Página 1 dos resultados de 619 itens digitais encontrados em 0.009 segundos

Management of integrity constraints for multi-scale geospatial data = : Gerenciamento de restrições de integridade para dados geoespaciais multi-escala; Gerenciamento de restrições de integridade para dados geoespaciais multi-escala

João Sávio Ceregatti Longo
Fonte: Biblioteca Digital da Unicamp Publicador: Biblioteca Digital da Unicamp
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 13/03/2013 Português
Relevância na Pesquisa
57.399873%
Trabalhar em questões relativas a dados geoespaciais presentes em múltiplas escalas apresenta inúmeros desafios que têm sido atacados pelos pesquisadores da área de GIS (Sistemas de Informação Geográfica). De fato, um dado problema do mundo real deve frequentemente ser estudado em escalas distintas para ser resolvido. Outro fator a ser considerado é a possibilidade de manter o histórico de mudanças em cada escala. Além disso, uma das principais metas de ambientes multi-escala _e garantir a manipulação de informações sem qualquer contradição entre suas diferentes representações. A noção de escala extrapola inclusive a questão espacial, pois se aplica também, por exemplo, _a escala temporal. Estes problemas serão analisados nesta dissertação, resultando nas seguintes contribuições: (a) proposta do modelo DBV (Database Version) multi-escala para gerenciar de forma transparente dados de múltiplas escalas sob a perspectiva de bancos de dados; (b) especificação de restrições de integridade multi-escala; (c) implementação de uma plataforma que suporte o modelo e as restrições, testados com dados reais multi-escala.; Work on multi-scale issues concerning geospatial data presents countless challenges that have been long attacked by GIScience (Geographic Information Science) researchers. Indeed...

An OGC/SOS conformant client to manage geospatial data on the GRID

Esteves, António; Caldas, Marco; Pina, António Manuel Silva; Proença, Alberto José
Fonte: Netbiblo Publicador: Netbiblo
Tipo: Artigo de Revista Científica
Publicado em //2010 Português
Relevância na Pesquisa
67.8334%
This paper describes a Sensor Observation Service (SOS) client developed to integrate dynamic geospatial data from meteorological sensors, on a grid-based risk management decision support system. The present work is part of the CROSS-Fire project, which uses forest fires as the main case study and the FireStation application to simulate fire spread. The meteorological data is accessed through the SOS standard from Open Geospatial Consortium (OGC), using the Observations and Measurements (O&M) standard encoding format. Since the SOS standard was not designed to directly access sensors, we developed an interface application to load the SOS database with observations from a Vantis Weather Station (WS). To integrate the SOS meteorological data into the FireStation, the developed SOS client was embedded on a Web Processing Service (WPS) algorithm. This algorithm was designed to be functional and fully compliant with SOS, SensorML, and O&M standards from OGC. With minor modifications to the developed SOS database interface, the SOS client works with any WS. This client supports spatial and temporal filters, including the integration of dynamic data from satellites into FireStation, as described.; Fundação para a Ciência e a Tecnologia (FCT)

Spatial data infrastructures model for developing countries: A case study of Nigeria

Onah, Chinonye Cletus
Fonte: Universidade Nova de Lisboa Publicador: Universidade Nova de Lisboa
Tipo: Dissertação de Mestrado
Publicado em 05/03/2009 Português
Relevância na Pesquisa
57.655674%
Dissertation submitted in partial fulfilment of the requirements for the Degree of Master of Science in Geospatial Technologies; This research explores the basics of SDI, and investigates the National SDI of different countries. Further, the research analyses SDI implementation in developing country with specific reference to the National Geospatial Data Infrastructure (NGDI) of Nigeria. The research assesses the status and the milestones of NGDI implementation using key SDI components as assessment variables. These components were grouped into four classes: Policy and Legal Issues, Technical, Funding and People. A questionnaire survey via email was conducted on the stakeholders and users of geoinformation in Nigeria. From the analysis, the NGDI has an advantage of having a national policy backing its implementation and the establishment of the coordinating body. However, the lack of SDI directive and funding are major hurdles in the implementation of the NGDI making it lack behind most of the selected case study countries in other key components. Nigeria is also found to be applying a Mixed Model of NSDI implementation as both product model and process model are evident in the NGDI. In the real sense of access network and data sharing...

