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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Prise en compte des dépendances entre données thématiques utilisateur et données topographiques lors d’un changement de niveau de détail / Taking into account the dependences between user thematic data and topographic data when the level of detail is changed

Jaara, Kusay 10 March 2015 (has links)
Avec l'importante disponibilité de données topographiques de référence, la création des données géographiques n'est plus réservée aux professionnels de l'information géographique. De plus en plus d'utilisateurs saisissent leurs propres données, que nous appelons données thématiques, en s'appuyant sur ces données de référence qui jouent alors le rôle de données support. Les données thématiques ainsi saisies font sens en tant que telles, mais surtout de par leurs relations avec les données topographiques. La non prise en compte des relations entre données thématiques et topographiques lors de traitements modifiant les unes ou les autres peut engendrer des incohérences, notamment pour les traitements liés au changement de niveau de détail. L'objectif de la thèse est de définir une méthodologie pour préserver la cohérence entre les données thématiques et topographiques lors d'un changement de niveau de détail. Nous nous concentrons sur l'adaptation des données thématiques suite à une modification des données topographiques, processus que nous appelons migration des données thématiques. Nous proposons d'abord un modèle pour la migration de données thématiques ponctuelles sur réseau composé de : (1) un modèle pour décrire le référencement des données thématiques sur les données topographiques par des relations spatiales (2) une méthode de relocalisation basée sur ces relations. L'approche consiste à identifier les relations finales attendues en fonction des relations initiales et des changements sur les données topographiques entre les états initial et final. La relocalisation est alors effectuée grâce à une méthode multicritère de manière à respecter au mieux les relations attendues. Une mise en œuvre est présentée sur des cas d'étude jouets et sur un cas réel fourni par un service de l'Etat gestionnaire de réseau routier. Nous discutons enfin l'extension du modèle proposé pour traiter la prise en compte des relations pour d'autres applications que la migration de données thématiques / With the large availability of reference topographic data, creating geographic data is not exclusive to experts of geographic information any more. More and more users rely on reference data to create their own data, hereafter called thematic data. Reference data then play the role of support for thematic data. Thematic data make sense by themselves, but even more by their relations with topographic data. Not taking into account the relations between thematic and topographic data during processes that modify the former or the latter may cause inconsistencies, especially for processes that are related to changing the level of detail. The objective of this thesis is to define a methodology to preserve the consistency between thematic and topographic when the level of detail is modified. This thesis focuses on the adaptation of thematic data after a modification of topographic data: we call this process thematic data migration. We first propose a model for the migration of punctual thematic data hosted by a network. This model is composed of: (1) a model to describe the referencing of thematic data on topographic data using spatial relations (2) a method to re-locate thematic data based on these relations. The approach consists in identifying the expected final relations according to the initial relations and the modifications of topographic data between the initial and the final state. The thematic data are then re-located using a multi-criteria method in order to satisfy, as much as possible, the expected relations. An implementation is presented on toy problems and on a real use case provided by a French public authority in charge of road network management. The extension of the proposed model to take into account the relations for other applications than thematic data migration is also discussed
22

Arquitetura de software para integração de informações geográficas de sensores e voluntários na gestão de risco de inundação / Software architecture for integration of sensor and volunteered geographic information in the flood risk management

Castanhari, Raul Eduardo Simoni 08 April 2016 (has links)
Desastres naturais são fenômenos que causam grandes danos às pessoas em áreas urbanas e rurais, motivando medidas de prevenção e reação. Se múltiplas fontes de informação são consideradas, tais medidas podem ser mais assertivas e efetivas. Porém, a integração de dados heterogêneos ainda impõe desafios devido às diferenças em suas estruturas. Para preencher essa lacuna, esta pesquisa apresenta uma arquitetura orientada a serviços, como parte de uma plataforma geoespacial para gestão de risco de desastres, a qual visa apoiar a integração de dados de sensores e de voluntários relacionados a inundações. Como resultado, a composição dos serviços descritos pelos componentes arquiteturais possibilita a integração entre dados de sensores e voluntários usando algoritmos diferentes de forma flexível e automática. / Natural disasters are phenomena that can cause great damage to people in urban and rural areas, thus motivating preventive and reactive measures. If multiple sources of information are considered, such measures can be more assertive and effective. However, the integration of heterogeneous data still poses challenges due to the differences in their structures. To fill this gap, this paper presents a service-oriented architecture, as part of a geospatial platform for disaster risk management, which aims to support the integration of sensor data streams and Volunteered Geographic Information (VGI) related to floods. The architectural components are implemented as Web services, and their composition enables the integration between sensor data and VGI using several algorithms in a flexible and automated manner. As result, the composition of the services described by the architectural components allows the integration of sensor and volunteered data by using diverse algorithms in a flexible and automated way.
23

