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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.
201

Assessment of Methods for Monitoring Responses to River Restoration: Riverbed and Channel Form Changes

Tu, Denise Shao-Wai 06 1900 (has links)
xi, 54 p. : ill. (some col.) / On the Middle Fork John Day River (MFJD), a low gradient, meandering river in eastern Oregon, restoration includes engineered log structures intended to increase in-stream complexity and habitat diversity. Effects of log structures on riverbed topography can be captured through repeat topographic surveys, digital elevation model (DEM) of differencing (DoD), and aerial imagery. This study evaluates the (1) potential for remote sensing analysis, (2) effect of survey point density on DEMs, and (3) application of DoDs, in monitoring riverbed changes in the MFJD. An average point spacing and density finer than 0.50m and 1.25pts/m<super>2</super> captures riverbed complexities. Although elevation changes were expected to be minimal, DoDs revealed -0.9 to 0.5m elevation changes associated with log structure designs. Incorporating numerical thresholds into future monitoring survey methods will improve the modeling of MFJD riverbed surfaces. Monitoring riverbed changes through DoDs can inform improvements to future restoration design and the effectiveness of log structures. / Committee in charge: Patricia McDowell, Chairperson; Andrew Marcus, Member
202

Variações de área das geleiras da Colômbia e da Venezuela entre 1985 e 2015, com dados de sensoriamento remoto / Glaciers area variations in Colombia and Venezuela between 1985 and 2015, with remote sensing data

Rekowsky, Isabel Cristiane January 2016 (has links)
Nesse estudo foram mapeadas e mensuradas as variações de área, elevação mínima e orientação das geleiras da Colômbia e da Venezuela (trópicos internos), entre os anos 1985-2015. Para o mapeamento das áreas das geleiras foram utilizadas como base imagens Landsat, sensores TM, ETM+ e OLI. Às imagens selecionadas foi aplicado o Normalized Difference Snow Index (NDSI), no qual são utilizadas duas bandas em que o alvo apresenta comportamento espectral oposto ou com características bem distintas: bandas 2 e 5 dos sensores TM e ETM+ e bandas 3 e 6 do sensor OLI. Os dados de elevação e orientação das massas de gelo foram obtidos a partir do Modelo Digital de Elevação SRTM (Shuttle Radar Topography Mission – v03). Em 1985, a soma das áreas das sete geleiras estudadas correspondia a 92,84 km², enquanto no último ano estudado (2015/2016) esse valor passou para 36,97 km². A redução de área ocorreu em todas as geleiras analisadas, com taxas de retração anual variando entre 2,49% a.a. e 8,46% a.a. Houve retração das áreas de gelo localizadas em todos os pontos cardeais considerados, bem como, elevação da altitude nas frentes de geleiras. Além da perda de área ocorrida nas menores altitudes, onde a taxa de ablação é mais elevada, também se observou retração em alguns topos, evidenciado pela ocorrência de altitudes menores nos anos finais do estudo, em comparação com os anos iniciais. Como parte das geleiras colombianas está localizada sobre vulcões ativos, essas áreas sofrem influência tanto de fatores externos, quanto de fatores internos, podendo ocorrer perdas de massa acentuadas causadas por erupção e/ou terremoto. / In this study, glaciers located in Colombia and Venezuela (inner tropics) were mapped between 1985-2015. The area of these glaciers was measured and the variations that occurred in each glacier were compared to identify whether the glacier was growing or shrinking. The minimum elevation of the glaciers fronts and the aspect of the glaciers were analyzed. The glaciers areas ware obtained by the use of Landsat images, TM, ETM+ and OLI sensors. The Normalized Difference Snow Index (NDSI) was applied to the selected images, in which two bands were used, where the ice mass has opposite (or very different) spectral behavior: bands 2 and 5 from sensors TM and ETM+, and bands 3 and 6 from sensors OLI. The elevation and the aspect data of the glaciers were obtained from SRTM (Shuttle Radar Topography Mission – v03) Digital Elevation Model. In 1985/1986, the sum of the areas of the seven studied glaciers corresponded to 92.84 km², while in the last year analyzed (2015/2016), this value shrank to 36.97 km². The area shrinkage occurred in all the glaciers that were mapped, with annual decline rates ranging from 2.49%/year to 8.46%/year. It is also possible to observe a decrease of the ice covered in all aspects considered, as well as an elevation in all glaciers fronts. In addition to the area loss occurred at lower altitudes, where the ablation rate is higher than in higher altitudes, shrinkage in some mountain tops was also present, which is evidenced by the occurrence of lower maximum elevations in the final years of the study, when compared with the initial years. Considering that part of the Colombian’s glaciers are located on active volcanoes, these areas are influenced by external and internal factors, and the occurrence of volcanic eruption and/or earthquake can cause sharp mass losses.
203