Exploratory geospatial data analysis using self-organizing maps

Lourenço, Fernando Correia
Fonte: Universidade Nova de Lisboa Publicador: Universidade Nova de Lisboa
Tipo: Dissertação de Mestrado
Publicado em 15/07/2005 Português
Relevância na Pesquisa
57.46515%
Dissertação apresentada como requisito parcial para obtenção do grau de Mestre em Ciência e Sistemas de Informação Geográfica; The rapidly increasing volume of digital geographic data is overwhelming for conventional analysis techniques and methods. Therefore new approaches are needed to transform data into information, and ultimately, into knowledge. Exploratory data analysis is a foundation stone in this process. It is concerned with the formation of a simplified overview of data sets. Clustering and projection are among the examples of useful methods to achieve this task. The Self-Organizing Map (SOM) algorithm performs both, in a non-linear mapping from a high-dimensional data space to a low-dimensional space aiming to preserve the topological relations in the data. The aim of this thesis is to demonstrate the effectiveness of SOM application in visual exploration of physical geography data to support the delineation of Portuguese mainland regions. The main justifications for the application of SOM in this issue are its features of stressing local factors and topological ordering. For experimental assessment, the public domain thematic maps from Instituto do Ambiente are used. Several authors’ maps of Portuguese regions are used for evaluation of empirical results.(...)

Geospatial data harmonization from regional level to european level: a usa case in forest fire data

Otsu, Kaori
Fonte: Universidade Nova de Lisboa Publicador: Universidade Nova de Lisboa
Tipo: Dissertação de Mestrado
Publicado em 04/03/2010 Português
Relevância na Pesquisa
68.00999%
Dissertation submitted in partial fulfillment of the requirements for the Degree of Master of Science in Geospatial Technologies.; Geospatial data harmonization is becoming more and more important to increase interoperability of heterogeneous data derived from various sources in spatial data infrastructures. To address this harmonization issue we present the current status of data availability among different communities, languages, and administrative scales from regional to national and European levels. With a use case in forest data models in Europe, interoperability of burned area data derived from Europe and Valencia Community in Spain were tested and analyzed on the syntactic, schematic and semantic level. We suggest approaches for achieving a higher chance of data interoperability to guide forest domain experts in forest fire analysis. For testing syntactic interoperability, a common platform in the context of formats and web services was examined. We found that establishing OGC standard web services in a combination with GIS software applications that support various formats and web services can increase the chance of achieving syntactic interoperability between multiple geospatial data derived from different sources. For testing schematic and semantic interoperability...

Public private collaboration: Potentials for spatial data infrastructure development in developing countries - A caste study of Nigeria

Nkwor, Chima Ogbonnaya
Fonte: Universidade Nova de Lisboa Publicador: Universidade Nova de Lisboa
Tipo: Dissertação de Mestrado
Publicado em 07/02/2011 Português
Relevância na Pesquisa
47.74346%
Dissertation submitted in partial fulfillment of the requirements for the Degree of Master of Science in Geospatial Technologies.; Many countries across the world embark on the building of SDI to facilitate the sustainable development of their country. However the challenge of developing such infrastructure to a large extent depends on its implementation, which is significant that no single sector can address alone without collaboration and partnership. Public Private Partnership (PPP) is among the strategies currently adovated for SDI development by various SDI experts. This research therefore analyzes SDI development with reference to the institutional arrangements, policy and technology components of SDI and PPP case experiences of Australia, Canada, United States and the Netherlands from developed countries and on the other hand, Egypt and South Africa from the developing countries. A questionnaire survey and literature review was carried out on relevant GI organizations to ascertain the status of the NGDI development and the potentials of PPP in the geospatial sector in Nigeria. The analysis reveals that PPP has a high level of acceptance among respondents as an approach in the future for the development of SDI in Nigeria. However...