Simulation von Annotationen zur gemeinschaftlichen Nutzung geographischer Daten

Voegler, Jens, Weber, Gerhard 22 May 2014 (has links) (PDF)
No description available.
24

Estimação espacial da migração de consumidores residenciais para a tarifa branca em sistemas de distribuição de energia elétrica /

Cunha, Pedro Paulo. January 2018 (has links)
Orientador: Antonio Padilha Feltrin / Resumo: Neste trabalho o espaço geográfico é incorporado ao estudo da análise das potencialidades de migração de consumidores residenciais para uma nova opção tarifária: a tarifa branca. Os trabalhos avaliados no tema não incorporam a análise espacial de dados geográficos. Em geral apresentam as classes de consumo que mais se beneficiam com a adoção da nova opção tarifária e aspectos relacionados à estrutura tarifária de energia elétrica no Brasil. No entanto, o estudo das características do lugar onde pode ser mais provável a migração massiva de consumidores para a tarifa branca pode trazer informações relevantes para direcionar a atenção das distribuidoras de energia na aquisição de medidores eletrônicos e outros equipamentos para determinadas regiões da área urbana do município. Promove-se dessa forma um melhor dimensionamento do sistema elétrico. Os resultados deste trabalho são mapas de probabilidades úteis para indicar as subáreas onde há maior probabilidade de migração de consumidores residenciais para a tarifa branca. Esses mapas indicam que algumas regiões da cidade como a porção central e leste para os anos de 2018 e 2019 exibem maior probabilidade de unidades consumidoras aptas a migrarem para a tarifa branca. Portanto, há nessas regiões uma tendência de redução da demanda de ponta (ou de pico). Espera-se uma mudança de perfil de carga daqueles alimentadores que atendem regiões onde há maior quantidade de consumidores que irão migrar para a tarifa branca. O espaço é incorp... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: In this work the geographic space is incorporated to the study of the analysis of the potentialities of migration of residential consumers for a new tariff option: the white tariff. The works evaluated in the theme do not incorporate the spatial analysis of geographic data. In general, they present the classes of consumption that most benefit from the adoption of the new tariff option and aspects related to the tariff structure of electric energy in Brazil. However, the study of the characteristics of the place where the massive migration of consumers to the white tariff may be most likely to bring relevant information to direct the attention of energy distributors in the acquisition of electronic meters and other equipment for certain regions of the urban area of the County. In this way, a better design of the electrical system is promoted. The results of this work are useful probability maps to indicate the subareas where there is a greater probability of migration of residential consumers to the white tariff. These maps indicate that some regions of the city such as the central and eastern portions for the years 2018 and 2019 are more likely to be consumer units able to migrate to the white tariff. Therefore, there is a tendency in these regions to reduce the peak (or peak) demand. A load profile change is expected from those feeders serving regions where there are more consumers who will migrate to the white tariff. The space is incorporated in this work through technique... (Complete abstract click electronic access below) / Mestre
25

Incorporando dados espaciais vagos em data warehouses geográficos: a proposta do tipo abstrato de dados vaguegeometry

