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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

Geographical Information System (GIS) web applications for data visualization of Drinking Water pipelines

Shekhawat, Pururajsingh 08 August 2018 (has links)
Robust decision support tools that aid water utilities to make informed, swift and precise decisions are becoming the need of the hour. Application of sophisticated models to aid the process of condition assessment and risk analysis on water pipelines have been limited owing to the lack of scalability, inability to incorporate external open source datasets and mathematically complicated output results. Interactive visualization of resultant model output is the key element in extracting valuable information to support decision making. This thesis presents a framework for visualization of data related to drinking water pipelines. Critical components of strategic, tactical and operational level decision making are explored in context with data presentation and information depiction. This thesis depicts various aspects of developing GIS web applications and their important functionalities for query and visualization of data. Multiple facets of data storage, standardization and application development are highlighted in this document. Publishing of application geo processing services in web environment is done through Virginia Tech enterprise geodatabase. Risk assessment and Performance models developed by a utility are projected in the application environment through help of widgets. Applications are coded into links on a Drupal website (www.pipeid.org) for model dissemination and utility engagement purposes. / Master of Science / Drinking water supply network primarily consists of pipelines, pumping stations, reservoir basins and treatment plants. Water pipelines are routinely inspected to check their condition and maintain appropriate water quality. Management of these subsurface assets should be given prime importance for maintaining high standards of services at acceptable cost to customers. An integral step in accomplishing this task is to view pipeline network in a geographic map. Different factors affecting pipeline condition are displayed on the map in the form of individual layers. Such real-world problems are analyzed with the help of Geographical Information System (GIS) tools that incorporate spatial features with tabular information. Moreover, interpretation of raw data into meaningful insights and distribution of allocated knowledge to all the concerned parties can be efficiently accomplished using rich internet applications. This thesis presents a framework to use GIS tools for developing web applications using raw data samples from contacted water utilities. Sample web applications are created and discussed in the form of case studies. Also, the challenges in water utility sector with respect to utilizing GIS tools for supporting daily decision-making processes is highlighted in this document. The recommendation to improve the suggested framework and adding more functionalities to developed applications are presented at the end with references.
22

Mellan älvor och offerblod : En undersökning om skålgroparnas uppkomst och betydelse i det fornnordiska landskapet / Between Fairies and Sacrificial blood : An investigation about the Origin and Purpose of the Cup Marks in the Norse Landscape

Jansson, Jenny January 2018 (has links)
The cup marks are the most common form of rock art in Scandinavia and they have been dated from the Mesolithic to the Migration period. In Sweden they are mostly found in the southern parts of the country. They are believed to generally have been made by permanently resident agrarian people from the Bronze age. The question about the cup marks origin and purpose is one of the unanswered questions in Scandinavian rock art research, which this essay has had the goal to answer with a holistic, statistical analysis based on all the registered cup marks in Sweden. Furthermore, the cup marks have been investigated in correlation with other ancient remains to see if there are patterns in the landscape that could indicate the cup marks purpose. The analysis confirmed that most of the cup marks probably where made by a permanent resident agrarian people on land mostly close to water, and that there seems to have been central places in the south of Sweden where different ancient remains have been made in clusters. No uniform meaning about the cup marks could be found with this method, but the research showed that with more detailed research about cup mark sites combined with a wider perspective about the entire cup marks placings in the landscape, new research will probably be able to get closer to an answer about the cup marks purpose and use in the Norse landscape.
23

Investigação de opções de transporte de carga geral em contêineres nas conexões com a região amazônica / Options investigation of the general cargo transport in containers in the connections with the amazon region