A standards-based framework to foster geospatial data and process interoperability

Pastorello Jr,Gilberto Zonta; Senra,Rodrigo Dias Arruda; Medeiros,Claudia Bauzer
Fonte: Sociedade Brasileira de Computação Publicador: Sociedade Brasileira de Computação
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/03/2009 Português
Relevância na Pesquisa
57.99675%
The quest for interoperability is one of the main driving forces behind international organizations such as OGC and W3C. In parallel, a trend in systems design and development is to break down GIS functionalities into modules that can be composed in an ad hoc manner. This component-driven approach increases flexibility and extensibility. For scientists whose research involves geospatial analysis, however, such initiatives mean more than interoperability and flexibility. These efforts are progressively shielding these users from having to deal with problems such as data representation formats, communication protocols or pre-processing algorithms. Once scientists are allowed to abstract from lower level concerns, they can shift their focus to the design and implementation of the computational models they are interested in. This paper analyzes how interoperability and componentization efforts have this underestimated impact on the design and development perspective. This discussion is illustrated by the description of the design and implementation of WebMAPS, a geospatial information system to support agricultural planning and monitoring. By taking advantage of new results in the above areas, the experience with WebMAPS presents a road map to leverage system design and development by the seamless composition of distributed data sources and processing solutions.

Geospatial metadata retrieval from web services

Barbosa,Ivanildo
Fonte: Universidade Federal do Paraná Publicador: Universidade Federal do Paraná
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/03/2013 Português
Relevância na Pesquisa
47.74346%
Nowadays, producers of geospatial data in either raster or vector formats are able to make them available on the World Wide Web by deploying web services that enable users to access and query on those contents even without specific software for geoprocessing. Several providers around the world have deployed instances of WMS (Web Map Service), WFS (Web Feature Service) and WCS (Web Coverage Service), all of them specified by the Open Geospatial Consortium (OGC). In consequence, metadata about the available contents can be retrieved to be compared with similar offline datasets from other sources. This paper presents a brief summary and describes the matching process between the specifications for OGC web services (WMS, WFS and WCS) and the specifications for metadata required by the ISO 19115 - adopted as reference for several national metadata profiles, including the Brazilian one. This process focuses on retrieving metadata about the identification and data quality packages as well as indicates the directions to retrieve metadata related to other packages. Therefore, users are able to assess whether the provided contents fit to their purposes.

From intervals to domains: towards a general description of validated uncertainty, with potential applications to geospatial and meteorological data

Kreinovich, Vladik; Kosheleva, Olga; Starks, Scott Allen; Tupelly, Kavitha; Dimuro, Graçaliz Pereira; Costa, Antônio Carlos da Rocha; Villaverde, Karen
Fonte: Universidade Federal do Rio Grande Publicador: Universidade Federal do Rio Grande
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
47.62756%
When physical quantities xi are numbers, then the corresponding measurement accuracy can be usually represented in interval terms, and interval computations can be used to estimate the resulting uncertainty in y = f (x1,...,xn). In some practical problems, we are interested in more complex structures such as functions, operators, etc. Examples: we may be interested in how the material strain depends on the applied stress, or in how a physical quantity such as temperature or velocity of sound depends on a 3-D point. For many such structures, there are ways to represent uncertainty, but usually, for each new structure, we have to perform a lot of complex analysis from scratch. It is desirable to come up with a general methodology that would automatically produce a natural description of validated uncertainty for all physically interesting situations (or at least for as many such situations as possible). In this paper, we describe the foundations for such a methodology; it turns out that this problem naturally leads to the technique of domains first introduced by D. Scott in the 1970s. In addition to general domain techniques, we also describe applications to geospatial and meteorological data.

Geospatial Data Indexing Analysis and Visualization via Web Services with Autonomic Resource Management

Lu, Yun
Fonte: FIU Digital Commons Publicador: FIU Digital Commons
Tipo: Artigo de Revista Científica Formato: application/pdf
Português
Relevância na Pesquisa
47.70336%
With the exponential growth of the usage of web-based map services, the web GIS application has become more and more popular. Spatial data index, search, analysis, visualization and the resource management of such services are becoming increasingly important to deliver user-desired Quality of Service. First, spatial indexing is typically time-consuming and is not available to end-users. To address this, we introduce TerraFly sksOpen, an open-sourced an Online Indexing and Querying System for Big Geospatial Data. Integrated with the TerraFly Geospatial database [1-9], sksOpen is an efficient indexing and query engine for processing Top-k Spatial Boolean Queries. Further, we provide ergonomic visualization of query results on interactive maps to facilitate the user’s data analysis. Second, due to the highly complex and dynamic nature of GIS systems, it is quite challenging for the end users to quickly understand and analyze the spatial data, and to efficiently share their own data and analysis results with others. Built on the TerraFly Geo spatial database, TerraFly GeoCloud is an extra layer running upon the TerraFly map and can efficiently support many different visualization functions and spatial data analysis models. Furthermore...

