Interoperable data exchange and reproducibility are increasingly important for modern scientific research. This paper shows how three open source projects work together to realize this: (i) the R project, providing th...
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ISBN:
(纸本)9783642197895
Interoperable data exchange and reproducibility are increasingly important for modern scientific research. This paper shows how three open source projects work together to realize this: (i) the R project, providing the lingua franca for statistical analysis, (ii) the Open Geospatial Consortium's Sensor Observation Service (SOS), a standardized data warehouse service for storing and retrieving sensor measurements, and (iii) sos4R, a new project that connects the former two. We show how sos4R can bridge the gap between two communities in science: spatial statistical analysis and visualization on one side and the Sensor Web community on the other. sos4R enables R users to integrate (near real-time) sensor observations directly into R. Finally, we evaluate the functionality of sos4R. The software encapsulates the service's complexity with typical R function calls in a common analysis workflow, but still gives users full flexibility to handle interoperability issues. We conclude that it is able to close the gap between R and the sensor web.
The number of Sensor Observation Service (SOS) instances available online has been increasing in the last few years. The SOS specification standardises interfaces and data formats for exchanging sensor-related informa...
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ISBN:
(纸本)9783642197895
The number of Sensor Observation Service (SOS) instances available online has been increasing in the last few years. The SOS specification standardises interfaces and data formats for exchanging sensor-related information between information providers and consumers. SOS, in conjunction with other specifications in the Sensor Web Enablement initiative, attempts to realise the Sensor Web vision, a worldwide system where sensor networks of any kind are interconnected. In this paper, we present an empirical study of actual instances of servers implementing SOS. The study focuses mostly in which parts of the specification are more frequently included in real implementations and how exchanged messages follow the structure defined by XML Schema files. Our findings can be of practical use when implementing servers and clients based on the SOS specification, as they can be optimized for common scenarios.
The paper presents a scalable approach for generalization of large land-cover data sets using partitioning in a spatial database and fast generalization algorithms. In the partitioning step, the data set is split into...
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ISBN:
(纸本)9783642197895
The paper presents a scalable approach for generalization of large land-cover data sets using partitioning in a spatial database and fast generalization algorithms. In the partitioning step, the data set is split into rectangular overlapping tiles. These are processed independently and then composed into one result. For each tile, semantic and geometric generalization operations are performed to remove features that are too small from the data set. The generalization approach is composed of several steps consisting of topologic cleaning, aggregation, feature partitioning, identification of mixed feature classes to form heterogeneous classes, and simplification of feature outlines. The workflow will be presented with examples for generating CORINE Land Cover (CLC) features from the high resolution German authoritative land-cover data set of the whole area of Germany (DLM-DE). The results will be discussed in detail, including runtimes as well as dependency of the result on the parameter setting.
The goal of this research is to develop a 3D topological structure to represent a 3D space partition with validation functionality and support for conversions from topological to geometrical primitives. Several 3D top...
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ISBN:
(纸本)9783642197895
The goal of this research is to develop a 3D topological structure to represent a 3D space partition with validation functionality and support for conversions from topological to geometrical primitives. Several 3D topological structures have been presented in the past, mainly by researchers. The technical (implementation) model developed in this paper is based on the conceptual model of the ISO 19107 'spatial schema' standard and consists of four topological primitives: node, edge, face, and volume, which are related to each other via their (co)boundary relationships. In our setting, only linear primitives (no curves) are supported and no isolated and dangling primitives are allowed. In our model, the rings, the shells, and the orientation play key roles within the topological structure and the functions that implement the geometrical realization. There was no formal definition of a valid 3D topological structure available and this paper presents such a definition, which is the main novel contribution. This definition is presented in three levels, where at every next level the definition is further refined such that finally a set of rules is proposed, which can be implemented unambiguously. In order to validate a 3D topological structure, the involved volumes must be valid as well as the whole structure, which means the relationships between the volumes. The rules for a valid structure have been implemented on top of Oracle Spatial and tested with artificial and real-world test data.
Iran is one of the most seismically active regions of the globe. The metropolis of Tehran is located at the southern foothills of the Alborz Mountains that are the northern branch of the Alpine-Himalayan orogeny in Ir...