Teixeira, Karênina Martins 01 October 2007 (has links)
Comércio e indústria, atualmente, respondem por parcela significativa do produto interno bruto (PIB) do Brasil e juntos demandam significativa quantidade de transporte de carga, principalmente do tipo fracionada, fato que, nos últimos anos provocou o crescimento do transporte desse tipo de carga. O elevado crescimento industrial, em 2004 e 2005, nos principais estados da região norte do país, Amazonas e Pará, indicam o aumento potencial da demanda por transporte de carga fracionada entre o norte e o sudeste, que concentra o maior mercado consumidor. As grandes distâncias, entre o norte e o sudeste, fazem o custo de transporte ter grande impacto significativo no preço final das mercadorias. Esse fato levou à procura por opções de transporte de menor custo, para tornar os produtos fabricados na região norte mais competitivos no mercado interno. Atualmente, existe predominância do transporte rodoviário no corredor norte-sudeste, o que desperdiça, por hipótese, o potencial de outros modos de transporte, como cabotagem, transporte fluvial e, futuramente, transporte ferroviário (Ferrovia Norte-Sul e Ferronorte). Isso motivou o desenvolvimento desta pesquisa, que tem como objetivo avaliar opções de transporte intermodal, econômica e operacionalmente mais atraentes que as praticadas hoje no transporte de carga geral fracionada (produtos e insumos industrializados) em conexões com a região amazônica. A metodologia empregada no trabalho utilizou: (1) técnica de construção de cenários; (2) modelos de custo de transporte para os modos rodoviário, ferroviário, marítimo e fluvial; e (3) sistema de informação geográfica. Os resultados obtidos nesta tese indicam que opções de rotas rodo-marítimas e rodo-fluviais apresentam significativas reduções no custo total de transporte com relação às rotas preferenciais, hoje, praticadas para as ligações entre Belém-São Paulo e Manaus-São Paulo. Os resultados mostram, também, não haver perspectivas para o transporte rodo-ferroviário e rodo-fluvial-ferroviário nessas ligações, uma vez que, neste caso, o custo obtido é maior que os das rotas hoje praticadas. / Nowadays, business and industry are responsible for a significant portion of the GDP (Gross Domestic Product) in Brazil, and together they require a considerable amount of freight transport, mainly break-bulk cargo which has stimulated the transport growth of this kind of cargo. The enormous industrial growth in the most important states of the northern region of the country in the years 2004 and 2005 indicate the potential increase of break-bulk cargo transport between the north and the southeast, area that concentrates the strongest consumer market in the country. Due to the long distance between the country\'s north and southeastern regions, the cost of transport increases the final cost of the goods. This fact led to the search for lower cost transport options in order to make the products of that region more competitive in the domestic market. Currently there has been predominance of road transport in the north/southeast corridor wasting, hypothetically, the potential of other means of transport such as cabotage, river, and, in the future, railroad transport (Norte-Sul and Ferronorte railways). All of this brought about the development of this research which aims at evaluating the intermodal transport options that are economically and operationally more attractive than the break-bulk cargo transport (industrial input and products) used today in the connections with the amazon region. The methodology involves: (1) scenario building; (2) transport cost models for the road, railroad, and marine means; and (3) geographic information system. The results demonstrate that the route options road-marine and road-river show substantial reduction in the transport total cost when compared to the most popular routes used between Belém-São Paulo and Manaus-São Paulo. The results also reveal that there is no perspective of the use of road-rail and road-river-rail transport in such connections since the cost is higher than in the routes used nowadays.
24

The Contribution Of Geographic Information System To The Urban Planning Process In Turkey

Kepoglu, Volkan Osman 01 September 2003 (has links) (PDF)
This thesis attempts to show the contribution of Geographic Information System to urban planning process in Turkey. GIS can enhance the planning system by providing an access to accurate, reliable and update geographical information, producing alternatives according to the scenario and ensuring participation in the evaluation of the alternatives. This is the high level contribution of GIS for the enhancement of planning. The contribution can occur / if certain conditions are sustained such as establishment of geographical data provision system among public institutions. Obviously, these are connected with available technical and social infrastructure. Although, there is not a digital infrastructure system among the public institutions, several general directorates have started to provide some geographical information in their works. These efforts should be increased in quality and quantity. From the planning point of view, we argue that these are not even at satisfying level to work with the GIS in the plan-making processes. To prove our argument, the use of GIS and technology in the Bank of Provinces and private planning offices are inquired. The results of the thesis study show that the Bank of Provinces is in the transition period for the use of GIS. Private planning offices are in the initial stage and some of them seem unable to adopt themselves if the plan-making process becomes digital, because of the extra costs for them. Therefore, geographical data provision policies among public planning institutions will determine the future development of GIS in the planning process.
25

