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網頁地理關聯性之分析與研究 / The Analysis of Geographic Relations of Internet Information黃建達, Huang, Jian Da Unknown Date (has links)
近幾年來,有關地理資訊的網頁搜尋越來越受到重視。傳統的網頁搜尋引擎無法反應使用者查詢和網頁文件之間的地理關聯性。在一些情況下,我們希望網路搜尋引擎能夠考慮使用者查詢與網頁文件間的地理相關性,以提升搜尋的準確度。
我們的研究透過包圍矩形模型(Bounding Rectangle Model;BR Model)以搜尋與使用者查詢之地理相關程度較高的網頁文件。 使用者僅需輪入文字的查詢,即能得到相符結果的網頁文件。首先,我們建立一個地名辭典以找出使用者查詢與網頁文件內出現的地名及空間資料,接著我們利用空間資料建立空間索引項(spatial index term)集合,用來表示使用者查詢與網頁文件內的地理範圍,最後再透過使用者查詢與網頁文件的空間索引項集合計算兩者之間的地理相似程度,以找出與使用者查詢有較高地理關聯性的網頁文件。
此篇論文的貢獻在於我們提一套完整資訊檢索模型架構的方法,分析使用者查詢與網頁文件之間的地理關聯性,使用者藉由輸入文字查詢即能得到相符地理關聯性的網頁文件。 / Geographic web search becomes increasingly popular in recent years. Traditional web search engine, such as Google and Yahoo, can not accommodate geographic relevance between user queries and internet documents. Hence, they can not retrieve geographic related information from user queries. However, in many cases, the geographic relevance between user queries and internet documents could enhance the accuracy of this type of searches.
In this thesis, we propose a mechanism that uses the Bounding Rectangle Model (BR Model) to retrieve geographic relevant internet documents in response to user queries. Users provide only the conventional input queries (keywords) and our search engine will return the geographic relevant results. Our method can be classified into the following three steps. In the first step, we create a gazetteer and use it to relate the user query’s geographic terms in internet documents. In the next step, we use the spatial data to build a set of spatial index terms that represents the geographic scope of user query and internet documents. And then we use these spatial index terms to calculate degree of geographic similarity between user query and internet documents to identify highly relevant geographic internet documents.
We implemented a prototype search engine using our approach. The experiment results show that we can successfully retrieve geographic relevant data through this mechanism and provide more accurate search results.
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Utilisation de systèmes d'information géographique pour l'évaluation des risques liés à la dégradation du pergélisol. Étude de cas : Tasiujaq, Nunavik, QuébecGrandmont, Katerine 08 1900 (has links)
Les régions nordiques à pergélisol seront largement affectées par l'augmentation prévue des
températures. Un nombre croissant d’infrastructures qui étaient autrefois construites avec
confiance sur des sols gelés en permanence commencent déjà à montrer des signes de
détérioration. Les processus engendrés par la dégradation du pergélisol peuvent causer des
dommages importants aux infrastructures et entrainer des coûts élevés de réparation. En
conséquence, le contexte climatique actuel commande que la planification des projets dans
les régions nordiques s’effectue en tenant compte des impacts potentiels de la dégradation
du pergélisol. Ce mémoire porte sur l’utilisation de systèmes d’information géographique
(SIG) appliqués à l’évaluation du potentiel d’aménagement des territoires situés en milieu
de pergélisol. En utilisant une approche SIG, l’objectif est d’élaborer une méthodologie
permettant de produire des cartes d'évaluation des risques afin d’aider les collectivités
nordiques à mieux planifier leur environnement bâti. Une analyse multi-échelle du paysage
est nécessaire et doit inclure l'étude des dépôts de surface, la topographie, ainsi que les
conditions du pergélisol, la végétation et les conditions de drainage. La complexité de
l'ensemble des interactions qui façonnent le paysage est telle qu'il est pratiquement
impossible de rendre compte de chacun d'eux ou de prévoir avec certitude la réponse du
système suite à des perturbations. Ce mémoire présente aussi certaines limites liées à
l’utilisation des SIG dans ce contexte spécifique et explore une méthode innovatrice
permettant de quantifier l'incertitude dans les cartes d'évaluation des risques. / Northern regions underlain by permafrost will largely be affected by the projected increase
in air temperature. A growing number of structures that were once built with great
confidence on perennially frozen soils are already starting to show signs of deterioration.
