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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.
131

Predicting Infestations of Hemlock Woolly Adelgid ( <em>Adelges tsugae</em> ) in Great Smoky Mountains National Park, Tennessee/North Carolina, USA

Snider, Scott January 2004 (has links)
No description available.
132

Kommunal samverkan inom GIS : En undersökning av Västerbottens och Norrbottens kommuner

Ekeståhl Unger, Clara-Elin January 2024 (has links)
The aim of this paper is to examine GIS in municipalities within Norrbotten and Västerbotten. This involves examining the GIS use in the municipalities. It also involves an investigation of how cooperation between the municipalities works and could develop in the future. This study is based on the NorrGIS inventory of GIS from 2021. This paper is based on a quantitative research method with a questionnaire that has been sent out to representatives within the GIS operations in the municipalities. Competence and resources within GIS are limited within the municipalities which may be based on size and resource assets. GIS use differs between municipalities and many of the GIS operations within the municipalities need to be improved. A major problem is that the competence within the municipalities is not sufficient. There is also cooperation within GIS tools and many of the municipalities have GeoSecma as the main tool. Furthermore, GIS collaboration is needed to use GIS full potential. A collaboration may be a necessity for smaller municipalities to overcome obstacles that GIS use entails. A large part of the obstacles for GIS lies at the political level, which can be a difficult challenge to manage. Human resources and technical resources are considered affordable, the problem lies in how decision-makers choose to allocate resources. The political level places limitations on possible cooperation. Despite limitations in both political ambition and competence, the result displays a need for collaboration within the municipalities. Another problem is the responsibility for cooperation. Who has the final responsibility for GIS-collaboration to function optimally?
133

Modeling and Assessment of State-Of-The-Art Traffic Control Subsystems

Mladenovic, Milos Novica 12 May 2011 (has links)
Traffic signals are one of the vital control elements of traffic management and control systems under purview of Departments of Transportation (DOTs) nationwide. They directly affect mobility, safety, and environmental parameters of the transportation networks. Traffic engineers in DOTs often face pressure for extracting additional benefits from existing signal control equipment, influenced by evident increase in demand and changing traffic patterns. However, they often face difficulties, usually from the maturity of the field equipment, lack of understanding of currently available equipment capabilities, and multitude of market available equipment. Besides issues in everyday operation, the need for improved decision-making process appears during selection and implementation of the future signal-control subsystems. This thesis is focusing on the issues related with the need for extracting additional benefits and improved planning of signal-control equipment deployment. Presented are several methodologies and techniques for modeling and assessing traffic signal controllers and supporting communication infrastructure. Techniques presented in this thesis include Petri Net modeling language, Software-in-the-loop simulation, and Geographical Information Systems. Specific capabilities of listed techniques are coordinated for maximizing their benefits in addressing specific issues. The intended positive effects reflect in enhanced comprehension, numerical representation, and analysis of state-of-the-art signal control subsystems in focus. Frameworks, methodologies, and example cases are presented for each of the specific issues in identified traffic signal subsystems, along with recommendations for further research. / Master of Science
134

Geographical Information Technologies – Decision Support for Road Maintenance in Uganda

