a more precise method for image analysis than Wavelet Transform (WT). Firstly, the proposed approach employs HIS (Hue, Intensity, Saturation) transform to obtain the intensity component of CBERS (China-Brazil Earth Resource Satellite) multi-spectral image. Then WPT transform is employed to decompose the intensity component and SPOT (Systeme Pour I'Observation de la Therre ) image into low frequency band and high frequency band in three levels. Next, two high frequency coefficients and low frequency coefficients of the images are combined by linear weighting strategies. Finally, the fused image is obtained with inverse WPT and inverse HIS. The results show the new approach can fuse details of input image successfully, and thereby can obtain a more satisfactory result than that of HM (Histogram Matched)-based fusion algorithm and WT-based fusion approach. 展开更多
关键词 Wavelet Transform (WT) Wavelet Packet Transform (WPT) Image fusion High frequency information Low frequency information
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Approaches to Census Mapping:Chinese Solution in 2010 Rounded Census 被引量:5
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作者 WANG Yingjie LI Hongsheng +1 位作者 YU Zhuoyuan LUO Bin 《Chinese Geographical Science》 SCIE CSCD 2012年第3期356-366,共11页
China still use sketch maps as control devices that guarantees consistency and accuracy of population counting in previous census.Although the rapid advancement of geospatial technologies provides many possible soluti... China still use sketch maps as control devices that guarantees consistency and accuracy of population counting in previous census.Although the rapid advancement of geospatial technologies provides many possible solutions of digital census mapping,existing researches do not answer which solution is suitable to China.Subject to many constraints originated from characteristics of China,a practical solution of census mapping based on remote sensing imagery and auxiliary geographic information was proposed and proved to be feasible through evaluation analysis and a three-stage pilot study.Imagery with 2.5 meters and higher resolution,innovative workflow of census areas delineation,easy-to-use census mapping software packages and training organization all together provide the all-around supports for the 2010 rounded census (the 6th census) mapping activities.A digital census geographic framework detailed at the level of enumeration area was established in the 2010 rounded census which fills in the gaps in the field of modern geospatial census in China.The spatially referenced digital census database,especially the detailed census units,is of great value in successive census,sampling survey and many other census-related fields.Future work including quality evaluation of census areas,census mapping solution in the Tibet Autonomous Region are also discussed. 展开更多
关键词 6th census census mapping Chinese solution geographic information system remote sensing
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