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Control of marine plankton respiration : High temperature sensitivity at low temperatures influenced by substrate availabilityAmundsson, Katharina January 2016 (has links)
Temperature dependence of marine plankton respiration is an important factor in understanding the function and changes in the ecosystem of the ocean. The aim of this study is to test the temperature sensitivity (Q10) of plankton respiration. The oxygen optode method was used to measure plankton respiration. Natural water samples from the Baltic Sea was incubated at short (in situ +1, +2, +3°C) and long (in situ +5, +10, +20°C) temperature intervals with influence of dissolved organic matter (DOC). The Arrhenius equation and Q10-model was used to determine the temperature dependence (Q10) of respiration at different temperatures. There was a significant difference in Q10 between short temperature intervals at low temperatures (p=0,008) and long temperature intervals at higher temperatures. There was no significant difference between long and short temperature intervals when DOC was added (p=0,094). A significant effect could be seen with the DOC enrichment at low temperatures, where the Q10-values became significantly lower (p=0,002) after DOC addition. This effect could, however, not be seen at higher temperatures (p=0,117). Together with results from earlier studies it was concluded that the difference in temperature depends on the actual temperature and not the length of the interval. Lowered temperature dependence at raised DOC concentration, was the opposite of what was expected. The results suggest that the importance of temperature for CO2 emissions and development of hypoxia in the sea may have been underestimated.
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Capacity Constraints for Air Traffic Flow DevelopmentPetersen, Rebecca January 2018 (has links)
In aviation, the demand for air traffic grows at a higher rate than the capacity. As the demand is predicted to continue to grow also in the future, so is the problem of capacity shortage. If the capacity cannot match the demand, it will result in congestion and delay. There are numerous factors that limit the capacity both on airside and landside, for example the runway capacity, noise restrictions, the environment surrounding the airport etc. Actors such as airlines, ground service companies, ICAO and IATA also affect and are affected by the available capacity. When planning opening of new airports or in case of changes in the location and size of the airports, the requirement for, as well as the currently available capacity must be examined. Previous studies regarding key limiting factors to air traffic capacity, address different constraints, but lack a comprehensive view. A compilation of air traffic constraints would therefore be a valuable tool in airport planning when capacity demand changes. The aim of this thesis was to identify key limiting factors and see how they affect air traffic. This thesis analyses the importance of different limiting factors in respect to the level of significance to which previous research has acknowledged the different constraints. To compliment the literature review, professionals in airport planning were interviewed. The result from the literature review as well as the interviews showed that the major limiting factor to air traffic capacity is the runway. The runway was also the factor that was affecting as well was affected by other limiting factors. Previous literature considered wake vortex to be the second most important constraint whereas the interviewees considered stands to be the runner up limiting factor. In conclusion, this thesis showed that the runway is the most important limiting factor to air traffic capacity. The thesis also showed that different limiting factors are closely linked to each other. For an overall understanding of air traffic capacity constraints and how these constraints affect air traffic flow, it is essential to understand the interaction between the limiting factors.
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Factors limiting the regeneration of large-seeded hardwoods in the Upper Coastal Plain of South CarolinaRiley, Joseph Michael Jr. 05 November 2001 (has links)
To test factors limiting regeneration of large-seeded hardwoods in the Upper Coastal Plain of South Carolina, we planted one-year old bare root Quercus alba L. and Cornus florida L. seedlings in pine plantation understories and adjacent clearcuts. We hypothesized that soil moisture, light, and leaf and stem herbivory would have relatively strong effects on growth and survival during the first two years after planting. Next to each seedling, we measured five abiotic factors (soil carbon and moisture, gap light index (GLI), and available nitrogen and phosphorus). We also estimated percent stem and leaf herbivory and harvested seedlings after the second year to measure seedling growth. Survival was not significantly different between clearcut (62.9%) and understory (64.6%) treatments. Biomass growth was significantly