2014年于田7.3级地震的发震构造及动力学背景的初步分析

2004年2月12日新疆维吾尔自治区于田县发生了Ms7.3级地震,其发震断裂为阿尔金断裂带西南段的贡嘎错断裂带.由于地处高山无人区,存在区域历史地震漏记,但1970年以来5级以上地震活动是完整的,近20年来强震活动增强.综合分析认为,2008年于田Ms7.3地震可能加速了本次地震的发生.根据经验统计关系估计,2014年于田地震的同震地表破裂为30-40km,最大水平位错量为1.0-1.5m,地震的复发周期为300-400年.通过阿尔金断裂上前人资料和区域构造的综合分析,认为2014年于田地震是在青藏高原向北东运动背景下左旋走滑的阿尔金断裂向南西端扩展的结果.     

国外工业联系研究的理论发展及其对我国的借鉴意义

本文主要探讨了西方工业地理学关于工业联系研究的理论进展、发展背景和它所涉及的主要问题。在第二部分,着重对我国新时期条件下工业联系研究的可能性和必要性进行了讨论。其中特别是对我国现阶段生产组织形式的某些变化和西方国家作了对比,并就我国工业联系研究的某些可能领域及其意义作了论述。     

多时相耕地覆盖提取和变化分析：一种结合遥感和空间统计的时空上下文方法

基于多时相影像的耕地提取和变化分析是有效管理和保护耕地资源的重要手段。然而就多时相耕地的分类提取而言,现有方法对于多时相影像中地物的时空特征表达和时空上下文关系建模存在着局限性,导致耕地的提取精度不佳;其次,对于耕地的变化分析,现有方法往往只关注基于行政单元的耕地面积统计变化,而对耕地变化在空间上的相关性分布特点考虑较少。因此,本文首先提出了一种时空上下文分类方法,综合表达和利用多时相影像中地物的光谱、纹理和空间等特征,建模时空维度上地物间在特征和语义上的上下文关系,来提高耕地覆盖分类的精度;其次,基于耕地覆盖的提取结果,在规则格网和行政区划单元上,采用GIS空间统计方法分析耕地变化的空间相关性特点;最后,以北京市顺义区为例,以2015—2019年的多时相Sentinel-2影像为数据源对本文方法进行验证。结果表明,与常见的2种多时相影像分类方法相比,本文方法在多时相耕地分类上精度最高,平均用户精度和制图精度分别达到91.21%和90.53%,所有类别的总体精度为90.79%。这表明本文方法能精确提取多时相耕地覆盖信息。通过对耕地变化的空间分布特点进行分析,发现2015—2019年顺义...     

基于本体的地球空间信息上下文建模

总结分析了典型的地球空间信息上下文,基于本体建立了面向地球空间信息服务形式化的上下文信息模型,该模型采用层次化的设计方法,并使用本体描述语言OWL描述上下文,提高了上下文表达能力。最后,设计了一个面向地球空间信息的上下文感知计算模型。     

The rise of venture capital centres in China: A spatial and network analysis

Due to the importance of venture capital (VC) firms in spurring regional economic growth, the geography of VC firms and VC investments have attracted a lot of attention. However, the spatial patterns of cross-regional VC flows have rarely been explored, particularly in the context of emerging economies. Drawing on a unique dataset on VC firms and investments related to domestic initial public offerings (IPOs), this study combines location analysis with network analysis to investigate the spatial patterns of VC activities in China. The results confirm that Beijing, Shenzhen and Shanghai are the leading VC centres in the country. Although Yangtze Delta Area hosts the largest number of investments, Beijing and Shenzhen have a considerable advantage over Shanghai in terms of the number of VC firms, investments, and the number of domestic VC-backed IPOs. Beijing and Shenzhen also appear more central than Shanghai in China’s VC networks, with Beijing-Shenzhen representing the most important city-dyad in terms of VC investment flows. The article explains how the dynamics of the VC centres is embedded in China’s institutional and cultural context, critical to understanding the evolution and geography of China’s VC industry.     

