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Degradation modeling and monitoring of engineering systems using functional data analysisZhou, Rensheng 08 November 2012 (has links)
In this thesis, we develop several novel degradation models based on techniques from functional data analysis. These models are suitable for characterizing different types of sensor-based degradation signals, whether they are censored at a certain fixed time point or truncated at the failure threshold. Our proposed models can also be easily extended to accommodate for the effects of environmental conditions on degradation processes. Unlike many existing degradation models that rely on the existence of a historical sample of complete degradation signals, our modeling framework is well-suited for modeling complete as well as incomplete (sparse and fragmented) degradation signals. We utilize these models to predict and continuously update, in real time, the residual life distributions of partially degraded components. We assess and compare the performance of our proposed models and existing benchmark models by using simulated signals and real world data sets. The results indicate that our models can provide a better characterization of the degradation signals and a more accurate prediction of a system's lifetime under different signal scenarios. Another major advantage of our models is their robustness to the model mis-specification, which is especially important for applications with incomplete degradation signals (sparse or fragmented).
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Sunkiasvorio transporto įtaka automobilių kelių asfaltbetonio dangos funkcionavimo trukmei / Impact of Heavy Weight Vehicles on Duration of Service Life of Asphalt Concrete Road PavementButkevičius, Saulius 04 December 2007 (has links)
Pastaraisiais metais Lietuvoje ženkliai padidėjęs sunkiasvorio transporto eismas sąlygoja ankstyvą daugumos šalies kelių dangų suirtį, nes jau nepakanka esamo jos stiprio. Įvairios asfaltbetonio dangos pažaidos rodo, kad ardoma ne tik danga, bet ir jos konstrukcija – tai didina išlaidas kelių remontui bei priežiūrai, mažėja eismo saugumas bei komfortiškumas. Iki šiol Lietuvoje dar nėra metodikos, kurią taikant būtų galima pakankamai tiksliai įvertinti sunkiasvorio transporto poveikį kelių dangai.
Šiame darbe ištirta sunkiasvorio transporto eismo ardomojo poveikio, įvertinant Lietuvos klimato sąlygas, įtaka kelių dangos asfaltbetonio sluoksnių stipriui ir funkcionavimo trukmei. Pateikta metodika sunkiasvorio transporto eismo ir apkrovų ardančio poveikio Lietuvos kelių dangai, priklausomai nuo eismo sezoniškumo, jos stiprio, asfaltbetonio sluoksnių likutinio stiprio bei kelių dangos įtempto-deformuoto būvio kitėjimo, įvertinti.
Pasiūlytas kelių dangos asfaltbetonio sluoksnių likutinio stiprio ir funkcionavimo trukmės likutinio resurso modelis. Modelis įvertina apkrovos parametrus bei jos poveikio intensyvumą, automobilių srauto sudėtį, kelių dangos sluoksnių medžiagų bei jai stiprinti naudojamų medžiagų projektines savybes, kelių dangos sluoksnio medžiagos stiprio kitėjimą, atsižvelgiant į jos suirties mastą, kelių dangos darbą, esant įvairioms vietovės klimato sąlygoms, skirtingiems žemės sankasos gruntams ir vietovės hidroterminiams rėžimams, remonto darbų kainą bei ekonominį... [toliau žr. visą tekstą] / The marked increase of heavy weight vehicle traffic in Lithuania in recent years is the reason for early deterioration of majority road pavements of the country due to inadequate strength of road pavements. Various kinds of damages in asphalt concrete pavements indicate that damage is made not only to a pavement but to its construction as well, which increases costs for road repair and maintenance and reduces road safety and comfort. There is no methodology in Lithuania that would allow to evaluate the impact of heavy weight vehicles on a road pavement with adequate preciseness.
This study analyses the impact of damaging effect of heavy weight vehicle traffic on the strength and duration of service life of asphalt concrete layers in a road pavement taking account of climate conditions of Lithuania. A methodology to evaluate the damaging effect of heavy weight vehicle traffic and loads on road pavements in Lithuania depending on seasonal peculiarities of traffic, its strength, remaining strength resource of asphalt concrete layers and changes in stressed or deformed state of a road pavement is presented.
A model of remaining strength of asphalt concrete layers in a road pavement and remaining resource of service life was proposed. The model evaluates load parameters and intensity of its impact, composition of vehicle flow, design characteristics of materials in layers of a road pavement and materials used when strengthening it, changes in the strength of layer material in a... [to full text]
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A new approach in survival analysis with longitudinal covariatesPavlov, Andrey 27 April 2010 (has links)
In this study we look at the problem of analysing survival data in the presence of
longitudinally collected covariates. New methodology for analysing such data has
been developed through the use of hidden Markov modeling. Special attention has
been given to the case of large information volume, where a preliminary data reduction
is necessary. Novel graphical diagnostics have been proposed to assess goodness of fit
and significance of covariates.
