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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.
421

Automatic Generation of Levels of Detail : A Study on the Swedish National Road Database / Automatisk generering av detaljnivåer

Börjesson, Alexandra January 2019 (has links)
When creating a map, the amount of data and which geographical information chosen to bepresented are decided based on the purpose of the map. Trafikverket is responsible for theNational Road Database that is a reference road network with a large amount of dataconnected to it. The database is built at a carriageway level where several links can be usedto represent a single road. In this thesis the database has been studied as well as thepossibilities to create an automatic workflow that creates a generalisation to road level. Someapplications and analyses that use this database are requesting input data of a higher level ofdetail. It is also found important from a cartographic point of view. Possibilities to create alinear referencing for the data between the different levels was studied as well, to make theupdates between the levels easier and not having the need to maintain two differentdatabases. It would make it possible to inherit attributes and the generic features connectedto the network.The first fully automated workflow for a generalisation of an entire map was developed in theNetherlands in 2014. Several other agencies in Sweden and Norway are currently working ongeneralisations as well and using different approaches. Statens Vegvesen, which is theNational Road Agency in Norway, has already implemented the different levels of detail intheir road database. Lantmäteriet currently has a project where their goal is to create a fullyautomated map to easily change to a larger scale.After studying the programs used in other generalisations and which programs Trafikverketnormally use, FME and ArcGIS were chosen to be used in this thesis. A small study area waschosen, and the proper data was collected from the National Road Database. The study wasconducted by a set of experiments and trying different parameter values in order to obtain asatisfactory result.Three different areas where studied, where the goal was to find a sequence of functions thatsuccessfully generalised all the areas. The areas were parallel roads, complex intersectionsand roundabouts. The result consists of a suggested workflow, but alterations hade to bemade manually since it was not possible to find a fully automated generalisation for the areachosen. Therefore, a set of functions and tools that could be developed were collected as wellin the end to make a more automated workflow possible.The result found in this thesis show that if the cartographic generalisations are more studiedand examined it should be possible to get a more automated workflow to create ageneralisation between the different level of detail. However, it might be difficult to get theworkflow fully automated due to the complexity of the intersections. / När en karta skapas baseras mängden data och vilken geografisk information som skaförmedlas beroende på syftet med kartan. Trafikverket ansvarar för den NationellaVägdatabasen som är ett referensvägnät med en stor mäng data kopplad till vägnätet.Referensvägnätet är byggt på en körbanenivå. I det här arbetet har databasen studerats ochvilka möjligheter som finns för att skapa en automatisk generalisering till vägnivå. Det finnsett behov att representera data på en annan detaljnivå för vissa applikationer och analysersom använder sig av vägdatabasen. Det är även viktigt utifrån ett kartografiskt synsätt.Möjligheterna att skapa en linjär referering mellan de olika detaljnivåerna har undersökts, föratt förenkla uppdateringar mellan nivåerna samt att inte behöva ajourhålla två olikadatabaser. Det skulle även göra det möjligt att attribut och företeelser kan ärvas mellan deolika nivåerna.Det fösta helt automatiserade arbetsflödet för en generalisering av en karta utformades 2014i Nederländerna. Flera andra myndigheter i Sverige och Norge arbetar just nu med den härtypen av generaliseringar och har använt sig av olika tillvägagångssätt. Statens Vegvesen,vilket är den statliga myndighet som ansvarar för vägar i Norge, har redan implementerat olikadetaljnivåer i deras vägdatabas. Lantmäteriet har ett projekt med målet att skapa en fulltautomatisk generalisering för olika skalor.Efter att ha studerat de olika program som vanligtvis används vid generaliseringar samt vilkaprogram som Trafikverket använder sig av så valdes FME och ArcGIS i det här arbetet. Ettmindre studieområde valdes ut och relevant data hämtades från den NationellaVägdatabasen. Studien bestod av olika experiment och tester av olika parametervärden föratt få ett acceptabelt resultat.Tre olika områden studerades, där målet var att hitta en följd operationer som skapade enlämplig generalisering för alla områden. De tre olika områdena var parallella vägar,trafikplatser och cirkulationsplatser. Resultatet består av förslag på ett arbetsflöde, men delarhar behövt göras manuellt då det inte var möjligt att hitta en helt automatiseradgeneralisering för det valda området. Förslag på olika funktioner och verktyg som kanutvecklas har sammanställts, för att kunna utvecklade ett mer automatiserat arbetssätt.Resultatet av det här arbetet visar att om kartografiska generaliseringar studeras och testasmer skulle det kunna vara möjligt att skapa ett mer automatiserat arbetssätt med syfte attmöjliggöra generaliseringar mellan olika detaljnivåer. Det kan däremot vara svårt att få dettahelt automatiserat på grund av de olika komplexa trafikplatserna.
422