Processes caused by permafrost degradation can cause significant damages to infrastructure
and require high costs of repair. The current climatic context therefore commands that the
implementation of projects in permafrost regions follows a well-thought planning in order
to account for the potential impacts of permafrost degradation. This thesis focuses on the
use of geographic information systems (GIS) applied to the identification of the
development potential of communities located in permafrost regions. Using a GIS
approach, the goal is to develop a methodology to produce risk-assessment maps to help
northern communities better plan their built environment. A multi-scale analysis of the
landscape is necessary and should include the investigation of surficial deposits,
topography, as well as permafrost, vegetation and drainage conditions. The complexity of
all the interactions that shape the landscape is such that it is virtually impossible to account
for all of them or to predict with certainty the response of the system following
disturbances. This research also presents some of the limitations to the use of GIS in this
specific context and explores an innovative method for quantifying uncertainty in risk-assessment
maps.
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Multi-sources fusion based vehicle localization in urban environments under a loosely coupled probabilistic frameworkWei, Lijun 17 July 2013 (has links) (PDF)
In some dense urban environments (e.g., a street with tall buildings around), vehicle localization result provided by Global Positioning System (GPS) receiver might not be accurate or even unavailable due to signal reflection (multi-path) or poor satellite visibility. In order to improve the accuracy and robustness of assisted navigation systems so as to guarantee driving security and service continuity on road, a vehicle localization approach is presented in this thesis by taking use of the redundancy and complementarities of multiple sensors. At first, GPS localization method is complemented by onboard dead-reckoning (DR) method (inertial measurement unit, odometer, gyroscope), stereovision based visual odometry method, horizontal laser range finder (LRF) based scan alignment method, and a 2D GIS road network map based map-matching method to provide a coarse vehicle pose estimation. A sensor selection step is applied to validate the coherence of the observations from multiple sensors, only information provided by the validated sensors are combined under a loosely coupled probabilistic framework with an information filter. Then, if GPS receivers encounter long term outages, the accumulated localization error of DR-only method is proposed to be bounded by adding a GIS building map layer. Two onboard LRF systems (a horizontal LRF and a vertical LRF) are mounted on the roof of the vehicle and used to detect building facades in urban environment. The detected building facades are projected onto the 2D ground plane and associated with the GIS building map layer to correct the vehicle pose error, especially for the lateral error. The extracted facade landmarks from the vertical LRF scan are stored in a new GIS map layer. The proposed approach is tested and evaluated with real data sequences. Experimental results with real data show that fusion of the stereoscopic system and LRF can continue to localize the vehicle during GPS outages in short period and to correct the GPS positioning error such as GPS jumps; the road map can help to obtain an approximate estimation of the vehicle position by projecting the vehicle position on the corresponding road segment; and the integration of the building information can help to refine the initial pose estimation when GPS signals are lost for long time.
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Visions d’État : deux systèmes d'informations géographiques dans la « gouvernance »Sibille, Bastien 05 1900 (has links)
L'administration fédérale canadienne et la Commission européenne ont construit, dans le courant des années 2000, deux réseaux de Systèmes d'informations géographiques (SIG) : le Système national d'information forestière au Canada, et l'Infrastructure d'information géographique dans la Communauté européenne. Ces SIG permettent le traitement géographique de données sociales et environnementales ainsi que leur représentation sur des cartes.
