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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.
341

Aktivering av trafiksäkerhetskameror : En studie av kameraaktiveringens effekter på fordonshastigheter i Sverige / Activation of speed cameras : A study of the effects of camera activation on vehicle speeds in Sweden

Lundström, Josefine, Ruotsalainen, Juoni January 2008 (has links)
<p>During 2006 an estimated number of 150 persons are supposed to have been killed in road accidents caused by speed limit violations. Through Automatic traffic security control (ATK) the Swedish road administration (Vägverket) is working towards lowering the number of speed related accidents. By placing the speed cameras on roads they've managed to lower the average speed at those places. The enlargement of the number of speed cameras is based upon knowledge about for example how high the risk is for speed related accidents on the roads. The speed cameras always measure the speed in which every vehicle passes, but aren't constantly activated to register speed violations. Our purpose with this essay is consequently to explore possible relations between the activation of the speed cameras and the speed itself on the roads.We studied the average speed and the number of speed violations during 12 weeks evenly distributed in 2007. To see if the results would differ, we used two different response variables in the analysis.  Multiple linear regression was used to analyse the average speed, while Poisson regression was used in the analysis of the number of speed violations. An activated camera proved to cause a lowered average speed and fewer speed violations in three regions (Skåne, Mälardalen, Norr).To study the effect of maximized camera activation, an experiment in the region of Mälardalen was performed in the beginning of 2008. The result showed that maximized camera activation didn't decelerate the average speed, in stead the region's own activation policy seems to be more important for a lowered average speed. When the traffic flow rises the average speed decelerates while the number of speed violations also rises. During the study of commuter traffic we could see that the average speed is lower and there is fewer speed violations on commuter roads compared to normal traffic roads.</p> / <p>Under 2006 beräknas 150 personer ha omkommit i vägtrafikolyckor på grund av överskridna hastighetsgränser. Vägverket arbetar för att sänka dessa siffror bland annat genom att använda sig av Automatisk trafiksäkerhetskontroll (ATK). Genom att placera trafiksäkerhetskameror på sträckor har medelhastigheten på dessa sänkts. Trafiksäkerhetskamerorna mäter alltid hastigheten hos varje passerande fordon, men är inte konstant aktiverade för att registrera hastighetsöverträdelser. Nu vill man optimera kameraaktiveringen för att minska antalet ärenden utan att hanteringskapaciteten överskrids. Vårt syfte med uppsatsen är därför att undersöka möjliga samband mellan aktivering av trafiksäkerhetskameror och själva hastigheten på vägarna.Medelhastigheten och antalet överträdelser studerades under tolv veckor jämnt fördelade över år 2007. Analyserna gjordes med två olika responsvariabler för att se om resultaten skilde sig åt. Vi använde oss av multipel linjär regression för att analysera medelhastigheten, medan Poissonregression användes för antalet överträdelser. Det visade sig att en aktiv kamera gav upphov till sänkta medelhastigheter och färre hastighetsöverträdelser i tre regioner (Skåne, Mälardalen, Norr).För att studera effekten av maximal kameraaktivering utfördes ett experiment i region Mälardalen under början av 2008. Det visade sig att en maximal aktivering inte gav en sänkning av genomsnittshastigheterna, istället verkar regionens egen aktiverings-strategi ha större betydelse för sänkta genomsnittshastigheter.När fordonsflödet på alla sträckor ökar så minskar medelhastigheten medan antalet överträdelser ökar. För pendeltrafiksträckor är medelhastigheten lägre och det sker färre hastighetsöverträdelser än på normaltrafiksträckor.</p>
342

Förhållandet mellan COD och TOC i skogsindustriella avlopp / The relationship between COD and TOC inforest industrial wastewater

