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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.
321

Vegetation, climate and fire dynamics of Upper Montane Forest and Campos de Altitude during the Holocene in southeastern Brazil

Guarinello de Oliveira Portes, Maria Carolina 23 September 2019 (has links)
O bioma Mata Atlântica é mundialmente reconhecido como uma das regiões de maior diversidade biológica do planeta, abrigando elevada riqueza de espécies e um elevado número de espécies endêmicas, se estendendo por cerca de 1.300.000 km2 ao longo da costa brasileira, entre as latitudes 3º e 33º S e longitudes 35º e 57º L. Como resultado do incremento das atividades humanas de uso da terra e, consequentemente, de ampla modificação da paisagem ao longo dos séculos, cerca de apenas 10-15% do bioma Mata Atlântica ainda se encontra em estado natural ou próximo ao natural, sendo considerados áreas prioritárias para conservação. Devido à grande variedade climática e geomorfológica, o bioma Mata Atlântica é um complexo mosaico de diferentes ecossistemas. Dentre estes, a floresta com Araucária (Floresta Ombrófila Mista), a floresta nebular (Floresta Ombrófila Densa Altomontana) e os campos de altitude ocupam as médias e altas altitudes da Serra do Mar, que se estende por cerca de 1000 km paralela à costa, do sul ao sudeste brasileiro. A distribuição da floresta com Araucária está relacionada ao clima úmido e relativamente frio, entre 400 e 1400 m s.n.m. no sul do Brasil e em fragmentos menores entre as altitudes de 1400 a 1800 m s.n.m. no Sudeste. Atualmente, está reduzida a não mais do que 7% da sua distribuição original. A floresta nebular se estende nas encostas do alto da Serra do mar, normalmente acima de 1100 m s.n.m. no Sul e acima de 1500 m s.n.m. no sudeste do Brasil, nos pequenos vales e sítios protegidos. Os campos de altitude são uma vegetação tipicamente herbácea, restrita aos cumes e picos da serra e aos platôs mais elevados. Estudos paleoecológicos demonstraram que, apesar deste mosaico de ecossistemas ter persistido durante o Holoceno, a perpetuação dos campos de altitude é muito frágil. Como a vegetação campestre se expande em condições climáticas mais frias e secas e parece ser adaptada ao fogo, sugere-se que a presente área de campos de altitude é maior do que esperada sobre as condições climáticas atuais, especialmente em locais mais quentes em altitudes mais baixas. Além disso, estudos de mudanças climáticas preveem um clima mais quente e úmido durante o século 21, que provavelmente irá intensificar a migração da floresta atlântica para maiores altitudes, em detrimento da vegetação campestre. Nesta pesquisa, as relações passadas e presentes do mosaico de campos de altitude e florestas altomontanas (floresta com Araucária e floresta Atlântica nebular) são exploradas por meio de análises palinológicas. Inicialmente, foi investigada a correlação atual entre cobertura vegetal e produção de pólen. Observou-se que os taxa arbóreos são superestimados no conjunto de pólen de campos de altitude, constituindo uma área muito maior de captação de pólen do que no conjunto de pólen arbóreos. Sendo assim, o conjunto de pólen que caracteriza a vegetação de campos de altitude apresenta uma grande proporção de taxa de vegetação arbórea. Posteriormente, um sedimento de quase 10.000 anos foi analisado, demonstrando que, apesar dos taxa representantes da floresta altomontana estarem presentes na região de estudo durante todo o Holoceno, a vegetação florestal expandiu majoritariamente durante o Holoceno Tardio. Até cerca de 1350 cal a AP, a vegetação de campos de altitude ocupava áreas mais extensas. Em geral, os resultados demonstraram que o aumento de temperatura e precipitação ao longo do Holoceno favoreceram a migração da floresta para altitudes mais elevadas. Além disso, a pesquisa indicou que o fogo já estava presente na região antes da chegada dos primeiros humanos no Sudeste do Brasil, implicando na adaptação da vegetação campestre ao fogo. Por último analisou-se a dinâmica da vegetação nos últimos sete séculos. Os resultados indicaram que interferências antropogênicas como fogo, pastoreio e exploração madeireira desempenharam um importante papel na relação campos-floresta na Serra do Mar do Sudeste do Brasil. Com base nestes estudos, sugere-se que a manutenção do mosaico de campos de altitude e floresta no clima presente e futuro depende tanto de um manejo ativo quanto da mudança de foco da conservação de ambientes florestais para ambientes campestres.
322