The methodology developed has been applied to the data collected on behaviors
of Mexican fruit flies, which were monitored throughout their lives. It has been found
that certain patterns in eating behavior may serve as an aging marker. In particular it
has been established that the frequency of eating is positively correlated with survival
times. / Thesis (Ph.D, Mathematics & Statistics) -- Queen's University, 2010-04-26 18:34:01.131
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Decomposição e liberação de nitrogênio da palha cana-de-açucar em função do ambiente e quantidade de palha / Decomposition and release of nitrogen fron sugarcane straw in relation to environment and quantity of strawDietrich, Guilherme 28 July 2014 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The sugarcane residues came out as an important source of biomass for the production of
cellulosic ethanol in Brazil. However, there is a lack of studies on the impact that how partial
removal of these residues affect the decomposition of the remaining crop residue on the soil
surface. In this context, the aim of this study was to evaluate the decomposition and release of
nitrogen (N) from sugarcane residues under field conditions. Three different rates of residues
were evaluated at five different location of the Rio Grande do Sul state, Brazil. The study was
conducted from September 2012 to August 2013, in the municipalities of Port Xavier, São
Luiz Gonzaga, Jacuí Heels, Santa Maria and Pelotas. The experimental design was completely
randomized with four replications. To monitor the process of decomposition, RB 956 911
sugarcane straw was air dried, and added in amounts equivalent to 4, 8 and 12 t ha-1 in
wooden boxes. These wooden boxes were then collected monthly over a period of one year.
The collected materials, was analyzed for the remaining amounts of dry matter (DM) and its
C and N concentrations. The straw collected in Santa Maria were also analyzed for
hemicellulose (HEM), cellulose (CEL) and lignin (LIG ) the values of DM and remaining C
was adjusted in non-linear regression model. The results of this study demonstrated that the
amount of sugarcane straw deposited on the surface does not affect the decomposition and
release of carbon and nitrogen, and also the breakdown of bio-chemicals (cellulose,
hemicellulose and lignin) in the straw. However, it was demonstrated that the site influenced
the decomposition and carbon and nitrogen release from the straw, with the main factor
controlling decomposition process was precipitation. / Os resíduos culturais da cultura da cana-de-açúcar se destacam como importante fonte
de biomassa para a produção do etanol celulósico no Brasil. No entanto, há uma carência de
estudos sobre o impacto que a retirada parcial desses resíduos causa na decomposição dos
resíduos culturais remanescentes na superfície do solo. Nesse contexto, o objetivo deste
estudo foi avaliar a decomposição e liberação de nitrogênio (N) dos resíduos culturais de
cana-de-açúcar em condições de campo em função de três diferentes quantidades de resíduos
e em cinco ambientes do estado do Rio Grande do Sul, Brasil. O estudo foi realizado no
período de setembro de 2012 a agosto de 2013, nos municípios de Porto Xavier, São Luiz
Gonzaga, Salto do Jacuí, Santa Maria e Pelotas. O delineamento experimental foi o
inteiramente casualizado, com 4 repetições. Para monitorar o processo de decomposição, a
palha da cana RB 956911, seca ao ar, foi colocado em quantidades equivalentes a 4, 8 e 12
Mg ha-1 em quadros de madeira telados, os quais foram depositados no interior do canavial e
recolhidas mensalmente durante um período de 360 dias. Nos materiais coletados, foram
feitas determinações das quantidades remanescentes de matéria seca (MS) e da sua
concentração de C e N. Na palha coletada em Santa Maria foram também determinados os
teores de hemicelulose (HEM), celulose (CEL) e lignina (LIG) Aos valores obtidos de MS e
C remanescentes foi ajustado modelo de regressão não linear. Os resultados deste estudo
demonstram que a quantidade de resíduos de cana-de-açúcar depositada na superfície do solo
não afeta a decomposição, liberação de carbono e nitrogênio, e também a decomposição dos
compostos bioquímicos (celulose, hemicelulose e lignina) presentes na palha. No entanto, foi
demonstrado que o local de estudo exerce influência na decomposição e liberação de carbono
e nitrogênio dos resíduos, sendo a precipitação o principal fator controlador do processo de
decomposição.