Johanna, Frid January 2015 (has links)
Under tillverkningsprocessen i massa- och pappersindustrin bildas avloppsflöden i flera olika steg. Ett av de miljöbelastande utsläppen utgörs av organiskt material. Organiskt material kan mätas som biokemisk syreförbrukning (BOD), kemisk syreförbrukning (COD) eller som totalt organiskt kol (TOC). Analys av COD inkluderar ofta miljöfarliga ämnen (till exempel kvicksilver). Naturvårdsverket har under flera år aviserat att analysen kan komma att förbjudas och därmed blir analys av TOC allt mer vanligt. EU:s referensgränsvärden anges dock i COD och design av reningsanläggningar utgår oftast från COD. Detta leder till att båda parametrarna kommer att fortsätta att vara aktuella. Med syftet att förbättra kunskapen om sambanden mellan COD och TOC för olika typer av avlopp inom massa- och pappersindustrin samlades jämförande serier över COD och TOC in från olika svenska bruk. Serierna analyserades med hjälp av regressions- och korrelationsanalys, för att sedan jämföras med medelvärdet av brukens COD/TOC faktorer (omvandlingsfaktorer). Studien innehöll även en del där information om analyser, förbehandlingar och övergången från COD till TOC samlades in genom intervjuer med personer ute på bruken. Som en avslutande del av projektet genomfördes ett laborativt arbete i mindre skala med främsta syfte att se hur konstant omvandlingsfaktorn var över tiden. Resultaten visade att korrelationen mellan COD och TOC ofta var hög men att omvandlingsfaktorn var beroende av typ av tillverkningsprocess och rening. Värdet på omvandlingsfaktorn varierade därför mycket mellan olika bruk och delströmmar. Bruk med tillverkningsprocesser som använder få kemikalier hade en mer lika omvandlingsfaktor sinsemellan än bruk med kemikaliekrävande processer. Dessutom gav en högre reningsgrad en lägre omvandlingsfaktor. Omvandlingsfaktorn föreföll varken påverkas av halten suspenderat material eller vara årstidsberoende. Dessutomvar den också relativt konstant över tiden. / The industrial production of pulp and paper generates wastewater in several different steps in the production chain. Organic material from the wastewater will have an impacton the surrounding environment. Biological oxygen demand (BOD), chemical oxygendemand (COD) and total organic carbon (TOC) are three ways to measure organicmaterial. When analyzing COD, harmful substances such as mercury are often used. The Swedish Environmental Agency has for several years forecasted that this analysis might be banned, and therefore analysis of TOC has become more and more common in Sweden. However, COD is often used as a design parameter when designing new wastewater treatment plants and the European Union’s reference values are given as COD. Hence, both parameters will continue to be used and both need to be taken into consideration. With the aim to improve the knowledge of the relationship between COD and TOC, data series with TOC and COD were collected. The data originated from several different Swedish pulp and paper mills, as well as from different types of waste water streams within each mill. The data series were analyzed using linear regression and correlation analysis, and then compared with the companies’ mean value of the ratio between COD and TOC (the conversion factor). Information about the shift from COD to TOC, and the analyzing methods and pretreatment methods was gathered by conducting interviews with employees at the different mills. The final part of the project was a laboratory study, with the main focus to examine if the conversion factor changed over time. The results showed that the correlation between COD and TOC often was high, but that the conversion factor depended on type of manufacturing process and waste water treatment. Mills with a low use of chemicals had a more similar conversion factor than mills with a more chemical demanding process. Furthermore, a high degree of purification resulted in a lower conversion factor. The conversion factor did not seem to depend on neither the content of suspended solids nor the time of the year. Additionally, the conversion factor was relatively constant over time.
343

Development of linear capacitance-resistance models for characterizing waterflooded reservoirs