Carniel, Anderson Chaves 09 October 2014 (has links)
Made available in DSpace on 2016-06-02T19:06:18Z (GMT). No. of bitstreams: 1 6327.pdf: 10668384 bytes, checksum: 806ac414d43596c366d93b4bfc0febe0 (MD5) Previous issue date: 2014-10-09 / Universidade Federal de Minas Gerais / A data warehouse is a solution for organizing and storing multidimensional data related to decision-making processes in companies, generating a historical, highly voluminous, subject-oriented and nonvolatile database. A geographic data warehouse (GDW) additio¬nally to the conventional data storage (i.e. numeric and alphanumeric data), stores spatial data as attributes in dimension tables or as measures in fact tables, storing data represented by geometries. Points, lines and polygons are examples of spatial data types. While spatial data currently stored in GDWs are crisp, i.e., they have exact location in the space, strict interiors and well-defined boundaries, geographic applications have required the storage of vague spatial data, which have inaccurate location, inexact interiors or uncertain bounda¬ries. This Master s research aims at incorporating vague spatial data to GDWs. More speci¬fically, we propose and implement a new abstract data type (ADT) called VagueGeometry to represent vague spatial data in the Spatial Database Management System (SDBMS) Post- greSQL/PostGIS. The proposal of the ADT VagueGeometry encompasses the issue of phy¬sical storage for vague spatial data, which are complex and can have several disjoint parts. It also focuses on definitions of operations to handle vague spatial objects, such as vague topological predicates and its operators. Experimental evaluations were conducted in order to assess the performance of the ADT VagueGeometry in comparison to available solutions, such as implementation of vague topological predicates utilizing existing operations of the PostGIS. The proposed ADT VagueGeometry shown reductions in query processing with vague topological predicates from 81.63% to 90.34% in spatial databases and reductions from 92.46% a 95.20% in GDW environments. This Master s project, therefore, advances in the state of art in GDWs to study this gap in the literature. Additionally, fuzzy models to represent vague spatial data was also studied, and as a result, a preliminary proposal of a ADT, called as FuzzyGeometry, was also developed. / Um data warehouse é uma solução para a organização e o armazenamento de dados mul-tidimensionais relacionados a tomada de decisão estratégica em empresas, constituindo um banco de dados histórico, volumoso, orientado ao assunto e não volátil. Um data warehouse geográfico (DWG) adicionalmente ao armazenamento de dados convencionais (tais como dados numéricos e alfanuméricos), armazena dados espaciais como atributos em tabelas de dimensão ou como medidas em tabelas de fatos, ou seja, armazena dados representados por meio de geometrias. Pontos, linhas e polígonos são exemplos de dados espaciais armazena¬dos. Enquanto estes dados armazenados atualmente em DWGs sao crisp, ou seja, possuem localização, interiores e fronteiras bem definidas, aplicações geográficas tem demandado o armazenamento de dados espaciais vagos, os quais possuem localização, interiores ou fronteiras incertas. Esta pesquisa de mestrado visa incorporar dados espaciais vagos em DWGs. Mais especificamente, foi proposto e implementado um novo tipo abstrato de dados (TAD), denominado VagueGeometry, para representar dados espaciais vagos no Sistema Gerenciador de Banco de Dados (SGBD) PostgreSQL com a extensão espacial PostGIS. A proposta do TAD VagueGeometry engloba a proposta de uma forma de armazenamento interna para os dados espaciais vagos, os quais são complexos e podem possuir diversas partes disjuntas. Isso também inclui a definição de operações para manipular objetos espa¬ciais vagos, tais como os relacionamentos topológicos vagos e seus operadores. Avaliações experimentais foram conduzidas para medir o desempenho do TAD VagueGeometry frente a soluções existentes, tal como a implementação de predicados topológicos vagos reuti¬lizando operações existentes do PostGIS. A proposta do TAD VagueGeometry apresentou reduções no tempo de processamento de predicados topológicos vagos de 81,63% a 90,34% em bancos de dados espaciais e reduções de 92,46% a 95,20% em ambientes de DWG. Este trabalho, portanto, avança no estado da arte em DWGs de forma a preencher essa lacuna existente na literatura. Adicionalmente, modelos fuzzy para representação dos dados espa¬ciais vagos também foram estudados e uma proposta preliminar de um TAD, denominado FuzzyGeometry, também foi desenvolvida.
26

