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1.
Diversity within a population has been linked to levels of both social cohesion and crime. Neighborhood crimes are the result of a complex set of factors, one of which is weak community cohesion. This article seeks to explore the impacts of diversity on burglary crime in a range of neighborhoods, using Leeds, UK as a case study. We propose a new approach to quantifying the correlates of burglary in urban areas through the use of diversity metrics. This approach is useful in unveiling the relationship between burglary and diversity in urban communities. Specifically, we employ stepwise multiple regression models to quantify the relationships between a number of neighborhood diversity variables and burglary crime rates. The results of the analyses show that the variables that represent diversity were more significant when regressed against burglary crime rates than standard socio‐demographic data traditionally used in crime studies, which do not generally use diversity variables. The findings of this study highlight the importance of neighborhood cohesion in the crime system, and the key place for diversity statistics in quantifying the relationships between neighborhood diversities and burglary. The study highlights the importance of policy planning aimed at encouraging community building in promoting neighborhood safety. 相似文献
2.
Maps, created through the collection, assembly, and analysis of spatial data are used to support government planning and decision-making. Traditionally, spatial data used to create maps are collected, controlled, and disseminated by government, although over time, this role has shifted. This shift has been driven by the availability of alternate sources of data collected by private sector companies, and data contributed by volunteers to open mapping platforms, such as OpenStreetMap. In theorizing this shift, we provide examples of how governments use data sovereignty as a tool to shape spatial data collection, use, and sharing. We frame four models of how governments may navigate shifting spatial data sovereignty regimes; first, with government retaining complete control over data collection; second, with government contracting a third party to provide specific data collection services, but with data ownership and dissemination responsibilities resting with government; third, with government purchasing data under terms of access set by third party data collectors, who disseminate data to several parties, and finally, with government retreating from or relinquishing data sovereignty altogether. Within this rapidly changing landscape of data providers, we propose that governments must consider how to address data sovereignty concerns to retain their ability to control data use in the public interest. 相似文献
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Glyphs are small geometric shapes that in geovisualization are often used to represent multidimensional spatial data. The aim of this study is to investigate the effectiveness of their two types – star and polyline glyphs, as they can encode the same message and can provide similar functionality. Thus, if the two glyph types are similar and can be used for the same data, the question arises as to which of them better facilitates various user tasks. To address this question, an empirical study of 26 individual users is conducted to investigate differences in user performance for polyline and star glyphs shown either in a grid plot or on a map display. In this study, a task-based approach with eye-tracking is applied, as well as a subjective questionnaire and a psychological test of cognitive style. The finding is that polyline glyphs better facilitate tasks when datapoint values in glyphs are to be read, whereas star glyphs are better when a visual search among glyphs is to be done. Moreover, the results reveal that the map display works better than the grid plot. If star glyphs are to be used, the key (legend) needs to be better incorporated into a visual interface. 相似文献
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《International Journal of Digital Earth》2013,6(4):315-325
Abstract After the set-up of a spatial data infrastructure (SDI) and a national information infrastructure (NII) in many countries, the provision of geo-services became one of the most important and attractive tasks. With the integration of global positioning system (GPS), geographic information system (GIS) and remote sensing (RS), we can, in principle, answer any geo-spatial related question: when and where what object has which changes? An intelligent geo-service agent could provide end-users with the most necessary information in the shortest time and at the lowest cost. Unfortunately there is still a long way to go to achieve such goals. The central component in such geo-services is the integration of the spatial information system with a computing grid via wire- and wireless communication networks. This paper will mainly discuss the grid technology and its integration with spatial information technology, expounding potential problems and possible resolutions. A novel categorising of information grids in the context of geo-spatial information is proposed: generalised and specialised spatial information grids. 相似文献
5.
GIScience scholars have identified map tours as an important visualization type for communicating spatial information: map tours are animations where the virtual camera moves through space and are common on the web, mobile devices, and television. Understanding how to enhance their effectiveness is timely because of recent, growing interest in virtual reality and animated map presentation tools such as Esri Story Maps? and Google Earth? tours. Despite this popularity, little empirical evidence exists about how people learn from map tours and how they should best be designed to improve effectiveness. This research is aimed at answering that need. An empirical study is described, which was designed to understand how virtual camera speed, path, and dynamic tilting within a map tour influence subjects’ ability to develop survey knowledge. The results of the experiment show that paths encompassing overviews of the landscape improve the viewer’s ability to build up survey knowledge; that tilting appears to have a much weaker effect; and that combining fast speed and a difficult path within a map tour increases the viewer’s cognitive load. 相似文献
6.