Tradu??o, adapta??o e avalia??o psicom?trica da Prova Cognitiva de Legan?s em uma popula??o idosa brasileira com baixo n?vel de escolaridade

Caldas, Vescia Vieira de Alencar 21 February 2011 (has links)
Made available in DSpace on 2014-12-17T15:16:12Z (GMT). No. of bitstreams: 1 VesciaVAC_DISSERT.pdf: 343460 bytes, checksum: 86c45fe2d51f76156c9223f0097f90ed (MD5) Previous issue date: 2011-02-21 / Introdu??o: The scales of cognitive screening are important tools for early detection of dementia, creating the possibility of developing measures to slow this process and assist in the management of the disease. Objective: To validate the Legan?s Cognitive Test (Prueba Cognitive de Legan?s) (PCL) for cognitive screening in low educated elderly Brazilians. Methods: The study sample was composed of 59 elderly residents from the city of Santa Cruz, Brazil with low schooling levels. Reliability was analyzed with a 2-day interval between assessments, and concurrent validity was assessed using the Mini Mental State Examination (MMSE). Results: According to the PCL, the prevalence of dementia was 11.8%. The scale items showed a moderate to strong correlation between domains (p <0.01), and inter-rater reliability exhibited ICC = 0.81, 95% CI (0.72-0.88). Factor analysis resulted in two factors: memory and orientation. Interscale agreement was considered poor (k = - 0.02), supporting the hypothesis of an educational impact on final MMSE scores. Conclusion: The results suggest that PCL has acceptable levels of reliability for use in low educated elderly Brazilians / Introdu??o: As escalas de rastreio cognitivo s?o ferramentas importantes para detec??o precoce da dem?ncia, gerando a possibilidade de desenvolvimento de medidas que retardem esse processo e auxiliem no manejo da doen?a. Objetivo: Validar a Prova Cognitiva de Legan?s (PCL) para rastreio cognitivo em idosos brasileiros com baixo n?vel de escolaridade. M?todos: Utilizou-se uma amostra de 59 idosos residentes no munic?pio de Santa Cruz-RN, com baixo n?vel educacional. A confiabilidade foi analisada com intervalo de dois dias entre as avalia??es, e a validade concorrente foi avaliada atrav?s do Mini Exame do Estado Mental (MEEM). Resultados: De acordo com a PCL a preval?ncia de dem?ncia foi de 11,8%. Os itens da escala apresentaram correla??o de moderada ? forte entre os dom?nios (p<0,01), e a confiabilidade inter-examinador apresentou um ICC=0.81, IC 95% (0.72-0.88). A an?lise fatorial agrupou dois fatores interpretados como mem?ria e orienta??o. A an?lise de concord?ncia entre as escalas mostrou um kappa ruim, refor?ando a hip?tese de influ?ncia de escolaridade no escore final obtido no MEEM. Conclus?o: Os resultados sugerem que a PCL possui n?veis de confiabilidade aceit?veis para utiliza??o em idosos brasileiros com baixa escolaridade, minimizando o vi?s de escolaridade presente na maioria das escalas de avalia??o cognitiva
204

Variações de área das geleiras da Colômbia e da Venezuela entre 1985 e 2015, com dados de sensoriamento remoto / Glaciers area variations in Colombia and Venezuela between 1985 and 2015, with remote sensing data