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Análise de critérios para definição da vazão remanescente em usinas hidrelétricas. / Analysis of criteria to the remaining flows definition in hydroelectric plants.Luciana de Deus Melo 01 April 2011 (has links)
Tem crescido a demanda por energia em todo o mundo. No Brasil, com o aquecimento da economia aumentam ainda mais as pressões. O parque gerador Brasileiro é fortemente baseado na geração hidrelétrica, que representa aproximadamente 77,6% da oferta de geração de eletricidade. Entre os impactos ambientais gerados pela construção de barragens e reservatórios de aproveitamentos hidrelétricos está a mudança do regime fluvial de jusante, a chamada vazão remanescente. Entre outros, esta vazão deve garantir as condições adequadas à sobrevivência e continuação das espécies e dos ecossistemas, associando as necessidades humanas, ambientais e as características de cada região. Tomou-se como objeto de análise dois estudos de caso, a pequena central hidrelétrica (PCH) Santa Gabriela, localizada no rio Correntes, na divisa entre os estados de Mato Grosso e Mato Grosso do Sul e a usina hidrelétrica (UHE) Batalha, situada no rio São Marcos, na divisa entre os estados de Minas Gerais e Goiás. Embora o assunto seja discutido amplamente pela comunidade técnica e acadêmica, não há ainda nos marcos legais Brasileiros associados, uma definição explícita de critérios ou limites para estabelecimento da vazão remanescente. Em geral, as legislações estaduais estabelecem valores máximos outorgáveis determinados a partir de percentuais da curva de permanência (Q90, Q95) ou da vazão mínima anual de sete dias de duração e tempo de recorrência de 10 anos Q7,10, garantindo consequentemente as vazões mínimas remanescentes. Essas metodologias implicam num único valor fixo para a vazão ao longo do ano, o que não condiz com a realidade do regime hidrológico natural. Estudos atuais apontam para um hidrograma ecológico, que represente a variação das vazões entre os meses de estiagem e cheia. Assim, a metodologia envolveu a comparação entre critérios de outorga utilizados em alguns estados Q90, Q95 e Q7,10 e métodos citados na literatura para estudo da vazão ecológica (Tennant, Texas, Vazão Base e Perímetro Molhado) e as Resoluções referentes à Declaração de Reserva de Disponibilidade Hídrica (DRDH) das usinas, que especificam a vazão remanescente nas fases de enchimento e operação, emitidas pela Agência Nacional de Águas (ANA). Observaram-se valores de vazões substancialmente diferenciados entre os seis métodos empregados. Cabe destacar, que representa um avanço a publicação do Manual de Estudos de Disponibilidade Hídrica para Aproveitamentos Hidrelétricos (ANA, 2009), que visa à padronização dos documentos para fins obtenção da DRDH e da outorga do uso do potencial de energia hidráulica em corpo de água de domínio da União. Assim, o empreendedor poderá propor e negociar a demanda hídrica para as necessidades ambientais com as autoridades competentes, o que deverá ser discutido em reunião técnica inicial que deverá contar com a participação da Agência Nacional de Energia Elétrica (ANEEL), ANA, órgão ambiental, empreendedor e a empresa responsável pelos estudos ambientais. / Worldwide, the demand for energy has been increasing. In Brazil, with the economy warming up in the last years, the demand for energy supply further increased. The Brazilian power generating facilities are heavily based on hydroelectric generation, which represents 77,6% of the total generated electricity. Among the environmental impacts caused by the construction of dams and reservoirs are the changes on downstream discharges, known as the remaining discharge. This discharge should ensure the appropriate conditions to the survival and perpetuation of ecosystems, linking human and wild life needs of each region. In this respect, two case studies are taken as object of analysis: (1) a small hydroelectric power plant Santa Gabriela, located in Correntes river, in the limits of Mato Grosso and Mato Grosso do Sul States; (2) the hydropower plant Batalha, in São Marcos river, in the limits of Minas Gerais and Goiás States. Although its been observed that this issue is widely discussed by technical and academic communities, no legal framework or an explicit definition, or criteria, or limit values has been identified for the establishment of the remaining discharge in hydroelectric power plant projects. Generally, values have been defined based on criteria adopted in states water use rights acts that define minimum discharge parameters based on time series frequency analysis such as Q90%, Q95% or Q7, 10. These methodologies imply on a single value discharge throughout the year, which does not reflect the variability of natural hydrological regime. Current studies lead to an, so called, ecological hydrogram, which would represent discharges variability during drought and flood periods. The methodology of analysis in which the discussion presented in this master dissertation was based, involved the comparison of values obtained by different water use rights criteria adopted in some states like Q90%, Q95% and Q7, 10 and, methods quoted in the literature to define the ecological discharge (Tennant, Texas, Base Flow and Wetted Perimeter), as well as National Water Agencys (ANA) declarations related to the Water Availability Reserve Statement (WARS) which specifies remaining dischargesflow for the reservoir filling and operating phases. It was observed that the application of the different methods in the two case studies resulted in significantly different values for the definition of the remaining discharge. However, its worth to note that the publication of the Guidelines for Water Availability Study for Hydroelectric Power Plants (ANA, 2009) that aims the standardization of documents to obtain WARS and granting the use of water for energy generation purposes in federal jurisdiction represents an advance in these matters. By that, the developer may propose and negotiate water demands for wild life needs with the involved authorities, which should be discussed in the initial technical meeting that will count on the National Electrical Energy Agency (ANEEL), ANA, the related environmental agency, the developer and the organization/agency responsible for the environmental studies.