A geographic information system application to visualize and manage data

Wurtz, Joshua January 1900 (has links)
Master of Science / Department of Computing and Information Sciences / Scott A. DeLoach / A geographic information system (GIS) allows an individual to map, model, query, and analyze large quantities of data from a database according to their spatial locations. This project uses the ArcGis Java software Development Kit (SDK) to visualize, manipulate, and comprehend large amounts of publicly available information relevant to a spatial location. The application developed uses a graphical user interface to examine the public data of Riley County, Kansas. The user is able to load shapefiles through the interface and then examine the many spatial locations. By examining a spatial location the user is able to view the associated attribute information, manipulate it, and add additional attributes. Beyond viewing information at selected geometric locations, a user can also query the layer(s) to return the spatial locations that fit the query. These abilities can allow a user to understand and visualize patterns that they would not have been able to easily see from looking at the raw data. Increasing users' understanding of the environment they are working with improves their likelihood of success in their desired objectives.
26

Η χρήση των Γεωγραφικών Συστημάτων Πληροφοριών στην κατασκευή βάσης υδρογεωλογικών δεδομένων

Κουζέλη, Ευλαμπία 09 January 2014 (has links)
Η εργασία αυτή εκπονήθηκε στα πλαίσια του Μεταπτυχιακού Προγράμματος Σπουδών «Εφαρμοσμένη και Περιβαλλοντική Γεωλογία και Γεωφυσική». Αντικείμενο της εργασίας είναι η εφαρμογή των Γεωγραφικών Συστημάτων Πληροφοριών στο σχεδιασμό μιας Γεωγραφικής Βάσης Υδρογεωλογικών δεδομένων με εφαρμογή στο νομό Αιτωλοακαρνανίας. Η βάση αυτή θα αποτελέσει ένα εργαλείο με το οποίο θα γίνεται η διαχείριση μεγάλου όγκου υδρογεωλογικών πληροφοριών (στάθμες, στοιχεία ποιότητας των νερών κ.α.) με τρόπο απλό και γρήγορο. Τα πρώτο στάδιο της εργασίας ήταν ο καθορισμός των στόχων που έπρεπε να επιτευχθούν μέσω αυτής για τη σωστή δημιουργία της γεωβάσης. Το επόμενο βήμα έρχεται να γίνει με τη συλλογή των δεδομένων που θα τοποθετηθούν στη βάση αυτή. Οι πληροφορίες αυτές προέρχονται από εγκεκριμένες τεχνικές μελέτες που δόθηκαν από δημόσιες υπηρεσίες, ιδιώτες ή ήταν ανηρτημένες σε επίσημες κυβερνητικές ιστοσελίδες. Τα στοιχεία αυτά ήταν τόσο χωρικά (διοικητικά όρια νομών, υδρολογικές λεκάνες κ.α.) όσο και μη - χωρικά (περιγραφικές πληροφορίες όπως πληθυσμιακά δεδομένα ονομασία ή κωδικοποίηση λεκανών, υδροχημικές μετρήσεις κ.