Nous appréhendons ces deux réseaux de SIG sous l'angle de leur valeur heuristique : leur analyse nous permet d'étudier les configurations institutionnelles dans lesquelles ils ont été développés, c'est-à-dire, dans ces cas précis, ce qu'il est convenu d'appeler la « gouvernance ». Les SIG sont des instruments de mesure et de représentation de certains phénomènes : ils appartiennent à la classe des instruments d'objectivation. En tant qu'instruments d'objectivation, ils nous permettent de discuter deux éléments théoriques de la « gouvernance » : le rapport entre les administrations centrales et les administrations locales ; le rapport entre les administrations étatiques et les organisations non-étatiques. A travers cette discussion, nous montrons d'une part que la réarticulation de paliers de gouvernement différents ne signifie pas, comme cela a pu être écrit, un retrait de l'administration centrale au profit des administrations locales, mais au contraire une manière de contrôler plus étroitement celles-ci. Nous montrons d'autre part que cette renégociation des rapports entre les administrations centrales et locales ne s'accompagne pas, en pratique, d’une renégociation des rapports entre administrations étatiques et organisations non-étatiques. En révélant que les données non-étatiques ne sont pas intégrées dans les réseaux de SIG étatiques, nous relativisons les théories qui voient dans la « gouvernance » un mode de gouvernement ouvert aux organisations non-étatiques. Cela nous conduit à approfondir la piste qui envisage les instruments étatiques d'objectivation comme des moyens d'écarter de l'objectivation des phénomènes sociaux ou naturels les éléments qui contredisent l'action gouvernementale.
Cette exégèse politique de deux ensembles de programmes informatiques particuliers – les SIG – nous amène, en conclusion, à proposer de considérer certains programmes informatiques comme des institutions politiques. / During the 1990s, Canada’s federal government and the European Commission established two networks of geographic information systems (GIS): the National Forest Information System in Canada and the Infrastructure for Spatial Information in the European Union. These two systems permit social and environment facts to be studied geographically and to be mapped.
In this thesis, we emphasize the heuristic value of these two networks of geographic information systems: an analysis of them allows us to better understand the institutional configurations that existed during their development, that is to say, in our cases, what is called “governance”. As instruments that measure and represent phenomena, GIS belong to knowledge tools. As knowledge tools, they allow us to discuss two issues of “governance” theories: relationships between central and local administrations, and relationships between state and non-state organizations. This discussion leads us to show, on the one hand, that the reorganization of different levels of government does not signify, as is described elsewhere in the literature, the retreat of central administrations in favor of local administrations, but is rather a means for more forcefully controlling them. On the other hand, we show that the renegotiation of relationships between central and local administrations is not accompanied, in reality, by a negotiation of relationships with non-state organizations. In light of the fact that non-state organizations are not integrated in states’ GIS networks, we must revisit theories of “governance” that foresee governments as more open to civil society. This helps us to understand how knowledge tools can be used in order to exclude certain facts from State's sight.
In conclusion, this political analysis of two specific software – GIS – leads us to propose that some software can be considered as political institutions.
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Utilisation de systèmes d'information géographique pour l'évaluation des risques liés à la dégradation du pergélisol. Étude de cas : Tasiujaq, Nunavik, QuébecGrandmont, Katerine 08 1900 (has links)
Les régions nordiques à pergélisol seront largement affectées par l'augmentation prévue des
températures. Un nombre croissant d’infrastructures qui étaient autrefois construites avec
confiance sur des sols gelés en permanence commencent déjà à montrer des signes de
détérioration. Les processus engendrés par la dégradation du pergélisol peuvent causer des
dommages importants aux infrastructures et entrainer des coûts élevés de réparation. En
conséquence, le contexte climatique actuel commande que la planification des projets dans
les régions nordiques s’effectue en tenant compte des impacts potentiels de la dégradation
du pergélisol. Ce mémoire porte sur l’utilisation de systèmes d’information géographique
(SIG) appliqués à l’évaluation du potentiel d’aménagement des territoires situés en milieu
de pergélisol. En utilisant une approche SIG, l’objectif est d’élaborer une méthodologie
permettant de produire des cartes d'évaluation des risques afin d’aider les collectivités
nordiques à mieux planifier leur environnement bâti. Une analyse multi-échelle du paysage
est nécessaire et doit inclure l'étude des dépôts de surface, la topographie, ainsi que les
conditions du pergélisol, la végétation et les conditions de drainage. La complexité de
l'ensemble des interactions qui façonnent le paysage est telle qu'il est pratiquement
impossible de rendre compte de chacun d'eux ou de prévoir avec certitude la réponse du
système suite à des perturbations. Ce mémoire présente aussi certaines limites liées à
l’utilisation des SIG dans ce contexte spécifique et explore une méthode innovatrice
permettant de quantifier l'incertitude dans les cartes d'évaluation des risques. / Northern regions underlain by permafrost will largely be affected by the projected increase
in air temperature. A growing number of structures that were once built with great
confidence on perennially frozen soils are already starting to show signs of deterioration.