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Prognostics and health management of power electronicsAlghassi, Alireza January 2016 (has links)
Prognostics and health management (PHM) is a major tool enabling systems to evaluate their reliability in real-time operation. Despite ground-breaking advances in most engineering and scientific disciplines during the past decades, reliability engineering has not seen significant breakthroughs or noticeable advances. Therefore, self-awareness of the embedded system is also often required in the sense that the system should be able to assess its own health state and failure records, and those of its main components, and take action appropriately. This thesis presents a radically new prognostics approach to reliable system design that will revolutionise complex power electronic systems with robust prognostics capability enhanced Insulated Gate Bipolar Transistors (IGBT) in applications where reliability is significantly challenging and critical. The IGBT is considered as one of the components that is mainly damaged in converters and experiences a number of failure mechanisms, such as bond wire lift off, die attached solder crack, loose gate control voltage, etc. The resulting effects mentioned are complex. For instance, solder crack growth results in increasing the IGBT’s thermal junction which becomes a source of heat turns to wire bond lift off. As a result, the indication of this failure can be seen often in increasing on-state resistance relating to the voltage drop between on-state collector-emitter. On the other hand, hot carrier injection is increased due to electrical stress. Additionally, IGBTs are components that mainly work under high stress, temperature and power consumptions due to the higher range of load that these devices need to switch. This accelerates the degradation mechanism in the power switches in discrete fashion till reaches failure state which fail after several hundred cycles. To this end, exploiting failure mechanism knowledge of IGBTs and identifying failure parameter indication are background information of developing failure model and prognostics algorithm to calculate remaining useful life (RUL) along with ±10% confidence bounds. A number of various prognostics models have been developed for forecasting time to failure of IGBTs and the performance of the presented estimation models has been evaluated based on two different evaluation metrics. The results show significant improvement in health monitoring capability for power switches. Furthermore, the reliability of the power switch was calculated and conducted to fully describe health state of the converter and reconfigure the control parameter using adaptive algorithm under degradation and load mission limitation. As a result, the life expectancy of devices has been increased. These all allow condition-monitoring facilities to minimise stress levels and predict future failure which greatly reduces the likelihood of power switch failures in the first place.
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Análise de critérios para definição da vazão remanescente em usinas hidrelétricas. / Analysis of criteria to the remaining flows definition in hydroelectric plants.Luciana de Deus Melo 01 April 2011 (has links)
Tem crescido a demanda por energia em todo o mundo. No Brasil, com o aquecimento da economia aumentam ainda mais as pressões. O parque gerador Brasileiro é fortemente baseado na geração hidrelétrica, que representa aproximadamente 77,6% da oferta de geração de eletricidade. Entre os impactos ambientais gerados pela construção de barragens e reservatórios de aproveitamentos hidrelétricos está a mudança do regime fluvial de jusante, a chamada vazão remanescente. Entre outros, esta vazão deve garantir as condições adequadas à sobrevivência e continuação das espécies e dos ecossistemas, associando as necessidades humanas, ambientais e as características de cada região. Tomou-se como objeto de análise dois estudos de caso, a pequena central hidrelétrica (PCH) Santa Gabriela, localizada no rio Correntes, na divisa entre os estados de Mato Grosso e Mato Grosso do Sul e a usina hidrelétrica (UHE) Batalha, situada no rio São Marcos, na divisa entre os estados de Minas Gerais e Goiás. Embora o assunto seja discutido amplamente pela comunidade técnica e acadêmica, não há ainda nos marcos legais Brasileiros associados, uma definição explícita de critérios ou limites para estabelecimento da vazão remanescente. Em geral, as legislações estaduais estabelecem valores máximos outorgáveis determinados a partir de percentuais da curva de permanência (Q90, Q95) ou da vazão mínima anual de sete dias de