α.). Κάποια στοιχεία αποκτήθηκαν από την επί τόπου έρευνα που έγινε στα πλαίσια αυτής της εργασίας σε ένα κομμάτι της υδρολογικής λεκάνης της λίμνης Τριχωνίδας. Στη συνέχεια δημιουργείται η βάση χωρικών δεδομένων. Για να επιτευχθεί αυτός ο στόχος έπρεπε τα συλλεγμένα δεδομένα να ταξινομηθούν σε διαφορετικούς φακέλους ανάλογα με τις κοινές ιδιότητες που έχουν καθώς και σε διαφορετικό είδος αρχείων, ανάλογα με την επιθυμητή χρήση τους. Ακολουθεί, σε ένα μέρος αυτών, η δημιουργία υπέρ – συνδέσεων οι οποίες έχουν ως στόχο την άμεση πρόσβαση σε πίνακες βροχομετρικών και χημικών δεδομένων. Έπειτα με τη βοήθεια της γλώσσας SQL έχουν τεθεί ερωτήματα (queries) που οδηγούν στην ανάκτηση δεδομένων. Τέλος, δεν πρέπει να παραλείψουμε και το κομμάτι της επεξεργασίας μέρους των δεδομένων για την παραγωγή χαρτών και διαγραμμάτων. Αυτό πραγματοποιήθηκε τη βοήθεια εργαλείων του ArcMap. Σημαντικό είναι και το γεγονός ότι για τη δημιουργία των χαρτών έγινε χρήση διαφόρων μεθόδων ώστε να έχουμε τη δυνατότητα σύγκρισης των αποτελεσμάτων για την ορθή διεξαγωγή συμπερασμάτων. Η κατασκευή της βάσης αυτής είχε ως αποτέλεσμα την αποθήκευση ενός μεγάλου όγκου δεδομένων που είναι ταξινομημένα σε διαφορετικά επίπεδα και την παραγωγή χαρτών που καλύπτουν ένα μεγάλο εύρος των προαναφερθέντων θεματικών επιπέδων. / This project was produced within the Post-graduate studies program “Applied and Environmental Geology and Geophysics”. Object of this work is the application of Geographic Information Systems in designing a geographic hydro-geological data base with application to the Aitoloakarnania district. This data base will be used as a tool with which we will be able to manage a vast amount of hydro-geological information (elevation, water quality data etc.) in a very simple and fast way. The first stage of the study was to define the objectives to be achieved through this, for the proper creation of the geo-database. The next step was the collection of the data that would be added in this data base. This information came from approved technical studies provided by public services, individuals or was posted on official governmental websites. These elements were spatial (administrative district boundaries, basins, etc.) and also aspatial (descriptive information such as demographic data, basins names or codes, hydro-chemical measurements, etc). Some other elements were obtained by in - situ investigation, conducted for this project at a part of the hydrological basin of Trichonida lake. Next the spatial data base was produced. In order to achieve this we had to put the collected data in different folders according to their common properties and in different file types according to their desired use. Then a part of these files were used to make hyper- links whose objective was to give direct access to tables of precipitation and chemical data. With the SQL, various queries have been set in order to lead to the data retrieval. Finally, we must not omit the process of a part of the data for the production of maps and diagrams for which we used the ArcMap tools. An important fact is that for the production of these maps, we used various methods so that we can have the possibility to compare the results and make correct conclusions. The results of this data base production are, the storage of a vast quantity of data that is classified in different levels and the production of maps that cover a big part of all the above mentioned thematic levels.
27

