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51.
Terrain Pattern Recognition and Spatial Decision Making for Regional Slope Stability Studies 总被引:1,自引:0,他引:1
George?MiliaresisEmail author Nikos?Sabatakakis George?Koukis 《Natural Resources Research》2005,14(2):91-100
A terrain partition scheme is presented that allows the identification of regions with high landslide risk in natural terrain zones on the basis of geomorphometric criteria from moderate resolution DEMs. The key factor being the terrain segmentation to aspect regions (regions formed by points preserving the same aspect direction) instead of using an artificial regular-grid terrain partition scheme. The study area is in western Greece (NW Peloponnesus) whereas a moderate resolution digital elevation model with spacing 75 m is used. Landslide inventory analysis and knowledge conceptualization identified that the landslide susceptibility of a particular aspect region is high, if the mean elevation is low and the mean gradient is high. Each aspect region was parametrically represented on the basis of its mean gradient and elevation. The domain of each parameter was divided to seven slices (classes) on the basis of the observed density. Subsequent knowledge based mapping identified aspect regions with high landslide susceptibility for the following spatial rule: (a) “mean slope in class 6 or 7” and (b) “mean elevation in class 1 to 5”. Alternatively the rule is expressed as mean slope to be equal or greater than 15∘ whereas mean elevation to be in the range 0 to 750 m. These identified zones correspond to regions where historical landslides occurred (populated coastal areas in the North) as well as to south regions (natural terrain zone) where no landslide record is available, because of the limitations posed by the natural terrain landslide mapping program in Greece. The presented terrain segmentation technique combined to the spatial decision-making process, provided both an object framework for integrating geomorphometric parameters and a method for landslide risk analysis in natural terrain zones. 相似文献
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《The Journal of geography》2012,111(2):70-76
This study investigates the location and varying spatiality of questions in geography textbooks. The results show that study questions posed in page margins address the three components of spatial thinking—concepts of space, using tools of representation, and processes of reasoning—more than questions in other locations within the text. Three practices are particularly recommended to help students develop spatial thinking skills through answering textbook questions: (1) utilize page-margin questions; (2) select questions around spatial representations; and (3) focus on higher-level cognitive processes. 相似文献
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《The Journal of geography》2012,111(4-5):213-227
Abstract This article suggests how teachers can approach the Internet conceptually and use it practically as they teach about the American South. Because of its information, communication, and cultural dimensions, the Internet represents a “place” where students and teachers can appraise the South from multiple, alternative perspectives. The article offers lesson strategies and resources for both on-computer and off-computer classroom settings. By finding the southern part of cyberspace, the authors illustrate that regions can and do have a place in a medium often represented as spaceless and devoid of geographic boundaries. 相似文献
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《The Journal of geography》2012,111(5):208-219
ABSTRACTGeography textbooks contain chapter or review questions that may engage students in spatial thinking. This research used Jo and Bednarz’s (2009) Taxonomy of Spatial Thinking to evaluate the percentage of spatial thinking questions in four university-level world geography course textbooks. The results from this study were then compared to the findings in Jo and Bednarz’s (2009) analysis of high school geography textbooks. Thirty-five percent of university level textbook questions are related to spatial thinking compared to twenty-four percent in high school geography textbooks. The results provide information useful to stakeholders, such as teachers, administrators, and textbook writers and may help these stakeholders to consciously incorporate the three components of spatial thinking as defined by the National Research Council (2006). A simplified taxonomy for identifying spatial-thinking concepts in textbook review questions is also suggested. 相似文献
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《The Journal of geography》2012,111(5):188-196
This article provides a history of efforts to map vernacular regions as context for offering readers a way of using business directories in order to construct a GIS-based map of vernacular regions. With Michigan as a case study, the article discusses regional-naming conventions, boundaries, and inclusions and omissions of areas from regional labels in order to offer educators ideas that can enhance classroom content on regions. This article concludes by providing suggestions for classroom activities collecting, analyzing, and discussing vernacular region patterns and processes in accordance with National Geography Standard Five at the eighth-grade level. 相似文献
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复杂地貌形态多比例尺表达的二维小波分析研究 总被引:4,自引:0,他引:4
针对复杂地貌形态的多比例尺表达中的等高线容易相交、地性特征描述困难和表达过程缺乏自适应等难题,提出了基于小波理论的复杂地貌形态的多比例尺表达模型,为上述问题的解决提供了新的思路和有效途径。 相似文献