Optical image classification converts spectral data into thematic information from the spectral signature of each object in the image. However, spectral separability is influenced by intrinsic characteristics of the targets, as well as the characteristics of the images used. The classification process will present more reliable results when aspects associated with natural environments (climate, soil, relief, water, etc.) and anthropic environments (roads, constructions, urban area) begin to be considered, as they determine and guide land use and land cover (LULC). The objectives of this study are to evaluate the integration of environmental variables with spectral variables and the performance of the Random Forest algorithm in the classification of Landsat-8 OLI images, of a watershed in the Eastern Amazon, Brazil. The classification process used 96 predictive variables, involving spectral, geological, pedological, climatic and topographic data and Euclidean distances. The selection of variables to construct the predictive models was divided into two approaches: (i) data set containing only spectral variables, and (ii) set of environmental variables added to the spectral data. The variables were selected through nonlinear correlation analysis, with the Randomized Dependence Coefficient and the Recursive Feature Elimination (RFE) method, using the Random Forest classifier algorithm. The spectral variables NDVI, bands 2, 4, 5, 6 and 7 of the dry season and band 4 of the rainy season were selected in both approaches (i and ii). The Euclidean distance from the urban area, Arenosol soil class, annual precipitation, precipitation in February and precipitation of the wettest quarter were the variables selected from the auxiliary data set. This study showed that the addition of environmental data to the spectral data reduces the limitation of the latter, regarding the discrimination of the different classes of LULC, in addition to improving the accuracy of the classification. The addition of soil classes to spectral variables provided a reduction in errors for vegetation classification (Evergreen Forest and Cerrado Sensu Stricto), as it was able to inform about nutrient availability and water storage capacity. The study demonstrates that the addition of environmental variables to the spectral variables can be an alternative to improve monitoring in areas of ecotone in Neotropical regions. 相似文献
7.
Journal of Geographical Systems - The link between income inequality and economic growth remains poorly understood. The global economic crisis challenged numerous growth studies by highlighting... 相似文献
8.
Jie Cheng Shunlin Liang Aixiu Nie Qiang Liu 《Journal of the Indian Society of Remote Sensing》2018,46(4):591-596
For a satellite sensor with only one or two thermal infrared channels, it is difficult to retrieve the surface emissivity from the received emissive signal. Empirical linear relationship between surface emissivity and red reflectance are already established for deriving emissivity, but the inner physical mechanism remains unclear. The optical constants of various minerals that cover the spectral range from 0.44 to 13.5 μm in conjunction with modern radiative transfer models were used to produce corresponding surface reflectance and emissivity spectra. Compared to the commonly used empirical linear relationship, a more accurate multiple linear relationship between Landsat TM5 emissivity and optical reflectances was derived using the simulated data, which indicated the necessity of replacing the empirical relationship with the new one for improving surface emissivity estimate in the single channel algorithm. The significant multiple linear relationship between broadband emissivity (BBE, 8–13.5 μm) and MODIS spectral albedos was also derived using the same data. This paper demonstrates that there is a physical linkage between surface emissive and reflective variables, and provides a theoretical perspective on estimating surface emissivity for sensors with only one or two thermal infrared channels. 相似文献
9.
Claire Ellul 《Transactions in GIS》2012,16(4):435-454
University College London's Department of Civil, Environmental and Geomatic Engineering (CEGE) offers a number of Masters programmes in topics related to Geomatics, including Surveying, Hydrographic Surveying, Remote Sensing and Geographical Information Science. Data management, and in particular the technology and applications of Spatial Databases, forms a key part of the curriculum on these courses. Interest in Spatial Databases is, however, more widespread – especially with the increasing understanding of the relevance of geospatial techniques to fields as diverse as anthropology and architecture. This article describes the development and evaluation of a self‐paced hands‐on course on Databases and Spatial Databases for CEGE students, presented to students to complement and enhance in‐class teaching. The article focuses on both pedagogical elements of self‐paced learning and the suitability of Free and Open Source Software and Open Data (PostgreSQL/PostGIS, Quantum GIS, Open Street Map) for the Spatial Databases curriculum. The resulting material was evaluated by a cohort of 25 students in 2010, and their feedback (very positive) and the overall results provide an interesting insight into suitable methods to employ when teaching technical subjects to a cohort having differing background skill levels. 相似文献
10.
Spatial cloud computing: how can the geospatial sciences use and help shape cloud computing? 总被引：1，自引：0，他引：1
《International Journal of Digital Earth》2013,6(4):305-329
Abstract The geospatial sciences face grand information technology (IT) challenges in the twenty-first century: data intensity, computing intensity, concurrent access intensity and spatiotemporal intensity. These challenges require the readiness of a computing infrastructure that can: (1) better support discovery, access and utilization of data and data processing so as to relieve scientists and engineers of IT tasks and focus on scientific discoveries; (2) provide real-time IT resources to enable real-time applications, such as emergency response; (3) deal with access spikes; and (4) provide more reliable and scalable service for massive numbers of concurrent users to advance public knowledge. The emergence of cloud computing provides a potential solution with an elastic, on-demand computing platform to integrate – observation systems, parameter extracting algorithms, phenomena simulations, analytical visualization and decision support, and to provide social impact and user feedback – the essential elements of the geospatial sciences. We discuss the utilization of cloud computing to support the intensities of geospatial sciences by reporting from our investigations on how cloud computing could enable the geospatial sciences and how spatiotemporal principles, the kernel of the geospatial sciences, could be utilized to ensure the benefits of cloud computing. Four research examples are presented to analyze how to: (1) search, access and utilize geospatial data; (2) configure computing infrastructure to enable the computability of intensive simulation models; (3) disseminate and utilize research results for massive numbers of concurrent users; and (4) adopt spatiotemporal principles to support spatiotemporal intensive applications. The paper concludes with a discussion of opportunities and challenges for spatial cloud computing (SCC). 相似文献
11.