Rekowsky, Isabel Cristiane January 2016 (has links)
Nesse estudo foram mapeadas e mensuradas as variações de área, elevação mínima e orientação das geleiras da Colômbia e da Venezuela (trópicos internos), entre os anos 1985-2015. Para o mapeamento das áreas das geleiras foram utilizadas como base imagens Landsat, sensores TM, ETM+ e OLI. Às imagens selecionadas foi aplicado o Normalized Difference Snow Index (NDSI), no qual são utilizadas duas bandas em que o alvo apresenta comportamento espectral oposto ou com características bem distintas: bandas 2 e 5 dos sensores TM e ETM+ e bandas 3 e 6 do sensor OLI. Os dados de elevação e orientação das massas de gelo foram obtidos a partir do Modelo Digital de Elevação SRTM (Shuttle Radar Topography Mission – v03). Em 1985, a soma das áreas das sete geleiras estudadas correspondia a 92,84 km², enquanto no último ano estudado (2015/2016) esse valor passou para 36,97 km². A redução de área ocorreu em todas as geleiras analisadas, com taxas de retração anual variando entre 2,49% a.a. e 8,46% a.a. Houve retração das áreas de gelo localizadas em todos os pontos cardeais considerados, bem como, elevação da altitude nas frentes de geleiras. Além da perda de área ocorrida nas menores altitudes, onde a taxa de ablação é mais elevada, também se observou retração em alguns topos, evidenciado pela ocorrência de altitudes menores nos anos finais do estudo, em comparação com os anos iniciais. Como parte das geleiras colombianas está localizada sobre vulcões ativos, essas áreas sofrem influência tanto de fatores externos, quanto de fatores internos, podendo ocorrer perdas de massa acentuadas causadas por erupção e/ou terremoto. / In this study, glaciers located in Colombia and Venezuela (inner tropics) were mapped between 1985-2015. The area of these glaciers was measured and the variations that occurred in each glacier were compared to identify whether the glacier was growing or shrinking. The minimum elevation of the glaciers fronts and the aspect of the glaciers were analyzed. The glaciers areas ware obtained by the use of Landsat images, TM, ETM+ and OLI sensors. The Normalized Difference Snow Index (NDSI) was applied to the selected images, in which two bands were used, where the ice mass has opposite (or very different) spectral behavior: bands 2 and 5 from sensors TM and ETM+, and bands 3 and 6 from sensors OLI. The elevation and the aspect data of the glaciers were obtained from SRTM (Shuttle Radar Topography Mission – v03) Digital Elevation Model. In 1985/1986, the sum of the areas of the seven studied glaciers corresponded to 92.84 km², while in the last year analyzed (2015/2016), this value shrank to 36.97 km². The area shrinkage occurred in all the glaciers that were mapped, with annual decline rates ranging from 2.49%/year to 8.46%/year. It is also possible to observe a decrease of the ice covered in all aspects considered, as well as an elevation in all glaciers fronts. In addition to the area loss occurred at lower altitudes, where the ablation rate is higher than in higher altitudes, shrinkage in some mountain tops was also present, which is evidenced by the occurrence of lower maximum elevations in the final years of the study, when compared with the initial years. Considering that part of the Colombian’s glaciers are located on active volcanoes, these areas are influenced by external and internal factors, and the occurrence of volcanic eruption and/or earthquake can cause sharp mass losses.
205

Análise dos processos erosivos na Bacia do Córrego do Meio - município de São Pedro (SP): estudo do desencadeamento das erosões / Analysis of the erosive processes at Córrego do Meio Wastershed - municipality of São Pedro - SP: study of erosion initiation