greater (P<0.05) in the clearcuts for both species. All abiotic variables measured except soil carbon were greater in the clearcuts (P<0.05). Each seedling growth response was regressed against all variables using forward selection (P=0.15). Soil moisture significantly affected survival in 12.5% and biomass growth in 16.7% of the regressions. Light availability significantly impacted biomass growth in 8.3% of the regressions. Neither leaf nor stem herbivory frequently affected survival, but one or the other or both significantly influenced the biomass growth of seedlings in 41.5% of the regressions. Herbivory had the strongest impact on seedling responses. Neither water nor light was very influential for growth or survival responses. We conclude that hardwood restoration in the uplands of the Upper Coastal Plain is best accomplished by planting in recent clearcuts. / Master of Science
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Fatores motivadores e limitadores do alisamento de resultados (income smoothing) pelas empresas listadas na BovespaCarlin, Diego de Oliveira 31 August 2009 (has links)
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Previous issue date: 31 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Uma das formas de gerenciamento de resultados constantemente abordada na literatura é o Alisamento de Resultados (Income Smoothing), que representa uma redução da variabilidade dos resultados reportados, tornando-os mais estáveis ao longo do tempo. O objetivo deste estudo é verificar fatores capazes de influenciar esta prática, relacionados a motivações de mercado, motivações contratuais e motivações políticas e regulatórias, bem como possíveis fatores limitadores da mesma. Para tanto, investigou-se a ocorrência do alisamento de resultados em uma amostra de 141 empresas listadas na Bolsa de Valores de São Paulo (BOVESPA), abrangendo um período de análise de oito anos (2000 a 2007). O método utilizado para a identificação das empresas alisadoras foi aquele proposto por Eckel (1981), baseado na comparação entre o coeficiente de variabilidade da receita bruta e do lucro líquido da empresa. Após esta identificação, empregou-se análise univariada, por meio do teste ANOVA, para verificar a existência de diferenças / One form of earnings management that is constantly addressed in the literature is Income Smoothing, which constitutes a reduction in the variability of reported results, making them more stable over time. The aim of this study is to identify factors such as market-related, contractual, political and regulatory motivations which influence this practice, as well as any factors that may limit it. To this end, was investigated the occurrence of income smoothing in a sample of 141 companies listed on the São Paulo Stock Exchange (BOVESPA), over an eight-year analysis period (2000 to 2007). The method used to identify companies that practiced income smoothing was proposed by Eckel (1981), based on the comparison between the coefficient of variability of gross revenue and net profit of the company. Following identification, univariate analysis in the form of the ANOVA test was employed to verify the existence of significant differences in variables between groups of smoothers and non-smoothers firms. The test result
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Regeneração natural de Apuleia leiocarpa (Vogel) J.F. Macbr. em floresta manejada no estado do acre / Natural regeneration of Apuleia leiocarpa (Vogel) J.F. Macbr. in managed forest in the state of acreDomingos Neto, Victor Carlos January 2017 (has links)
In view of the difficulty of establishing the natural regeneration of Apuleia leiocarpa in
areas of natural forest without anthropic impact, it was decided to investigate the
conditions that favor and limit its development, with a view to the vulnerability of this
species in different typologies forest in which it occurs. For this reason, we evaluated
a forest area after two years of logging in the southwest of the Brazilian Amazon,
located in the municipality of Porto Acre, state of Acre. The population of A. leiocarpa
was characterized based on data from forest inventory pre-exploratory and, for better
understanding of the behavior of the species in the area, the species were grouped
in diametric class as the formula proposed by Sturges. The analysis of the spatial
pattern of the species in the area was evaluated using the function K to Ripley, even
at a distance of 500 meters, corresponding to half the lower side of the area. For
evaluation and determination of factors influence and limiting factors in its
development, we selected trees seed port with dbh greater than 80 cm and with
crowns, remnants of forest management and distributed in two different situations:
areas that have not been damaged the activities of forest management and areas with
damage caused by logging. For the evaluation of natural regeneration, from the
regrowth, were selected tree stumps, exploited in a random manner, distributed
throughout the UPA with the objective of sampling different situations postexploratory.