Processes caused by permafrost degradation can cause significant damages to infrastructure
and require high costs of repair. The current climatic context therefore commands that the
implementation of projects in permafrost regions follows a well-thought planning in order
to account for the potential impacts of permafrost degradation. This thesis focuses on the
use of geographic information systems (GIS) applied to the identification of the
development potential of communities located in permafrost regions. Using a GIS
approach, the goal is to develop a methodology to produce risk-assessment maps to help
northern communities better plan their built environment. A multi-scale analysis of the
landscape is necessary and should include the investigation of surficial deposits,
topography, as well as permafrost, vegetation and drainage conditions. The complexity of
all the interactions that shape the landscape is such that it is virtually impossible to account
for all of them or to predict with certainty the response of the system following
disturbances. This research also presents some of the limitations to the use of GIS in this
specific context and explores an innovative method for quantifying uncertainty in risk-assessment
maps.
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The Use of Geographic Information Systems by Law Enforcement Agencies and Its Impact on Police PerformanceUlvi, Kun 04 February 2014 (has links)
Do we know whether the use of geographic information systems (GIS) in law enforcement agencies increases police performance? This study examines the impact of GIS use to police performance outcomes in cities and counties of the U.S. between 2000 and 2007. Current research uses computerized mapping conceptualization to operationalize its measurement. Second, the police performance methodological context is used to measure the organizational impact of GIS. Finally, a new theoretical framework, information technology capacity that combines organizational, environmental and managerial factors to explain IT applications, is used to encompass most relevant dimensions of the subject matter. Findings indicate that the use of GIS in police agencies increased sharply between 2003 and 2007. Additionally, the contribution of GIS use on police performance was found to be statistically significant, but in the opposite direction. Overall, results of the present study indicate significant links between crime rate (DV) and independent variables (IV) in law enforcement agencies. IVs are having a professional form of government andfull time specialized crime analysis personnel, police strength, the use of GIS, population, being located in the Northeast and West regions, poverty, having encouraged SARA type projects and a community policing unit.
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Étude éco-épidémiologique sur l’infection par Francisella tularensis au QuébecGabriele-Rivet, Vanessa 12 1900 (has links)
Au Canada, Francisella tularensis, une bactérie zoonotique causant la tularémie, affecte principalement le lièvre d’Amérique, le rat musqué et le castor. Malgré les nombreuses études sur cette maladie, les connaissances sur l’écologie et les réservoirs naturels de la tularémie demeurent limitées. Une étude transversale a été réalisée afin d’estimer la prévalence d’infection par F. tularensis chez le lièvre d’Amérique, le rat musqué et le coyote dans quatre régions du Québec (Canada) et de décrire le risque d’infection d’après des caractéristiques individuelles (âge, sexe et état de chair) et environnementales. D’octobre 2012 à avril 2013, 345 lièvres d’Amérique, 411 rats musqués et 385 coyotes capturés par des trappeurs ont été échantillonnés. Les caractéristiques environnementales autour du site de capture ont été extraites de base de données géographiques. La séroprévalence (test de microagglutination) était de 2.9% chez les coyotes, 0.6% chez les lièvres et 0% chez les rats musqués. Tous les rats musqués et les lièvres étaient négatifs à une PCR en temps réel réalisée à partir d’un pool de foie, rein, rate et poumon; par contre, le type AI a été détecté dans les organes individuels des deux lièvres séropositifs. Des analyses de régression logistique exacte ont démontré que l’âge était un facteur de risque pour la séropositivité du coyote, ainsi que la proportion de forêts et la proportion de l’environnement considéré approprié pour le lièvre autour de la localisation de capture des coyotes. Les résultats de cette étude suggèrent la présence du cycle terrestre dans les régions étudiées. / In Canada, Francisella tularensis, the zoonotic bacterial agent of tularemia, affects mostly snowshoe hares, muskrats and beavers. Despite numerous studies, knowledge of its ecological occurrence and natural reservoirs is limited. A cross-sectional study was conducted to estimate the prevalence of F. tularensis in snowshoe hares, muskrats and coyotes in four regions of Québec, Canada, and to describe the risk of infection in relation to individual host (age, sex and body condition) and environmental characteristics. Between October 2012 and April 2013, 345 snowshoe hares, 411 muskrats and 385 coyotes were captured by trappers. Ecological characteristics of the location of capture were extracted from geographical databases. Prevalence of antibodies against F. tularensis (microagglutination test) was 2.9% in coyotes, 0.6% in hares and 0% in muskrats. F. tularensis DNA was not detected by real-time PCR in the pools of liver, kidney, lung and spleen from muskrats and hares but F. tularensis type AI was detected during testing of individual organs of two seropositive hares. Exact logistic regression analyses showed that age was a significant risk factor for seropositivity of coyotes, as were the proportion of forest and the proportion of area considered suitable for hares in the environment around the location of capture of the coyotes. The results of this study suggest the presence of the terrestrial cycle of F. tularensis in the regions studied.
