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Orientador: Rouverson Pereira da Silva / Coorientador: Anderson de Toledo / Banca: Carlos Eduardo Angeli Furlani / Banca: Welington Gonzaga do Vale / Resumo: Na cadeia produtiva do setor sucroenergético, o processo de colheita mecanizada de cana-de-açúcar é considerado um dos maiores gargalos econômicos, apresentando baixa eficiência operacional e elevadas perdas. Em busca de minimizar estes problemas e auxiliar a melhoria nos processos, este trabalho objetivou avaliar o potencial de uma ferramenta estatística para a gestão dos dados de velocidade e perdas na colheita mecanizada de cana-de-açúcar, levantados durante duas safras, para cinco Frentes de trabalho. Os dados foram coletados em uma Usina da região de Ribeirão Preto, durante 9 meses da safra 2012/2013 e 9 meses da safra 2013/2014. As perdas foram subdivididas em: toco, rebolo estilhaçado, pedaço solto e fixo, cana inteira, estilhaço e total, para cada Frente separadamente. Os dados foram agrupados em 40 períodos de colheita, sendo então realizadas análises estatísticas utilizando o software Minitab 16®. Os valores de perdas geraram curvas com características assimétricas positivas e leptocúrticas. Todos os coeficientes de variação foram elevados demonstrando a grande variabilidade dos índices de perdas. Os valores de perdas na colheita mantiveram-se instáveis em todas as frentes, porém, os resultados foram considerados dentro dos índices de perdas aceitáveis para as usinas brasileiras / Abstract: In the sugarcane production chain, the sugarcane process for mechanized harvesting is considered one of the greatest economic bottlenecks, showing low levels of operational efficiencies and high levels of losses. To assist the improvement in harvesting processes and procedures you can adopt quality controls improving harvesting operations and by reducing the levels of losses. The objective of this work was to evaluate the losses at harvest data collected during two harvest season analyzing five teams. The losses data were collected in 9 months of the 2012/2013 and 9 months of the 2013/2014 harvest season by the harvest quality team. The losses were subdivided into: stubbles, stalks, splinted stalks, untied and fixed piece, whole cane, cane top, splint and total each team separately. The loss data were subdivided weekly, totaling 40 weeks of harvest, and the statistical analyses were using Minitab 16® software. The values of losses generated curves with asymmetrical features positive leptokurtic. Almost all coefficients of variation were high showing a large variability among the data collected and harvest losses indexes. With regard to the values of harvest losses, all indexes remained out of control for all teams, however the results were considered within acceptable loss rates for Brazilian Sugarcane mills / Mestre

Orientador: Rouverson Pereira da Silva / Coorientador: David Luciano Rosalen / Coorientador: Ángel Lázaro Sánchez Isnaga / Banca: Fabio Alexandre Cavichioli / Banca: Leonardo Campos de Assis / Resumo: Dentro do contexto de Agricultura de Precisão, a utilização do direcionamento automático é sem dúvidas uma das ferramentas mais populares entre os agricultores, no entanto, são poucos os produtores de amendoim que utilizam dessa tecnologia. Os benefícios do piloto automático podem ser ainda maiores na cultura de amendoim, visto que uma das principais queixas dos operadores é a dificuldade em manter o trator alinhado com a fileira da cultura no momento do arranquio, o que poderia ser reduzido quando se realiza a semeadura e o arranquio com a utilização do Piloto Automático. Nesse sentido foram realizados dois estudos, sendo o primeiro para avaliar o erro de paralelismo na operação de arranquio, mediante projeto para a execução, com direcionamento automático com sinal RTX. No segundo buscou-se identificar os principais problemas que afetam a operação de arranquio, bem como o erro de paralelismo. No primeiro foi possível observar que o uso do sinal proporcionou erros inferiores a 3,8 cm, da linha projetada com a linha executada na semeadura. No segundo, relata-se que para que o arranquio seja feito com menores perdas deve-se manter monitoramento constante de parâmetros como maturação e teor de água do solo e profundidade de trabalho do arrancador-invertedor. Por fim, é possível concluir que o uso do piloto automático reduz os erros de paralelismo, tanto na semeadura quanto no arranquio de amendoim. / Abstract: Among the precision farming tools, the use of automatic steering is without doubt one of the most popular among farmers, however, few farmers peanut using this technology. The benefits of autopilot may be even greater in the peanut crop, and one of the main complaints of the operators is the difficulty in maintaining the tractor lined up with the culture of the row at the digging. Thus, these effects can be reduced when performing the sowing and digging using the Autopilot. That it was conducted two studies, the first to evaluate the parallelism in the digging operation by design to the implementation, with automatic routing with RTX signal. The second sought to identify the main problems affecting the digging operation as well as the parallelism. At first it was possible to observe that the use of the sign provided lower errors to 3.8 cm, the line designed with the line running at sowing. In the second, it is reported that for the digging is done with smaller losses should be constant monitoring of parameters such as maturation and soil water content and depth of work Starter-Flipping. Finally, we conclude that the use of the autopilot reduces the parallelism errors, both in seeding and in peanut digging. / Mestre

