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11.
Animated choropleth maps enable cartographers to visualize time-series data in a way that congruently depicts change over time. However, users have difficulty apprehending information encoded within these displays, and often fail to detect important changes between adjacent scenes. Failures of visual experience, such as change blindness, threaten the effectiveness of dynamic geovisual displays, in which several important changes can occur simultaneously throughout the display. Animated choropleth maps require viewers not only to notice changes but also understand symbolic meanings encoded in rapid transitions between scenes. Graphic interpolation between key frames, also known as “in-betweening” or “tweening”, smoothes transitions and lengthens the duration of the transition between scenes in a dynamic sequence. Previous cartographic literature suggests tweening could be a potential solution for change blindness in the cartographic context. This article examines this issue of change blindness in the cartographic context and reports on a human subjects investigation designed to evaluate the influence of cartographic design variables on map readers' change detection abilities. Our results indicate that 1) map readers have difficulty detecting changes in animated choropleth maps, 2) map readers over-estimate their own change detection abilities, and 3) tweening influences the legibility of change in animated choropleth maps.  相似文献   
12.
2003年汛期3种中尺度数值预报模式降水预报检验   总被引:7,自引:0,他引:7  
利用2003年汛期降水实况及河南省气象台引进的3种中尺度数值预报模式(REM、MM5、MAPS)的降水预报资料,对模式预报性能作了检验对比分析。结果发现:REM模式对于大雨以上降水的预报效果较好;MAPS模式的12h预报有明显优势;MM5模式对小雨和中雨的预报效果较好,并且预报结果具有稳定性。  相似文献   
13.
中尺度和云模式嵌套试验   总被引:1,自引:0,他引:1  
万蓉  李劲  王志斌 《气象》2006,32(5):16-21
利用嵌套Mesoscale Analysisand Process System(MAPS)模式提供离作业时间最近的湖北省77个县站大气层结状况,以弥补积云模式对于探空层结信息的需求;根据天气类型分析,获取湖北全省县站级一维积云模式初始扰动参数。20次嵌套试验统计表明:中尺度MAPS模式和积云模式的嵌套实现了多站点积云群的模拟,县站级降水预报和实际雨量偏差小于20%的站点数占到总数的58.2%;以2003年7月9日湖北省降水为例,利用嵌套模式对全省77个县站进行嵌套试验,结果表明:模式嵌套尤其有利于午后积云降水模拟,通过自然模拟计算和多站点积云群催化对比分析,能够较好地提供县站级增雨潜势量化预测。  相似文献   
14.
The purpose of this paper is to describe an automated geographic information system (GIS) process to estimate the length of pipeline required to provide utility service to a potential customer base using the street rights-of way. Using a case study application for a large gas utility company, we compare this method to the traditional method based on straight-line Euclidean, or as-the-crow-flies, distances. The GIS method using the street rights-of-way provides a substantially more accurate estimate of the length of required pipeline than the as-the-crow-flies method does. The improvement is particularly significant when the potential customers are located a substantial distance from existing pipelines. With improved estimates of required pipeline length, utilities can pre-qualify potential customers for marketing opportunities.  相似文献   
15.
A Bidirectional Hermitian Spline (BHS) method for the estimation of point values from isoline maps is presented and compared to three other methods. Hermitian splines are used and first derivatives are estimated by either Akima's method or by a clamped cubic spline, if Akima's method returns a zero first derivative. Every desired point value is interpolated twice, once by each of two orthogonally-directed splines. The two spline estimates are then averaged using the error formula for Hermitian splines. In addition, a periodic Hermitian spline is constructed around the study-area perimeter (representing a cross-sectional profile of the edge) to damp undesirable edge effects. Point values can be estimated from small-scale isoline maps drawn in spherical coordinates or from large-scale isoline maps drawn in Cartesian coordinates.  相似文献   
16.
The purpose of this research was to examine the interaction between color and the visual processes people use to search choropleth maps. Two experiments were performed in which subjects searched hypothetical choropleth maps displayed on a cathode-ray tube to determine whether a particular (target) boundary formed by two adjacent polygons filled with different colors was present. In experiment 1, the four pairs of colors used to form the target boundaries were red-blue, green-yellow, green-magenta, and cyan-magenta. In experiment 2, red-green, blue-yellow, red-orange, and cyan-orange were the color pairs used toform the target boundaries. The target boundary colors, target-background discriminability, target boundary location, and the number and types of boundaries on the maps had a significant effect on search time. The results of both experiments indicated that subjects were using a parallel search process followed by a serial search process as described by Cave and Wolfe's (1990) guided search theory. The relative mean search times for the various colored target boundaries was best explained by the opponent process theory.  相似文献   
17.
The MAPS Programme has been active in Brazil, Chile, Colombia and Peru in supporting the development of an evidence base to inform the processes involved in climate mitigation policy-making. The programme combines detailed quantitative analysis with an extensive stakeholder engagement process to provide policy and decision makers with the information required for long-term climate mitigation planning.