Modelo de procedência para auxiliar na análise da qualidade do dado geográfico

Santos, Renata Ribeiro dos 09 August 2016 (has links)
Submitted by Aelson Maciera (aelsoncm@terra.com.br) on 2017-03-29T19:09:28Z No. of bitstreams: 1 DissRRS.pdf: 3751863 bytes, checksum: 950bef628d03f26a109436e96c9ac337 (MD5) / Approved for entry into archive by Ronildo Prado (ronisp@ufscar.br) on 2017-04-11T13:45:04Z (GMT) No. of bitstreams: 1 DissRRS.pdf: 3751863 bytes, checksum: 950bef628d03f26a109436e96c9ac337 (MD5) / Approved for entry into archive by Ronildo Prado (ronisp@ufscar.br) on 2017-04-11T13:45:15Z (GMT) No. of bitstreams: 1 DissRRS.pdf: 3751863 bytes, checksum: 950bef628d03f26a109436e96c9ac337 (MD5) / Made available in DSpace on 2017-04-11T13:53:54Z (GMT). No. of bitstreams: 1 DissRRS.pdf: 3751863 bytes, checksum: 950bef628d03f26a109436e96c9ac337 (MD5) Previous issue date: 2016-08-09 / Não recebi financiamento / The quality of the geographic data must be a relevant concern for providers and consumers of this type of data because the manipulation and analysis of low quality geographic data may result in errors, which will be propagated through the consequent data. Thus it is important to properly document the information which allows for certifying the quality of the geographic data. In order to provide a minimum amount of metadata for such purpose, this dissertation presents an approach based on the provenance of the geographic data, which corresponds to the information about the history of such data from its origin until the processes that resulted in its current state. For this purpose, a provenance model called ProcGeo was proposed, in which it was defined a minimum amount of metadata that must be considered for the analysis of the quality of a certain geographic data. Although a few works and geographic metadata standards, such as Federal Geographic Data Committee (FGDC) and ISO 19115, consider the information about the provenance in the analysis of the quality of geographic data, it´s the opinion of the author that some metadata considered important for this purpose are not adequately contemplated. In this work, the prototype of an interface called ProcGeoInter was also implemented, aiming to guarantee the completeness and correctness in the filling out of the defined metadata in the ProcGeo model as well as the visualization of their content. The validation of the ProcGeo model and of the ProcGeoInter interface were made through tests and surveys applied to providers and consumers of geographic data. As a means of comparison, the interface for filling out and visualization of metadata available by SIG Quantum GIS (plugin Metatools) was used, which implements the FGDC geographic metadata standard. The obtained results indicated that the metadata defined in the ProcGeo model helped the geographic data provider in the description of the provenance of such data, when compared to those defined in the FGDC geographic metadata standard. Through the consumer´s focus it was possible to notice that the information filled out in the metadata defined by the ProcGeo favored the analysis of the quality of the consumed data. It was clear that both providers and consumers do not possess the habit of providing or consuming the information predicted in the FGDC and ISO 19115 geographic metadata standards. / A qualidade do dado geográfico deve ser uma preocupação relevante para provedores e consumidores desse tipo de dado, pois a manipulação e análise de um dado geográfico com baixa qualidade podem resultar em erros que vão se propagar nos dados gerados a partir desse. Assim, é importante que a informação que permita atestar a qualidade do dado geográfico seja adequadamente documentada. Com o propósito de oferecer um conjunto mínimo de metadados para essa finalidade, esse trabalho apresenta uma abordagem baseada na procedência do dado geográfico, que corresponde à informação sobre a história do dado, desde a sua origem até os processos que resultaram no seu estado atual. Para tanto, foi proposto um modelo de procedência denominado ProcGeo no qual foi definido um conjunto mínimo de metadados que devem ser considerados para a análise da qualidade de um dado geográfico. Embora alguns trabalhos e padrões de metadados geográficos, como o Federal Geographic Data Committee (FGDC) e o ISO 19115, considerem a informação da procedência para a análise da qualidade do dado geográfico, sob o ponto de vista da autora deste trabalho, alguns metadados considerados importantes para essa finalidade não são adequadamente contemplados. Neste trabalho também foi implementado o protótipo de uma interface denominada ProcGeoInter, que tem como finalidade garantir a corretude e completude do preenchimento dos metadados definidos no modelo ProcGeo e a visualização do conteúdo dos mesmos. A validação do modelo ProcGeo e da interface ProcGeoInter foram realizados por meio de testes e questionários aplicados a provedores e consumidores de dados geográficos. Para efeito de comparação, foi considerada a interface para preenchimento e visualização de metadados disponibilizada no SIG Quantum GIS (plugin Metatoools), que implementa o padrão de metadados geográficos FGDC. Os resultados obtidos indicaram que os metadados definidos no modelo ProcGeo auxiliaram o provedor de dados geográficos na descrição da procedência desses dados, quando comparados aos definidos no padrão de metadados geográficos FGDC. Pelo foco do consumidor foi possível perceber que as informações preenchidas nos metadados definidos pelo ProcGeo favoreceram a análise da qualidade dos dados consumidos. Ficou evidente que tanto provedores quanto consumidores não possuem o hábito de prover ou consumir as informações previstas nos padrões de metadados geográficos FGDC e ISO 19115.
27