Kim, Jong Suk 13 February 2012 (has links)
The capacitance-resistance model (CRM) has been continuously improved and tested on both synthetic and real fields. For a large waterflood, with hundreds of injectors and producers present in a reservoir, tens of thousands of model parameters (gains, time constants, and productivity indices) in a field must be determined to completely define the CRM. In this case obtaining a unique solution in history-matching large reservoirs by nonlinear regression is difficult. Moreover, this approach is more likely to produce parameters that are statistically insignificant. The nonlinear nature of the CRM also makes it difficult to quantify the uncertainty in model parameters. The analytical solutions of the two linear reservoir models, the linearly transformed CRM whose control volume is the drainage volume around each producer (ltCRMP) and integrated capacitance-resistance model (ICRM), are developed in this work. Both models are derived from the governing differential equation of the producer-based representation of CRM (CRMP) that represents an in-situ material balance over the effective pore volume of a producer. The proposed methods use a constrained linear multivariate regression (LMR) to provide information about preferential permeability trends and fractures in a reservoir. The two models’ capabilities are validated with simulated data in several synthetic case studies. The ltCRMP and ICRM have the following advantages over the nonlinear waterflood model (CRMP): (1) convex objective functions, (2) elimination of the use of solver when constraints are ignored, and (3) faster computation time in optimization. In both methods, a unique solution can always be obtained regardless of the number of parameters as long as the number of data points is greater than the number of unknowns (parameters). The methods of establishing the confidence limits on CRMP gains and ICRM parameters are demonstrated in this work. This research also presents a method that uses the ICRM to estimate the gains between newly introduced injectors and existing producers for a homogeneous reservoir without having to do additional simulations or regression on newly simulated data. This procedure can guide geoscientists to decide where to drill new injectors to increase future oil recovery and provide rapid solutions without having to run reservoir simulations for each scenario. / text
344

Exploring the Boundaries of Gene Regulatory Network Inference

Tjärnberg, Andreas January 2015 (has links)
To understand how the components of a complex system like the biological cell interact and regulate each other, we need to collect data for how the components respond to system perturbations. Such data can then be used to solve the inverse problem of inferring a network that describes how the pieces influence each other. The work in this thesis deals with modelling the cell regulatory system, often represented as a network, with tools and concepts derived from systems biology. The first investigation focuses on network sparsity and algorithmic biases introduced by penalised network inference procedures. Many contemporary network inference methods rely on a sparsity parameter such as the L1 penalty term used in the LASSO. However, a poor choice of the sparsity parameter can give highly incorrect network estimates. In order to avoid such poor choices, we devised a method to optimise the sparsity parameter, which maximises the accuracy of the inferred network. We showed that it is effective on in silico data sets with a reasonable level of informativeness and demonstrated that accurate prediction of network sparsity is key to elucidate the correct network parameters. The second investigation focuses on how knowledge from association networks can be transferred to regulatory network inference procedures. It is common that the quality of expression data is inadequate for reliable gene regulatory network inference. Therefore, we constructed an algorithm to incorporate prior knowledge and demonstrated that it increases the accuracy of network inference when the quality of the data is low. The third investigation aimed to understand the influence of system and data properties on network inference accuracy. L1 regularisation methods commonly produce poor network estimates when the data used for inference is ill-conditioned, even when the signal to noise ratio is so high that all links in the network can be proven to exist for the given significance. In this study we elucidated some general principles for under what conditions we expect strongly degraded accuracy. Moreover, it allowed us to estimate expected accuracy from conditions of simulated data, which was used to predict the performance of inference algorithms on biological data. Finally, we built a software package GeneSPIDER for solving problems encountered during previous investigations. The software package supports highly controllable network and data generation as well as data analysis and exploration in the context of network inference. / <p>At the time of the doctoral defense, the following paper was unpublished and had a status as follows: Paper 4: Manuscript.</p><p> </p>
345

The Role of Gender Equality and Economic Development in Explaining Female Smoking Rates

Shariff, Samina 27 April 2007 (has links)
Globally female smoking rates are considerably lower than male smoking rates. However, there is great concern regarding female smoking due to the potential for future increases and the associated harm to health. To gain a better understanding regarding female smoking, this study examines the role of gender equality and economic development in explaining the variability in female smoking rates and female-to-male smoking differentials by examining data from 193 World Health Organization member states. Data on the dependent variables, female smoking prevalence rates and female-to-male smoking prevalence ratio, were obtained from the Tobacco Atlas. Data on independent variables i.e., measures of gender equality and gross national income per capita, proxy measure for economic development, were obtained from the 2005 Human Development Report, Central Intelligence Agency, and the World Bank. A composite gender equality index was constructed from the individual measures of gender equality. Multiple regression analysis showed composite gender equality index and gross national income per capita to be significant positive predictors of relative and absolute female smoking rates, with income being a stronger predicator. Individual measures of gender equality failed to show significance with either dependent variable. The results attest to the need for disentangling smoking from the notion of advancement in gender equality and economic development.
346

Colour development in Pinus radiata D. Don. under kiln-drying conditions.