duração e tempo de recorrência de 10 anos Q7,10, garantindo consequentemente as vazões mínimas remanescentes. Essas metodologias implicam num único valor fixo para a vazão ao longo do ano, o que não condiz com a realidade do regime hidrológico natural. Estudos atuais apontam para um hidrograma ecológico, que represente a variação das vazões entre os meses de estiagem e cheia. Assim, a metodologia envolveu a comparação entre critérios de outorga utilizados em alguns estados Q90, Q95 e Q7,10 e métodos citados na literatura para estudo da vazão ecológica (Tennant, Texas, Vazão Base e Perímetro Molhado) e as Resoluções referentes à Declaração de Reserva de Disponibilidade Hídrica (DRDH) das usinas, que especificam a vazão remanescente nas fases de enchimento e operação, emitidas pela Agência Nacional de Águas (ANA). Observaram-se valores de vazões substancialmente diferenciados entre os seis métodos empregados. Cabe destacar, que representa um avanço a publicação do Manual de Estudos de Disponibilidade Hídrica para Aproveitamentos Hidrelétricos (ANA, 2009), que visa à padronização dos documentos para fins obtenção da DRDH e da outorga do uso do potencial de energia hidráulica em corpo de água de domínio da União. Assim, o empreendedor poderá propor e negociar a demanda hídrica para as necessidades ambientais com as autoridades competentes, o que deverá ser discutido em reunião técnica inicial que deverá contar com a participação da Agência Nacional de Energia Elétrica (ANEEL), ANA, órgão ambiental, empreendedor e a empresa responsável pelos estudos ambientais. / Worldwide, the demand for energy has been increasing. In Brazil, with the economy warming up in the last years, the demand for energy supply further increased. The Brazilian power generating facilities are heavily based on hydroelectric generation, which represents 77,6% of the total generated electricity. Among the environmental impacts caused by the construction of dams and reservoirs are the changes on downstream discharges, known as the remaining discharge. This discharge should ensure the appropriate conditions to the survival and perpetuation of ecosystems, linking human and wild life needs of each region. In this respect, two case studies are taken as object of analysis: (1) a small hydroelectric power plant Santa Gabriela, located in Correntes river, in the limits of Mato Grosso and Mato Grosso do Sul States; (2) the hydropower plant Batalha, in São Marcos river, in the limits of Minas Gerais and Goiás States. Although its been observed that this issue is widely discussed by technical and academic communities, no legal framework or an explicit definition, or criteria, or limit values has been identified for the establishment of the remaining discharge in hydroelectric power plant projects. Generally, values have been defined based on criteria adopted in states water use rights acts that define minimum discharge parameters based on time series frequency analysis such as Q90%, Q95% or Q7, 10. These methodologies imply on a single value discharge throughout the year, which does not reflect the variability of natural hydrological regime. Current studies lead to an, so called, ecological hydrogram, which would represent discharges variability during drought and flood periods. The methodology of analysis in which the discussion presented in this master dissertation was based, involved the comparison of values obtained by different water use rights criteria adopted in some states like Q90%, Q95% and Q7, 10 and, methods quoted in the literature to define the ecological discharge (Tennant, Texas, Base Flow and Wetted Perimeter), as well as National Water Agencys (ANA) declarations related to the Water Availability Reserve Statement (WARS) which specifies remaining dischargesflow for the reservoir filling and operating phases. It was observed that the application of the different methods in the two case studies resulted in significantly different values for the definition of the remaining discharge. However, its worth to note that the publication of the Guidelines for Water Availability Study for Hydroelectric Power Plants (ANA, 2009) that aims the standardization of documents to obtain WARS and granting the use of water for energy generation purposes in federal jurisdiction represents an advance in these matters. By that, the developer may propose and negotiate water demands for wild life needs with the involved authorities, which should be discussed in the initial technical meeting that will count on the National Electrical Energy Agency (ANEEL), ANA, the related environmental agency, the developer and the organization/agency responsible for the environmental studies.