Arquitetura de software para integração de informações geográficas de sensores e voluntários na gestão de risco de inundação / Software architecture for integration of sensor and volunteered geographic information in the flood risk management

Raul Eduardo Simoni Castanhari 08 April 2016 (has links)
Desastres naturais são fenômenos que causam grandes danos às pessoas em áreas urbanas e rurais, motivando medidas de prevenção e reação. Se múltiplas fontes de informação são consideradas, tais medidas podem ser mais assertivas e efetivas. Porém, a integração de dados heterogêneos ainda impõe desafios devido às diferenças em suas estruturas. Para preencher essa lacuna, esta pesquisa apresenta uma arquitetura orientada a serviços, como parte de uma plataforma geoespacial para gestão de risco de desastres, a qual visa apoiar a integração de dados de sensores e de voluntários relacionados a inundações. Como resultado, a composição dos serviços descritos pelos componentes arquiteturais possibilita a integração entre dados de sensores e voluntários usando algoritmos diferentes de forma flexível e automática. / Natural disasters are phenomena that can cause great damage to people in urban and rural areas, thus motivating preventive and reactive measures. If multiple sources of information are considered, such measures can be more assertive and effective. However, the integration of heterogeneous data still poses challenges due to the differences in their structures. To fill this gap, this paper presents a service-oriented architecture, as part of a geospatial platform for disaster risk management, which aims to support the integration of sensor data streams and Volunteered Geographic Information (VGI) related to floods. The architectural components are implemented as Web services, and their composition enables the integration between sensor data and VGI using several algorithms in a flexible and automated manner. As result, the composition of the services described by the architectural components allows the integration of sensor and volunteered data by using diverse algorithms in a flexible and automated way.
28

Geografické informační systémy v dopravě / Geographics Information Systems in Transportation

Souček, Václav Unknown Date (has links)
The work is focused on the issues associated with the use of geographical information systems in transport. Of the various types of transport was chosen railway transport for its great potential particularly in the field of freight transport, but also because it is a relatively environmentally friendly. This fact is also well known to the leaders of the European Union, who are engaged in the field of transportation. The European Commission in its documents (green and white papers) gives accent on the development of railway transportation and combined transportation, because this is the path to secure the sustainable development of transport. In the course of this study the current state of information systems several problems were discovered. One problem is the fragmentation of the partial information systems and the associated strong administrative burden. This situation stems both from the incomplete legislative framework, but also from the lack of the concept and awareness of the managerial positions. This work deals with other selected issues. The first is the area of designing the data model topology track that satisfies the requirements set out in legislation, both European and national level. The data model was designed with regard to a sufficient degree of variability. The work contains a section dedicated to the implementation of the data model and solution design of problems associated with visualization arcs. Another area is the collection of geographic data. Data collection is one of the key tasks in the implementation and maintenance of the information system. The acquisition of the geographical data can be lengthy and costly. We therefore suggest how to use inertial measurement in acquisition of topological data. This method could speed up the entire process of data capturing with sufficient precision and reduce the costs to the acceptable range.
29

Simulation von Annotationen zur gemeinschaftlichen Nutzung geographischer Daten

Voegler, Jens, Weber, Gerhard January 2010 (has links)
No description available.
30