ETSU Elevation Data - 1993

Johnson City GIS Division 01 January 1993 (has links)
Map of ETSU Elevation Data created by Johnson City GIS using 1993 contours. Map features listed on the bottom left corner includes major roads, ETSU structures, parks, and railroads. Physical copy resides with Johnson City, Geographic Information Systems Division. Scale: 5" = 2000 ft. / https://dc.etsu.edu/rare-maps/1050/thumbnail.jpg
323

Porovnání metod určování převýšení v experimentální síti Tetčice / The comparison of the method for the determination of height differencies in Tetčice experimental network

Povoda, Richard January 2012 (has links)
The subject of this thesis is comparation methods of measuring elevation of experimental points on the network site Tetčice. There was mutually comparated height differences , which were mesured with methods of precise leveling, trigonometric method and fast static GPS measurment method. It was experimentaly used Sanchez method to reduce the effects of refraction measured at zenith angles. In the area of interest was used the method of interpolation to height calculation of point Bučín in elevation system Bpv, calculated from quasi-geoid heights on the surrounding leveling points.
324

Development of regional exploration techniques for groundwater resources in semiarid areas through integration of remote sensing and geophysical survey / リモートセンシングと物理探査の統合による半乾燥地域での地下水資源の広域探査手法の開発

Luís, André Magaia 26 March 2018 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第21089号 / 工博第4453号 / 新制||工||1692(附属図書館) / 京都大学大学院工学研究科都市社会工学専攻 / (主査)教授 小池 克明, 教授 立川 康人, 准教授 後藤 忠徳 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM
325

From digitization to more administration? : How information systems affect routines and the distribution of administrative work

Nilsson, Alexander, Flink, Elina January 2023 (has links)
The healthcare sector is facing several challenges. One of them is that administrative tasks are being pushed into the core operation. This has led to a new concept arising, called “elevation”. This concept has not been analyzed from the field of information systems (IS) before, therefore the aim of the research is to investigate how the distribution of administrative work changes when introducing a new information system in the healthcare sector. To further understand the transformation brought by the introduction of a new IS, this study has also investigated the routine changes for healthcare staff. This study has been conducted using a case study with a regional government in Sweden. Hospital sites and the IT support function have been part of the case. The findings show that the new IS has digitized and slightly changed routine. Furthermore, the new IS has contributed to elevation. By making work easier, flexible and creating more shared responsibility, simpler, administrative tasks have been handed over to core staff. The research contributes to a deeper understanding of what happens to the distribution of administrated tasks when introducing a new IS.
326

Elevation Changes in Greenland over Two Decades from Cross-Platform LIDAR Analysis

Wheelock-Davis, Emily J. 08 August 2013 (has links)
No description available.
327

A Case of Anomalous Left Anterior Descending Artery Originating From the Right Sinus of Valsalva

Patel, Niravkumar, Bhogal, Sukhdeep, Ramu, Vijay, Helton, Thomas 01 June 2021 (has links)
The anomalous origin of coronary arteries has been extensively documented in the literature. Most of the anomalies are incidentally found either during coronary angiography or imaging studies and are usually benign; however, malignant outcomes have been reported in the literature. Here, we present the case of a 76-year-old male with non-ST segment elevation myocardial infarction who was found to have an asymptomatic anomalous origin left anterior descending artery from the right sinus of Valsalva.
328

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.
329

Framställning av digital höjdmodell för analys och visualisering av naturlik fiskväg : En tillämpning vid Strömdalens kraftverk, Gävle

