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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.
101

Designing multimodal public transport networks using metaheuristics

Fletterman, Manuel 16 January 2009 (has links)
The public transport system in South Africa is in a precarious state, capturing no more than 50% of the passenger market. The three public transport modes that are currently utilized—train, bus, and minibus-taxi—are competing for market share instead of complementing one another. Furthermore, most public transport networks have not been properly redesigned over the past three decades. Improvements were initiated reactively in the past: transit stops and routes were added or removed from the network when demand fluctuated. This reactive process has diminished the confidence of commuters in the public transport networks, forcing commuters to use private transport. A proactive redesign method is needed—one that includes all the modes of public transport, and anticipates an increase in demand and rapid development in geographic areas, while ensuring good accessibility to the network. Current network design models do not include multiple modes of public transport, and are based on the geographical layout of developed cities and their particularities, which makes them unsuitable for the South African environment with its unique land use disparities. This dissertation proposes a multimodal network design model that is capable of designing real world and large scale networks for the South African metropolitan areas. The City of Tshwane Metropolitan Municipality (CTMM) transport network area was used to develop and test the model, which consists of four components. The Geographic Information System (GIS) component has a central role in storing, manipulating, and exchanging the geographic data within the model. For the GIS the appropriate input data is identified, and a design for the geo-database is proposed. The Population Generation Algorithm (PGA) component translates the demographic data into point data representing the transit demand in the study area. The Bus Stop Placement Algorithm (BSPA) component is a metaheuristic that searches for near-optimal solutions for the placement of bus stops in the study area. A novel solution approach proposed in this dissertation uses geographic data of commuters to evaluate the bus stop placement in the study area. The Multimodal Network Design Algorithm (MNDA) component also employs a metaheuristic, enabling the design of near-optimal multimodal networks. The addition of multiple modes to the Transit Network Design Problem (TNDP) is also a novel and significant contribution. The two metaheuristic components are first tested on a test network, and subjected to a comprehensive sensitivity analysis. After identifying suitable parameter values and algorithm settings, the components are applied to the entire CTMM. / Dissertation (MSc)--University of Pretoria, 2009. / Industrial and Systems Engineering / unrestricted
102

How to make the most of open data? A travel demand and supply model for regional bicycle paths / Hur får man ut det mesta av öppna data? En modell för utbud och efterfrågan för planering av regionala cykelvägar