Kayondo-Ndandiko, Lydia Mazzi January 2012 (has links)
This study set out to develop a framework within which the use of Geographical Information Technologies (GITs) can be enhanced in Road Infrastructure Maintenance (RIM) in Uganda. Specifically it was guided by 3 objectives; 1. To assess the gaps in the use of GITs for RIM in Uganda and the limitations to accessing these technologies, 2. To develop a methodological framework to enhance the use of GITs in RIM and 3. To develop a Geographical Information Systems for Transportation (GIS-T) data model based on the road maintenance data requirements. A participatory approach through a series of interviews, focus group discussions, workshop &amp; conferences, document reviews, field observations &amp; measurements and GIS analysis were employed. Based on the Spatial Data Infrastructure (SDI) concept and the principle of Causality, the gaps and limitations were established to mainly be concerned with data and organisational constraints as opposed to technical issues. They were classified to include; inadequate involvement of GITs in organisational activities, inappropriate institutional arrangements, absence of data sharing frameworks, budget constraints, insufficient geospatial capacity, digital divide in the perception, adoption &amp; affordability of GITs among the stakeholders and the absence of a road maintenance Spatial Data Infrastructure (SDI). A methodological framework, comprising of 6 strategic components was developed to enhance the use of GITs in RIM. This included enactment of relevant policy components to guide GIT use, continuous capacity building, establishment of a road maintenance SDI, fostering collaboration and spatial data sharing frameworks, budgetary allocation based on defined activities inclusive of GIT initiatives, and adoption of a dynamic segmentation data model. Conceptual and logical data models were developed and proposed for the Sector. The conceptual model, presented using an entity relationship diagram, relates the road network to the point and line events occurring on it. The logical object relational model developed using the ESRI provided template represents the road and the point and line events in a total of 19 object classes. The Study concludes that in order to ground GIT benefits in the sector; technical, data and organisational concerns involved in GIT undertakings should be accorded equal emphasis. Institutionalisation and diffusion of GITs as aspects of the component strategies are regarded capacity building mechanisms earmarked to boost success in GIT initiatives. Further research on diffusion and funding models for GIT initiatives is recommended. It is suggested that aspects of the proposed model be considered when establishing GIT standards for the sector. The RIM sector is encouraged to embrace Science and Technology and to participate in Research and Development and particularly to adopt the culture of innovation considering the ready availability of off the shelf equipment, freeware and open source software that can foster informed decision making.
135

