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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.
11

William Tennent and the Log College a common man and an uncommon legacy /

Schnittjer, Gary Edward. January 1992 (has links) (PDF)
Thesis (Th. M.)--Dallas Theological Seminary, 1992. / Includes bibliographical references (leaves 245-267).
12

Random coefficients in linear models

Jones, Richard Henry. January 1900 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1980. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 290-293).
13

[en] AN ARCHITECTURE FOR REAL TIME LOG EVENTS PROCESSING / [pt] UMA ARQUITETURA PARA PROCESSAMENTO DE EVENTOS DE LOG EM TEMPO REAL

RICARDO GOMES CLEMENTE 10 December 2008 (has links)
[pt] Logs são, atualmente, riquíssima fonte de informação para administradores de sistemas e analistas de negócio. Em ambientes com grande volume de acesso e infra-estrutura de centenas de servidores, processar toda a informação gerada e correlacioná-la com o objetivo de identificar situações de interesse técnico e de negócio em tempo real, é considerado um grande desafio. Nesse sentido, são explicados tanto os conceitos relacionados aos arquivos de log e aos sistemas que se propõem a gerenciá-los, quanto os métodos e ferramentas de correlação de eventos em tempo real, para que, então, seja proposta uma arquitetura de sistema capaz de lidar com o desafio citado. Por fim, um protótipo é desenvolvido e uma prova de conceito baseada em um caso real de uso é realizada. / [en] Logs are, nowadays, a rich source of information for system administrators and business analysts. In environments with a high access volume and hundreds of servers, to process every generated information and correlate it, in order to identify interesting technical and business situations in real time, is considered a challenge. Considering that, concepts related to log files and systems that aim to manage it, besides methods and tools for real time event correlation are presented, in order to propose a system architecture capable of overcoming the stated challenge. At last, a prototype is developed and a concept prove based on a real case is done.
14

Novas funções de ativação em redes neurais artificiais multilayer perceptron

GOMES, Gecynalda Soares da Silva 31 January 2010 (has links)
Made available in DSpace on 2014-06-12T15:52:11Z (GMT). No. of bitstreams: 2 arquivo3194_1.pdf: 1782444 bytes, checksum: 1982844f90df3787391d8faa431cde16 (MD5) license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) Previous issue date: 2010 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / Em redes neurais artificiais (RNAs), as funções de ativação mais comumente usadas são a função sigmóide logística e a função tangente hiperbólica, dependendo das características dos dados. Entretanto, a escolha da função de ativação pode influenciar fortemente o desempenho e a complexidade da rede neural. Neste trabalho, com o objetivo de melhorar o desempenho dos modelos de redes neurais, propomos o uso de novas funções de ativação no processamento das unidades da rede neural. Aqui, as funções não-lineares implementadas são as inversas das funções de ligação usadas em modelos de regressão binomial, essas funções são: complemento log-log, probit, log-log e Aranda, sendo que esta última função apresenta um parâmetro livre e é baseada na família de transformações Aranda-Ordaz. Uma avaliação dos resultados do poder de predição com estas novas funções através de simulação Monte Carlo é apresentada. Além disso, foram realizados diversos experimentos com aproximação de funções contínuas e arbitrárias, com regressão e com previsão de séries temporais. Na utilização da função de ativação com parâmetro livre, duas metodologias foram usadas para a escolha do parâmetro livre, l . A primeira foi baseada em um procedimento semelhante ao de busca em linha (line search). A segunda foi usada uma metodologia para a otimização global dessa família de funções de ativação com parâmetro livre e dos pesos das conexões entre as unidades de processamento da rede neural. A ideia central é otimizar simultaneamente os pesos e a função de ativação usada em uma rede multilayer perceptron (MLP), através de uma abordagem que combina as vantagens de simulated annealing, de tabu search e de um algoritmo de aprendizagem local. As redes utilizadas para realizar esses experimentos foram treinadas através dos seguintes algoritmos de aprendizagem: backpropagation (BP), backpropagation com momentum (BPM), backpropagation baseado no gradiente conjugado com atualizações Fletcher-Reeves (CGF) e Levenberg-Marquardt (LM)
15