Internet GIS as a Historic Place-Making Tool for Mammoth Cave National Park

Epperson, Ann E. 01 December 2010 (has links)
This project laid the groundwork for an Internet-delivered Public Participation Geographic Information System to facilitate exploration and discovery of the past communities of the Mammoth Cave Park area. The emergence of Internet Web 2.0 design along with distributed GIS services allows for anyone to interact with and add to the information found on central Internet sites. Historical geography often relies upon public participation from individuals outside the academic world to provide narrative descriptions, photographs and manuscripts of past places and events to augment information held by institutions and academia. A public-participation website for the Mammoth Cave Historic GIS (MCHGIS) created a central Internet location for dispersed and disparate data related to pre-park communities to be presented with a geographic context. The MCHGIS project allowed for visualization of the pre-park communities in unique ways and contributed new understandings of this pre-park area.
28

Air pollution and health: distribution and determinants of exposure in Montreal, Quebec with a focus on polycyclic aromatic hydrocarbon assessment

Miao, QUN 30 July 2013 (has links)
Background: The International Agency for Research on Cancer has classified diesel exhaust as a carcinogen, and specific polycyclic aromatic hydrocarbons (PAHs) as probable carcinogens. Urban air pollution is one source of PAH exposure. These facts provided motivation to pursue three thesis objectives: 1) to critically review environmental inequity research in Canada and methods used in previous studies; 2) to determine associations between socio-demographic factors and residential traffic exposure; and, 3) to assess correlations between two PAH biomarkers and their relationship with a newer geographic information system (GIS) method (a proxy of PAH exposure measurement), and explore determinants of these two PAH biomarkers. Methods: The first objective was achieved through an extensive and critical literature review. The second and third objectives were achieved through conducting a cross-sectional study in Montreal where 107 female and 93 male volunteers completed a questionnaire and provided a urine sample for measurement of 1-hydroxypyrene (1-OHP) and 1-hydroxypyrene glucuronide (1-OHPG). GIS-based distance-weighted traffic density (DWTD) at participants’ residences and time- and distance-weighted traffic density (TDWTD) for all participants’ locations in the 48 hours before urine collection were calculated. Results: Participants with lower household income and unemployment/student status were more likely to be exposed to higher traffic density at their residence. DWTD was related to self-reported living within 100 meters of highway/major roads. Detection rates for the two biomarkers were over 95%, and females have higher 1-OHP and 1-OHPG levels (exp β: 1.56, 95% CI: 1.17 to 2.09; exp β: 1.49, 95% CI: 1.05 to 2.11, respectively) than males. Smoking in the 48-hour period before urine collection significantly predicted levels of biomarkers, and among non-smokers barbecued/grilled meat consumption was implicated in increases in 1-OHP. Conclusions: Those with lower household income and unemployment/student status experienced increased traffic exposure, while education, marital status and ethnicity were not associated with traffic exposure. While higher levels among females and an interaction with sex needs further study, PAH biomarkers are useful in capturing recent PAH exposure from smoking, and barbecued/grilled meat consumption. PAH biomarkers can be easily used in epidemiologic studies to assess general population exposures. / Thesis (Ph.D, Community Health & Epidemiology) -- Queen's University, 2013-07-30 10:41:50.321
29

Quantitative Comparison of Lidar Data and User-generated Three-dimensional Building Models From Google Building Maker

Liu, Yang 08 1900 (has links)
Volunteered geographic information (VGI) has received increased attention as a new paradigm for geographic information production, while light detection and ranging (LiDAR) data is widely applied to many fields. This study quantitatively compares LiDAR data and user-generated 3D building models created using Google Building Maker, and investigate the potential applications of the quantitative measures in support of rapid disaster damage assessment. User-generated 3D building models from Google Building Maker are compared with LiDAR-derived building models using 3D shape signatures. Eighteen 3D building models are created in Fremont, California using the Google Building Maker, and six shape functions (distance, angle, area, volume, slope, and aspect) are applied to the 18 LiDAR-derived building models and user-generated ones. A special case regarding the comparison between LiDAR data and building models with indented walls is also discussed. Based on the results, several conclusions are drawn, and limitations that require further study are also discussed.
30

Habitat, aménagement et gouvernance locale en Palestine : le cas de Naplouse / Housing, planning and local governance in Palestine : Nablus case study