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ABSORÇÃO DE FÓSFORO POR PLANTAS DE SOJA, COM O AUMENTO DO pH EM LATOSSOLOS ARGILOSOS / AVAILABILITY OF PHOSPHORUS IN TWO CLAYEY LATOSOILS AND ITS ACCUMULATION IN SOYBEAN AS A FUNCTION OF THE INCREASE IN PHViviani, Carlos Alberto 08 June 2006 (has links)
Made available in DSpace on 2016-02-26T12:59:38Z (GMT). No. of bitstreams: 1
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Previous issue date: 2006-06-08 / To take better advantage of the P applied along the year and of the soil residual by the adequate use of lime, especially in soils cultivated and manured for many years, may be an economically viable practice, as lime is much less expensive than phosphate fertilizers, which may imply important increment in the profit margin for the farmer. Two experiments
were carried out in green house at the College of Agricultural Sciences of the Federal University of Dourados, Dourados, State of Mato Grosso do Sul, Brazil, with the following
objectives: to evaluate the effect of the increase in the soils pH and application of phosphate fertilizers and lime in the sowing lines in clayey latosoils with high fertility levels, on the
availability of P in the soil and the accumulation of this element in soy bean plants ant to obtain values for the most adequate pH for the soy bean crop with respect to the absorption of P. The experimental design used was of randomized blocks, in 4x2x2 factorial scheme, with four repetitions, as follows: Four levels of pH (original pH of each soil 6.0, 6.5, and 7.0, in CaCl2 0,01 mol L-1), two doses of P (0 and 21.82 mg dm-3), and two doses of lime (0 and 100 mg dm-3) respectively for a red dystrophic Latosoil (LVd) from the southern highland plane, and red dystrophic Latosoil (LVdf) from Ponta Porã, in the State of Mato Grosso do Sul, Brazil. In each experimental unit (4,0 dm-3 vase), four cv.BRS 133 soy bean plants was grown up till flower emergence. The following was evaluated: weight of dry matter, content of
P in the aerial part of the plant and P remaining in the soil. The availability of P in the soil, evaluated by the content of P extract from the ion exchange resin, increased significantly with the pH of the soil. For the PVdf a significant interaction between pH and doses of P, was observed, with the P content of the soil increasing with pH and with the application of P. For LVd an interaction between pH and doses of lime applied in the sowing line was observed, and in its absence a tendency to an increase in the P content in the soil with pH
was observed. The P remaining in the soil was significantly reduced by the increase in pH in both soils. In both experiments with increase of the pH of the soil an increase in the production of dry matter and accumulation of P in the aerial part of the plant was observed. In clayey latosoils and with high P content the increase in pH increases the availability of phosphorus, leading to a higher production of soy bean dry matter / O melhor aproveitamento do P aplicado no ano e do residual do solo favorecido pelo uso adequado de calcário, especialmente em solos cultivados e adubados por muitos anos, pode ser uma prática economicamente viável, uma vez
que o calcário tem custo muito inferior aos adubos fosfatados, podendo significar importante incremento na margem de lucro do agricultor. Foram realizados dois experimentos em casa de vegetação da Faculdade de
Ciências Agrárias da Universidade Federal da Grande Dourados, com os seguintes objetivos: avaliar o efeito do aumento do pH do solo e da aplicação de adubo fosfatado e calcário na linha de plantio em dois latossolos argilosos, com elevados níveis de fertilidade, sobre a disponibilidade de P no solo e o acúmulo desse elemento em plantas de soja e obter valores de pH do solo mais adequados para a cultura da soja em relação à absorção de P. O delineamento experimental utilizado foi o de blocos casualizados, em esquema fatorial 4x2x2, com quatro repetições, sendo: quatro níveis de pH (pH original de cada solo, 6,0, 6,5 e 7,0, em CaCl2 0,01mol L-1), duas doses de P (0 e 21,82 mg dm-3) e duas doses de calcário
(0 e 100 mg dm-3), respectivamente para um Latossolo Vermelho distrófico (LVd) de Chapadão do Sul - MS e um Latossolo Vermelho distroférrico (LVdf) de Ponta Porã - MS. Em cada unidade experimental (vaso de 4,0 dm-3), cultivaram-se quatro plantas de soja cv. BRS 133 até a floração. Avaliou-se: peso da massa seca, teor e acúmulo de P na parte aérea; teor de P e P remanescente no solo. A disponibilidade de P no solo, avaliada pelos teores de P extraídos pela resina de troca iônica, aumentou significativamente com o pH dos solos. Para o LVdf houve interação significativa entre pH e doses de P, os teores de P no solo aumentaram com o pH e com a aplicação de P. Para o LVd houve interação entre pH e doses de calcário aplicado na linha de plantio, e na ausência desse houve tendência de aumento dos teores de P no solo com o pH. O P remanescente foi significativamente reduzido pelo aumento do pH em ambos os solos. Nos dois experimentos, com o aumento do pH do solo houve incremento na produção de massa seca e de P acumulado na parte aérea da soja. Em solos argilosos e com alto teor de P a elevação do pH aumenta a disponibilidade de P, proporcionando maior produção de massa seca de soja
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ABSORÇÃO DE FÓSFORO POR PLANTAS DE SOJA, COM O AUMENTO DO pH EM LATOSSOLOS ARGILOSOS / AVAILABILITY OF PHOSPHORUS IN TWO CLAYEY LATOSOILS AND ITS ACCUMULATION IN SOYBEAN AS A FUNCTION OF THE INCREASE IN PHViviani, Carlos Alberto 08 June 2006 (has links)