Cazor, Laurent January 2021 (has links)
Detta examensarbete syftar till att svara på ett av Trafikverket fastställt problem: en gemensam regional cykelplanerings process skulle göra dem billigare och mer jämförbara. De erbjuder för närvarande planerarna en modell som utvecklades av Kågeson 2007. Denna modell har formen av en rapport som ger råd om när man ska bygga en cykelväg mellan städer eller platser i en region. Ändå används den bara i endast 6 av de 21 svenska länen. Trafikverket kräver ett nytt planeringsstödverktyg, mer interaktivt och komplett än Kågeson-modellen. Några nya önskade funktioner är separationen av efterfrågan per syfte, införandet av e-cyklar, olika resesyfte och en prioritering av investeringarna.  Examensarbetet är att designa och implementera det här verktyget, även kallat Planning Support System (PSS), som syftar till att jämföra utbud och efterfrågan på cykelväg till prioritering av infrastrukturförbättringar. En huvudbegränsning för modellen är att den måste vara billig datavis, men så komplett och exakt som möjligt. Det baseras på flera öppna dataleverantörer, till exempel OpenStreetMap, den svenska nationella vägdatabasen (NVDB) eller reseundersökningar från Sverige och Nederländerna. Resultatet är en modell, uppdelad efter turändamål och typ av cykel.  Del för efterfrågeuppskattning anpassar en klassisk fyrsteg transportmodell till cykelplanering och begränsad data. För olika resändamål genereras och distribueras resor tack vare en ursprungs begränsad gravitationsmodell. Valet av cykelläge är anpassat till det faktiska resebeteendet genom logistisk regression med en binär logit-modell. Resorna tilldelas sedan nätverket med tilldelnings metoden "allt-eller-ingenting" genom Dijkstras algoritm. För att utvärdera cykelförsörjningen använde vi ett mått som heter Level of Traffic Stress (LTS), som uppskattar den potentiella användningen av en nätverkslänk för olika delar av befolkningen som en funktion av vägnätvariablerna. Prioriteringsrankningen är då förhållandet mellan mått på efterfrågan och utbud.  Detta nya verktyg implementeras med opensource Geographic Information System (GIS) som heter QGIS och med Python 3 och testas i Södermanlands län / This Master Thesis main objective is to answer a problem set by the Swedish Transport Administration: a common regional bicycle planning process would them cheaper and more comparable. They currently offer the planners a model developed by Kågeson in 2007. This model takes the form of a report which advises on when to build a bicycle path between cities or places of a region. Still, it is only used in only 6 of the 21 Swedish counties. Trafikverket requires a new planning support tool, more interactive and complete than the Kågeson model. Some new desired features are the separation of demand per purpose, the inclusion of e-bikes, different trip purposes, and a prioritization of the investments.  The Degree Project work is to design and implement this tool, also called Planning Support System (PSS), which compares supply and demand for bicycle path to prioritizing infrastructure improvements. A main constraint for the model is that it needs to be cheap data-wise, but as complete and precise as possible. It bases on several open data providers, such as OpenStreetMap, the Swedish National Road Database (NVDB), or Travel Surveys from Sweden and the Netherlands. The result is a model, disaggregated by trip purpose and type of bicycle.  The demand estimation part adapts a classic four-step transportation model to bicycle planning and limited data. For different trip purposes, trips are generated and distributed thanks to an origin-constrained gravity model. Bicycle mode choice is fit to actual travel behaviour through logistic regression with a binary logit model. The trips are then assigned to the network using the "all-or-nothing" assignment method through the Dijkstra algorithm. To evaluate bicycle supply, we used a metric called Level of Traffic Stress (LTS), which estimates the potential use of a network link by different parts of the population as a function of the road network variables. The prioritization ranking is then the ratio between demand and supply metrics.  This new tool is implemented with the opensource Geographic Information System (GIS) called QGIS and with Python 3, and it is tested on Södermanland County.
103

[en] IMPROVING THE PROFITABILITY OF A PUBLIC TELEPHONE NETWORK USING A GEOGRAPHIC INFORMATION SYSTEM / [pt] MELHORANDO A RENTABILIDADE DE UMA REDE DE TELEFONIA PÚBLICA USANDO SISTEMA DE INFORMAÇÃO GEOGRÁFICA

DANIEL DE MELLO SCHAEFER 30 October 2006 (has links)
[pt] Este trabalho aborda o problema da baixa rentabilidade dos telefones públicos de uma concessionária de serviços de telecomunicações mantidos por exigência da regulamentação e propõe uma metodologia flexível e de baixo custo para aumentar a lucratividade desse negócio. O problema tem similaridade com o problema clássico de localização de máxima cobertura de Church e ReVelle e a revisão da bibliografia revelou modelos que poderiam ser adaptados para a solução. Entretanto detalhes práticos tornam a abordagem de programação matemática inadequada. Desenvolveu-se, por isso uma metodologia mais flexível capaz de incorporar o conhecimento tácito acumulado pelos técnicos responsáveis. Essa metodologia conjuga análise econômica e geográfica da planta instalada de telefones públicos numa área urbana. A análise econômica aponta os telefones públicos elegíveis para a retirada e a análise da localização geográfica identificará dentre os telefones elegíveis, quais podem ser retirados sem violar o plano geral de metas de universalização da Anatel, o PGMU, especificamente no que tange o telefone para uso público. Para a análise geográfica é utilizado um eficiente sistema de informação geográfica disponível no mercado. Os resultados indicam que com a retirada dos telefones de baixa rentabilidade a lucratividade global da planta pode aumentar consideravelmente. Adicionalmente acredita-se que pela sua flexibilidade, a metodologia seja aplicável a qualquer área urbana, sendo capaz de levar em conta as peculiaridades de cada caso. / [en] This research addresses the problem of a concessionary of telecommunications that in compliance to regulations has to maintain a low profitability system of public telephones and proposes a low cost and flexible methodology to increase the profitability of the business. The problem presents similarity with the classic maximum coverage location problem of Church and ReVelle and a bibliographic search revealed models that could be adapted for solution. Nonetheless, practical details render a mathematical programming approach inadequate. For this reason, a more flexible methodology was developed capable of incorporating the tacit knowledge accumulated by the technical staff. This methodology combines economic and geographic analyses of the public telephones installed in an urban area. The economic analysis indicates the public phones eligible for removal, and the geographic analysis points out the ones that can actually be removed without violating the rules set by the regulatory agency. The geographic analysis uses an efficient geographic information system readily available in the market. The results indicate that by removing the low profitability phones the total profitability can be considerably improved. Moreover, it is believed that due to its flexibility, the methodology is applicable to any urban area, being capable of taking into account the peculiarities of each case.
104

