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1.
为评估CWRF模式的降尺度能力和其热带气旋模拟对物理参数化方案的敏感性,本文利用ERI再分析资料驱动CWRF在30km网格上对1982-2016年中国近海热带气旋开展了一次集合模拟.结果表明:CWRF与ERI均能模拟出热带气旋的季节变化和年际变化形势且均存在低估,但相较ERI,CWRF的降尺度技术和集合模拟可以再现更多的热带气旋,显著减少低估.年际变化结果提升最为明显,它对积云方案最为敏感,其次是边界层,陆面和辐射方案,对云和微物理方案较弱.该研究为应用CWRF理解和预报热带气旋提供了参考.  相似文献   
2.
Sun  Wei  Li  Qihang  Li  Bo 《地理学报(英文版)》2019,29(12):1965-1980
Journal of Geographical Sciences - As information technology has been applied more broadly and transportation infrastructure has improved, persistent debate has existed as to the question of...  相似文献   
3.
Despite several decades of discussion and debate around the role of GIS in the discipline of Geography, it would be a stretch to argue that GIS has not irreversibly altered the discipline, both in the scope of research and teaching as well as in the wider imagination of a general public. However, it remains a challenge to incorporate the range of geographic knowledge, born of a diversity of modalities, into operational insights and analytical pre‐conditions in a GIS. To be certain, some irreconcilability between GIS and geographical inquiry is to be expected, epistemologically speaking. In what follows, we consider what might be meant by a shift to geographic analysis as scholars from disciplines in the humanities and social sciences turn to GIS as a method of observation, interpretation, analysis, and representation. In this context, we engage in a thought experiment and offer some commentary, fixing the notion of information system, while opening the geographic in GIS to more variable understanding. The point is to pursue greater development of GIS theory and method, encompassing, while not reducing, scientific, social scientific, and humanities research.  相似文献   
4.
ABSTRACT

The importance of including a contextual underpinning to the spatial analysis of social data is gaining traction in the spatial science community. The challenge, though, is how to capture these data in a rigorous manner that is translational. One method that has shown promise in achieving this aim is the spatial video geonarrative (SVG), and in this paper we pose questions that advance the science of geonarratives through a case study of criminal ex-offenders. Eleven ex-offenders provided sketch maps and SVGs identifying high-crime areas of their community. Wordmapper software was used to map and classify the SVG content; its spatial filter extension was used for hot spot mapping with statistical significance tested using Monte Carlo simulations. Then, each subject’s sketch map and SVG were compared. Results reveal that SVGs consistently produce finer spatial-scale data and more locations of relevance than the sketch maps. SVGs also provide explanation of spatial-temporal processes and causal mechanisms linked to specific places, which are not evident in the sketch maps. SVG can be a rigorous translational method for collecting data on the geographic context of many phenomena. Therefore, this paper makes an important advance in understanding how environmentally immersive methods contribute to the understanding of geographic context.  相似文献   
5.
ABSTRACT

More than 10 years have passed since the coining of the term volunteered geographic information (VGI) in 2007. This article presents the results of a review of the literature concerning VGI. A total of 346 articles published in 24 international refereed journals in GIScience between 2007 and 2017 have been reviewed. The review has uncovered varying levels of popularity of VGI research over space and time, and varying interests in various sources of VGI (e.g. OpenStreetMap) and VGI-related terms (e.g. user-generated content) that point to the multi-perspective nature of VGI. Content-wise, using latent Dirichlet allocation (LDA), this study has extracted 50 specific research topics pertinent to VGI. The 50 topics have been subsequently clustered into 13 intermediate topics and three overarching themes to allow a hierarchical topic review. The overarching VGI research themes include (1) VGI contributions and contributors, (2) main fields applying VGI, and (3) conceptions and envisions. The review of the articles under the three themes has revealed the progress and the points that demand attention regarding the individual topics. This article also discusses the areas that the existing research has not yet adequately explored and proposes an agenda for potential future research endeavors.  相似文献   
6.
虚拟地理环境对人类理解、探索地理现象以及发现地理现象之间的联系起到很重要的作用。在基于VR技术的虚拟地理环境中更高效,更自然的交互对虚拟地理环境系统的可用性以及理解、探索地理现象的效率至关重要。当前,人机交互中更自然便捷的交互依赖于动作捕捉技术,而现有的基于单种捕捉模式的动作捕捉方式,易受到遮挡、定位漂移等的影响,捕捉精度受到限制,并只能捕捉单个人的动作,不能满足虚拟地理环境对动作捕捉技术提出的特殊需求。针对单种模式的动作捕捉设备应用于虚拟地理环境受到的限制,本文分析了虚拟地理环境系统中的交互需求以及其对动作捕捉技术提出的特殊需求,创新性的提出了一种基于多种动作捕捉模式以捕捉多人动作的方法。本文方法集中于如何融合基于多种模式的多台设备的动作数据,描述了多人动作捕捉框架及其涉及到的技术,在动作捕捉效果上具有明显提升,能够捕捉多人动作,并开发了原型系统对此方法进行了验证。  相似文献   
7.
热力图是一种能直观准确展示空间观测值的有效工具,在多个领域具有广泛应用。本文在分析设定不同道路层权重、道路技术等级分类的基础上,以反距离权重、直方图均衡化、密度补偿、参数多次迭代等方法,研究构建了以热力方式展示道路网分布及发达程度的相关规则体系。热力规则通过道路赋权、路线曲面化、密度协调、图面综合等多套规则的有机结合,实现了道路网总体发达水平信息的提取与展示,并以全球地理信息资源建设项目路网成果中的亚洲和非洲部分国家数据为例,进行了信息提取与热力分布试验。  相似文献   
8.
随着信息技术的发展和GIS的实际发展需求的增加,GIS逐渐转向了三维地理信息网络服务方向。在满足GIS服务发展需求的基础上,三维地理信息网络服务为空间信息的高效集成的实现作出了重要贡献。本文综述了三维地理信息网络服务的发展情况,并提出了存在的问题及相应的建议,以供参考。  相似文献   
9.
首先分析了目前传统外业调绘及外业调绘系统普遍存在的问题,随后提出了一种"基于北斗导航定位技术的通用型自然资源实地调查信息系统"的信息化技术解决方案,并对该方案的设计原则、总体架构进行了描述。最后,详细地分析了该技术方案涉及的关键技术。本文旨在为自然资源实地调查工作带来全新信息化作业模式,提出一套探索思路,贡献一份力量。  相似文献   
10.
The aim of this article is to introduce the Beach Crowding Index (BCI), a procedure to assess the social carrying capacity of vulnerable beaches. The study uses the people at one time (PAOT) approach and data gathered weekly throughout the bathing season regarding the number of beachgoers in 100 m2 cells of the beach to assess how many beachgoers it can comfortably hold. The procedure is based on fieldwork, interviews with beachgoers, and geographic information system (GIS) analysis and has been tested on four beaches in protected areas on the Spanish Mediterranean coast. On a scale from 0 to 4, minimum scores throughout the bathing season are 0.7 and maximum 3.7, although results showed wide variation between the beaches, the section of the beach, and the time of day. This study suggests that determining the location of beachgoers and collecting a long-term series of data is fundamental to assessing social carrying capacity and that the BCI procedure can be used for a large number of applications.  相似文献   
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