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ISBN:
(纸本)9783642197895
Iran is one of the most seismically active regions of the globe. The metropolis of Tehran is located at the southern foothills of the Alborz Mountains that are the northern branch of the Alpine-Himalayan orogeny in Iran. The extremely high density of population concentrated in the Tehran metropolis (with more than 12 million inhabitants) coupled with the fragility of houses and life-lines, highlight the urgency of a reliable assessment of fault activity in this city. Three main active fault zones exist in the vicinity of Tehran: North Tehran fault;Mosha fault;and Eyvanekey-Kahrizak fault. In this paper, a total of 894 historical earthquakes of the study area with magnitudes over 2.5 Richter were collected since 1900. Three scenarios were considered for faults. In each scenario, every earthquake was associated to its relevant fault, spatial and temporal analyses were done to reveal the spatial and temporal trend of fault activities. First the north-south and east-west trends of magnitudes of earthquakes were verified and showed no meaningful trends. Spatial dependence of magnitudes of earthquakes was described in terms of global Moran's I and general G. The indices showed that the magnitudes of earthquakes were not clustered or spatially correlated. Ripley's K function determined that earthquakes are clustered at multiple distances. The temporal analyses were used to extract temporal trends in each scenario. The results showed that eastern sections of all faults are more active and the majority of large earthquakes have occurred in the middle sections of the faults. It is also anticipated that the eastern section of the Mosha fault is more capable of generating large earthquakes than the other faults in the Tehran region. The results of this paper can be useful for extracting hazardous areas and risk zonation or forecasting earthquakes.
The Workshop Proceedings reflect problems of advanced geo-information science as far as they are specifically concerned with the maritime environment at large. The Proceedings incorporate papers presented by leading s...
ISBN:
(数字)9783642197666
ISBN:
(纸本)3642197655;9783642197659
The Workshop Proceedings reflect problems of advanced geo-information science as far as they are specifically concerned with the maritime environment at large. The Proceedings incorporate papers presented by leading scientists researching in the considered professional area and by practitioners engaged in GIS and GIS applications development. They pay close attention to the problems of scientific and technological innovations and the ensuing opportunities to make seas safer and cleaner. Furthermore, they periodically measure the ground covered and new challenges with respect to economic and shipping trends as related to Artificial Intelligence; GIS ontologies; GIS data integration and modelling; Underwater acoustics; GIS data fusion; GIS and corporate information systems; GIS and real-time monitoring systems; GIS algorithms and computational issues; Novel and emerging marine GIS research areas; Monitoring of maritime terrorist threat; Maritime and environmental GIS; Navigation-based and maritime transportation GIS; Human factors in maritime GIS; Coastal and environmental GIS.
The OpenGIS Catalogue Services (CS) specification defines a set of abstract interfaces for the discovery, access, maintenance and organization of metadata repositories of geospatial information and related resources i...
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ISBN:
(纸本)9783642123252
The OpenGIS Catalogue Services (CS) specification defines a set of abstract interfaces for the discovery, access, maintenance and organization of metadata repositories of geospatial information and related resources in distributed computing scenarios, such as the Web. The CS specification also defines a HTTP protocol binding, which is called "Catalogue Services for the Web" or CSW. A fair description of CSW is a remote catalogue interface over the HTTP protocol, but not over the architecture of the mainstream Web where search engines are the users' gateway to information. This paper identifies some aspects of CSW that difficult the findability of metadata in the Web, and hence, the discovery of resources. This paper also presents a toolkit that exposes as Linked Data the content of metadata repositories offered through CSW with the purpose of improving the discovery of metadata records in search engines.
作者：
Weber, PatrickChapman, DaveUCL
Dept Comp Sci Gower St London WC1E 6BT England UCL
Dept Management Sci & Innovat London WC1E 6BT England
This paper discusses the methodology and processes required to implement a geo-business classification to aid spatial decision making in the context of foreign direct investment promotion for London. This research is ...
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ISBN:
(纸本)9783642123252
This paper discusses the methodology and processes required to implement a geo-business classification to aid spatial decision making in the context of foreign direct investment promotion for London. This research is both timely and relevant since there is need for better decision support tools that will improve sub-regional location decision making ensuring London's diverse business neighbourhoods are presented effectively to potential investors. The research methodology presented in this paper adopts principals and practices common place in consumer marketing in the form of geodemographic classification. The five key data domains associated with companies, working property stock, general living environment and accessibility were used to gather a range of input variables. These variables were then used as the input to a principal components analysis which simplified the data into 9 dimensions describing and contrasting London's diverse business neighbourhoods. These geo-business area profiles will form the basis for spatial decision support tools for business location decision making.
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