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Využití a výběr monitorovacího systému ve speciální tělesné přípravě AČR / Use and selection of monitoring system in special physical training of Army of the Czech RepublicRaděj, Karel January 2012 (has links)
AABBSSTTRRAACCTT TTiitteell:: Use and selection of monitoring system in special physical training of Army of the Czech Republic GGooaallss:: The goal of this thesis is to give a complex, integrated and comprehensive overview about functional options and effective utilization of Monitoring System in selected areas of special physical training of Czech Army. MMeetthhooddss:: Study, analysis, synthesis and comparison of published findings of professionals from the fields of Geography, Geodesy and Special Physical Training were used in this thesis. Secondary research consisted of interviews with experts on mentioned areas and disciplines. RReessuullttss:: The main subject of this work is the utilization of Monitoring System in special physical training process. Usage of MS in selected areas of special physical training will result in effective support in terms of planning, safety and overall evaluation of its individual parts. KKeeyy wwoorrddss:: GNSS (Global Navigation Satellite System) GPS (Global Positioning System) GIS (Geographic Information System) Special physical training Load Monitoring system Date
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[en] LOCATING PUBLIC FACILITIES: STUDY CASE OF CATHOLIC CHURCHES IN BARRA DA TIJUCA AND RECREIO DOS BANDEIRANTES, RIO DE JANEIRO / [pt] LOCALIZAÇÃO DE EQUIPAMENTOS PÚBLICOS: ESTUDO DE CASO DOS TEMPLOS CATÓLICOS NA BARRA DA TIJUCA E RECREIO DOS BANDEIRANTES, RIO DE JANEIROCLAUDIO AMARANTE DE ALMEIDA MAGALHAES 22 July 2014 (has links)
[pt] Esta dissertação examina o problema da localização de uma rede de equipamentos públicos. O estudo aborda as etapas de modelagem do problema, concepção e correção da base de dados, utilização de funções geográficas, monitoramento dos resultados e comparação das soluções obtidas por diversos algoritmos. O objetivo do estudo é determinar a localização dos equipamentos, de forma que o somatório das distâncias percorridas por seus usuários seja mínima, ou seja, o objetivo é minimizar a inconveniência coletiva dos usuários, a qual é medida pelo produto do número de usuários vezes a menor distância ao equipamento mais próximo. O trabalho baseia-se em outros estudos propostos para localizar serviços de saúde, ensino, e atividades gerais de serviços, fundamentados no modelo da p-mediana, e resolvidos por métodos heurísticos e exatos. O estudo de caso abordou a localização dos templos católicos existentes na Barra da Tijuca e Recreio dos Bandeirantes, Rio de Janeiro, RJ. A circulação nesses bairros foi projetada, privilegiando o uso de automóvel em vias expressas, mas contrariando o conceito ambientalista de mobilidade. O estudo busca avaliar a atual localização da rede de templos, assim como avaliar a sua estabilidade, com o objetivo de minimizar a inconveniência coletiva. Além de avaliar a atual localização, o estudo estabelece o local ideal para adicionar um novo templo, bem como simular a alienação de uma unidade dentre as existentes. Para buscar as melhores alternativas foram usados métodos heurísticos tradicionais: o método Guloso e o de Maranzana, além de ser proposta uma nova metodologia heurística, e, igualmente, encontrada a solução ótima, que serviu de comparação. / [en] This Master’s thesis in Urban and Environmental Engineering, deals with the problem of locating a network of public facilities. This topic is certainly important whenever one strives for efficient and sustainable urban planning. As in any large city, the location of a public facility affects the movement of people, transportation flows, infrastructure distribution, product logistics and waste management, among other activities. Such topic grows in importance when the study is directed to urban settings facing large growth rates and which demand constant changes in the equipment network. This is the case of most large Brazilian cities that continue to undergo significant density increases resulting from real estate speculation and internal migration. Therefore, the thesis’ theme draws upon several disciplines of the Urban and Environmental Engineering Program professional master’s program and meets its objectives.