基于情境的位置地图表示内容研究

文章在对位置地图表示内容进行梳理、归纳和总结的基础上,对位置地图表示内容进行总体框架性设计,提出将其分为地理基础底图要素和专题叠加要素,并就各自包含的具体对象要素进行了描述。重点对位置地图情境进行分类分级,分别构建活动情境、行为情境、操作情境与位置地图表示内容的关系。最后以实例对位置地图表示内容选取的实例化流程进行描述,验证文中提出并构建的各种关系模型的可行性。     

增城旅游区文脉和旅游品牌营造

对文脉的概念、组成和作用作了概述和提炼.从增城旅游资源普查而得的旅游资源单体构成中,分析和提炼出增城旅游文脉与仙姑为代表的八仙文化有不解之缘,建议建设增城神仙文化总体旅游品牌,营造"北有蓬莱三岛,南有增城九重"的八仙文化氛围,恢复、重建一些有历史文化价值的景区景点.围绕增城古老而深厚的文化底蕴进行资源整合,打造一批"来此必游"的旅游产品.     

基于描述逻辑本体的GIS多重表达

多重表达是地理信息弹性表达和弹性存取的一个内在要求,它实质上提供了一个多尺度、多应用主题的数据集成机制。多重表达的建模不能仅限于数据库中多重几何特征的一致性表达,还必须支持不同语义粒度、不同应用主题下语义特征的弹性描述。基于形式化本体的地理信息建模更贴近于认知模型,还有助于语义表达以及基于语义的信息集成和共享。通过经典描述逻辑中具体域以及context的扩展,满足区域拓扑和上下文语义形式化描述的需要;给出一个基于描述逻辑的多表达地理本体方案,该方案能够为数据库中几何信息和语义信息的弹性表达提供一个统一的基于逻辑的模型理论基础。     

Local spatial context measurements used to explore the relationship between land cover and land use functions

Research making use of satellite data for land change science has developed in the last decades. However, analysis of land use has not developed with the same speed as development of new satellite sensors and available land cover data. Improvement of land use analysis is possible, but more advanced methods are needed which make it possible to link image data to analysis of land use functions. To make this linking possible, variable which affect farmer's long term decisions must be taken into account in analysis as well as the relative importance of the landscape itself.A GIS-based tool for the measurement of local spatial context in satellite data is presented in this paper and used to explore the relationship between land covers present in satellite data and land use represented in official databases. By the use of the developed tool, a land configuration image (LCI) over the Siljan area in northern Sweden was produced and used for analysis. The results are twofold. First, the produced LCI holds new information about variables that are relevant for the interpretation of land use. Second, the comparison with statistics of agricultural production shows that production in the study area varies depending on the relative land configuration. Villages consisting of relatively large-scale arable fields and less diverse landscape are less diverse in production than villages which consist of smaller-scale and more heterogonous landscapes. The result is especially relevant for land use studies and policymakers working on environmental and agricultural policies. We conclude that local spatial context is an endogenous variable in the relation between landscape configuration and agricultural land use.     

Automated geographic context analysis for volunteered information

Several studies show the impacts of (geo)social media and Volunteered Geographic Information (VGI) during crisis events, and have found intrinsic value for rescue teams, relief workers and humanitarian assistance coordinators, as well as the affected population. The main challenge is how emergency management and the public can capitalize on the abundance of this new source of information by reducing the volume to credible and relevant content.In this paper, we present the GeoCONAVI (Geographic CONtext Analysis for Volunteered Information) approach and a prototype system, designed to retrieve, process, analyze and evaluate social media content on forest fires, producing relevant, credible and actionable VGI usable for crisis events. The novelty of the approach lies in the enrichment of the content with additional geographic context information, and use of spatio-temporal clustering to support scoring and validation. Thus, the system is focusing on integrating authoritative data sources with VGI. Evaluation in case studies shows that the prototype system can handle large amounts of data with common-off-the-shelf hardware, produces valuable results, and is adaptable to other types of crisis events.