Made available in DSpace on 2016-02-26T12:59:18Z (GMT). No. of bitstreams: 1
CarlosAlbertoViviani.pdf: 236119 bytes, checksum: 3dcbb110fd6868afb511ae48c8ebdfbe (MD5)
Previous issue date: 2006-06-08 / To take better advantage of the P applied along the year and of the soil residual by the adequate use of lime, especially in soils cultivated and manured for many years, may be an economically viable practice, as lime is much less expensive than phosphate fertilizers, which may imply important increment in the profit margin for the farmer. Two experiments
were carried out in green house at the College of Agricultural Sciences of the Federal University of Dourados, Dourados, State of Mato Grosso do Sul, Brazil, with the following
objectives: to evaluate the effect of the increase in the soils pH and application of phosphate fertilizers and lime in the sowing lines in clayey latosoils with high fertility levels, on the
availability of P in the soil and the accumulation of this element in soy bean plants ant to obtain values for the most adequate pH for the soy bean crop with respect to the absorption of P. The experimental design used was of randomized blocks, in 4x2x2 factorial scheme, with four repetitions, as follows: Four levels of pH (original pH of each soil 6.0, 6.5, and 7.0, in CaCl2 0,01 mol L-1), two doses of P (0 and 21.82 mg dm-3), and two doses of lime (0 and 100 mg dm-3) respectively for a red dystrophic Latosoil (LVd) from the southern highland plane, and red dystrophic Latosoil (LVdf) from Ponta Porã, in the State of Mato Grosso do Sul, Brazil. In each experimental unit (4,0 dm-3 vase), four cv.BRS 133 soy bean plants was grown up till flower emergence. The following was evaluated: weight of dry matter, content of
P in the aerial part of the plant and P remaining in the soil. The availability of P in the soil, evaluated by the content of P extract from the ion exchange resin, increased significantly with the pH of the soil. For the PVdf a significant interaction between pH and doses of P, was observed, with the P content of the soil increasing with pH and with the application of P. For LVd an interaction between pH and doses of lime applied in the sowing line was observed, and in its absence a tendency to an increase in the P content in the soil with pH
was observed. The P remaining in the soil was significantly reduced by the increase in pH in both soils. In both experiments with increase of the pH of the soil an increase in the production of dry matter and accumulation of P in the aerial part of the plant was observed. In clayey latosoils and with high P content the increase in pH increases the availability of phosphorus, leading to a higher production of soy bean dry matter / O melhor aproveitamento do P aplicado no ano e do residual do solo favorecido pelo uso adequado de calcário, especialmente em solos cultivados e adubados por muitos anos, pode ser uma prática economicamente viável, uma vez
que o calcário tem custo muito inferior aos adubos fosfatados, podendo significar importante incremento na margem de lucro do agricultor. Foram realizados dois experimentos em casa de vegetação da Faculdade de
Ciências Agrárias da Universidade Federal da Grande Dourados, com os seguintes objetivos: avaliar o efeito do aumento do pH do solo e da aplicação de adubo fosfatado e calcário na linha de plantio em dois latossolos argilosos, com elevados níveis de fertilidade, sobre a disponibilidade de P no solo e o acúmulo desse elemento em plantas de soja e obter valores de pH do solo mais adequados para a cultura da soja em relação à absorção de P. O delineamento experimental utilizado foi o de blocos casualizados, em esquema fatorial 4x2x2, com quatro repetições, sendo: quatro níveis de pH (pH original de cada solo, 6,0, 6,5 e 7,0, em CaCl2 0,01mol L-1), duas doses de P (0 e 21,82 mg dm-3) e duas doses de calcário
(0 e 100 mg dm-3), respectivamente para um Latossolo Vermelho distrófico (LVd) de Chapadão do Sul - MS e um Latossolo Vermelho distroférrico (LVdf) de Ponta Porã - MS. Em cada unidade experimental (vaso de 4,0 dm-3), cultivaram-se quatro plantas de soja cv. BRS 133 até a floração. Avaliou-se: peso da massa seca, teor e acúmulo de P na parte aérea; teor de P e P remanescente no solo. A disponibilidade de P no solo, avaliada pelos teores de P extraídos pela resina de troca iônica, aumentou significativamente com o pH dos solos. Para o LVdf houve interação significativa entre pH e doses de P, os teores de P no solo aumentaram com o pH e com a aplicação de P. Para o LVd houve interação entre pH e doses de calcário aplicado na linha de plantio, e na ausência desse houve tendência de aumento dos teores de P no solo com o pH. O P remanescente foi significativamente reduzido pelo aumento do pH em ambos os solos. Nos dois experimentos, com o aumento do pH do solo houve incremento na produção de massa seca e de P acumulado na parte aérea da soja. Em solos argilosos e com alto teor de P a elevação do pH aumenta a disponibilidade de P, proporcionando maior produção de massa seca de soja
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Avaliação da qualidade física e fisiológica de sementes de espécies florestais nativas produzidas em plantios de restauração florestal e remanescentes naturais no estado de São Paulo / Evaluation of physical and physiological quality of seeds of native forest species grown in restoration plantations and remaining natural forest in São PauloDiana Consuelo Castillo Diaz 04 December 2013 (has links)