Digital Reconstruction of the Archaeological Landscape in the Concession Area of the Scandinavian Joint Expedition to Sudanese Nubia (1961–1964) / Digital rekonstruktion av det arkeologiska landskapet i koncessionsområdet tillhörande den Samnordiska Expeditionen till Sudanska Nubien (1960–1964)

Johansson, Carolin January 2014 (has links)
The Scandinavian Joint Expedition to Sudanese Nubia (SJE) was one of the substantial contributions of crucial salvage archaeology within the International Nubian Campaign which was pursued in conjunction with the building of the High Dam at Aswan in the early 1960’s. A large quantity of archaeological data was collected by the SJE in a continuous area of northernmost Sudan and published during the subsequent decades. The present study aimed at transferring the geographical aspects of that data into a digital format thus enabling spatial enquires on the archaeological information to be performed in a computerised manner within a geographical information system (GIS). The landscape of the concession area, which is now completely submerged by the water masses of Lake Nasser, was digitally reconstructed in order to approximate the physical environment which the human societies of ancient Nubia inhabited. Information on the nearly 500 indexed archaeological sites of the SJE was classified and imported into the GIS. The potential of the system thereby established, validated against modern remote sensing data and aerial photography, was then demonstrated by a number of spatial analyses at an inter-site level. The resuls of those analyses contribute to discussions on various topics already raised within the SJE publication or elsewhere and includes issues on Nile palaeochannel reconstructions, seasonal habitation patterns and dedicatory orientation of elite tombs. The system hereby developed is intended to be used in further studies of the relevant and information-rich research fields of ancient Nubia for applications similar to those demonstrated in the present project or for educational and research purposes hitherto unpredicted. / Den Samnordiska Expeditionen till Sudanska Nubien (SJE) var en av de omfattande insatser av avgörande räddningsarkeologi inom den Internationella Nubienkampanjen som bedrevs i samband med byggandet av Höga Dammen i Aswan i början av 1960-talet. En stor mängd arkeologisk data samlades in av SJE i ett kontinuerligt område i nordligaste Sudan och publicerades under de efterföljande årtiondena. Denna studie ämnade överföra de geografiska aspekterna av den datan till ett digitalt format och därmed möjliggöra att rumsliga förfrågningar på den arkeologiska information kan utföras på ett datoriserat tillvägagångssätt i ett geografiskt informationssystem (GIS). Landskapet i koncessions-området, vilket nu är helt översvämmat av Nassersjöns vattenmassor, återskapades digitalt med syfte att approximera den fysiska omgivningen vilken de mänskliga samhällena i det forna Nubien bebodde. Information om de nära 500 indexerade fyndplatserna tillhörande SJE klassificerades och importerades in i detta GIS. Potentialen av det system som därmed skapats, validerat mot modern fjärranalysdata och flygfotografi, demonstrerades genom ett antal rumsliga analyser på en mellan-fyndplats-nivå. Resultaten av dessa analyser bidrar till diskussioner om diverse ämnen som redan tagits upp inom SJE-publikationen eller annorstädes och inkluderar frågor kring Nilens äldre dragningar, säsongsmässiga bosättningsmönster och avsiktlig orientering av elitgravar. Systemet som härvid har utvecklats är ämnat att användas i vidare studier av de relevanta och informationsrika forskningsområden som rör det forna Nubien för tillämpningar liknande de som demonstrerats i detta projekt eller för undervisnings- och forsknings-syften som hittills ej förutsetts.
105

