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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.
391

Produtividade do Eucalyptus sp. em função do estado nutricional e da fertilidade do solo em diferentes regiões do Estado de São Paulo. / Eucalyptus sp. in function of nutrient status and soil fertility in three regions of the state of São Paulo, Brazil.

Sgarbi, Fábio 17 May 2002 (has links)
Grande parte dos plantios de Eucalyptus sp., no Estado de São Paulo, apresentam limitações nutricionais as quais comprometem o crescimento e a sustentabilidade das florestas ao longo dos ciclos. Isso se deve a elevada exportação de nutrientes, durante a colheita da madeira associada a baixa fertilidade dos solos e a insuficiente utilização insumos, nestas áreas. Através de metodologias clássicas, é possível monitorar estes plantios visando a identificação dos nutrientes e dos parâmetros químicos do solo mais limitantes para o crescimento do Eucalyptus sp. Neste estudo, foram levantadas três regiões no Estado de São Paulo (Capão Bonito, Jacareí e Lençóis Paulista), durante os anos de 1997 a 2000. Para tanto, foram amostradas 209 parcelas, 117 talhões e 21 fazendas, totalizando 2.215 ha. As florestas estaram 12 a 45 meses de idade. Em cada talhão, foram locadas parcelas contendo 25 a 50 plantas, nas quais foram realizadas medições de altura das árvores visando a determinação do índice de sítio, assim como, amostragem de folhas e de solo, visando a determinação dos teores foliares dos nutrientes e dos parâmetros químicos do solo. Posteriormente, foi feita a análise dos dados através do método do nível crítico, das análises de correlação e de regressão linear e através do sistema integrado de diagnose e recomendação (DRIS). Verificou-se que os nutrientes mais limitantes para o crescimento do Eucalyptus sp. foram: boro, fósforo, nitrogênio e excesso de cobre nas regiões de Capão Bonito e Jacareí; o excesso de manganês, nas regiões de Jacareí e Lençóis Paulista; magnésio, potássio e o excesso de cálcio, na região de Lençóis Paulista. / Eucalyptus sp. stands, in the state of São Paulo, Brazil, present some nutrient limitations that can implicate growth and sustainability of the forests in the future. It happens because of high nutrient exportation during timber harvesting and also because of the low soil fertility and insufficient use of fertilizers in these areas. Through classic methodologies, the identification of the limiting nutrients is possible to monitor these stands and to determine the nutrient and the chemical parameters that limiting the growth. It were surveyed three regions of the state of São Paulo (Capão Bonito, Jacareí and Lençóis Paulista), during the years of 1997 to 2000. Data were collected in 209 sample plots, in 117 stands of 21 farms, totalizing 2.215 ha. The ages surveyed varied from 12 to 45 months old. Sample plots had 25 and 50 trees, that we measured total height for site index estimation (base age 7 years). Leaf and soil samples were collected to determine the nutrient content in the leaves and the soil chemical nutrients. Data were analyzed based in the method of the critical level, analyses of correlation and linear regression and through the diagnose and recommendation based on integrated system (DRIS). It was verified that the nutrients that limit Eucalyptus sp. growth were: boron, phosphorus, nitrogen and high copper content in Capão Bonito and Jacareí regions; the high manganese content in Jacareí and Lençóis Paulista regions and high calcium content, along with low magnesium and potassium content in the Lençóis Paulista region.
392

O constituinte-QU in situ no português brasileiro infantil / The constituent-Wh in situ in child Brazilian Portuguese