On low-lying zeros of automorphic L-functions

Guloglu, Ahmet Muhtar 13 July 2005 (has links)
No description available.
16

An Analysis of Log Truck Turn Times at Harvest Sites and Mill Facilities

Dowling, Tripp N. 02 June 2010 (has links)
The raw forest products transportation sector is inherently unique when compared to other transportation industries. The loggers and contractors who transport raw forest products are at a competitive disadvantage. Older equipment is also commonly used by the raw forest products transportation industry in harsh working environments. The average log truck age is 9.7 years while all trucks average only 3.9 years. Nineteen percent of log trucks are 15 years old or older while only 5.9% of all trucks are older than 8 years. Log trucks are regulated by both the Federal Motor Carrier Safety Administration and the state that the truck operates in, thus making interstate transportation more difficult. In addition to these challenges, there is a lack of information concerning efficiency and productivity improvement opportunities related to transporting forest products. This study evaluated truck turn times at both the harvesting site and mill facilities in order to identify important trucking productivity factors and efficiency improvement opportunities. Regression equations were created to estimate truck turn times at harvesting sites and mill facilities. Gross level studies found that 1268 truck turns at the tract scale averaged 1.40 hours while 576 truck turns at the mill scale averaged 0.56 hours. Elemental time studies at four harvesting locations found that log trucks were idle 32% of the time. Trucks spent 29% of time being loaded and 26% of the time waiting. Elemental time studies at mill facilities found that trucks were idle 27% of the time. Trucks spent the greatest amount of time unloading while unbinding was the second greatest contributor to turn times. Reductions in loading and waiting times can have significant effects on the overall turn time. Harvesting contractors could benefit from maintaining balanced harvesting crews. Estimates indicate that harvesting contractors could earn an additional profit of $106,500 over a period of five years by purchasing an additional skidder for those crews whose production is limited due to a lack of skidding capacity. It is estimated that if adding an additional trailer to harvesting crews would allow an additional 2 loads to be transported to the mill each day, harvesting crews could earn an additional $22,100 per year of profit. Road construction can also affect harvesting contractors profits. By minimizing road construction through the use of easements and improved pre-harvest planning, harvesting contractors could reduce road construction costs by as much as $14,000 per tract. With tools available to estimate truck turn around times, harvesting contractors, fleet managers, and truck drivers will be able to make more informed decisions regarding fleet management. This will enable those owning and operating trucks to operate in more efficient and profitable manners. The models created during this study will allow managers to estimate tract and mill turn times so as to better allocate trucking resources. / Master of Science
17

Regional Analysis of Log Truck Crashes in the United States between 2011 and 2015

Cole, Neila B. 07 June 2018 (has links)
Safe and efficient transportation of fiber is an essential component of the forest products supply chain, yet log truck crashes are believed to have increased across the United States. We examined two federally maintained databases to explore crash characteristics. Study objectives were to characterize log truck crashes nationally and regionally, and to compare log trucks to other similar trucks and assess differences. An analysis of 383 crashes involving log trucks across the U.S. were divided into four geographic regions for regional assessment. Results indicate that log trucks were significantly more likely to experience a rollover (p<.0001) as compared to other large trucks types. The average age of log trucks involved in fatal crashes (13 years) was significantly older (p=.0109) than overall average age for other large trucks (7.6 years). Log truck driver age was significantly different between region (p=.0269) with the highest average age in the Western region (53.4) and the lowest average age in the Midwest region (45.5). Calculations of crash rates revealed that the national average was 0.7 fatal log truck crashes per 100 million ft3 of wood harvested. The highest rate of log truck crashes occurred in the Southeast with 0.9 fatal crashes per 100 million ft3 of wood harvested. Between 2011 and 2015 fatal log truck crashes increased by 41%. Log tractor-trailer crashes increased 33% while all tractor-trailer crashes increased by 16%. Our findings reveal sufficient differences between log trucks and other large trucks to justify additional research regarding causation of crashes. / Master of Science / Safe and efficient transportation of raw materials to a processing facility is important to any industry, including the transportation of logs, pulpwood, and chips to forest products processing facilities. Although information regarding log truck crashes is clearly important, few studies have examined crashes specific to log trucks. Study objectives were to characterize log truck crashes nationally as well as regionally, and to compare log trucks to other similar trucks and assess differences. Analysis of data obtained from two federally maintained crash databases revealed that 383 crashes occurred over a 5-year period from 2011 to 2015 involving log trucks. Log trucks are more likely to experience a rollover during a crash with occurrences in 78% of fatal crashes. Both truck age and driver age differ significantly by region. Crash rates by state and region were calculated by comparing number of fatal crashes to the amount of wood harvested. The national average crash rate is 0.7 fatal log truck crashes per 100 million ft³ of wood harvested. The highest rate of log truck crashes is the Southeast with 0.9 fatalities per 100 million ft³ . Log tractor-trailer crashes increase by 33% between 2011 and 2015, while other large trucks increased by 16%. Log trucks are the oldest vehicles involved in fatal crashes, with an average age of 13 years, compared to the overall average for all trucks of 7.6 years. Our findings reveal sufficient differences between log trucks and other log truck to justify additional research regarding causation of crashes.
18

