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981.
多重空间数据因其可用性及几何和主题方面的质量差异,催生了针对数据挖掘方法研究的新系统开发,其中包括了异构空间数据结构分析与改进的处理进程。本文介绍了空间数据融合系统( DAFU)的概念、架构与功能性方面的内容,DAFU能够有效使用异构空间数据信息并可进行地理数据的个体使用。 相似文献
982.
分析了数字化地理信息数据生产和管理的现状,从数据生产组织管理模式、数据管理和服务模式两方面阐述了目前基础地理空间数据的生产管理和数据共享中存在的问题。提出了面向测绘地理信息数据生产加工、以基础地理空间数据库为核心的数据管理和服务技术体系,采用C/S模式分布式体系结构进行系统功能设计,建立信息化测绘的多源测绘产品管理系统。 相似文献
983.
邓开艳 《测绘与空间地理信息》2013,36(7):136-138,141
探讨了GeoGlobe3维GIS技术在基础测绘成果客户选图服务中的应用,主要包括系统框架设计和具体功能。 相似文献
984.
高精度3维激光扫描技术的出现,为建立一套覆盖完整、细节清晰、视觉效果突出、数据真实准确的数字石窟提供了可能。云冈石窟3维数字化工作就是将3维激光扫描技术应用到石窟的制作,利用激光测距原理,以最精细、最合理的技术手段记录石窟的密集点的3维坐标、反射率和纹理等信息,完整保留全面、准确、细致的3维数据,进而复建出石窟的3维模型及线、面、体等各种数据,将云冈石窟清晰地展现出来。 相似文献
985.
近年来,我院开展以“采编一体、内外一体、图库一体”为核心的信息化测绘生产体系建设,航测生产流程再造工作是关键所在。这就要求航测外业调绘要满足内外一体化的要求,实现外业调绘信息的快速、高效录入,减少繁琐作业环节(编辑打印调绘片、外业清绘调绘片、内业转绘调绘成果)实现外业调绘信息的数字化,这也是提高生产效率和降低作业成本的核心技术之一。针对野外测量生产信息化的薄弱环节,我院通过使用GEOWAY Fielder数字调绘系统,大大提高了野外调绘的工作效率,解决了新增地物标绘的精度问题,为数字化图生产与建库的前端数据采集提供了新方法。本文主要介绍了GEOWAY Fielder数字调绘系统在我院基础测绘1∶10000数字线划图生产中的应用,总结出数字调绘系统定位精度及数字调绘系统的优势和实际应用中应注意的问题。 相似文献
986.
987.
《International Journal of Digital Earth》2013,6(9):1046-1066
ABSTRACTTo analyze the efficiency of area estimations (i.e. estimation accuracy and variation of estimation) impacted by crop mapping error, we simulated error at eight levels for thematic maps using a stratified sampling estimation methodology. The results show that the estimation efficiency is influenced by the combination of the sample size and the error level. Evaluating the trade-offs between sample size and error level showed that reducing the crop mapping error level provides the most benefit (i.e. higher estimation efficiency). Further, sampling performance differed based on the heterogeneity of the crop area. The results demonstrated that the influence of increasing the error level on estimation efficiency is more detrimental in heterogeneous areas than in homogeneous ones. Therefore, to obtain higher estimation efficiency, a larger sample size and lower error level or both are needed, especially in heterogeneous areas. We suggest that existing land-cover maps should first be used to determine the heterogeneity of the area. The appropriate sample size for these areas then can be determined according to all three factors: heterogeneity, expected estimation efficiency, and sampling budget. Overall, extending our understanding of the impacts of crop mapping error is necessary for decision making to improve our ability to effectively estimate crop area. 相似文献
988.
《International Journal of Digital Earth》2013,6(11):861-876
OpenStreetMap (OSM) has seen an exponential increase in the last few years and large volumes of geodata have been received from volunteered individuals. The collected geodata are heterogeneous in terms of different dimensions such as spatial patterns of contributions, quality, patterns of contributing individuals, and type of contributions. Because contributors’ personal information is anonymously stored by the OSM administrators, alternative methods are needed to investigate the role of contributors’ characteristics on their mapping behavior. This study is intended to explore the potential socio-economic characteristics of contributors in highly contributed areas to have better insights about the latent patterns of involved individuals in a highly dynamic state of the most active country in OSM, Germany. A logistic regression model (LRM) is applied to discover the potential correlations between dependent and independent variables. The findings explain that the areas with high population density, middle level of education, high income, high rate of overnight stays, high number of foreigners, and residents aged from 18 to 69 are more likely to be involved in OSM. Furthermore, the degree of dynamism in OSM is a function of proximity to built-up areas. Finally, concluding remarks concerning the independent variables and model sensitivity are presented. 相似文献
989.
none 《The Cartographic journal》2013,50(2):112-116
AbstractUsing examples from the governmental, commercial and educational sectors, the development of photo maps and mapping using satellite imagery is outlined. The emphasis of this paper is on the design possibilities and limitations which are evident in these products. Contrast and legibility problems and image clutter are considered, but it is concluded that the institutional impediments to the collaboration of specialists in researching and designing such maps may be of most importance in determining progress in the use of such maps. 相似文献
990.
《The Cartographic journal》2013,50(2):144-156
AbstractIsolines have proved to be a highly effective way of conveying the shape of a surface (most commonly in the form of height contours to convey geographical landscape). Selecting the right contour interval is a compromise between showing sufficient detail in flat regions, whilst avoiding excessive crowding of lines in steep and morphologically complex areas. The traditional way of avoiding coalescence and confusion across steep regions has been to manually remove short sections of intermediate contours, while retaining index contours. Incorporating humans in automated environments is not viable. This research reports on the design, implementation and evaluation of an automated solution to this problem involving the automatic identification of coalescing lines, and removal of line segments to ensure clarity in the interpretation of contour information. Evaluation was made by subjective comparison with Ordnance Survey products. The results were found to be very close to the quality associated with manual techniques. 相似文献