Tillämpning av GIS-analyser i MKB / Application of GIS-analyses in EIA

Wall, Erik January 2006 (has links)
<p>The reason for performing an Environmental Impact Assessment (EIA) is to incorporate environmental concern in different kinds of plans and projects. The purpose of such an assessment is to identify and describe direct, indirect and cumulative environmental impacts.</p><p>Geographical Information System (GIS) is a tool that can be used to combine spatial extension of both sensitive areas and different environmental impacts in a quick and easy way. Because of that, descriptions of environmental impacts and motivation of different standpoints on a specific issue can be more correct and easier to make if GIS is used as a tool.</p><p>Hence, GIS can contribute to improve the quality of Environmental Impact Assessments. If the benefits of using GIS are to out weight the costs, geographical information of satisfactory detail, actuality and accuracy need to be available at reasonable prices.</p><p>In this paper, case studies are carried out for three different geographical analyses to investigate the use of GIS as a tool in EIA. From these case studies, more general conclusions about the benefits and limitations of using GIS for Environmental Impact Assessments are also drawn. The criteria, after which benefits and limitations of GIS have been estimated, are data availability, time consumption for performing the analyses and how the results from the performed analyses can make impact assessments easier, motivate different standpoints and increase the comprehensiveness of the EIA-report.</p><p>The three different GIS-analyses includes calculation of pollution load in a catchment area, estimation of the visual impact from planned buildings and generation of alternative locations for underwater pipes. These analyses have been applied on one ongoing EIA for a freight terminal and one ongoing EIA for an underwater wastewater transmission pipe. The analyses in these case studies have been undertaken with ArcGIS software using the extensions “Spatial Analyst” and “3D Analyst”.</p><p>It is shown in this study that due to uncertainty in available model values and the time consuming data manipulation, it is unlikely that calculations of pollution loads with GIS will be used to any larger extent in EIA. To carry out visual assessments with help of GIS to estimate visual impacts is on the other hand assumed to be useful in EIA-work. Both to assess impacts and to estimate how changes in building design can alter those impacts. To use GIS to produce alternative locations for underwater pipes is also considered valuable in EIA-work, even though there is a considerable lack of data to predict the environmental class of marine areas and the connections between available data and real environmental values are weak. However, the risk of damaging vulnerable and high valued marine areas should decrease when applying this type of analyse.</p> / <p>Miljökonsekvensbeskrivningar (MKB) genomförs för att möjliggöra att hänsyn om miljön tas vid olika typer av exploateringsprojekt och exploateringsplaner. Syftet med en miljökonsekvensbeskrivning är att identifiera och beskriva direkta, indirekta och kumulativa miljöeffekter.</p><p>Geografiska informationssystem (GIS) är ett verktyg som kan användas för att snabbt och enkelt kombinera rumslig utsträckning av både känsliga områden och olika miljökonsekvenser. GIS kan därför användas för att underlätta beskrivningar av miljökonsekvenser och motivera olika ställningstaganden. Därigenom kan GIS bidra till bättre grundade och mer rättvisande miljökonsekvensbeskrivningar. Men för att vinsterna av att genomföra GIS-analyser ska överstiga kostnaderna krävs att geografisk information av tillräcklig detaljeringsgrad, aktualitet och säkerhet finns att tillgå till rimliga kostnader.</p><p>Syftet med denna studie har varit att genom fallstudier undersöka om tre olika GIS-analyser kan användas som verktyg i miljöbedömningar med idag tillgänglig data, samt att utifrån fallstudierna dra mer allmänna slutsatser om vinster och begränsningar av att använda GIS i miljökonsekvensbeskrivningar. De kriterier som har använts för att bedöma vinster och begränsningar är tidsåtgång för analyserna, tillgång på data samt hur analyserna kan vara ett stöd i MKB-arbetet genom att underlätta beskrivningar av konsekvenser, motivera ställningstaganden som görs och öka rapportens begriplighet.</p><p>De tre genomförda GIS-analyserna innefattar beräkning av föroreningsbelastning inom ett avrinningsområde, bedömning av byggnaders landskapspåverkan genom synlighetsanalys samt generering av förslag till alternativ ledningsdragning för en undervattensledning. Dessa analyser har tillämpats på en pågående MKB för en detaljplan för en partihall och en pågående MKB för en avloppsvattenledning under vatten. Analyserna i fallstudierna har genomförts i programmet ArcGIS med tilläggen ”Spatial Analyst” och ”3D Analyst”.</p><p>Studien visar att det på grund av osäkerheter i tillgängliga schablonvärden och tidsåtgång för databehandling är osannolikt att beräkning av föroreningsmängd inom ett avrinningsområde med GIS kommer att användas till någon större utsträckning i MKB. Att med GIS genomföra synlighetsanalyser för att utvärdera landskapspåverkan bedöms däremot kunna användas i MKB, både för att bedöma påverkan och för att utvärdera hur en förändring i en byggnads utformning kan förändra den påverkan. Även att med GIS generera förslag till alternativa ledningsdragningar under vatten bedöms kunna fylla en funktion i MKB trots att tillgången på data för att kunna beskriva olika marina områdens naturvärden är klart bristfällig och kopplingen mellan tillgängliga data och verkliga naturvärden är osäker. Denna typ av analys bör ändå minska risken att värdefulla och skyddsvärda marina områden skadas vid lednignsdragning.</p>
136

Localication et cartographie simultanées par vision monoculaire contraintes par un SIG : application à la géolocalisation d'un véhicule / Monocular SLAM contrained with GIS data and its Application to vision-based Vehicle Geo-localization