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.
423

[pt] ROTEIRIZAÇÃO DE VEÍCULOS NO PROCESSO DE ATENDIMENTO ÀS DEMANDAS DE MANUTENÇÃO DE UMA UNIVERSIDADE PÚBLICA / [en] VEHICLE ROUTING IN THE PROCESS OF MEETING THE MAINTENANCE DEMANDS OF A PUBLIC UNIVERSITY

HIGOR COIMBRA LUCINDO 30 April 2021 (has links)
[pt] Na atualidade, as organizações públicas e privadas buscam otimizar seus processos de modo que, estes garantam a qualidade dos serviços e o retorno sobre o capital investido nas diversas operações que estão envolvidas. Com isso, as organizações que não se preocupam em desenhar seus processos com eficácia e eficiência, estarão sujeitas a falhas, onerando assim os custos de operação. O estudo em questão propõe uma política de atendimento às demandas de manutenção e a utilização de uma ferramenta de roteirização diária no desempenho das operações do setor de manutenção de uma universidade pública do estado de Minas Gerais. O Problema de Roteirização de Veículos (PRV), do inglês Vehicle Routing Problem (VRP), como é conhecido na literatura, é definido como o atendimento a pontos de demanda geograficamente dispersos, por intermédio de uma frota de veículos disponíveis que, em geral, partem e retornam a um depósito central. O PRV tem como objetivo encontrar rotas viáveis com um menor custo que respeite as restrições operacionais, como duração da jornada de trabalho, capacidade dos veículos, duração das rotas, entre diversas outras. No trabalho será proposta uma metodologia que sugere uma nova política de distribuição de profissionais e materiais necessários para realização dos atendimentos às demandas de manutenção das unidades internas e externas da universidade e faz uso de um software de solução do PRV para verificar o desempenho das políticas propostas. Os resultados do estudo para as estratégias propostas apresentaram reduções significativas, variando de 17,86 porcento a 66,27 porcento do custo mensal, além de oportunidades de ganhos operacionais frente ao cenário atual. Espera-se que o software de PRV seja utilizado na programação diária dos roteiros dos veículos do setor. / [en] Currently, public and private organizations seek to optimize their process-es in order to guarantee the quality of services and the return on capital invested in the various operations that are involved. As a result, organizations that are not concerned with designing their processes effectively and efficiently, will be sub-ject to failures, thus increasing operating costs. The study in question proposes a policy to meet maintenance demands and the use of a daily routing tool in the performance of operations in the maintenance sector of a public university in the state of Minas Gerais. The Problema de Roteamento de Veículos (PRV), from the English Vehicle Routing Problem (VRP), as it is known in the literature, is defined as the service to meet geographically dispersed demand points, through a fleet of available vehicles that, in general, depart and return to a central depot. The VRP aims to find viable routes at a lower cost that respects operational re-strictions, such as working hours, vehicle capacity, duration of routes, among others. In the work, a methodology will be proposed that suggests a new policy for the distribution of professionals and materials needed to fulfill the demands of maintenance of the university s internal and external units and makes use of a VRP solution software to verify the performance of the proposed policies. The results of the study for the proposed strategies showed significant reductions, varying from 17.86 percent to 66.27 percent of the monthly cost, in addition to opportunities for operational gains compared to the current scenario. It is expected that the VRP software will be used in the daily programming of the routes for vehicles in the sector.
424

[pt] MAPEAMENTO DE ÁREAS DE RISCO DE FLUXO DE DETRITOS COM BASE EM MODELO GIS / [en] MAPPING OF DEBRIS FLOW RISK AREAS BASED ON A GIS MODEL