Vieira, Clariana Lara 28 June 2018 (has links)
Este trabalho tem como tema a aquisição do constituinte-QU in situ por crianças adquirindo o Português Brasileiro (doravante PB). Tal construção é encontrada em outras línguas também e, de modo análogo ao PB, é aparentemente opcional no Espanhol e no Francês. Realizando um paralelo entre os estudos de outras línguas e o PB, analisamos a frequência da construção na fala infantil no PB, comparada à fala adulta, e, principalmente, os contextos que favorecem sua produção, em oposição à contraparte movida. Para tanto, utilizamos uma metodologia experimental que elicia perguntas em contextos sem e com Common Ground (informação previamente compartilhada) e com priming sintático (fenômeno em que a exposição a uma sentença facilita o processamento de uma outra sentença com estrutura igual ou similar), com o objetivo de verificar em quais contextos a produção de QU-in situ é facilitada. Além disso, observamos também a escolha da estratégia de pergunta diante da influência exercida pelo estatuto do elemento-QU (como adjunto ou argumento). Os resultados das análises quantitativas sugerem que, na fala infantil, há um favorecimento do QU-in situ em contextos de Common Ground. Também ficou clara a influência do priming sintático na fala de ambos os grupos, infantil e adulto. Podemos dizer, então, que a metodologia obteve sucesso na eliciação da construção estudada e evidenciou que as perguntas com QU-in situ e QU-movido, embora aparentemente opcionais, não são intercambiáveis, já que o primeiro tipo de pergunta ocorreria na fala infantil apenas em um contexto pragmático específico. / This study explores the acquisition of Wh-questions in which the whconstituent remains in situ by children acquiring Brazilian Portuguese (henceforth BP). Such construction is found in other languages as well and, like in BP, it is optional in Spanish and in French. Drawing a parallel between the studies of other languages and BP, we analyze the frequency of the construction in child speech, compared to the adult speech, and, most importantly, the contexts that favor its production, in opposition to its moved counterpart. In order to do so, we used an experimental methodology that elicits questions in contexts with and without Common Ground (previously shared information) and contexts with syntactic Priming (phenomenon in which the exposure to an utterance facilitates the processing of another utterance with the same or similar structure), with the purpose of checking which contexts facilitate the production of Wh-in situ. Besides that, we also investigated the choice of question strategy in face of the influence imposed by the status of the wh-element (as adjunct or argument). Results of the quantitative analyses suggest that, in child speech,Wh-in situ is favored in contexts of Common Ground. It also has been clear that theres an influence of the syntactic Priming in both adult and child speech. Therefore, we point out that the methodology was successful in eliciting Wh-in situ questions and has made it clear that Wh-in situ and moved Wh, although apparently optional, are not interchangeable, since the first one is bound to a specific pragmatic context in child speech.
393

Um estudo sobre a equação de Hénon / A sudy on the Héenon equation

Quispe, Maribel Rosa Bravo 25 February 2013 (has links)
Este trabalho apresenta um estudo quantitativo e qualitativo de soluções positivas para o problema de Dirichlet para a equação de Hénon (P) { - \'DELTA\'u = \'Ix! POT. \' alpha\'\' \'IuI POT. p-2\' em B, u = sobre \\partial B, onde B é a bola unitária aberta de \'R POT. N\' centrada em zero e \'alpha\' > 0. É mostrado que para p \'> OU =\' \'2 AST\' \'IND. \'alpha\'\' = { \'SUP. 2(N + \'alpha)\' \' INF. N - 2\' ; N > 2, \"INFINITO\'; N = 1,2 \'2 AST\' = { \'SUP. 2N\' \'INF. N - 2\' ; N > 2, \'INFINITO\'; N = 1,2, o problema não tem solução não trivial. Em contrapartida, para 1 < p < \'2 AST\'.\' \'IND. \'alpha\'\' com p \'DIFERENTE DE\' 2, a existência de uma solução positiva radial é garantida. Além disso, é provado a unicidade de solução positiva no caso em que 1 < p < 2. Também são apresentados resultados sobre a existência de soluções ground state quando 2 < p < \'2 AST\'. Nesse intervalo, é mostrado que qualquer solução ground state exibe a simetria Schwarz folheada e, no caso em que \'alpha\' é suficientemente grande, é provado que qualquer solução ground state não é radialmente simétrica. Por fim, é apresentado um resultado sobre a existência de múltiplas soluções positivas / This work presents a quantitative and qualitative study of positive solutions for the Dirichlet problem for the Hénon equation (P) (P) { - \'DELTA\'u = \'Ix! POT. \' alpha\'\' \'IuI POT. p-2\' in B, u = 0 on \\partial B, where B is the unit open ball in \'R POT. N\' centered at zero and \'alpha\' \'> OR =\' 0. It is shown that for p \' > OR =\' \'2 AST\' \'IND. alpha\' = \'SUP. 2 (N + alpha)\' INF. N - 2, N > 2, \' INFINITY\'; N = 1, 2, \'2 AST\' = { \'SUP. .2N INF. N - 2 ; N > 2; 1; \' INFINITY\', N = 1, 2; the problem does not have nontrivial solution. In counterpart, for 1 < p < \' 2 AST\' \'IND. alpha\' with p \' DIFFERENT\' 2, the existence of radial positive solutions will be guaranteed. Moreover, the uniqueness of positive solution is guaranteed as long as 1 < p < 2. In addition, results on the existence of ground state solutions are presented in case 2 < p < \'2 AST\'. In this interval, it is proved that any ground state solution exhibits the Foliated Schwarz symmetry and, in case \'alpha\' is sufficiently large, it is shown that the no ground state solution is radially symmetric. This works ends with a result on the existence of multiple positive solutions
394