Lothe, Pierre 08 October 2010 (has links)
Les travaux réalisés au cours de cette thèse s’inscrivent dans les problématiques de localisation d’un véhicule par vision. Nous nous plaçons en particulier dans le cas de parcours sur de longues distances, c’est à dire plusieurs kilomètres. Les méthodes actuelles de localisation et cartographie simultanées souffrent de problèmes de dérives qui les rendent difficilement exploitables après plusieurs centaines de mètres. Nous proposons dans ce mémoire de pallier ces limites en exploitant une connaissance à priori sur la géométrie de l’environnement parcouru.Cette information est extraite d’un Système d’Information Géographique. En particulier, les travaux réalisés se basent sur les modèles 3D des bâtiments des villes et sur une carte de la route.Dans la première partie de ce mémoire, nous proposons une approche permettant de corriger hors ligne une reconstruction SLAM en exploitant la connaissance d’un modèle 3D simple de l’environnement. Cette correction s’applique en deux étapes. En premier lieu, un recalage non-rigide entre le nuage de points reconstruit et le modèle 3D est effectué de sorte à retrouver la cohérence globale de la reconstruction. Dans le but de raffiner le nuage de points obtenu, un ajustement de faisceaux contraint par le SIG est alors effectué sur l’ensemble de la reconstruction.La particularité de cet ajustement de faisceaux est qu’il prend implicitement en compte les contraintes géométriques apportées par le modèle 3D. La reconstruction ainsi corrigée est alors utilisée en tant que base de données pour la relocalisation en ligne d’une caméra mobile. La précision de relocalisation obtenue est en particulier suffisante pour les applications de réalité augmentée.Dans la deuxième partie de ce mémoire, nous détaillons une solution permettant de corriger en ligne la reconstruction SLAM. Pour cela, les contraintes géométriques apportées par le SIG sont exploitées au fur et à mesure de la trajectoire du véhicule. Nous montrons tout d’abord que la connaissance de la position relative de la caméra par rapport à la route permet de corriger de façon robuste la dérive de facteur d’échelle. De plus, lorsque les contraintes géométriques sont suffisantes, la reconstruction SLAM réalisée jusqu’à l’instant courant est recalée sur le SIG.Cela permet de corriger ponctuellement la dérive observée sur la position courante de la caméra.Le processus complet permet dès lors de localiser le véhicule avec une précision semblable à celle d’un système GPS sur des trajectoires de plusieurs kilomètres.Les deux méthodes proposées ont été testées à la fois sur des séquences de synthèse et réelles. Des résultats qualitatifs et quantitatifs sont présentés tout au long de ce mémoire. / This thesis deals with the vision based geolocalisation of a vehicle. In particular, the problem of localisation on large sequences, i.e. several kilometers, is studied. In this context, state of the art Simultaneous Localisation and Mapping systems suffer from drift. In consequence,existing SLAM methods can not provide accurate localisation of the camera after several hundred meters. Thus, we propose in this thesis to avoid the drift phenomenon by exploiting a simple knowledge about the geometry of the environment. This information is provided by a Geographical Information System. In particular, our work is based on coarse 3D city models and road maps.In the first part, we propose an offline two steps correction of SLAM reconstructions based on a 3D city model of the area. First, the reconstructed 3D point cloud and this 3D city model are aligned through a non-rigid transformation. This step allows the SLAM reconstruction to regain its global consistency. Then, a bundle adjustment constrained with the GIS is applied on the entire reconstruction to refine its geometry. The innovation of this bundle adjustment is that it takes into account the geometrical constraints provided by the 3D city model in a single term.The obtained 3D point cloud can then be considered as a feature landmark database. Finally, this database is used to localise a moving camera in real-time. In pratice, the precision of the obtained localisation is sufficient for augmented reality applications. In the second part of this manuscript, we present a solution which makes possible the online correction of a SLAM reconstruction. The GIS geometrical constraints are exploited over the vehicle trajectory. First, we show that the scale factor drift can be robustly corrected thanks to the knowledge of the ground plane equation. Furthermore, the current SLAM reconstruction is fitted onto the GIS when the geometrical constraints are sufficient. It punctually ensures the correction of the current camera position. The entire process allows the geolocalisation of a vehicle on several kilometers. The obtained precision is close to GPS.The two proposed solutions have been validated of both synthetic and real sequences. Quantitative and qualitative experiments are presented over this manuscript.
137

Monitoramento e avaliação da qualidade da água na microbacia do córrego campestre no município de Lins-SP /