As sementes nas florestas são as responsáveis pela manutenção e perpetuação de comunidades vegetais através da regeneração e são insumo básico nos programas de recuperação e conservação de ecossistemas, por tanto, a qualidade fisiológica, física, sanitária e genética das sementes adquire um grande valor na produção de plântulas saudáveis e viáveis, visando a adaptabilidade e permanência de populações a longo prazo. Por tanto, objetivou-se conhecer e comparar a qualidade fisiológica de sementes de espécies florestais nativas produzidas em plantios de restauração florestal e em áreas de remanescentes naturais no interior do estado de São Paulo, a partir do potencial germinativo, teores de umidade e peso seco das sementes, para assim gerar informações sobre a influência das áreas reflorestadas e naturais sobre as características das sementes e se áreas reflorestadas podem ser possíveis fontes de coleta de sementes viáveis para produtores e viveiristas para futuros projetos de restauração. A coleta de sementes e frutos foi realizada em sete áreas plantadas e doze naturais em um raio menor a 50 km ao redor do município de Piracicaba, SP, no período de fevereiro e setembro de 2012. Foram selecionadas 12 espécies presentes nas duas áreas (remanescente e reflorestada) e coletados frutos de aproximadamente 10 matrizes de cada espécie para posteriormente realizar testes de umidade e germinação. Os frutos foram beneficiados e as sementes armazenadas em geladeiras para sua conservação. O experimento foi instalado em condições controladas, utilizando gerbox e vermiculita como substrato e foram avaliados três vezes por semana até atingirem a germinação constante. As variáveis resposta avaliadas foram: massa seca de sementes (MSS), porcentagem de germinação (%G), tempo médio de germinação (TMG) e Índice de Velocidade de Germinação (IVG). Os dados foram transformados, submetidos a uma análise de variância (ANOVA) e a teste de tukey a 1%. Os valores de massa seca de sementes e porcentagem de germinação diferiram estatisticamente entre as espécies e suas matrizes e revelaram a existência de interação significativa entre as espécies florestais e as procedências. Porém, não houve diferença significativa nos valores de tempo médio de germinação (Valor P = 0,8529) e o Índice de Velocidade de Germinação (Valor P = 0,2448) entre as procedências (natural e plantada). De acordo com os resultados a área natural (0,128 g de MSS, 59,5%G, 11,7 TMG e 3,08 IVG) apresentou os melhores valores com relação à plantada (0,100 g de MSS, 53,4%G, 12,1 TMG e 3,13 IVG). No entanto os resultados de germinação nas duas áreas foram acima de 50%, além de demonstrar que com relação ao tempo e velocidade de germinação não existe influência significativa dos ambientes sobre a qualidade das sementes produzidas resultando dados favoráveis para coletores de sementes, produtores de mudas e restauradores de ecossistemas. / The seeds in the forests are responsible for maintenance and perpetuation of plant communities through regeneration and are a basic input in recovery programs and ecosystem conservation, therefore the seed quality, physical health, and genetics of the seeds have a great value in the production of healthy and viable seedlings, aiming at adaptability and persistence of populations in the long term. With this in mind, this study aimed to know and compare the physiological quality of seeds of native forest species grown in restoration plantations and remaining natural forest areas in the state of São Paulo, from the germination potential, moisture content, and dry weight of seeds, thus generating information about the influence of natural forested areas on the characteristics of seeds and if reforested areas may be potential sources for viable seeds for producers and nurseries for future restoration projects. The collection of seeds and fruits was performed in seven restored areas and twelve remaining areas in a smaller radius of 50 km around the city of Piracicaba, SP, between February and September 2012. We selected 12 species present in the two areas (remnant and restored) and collected approximately 10 trees of each species for further testing of moisture and germination. The fruits were processed and seeds were stored in refrigerators for their conservation. The experiment was conducted under controlled conditions, using gerbox and vermiculite as substrate, and the seeds were evaluated three times a week until they reached constant germination. The following variables were evaluated: dry seed (MSS), germination percentage (G%), mean germination time (MGT) and Germination Speed Index (GSI). The data were transformed, and then subjected to an analysis of variance (ANOVA) and Tukey\'s test at 1%. The dry mass of seeds and germination percentage differed among species and trees of that species, and revealed the existence of significant interactions among species and provenances. However, no significant difference in the values of mean germination time (P-value = 0.8529) and Germination Speed Index (P-value = 0.2448) were found among the provenances (natural and restored). According to the results, the natural area (MSS 0.128 g, 59.5 %G, 11.7 MGT and 3.08 GSI) showed the best values compared to restored area (MSS 0.100 g, 53.4%G, 12.1 MGT and 3.13 GSI). However the results of germination in both areas were above 50%, and demonstrate that with regard to time and speed of germination there is not significant influence of the environment on seed quality resulting favorable information for seed collectors, seedling producers and restoring ecosystems.
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