Estudo teórico da toxicidade dos PAHs por meio de ferramentas teóricas e sua importância na determinação do dano ambiental / Theoretical study of the toxicity of PAHs through theoretical tools and their importance in determining the environmental damage

Gobi, Bruna Danielle de Oliveira 17 November 2014 (has links)
Nas questões ambientais legais, muitas vezes a referência à toxicidade de uma substância é vaga. No entanto, essa informação é essencial para a determinação da extensão do dano. Para fazer a previsão desses valores para o benzeno e hidrocarbonetos policíclicos aromáticos (PAHs), componentes do petróleo, foi feito um estudo QSAR (Quantitative Structure Activity Relationship) por meio de cálculos de mecânica quântica e quimiometria. O objetivo foi construir modelos para prever os valores de coeficiente de partição n-octanol/água, Kow (n-octanol/water partition coefficient) além do estudo das toxicidades dos PAHs. Para este estudo, as geometrias de todas as moléculas foram otimizadas utilizando os métodos semiempíricos AM1, PM3, PM6 e PM7. Desses resultados ainda foram extraídos os descritores teóricos que foram utilizados para descrever os valores de log Kow. Entre todos aqueles calculados, os descritores: energia total, energia eletrônica, área, volume e massa molar foram escolhidos como os parâmetros para o estudo PLS (Partial Least Squares). Além disso, as toxicidades dos PAHs foram calculadas por meio do programa T.E.S.T (Toxicity Estimation Software Tool) disponibilizado gratuitamente pelo EPA (Environmental Protection Agency) e estimados por meio de modelo PLS e gráficos de correlação. Observou-se com esse estudo que todos os métodos apresentaram resultados bastante satisfatórios, uma vez que valores próximos de 1 foram obtidos tanto para o coeficiente de correlação interno, Q2, quanto para o externo, R2. / In the environmental legal issues, often the reference to toxicity of a substance is vague. However, this information is essential for determining the extent of damage. To forecast these values for benzene and polycyclic aromatic hydrocarbons (PAHs), petroleum components, one study QSAR (Quantitative Structure Activity Relationship) was done by calculation of quantum mechanics and chemometrics. The goal was to build models to predict the values of the partition coefficient n-octanol / water, Kow (n-octanol / water partition coefficient) beyond the study of the toxicity of PAHs. For this study, the geometries of all molecules were optimized using the semi-empirical methods AM1, PM3, PM6 and PM7. These theoretical results also descriptors that were used to describe the Log Kow values were extracted. Among those calculated descriptors: total energy, electronic energy, area, volume and molar mass were chosen as the parameters for the study PLS (Partial Least Squares). Furthermore, the toxicities of PAHs were calculated using the TEST (Toxicity Estimation Software Tool) program available free of charge by the EPA (Environmental Protection Agency) and estimated by PLS model and correlation charts. It was observed in this study that all the methods have shown promising results, since values near one were obtained for the standard and cross-validated correlation coefficients R2 and Q2.
19

Impactos do crescimento econômico sobre a distribuição de renda no Brasil (1970 -2006)