O constituinte-QU in situ no português brasileiro infantil / The constituent-Wh in situ in child Brazilian Portuguese

Clariana Lara Vieira 28 June 2018 (has links)
Este trabalho tem como tema a aquisição do constituinte-QU in situ por crianças adquirindo o Português Brasileiro (doravante PB). Tal construção é encontrada em outras línguas também e, de modo análogo ao PB, é aparentemente opcional no Espanhol e no Francês. Realizando um paralelo entre os estudos de outras línguas e o PB, analisamos a frequência da construção na fala infantil no PB, comparada à fala adulta, e, principalmente, os contextos que favorecem sua produção, em oposição à contraparte movida. Para tanto, utilizamos uma metodologia experimental que elicia perguntas em contextos sem e com Common Ground (informação previamente compartilhada) e com priming sintático (fenômeno em que a exposição a uma sentença facilita o processamento de uma outra sentença com estrutura igual ou similar), com o objetivo de verificar em quais contextos a produção de QU-in situ é facilitada. Além disso, observamos também a escolha da estratégia de pergunta diante da influência exercida pelo estatuto do elemento-QU (como adjunto ou argumento). Os resultados das análises quantitativas sugerem que, na fala infantil, há um favorecimento do QU-in situ em contextos de Common Ground. Também ficou clara a influência do priming sintático na fala de ambos os grupos, infantil e adulto. Podemos dizer, então, que a metodologia obteve sucesso na eliciação da construção estudada e evidenciou que as perguntas com QU-in situ e QU-movido, embora aparentemente opcionais, não são intercambiáveis, já que o primeiro tipo de pergunta ocorreria na fala infantil apenas em um contexto pragmático específico. / This study explores the acquisition of Wh-questions in which the whconstituent remains in situ by children acquiring Brazilian Portuguese (henceforth BP). Such construction is found in other languages as well and, like in BP, it is optional in Spanish and in French. Drawing a parallel between the studies of other languages and BP, we analyze the frequency of the construction in child speech, compared to the adult speech, and, most importantly, the contexts that favor its production, in opposition to its moved counterpart. In order to do so, we used an experimental methodology that elicits questions in contexts with and without Common Ground (previously shared information) and contexts with syntactic Priming (phenomenon in which the exposure to an utterance facilitates the processing of another utterance with the same or similar structure), with the purpose of checking which contexts facilitate the production of Wh-in situ. Besides that, we also investigated the choice of question strategy in face of the influence imposed by the status of the wh-element (as adjunct or argument). Results of the quantitative analyses suggest that, in child speech,Wh-in situ is favored in contexts of Common Ground. It also has been clear that theres an influence of the syntactic Priming in both adult and child speech. Therefore, we point out that the methodology was successful in eliciting Wh-in situ questions and has made it clear that Wh-in situ and moved Wh, although apparently optional, are not interchangeable, since the first one is bound to a specific pragmatic context in child speech.
395