PAULA MORAIS CANEDO DE MAGALHAES 31 August 2021 (has links)
[pt] A identificação de áreas com predisposição à ocorrência de desastres naturais surge como informação importante, principalmente no contexto urbano. Sendo assim, o objetivo desse estudo foi propor uma metodologia para o mapeamento de áreas de risco de fluxo de detritos, considerado como um dos acidentes naturais que mais provocam mortes e perdas materiais. Para tanto, esse estudo fez a modelagem de estabilidade das encostas diretamente num software GIS, em que foram utilizados o Modelo do Talude Infinito, para o cálculo da estabilidade, e do Método CN, como modelo de infiltração. Na análise de risco, considerou-se que Risco é definido pelo produto da probabilidade de ocorrência de um fluxo de detritos (Perigo), onde é avaliada a influência das características do meio físico e do seu processo deflagrador; com a severidade das suas consequências, medidas em termos de população afetada (Exposição) e suas fragilidades (Vulnerabilidade). Os resultados obtidos foram satisfatórios, indicando que a metodologia foi adequada para atingir os objetivos propostos, qualificando-a como viável e promissora para estudos futuros. Dentre as suas vantagens tem-se: ser facilmente replicada para outras áreas de estudo, possuir uma sequência simples de cálculos possuir dados de entrada de fácil obtenção e apresentar baixo custo computacional. / [en] The identification of areas prone to the occurrence of natural disasters is an important information, especially in urban areas. Therefore, this study aimed to propose a methodology for debris flow risk assessment, considered as one of the natural disasters that most cause deaths and material losses. To this end, this study made the slope stability modeling directly in a GIS software, in which the Infinite Slope Model was used for the slope stability calculation, and the CN Method, as the infiltration model. For the risk assessment, Risk is defined by the product of the probability of the occurrence of a debris flow event (Hazard), where the influence of the environment s physical characteristics and its triggering process are evaluated; with the severity of its consequences, measured in terms of the affected population (Exposure) and its weaknesses (Vulnerability). The results obtained were satisfactory, indicating that the methodology presented was adequate to achieve the proposed objectives, qualifying it as viable and promising for future studies. Among its advantages: being easily replicated to other areas of study; have a simple sequence of calculations; have easily obtainable input data; and present low computational cost.
425

[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.
426

Advancing the use of geographic information systems, numerical and physical models for the planning of managed aquifer recharge schemes