Castro Neto, Armando Affonso de January 2008 (has links)
90f. / Submitted by Suelen Reis (suziy.ellen@gmail.com) on 2013-03-06T17:22:22Z No. of bitstreams: 1 Armando%20%20Castroseg.pdf: 759340 bytes, checksum: f270484f2da0147eb7b48e262befcb22 (MD5) / Approved for entry into archive by Vania Magalhaes(magal@ufba.br) on 2013-03-14T12:38:51Z (GMT) No. of bitstreams: 1 Armando%20%20Castroseg.pdf: 759340 bytes, checksum: f270484f2da0147eb7b48e262befcb22 (MD5) / Made available in DSpace on 2013-03-14T12:38:51Z (GMT). No. of bitstreams: 1 Armando%20%20Castroseg.pdf: 759340 bytes, checksum: f270484f2da0147eb7b48e262befcb22 (MD5) Previous issue date: 2008 / Este trabalho analisa como as transformações estruturais trazidas pelo crescimento econômico impactam a distribuição de renda no Brasil. Considerando uma economia dualista, com um setor urbano, mais dinâmico, com maior renda e desigualdade, e um setor rural, mais atrasado, com menor renda e mais equânime, segue-se o modelo de análise de Langoni (1973). Neste modelo, busca-se investigar como mudanças na População Economicamente Ativa dos dois setores, referentes à participação do trabalho; à renda relativa e à distribuição interna de renda, decorrentes do crescimento econômico, vêm a impactar na distribuição pessoal de renda. Este estudo é realizado para o período de 1970 a 2006. Os resultados desta análise apontam que o ritmo de ampliação da desigualdade decai com o esfriamento do processo de industrialização e que a recente queda na desigualdade é decorrente, em parte, do próprio processo de desenvolvimento econômico. O modelo econométrico adotado corrobora a importância da urbanização sobre a distribuição de renda, e aponta que variáveis passíveis de controle por política econômica também influenciam significativamente a distribuição pessoal de renda. / Salvador
20

Estudo teórico da toxicidade dos PAHs por meio de ferramentas teóricas e sua importância na determinação do dano ambiental / Theoretical study of the toxicity of PAHs through theoretical tools and their importance in determining the environmental damage

Bruna Danielle de Oliveira Gobi 17 November 2014 (has links)
Nas questões ambientais legais, muitas vezes a referência à toxicidade de uma substância é vaga. No entanto, essa informação é essencial para a determinação da extensão do dano. Para fazer a previsão desses valores para o benzeno e hidrocarbonetos policíclicos aromáticos (PAHs), componentes do petróleo, foi feito um estudo QSAR (Quantitative Structure Activity Relationship) por meio de cálculos de mecânica quântica e quimiometria. O objetivo foi construir modelos para prever os valores de coeficiente de partição n-octanol/água, Kow (n-octanol/water partition coefficient) além do estudo das toxicidades dos PAHs. Para este estudo, as geometrias de todas as moléculas foram otimizadas utilizando os métodos semiempíricos AM1, PM3, PM6 e PM7. Desses resultados ainda foram extraídos os descritores teóricos que foram utilizados para descrever os valores de log Kow. Entre todos aqueles calculados, os descritores: energia total, energia eletrônica, área, volume e massa molar foram escolhidos como os parâmetros para o estudo PLS (Partial Least Squares). Além disso, as toxicidades dos PAHs foram calculadas por meio do programa T.E.S.T (Toxicity Estimation Software Tool) disponibilizado gratuitamente pelo EPA (Environmental Protection Agency) e estimados por meio de modelo PLS e gráficos de correlação. Observou-se com esse estudo que todos os métodos apresentaram resultados bastante satisfatórios, uma vez que valores próximos de 1 foram obtidos tanto para o coeficiente de correlação interno, Q2, quanto para o externo, R2. / In the environmental legal issues, often the reference to toxicity of a substance is vague. However, this information is essential for determining the extent of damage. To forecast these values for benzene and polycyclic aromatic hydrocarbons (PAHs), petroleum components, one study QSAR (Quantitative Structure Activity Relationship) was done by calculation of quantum mechanics and chemometrics. The goal was to build models to predict the values of the partition coefficient n-octanol / water, Kow (n-octanol / water partition coefficient) beyond the study of the toxicity of PAHs. For this study, the geometries of all molecules were optimized using the semi-empirical methods AM1, PM3, PM6 and PM7. These theoretical results also descriptors that were used to describe the Log Kow values were extracted. Among those calculated descriptors: total energy, electronic energy, area, volume and molar mass were chosen as the parameters for the study PLS (Partial Least Squares). Furthermore, the toxicities of PAHs were calculated using the TEST (Toxicity Estimation Software Tool) program available free of charge by the EPA (Environmental Protection Agency) and estimated by PLS model and correlation charts. It was observed in this study that all the methods have shown promising results, since values near one were obtained for the standard and cross-validated correlation coefficients R2 and Q2.

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