Cuelbas, Leandro Pereira. January 2007 (has links)
Orientador: Sérgio Luis de Carvalho / Banca: Edson Pereira Tangerino / Banca: Maria José Alencar Vilela / Resumo: O estudo foi realizado na microbacia do Córrego Campestre que está localizada no Município de Lins, Estado de São Paulo, compreendendo uma área de 80 km2. Nessa área está inserida a Cidade de Lins com uma área urbana de 20 km2, perfazendo 25% da microbacia em estudo. Através das coletas e análises de amostras de água, no período de seca e chuva, dos principais córregos da microbacia do Córrego Campestre, foi possível obter resultados do Índice de Qualidade da Água - ÍQA. Com bases nos resultados combinados, com as informações obtidas através das imagens de satélite e fotos dos locais, constatou-se que os efeitos das atividades antrópicas principais desenvolvidas na região urbana, a urbanização e lançamentos de resíduos nos cursos d'água sem nenhuma forma de tratamento, provocaram elevados teores de matéria orgânica e coliformes, comprovado através da analise das características físico-químicas e bacteriológicas. Constatou-se também, a partir das observações feitas "in loco", fortes evidências de degradação da microbacia, principalmente por um antigo lixão que está localizado às margens do Córrego Campestre. Através da analise das imagens de satélite, utilizando um Sistema de Informações Geográficas - SIG, foi possível identificar a inexistência de vegetação ciliar, o que contribuiu para o carregamento de resíduos poluentes do solo aos cursos d'água após as chuvas intensas. / Abstract: The study it was carried through in the microwatershed of the Campestre Stream that is located in the region of the Lins city, São Paulo State, understanding an area of 80 km 2. In this area the Lins city with an urban area of 20 is inserted km 2, with about 25% of the microwatershed in study. Through the collections and analyze chemistry of samples of water, in the drought periods and rain, of the main streams in the microwatershed of the Rural Stream, it was possible like this to obtain results of the Index of Quality of the Water - ÍQA and analyses of the parameters physical, chemical and biological. Those combined results with the information obtained through the satellite images and pictures of the places, it was verified that the effects of the activities main human actions developed in the urban area, the urbanization and releases of residues in the courses of water without any handling form, they provoked high tenors of organic matter, coliformes and nutritious, proven through it analyzes it of the physiochemical and bacteriological characteristics. It was also verified, starting from the observations done " in loco ", strong evidences of degradation of the microwatershed mainly for an old deposit garbage that is located to the margins of the Rural Stream. Through it analyzes her/it of the satellite images, being used... (Complete abstract click electronic access below) / Mestre
138

Diagnóstico da condição tecnológica, sob a ótica da qualidade, das operações mecanizadas da cultura do trigo em sistema plantio direto. / Diagnosis of the technological condition, under the quality view, of mechanized operations of wheat crop in no-tillage system.

Suguisawa, Jorge Murilo 25 June 2004 (has links)
Tendo-se em conta a importância da lavoura tritícola para o país, e que o aumento da produtividade depende também da correta execução das operações de implantação e condução da cultura, este trabalho tem como objetivo avaliar a estabilidade dos processos de produção e ao atendimento aos padrões especificados de um sistema de plantio direto na cultura do trigo. Os dados foram coletados em um talhão da Fazenda Paiquerê, do Grupo Lúcio Miranda, no município de Piraí do Sul, Estado do Paraná. Foram consideradas seis operações do processo produtivo do trigo sob sistema plantio direto: colheita da cultura antecessora, pulverização pré-semeadura, semeadura, adubação de cobertura, pulverização para tratamento fitossanitário e colheita do trigo. Para a avaliação do sistema produtivo em questão, foram determinados, para cada operação considerada, indicadores de desempenho e limites de especificação para cada indicador. Foram utilizados para a avaliação dos resultados, ferramentas de análise estatística descritiva, de controle da qualidade e do SIG. Pode-se concluir que o sistema de plantio direto de trigo considerado neste estudo não atendeu aos padrões especificados, necessitando de melhorias em todas as operações envolvidas no processo. A utilização das cartas de controle, do histograma e do SIG identificou os pontos que apresentaram problemas e que não se encontravam dentro das especificações agronômicas em todas as operações avaliadas. O uso de técnicas geoestatísticas aliadas à tecnologia SIG permitiu o adequado zoneamento dos indicadores analisados, identificando áreas com diferentes quantidades. / Considering the relevance of wheat crop in Brazil, and that the yield increase depends also on the correct execution of implementation and management of the crop, this work aimed to evaluate how stable the production processes are and to the specified patterns attending of a no-tillage wheat crop. The data were collected at Paiquerê farm, belonged to Lúcio Miranda Group, in of Piraí do Sul city, Paraná state. Six operations of the production process of the no-tillage wheat were considered: harvesting of the former crop, spraying before drilling, drilling, fertilizer spreading, spraying and wheat harvesting. To evaluate the studied production system, it were determined to each considered operation, performance indicators and specification limits to each indicator. Tools of descriptive statistics analysis, of quality control and GIS were used. It was concluded that the evaluated system did not attend the specified patterns, needing improvements in all operations involved in the process. The utilization of control charts, histogram and GIS identified where there were problems and that were not in the agronomic specification range in all the evaluated operations. The use of geostatistical techniques together GIS technology allowed the adequate zoning of the studied indicators, identifying areas with distinct quantities.
139