In recognition of the critical need to consider the developmental context and agenda in climate policy-making, the projects undertaken in these countries have experimented with various types of assessments of developmental impacts at both the macro and micro levels. These impacts have been collectively termed co-impacts to reflect the fact that these may be either positive or negative. In this article the value and challenges associated with co-impacts work for climate mitigation policy are considered. The value of including co-impacts analysis in the MAPS processes included increased stakeholder buy-in, making the case for mitigation action, informing INDCs and the prioritization of particular mitigation actions. Challenges include those associated with obtaining locally relevant data, the selection and operation of appropriate macro-economic models and analytical approaches and working with multidisciplinary teams.

The article concludes by making some suggestions to optimize co-impacts work, through reference to other bodies of literature. The authors highlight that this article is situated within a dominant approach to climate mitigation policy work in developing countries, which implicitly places the non-climate benefits of any action as secondary to the primary benefit of climate change mitigation and constructs an artificial separation of policy formulation and implementation. Practitioners are encouraged to reflect on the implications of these considerations in future efforts.

Policy relevance

One of the primary challenges to advancing climate mitigation policy in developing countries is that of perceived relevance: near-term development priorities are overwhelming. Identifying, understanding and engaging with the co-impacts of mitigation actions has emerged as one way of addressing this challenge. Although still at an experimental phase, experience with co-impacts analysis in the MAPS countries provides some useful lessons in how to develop this area of work.  相似文献   
18.
Abstract

This paper describes a methodology for evaluating the planimetric accuracy of three US Civil War maps using GIS and spatial analytical techniques. The case-study is the Battle of Stones River in Tennessee and, in particular, maps depicting the events of December 31, 1862. An examination of the objectives, limitations and techniques employed by the topographer engineers who created the maps provides focus for the quantitative analysis and establishes the historical context needed to understand how and why the maps were constructed. The paper shows how GIS and spatial analysis can be utilized to document vanishing historic landscapes and reconstructing where certain historical events took place.  相似文献   
19.
《The Cartographic journal》2013,50(3):239-250
Abstract

Since the early 1980s, we have seen a new influx of numerous geopolitical atlases. They have been produced to meet society's implicit need to fix the boundaries of international issues and the relationships of force between the various powers. These atlases clearly express established ideologies and allow us to determine various trends of thought; messages which the authors wish us to take on board by studying cartographic themes. This is the approach we will be taking in this article.

In this paper, we aim to show the epistemological development of geopolitical atlases. The first part of the article gives the general outline of the epistemological development of geopolitical atlases, in which two main periods stand out. The first corresponds with the 1980s, which can be described as a realist decade. The state was a geopolitical player that could not be overlooked within a bipolar world; maps showing conflicts between the two major powers and thematic maps showing an ideological clash between them are typical of the period. The second period, corresponding with the 1990s, begins with the fall of the regimes in the Soviet bloc. This period can be described as having a neo-realist approach, where the threat from the East had moved to terrorism and drug trafficking. The atlases follow the geopolitical development of the world and describe international structural changes. In conclusion, the paper will return to the important educational and informative role of atlases and their effects on the ideas they are able to disseminate amongst the population.  相似文献   
20.
Gringonen's square equal-area map projection has been forgotten since its appearance in 1972. I describe a modern implementation, including details of how to arrange, in different ways, the fundamental Gringonen projection of a sexadecant (one sixteenth of the surface of the sphere) onto a triangle. The Gringorten Mark I projection is an arrangement in which one hemisphere forms a square, with the other hemisphere disposed around it so that the whole sphere projects as a diamond, which may then be rotated to appear as a square. I introduce an alternative arrangement, the Gringorten Mark II, which is twice as high as it is wide, with one hemisphere on top of the other. These variants are compared with some other square map projections. Maps that fill a rectangular space completely can be very useful where, as on computer screens, space is limited and must be used efficiently.  相似文献   
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