Delineation of the geospatial dimensions of the residential real estate submarket structure.

Lockwood, Anthony J. M.
Fonte: Universidade de Adelaide Publicador: Universidade de Adelaide
Tipo: Tese de Doutorado
Publicado em //2008 Português
Relevância na Pesquisa
47.917896%
While it is generally accepted that residential submarkets exist, this is not the case for either their definition or delineation. This study has developed and assessed a methodology for deriving the geospatial dimensions of residential real estate submarkets based on the behaviour of the marketplace with respect to the underlying dimensions of the residential real estate living structure (RLS). Importantly, the methodology makes no prior assumptions about where the spatial boundaries might be. They were empirically derived from the data alone. It is achieved by building on previous work in the field and seeking to identify the fundamental issues in residential real estate market behaviour. The first basic premise of the thesis is that when a dwelling is sold, the commodity traded is a piece of real estate geography comprising a complex bundle of both spatial and structural attributes. The second basic premise is the recognition in the methodology of the importance of ‘location’. The price of the real estate geography varies across geographical space in a continuous fashion and it is this price variability that is defined, in this study, to be the geospatial submarket identifier. The study adopts a two-stage methodology reflecting these two basic premises. Firstly...

Distributed Geospatial Data Processing Functionality to Support Collaborative and Rapid Emergency Response

BRUNNER Dominik; LEMOINE Guido; THOORENS Francois-Xavier; BRUZZONE Lorenzo
Fonte: IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC Publicador: IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC
Tipo: Articles in Journals Formato: Printed
Português
Relevância na Pesquisa
47.78497%
This paper presents a novel approach to integrate the latest generation very high-resolution earth observation imagery into the operational workflow of geospatial information support for emergency response actions. The core concept behind this approach is the implementation of an image pyramid structure that allows each image tile to be addressed separately.We propose a novel way to collate geospatial feature data from distributed sources and integrate them in visualization and image processing. The system components enable rapid collaborative mapping, support for in situ data collection, customized on-demand image processing, and geospatial data queries and near instantaneous map visualization. We adapt functional software modules that are available in the public and open source domain. The approach is demonstrated with a test case in a rapid damage assessment scenario using very high-resolution optical satellite QuickBird and IKONOS imagery over Southern Lebanon from 2006.; JRC.G.2-Global security and crisis management

Ontology-Driven Translation of Geospatial Data

SCHADE SVEN
Fonte: AKA - Akademische Verlagsgesellschaft AKA GmbH Publicador: AKA - Akademische Verlagsgesellschaft AKA GmbH
Tipo: PhD Theses Formato: Printed
Português
Relevância na Pesquisa
47.89547%
Current methods for specifying data models lack well-defined descriptions of the expressions, which represent data types, attributes, attribute values, and operations. It is impossible to define clear translation rules for data models, because the relation between source and target data model elements is not computable. Furthermore, translation has to account for imprecision caused by conceptual heterogeneities and measurement error. In this thesis we use the DOLCE foundational ontology to provide a semantic reference frame for geospatial data. Available extensions to DOLCE are profiled and additional geospatial characteristics, such as topological relations are included. Annotating (or semantically referencing) expressions, which are used to define geospatial data models, with this frame supports computability and allows for selecting appropriate translation rules on the attribute level. Using a logic-based approach, semantically referenced data models allow for inferring relations between source and target attributes. This includes inference on applicable translation operations and the detection of match types (exact, upper bound, and lower bound) between attributes. If detected match types fit the user¿s purpose, translation scripts are extracted. The scripts are executed using an algebraic theory...