Planejamento da execução de remendos em vias urbanas sob o enfoque da logística de serviços / Planning pathings services in urban pavements with service logistics

Massaro, Leonardo Curval 09 December 2005 (has links)
O objetivo deste trabalho é apresentar os conceitos da logística, em especial a logística de serviços, e algumas de suas ferramentas, como a roteirização de veículos e previsão de demanda por serviços, aplicadas aos serviços urbanos, neste caso o serviço de remendos em pavimentos, visando aumentar a eficiência desse serviço. O serviço de remendos, muitas vezes chamado de tapa-buracos, é uma atividade de manutenção comum nas cidades. Para observar a aplicação das ferramentas foi elaborado um estudo de caso na cidade de São Carlos. Dados sobre o serviço de remendos em pavimentos foram coletados e, com a ajuda de um sistema de informações geográficas – SIG, foram gerados roteiros que foram comparados com os dados originais. As rotas simuladas pelo SIG foram mais eficientes do que as praticadas na realidade, mostrando a utilidade dos conceitos da logística e também a utilidade do SIG na gerência da infra-estrutura urbana. A previsão de demanda por serviços de remendos não pôde ser observada devido à falta de dados históricos, fundamentais a essa etapa do trabalho. / The objective of this work is to introduce the concepts of logistics, especially the service logistics and some of its tools as the vehicle routing and the demand forecast for services, applied to the urban services, in this case the patching service in pavements in order to increase the efficiency of this service. The patching service, many times called tapa-buracos (in Brazil), is a common activity of maintenance in the cities. To observe the application of the tools one case study was elaborated in the city of São Carlos. Data about the patching service in pavements were collected and, helped by the geographic information system – GIS, routes were created and compared to the original data. The paths simulated by the GIS were more efficient than the real ones, showing the utility of the logistics concepts and also the utility of the GIS on the management of the urban infrastructure. The demand forecast for services of patching could not be observed due of the lack of historical data, essential to this part of the work.
140

Estudo da verticalização no bairro Jardim Anália Franco no município de São Paulo: o uso do SIG como apoio a análise espacial / Study of verticalization in Jardim Anália Franco in São Paulo: the use of GIS to support spatial analyses

Zichelle, Rodrigo 15 February 2011 (has links)
O processo de verticalização do bairro Jardim Anália Franco apresenta-se como marco de modernidade da cidade, fruto do avanço técnico-científico e da capacidade de mobilização de vários atores sociais. No entanto, através da análise empírica de tal processo, verifica-se que sua materialidade no espaço pode se apresentar como vetor de fragmentação do território. O SIG, com seus modernos recursos de sensoriamento remoto, oferece possibilidade de estudo sistemático de tal fenômeno. Acredita-se que, a partir da cartografia, possa-se analisar configurações espaciais que apoiarão futuros estudos no campo da geografia urbana. / The verticalization process of Jardim Anália Franco neighborhood present itself as a mark of the modenity of the city, product from de technical advance and capacity of mobilization from many social actors. However, through the empirical analysis of that process, it appears that its materiality in space can be presented as vector of the territory. The GIS, with its modern resources of remote sensing, offers possibility of systematic study of this phenomenon. Its believed that, from the mapping, can be examined spatial configurations that will support future studies in the field of urban geography.

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