Sallwey, Jana 12 November 2020 (has links)
Global change is a major threat to local groundwater resources. Climate change and population growth are factors that directly or indirectly augment the increasing uptake of groundwater resources. To outbalance the pressure on aquifers, managed aquifer recharge (MAR) schemes are increasingly being implemented. They enable the subsurface storage of surplus water for times of high demand. The complexity of MAR schemes makes their planning and implementation multifaceted and requires a comprehensive assessment of the local hydrogeological and hydrogeochemical conditions. Despite the fact that MAR is a widely used technique, its implementation is not well regulated and comprehensive planning and design guidelines are rare. The use of supporting tools, such as numerical and physical models or geographic information systems (GIS), is rising for MAR planning but their scope and requirements for application are rarely reflected in the available MAR guidelines. To depict the application potential and the advantages and disadvantages of the tools for surface infiltration MAR planning, this thesis comprises reviews on the past use of the tools as well as suggestions to improve their applicability for MAR planning. GIS is not mentioned by most MAR guidelines as a planning tool even though it is increasingly being used for MAR mapping. Through a review of GIS-based MAR suitability studies, this thesis shows that the MAR mapping process could be standardized by using the often-applied approach of constraint mapping, suitability mapping by using pairwise comparison for weight assignment and weighted linear combination as a decision rule, and a subsequent sensitivity analysis. Standardizing the methodology would increase the reliability and comparability of MAR maps due to the common methodological approach. Thus, the proposed standard methodology was incorporated into a web GIS that simplifies MAR mapping through a pre-defined workflow. Numerical models are widely used for the assessment of MAR schemes and are included into some MAR planning guidelines. However, only a few studies were found that utilized vadose zone models for the planning and design of MAR schemes. In this thesis, a review and a subsequent case study highlight that numerical modelling has many assets, such as monitoring network design or infiltration scenario planning, that make its utilization during the MAR planning phase worthwhile. Consequently, this study advocates the use of vadose zone models for MAR planning by showing their potential areas of application as well as their uncertainties that need to be regarded carefully during modelling. Physical models used for MAR planning are typically field or pilot sites, as some MAR legislation requests pilot sites as part of the preliminary assessment. Laboratory experiments are used less often and are mostly restricted to the analysis of very specific issues, such as clogging. This thesis takes on the issue of scaling laboratory results to the field scale by comparing results from three physical models of different scales and dimensionality. The results indicate that preferential flow paths, air entrapment and boundary influence limit the quantitative validity of laboratory experiments. The use of 3D tanks instead of 1D soil columns and the application of statistical indicators are means to increase the representativeness of laboratory measurements. Nevertheless, physical models have the potential to improve MAR planning in terms of detailed process assessment, scenario and sensitivity analyses. All tools discussed in this thesis have their merits for MAR scheme planning and should be advocated better in MAR guidelines by depicting their application potential, advantages and disadvantages. The information accumulated in this thesis is a step towards an advanced use of supporting tools for the planning and design of MAR schemes.:1 Introduction 1.1 Motivation 1.2 Objectives 1.3 Structure of the thesis 2 Status quo of the planning process of MAR schemes 2.1 Guidance documents on general MAR planning 2.2 Application of GIS, numerical and physical models for MAR planning 2.3 Planning of surface infiltration schemes 3 Using GIS for the planning of MAR schemes 3.1 Implications from GIS-MCDA studies for MAR mapping 3.2 Development of web tools for MAR suitability mapping 4 Using numerical models for the planning of MAR schemes 4.1 Review on the use of numerical models for the design and optimization of MAR schemes 4.2 Planning a small-scale MAR scheme through vadose zone modelling 5 Using physical models for the planning of MAR schemes 5.1 Design of the experimental study 5.2 Comparison of three different physical models for MAR planning 6 Discussion and research perspectives 7 Bibliography 8 Appendix / Der globale Wandel stellt eine große Bedrohung für die lokalen Grundwasserressourcen dar. Klimawandel und Bevölkerungswachstum sind Faktoren, die, direkt oder