Dieste, Andrés January 2002 (has links)
This study quantifies discolouration on the surface of Pinus radiata boards during kiln drying, particularly kiln brown stain (KBS), and models it as a function of chemical compounds present in the wood closest to the surface. The discolouration was investigated with two experimental factors: drying time, which consisted in drying at 70/120 ℃ for 0, 8, 16 and 24 hours; and leaching, done at three levels, noleaching, mild and severe, to reduce the soluble compounds present in wood suspected of developing coloured compounds. The colour change was quantified using a reflectance photometer (colour system CIE Yxy, brightness) and by the analysis of digital photographs (colour system CIE Lab). The chemical analysis of the wood closest to the surface of the boards determined fructose, glucose, sucrose (HPLC), total sugar (sum of fructose, glucose and sucrose), total nitrogen (combustion gas analysis), and phenols discriminated by molecular weight (Folin-Ciocalteu method). In the cause-effect analysis, colour was the dependent variable, and drying time and the determinations of chemical compounds were independent variables. After statistical analysis (ANOVA and MANOVA) the dependent variables to be included in the models were luminance factor (Y), brightness (R457 and the blue-to-yellow scale of CIE Lab (b); and the independent variables were drying time, nitrogen, total sugar, and high-molecular-weight phenols. Linear (multivariate regression) and non-linear models (Neural Networks) showed that discolouration during kiln drying was best predicted when the luminance factor (Y) was used to quantify colour change as a function of the content of nitrogen-containing compounds and drying time. Furthermore, the data were fitted into an empirical model based on simple reaction kinetics that considered the rate of discolouration as a function of nitrogen concentration. The results suggest that nitrogen could act as a limiting reactant in Maillard-type reactions that produce colour during kiln drying.
347

Some methods for reducing the total consumption and production prediction errors of electricity: Adaptive Linear Regression of Original Predictions and Modeling of Prediction Errors

Oleksandra, Shovkun January 2014 (has links)
Balance between energy consumption and production of electricityis a very important for the electric power system operation and planning. Itprovides a good principle of effective operation, reduces the generation costin a power system and saves money. Two novel approaches to reduce thetotal errors between forecast and real electricity consumption wereproposed. An Adaptive Linear Regression of Original Predictions (ALROP)was constructed to modify the existing predictions by using simple linearregression with estimation by the Ordinary Least Square (OLS) method.The Weighted Least Square (WLS) method was also used as an alternativeto OLS. The Modeling of Prediction Errors (MPE) was constructed in orderto predict errors for the existing predictions by using the Autoregression(AR) and the Autoregressive-Moving-Average (ARMA) models. For thefirst approach it is observed that the last reported value is of mainimportance. An attempt was made to improve the performance and to getbetter parameter estimates. The separation of concerns and the combinationof concerns were suggested in order to extend the constructed approachesand raise the efficacy of them. Both methods were tested on data for thefourth region of Sweden (“elområde 4”) provided by Bixia. The obtainedresults indicate that all suggested approaches reduce the total percentageerrors of prediction consumption approximately by one half. Resultsindicate that use of the ARMA model slightly better reduces the total errorsthan the other suggested approaches. The most effective way to reduce thetotal consumption prediction errors seems to be obtained by reducing thetotal errors for each subregion.
348

Informação polarimétrica PALSAR/ALOS aplicada à discriminação de espécies e estimação de parâmetros morfológicos de macrófitas