The COVID-19(coronavirus)disease has affected over 100 countries in a matter of weeks.The way humans live and work on planet Earth has changed profoundly over the last months.Many lives and livelihoods have been lost.Ways of working,shopping,and social interactions are all vastly different for most of us.We do not know when the current crisis will end,or how far we will"return"to the way things were before the pandemic.The world is experiencing one of the most transformative moments of the last 100 years.The social,economic,and political influences of the COVID-19 crisis have already been hugely momentous,we do not utterly understand it.Looking ahead,we have inevitably had to make important public health,economic,governance,and ecological decisions with less information than usual and to reverse recently adopted policies,which can lead to an era of disruptive transformations to sustainability.During these historic times,we must understand the hidden reality of the earth system and attempt to transform our needs so that we all have a sustained future on our planet. 相似文献
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In geographic information science, a plethora of different approaches and methods is used to assess the similarity of movement. Some of these approaches term two moving objects similar if they share akin paths. Others require objects to move at similar speed and yet others consider movement similar if it occurs at the same time. We believe that a structured and comprehensive classification of movement comparison measures is missing. We argue that such a classification not only depicts the status quo of qualitative and quantitative movement analysis, but also allows for identifying those aspects of movement for which similarity measures are scarce or entirely missing.In this review paper we, first, decompose movement into its spatial, temporal, and spatiotemporal movement parameters. A movement parameter is a physical quantity of movement, such as speed, spatial path, or temporal duration. For each of these parameters we then review qualitative and quantitative methods of how to compare movement. Thus, we provide a systematic and comprehensive classification of different movement similarity measures used in geographic information science. This classification is a valuable first step toward a GIS toolbox comprising all relevant movement comparison methods. 相似文献
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Andrew U. Frank 《Journal of Geographical Systems》2000,2(1):99-105
Geographical Information Science is essentially computational geography and has its own research program, namely all aspects
of formal models for spatial natural processes and the interaction of humans with the environment in space and time. This
is not a question of technology and technology-related research; but technology influences what questions can be researched
effectively. Collection of data in the field and the simulation of field experience through Virtual Reality are just two questions
of how spatial reality and human experience are linked. The focus on human spatial cognition is similarly found in software
engineering for interoperable Geographic Information Systems. 相似文献
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Jeffrey D. Hamerlinck 《制图学和地理信息科学》2015,42(4):11-17
Popular and professional interest in maps and map-making has never been greater. Despite this engagement, introductory skills courses in “map use” have largely disappeared in undergraduate geography and cartography programs at US universities, with research indicating that both map-use course enrollments and the existence of such courses themselves are on the decline. While the map-use course and its content may have been replaced by, repackaged as, or incorporated into an integrated geographical information systems-cartography–remote sensing foundations course, how do we ensure that an understanding of maps and their unique characteristics is not lost in the mix? This essay describes a recent course redesign experience incorporating information literacy, technology fluency, and spatial thinking principles to maintain map-use concepts, skills, and appreciation in an introductory geographic information science and technology (GIS&T) foundations course, meeting both GIS&T and general education curricular goals. 相似文献
20.
CHENGPenggen SHIWenzhong GONGJianya ZHOUGuoqing 《地球空间信息科学学报》2005,8(1):64-71
3D spatial data model and simulating are the core of 3D GIS can be adopted in different domains. A data model based on Quasi Tri-Prism Volume (QTPV) has been proposed. QTPV definition and its special cases have been discussed. Using QTPV and its special cases, irregular natural geological bodies and regular subsurface engineering can be described efficiently. The proposed model is composed of five primitives and six objects. Data structures and topological relationship of the fives primitives and three objects describing stratigraphy are designed in detail Some schemes are designed for the QTPV modelling of stratigraphy and subsurface engineering according to modelling data. The model manipulation method of QTPV cutting by an arbitrary plane is discussed. Using VC 6.0 programming language integrated with SQL database and OpenGL graphic library under windows environment, a system prototype 3DGeoMV has been developed. The experiment result shows that the QTPV model is feasible and efficient in modelling subsurface engineering. 相似文献