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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.
41

Správa a popis geografických dat v oblasti životního prostředí České republiky / Management and description of geographic data in the field of environment of the Czech Republic

Zrzavecká, Lada January 2016 (has links)
This thesis describes and analyzes the current state of environmental management of geographic data within geoinformation infrastructure of the Czech Republic in response to European legislation. The work is divided into four main parts. The first part deals with geoinformation infrastructure of the Czech Republic in its basic components due to the efficiency of the management of geographic data. Another part deals with the general characteristics of geospatial data underlying the description methods, organization and retrieval in the next section. The final part of its qualitative research describes in detail the management of geospatial data in the environmental sector, which is affected by the phenomenon of the implementation of INSPIRE and draws conclusions and recommendations. The work also supports the analysis of the availability of data sources for the implementation of the INSPIRE directive, the questionnaire used as a guide for research purposes, to illustrate the services Geoportal three pictures. Powered by TCPDF (www.tcpdf.org)
42

Environmental Trail Suitability in the Proposed Bästeträsk National Park, Gotland : A Multi-Criteria Decision Analysis Using GIS

Palyza, Jan January 2023 (has links)
This master’s thesis determines trail suitability in the context of environmental area sensitivity, closely focusing on a proposed Bästeträsk National Park, Gotland, Sweden. The current relative low usage of the area is expected to significantly increase its tourism flow once the proposed national park is established, as the demand for nature-based tourism and recreation is growing. However, due to its pristine landscapes, myriad endemic and red-listed species, and rare geomorphological phenomena, there is a need to closely review the destination’s environmental sensitivity and potential recreational adverse impacts on the area’s ecosystem services. Consequently, the research reviews Volunteered Geographic Data within the studied area and employs Geographic Information Systems-based Multi-Criteria Decision Analysis to determine environmental trail suitability. The research identified that more than half of the studied area exhibits substantial environmental sensitivity. Additionally, it highlights that multiple used and established trails intersect considerably sensitive areas, which must be considered for future tourism planning to attain sustainable destination development. Moreover, the study furthers on the requisite to recognise nature-based activities beyond the means of low impact due to their increasing popularity and anthropogenic impacts.
43

Online systém pro vizuální geo-lokalizaci v přírodním prostředí / Online System for Visual Geo-Localization in Natural Environment

Pospíšil, Miroslav January 2018 (has links)
The goal of this master thesis is creation of an online system serving as a performing application for presentation results of visual geo-localization in nature and mountain environment. The system offers the users to choose one of the pre-defined photographs or~to~upload one's own photography while choosing a file or inserting an URL address. The~system will localizate a camera of a given image based on a visual geo-localization. The~geo-localization uses the mountain horizon as a key characteristic when searching for similar horizons. The~curve line of the horizon is extracted by a fully automatic algorithm based on supervised learning and dynamic programming. Visual geo-localization running on the server which using new inversed index with cache politic. This allows further scaling of the system. The server processing detected horizon curve and respond with set of the best candidates on results. Results are visualised to the user in form of classic map, detailed sattelite view and rendering of found panorama.
44

Automating Geospatial RDF Dataset Integration and Enrichment

Sherif, Mohamed Ahmed Mohamed 12 May 2016 (has links)
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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