Sartori, Lauriana Rúbio [UNESP] 20 April 2011 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:30:31Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-04-20Bitstream added on 2014-06-13T20:21:13Z : No. of bitstreams: 1 sartori_lr_dr_prud.pdf: 4148637 bytes, checksum: 5616600e595cbbe65fef21b03cd5309c (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O propósito deste trabalho foi avaliar o potencial dos dados PALSAR polarimétricos para discriminar e mapear espécies de macrófitas (vegetação aquática) de uma área alagável da Amazônia, a planície de inundação do Lago Grande de Monte Alegre, no estado do Pará. A coleta de dados foi realizada quase simultaneamente à aquisição dos dados de radar. Três principais espécies de macrófitas foram encontradas na área: Paspalum repens (PR), Hymenachne amplexicaulis (HA) e Paspalum elephantipes (PE). Variáveis morfológicas foram medidas em campo e usadas para derivar outras variáveis tais como a biomassa. Atributos foram gerados a partir da matriz de covariância [C] extraída da imagem ALOS/PALSAR em modo SLC (single look complex). Os atributos polarimétricos foram analisados para as três espécies e identificados aqueles capazes de discriminar as espécies. Foram aplicadas as seguintes abordagens de classificação: baseada em regras, baseada em modelos de decomposição (Decomposições de Freeman-Durden e Cloude-Pottier), baseada em estatística (Classificação supervisionada baseada na distância Wishart) e híbrida (Classificador Wishart com classes de entrada baseadas na decomposição de Cloude-Pottier). Finalmente, a variável morfológica “volume da haste” foi modelada por regressão múltipla em função de alguns atributos polarimétricos. Os resultados sugerem que a imagem polarimétrica banda L possui potencial para discriminar as espécies de macrófitas, sendo os principais atributos para isso sigma zero HH ( ), sigma zero HV ( ) e sigma zero VV ( ), índice de estrutura da copa... / The purpose of this work was to evaluate the potential of fully polarimetric PALSAR data to discriminate and map macrophyte species in the Amazon floodplain, more specifically in the Monte Alegre Lake, in the state of Pará, Brazil. Fieldwork was carried out almost simultaneously to the radar acquisition. Three main species were found in the study area: Paspalum repens (PR), Hymenachne amplexicaulis (HA) and Paspalum elephantipes (PE). Macrophyte morphological variables were measured on the field and used to derive others variables, like the biomass. Attributes were calculated from the covariance matrix [C] derived from the SLC (single look complex) data. The polarimetric attributes were analyzed for the three species and it was identified that ones capable of discriminating them. The following classification approaches were applied: a rule-based classification, model-based classifications (Freeman-Durden and Cloude-Pottier), a statistical-based classification (supervised classification using Wishart distance measure) and a hybrid classification (Wishart classifier with the input classes based on the H/a plane). Finally, the morphological variable “stem volume” was modeled using multiple regression. The findings suggest that the fully polarimetric image has potential for discriminating plant species, being the main attributes sigma-nought HH ( ), sigma-nought HV ( ) and sigma-nought VV ( ), canopy structure index ( ), HH-VV polarimetric coherence ( ), helicity of the third scattering mechanism (τ ), orientation angle of the first scattering mechanism ( ) and scattering type phase of the first mechanism ( ); among the different classifications, only the supervised (Wishart) and the rule-based discriminated the species, with overall accuracy of 75,04% and 87,18%, respectively; the stem volume was modeled using the following attributes: biomass index ( ), volumetric scattering ... (Complete abstract click electronic access below)
349

Imputação de médias para análise de estabilidade e adaptabilidade em experimentos conjuntos incompletos: uma aplicação em café conilon / Imputation of data for the stability and adaptability study in incomplete experiments sets: an application to data of conilon coffee