Exporting Geospatial Data to Web Tiled Map Services using GRASS GIS

CEBECAUER Tomas; SURI MARCEL
Fonte: OSGeo Foundation Publicador: OSGeo Foundation
Tipo: Articles in periodicals and books Formato: Printed
Português
Relevância na Pesquisa
47.655674%
We present a method for exporting raster-based geospatial data to the web environment of the Tiled Map Services with special focus on Google Maps and Microsoft Virtual Earth. The method has been implemented in the open source GRASS GIS software and it includes the exact re-projection of raster data, their tiling, and export to the hierarchical structure of PNG graphical files. The approach is based on the adaptation of projection parameters of the standard PROJ4 library and implementation of the technical specifications and tiling scheme of the services. The developed program has been used to integrate high-resolution raster data with Google Maps Application Programming Interface in the web portal PVGIS which offers geospatial data and tools to the solar energy sector.; JRC.F.7-Renewable Energy

Integration of X3D Geospatial in a Data Driven Web Application

McCann, Michael; Yoo, Byounghyun; Brutzman, Don
Fonte: Escola de Pós-Graduação Naval Publicador: Escola de Pós-Graduação Naval
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
47.78497%
The Monterey Bay Aquarium Research Institute designed the Spatial Temporal Oceanographic Query System (STOQS) [MBARI 2014] to create new capabilities for scientists to gain insight from their data. STOQS employs open standards and is a 100% free and open source project. It includes a web-based graphical user interface where X3D Geospatial has been integrated to enable 3D geospatial data visualization.

Annotating data to support decision-making: a case study.

MACARIO, C. G. N.; SANTOS, J. A. dos; MEDEIROS, C. B.; TORRES, R. da S.
Fonte: In: WORKSHOP ON GEOGRAPHIC INFORMATION RETRIEVAL, 6, 2010, Zurich. Proceedings... New York: ACM, 2010. Publicador: In: WORKSHOP ON GEOGRAPHIC INFORMATION RETRIEVAL, 6, 2010, Zurich. Proceedings... New York: ACM, 2010.
Tipo: Artigo em anais de congresso (ALICE) Formato: Não paginado.
Português
Relevância na Pesquisa
57.72095%
Georeferenced data are a key factor in many decision-making systems. However, their interpretation is user and context dependent so that, for each situation, data analysts have to interpret them, a time-consuming task. One approach to alleviate this task, is the use of semantic annotations to store the produced information. Annotating data is however hard to perform and prone to errors, especially when executed manually. This difficulty increases with the amount of data to annotate. Moreover, annotation requires multidisciplinary collaboration of researchers, with access to heterogeneous and distributed data sources and scientific computations. This paper illustrates our solution to approach this problem by means of a case study in agriculture. It shows how our implementation of a framework to automate the annotation of geospatial data can be used to process real data from remote sensing images and other official Brazilian data sources.; 2010; GIR'10.

Geospatial Big Data Handling Theory and Methods: A Review and Research Challenges

Li, S.; Dragicevic, S.; Anton, F.; Sester, M.; Winter, S.; Coltekin, A.; Pettit, C.; Jiang, B.; Haworth, J.; Stein, A.; Cheng, T.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 10/11/2015 Português
Relevância na Pesquisa
48.074287%
Big data has now become a strong focus of global interest that is increasingly attracting the attention of academia, industry, government and other organizations. Big data can be situated in the disciplinary area of traditional geospatial data handling theory and methods. The increasing volume and varying format of collected geospatial big data presents challenges in storing, managing, processing, analyzing, visualizing and verifying the quality of data. This has implications for the quality of decisions made with big data. Consequently, this position paper of the International Society for Photogrammetry and Remote Sensing (ISPRS) Technical Commission II (TC II) revisits the existing geospatial data handling methods and theories to determine if they are still capable of handling emerging geospatial big data. Further, the paper synthesises problems, major issues and challenges with current developments as well as recommending what needs to be developed further in the near future. Keywords: Big data, Geospatial, Data handling, Analytics, Spatial Modeling, Review; Comment: 25 pages, 3 figures

Curation and preservation of complex data: North Carolina Geospatial Data Archiving Project