Use of Ground-Based Canopy Reflectance to Determine Radiation Capture, Nitrogen and Water Status, and Final Yield in Wheat

Ritchie, Glen L. 01 May 2003 (has links)
Ground-based spectral imaging devices offer an important supplement to satellite imagery. Hand-held, ground-based sensors allow rapid, inexpensive measurements that are not affected by the earth’s atmosphere. They also provide a basis for high altitude spectral indices. We quantified the spectral reflectance characteristics of hard red spring wheat (Triticum aestivum cv. Westbred 936) in research plots subjected to either nitrogen or water stress in a two year study. Both types of stress reduced ground cover, which was evaluated by digital photography and compared with ten spectral reflectance indices. On plots with a similar soil background, simple indices such as the normalized difference vegetation index, ratio vegetation index, and difference vegetation index were equal to or superior to more complex vegetation indices for predicting ground cover. Yield was estimated by integrating the normalized difference vegetation index over the growing season. The coefficient of determination (r2) between integrated normalized difference vegetation index and final yield was 0.86. Unfortunately, none of these indices were able to differentiate between the intensity of green leaf color and ground cover fraction, and thus could not distinguish nitrogen from water stress. We developed a reflective index that can differentiate nitrogen and water stress over a wide range of ground cover. The index is based on the ratio of the green and red variants of the normalized difference vegetation index. The new index was able to distinguish nitrogen and water stress from satellite data using wavelengths less than 1000 nm. This index should be broadly applicable over a wide range of plant types and environments.
396

Bergvärme som energikälla

Back, Natalii January 2008 (has links)
<p>2008-05-26</p><p>Bedrock heat as an energy source</p><p>The sun has warmed up the bedrock and this heat can be used for warming up houses. Approximately 100 – 200 meters down in the bedrock the temperature of the heat is stable. This is a source of energy that can be used by installing a heat pump system. The ground source heat pumps are low maintenance and can last for many years. There is also a pollution risk for the groundwater and therefore the wells in the area. Before the ground source heat pump can be installed the municipality need to give permission, according to the environmental code. To install the system without permission is a crime against the environmental code. A requirement when applying for permission to install the heat pump system is to get the neighbours to agree with the place for the bore hole. The neighbour can appeal against the environmental and health authorities’ decision to give permission to install the ground source heat pump system. However there needs to be more research done regarding the environmental effects that may occur in the future, if the ground source heatpump system continues to increase as rapidly as today.</p>
397

Räder och svensk doktrin samt reglemente för markoperationer?

Svensson, Magnus January 2009 (has links)
<p>NATO, USA, Storbritannien och Ryssland m.fl. använder sig av stridsuppgiften räd för markstridskrafter och erfarenheter från bl.a. Irakkriget 2003 visar att de kan få stor betydelse. Räder anses överensstämma med manöverteorin, men räder återfinns inte som stridsuppgift för svenska markstridskrafter.</p><p>Denna uppsats analyserar stridsuppgiften räd för markstridskrafter, operationaliserar två indikatorer för räder och med hjälp av dessa undersöks hur räder är förenligt med FM nuvarande doktrin och Reglemente för Markoperationer (RMO).</p><p>Undersökningen visar att räder inte är förenliga med nuvarande doktrin och RMO. Bl.a. så uppfattas det sakna överensstämmelse att avsiktligt inte bibehålla öppna landförbindelser. Däremot är delar av indikatorerna direkt eller indirekt att anse som förenliga.</p> / <p>NATO, USA, Great Britain and Russia are among others using the task raid for ground forces and experiences from e.g. the war in Iraq 2003 have shown that they could have great importance. Raids are considered to correspond to manoeuvre theory, but raids are not to be found as a task for Swedish ground forces.</p><p>This paper is analyzing the task raid for ground forces, developing two indicators for raids and with the help of these examining how raids are compatible with the armed forces present doctrine and field manual for ground operations.</p><p>The investigation shows that raids are not compatible with the present doctrine and field manual for ground operations. E.g. is it considered to disagree not to keep land lines of communications open. Parts of the indicators are however directly or indirectly considered compatible.</p>
398