Oliveira, Rafael Lédo Rocha de 15 February 2012 (has links)
Made available in DSpace on 2015-03-26T13:32:13Z (GMT). No. of bitstreams: 1 texto completo.pdf: 496246 bytes, checksum: 8cb1dcd5339bc6d6dd6f03c0370368bf (MD5) Previous issue date: 2012-02-15 / This study aimed to develop, evaluate and verify the influence of medium values imputation through six methods on the genotype recommendation imputing missing in medium genotype from methodologies of stability and adaptability in experiments incomplete sets of conilon coffee, so that it can determine whether it is appropriate or not the implementation of missing means imputation. The first method imputes a missing value through a mathematical model that is a function of the experimental medium value added the effect of genotype; the second method adds to this model the environmental effect. The third, fourth and fifth methods created impute a missing value through a simple linear regression, whose independent variables are the environmental effects, which are estimated using all available data in the experiment set (method 3), or just the means of the genotypes that were evaluated in all environments (method 4). The independent variable of the fifth method are the mean responses of the genotype most correlated with the one you want to estimate a missing value. The dependent variable of these regressions are the mean responses of the genotype that you want to estimate the missing value. The sixth method keeps the sum of squares of the genotype x environment interaction. In order to evaluate and verify the influence of imputation methods proposed, it was obtained a data set provided by INCAPER (Capixaba Institute of Research, Technical Assistance and Rural Extension). It was from an experiment tin which 38 complete set genotypes (clones) of conilon coffee were evaluated in18 environments according to your productivity (bags/hectare). This experiment was submitted to Lin & Binns (1998) and Eberhart-Russell (1966) stability and adaptability analyses, generating, then, reference recommendations. After that, some means were removed randomly simulating experiments with 1%, 5% and 10% of missing means. Then, new mean values were generated through the imputation methods developed. The evaluation of these methodologies and verification of the influence of imputation on the recommendation of the genotypes was performed by calculating the mean squared error, the Spearman correlation between the Lin & Binns recommendation before and after imputation, and the percentage of changes on the recommendation of the genotypes in relation to the reference Eberhart-Russel recommendation. According to the results obtained in this study, the performance of the imputation of means by the developed methodologies with better performance (2, 3, 4 and 6) in incomplete experiment sets is advisable, since the changes in the recommendations of the genotypes was small compared with the number of missing means in the evaluated experiments. / Este estudo teve por objetivo desenvolver, avaliar e verificar a influência de seis métodos de imputação de médias faltantes na recomendação de genótipos proveniente de metodologias de estabilidade e adaptabilidade em experimentos conjuntos incompletos de café conilon, de modo que seja possível constatar se é conveniente ou não a realização da imputação das médias faltantes. O primeiro método imputa uma média faltante por meio de um modelo que é função da média geral acrescida do efeito do genótipo; já o segundo, adiciona a esse modelo o efeito de ambiente. O terceiro, quarto e quinto métodos elaborados imputam uma média faltante por meio de uma regressão linear simples, cujas variáveis independentes são os índices ambientais, que são estimados utilizando todos os dados disponíveis no experimento conjunto (método 3), ou apenas as médias dos genótipos que foram avaliados em todos os ambientes (método 4). A variável independente do quinto método são as respostas médias do genótipo de maior correlação com aquele que se deseja estimar um valor faltante. A variável dependente destas regressões são as respostas médias do genótipo que se deseja estimar o valor faltante. O sexto método mantém a soma de quadrados da interação genótipo x ambiente. Para que a avaliação e verificação da influência dos métodos de imputação propostos fossem possíveis, foi obtido um conjunto de dados cedido pela INCAPER (Instituto Capixaba de Pesquisa, Assistência Técnica e Extensão Rural) oriundo de um experimento conjunto completo em que 38 genótipos (clones) de café conilon foram avaliados em 18 ambientes segundo suas produtividades (sacas/hectare). Este experimento foi submetido às análises de estabilidade e adaptabilidade de Lin & Binns (1998) e Eberhart-Russel (1966), gerando, dessa forma, recomendações padrão. Feito isto, médias foram retiradas aleatoriamente simulando experimentos com 1%, 5% e 10% de médias faltantes. Daí, por meio dos métodos de imputação elaborados, novos valores de médias foram gerados. A avaliação dessas metodologias e a verificação da influência da imputação na recomendação dos genótipos foram realizadas por meio do cálculo do Erro Quadrático Médio, da Correlação de Spearman entre a recomendação de Lin & Binns antes e após a imputação das médias, e da porcentagem de mudanças na recomendação dos genótipos em relação à recomendação padrão de Eberhart-Russel. Conforme os resultados obtidos neste estudo, a realização da imputação das médias mediante as metodologias desenvolvidas com melhor desempenho (2, 3, 4 e 6) em experimentos conjuntos incompletos é aconselhável, uma vez que a alteração nas recomendações dos genótipos avaliados foi pequena se comparado com o número de médias faltantes nos ensaios avaliados.
350