The remaining individuals from logging with dbh greater than 30 cm
have diametric distribution uneven, with the largest number of individuals in the
intermediate classes and are distributed spatially aggregated form. The mechanisms
of regeneration of the species Apuleia leiocarpa found were the plants originating in
the dispersal of seeds and regrowth of vegetative parts by means of
differentiation. The regenerantes of seminal origin are dependent on opening of
clearings and scarification of the soil to develop, they were distributed in classes of
height with an exponential negative and maximum height of two meters. The
development of the regrowth at two years of age was superior to that of origin, with
heights of up to eight meters and circumference at 10 cm from the base up to 15 cm,
demonstrating an efficient mechanism of regeneration of the species. / Diante da dificuldade de estabelecimento da regeneração natural de Apuleia leiocarpa
em áreas de floresta natural sem antropização, decidiu-se investigar quais as
condições que favorecem e limitam o seu desenvolvimento, tendo em vista a
vulnerabilidade dessa espécie nas diversas tipologias florestais em que ocorre. Para
isso, avaliou-se uma área de Floresta após dois anos da exploração madeireira no
sudoeste da Amazônia Brasileira, localizada no Município de Porto Acre, estado do
Acre. A população de A. leiocarpa foi caracterizada a partir dos dados do inventário
florestal pré-exploratório e, para melhor entendimento do comportamento da espécie
na área, as espécies foram agrupadas em classe diamétrica conforme a fórmula
proposta por Sturges. A análise do padrão espacial da espécie na área foi avaliada
através da Função K de Ripley, até a distância de 500 metros, correspondente à
metade do menor lado da área. Para avaliação e determinação dos fatores influentes
e limitantes no seu desenvolvimento, selecionou-se árvores porta sementes com dap
acima de 80 cm e com copas frondosas, remanescentes do manejo florestal e
distribuídas em duas situações distintas: áreas que não sofreram danos das atividades
do manejo florestal e áreas com danos causados pela exploração madeireira. Para a
avaliação da regeneração natural, oriunda da rebrota, foram selecionados tocos de
árvores, explorados de forma aleatória, distribuídos no decorrer de toda a UPA com o
objetivo de amostrar diferentes situações pós-exploratória. Os indivíduos
remanescentes da exploração madeireira com dap acima de 30 cm apresentam
distribuição diamétrica irregular, com o maior número de indivíduos nas classes
intermediárias e estão distribuídos espacialmente de forma agregada. Os mecanismos
de regeneração da espécie Apuleia leiocarpa encontrados foram banco de plantas
originário da dispersão de sementes e rebrota de partes vegetativas por meio de
diferenciação cambial. Os regenerantes de origem seminal são dependentes de
abertura de clareiras e da escarificação do solo para desenvolverem-se, eles
apresentaram distribuição em classes de altura com forma exponencial negativa e
altura máxima de dois metros. O desenvolvimento da rebrota aos dois anos de idade
foi superior ao de origem seminal, apresentando alturas de até oito metros e
circunferência a 10 cm da base de até 15 cm, demonstrando-se um eficiente
mecanismo de regeneração da espécie.
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Multi-sensor and data fusion approach for determining yield limiting factors and for in-situ measurement of yellow rust and fusarium head blight in cerealsWhetton, Rebecca L. January 2016 (has links)
The world’s population is increasing and along with it, the demand for food. A novel parametric model (Volterra Non-linear Regressive with eXogenous inputs (VNRX)) is introduced for quantifying influences of individual and multiple soil properties on crop yield and normalised difference vegetation Index. The performance was compared to a random forest method over two consecutive years, with the best results of 55.6% and 52%, respectively. The VNRX was then implemented using high sampling resolution soil data collected with an on-line visible and near infrared (vis-NIR) spectroscopy sensor predicting yield variation of 23.21%. A hyperspectral imager coupled with partial least squares regression was successfully applied in the detection of fusarium head blight and yellow rust infection in winter wheat and barley canopies, under laboratory and on-line measurement conditions. Maps of the two diseases were developed for four fields. Spectral indices of the standard deviation between 500 to 650 nm, and the squared difference between 650 and 700 nm, were found to be useful in differentiating between the two diseases, in the two crops, under variable water stress. The optimisation of the hyperspectral imager for field measurement was based on signal-to-noise ratio, and considered; camera angle and distance, integration time, and light source angle and distance from the crop canopy. The study summarises in the proposal of a new method of disease management through suggested selective harvest and fungicide applications, for winter wheat and barley which theoretically reduced fungicide rate by an average of 24% and offers a combined saving of the two methods of £83 per hectare.
