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11	Estimação de parâmetros genéticos de produção de leite e de gordura da raça Pardo-suíça, utilizando metodologias freqüentista e bayesiana / Estimation of genetic parameters of milk and fat yield of Brown-Swiss cows using frequentist and bayesian methodologies Yamaki, Marcos 31 July 2006 (has links) Made available in DSpace on 2015-03-26T13:55:08Z (GMT). No. of bitstreams: 1 texto completo.pdf: 905318 bytes, checksum: 167ccc3c1b47051e3ce28eb0224bed43 (MD5) Previous issue date: 2006-07-31 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / First lactation data of 6.262 Brown-Swiss cows from 311 herds, daughters of 803 sires with calving between 1980 and 2003 were used to estimate genetic parameters for milk and fat production traits. The components of variance were estimated by restricted maximum likelihood (REML) and bayesian methods, using animal model with uni and two-traits analisys . The estimation by REML was obtained with the software MTDFREML (BOLDMAN et al. 1995) testing unitrait models with different effects to covariables and considering contemporary group and season as fixed effect. The best fitting obtained on unitrait analisys were used on two-trait analisys. The estimative of additive variance was reduced when lactation length was included on the model suggesting that the animals were been fitted to the same base on the capacity of transmit a longer or shorter lactation length to the progeny. Therefore, fitting to this covariable is not recommended. On the other side, the age of calving has linearly influenced milk and fat production. The heritability estimates were 0,26 and 0,25 to milk and fat yield respectively with genetic correlation of 0,95. the high correlation among these traits suggests that part of genes that acts on milk yield also respond to fat yield, in such way that selection for milk yield results, indirectly, in increase on fat yield. The estimation by Bayesian inference was made on software MTGSAM (VAN TASSELL E VAN VLECK, 1995). Chain lengths were tested to obtain the marginal posterior densities of unitrait analisys, the best option of chain length, burn-in and sampling interval was used on two-trait analisys. The burn-in periods were tested with the software GIBANAL (VAN KAAM, 1998) witch analysis inform a sampling interval for each burn-in tested, the criteria for choosing the sampling interval was made with the serial correlation resulting by burn-in and sampling process. The heritability estimates were 0,33 ± 0,05 for both traits with genetic correlation of 0,95. Similar results were obtained on studies using the same methodology on first lactation records. The stationary phase adequately reached with a 500.000 chain length and 30.000 burn-in iteractions. / Dados de primeira lactação de 6.262 vacas distribuídas em 311 rebanhos, filhas de 803 touros com partos entre os anos de 1980 e 2003 foram utilizados para estimar de componentes de variância para as características de produção de leite e gordura com informações de primeira lactação, em animais da raça Pardo-Suíça. Os componentes de variância foram estimados pelo método da máxima verossimilhança restrita (REML) e Bayesiano, sob modelo animal, por meio de análises uni e bicaracterística. A estimação realizada via REML foi obtida com o programa MTDFREML (BOLDMAN et al. 1995) testando modelos unicaracterística com diferentes efeitos para as covariáveis e considerados grupo contemporâneo e estação como efeitos fixos. Os melhores ajustes obtidos nas analises unicaracterística foram utilizados na análise bicaracterística. A duração da lactação reduziu a estimativa da variância aditiva quando era utilizada no modelo sugerindo que os animais estariam sendo corrigidos para uma mesma base quanto à capacidade de imprimir duração da lactação mais longa ou mais curta à progênie sendo, portanto, não recomendado o ajuste para esta covariável. Já a idade da vaca ao parto, influenciou linearmente a produção de leite e gordura. As herdabilidades estimadas foram 0,26 e 0,25 para produção de leite e gordura respectivamente com correlação genética de 0,95. A alta correlação entre a produção de leite e gordura obtida sugere que parte dos genes que atuam na produção de leite também responde pela produção de gordura, de tal forma que a seleção para a produção de leite resulta, indiretamente, em aumentos na produção de gordura. A estimação via inferência Bayesiana foi realizada com o programa MTGSAM (VAN TASSELL E VAN VLECK, 1995). Foram testados diversos tamanhos de cadeia para a obtenção das densidades marginais a posteriori das análises unicaracterística, a melhor proposta para o tamanho de cadeia, burn-in e amostragem foi utilizada para a análise bicaracterística. Os períodos de burn-in foram testados pelo programa GIBANAL (VAN KAAM, 1998) cujas análises fornecem um intervalo de amostragem para cada burn-in testado, o critério de escolha do intervalo de amostragem foi feito de acordo com a correlação serial, resultante do burn-in e do processo de amostragem. As estimativas de herdabilidade obtidas foram 0,33 ± 0,05 para ambas as características com correlação de 0,95. Resultados similares foram obtidos em estudos utilizando a mesma metodologia em informações de primeira lactação. A fase estacionária foi adequadamente atingida com uma cadeia de 500.000 iterações e descarte inicial de 30.000 iterações. REML Amostrador de GIBBS Bovino de leite Máxima verossimilhança restrita Teoria bayesiana REML GIBBS sampler Dairy cattle Restricted maximum likelihood Bayesian theory