Investigation of Biotic and Abiotic Factors Affecting Double-Cropped Corn (Zea mays L.) Production in Virginia

Sforza, Peter M. 03 October 2005 (has links)
Double-cropping of corn (Zea mays L.) for grain following the harvest of a small grain crop has been under evaluation in Virginia as an alternative cropping strategy (Brann and Pitman, 1997). To assess the potential constraints on late planted corn imposed by insects and diseases, double-cropped corn was evaluated in field experiments in Montgomery County, Virginia from 1998 to 2000. Factors included two near-isoline hybrids (NK4640 and NK4640Bt), insecticides at planting (tefluthrin in all years, 1998-2000; and imidacloprid in 1999 and 2000), and fungicide treatments (azoxystrobin or propiconazole). Response variables included yield, moisture at harvest, grain test weight, damage by European corn borer (Ostrinia nubilalis), damage by corn earworm (Heliothis zea), disease progress curves for gray leaf spot Cercospora zeae-maydis), and number of plants exhibiting virus symptoms. The Bt hybrid performed significantly better than the non-Bt hybrid for yield and test weight in double-cropped corn in 1998 and 2000, but not in 1999. A spatially referenced site suitability analysis was performed for full season and double-cropped corn in Virginia using weighted abiotic factors and constraints. Thornthwaite potential evapotranspiration (PET) and PET minus precipitation were used to identify areas of the state having a lower average moisture deficit during the silking months for double-cropped corn compared to full-season corn. It is concluded that double-cropped corn production is a viable option in Virginia where abiotic factors are not constraining, particularly growing season length and moisture availability during the sensitive stages of development. / Master of Science
106

“Om det bara fanns ett GIS-program som var så enkelt” : En studie kring geografilärares relation till geografiska informationssystem i årskurs 7–9

Levan Clauson, Lucas January 2023 (has links)
Geografi som skolämne är nyanserat och innehållsrikt där specifika metoder och verktyg är väsentliga för inlärning. I och med ett utvecklande digitaliserat samhälle resulterar det till behovet av att lära ut datoriserande verktyg i geografi, däribland Geografiska informationssystem (GIS). Däremot förekommer det barriärer med hur geografilärare i årskurs 7-9 ska implementera kartverktyget, vilket leder till att syftet med undersökningen är att studera hur lärares relation till GIS ser ut. Metoderna som användes var genom semi-strukturerade intervjuer samt en enkätundersökning. Urvalet var baserat på ett kriteriebaserat urval där geografilärare i årskurs 7-9 var respondenterna. Geografilärarnas implementering av GIS var varierande, men samtidigt enhetlig där samtliga respondenter använde webbaserade GIS-tjänster, exempelvis Google Earth, och därmed ingen som genomför undervisning med GIS-mjukvaror. Därav upplevde respondenterna en explicit barriär med GIS-mjukvaror där de orsakande faktorerna var bland annat tid, bristfälliga kunskaper och att det var en ekonomisk fråga. Vid implementeringen av GIS indikerades även en slags omedveten barriär som innefattar att lärare har en ensidig definition och bild av GIS, vilket oftast hänvisas till GIS-mjukvaror. Kontentan av undersökningen är att geografilärares implementering, upplevelse och tolkning baseras på tidigare erfarenheter och utifrån Skolverkets styrdokument, vilket praktiseras genom enkla former av GIS, däribland webbaserade GIS-applikationer.
107