indirekt, die zunehmende Nutzung von Grundwasserressourcen verstärken. Um diesen Druck auf die Grundwasserleiter auszugleichen, werden verstärkt Maßnahmen zur gezielten Grundwasserneubildung (managed aquifer recharge = MAR) durchgeführt. Dies ermöglicht die unterirdische Speicherung von überschüssigem Wasser für Zeiten hohen Bedarfs. Die Komplexität von MAR-Anlagen macht ihre Planung und Umsetzung kompliziert und erfordert eine umfassende Bewertung der lokalen hydrogeologischen und hydrogeochemischen Bedingungen. Trotz der weltweiten Implementierung von MAR ist dessen Planung wenig reguliert. Umfassende Planungs- und Gestaltungsrichtlinien sind rar. Der Einsatz unterstützender Werkzeuge, wie numerischer und physikalischer Modelle oder Geoinformationssysteme (GIS), nimmt bei der MAR-Planung zu, aber ihre Einsatzmöglichkeiten und ihre Anforderungen an die Anwendung spiegeln sich selten in den verfügbaren MAR-Richtlinien wider. Um das Anwendungspotential und die Vor- und Nachteile der Werkzeuge für die MAR-Planung darzustellen, wurden für diese Arbeit Recherchen über den bisherigen Einsatz der Werkzeuge durchgeführt. Zusätzlich wurden Vorschläge zur Erhöhung ihrer Anwendbarkeit für die MAR Planung gemacht. Der Schwerpunkt lag dabei auf Oberflächeninfiltrationsverfahren. GIS wird in keiner MAR-Richtlinie als Planungsinstrument erwähnt, obwohl es zunehmend für die MAR-Kartierung eingesetzt wird. Eine Recherche über GIS-basierte MAR-Eignungsstudien zeigte, dass der MAR-Kartierungsprozess standardisiert werden kann mittels des oft genutzten Ansatzes: initiales Ausschneiden von Gebieten, welche Restriktionen unterliegen, dem folgend die Eignungskartierung mittels Paarvergleich für die Wichtung der GIS-Karten und der gewichteten Linearkombination als Entscheidungsregel, sowie eine abschließende Sensitivitätsanalyse. Die Standardisierung der Methodik könnte die Zuverlässigkeit und Vergleichbarkeit von MAR-Karten aufgrund des gemeinsamen methodischen Ansatzes erhöhen. Daher wurde die standardisierte Methodik in ein Web-GIS integriert, das über einen definierten Workflow die MAR-Kartierung vereinfacht. Numerische Modelle werden häufig für die Beurteilung von MAR-Systemen verwendet und sind in einigen MAR-Planungsrichtlinien ausgewiesen. Es wurden jedoch nur wenige Studien gefunden, die die Modelle der ungesättigten Zone für die Planung und Gestaltung von MAR Standorten verwendeten. Die in dieser Arbeit durchgeführte Literaturrecherche und eine darauf aufbauende Fallstudie zeigen, dass die numerische Modellierung viele Vorteile bietet, wie z. B. beim Design eines Monitoring-Netzwerkes oder bei der Planung von Infiltrationsszenarien. Physikalische Modelle, die für die MAR-Planung verwendet werden, sind meist Feld- oder Pilotversuche, da einige MAR-Gesetzgebungen Pilotstandorte im Rahmen der Vorabbewertung verlangen. Laborexperimente werden seltener eingesetzt und beschränken sich meist auf die Analyse sehr spezifischer Fragestellungen, wie z.B. der Kolmatierung. Diese Arbeit beschäftigt sich mit der Skalierbarkeit von Laborergebnissen auf die Feldskale, indem sie Ergebnisse aus drei physikalischen Modellen verschiedener Maßstäbe und Dimensionen vergleicht. Die Ergebnisse deuten darauf hin, dass Makroporen, Lufteinschlüsse und der Einfluss der Randbedingungen die quantitative Aussagekraft von Laborversuchen einschränken. Der Einsatz von 3D-Tanks anstelle von 1D-Bodensäulen oder von statistischen Indikatoren ist ein Mittel zur Erhöhung der Repräsentativität von Labormessungen. Nichtsdestotrotz hat die Anwendung physikalischerModelle das Potenzial, die MAR-Planung in Bezug auf detaillierte Prozessbewertung, Szenarien und Sensitivitätsanalysen zu unterstützen. Alle beschriebenen Instrumente haben ihre Vorzüge bei der Bewertung von MAR-Anlagen und sollten in MAR-Richtlinien detaillierter berücksichtigt werden, indem ihr Anwendungspotenzial, ihre Vor- und ihre Nachteile dargestellt werden. Die für diese Arbeit zusammengestellten Informationen sind ein Schritt zur Förderung der beschriebenen Planungsinstrumente für die Planung und Gestaltung von MAR-Anlagen.:1 Introduction 1.1 Motivation 1.2 Objectives 1.3 Structure of the thesis 2 Status quo of the planning process of MAR schemes 2.1 Guidance documents on general MAR planning 2.2 Application of GIS, numerical and physical models for MAR planning 2.3 Planning of surface infiltration schemes 3 Using GIS for the planning of MAR schemes 3.1 Implications from GIS-MCDA studies for MAR mapping 3.2 Development of web tools for MAR suitability mapping 4 Using numerical models for the planning of MAR schemes 4.1 Review on the use of numerical models for the design and optimization of MAR schemes 4.2 Planning a small-scale MAR scheme through vadose zone modelling 5 Using physical models for the planning of MAR schemes 5.1 Design of the experimental study 5.2 Comparison of three different physical models for MAR planning 6 Discussion and research perspectives 7 Bibliography 8 Appendix
427