Monique de Paula Neves 27 April 2017 (has links)
No âmbito da geomorfologia pressupõe-se que existe uma relação entre declividade (S) e área de contribuição (A) que condiciona o escoamento superficial necessário para ocasionar o surgimento das erosões. A relação entre estes parâmetros pode ser expressa pelo índice S = aA-b, que representa o limiar crítico de desencadeamento das erosões. Implementando este índice no SIG, pode-se elaborar produtos cartográficos com a finalidade de reproduzir espacialmente as áreas críticas sujeitas a ocorrência das erosões. O presente trabalho teve por objetivo realizar um estudo sobre o desencadeamento das erosões lineares, utilizando técnicas de geoprocessamento para obtenção dos parâmetros A e S. A área em estudo compreende a Bacia do Córrego do Meio, localizada no município de São Pedro - SP, e apresenta uma área de 48,06 km². Os pontos de feições erosivas foram compilados de trabalhos realizados previamente na área, e também por meio do levantamento em imagens de satélites e ortofotos, totalizando 58 pontos de erosões. O modelo digital de elevação (MDE), mapa de área de contribuição e declividade foram elaborados em ambiente SIG, com diferentes pixels de saída, 2, 10 e 30 metros, e para processamento dos dados hidrológicos foram utilizados dois algoritmos: D8 e D-Infinity. Os parâmetros A e S foram calculados para cada uma das feições, analisadas de maneira integrada, e com base em características especificas como posição no relevo e profundidade dos canais. O tamanho do pixel de saída refletiu significativamente na obtenção dos parâmetros A e S, por isso, foram utilizados os modelos com resoluções maiores, pois corresponderam melhor às características da área. Em relação aos algoritmos de fluxo acumulado o D-Infinity apresentou dados mais condizentes com a topografia, e possibilitou o ajuste matemático do limiar crítico no gráfico S x A. O índice obtido a partir da análise integrada foi S = 0,060A-0,280, o índice para feições localizadas em encosta S = 0,0539A-0,412, e feições em drenagem S = 0,0748A-0,397. Além destes, foram obtidos outros índices específicos, determinados conforme a profundidade das feições (< 0,5; 0,5 a 1; 1 a 1,5 e > 1,5 m). A implementação dos índices no SIG possibilitou a elaboração das Cartas de Zoneamento de Áreas de Ocorrência de Erosão que apresentaram resultados consistentes, quando comparadas com outros produtos cartográficos, e podem orientar a ocupação adequada nestes locais, evitando a deflagração de novos processos. Apesar de ser um modelo de predição de erosão simples, os dados obtidos auxiliaram a compreensão dos mecanismos de desencadeamento, por isso, podem subsidiar as ações de planejamento ambiental, visando à recuperação das áreas comprometidas, com o intuito de minimizar os danos ambientais, e as perdas econômicas e sociais. / Considering the geomorphology aspects, it is assumed that there is a relationship between slope (S) and contributing area (A) which determines the runoff necessary for the onset of erosion. The relationship between the morphometric parameters can be expressed by the index S = aA-b which represents the topographic threshold for the onset of erosion. Implementing this index in the GIS, cartographic products can be performed with the purpose of reproducing spatially the critical areas subject to the erosion occurrence. The aim of this work is the study if the onset of gully erosions using geoprocessing techniques to obtain the parameters A and S. The study area is the watershed of the Córrego do Meio, located in São Pedro, São Paulo state, with an approximated area of 48.06 km². The erosion feature was compiled from previous study in the area and also through the survey on satellite images and orthophotographs, totalizing 58 erosion points. The digital elevation model (DEM), contribution area and slope were performed in GIS, with different output pixels, 2, 10 and 30 meters, and for the hydrological data processing, two algorithms were used: D8 and D-Infinity. The parameters A and S were calculated for each of the erosion feature, which were analyzed as a whole, and also based on the specific characteristics such as position in the landforms and depth of the channels. The size of the output pixel reflected significantly in obtaining the parameters A and S, therefore, models with higher resolutions were used because they better represent the characteristics of the area. In relation to the flow accumulation algorithms, D-Infinity presented more consistent data with the topography, and enabled the mathematical adjustment of the threshold in the S x A chart. The index obtained from the analysis of all erosion was S = 0.060A-0.280, the index for erosions located in hillside S = 0.0539A-0.412, and erosions in drainage S = 0.0748A-0.397. Besides these, other specific indices were determined, according to the depth of the channels (< 0.5, 0.5 to 1, 1 to 1.5 and > 1.5 m). The implementation of the indexes in the GIS made possible to perform the Zoning Map of Probable Erosion Areas, which showed consistent results when compared to other cartographic products and may direct suitable occupancy in these locations, so as to avoid the onset of new processes. Although it is a model for prediction of simple erosion, the obtained data helped to understand the mechanisms of the onset of the gully erosion, and therefore, can subsidize the actions of environmental planning, aiming at the recovery of the committed areas, with the aim of minimizing environmental damage and economic and social losses.
206

De har ingen koll på dem : Ett undervisningsexperiment om de och dem

Standar, Caroline, Bagler, Cornelia January 2011 (has links)
No description available.
207

Dom skriver rätt, dem skriver fel : En kvantitativ undersökning i felanvändandet av de och dem i text och frågan om talspråk bör tillåtas i skrift