Bergvärme som energikälla

Back, Natalii January 2008 (has links)
2008-05-26 Bedrock heat as an energy source The sun has warmed up the bedrock and this heat can be used for warming up houses. Approximately 100 – 200 meters down in the bedrock the temperature of the heat is stable. This is a source of energy that can be used by installing a heat pump system. The ground source heat pumps are low maintenance and can last for many years. There is also a pollution risk for the groundwater and therefore the wells in the area. Before the ground source heat pump can be installed the municipality need to give permission, according to the environmental code. To install the system without permission is a crime against the environmental code. A requirement when applying for permission to install the heat pump system is to get the neighbours to agree with the place for the bore hole. The neighbour can appeal against the environmental and health authorities’ decision to give permission to install the ground source heat pump system. However there needs to be more research done regarding the environmental effects that may occur in the future, if the ground source heatpump system continues to increase as rapidly as today.
399

Räder och svensk doktrin samt reglemente för markoperationer?

Svensson, Magnus January 2009 (has links)
NATO, USA, Storbritannien och Ryssland m.fl. använder sig av stridsuppgiften räd för markstridskrafter och erfarenheter från bl.a. Irakkriget 2003 visar att de kan få stor betydelse. Räder anses överensstämma med manöverteorin, men räder återfinns inte som stridsuppgift för svenska markstridskrafter. Denna uppsats analyserar stridsuppgiften räd för markstridskrafter, operationaliserar två indikatorer för räder och med hjälp av dessa undersöks hur räder är förenligt med FM nuvarande doktrin och Reglemente för Markoperationer (RMO). Undersökningen visar att räder inte är förenliga med nuvarande doktrin och RMO. Bl.a. så uppfattas det sakna överensstämmelse att avsiktligt inte bibehålla öppna landförbindelser. Däremot är delar av indikatorerna direkt eller indirekt att anse som förenliga. / NATO, USA, Great Britain and Russia are among others using the task raid for ground forces and experiences from e.g. the war in Iraq 2003 have shown that they could have great importance. Raids are considered to correspond to manoeuvre theory, but raids are not to be found as a task for Swedish ground forces. This paper is analyzing the task raid for ground forces, developing two indicators for raids and with the help of these examining how raids are compatible with the armed forces present doctrine and field manual for ground operations. The investigation shows that raids are not compatible with the present doctrine and field manual for ground operations. E.g. is it considered to disagree not to keep land lines of communications open. Parts of the indicators are however directly or indirectly considered compatible.
400

Fast Feature Extraction From 3d Point Cloud

Tarcin, Serkan 01 February 2013 (has links) (PDF)
To teleoperate an unmanned vehicle a rich set of information should be gathered from surroundings.These systems use sensors which sends high amounts of data and processing the data in CPUs can be time consuming. Similarly, the algorithms that use the data may work slow because of the amount of the data. The solution is, preprocessing the data taken from the sensors on the vehicle and transmitting only the necessary parts or the results of the preprocessing. In this thesis a 180 degree laser scanner at the front end of an unmanned ground vehicle (UGV) tilted up and down on a horizontal axis and point clouds constructed from the surroundings. Instead of transmitting this data directly to the path planning or obstacle avoidance algorithms, a preprocessing stage has been run. In this preprocess rst, the points belonging to the ground plane have been detected and a simplied version of ground has been constructed then the obstacles have been detected. At last, a simplied ground plane as ground and simple primitive geometric shapes as obstacles have been sent to the path planning algorithms instead of sending the whole point cloud.

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