Made available in DSpace on 2015-01-26T13:21:13Z (GMT). No. of bitstreams: 0 Previous issue date: 2014-07-10Bitstream added on 2015-01-26T13:30:59Z : No. of bitstreams: 1 000801679_20150801.pdf: 18193 bytes, checksum: de8bcc8deb25bf818c0af6df916adcc8 (MD5) Bitstreams deleted on 2015-08-03T12:20:54Z: 000801679_20150801.pdf,. Added 1 bitstream(s) on 2015-08-03T12:22:16Z : No. of bitstreams: 1 000801679.pdf: 1374936 bytes, checksum: 3161bdd1d262d5a72ae2e21bb7d33b48 (MD5) / Na cadeia produtiva do setor sucroenergético, o processo de colheita mecanizada de cana-de-açúcar é considerado um dos maiores gargalos econômicos, apresentando baixa eficiência operacional e elevadas perdas. Em busca de minimizar estes problemas e auxiliar a melhoria nos processos, este trabalho objetivou avaliar o potencial de uma ferramenta estatística para a gestão dos dados de velocidade e perdas na colheita mecanizada de cana-de-açúcar, levantados durante duas safras, para cinco Frentes de trabalho. Os dados foram coletados em uma Usina da região de Ribeirão Preto, durante 9 meses da safra 2012/2013 e 9 meses da safra 2013/2014. As perdas foram subdivididas em: toco, rebolo estilhaçado, pedaço solto e fixo, cana inteira, estilhaço e total, para cada Frente separadamente. Os dados foram agrupados em 40 períodos de colheita, sendo então realizadas análises estatísticas utilizando o software Minitab 16®. Os valores de perdas geraram curvas com características assimétricas positivas e leptocúrticas. Todos os coeficientes de variação foram elevados demonstrando a grande variabilidade dos índices de perdas. Os valores de perdas na colheita mantiveram-se instáveis em todas as frentes, porém, os resultados foram considerados dentro dos índices de perdas aceitáveis para as usinas brasileiras / In the sugarcane production chain, the sugarcane process for mechanized harvesting is considered one of the greatest economic bottlenecks, showing low levels of operational efficiencies and high levels of losses. To assist the improvement in harvesting processes and procedures you can adopt quality controls improving harvesting operations and by reducing the levels of losses. The objective of this work was to evaluate the losses at harvest data collected during two harvest season analyzing five teams. The losses data were collected in 9 months of the 2012/2013 and 9 months of the 2013/2014 harvest season by the harvest quality team. The losses were subdivided into: stubbles, stalks, splinted stalks, untied and fixed piece, whole cane, cane top, splint and total each team separately. The loss data were subdivided weekly, totaling 40 weeks of harvest, and the statistical analyses were using Minitab 16® software. The values of losses generated curves with asymmetrical features positive leptokurtic. Almost all coefficients of variation were high showing a large variability among the data collected and harvest losses indexes. With regard to the values of harvest losses, all indexes remained out of control for all teams, however the results were considered within acceptable loss rates for Brazilian Sugarcane mills