Morris, S; Tuttle, J
Fonte: Universidade Duke Publicador: Universidade Duke
Tipo: Conference Proceeding Formato: 1 - 9 (9)
Publicado em // Português
Relevância na Pesquisa
57.99727%
The North Carolina Geospatial Data Archiving Project (NCGDAP) is a three-year joint effort of the North Carolina State University Libraries and the North Carolina Center for Geographic Information and Analysis focused on collection and preservation of digital geospatial data resources from state and local government agencies. NCGDAP is being undertaken in partnership with the Library of Congress under the National Digital Information Infrastructure and Preservation Program (NDIIPP). “Digital geospatial data” consists of digital information that identifies the geographic location and characteristics of natural or constructed features and boundaries on the earth. Such data resources include geographic information systems (GIS) data sets, digitized maps, remote sensing data resources such as digital aerial photography, and tabular data that are tied to specific locations. These complex data objects do not suffer well from neglect, and long-term preservation will involve some combination of format migration and retention of critical documentation. While the main focus of NCGDAP is on organizational issues related to the engagement of spatial data infrastructure in the process of data archiving--with the demonstration repository seen more as a catalyst for discussion rather than an end in itself--this paper focuses more narrowly on the technical challenges associated with developing an ingest workflow and archive development process. New preservation challenges associated with emergent content forms are also presented.

Curation and preservation of complex data: North Carolina Geospatial Data Archiving Project

Tuttle, J; Morris, S
Fonte: Universidade Duke Publicador: Universidade Duke
Tipo: Conference Proceeding
Publicado em // Português
Relevância na Pesquisa
68.00631%
The North Carolina Geospatial Data Archiving Project (NCGDAP) is a three-year joint effort of the North Carolina State University Libraries and the North Carolina Center for Geographic Information and Analysis focused on collection and preservation of digital geospatial data resources from state and local government agencies. CGDAP is being undertaken in partnership with the Library of Congress under the ational Digital Information Infrastructure and Preservation Program (NDIIPP). “Digital geospatial data” consists of digital information that identifies the geographic location and characteristics of natural or constructed features and boundaries on the earth. Such data resources include geographic information systems (GIS) data sets, digitized maps, remote sensing data resources such as digital aerial photography, and tabular data that are tied to specific locations. These complex data objects do not suffer well from neglect, and long-term preservation will involve some combination of format migration and retention of critical documentation. While the main focus of NCGDAP is on organizational issues related to the engagement of spatial data infrastructure in the process of data archiving--with the demonstration repository seen more as a catalyst for discussion rather than an end in itself--this paper focuses more narrowly on the technical challenges associated with eveloping an ingest workflow and archive development process. New preservation hallenges associated with emergent content forms are also resented.

SEMANTIC DESCRIPTION FOR THE TAXONOMY OF THE GEOSPATIAL SERVICES

Li, Hao; UFPR; Wang, Yandong; State Key Laboratory of Information Engineering in Surveying, Mapping and Remote Sensing, Wuhan University, Wuhan, Hubei, China; Cheng, Penggen; Faculty of Geomatics, East China Institute of Technology, Nanchang, Jiangxi, Chi
Fonte: Universidade Federal do Paraná-UFPR Publicador: Universidade Federal do Paraná-UFPR
Tipo: info:eu-repo/semantics/article; info:eu-repo/semantics/publishedVersion; Artigo Avaliado pelos Pares Formato: application/pdf
Publicado em 24/09/2015 Português
Relevância na Pesquisa
47.92658%
With the advances in the World Wide Web and Geographic Information System, geospatial services have progressively developed to provide geospatial data and processing functions online. In order to efficiently discover and manage the large amount of geospatial services, these services are registered with semantic descriptions and categorized into classes according to certain taxonomies. Most taxonomies for geospatial services are only provided in the human readable format. The lack of semantic description for taxonomies limits the semantic-based discovery of geospatial services. The objectives of this paper are proposing an approach to semantically describe the taxonomy of geospatial services and using the semantic descriptions for taxonomy to improve the discovery of geospatial services. A semantic description framework is introduced for geospatial service taxonomy to describe not only the hierarchical structure of classes but also the definitions for all classes. The semantic description of taxonomy base on this framework is further used to simplify the semantic description and registration of geospatial services and enhance the semantic-based service matching method.