Cobia cage culture distribution mapping and carrying capacity assessment in Phu Quoc, Kien Giang province: Research article

Nguyen, Thi Hong Diep, Wenresti, Glino Gallardo, Nitin, Kumar Tripathi, Truong, Hoang Minh 14 November 2013 (has links)
Cobia fish cage is the most popular marine culture species raised in Phu Quoc Island, Vietnam. For its sustainable development, there is a need to determine the carrying capacity to avoid nega-tive marine environmental impact in the future. This study was carried out to collect water samples each two months at the lowest and highest tides at four points around the farming area in Rach Vem, Phu Quoc Island, Kien Giang Province from February to October 2011. Water quality in cobia cage culture was surveyed to assess the environmental status of coastal aquaculture areas including seven parameters such as DO, COD, BOD, TSS, TN, TP and Chlorophyll-a. These parameters are suitable to rear cobia fish cage in this area. Nitrogen and phosphorus are considered as the principal nutrients produced by the cobia fish farm and affecting water environment. This study found that the carrying capacity for fish cage farming in the area is 290.96 to 727.81 tons (based on total nitrogen) and 428.64 to 1,383.88 tons (based on total phosphorus) from February to Au-gust 2011. The maximum number of cobia cages should be, based on total nitrogen, from 64 to 266 and, based on total phosphorus, from 94 to 253. Moreover, this study examined the possibility of remote sensing and geographic information system (GIS) technique based on Object-based Image Analysis (OBIA) method by THEOS imagery for mapping of cage culture facilities and detect the location for cobia cage culture in study area. / Cá bớp nuôi lồng bè là một trong những loài cá nuôi phổ biến khu vực ven biển Phú Quốc, Việt nam. Nhằm phát triển bền vững vùng ven biển, đề tài thực hiện đã xác định và đánh giá hiện trạng môi trường nước và sức tải môi trường của nghề nuôi cá bớp lồng bè ở đảo Phú Quốc. Nghiên cứu này được thực hiện thông qua việc thu mẫu môi trường nước mỗi 2 tháng theo mức nước triều cao nhất và thấp nhất tại 4 điểm quanh khu vực nuôi tại ấp Rạch Vẹm, huyện Phú Quốc, tỉnh Kiên Giang từ tháng 02-10/2011. Chất lượng nước khu vực nuôi thủy sản cũng được khảo sát với 7 chỉ tiêu gồm DO, COD, BOD, TSS, TN, TP, Chlorophyll-a. Các thông số chất lượng môi trường này phù hợp nuôi cá bớp tại khu vực nghiên cứu dựa trên tiêu chuẩn chất lượng môi trường. Trong nghiên cứu này, đạm và lân là 2 thông số được sử dụng để tính toán sức tải môi trường. Sức tải môi trường được tính toán cho khu vực nuôi cá bớp dao động khoảng từ 290.96 tấn đến 727.81 tấn (tính trên hàm lượng đạm tổng số) và từ 428,64 tấn đến 1.383,88 tấn (tính trên hàm lượng lân tổng số) trong thời gian từ tháng 2 đến tháng 10 năm 2011. Số lượng tối đa lồng bè nuôi cá bớp khoảng từ 64 đến 266 (đạm tổng số) và từ 94 đến 253 (lân tổng số) dựa vào phân tích hồi quy tương quan. Bên cạnh đó, công nghệ viễn thám và hệ thống thông tin địa lý (GIS) đã được ứng dụng bằng cách sử dụng ảnh THEOS để xác định vị trí và phân bố không gian khu vực nuôi cá lồng bè dựa trên phương pháp phân tích đối tượng theo hướng (OBIA).
108

Identifiering av platser att anlägga fickparker på med hjälp av multikriterieanalys