Orientador: Carlos Eduardo Angeli Furlani / Coorientador: Rouverson Pereira da Silva / Banca: Carlos Alessandro Chioderoli / Banca: Paulo Roberto Arbex Silva / Resumo: O Brasil é o maior produtor mundial de cana-de-açúcar, devido a expansão de áreas cultivadas, a adubação mecanizada torna-se muito importante para o aumento do desempenho operacional nesta cultura, porém esta adubação pode demonstrar alguns problemas na distribuição de fertilizantes, como a não realização da caracterização dos fertilizantes por meio do ângulo de repouso, granulometria e densidade dos nutrientes, entre outros. Dessa forma, torna-se necessário o desenvolvimento de novas tecnologias que possibilitem uma melhora na aplicação de fertilizantes na cultura da cana-de-açúcar. À vista disso, um novo conceito de adubadora está em desenvolvimento considerada como protótipo, pois esta realiza aplicação individualizada de nitrogênio, fósforo e potássio proporcionando maior eficiência na distribuição destes em relação às outras adubadoras. Com este trabalho o objetivo foi avaliar aplicação mecanizada de N-P-K individualizada na cultura da cana-de-açúcar. O experimento foi desenvolvido no município de Matão em área de cana-de-açúcar pertencente à Fazenda Cascavel, possuindo 1,66 ha aproximadamente de área experimental. O delineamento experimental foi Inteiramente Casualizado (DIC), com três tratamentos e trinta repetições por tratamento. Este delineamento foi estabelecido conforme os critérios do controle de qualidade, sendo o monitoramento das variáveis realizado durante a operação de adubação. Ao final do período de avaliação foram coletados 90 pontos amostrais no total, sendo 30 pontos por tratamento. Os tratamentos foram: 1- Adubação mecanizada, sem aplicação de herbicida; 2- Operação conjugada (aplicação simultânea de herbicida e adubação); e 3- Duas operações (aplicação separada de herbicida e adubo). Concluiu-se que a melhor qualidade operacional por meio das cartas de controle foi o tratamento 3, sendo duas operações (aplicação separada de herbicida e adubo)... / Abstract: The Brazil is the largest producer of sugarcane, due to expansion of cultivated areas, mechanized fertilizer becomes very important for the increase in operating performance in this culture, but this fertilization may show some problems in the distribution of fertilizers, so that when not performing the characterization of fertilizers through the angle of repose, particle size and density of nutrients, among other. Thus, it becomes necessary to develop new technologies that enable an improvement in the application of fertilizers in the cultivation of sugarcane. In view of this, a new concept of fertilizer in development considered as a prototype because this performs individualized application of nitrogen, phosphorus and potassium, providing greater efficiency in the distribution of these over other fertilizer machine. With this work the objective was to evaluate the mechanical application of NPK individualized culture of sugarcane. The experiment was conducted in the Matão municipality in the area of sugarcane belonging to the Fazenda Cascavel, possessing approximately 1.66 ha experimental area. The experimental design was completely randomized (DIC), with three treatments and thirty replications for treatment. This design was established according to the criteria of quality control, and monitoring of variables held during fertilization operation. At the end of the evaluation period were collected 90 sample points in total, with 30 points per treatment. The treatments were: 1- mechanized fertilized, without herbicide; 2- Operation combined (simultaneous application of herbicide and fertilizer); and 3- Two operations (separate application of herbicide and fertilizer). It was concluded that the best operational quality through control charts was the third treatment, two operations (separate application of herbicide and fertilizer) for presenting less variability. The right side of fertilizer machine was the best for having applied ... / Mestre

This study uses simulation to examine differences between fixed sampling interval (FSI) and variable sampling interval (VSI) Shewhart X-bar control charts for processes that produce positively autocorrelated data. The influence of sample size (1 and 5), autocorrelation parameter, shift in process mean, and length of time between samples is investigated by comparing average time (ATS) and average number of samples (ANSS) to produce an out of control signal for FSI and VSI Shewhart X-bar charts. These comparisons are conducted in two ways: control chart limits pre-set at ±3σ_x / √n and limits computed from the sampling process. Proper interpretation of the Shewhart X-bar chart requires the assumption that observations are statistically independent; however, process data are often autocorrelated over time. Results of this study indicate that increasing the time between samples decreases the effect of positive autocorrelation between samples. Thus, with sufficient time between samples the assumption of independence is essentially not violated. Samples of size 5 produce a faster signal than samples of size 1 with both the FSI and VSI Shewhart X-bar chart when positive autocorrelation is present. However, samples of size 5 require the same time when the data are independent, indicating that this effect is a result of autocorrelation. This research determined that the VSI Shewhart X-bar chart signals increasingly faster than the corresponding FSI chart as the shift in the process mean increases. If the process is likely to exhibit a large shift in the mean, then the VSI technique is recommended. But the faster signaling time of the VSI chart is undesirable when the process is operating on target. However, if the control limits are estimated from process samples, results show that when the process is in control the ARL for the FSI and the ANSS for the VSI are approximately the same, and exceed the expected value when the limits are fixed.

Change-point detection in hazard rate function is an important research topic in survival analysis. In this dissertation, we firstly review existing methods for single change-point detection in piecewise exponential hazard model. Then we consider the problem of estimating the change point in the presence of right censoring and long-term survivors while using Kaplan-Meier estimator for the susceptible proportion. The maximum likelihood estimators are shown to be consistent. Taking one step further, we propose an counting process based and least squares based change-point detection algorithm. For single change-point case, consistency results are obtained. We then consider the detection of multiple change-points in the presence of long-term survivors via maximum likelihood based and counting process based method. Last but not least, we use a weighted least squares based and counting process based method for detection of multiple change-points with long-term survivors and covariates. For multiple change-points detection, simulation studies show good performances of our estimators under various parameters settings for both methods. All methods are applied to real data analyses. / Includes bibliography. / Dissertation (Ph.D.)--Florida Atlantic University, 2014. / FAU Electronic Theses and Dissertations Collection