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Perspektivvidgande diskussioner : En studie kring deliberativa samtal som aktivitet i vid vägledningGabrielsson, Henrik January 2018 (has links)
Idén bakom studien är sprungen ur tanken att hitta en aktivitet för studie- och yrkesvägledare där man i den vida vägledningen ges möjlighet att både arbeta med kunskap och värdegrundande arbete; skolans dubbla uppdrag. Det deliberativa samtalet blev den aktiviteten som kom att testas i denna studie och också det som blev syftet med studien. Vad jag ville undersöka var om elever upplever effekter i form av ökade kunskaper och ökad medvetenhet kring begränsningsfaktorn kön, vilket kan leda till ökad valkompetens och perspektivvidgning. Studien genomfördes som ett fältexperiment med en experimentgrupp och en kontrollgrupp där deliberativa samtal var den nyckelvariabel som testades. Genom ett kunskapsprov samt genom semistrukturerad intervju i en fokusgrupp har empiri samlats in och analyserats. Således begagnar sig studien både av kvalitativ samt kvantitativ ansats. Resultaten visar att deliberativa samtal är en gångbar pedagogisk metod att använda sig av i den vida vägledningen, främst kopplat till medvetandegörandet hos elever gällande rådande strukturella förhållanden vid val till gymnasiet. Detta eftersom elevernas perspektiv vidgas. Metoden har viss positiv inverkan på elevers självkännedom, vilket påverkar valkompetensen i positiv bemärkelse. Gällande ökande kunskaper är metoden inte sämre än andra pedagogiska metoder och för vissa till och med bättre. / The idea behind the study has sprung from the thought of finding an activity for career counselors, where you in school based guidance is provided with the opportunity to work with knowledge and value-based work; school's dual assignment. The deliberative conversation became the activity that was being tested in this study and also what became the purpose of the study. What I wanted to investigate was whether students experience effects in terms of increased knowledge and increased awareness about the gender as limitation factor, which could lead to increased career management skills and perspective enlargement. The study was conducted as a field experiment with an experimental group and a control group where deliberative conversations were the key variables that were tested. Through a knowledge test and through semistructured interviews in a focus group, empirics have been collected and analyzed. Thus, the study uses both qualitative and quantitative approaches. The results show that deliberative conversations are a viable educational method to use in school based guidance, primarily linked to make pupils aware of current structural conditions regarding their choice of further education. This is because the students' perspective is widened. The method has a certain positive impact on pupils' self-knowledge, which influences career management skills in a positive sense. Existing increasing knowledge, the method is not worse than other educational methods and for some even better.
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Fatores contributivos e fatores limitadores para negócios sociais no Brasil : um estudo exploratório nas regiões sul e sudesteJappe, Marcio Luis Miron January 2013 (has links)
O objetivo geral deste trabalho é identificar os fatores contributivos e os fatores limitadores para negócios sociais nas regiões Sul e Sudeste do Brasil, por meio do atingimento dos seguintes objetivos específicos: (a) descrever os principais modelos conceituais existentes para negócios sociais, identificando similaridades e diferenças; (b) identificar as percepções dos principais atores sobre negócios sociais nas regiões Sul e Sudeste do Brasil; e (c) desenvolver um framework com as principais dimensões de análise, fatores contributivos e fatores limitadores para negócios sociais. Foi realizada uma pesquisa exploratória, qualitativa de abordagem direta e de análise descritivo-interpretativa, em duas fases. Na primeira, com pesquisa documental, na segunda por meio de trinta e seis entrevistas semi-estruturadas com atores-chave para negócios sociais no Brasil – empreendedores, suas equipes e organizações apoiadoras. Os dados coletados foram analisados segundo a técnica de análise de conteúdo e os resultados são apresentados de forma descritiva e sintetizados no framework de análise. Foram identificados oito fatores contributivos e dezoito fatores limitadores, distribuídos em cinco dimensões de análise. / The main objective of this research is to identify the contributing and limiting factors for social businesses in the Brazilian South and Southeast regions. The specific objectives are: (a) to describe the key existing social business conceptual models, making explicit their similarities and differences; (b) to identify the perception of the main players in the field of social business in the Brazilian South and Southeast regions; and (c) to develop an analytical framework with the main analysis dimensions, contributing and limiting factor. It was a two phases exploratory research, qualitative with a direct approach, with descriptive-interpretative analysis. On the first phase, the focus was on a documental research, on the second, the focus was on thirty-six semi-structured interviews with the main players in the field – entrepreneurs, their teams, and supporting organizations. The collected data processed according to the content analysis technique, and the results are presented in descriptive format, being sintetized in the analytical framework. The result were eight contributing factors and eighteen limiting factors, spread across five analytical dimensions.