Spånberg, Stefan January 2013 (has links)
Fiskvägar kan anläggas i anslutning till dammar för att överkomma de hinder som dammarna utgör mot migrerande fisk. En av de mest önskvärda lösningar som finns för detta är att anlägga naturlika fiskvägar, vilka har som syfte att efterlikna ett naturligt vattendrag. Ofta har dock dessa planerats för dåligt med avseende på exempelvis lutning och placering av ingången för att de ska kunna fungera riktigt effektivt. På grund av detta finns det behov av omfattande studier av topografi och kartering av området innan en fiskväg anläggs. I det här arbetet används topografin och de geografiska förutsättningarna för att studera möjliga sträckningar på en naturlik fiskväg förbi Strömdalens kraftverk i Gävle som en del av det fiskvandringsprojekt som Länsstyrelsen Gävleborg driver. I arbetet byggs en höjdmodell upp med hjälp av data från LiDAR (Light Detection and Ranging) och genom topografisk mätning, där mätpunkter från Global Navigation Satellite System (GNSS) och Totalstation används för att korrigera LiDAR-modellen över visst område. Det går att förbättra kvaliteten på modellen avsevärt med korrigering av LiDAR-data genom jämförelser mot mätpunkter. Studien har visat att det går att uppnå en noggrannhet som är bättre än en decimeter överlag i modellen, med vissa lokala variationer. Dessa variationer visar sig i större osäkerhet i mera svårdefinierad terräng, som strandkanter eller där terrängen visar stor variation. Studierna har också visat att i områden där det finns många mätpunkter är kvaliteten bättre än i områden där det är glest mellan punkterna. Bottentopografier hade varit mycket önskvärt att mäta eftersom dessa behövs vid fiskvägsplanering, men det var dessvärre vid tidpunkten för fältarbetet inte möjligt att utföra några mätningar i vattnet på grund av högt vattenstånd. I studien har också den uppbyggda höjdmodellen använts för att hitta metoder att analysera och visualisera olika förslag på naturlika fiskvägar. Studierna har visat att topografin är en viktig faktor inom planeringen på grund av fiskvägars lutningskrav. För att uppnå den önskade medellutningen måste i många fall topografin modifieras ordentligt och detta har visat sig vara ett problem vid Strömdalens kraftverk. Genom att utnyttja 3D-modellering går det se detta ur ett annat perspektiv och då framkommer också svårigheterna med att anpassa fiskvägen till terrängen bättre. / Dams are obstacles for migrating fish species and a solution for this problem is to construct fish bypasses. One of the most desirable solutions for this is nature-like fish passages which is a solution where the bypass is looking like a real stream. However, because these passages have been planned poorly considering slope and placing of the entrance, they have not been that effective. Because of that, studies in topography and mapping of the area are important before a fish passage is constructed. In this study the topographic and geographic criteria are used to study possible paths where the fish passage can be constructed. This is done around Strömdalens kraftverk, close to the central parts of Gävle as part of the fish migration project of Länsstyrelsen in Gävleborg. In the study, Digital Elevation Models (DEM) is produced by data from Light Detection and Ranging (LiDAR) and by performing a topographic survey using Global Navitation Satellite System (GNSS) and total station in this area. The LiDAR data are corrected by those survey points by comparing them to the uncorrected LiDAR model. By doing that and also including the survey points, the performance of the model was greatly improved. In general the surveyed area is shown to have an uncertainty lower than a decimeter, but with local variations. Those variations are higher in more complex terrain, for example around shorelines and in areas with high terrain variation. The study has also shown that the uncertainty is lower in areas where many points have been surveyed. Bathymetric data are of great importance. However, by the time of the field survey, it was impossible to perform any survey in the water because of a high water level. Different suggestions on nature-like fish paths have also been analyzed and visualized by using a produced DEM. The studies have shown that topography is a very important factor because of the slope criteria for those fish passages. To reach the desired mean slope the topography has to be greatly modified, which is a major issue near Strömdalens kraftverk. By using 3D models it is possible to see that from a different perspective and it's easier to see the difficulties to adapt the fish passage to the terrain.
330

Analysis of Habitat Fragmentation and Ecosystem Connectivity within The Castle Parks, Alberta, Canada

Beaver, Breanna, beaver January 2017 (has links)
No description available.

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