Automating Geospatial RDF Dataset Integration and Enrichment / Automatische geografische RDF Datensatzintegration und Anreicherung

Sherif, Mohamed Ahmed Mohamed 12 December 2016 (has links) (PDF)
Over the last years, the Linked Open Data (LOD) has evolved from a mere 12 to more than 10,000 knowledge bases. These knowledge bases come from diverse domains including (but not limited to) publications, life sciences, social networking, government, media, linguistics. Moreover, the LOD cloud also contains a large number of crossdomain knowledge bases such as DBpedia and Yago2. These knowledge bases are commonly managed in a decentralized fashion and contain partly verlapping information. This architectural choice has led to knowledge pertaining to the same domain being published by independent entities in the LOD cloud. For example, information on drugs can be found in Diseasome as well as DBpedia and Drugbank. Furthermore, certain knowledge bases such as DBLP have been published by several bodies, which in turn has lead to duplicated content in the LOD . In addition, large amounts of geo-spatial information have been made available with the growth of heterogeneous Web of Data. The concurrent publication of knowledge bases containing related information promises to become a phenomenon of increasing importance with the growth of the number of independent data providers. Enabling the joint use of the knowledge bases published by these providers for tasks such as federated queries, cross-ontology question answering and data integration is most commonly tackled by creating links between the resources described within these knowledge bases. Within this thesis, we spur the transition from isolated knowledge bases to enriched Linked Data sets where information can be easily integrated and processed. To achieve this goal, we provide concepts, approaches and use cases that facilitate the integration and enrichment of information with other data types that are already present on the Linked Data Web with a focus on geo-spatial data. The first challenge that motivates our work is the lack of measures that use the geographic data for linking geo-spatial knowledge bases. This is partly due to the geo-spatial resources being described by the means of vector geometry. In particular, discrepancies in granularity and error measurements across knowledge bases render the selection of appropriate distance measures for geo-spatial resources difficult. We address this challenge by evaluating existing literature for point set measures that can be used to measure the similarity of vector geometries. Then, we present and evaluate the ten measures that we derived from the literature on samples of three real knowledge bases. The second challenge we address in this thesis is the lack of automatic Link Discovery (LD) approaches capable of dealing with geospatial knowledge bases with missing and erroneous data. To this end, we present Colibri, an unsupervised approach that allows discovering links between knowledge bases while improving the quality of the instance data in these knowledge bases. A Colibri iteration begins by generating links between knowledge bases. Then, the approach makes use of these links to detect resources with probably erroneous or missing information. This erroneous or missing information detected by the approach is finally corrected or added. The third challenge we address is the lack of scalable LD approaches for tackling big geo-spatial knowledge bases. Thus, we present Deterministic Particle-Swarm Optimization (DPSO), a novel load balancing technique for LD on parallel hardware based on particle-swarm optimization. We combine this approach with the Orchid algorithm for geo-spatial linking and evaluate it on real and artificial data sets. The lack of approaches for automatic updating of links of an evolving knowledge base is our fourth challenge. This challenge is addressed in this thesis by the Wombat algorithm. Wombat is a novel approach for the discovery of links between knowledge bases that relies exclusively on positive examples. Wombat is based on generalisation via an upward refinement operator to traverse the space of Link Specifications (LS). We study the theoretical characteristics of Wombat and evaluate it on different benchmark data sets. The last challenge addressed herein is the lack of automatic approaches for geo-spatial knowledge base enrichment. Thus, we propose Deer, a supervised learning approach based on a refinement operator for enriching Resource Description Framework (RDF) data sets. We show how we can use exemplary descriptions of enriched resources to generate accurate enrichment pipelines. We evaluate our approach against manually defined enrichment pipelines and show that our approach can learn accurate pipelines even when provided with a small number of training examples. Each of the proposed approaches is implemented and evaluated against state-of-the-art approaches on real and/or artificial data sets. Moreover, all approaches are peer-reviewed and published in a conference or a journal paper. Throughout this thesis, we detail the ideas, implementation and the evaluation of each of the approaches. Moreover, we discuss each approach and present lessons learned. Finally, we conclude this thesis by presenting a set of possible future extensions and use cases for each of the proposed approaches.

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