Informação polarimétrica PALSAR/ALOS aplicada à discriminação de espécies e estimação de parâmetros morfológicos de macrófitas /

Sartori, Lauriana Rúbio. January 2011 (has links)
Resumo: O propósito deste trabalho foi avaliar o potencial dos dados PALSAR polarimétricos para discriminar e mapear espécies de macrófitas (vegetação aquática) de uma área alagável da Amazônia, a planície de inundação do Lago Grande de Monte Alegre, no estado do Pará. A coleta de dados foi realizada quase simultaneamente à aquisição dos dados de radar. Três principais espécies de macrófitas foram encontradas na área: Paspalum repens (PR), Hymenachne amplexicaulis (HA) e Paspalum elephantipes (PE). Variáveis morfológicas foram medidas em campo e usadas para derivar outras variáveis tais como a biomassa. Atributos foram gerados a partir da matriz de covariância [C] extraída da imagem ALOS/PALSAR em modo SLC (single look complex). Os atributos polarimétricos foram analisados para as três espécies e identificados aqueles capazes de discriminar as espécies. Foram aplicadas as seguintes abordagens de classificação: baseada em regras, baseada em modelos de decomposição (Decomposições de Freeman-Durden e Cloude-Pottier), baseada em estatística (Classificação supervisionada baseada na distância Wishart) e híbrida (Classificador Wishart com classes de entrada baseadas na decomposição de Cloude-Pottier). Finalmente, a variável morfológica "volume da haste" foi modelada por regressão múltipla em função de alguns atributos polarimétricos. Os resultados sugerem que a imagem polarimétrica banda L possui potencial para discriminar as espécies de macrófitas, sendo os principais atributos para isso sigma zero HH ( ), sigma zero HV ( ) e sigma zero VV ( ), índice de estrutura da copa ... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The purpose of this work was to evaluate the potential of fully polarimetric PALSAR data to discriminate and map macrophyte species in the Amazon floodplain, more specifically in the Monte Alegre Lake, in the state of Pará, Brazil. Fieldwork was carried out almost simultaneously to the radar acquisition. Three main species were found in the study area: Paspalum repens (PR), Hymenachne amplexicaulis (HA) and Paspalum elephantipes (PE). Macrophyte morphological variables were measured on the field and used to derive others variables, like the biomass. Attributes were calculated from the covariance matrix [C] derived from the SLC (single look complex) data. The polarimetric attributes were analyzed for the three species and it was identified that ones capable of discriminating them. The following classification approaches were applied: a rule-based classification, model-based classifications (Freeman-Durden and Cloude-Pottier), a statistical-based classification (supervised classification using Wishart distance measure) and a hybrid classification (Wishart classifier with the input classes based on the H/a plane). Finally, the morphological variable "stem volume" was modeled using multiple regression. The findings suggest that the fully polarimetric image has potential for discriminating plant species, being the main attributes sigma-nought HH ( ), sigma-nought HV ( ) and sigma-nought VV ( ), canopy structure index ( ), HH-VV polarimetric coherence ( ), helicity of the third scattering mechanism (τ ), orientation angle of the first scattering mechanism ( ) and scattering type phase of the first mechanism ( ); among the different classifications, only the supervised (Wishart) and the rule-based discriminated the species, with overall accuracy of 75,04% and 87,18%, respectively; the stem volume was modeled using the following attributes: biomass index ( ), volumetric scattering ... (Complete abstract click electronic access below) / Orientador: Nilton Nobuhiro Imai / Coorientador: José Cláudio Mura / Banca: Evlyn Marcia Leão de Moraes Novo / Banca: Thiago Sanna Freire Silva / Banca: João Roberto dos Santos / Banca: Vilma Mayumi Tachibana / Doutor

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