Alm, Malin, Larsson, Jasmine January 2016 (has links)
I denna uppsats undersöks språkbruket av de/dem/dom hos svenska skolelever i årskurserna 4–6, 8–9 och i olika årskurser inom tre olika gymnasieprogram. 165 elever i grundskolan och gymnasiet har svarat på en enkät utformad för att undersöka kunskapen i distinktionen mellan de/dem. Vi undersöker och diskuterar vad resultaten kan komma att ha för betydelse för användningen av pronomenen och om det skulle vara fördelaktigt att införa ett enhetligt pronomen. Frågan om de och dem borde ersättas av dom har varit en diskussion sedan början av 1900-talet men har blivit än mer ifrågasatt sedan 1950-talet. Frågan diskuteras fortfarande och ännu har ingen lösning eller kompromiss tillämpats. I uppsatsen kommer olika kompromisser som föreslagits att redovisas.     I denna uppsats undersöks också vad skolans ansvar är när eleverna ska lära sig de skriftliga normerna, specifikt de/dem och hur språket kan komma att se ut om utbildningen fortsätter som den gör idag.
208

Distinct element modeling for fundamental rock fracturing and application to hydraulic fracturing / 粒状体個別要素法による岩石破壊現象の基礎的検討および水圧破砕の破壊過程に関する研究

Shimizu, Hiroyuki 23 March 2010 (has links)
Kyoto University (京都大学) / 0048 / 新制・課程博士 / 博士(工学) / 甲第15338号 / 工博第3217号 / 新制||工||1484(附属図書館) / 27816 / 京都大学大学院工学研究科社会基盤工学専攻 / (主査)教授 石田 毅, 教授 松岡 俊文, 教授 三ケ田 均 / 学位規則第4条第1項該当
209

Eulerian-Lagrangian Two Phase Debris Flow Model

Martinez, Cora E 13 November 2009 (has links)
The main objective of this work is to develop a quasi three-dimensional numerical model to simulate stony debris flows, considering a continuum fluid phase, composed by water and fine sediments, and a non-continuum phase including large particles, such as pebbles and boulders. Large particles are treated in a Lagrangian frame of reference using the Discrete Element Method, the fluid phase is based on the Eulerian approach, using the Finite Element Method to solve the depth-averaged Navier–Stokes equations in two horizontal dimensions. The particle’s equations of motion are in three dimensions. The model simulates particle-particle collisions and wall-particle collisions, taking into account that particles are immersed in a fluid. Bingham and Cross rheological models are used for the continuum phase. Both formulations provide very stable results, even in the range of very low shear rates. Bingham formulation is better able to simulate the stopping stage of the fluid when applied shear stresses are low. Results of numerical simulations have been compared with data from laboratory experiments on a flume-fan prototype. Results show that the model is capable of simulating the motion of big particles moving in the fluid flow, handling dense particulate flows and avoiding overlap among particles. An application to simulate debris flow events that occurred in Northern Venezuela in 1999 shows that the model could replicate the main boulder accumulation areas that were surveyed by the USGS. Uniqueness of this research is the integration of mud flow and stony debris movement in a single modeling tool that can be used for planning and management of debris flow prone areas.
210

De bortglömda urfolken : En kritisk diskursanalys om samernas och den nordamerikanska ursprungsbefolkningens framställning i svenska historieläroböcker

Swärd, Ida January 2020 (has links)
Syftet med studien är att undersöka hur samerna respektive den nordamerikanska ursprungsbefolkningen framställs i samtida historieläroböcker för gymnasiets senare historiekurser. Det som undersökts är hur de två ursprungsfolkens historia och kulturmöten framställs i relation till vad som står i Gy11:s läroplan. Den använda metoden är Norman Faircloughs kritiska diskursanalys integrerat med Homi Bhabhas postkoloniala teori. Faircloughs metod belyser maktförhållanden i texten och Bhabhas teori klarlägger hur dessa maktförhållanden ter sig. Resultatet visar att det förekommer maktdiskurser i samtliga undersökta läroböcker. I vissa av böckerna finns ett tydligt ”vi och dem” perspektiv, där de två ursprungsfolken framställs som ”dem”. När urfolken väl nämns i läroböckerna nämns de kort och utan vidare problematisering, vilket gör att eleverna inte ges den kunskap om ursprungsfolk som läroplanen uttrycker. Dessutom nämns de alltid i relation eller åtskillnad från nationalstaten, aldrig enskilt. Resultatet överensstämmer med tidigare forskning inom området, vilket tyder på att varken samernas eller den nordamerikanska ursprungsbefolkningen ges något vidare utrymme i den svenska historieskrivningen på gymnasiet.

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