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Multi-providers location based services for mobile-tourism : a use case for location and cartographic integrations on mobile devices / Services localisés multi-fournisseurs pour le tourisme mobile : un cas d'utilisation pour l'intégration sémantique et cartographique sur des dispositifs portablesKaram, Roula 26 September 2011 (has links)
Les services géolocalisés (LBS) sont destinés à délivrer de l’information adéquate aux utilisateurs quelque soit le temps et l’endroit et ceci en se basant sur leur profil, contexte et position géographique. A travers n’importe quelle application dans ce domaine, par exemple m-tourisme, les utilisateurs souhaitent toujours recevoir une réponse rapide et précise en se déplaçant. Cependant, la qualité de service proposée par les fournisseurs cartographiques actuels (i.e. Google Maps, Bing, Yahoo Maps, Mappy ou Via Michelin) dépend de leurs données géographiques. En général, ces données sont stockées de plusieurs bases de données géographiques (BDG) dans le monde entier. D’autre part, le nombre croissant des différentes BDG couvrant la même zone géographique et la récupération des données/métadonnées non erronées pour un service quelconque, impliquent de nombreux raisonnements et de contrôles d’accès aux BDG afin de résoudre les ambiguïtés dues à la présence des objets homologues dupliqués sur l’écran mobile. Mon travail consiste à permettre cette intégration cartographique pour les applications mtourisme et ceci en récupérant les informations spatiales/non-spatiales (noms, positions géographiques, catégorie du service, détails sémantiques et symboles cartographiques) de plusieurs fournisseurs. Cependant, ceci peut conduire à visualiser des objets dupliqués pour le même point d’intérêt et causer des difficultés au niveau de la gestion des données. En outre, l’utilisateur sera dérouté par la présence de résultats multiples pour un même point. Donc, mon but ultime sera de générer automatiquement une carte unique intégrant plusieurs interfaces des fournisseurs sur laquelle les objets homologues seront intégrés avant de les visualiser sur l’écran mobile. Nos nouveaux concepts, basés sur certains algorithmes de fusion, sur l’ontologie pour assurer l’intégration au niveau sémantique et cartographique, sur l’orchestration des géo web services, sont implémentés dans des prototypes modulaires et évalués. / Through any location based services application (LBA) (i.e. m-tourism), users who request information while on the move, intentionally seek as well a quick and precise answer on any map. However, the quality of the cartographic search engines such as Google maps, Bing, Yahoo Maps, Mappy or Via Michelin relies on their geographic datasets. Typically, these datasets had been collected from many geographic databases worldwide. However, the increasing number of different GDBs covering the same area and the retrieval of accurate data/metadata for the requested service will imply lots of reasoning processes and databases’ accesses in order to avoid nearly-duplicated records when displayed on the screen. The scope of my research is to ensure location and cartographic integrations for m-tourism LBA by retrieving spatial/non-spatial information (place names, geographic positions,category type, semantic details and cartographic symbols) from many service providers.However, this will cause many nearly-duplicated records for the same datasets which would bring trouble to data management and make users confused by the different results of a unique query especially for the same point of interest. In other words, my ultimate goal is to generate automatically a unique map from multiple providers’ portrayals such as Google Maps, Bing and Yahoo Maps while homologous features should be integrated to avoid duplicate icons on the mobile screen. Our conceptual framework, based on some fusion algorithms, ontology reasoning for cartographic interoperability and geo-web services orchestration, had been implemented in some modular prototypes and tested for evaluation purpose.
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