Abushosha, Suhail 15 May 2013 (has links)
Ces dernières années, les villes Cisjordaniennes ont connu un développement urbain très dynamique mais cette urbanisation est aujourd’hui encadrée par des dispositifs législatifs et techniques hérités des périodes successives de colonisation qui ne sont plus adaptés à la ville contemporaine. Ce développement urbain anarchique s’est peu à peu inscrit dans les modes de pensée des acteurs locaux comme une nécessité justifiée par la situation géopolitique et ledéveloppement économique du pays. Le marché du logement s’est accru au point de devenir aujourd’hui une composante essentielle de la transformation des villes cisjordaniennes. Notre travail de recherche de six ans, dont les conclusions sont exposées dans cette thèse, a consisté à décrire puis analyser la réalité de ce marché qui soulève actuellement de nombreuses questions. En effet, le rythme soutenu de la construction de logements a laissé de côté des problématiques que nous avons souhaitées mettre en perspective ici. Ces processus interrogent tout d’abord la réalité et la cohérence de ce marché avec une offre qui doit correspondre à la demande tant sur le plan quantitatif que qualitatif. La situation du logement en Cisjordanie pose aussi la question de la structuration du tissu urbain qui transcende désormais les limites communales, les logiques foncières et les zones à risques. Enfin, se pose la question du cadre de vie pour les populations, le paysage urbain en devenir et la disparition d’une identité jusque là transmise en partie par l’habitat traditionnel. Ce travail de recherche appuyé par des entretiens et par la construction d’un véritable système d’informationsgéographiques a permis de vérifier l’adéquation entre d’un côté, le processus de production du logement et les volontés qui y sont associées, et de l’autre, la réalité du terrain et les enjeux réels du logement palestinien. L’absence de données géographiques et statistiques sur ce territoire nous a poussé à construire un outil complet d’analyse cartographique etdémographique permettant de décrire les phénomènes passés, d’analyser la situation présente et surtout de créer un modèle prospectif pour les horizons 2025 et 2050. A travers, le cas de la ville de Naplouse, il apparaît que les jeux d’acteurs constatés aujourd’hui, ne sont justifiés par aucune cohérence géographique ou démographique. A l’inverse, nous montrons ici que des logiques de marché intéressées sont à l’oeuvre, plaçant devant le fait accompli un cadrelégislatif et technique défaillant. Les conséquences, dès aujourd’hui visibles, constatées sur le terrain et cartographiées ici, interrogent sérieusement le caractère durable des villes cisjordaniennes. Ces résultats mettent en évidence un processus destructeur pour l’ensemble de l’armature urbaine de la Palestine et nécessite une réponse. La situation géopolitique et lagravité des risques identifiés nous poussent à proposer des préconisations pour la mise en place d’une véritable politique locale de l’habitat qui doit conditionner l'émergence d’une maîtrise urbaine. Portés par une gouvernance intercommunale à l’échelle de l’aire urbaine, nous décrivons un outil de planification et de programmation permettant à projet urbain depasser du marché du logement à la construction d’un véritable habitat / These last years, the West Bank cities knew a very dynamic urban development but this urbanization is framed(supervised) by legislative and technical devices(plans) inherited from the successive periods of colonization today which are not any more adapted to the contemporary city. This anarchy urban development joined little by little in the ways of thinking of the actors local as a necessity justified by the geopolitical situation and the economic development of the country. The market of the accommodation(housing) increased in the point of future today an essential component of the transformation(processing) of the West Bank cities. Our research work of six years, the conclusions of which are exposed(explained) in this thesis, consisted in describing then in analyzing the reality of this market which raises at present of numerous questions. Indeed, steady rhythm of the homebuilding left aside problems which we wished to put in perspective here. These processes question first of all the reality and the coherence of this market with an offer which has to correspond to the demand(request) both on the plan quantitative and qualitative. The situation of the accommodation(housing) in the West Bank also asks the question of the structuring of the urban fabric which transcends from now on the municipal limits, the land(basic) logics and the high-risk areas. Finally, asks itself the question of the living environment for the populations, the townscape to become and the disappearance of an identity to there there passed on(transmitted) partially by the traditional housing environment. This research work rested(supported) by conversations(maintenances) and by construction of a real system of geographical information allowed to verify the adequacy enter on one side, the process of production of the accommodation(housing) and the wills which are associated with it, and of the other one, the reality of the ground and the real stakes in the Palestinian accommodation(housing).The absence of geographical and statistical data on this territory urged to us to build a complete tool of cartographic and demographic analysis allowing to describe the past phenomena, to analyze the present situation and especially to create a forward-looking model for horizons 2025 and 2050. Through, the case of the city of Nablus, it seems that actors' games(sets) noticed today, are justified by no geographical or demographic coherence. On the contrary, we show here that interested logics of market are at work, presenting a fait accompli a failing legal and technical framework. The consequences, from today visible, noticed on the ground and mapped here, question seriously the long-lasting(sustainable) character of the West Bank cities. These results(profits) highlight a destructive process for the whole urban armature of Palestine and require an answer. The geopolitical situation and the gravity of the identified risks urge us to propose recommendations for the implementation of a real local politics(policy) of the housing environment which has to condition(package) the emergence of an urban control(master's degree). Carried(Worn) by an intermunicipal governance on the scale of the urban area, we describe a tool of planning and programming allowing urban project to depasser of the market of the accommodation(housing) in the construction of a real housing environment

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