Ivarsson, Felicia, Sundin-Anders, Samuel January 2016 (has links)
Målet med studien är att med hjälp av multikriterieanalyser hitta platser i Gävle tätort att anlägga fickparker på. Till en början gjordes en litteraturöversikt som bland annat bidrog med uppfattningen om vad som är viktigt för fickparker och vilka kriterier som är användbara för att hitta platser att anlägga fickparker på. Utifrån denna uppfattning samt intervjuer valdes kriterierna. Kriterierna skapades i form av restriktioner och faktorer i programmet ESRI ArcGIS 10.2. Intervjuer genomfördes med tre sakkunniga personer. Respondenterna rangordnade och diskuterade kriterierna utifrån vad de ansåg var minst respektive mest viktigt vid anläggandet av fickparker. Rangordningarna blev underlag till viktning av kriterierna (enligt rank-sum-weights). En känslighetsanalys genomfördes också för att testa kriterierna mot fler uppsättningar av vikter. Resultatet av analyserna redovisas på tre kartor baserat på en egen rangordning samt respondenternas. Kartorna visar de bästa platserna att anlägga fickparker på enligt respektive rangordning. Skillnader finns mellan kartorna, men oavsett hur kriterierna rangordnades blev ungefär samma platser valda som de bästa att anlägga fickparker på. De tre bästa platserna som är gemensamma för alla tre rangordningar är alla lokaliserade på Norr (norr om Gavleån). Resultatet av analysen visade att platser som inte på förhand är uppenbara kan bli valda som lämpliga för fickparker. / The purpose of this study is to locate places in Gävle to create pocket parks in, using multi criteria analyzes. Initially a literature review was made that, among other things, contributed with an understanding of what is important to pocket parks and which criteria that is useful in order to locate places to create pocket parks in. The criteria were chosen based on that understanding and interviews. The criteria were produced in the form of constraints and factors in ESRI ArcGIS 10.2. Interviews were conducted with three experts in the field. The interviewees ranked and discussed the criteria based on what they considered to be least and most important in the creation of pocket parks. Weighting of the criteria was based on the gathered rankings (using rank-sum-weights). A sensitivity analysis was conducted to test the criteria against more sets of weights. The results from the analyzes are presented on three maps based on a self-made rank as well as the ones that the interviewees made. The maps show the best locations to create pocket parks in accordance to each rank. There are differences between the maps, but approximately the same locations are chosen as the best ones no matter how the criteria were ranked. The three best locations that the ranks have in common are all located in Norr (north of Gavleån). The results from the analysis demonstrate that locations that pre-analysis aren’t obvious can be chosen as suitable for the creation of pocket parks.
109

A Conceptual Framework for an Enterprise-Wide Geospatially Enabled Information Management System for Transportation Right-Of-Way Business Processes

Sambana, Kavya 09 June 2010 (has links)
Right-of-way business processes have been identified as one of the areas where information bottlenecks occur in transportation agencies, not only because of the amount of information involved, but also because of the interdependent nature of these activities. Transportation projects are associated with parcels whose status change during and after the project based on information from right-of-way activities. Geospatially enabled decision making tools enhance data interpretation as well as data retrieval of this information. By using enterprise-level applications, information sharing between the transportation agency, other jurisdictions, and the public becomes more efficient. Being able to quickly visualize the status of parcels in a geospatial environment further enhances the management of resources which, in turn, improves timely project delivery. This thesis presents a conceptual framework for an information management system and its geospatial enablement through a logical model for Geospatial Decision Making Activities (GDMA) in transportation right-of-way offices. The logical model for GDMA, presented in Unified Modeling Language, includes state machine diagram and data flow diagram models for tracking the parcel and capturing the geospatial enablement of right-of-way activities. / Master of Science
110

Utilisation de systèmes d'information géographique pour l'évaluation des risques liés à la dégradation du pergélisol. Étude de cas : Tasiujaq, Nunavik, Québec

Grandmont, 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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