We consider a principal components based decomposition of the expected value of the multivariate quadratic loss function, i.e., MQL. The principal components are formed by scaling the original data by the contents of the loss constant matrix, which defines the economic penalty associated with specific variables being off their desired target values. We demonstrate the extent to which a subset of these ``loss-scaled principal components", i.e., LSPC, accounts for the two components of expected MQL, namely the trace-covariance term and the off-target vector product. We employ the LSPC to solve a robust design problem of full and reduced dimensionality with deterministic models that approximate the true solution and demonstrate comparable results in less computational time. We also employ the LSPC to construct a test statistic called loss-scaled T^2 for multivariate statistical process control. We show for one case how the proposed test statistic has faster detection than Hotelling's T^2 of shifts in location for variables with high weighting in the MQL. In addition we introduce a principal component based decomposition of Hotelling's T^2 to diagnose the variables responsible for driving the location and/or dispersion of a subgroup of multivariate observations out of statistical control. We demonstrate the accuracy of this diagnostic technique on a data set from the literature and show its potential for diagnosing the loss-scaled T^2 statistic as well.

This study develops a heuristic procedure for specifying parameters for a neural network configuration (learning rate, momentum, and the number of neurons in a single hidden layer) in Shewhart X-bar control chart applications. Also, this study examines the replicability of the neural network solution when the neural network is retrained several times with different initial weights.

Orientadores: Mario Jino / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Eletrica e de Computação / Made available in DSpace on 2018-08-04T03:55:01Z (GMT). No. of bitstreams: 1 Batista_GabrieladeFatima_M.pdf: 1354598 bytes, checksum: 95bb9bb4e444a6f9b717df69650f4e8b (MD5) Previous issue date: 2005 / Resumo: Organizações de alto nível de maturidade têm como meta principal a melhoria contínua de seus processos. Essas organizações usam sistematicamente métricas e fazem análise dos dados coletados para tomada de decisão, ou seja, fazem efetivamente gerenciamento por dados. Avaliação quantitativa da capacidade do processo de software definido para o projeto e suas variações permite planejar e gerenciar melhor os projetos. Considerando a necessidade de medir, prever e ajustar o processo de software para alcançar as metas de qualidade, um programa de medição é proposto com o intuito de dar suporte à gerência quantitativa. O programa de medição apresenta métricas alinhadas às metas organizacionais e exige que, após a coleta dos dados e sua análise, os envolvidos nessas métricas - um gerente administrativo, um gerente funcional, um líder de projeto ou um desenvolvedor - comprometam-se a usar os resultados da análise para identificar os desvios de processo e aplicar as ações corretivas necessárias; desta forma, pode-se controlar o desempenho do processo de desenvolvimento de software dentro dos limites aceitáveis. Para apoiar o processo de implantação e aplicação de métricas, uma ferramenta de coleta, validação e análise dos dados, baseada em controle estatístico de processo, denominada Vigia, foi desenvolvida. Vigia pode ser usada para controlar o desempenho do processo de software definido para o projeto assegurando que o processo não compromete as metas de qualidade da organização nem as metas de negócio, por meio de ações corretivas em tempo real e, conseqüentemente, de ajustes no processo de software. Um estudo de caso foi realizado na Motorola Industrial para avaliar tanto o programa de medição como a ferramenta Vigia / Abstract: Organizations of a high level of maturity have as main goal the continuous improvement of their processes. Such organizations systematically apply metrics by measuring process performance and analyzing these measurements to make decisions; hence, they effectively perform management by data. Quantitative assessment of the performance of the project's defined software process and its variations allows better planning and management of projects. Considering the need for measuring, predicting and adjusting the software process to reach quality goals, a measurement program is being proposed to give support to quantitative management. The measurement program presents metrics aligned to the organizational goals and requires that, after data collection and analysis, the metrics stakeholders - a senior manager, a functional manager, a project leader or a developer - be committed to use the results of the analysis to identify process deviations and to apply the necessary corrective actions. In this way, we may control the performance of the project's defined software process within acceptable limits. To support deployment of the measurement process and application of metrics, a tool to collect, validate and analyze data, based on statistical process control, called Vigia, was developed. Vigia can be used to control the performance of the project's defined software process, assuring that the process does not compromise neither the organizational quality goals nor the business goals through corrective actions in near-real time. Consequently, it carries through adjustments in the software process. A case study was carried out at Motorola Company to evaluate the measurement program as well as the Vigia tool / Mestrado / Engenharia de Computação / Mestre em Engenharia Elétrica