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Fatores contributivos e fatores limitadores para negócios sociais no Brasil : um estudo exploratório nas regiões sul e sudesteJappe, Marcio Luis Miron January 2013 (has links)
O objetivo geral deste trabalho é identificar os fatores contributivos e os fatores limitadores para negócios sociais nas regiões Sul e Sudeste do Brasil, por meio do atingimento dos seguintes objetivos específicos: (a) descrever os principais modelos conceituais existentes para negócios sociais, identificando similaridades e diferenças; (b) identificar as percepções dos principais atores sobre negócios sociais nas regiões Sul e Sudeste do Brasil; e (c) desenvolver um framework com as principais dimensões de análise, fatores contributivos e fatores limitadores para negócios sociais. Foi realizada uma pesquisa exploratória, qualitativa de abordagem direta e de análise descritivo-interpretativa, em duas fases. Na primeira, com pesquisa documental, na segunda por meio de trinta e seis entrevistas semi-estruturadas com atores-chave para negócios sociais no Brasil – empreendedores, suas equipes e organizações apoiadoras. Os dados coletados foram analisados segundo a técnica de análise de conteúdo e os resultados são apresentados de forma descritiva e sintetizados no framework de análise. Foram identificados oito fatores contributivos e dezoito fatores limitadores, distribuídos em cinco dimensões de análise. / The main objective of this research is to identify the contributing and limiting factors for social businesses in the Brazilian South and Southeast regions. The specific objectives are: (a) to describe the key existing social business conceptual models, making explicit their similarities and differences; (b) to identify the perception of the main players in the field of social business in the Brazilian South and Southeast regions; and (c) to develop an analytical framework with the main analysis dimensions, contributing and limiting factor. It was a two phases exploratory research, qualitative with a direct approach, with descriptive-interpretative analysis. On the first phase, the focus was on a documental research, on the second, the focus was on thirty-six semi-structured interviews with the main players in the field – entrepreneurs, their teams, and supporting organizations. The collected data processed according to the content analysis technique, and the results are presented in descriptive format, being sintetized in the analytical framework. The result were eight contributing factors and eighteen limiting factors, spread across five analytical dimensions.
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Fatores contributivos e fatores limitadores para negócios sociais no Brasil : um estudo exploratório nas regiões sul e sudesteJappe, Marcio Luis Miron January 2013 (has links)
O objetivo geral deste trabalho é identificar os fatores contributivos e os fatores limitadores para negócios sociais nas regiões Sul e Sudeste do Brasil, por meio do atingimento dos seguintes objetivos específicos: (a) descrever os principais modelos conceituais existentes para negócios sociais, identificando similaridades e diferenças; (b) identificar as percepções dos principais atores sobre negócios sociais nas regiões Sul e Sudeste do Brasil; e (c) desenvolver um framework com as principais dimensões de análise, fatores contributivos e fatores limitadores para negócios sociais. Foi realizada uma pesquisa exploratória, qualitativa de abordagem direta e de análise descritivo-interpretativa, em duas fases. Na primeira, com pesquisa documental, na segunda por meio de trinta e seis entrevistas semi-estruturadas com atores-chave para negócios sociais no Brasil – empreendedores, suas equipes e organizações apoiadoras. Os dados coletados foram analisados segundo a técnica de análise de conteúdo e os resultados são apresentados de forma descritiva e sintetizados no framework de análise. Foram identificados oito fatores contributivos e dezoito fatores limitadores, distribuídos em cinco dimensões de análise. / The main objective of this research is to identify the contributing and limiting factors for social businesses in the Brazilian South and Southeast regions. The specific objectives are: (a) to describe the key existing social business conceptual models, making explicit their similarities and differences; (b) to identify the perception of the main players in the field of social business in the Brazilian South and Southeast regions; and (c) to develop an analytical framework with the main analysis dimensions, contributing and limiting factor. It was a two phases exploratory research, qualitative with a direct approach, with descriptive-interpretative analysis. On the first phase, the focus was on a documental research, on the second, the focus was on thirty-six semi-structured interviews with the main players in the field – entrepreneurs, their teams, and supporting organizations. The collected data processed according to the content analysis technique, and the results are presented in descriptive format, being sintetized in the analytical framework. The result were eight contributing factors and eighteen limiting factors, spread across five analytical dimensions.
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