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
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[pt] FERRAMENTAS ESPACIAIS EM SIG PARA A ANÁLISE DE ACIDENTES DE TRÂNSITO: ESTUDO DE CASO COM VEÍCULOS PESADOS NAS RODOVIAS FEDERAIS DO ESTADO DO RIO DE JANEIRO / [en] SPATIAL TOOLS IN GIS FOR ANALYSIS OF TRAFFIC ACCIDENTS: CASE STUDY WITH HEAVY VEHICLES ON FEDERAL HIGHWAYS IN THE STATE OF RIO DE JANEIRO

SAMIR BORGES BRESSANE 04 October 2021 (has links)
[pt] Aliada à incorporação do automóvel no cotidiano da sociedade, emerge um relevante problema social: os acidentes de trânsito. O impacto destes acontecimentos é tal que esses eles custam à maioria dos países cerca de 3 por cento do seu Produto Interno Bruto (PIB). No Brasil, um país majoritariamente rodoviário, a malha concentra cerca de 60 por cento do volume de cargas transportadas e 90 por cento do total de passageiros. Quando se fala de veículos pesados, a situação é ainda mais grave, expostos a jornadas de trabalho, exaustivas, caminhoneiros trabalham em um ambiente em que o risco, a falta de segurança, a infraestrutura viária e o tempo de isolamento podem gerar acidentes de maior gravidade nas rodovias federais. No Estado do Rio de Janeiro, a frota de veículos está em crescente expansão e necessita de formas de controle para os riscos dos acidentes. Com a evolução das geotecnologias, estudos georreferenciados, quando inseridos em um Sistema de Informação Geográfica (SIG), têm permitido uso de técnicas estatísticas espaciais e de otimização para tomada de decisões. Este trabalho teve como objetivo estudar ferramentas em SIG nas análises de acidentes de trânsito envolvendo veículos pesados nas rodovias federais no Estado do Rio de Janeiro. O trabalho demonstrou as capacidades de SIG, à luz da literatura atual e metodologias oficiais, na identificação dos pontos críticos de acidentes no Estado do Rio de Janeiro e, por utilizar banco de dados, as metodologias podem ser replicadas, aperfeiçoadas ou expandidas em outras regiões. / [en] Allied to the incorporation of the automobile in the daily life of society, a relevant social problem emerges: traffic accidents. While in developed countries great effort is done to control them, in developing countries, with an unstable growth, they appear as a growing problem (MARIN and QUEIROZ, 2000). The impact of these events is such that these accidents cost most countries around 3 percent of their Gross Domestic Product (GDP) (GONIEWICZ et al., 2015; WHO, 2018). Traffic injury is now the leading cause of death for children and young adults aged 5 to 29 years. And it presents itself as the eighth leading cause of death in all age groups, more than AIDS, tuberculosis and diarrhea (ITF, 2017; WHO, 2018). In Brazil, a mainly road country, the network concentrates about 60 percent of the volume of cargo transported (and 90 percent of the total passengers). Reports, referring to 2016 data, show that Brazil appears in third place among the record-breaking countries in traffic deaths, behind only India and China (WHO, 2018). When it comes to heavy vehicles, the situation is even worst. According to a report by the Ministry of Transport, Ports and Aviation, trucks represent about 6 percent of the vehicle fleet in Brazil, however they are involved in 16.7 percent of all accidents, and with greater severity, in federal roads (BRASIL, 2017). Exposed to working hours, often exhausting, truck drivers work in risky situations, in which the lack of security and time away from their family members are the main negative points of the profession (CNT, 2019b). Rio de Janeiro State has an expanding fleet, estimated at about 6,725,822 vehicles (IBGE, 2020). Information from the Transit Dossier, a survey carried out by the Public Security Institute (ISP) and DETRAN-RJ, show that in 2018, 1,957 people died and 27,520 were injured in traffic accidents in Rio de Janeiro State, an average of six victims fatal every day (BOECHAT, 2019). Traffic accident locations are crucially important information for understanding the causes and implementation of traffic safety measures. With the evolution of geotechnologies, this field starts to gain a lot of strength. georeferenced studies allow the use of statistical techniques for analysis and optimization for decision making when inserted in a Geographic Information System (GIS) (SILVA et al., 2009; HASHIMOTO, 2016). This work aims to study GIS tools in the analysis of traffic accidents, using a case study of heavy vehicles on federal roads in Rio de Janeiro State. The methodology adopted for the elaboration of this research was of exploratory research, with a bibliographic review of the concepts and historical roads in Brazil, as well as the methodologies in existing Geographic Information Systems. With a subsequent application case study and methodological comparison.
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“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.
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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).

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