12	Medium term load forecasting in South Africa using Generalized Additive models with tensor product interactions Ravele, Thakhani 21 September 2018 (has links) MSc (Statistics) / Department of Statistics / Forecasting of electricity peak demand levels is important for decision makers in Eskom. The overall objective of this study was to develop medium term load forecasting models which will help decision makers in Eskom for planning of the operations of the utility company. The frequency table of hourly daily demands was carried out and the results show that most peak loads occur at hours 19:00 and 20:00, over the period 2009 to 2013. The study used generalised additive models with and without tensor product interactions to forecast electricity demand at 19:00 and 20:00 including daily peak electricity demand. Least absolute shrinkage and selection operator (Lasso) and Lasso via hierarchical interactions were used for variable selection to increase the model interpretability by eliminating irrelevant variables that are not associated with the response variable, this way also over tting is reduced. The parameters of the developed models were estimated using restricted maximum likelihood and penalized regression. The best models were selected based on smallest values of the Akaike information criterion (AIC), Bayesian information criterion (BIC) and Generalized cross validation (GCV) along with the highest Adjusted R2. Forecasts from best models with and without tensor product interactions were evaluated using mean absolute percentage error (MAPE), mean absolute error (MAE) and root mean square error (RMSE). Operational forecasting was proposed to forecast the demand at hour 19:00 with unknown predictor variables. Empirical results from this study show that modelling hours individually during the peak period results in more accurate peak forecasts compared to forecasting daily peak electricity demand. The performance of the proposed models for hour 19:00 were compared and the generalized additive model with tensor product interactions was found to be the best tting model. / NRF Generalized additive models Lazeso Lazeso via hierarchical interaction Medium term load forecasting Penalized regression Restricted maximum likelihood Tensor product interactions Time series 333.79320968 Electric power-plants -- Load Electric utilities -- South Africa Electric power -- Rates -- South Africa Electricity -- South Africa
13	Birds, bats and arthropods in tropical agroforestry landscapes: Functional diversity, multitrophic interactions and crop yield Maas, Bea 20 November 2013 (has links) No description available. 630 birds bats arthropods multitrophic interactions agroforestry tropical landscape forest margin landscape functional diversity crop yield exclosure experiments experimental exclusion arthropod suppression avian predation ecosystem services mist netting point counts artificial plasticine caterpillar dummy experiment biological control monitoring mapping Lemon-bellied White-eye Grosbeak Starling Zosterops chloris Scissiostrum dubium Theobroma cacao cacao agroforestry cacao diseases cacao harvest cacao pests flying vertebrates aerial insectivores volant vertebrates logging breeding colony flower herbivory mesopredator release predatory insects ants spiders aphids Lepidoptera Coleoptera Lepidopteran larvae sustainable agriculture sustainable agroforestry management implications management recommendations applied managament extensive land use management landscape management conservation biodiversity-friendly dbh distance to forest forest proximity habitat conversion herbivory Indonesia insectivorous bats insectivorous birds invertebrates Central Sulawesi Napu valley leaf gleaning leaf herbivory pests insects phytophagous insects plant productivity remnant forest trees shade tree managament South-east Asia Paleotropics tropical landscape tree height landscape gradient local shade management Cacao Pod Borer Cherelle Wilt fruit abortion Helopeltis sulawesi deforestation habitat fragmentation land use intensification forest margin species critical decline predation experiment species-specific functions Southeast Asia biodiversity conservation mesopredators food security human welfare human well-being poverty alleviation poverty reduction smallholder cacao smallholder plantation cacao farmers sustainable cacao management landscape perspective landscape scale large scale field experiment long term field experiment human wellbeing economic importance economic value valuation ecosystem services landscape matrix yield quality yield quantity fruit productivity species identity species diversity species richness ecosystem functioning pesticide use chemical compounds complex food web tritrophic interactions wildlife-friendly rural livelihoods endangered bird species endangered bat species endemic endemic birds endemic bats beneficial impact IUCN Lore Lindu National Park bioindicator indicator species forest margin agricultural habitat agroforestry systems population density predation activity species activity cacao flower cacao pod Orthoptera linear mixed effect models Tukey Post Hoc Test AICc model selection generalized least squares restricted maximum likelihood model simplification species richness estimator species accumulation linear mixed-effects models Likelihood Ratio Test Maximum Likelihood nocturnal insects diurnal arthropods nocturnal arthropods diurnal insects landscape context Land- und Forstwirtschaft (PPN621302791)

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