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The Lebesgue and Equivalent IntegralsLewis, Leslie L. 08 1900 (has links)
The purpose of this thesis is to present a study of the Lebesgue definite integral, defined in four different ways.
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Assessment and Improvement of Snow Datasets Over the United StatesDawson, Nicholas, Dawson, Nicholas January 2017 (has links)
Improved knowledge of the cryosphere state is paramount for continued model development and for accurate estimates of fresh water supply. This work focuses on evaluation and potential improvements of current snow datasets over the United States. Snow in mountainous terrain is most difficult to quantify due to the slope, aspect, and remote nature of the environment.
Due to the difficulty of measuring snow quantities in the mountains, the initial study creates a new method to upscale point measurements to area averages for comparison to initial snow quantities in numerical weather prediction models. The new method is robust and cross validation of the method results in a relatively low mean absolute error of 18% for snow depth (SD). Operational models at the National Centers for Environmental Prediction which use Air Force Weather Agency (AFWA) snow depth data for initialization were found to underestimate snow depth by 77% on average. Larger error is observed in areas that are more mountainous. Additionally, SD data from the Canadian Meteorological Center, which is used for some model evaluations, performed similarly to models initialized with AFWA data. The use of constant snow density for snow water equivalent (SWE) initialization for models which utilize AFWA data exacerbates poor SD performance with dismal SWE estimates.
A remedy for the constant snow density utilized in NCEP snow initializations is presented in the next study which creates a new snow density parameterization (SNODEN). SNODEN is evaluated against observations and performance is compared with offline land surface models from the National Land Data Assimilation System (NLDAS) as well as the Snow Data Assimilation System (SNODAS). SNODEN has less error overall and reproduces the temporal evolution of snow density better than all evaluated products. SNODEN is also able to estimate snow density for up to 10 snow layers which may be useful for land surface models as well as conversion of remotely-sensed SD to SWE.
Due to the poor performance of previously evaluated snow products, the last study evaluates openly-available remotely-sensed snow datasets to better understand the strengths and weaknesses of current global SWE datasets. A new SWE dataset developed at the University of Arizona is used for evaluation. While the UA SWE data has already been stringently evaluated, confidence is further increased by favorable comparison of UA snow cover, created from UA SWE, with multiple snow cover extent products. Poor performance of remotely-sensed SWE is still evident even in products which combine ground observations with remotely-sensed data. Grid boxes that are predominantly tree covered have a mean absolute difference up to 87% of mean SWE and SWE less than 5 cm is routinely overestimated by 100% or more. Additionally, snow covered area derived from global SWE datasets have mean absolute errors of 20%-154% of mean snow covered area.
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Desenvolvimento de epiderme equivalente sobre membrana do tipo transwell e membrana biopolimérica / Development of an epidermal equivalent model on a transwell and on a biopolymer scaffoldCatarino, Carolina Motter 11 May 2015 (has links)
Atualmente existe uma forte tendência mundial para o desenvolvimento de testes in vitro que supram o uso de animais em ensaios de avaliação de segurança. Em 1986 a Diretiva Europeia 86/609/EEC induziu a discussão mundial de redução de testes em animais e a 7ª emenda desta Diretiva, publicada em 2004, determinou a transferência dos ensaios para a avaliação de risco para sistema in vitro. Diferentes abordagens foram desenvolvidas para suprir essa necessidade como, por exemplo, a geração de equivalentes de epiderme, que foi considerada a mais promissora e extensamente investigada. Dois modelos de equivalentes de epiderme (EpiDermTM-MATTEK e EPISKINTM LORÉAL) comercialmente disponíveis foram validados pelo ECVAM (Centro Europeu para a Validação de Métodos Alternativos) e outros modelos de epiderme reconstruída estão sendo desenvolvidos em diferentes laboratórios de pesquisa do mundo. Esses dois modelos são recomendados no Guia 431 (Organização para cooperação e desenvolvimento econômico - OECD) que avalia in vitro a corrosão da pele. No Brasil esta prática ainda é inexistente, porém deverá ser implementada rapidamente para que atenda aos conceitos humanitários internacionais. Sendo assim, este projeto teve como objetivo criar, dentro dos princípios do Guia 431, um equivalente de epiderme e posterior otimização deste processo através da incorporação de uma membrana biopolimérica (PET e colágeno I) como suporte celular. O modelo de epiderme humana reconstruída consiste de um tecido epidérmico diferenciado tridimensionalmente a partir de queratinócitos humanos normais cultivados em um meio quimicamente definido na interface ar-líquido. A validação deste modelo para ensaios de avaliação do potencial corrosivo de substâncias foi realizada seguindo os princípios do Guia 431 da OECD, sendo que quatro substâncias da lista indicada pelo Guia foram testadas: duas corrosivas (Ácido Lático e Ácido Octanóico) e duas não corrosivas (2-bromo Etilbenzeno e Benzilacetona), assim como controles positivo (Acido acético) e negativo (NaCl 0,9%). Os resultados de viabilidade celular após 3 minutos e 1 hora de exposição às substâncias teste demostraram que o nosso modelo permite distinguir as substâncias entre corrosivas e não corrosivas, no entanto não permite a subcategorização das corrosivas em 1A ou 1B/C. Assim, nós demonstramos o potencial do nosso modelo como um método de teste relevante e confiável que pode ser usado para pesquisa e investigação de risco químico. Visando a otimização do modelo, testamos a incorporação de uma membrana biopolimérica eletrofiada de PET e colágeno tipo I como suporte para crescimento celular em substituição ao transwell. A análise histológica das membranas demonstrou que as mesmas são biocompativeis, permitindo adequada adesão e proliferação dos queratinócitos e dos fibroblastos, no entanto, não se observou uma diferenciação adequada com a formação de uma epiderme semelhante à humana (estratos basal, espinhoso, granuloso e córneo). Além disso, a falta de uniformidade e reprodutibilidade nos resultados indicam que é necessário uma otimização dos processos de fabricação das membranas e geração do equivalente epidérmico. Em perspectiva, este equivalente epidérmico poderá ser utilizado para pesquisa e avaliação de risco de fármacos, medicamentos, cosméticos, praguicidas, etc., contribuindo para a geração de métodos alternativos aos testes em animais e inserindo o Brasil na tendência internacional do desenvolvimento de testes para avaliação do risco. / Currently there is a strong global trend towards the development of in vitro tests that fulfill the use of animals in safety evaluation tests. In 1986, the European Directive 86/609/EEC led to the discussion of global reduction of animal testing and the 7th amendment of this Policy, published in 2004, ordered the transfer of the tests for risk assessment for in vitro system. Different approaches have been taking into account to achieve this goal, for example, the development of epidermal equivalents models, which have been considered the most promising and widely studied model. ECVAM (European Centre for the Validation of Alternative Methods) has validated two models of reconstructed epidermis (EpiDermTM - Mattek and EPISKINTM - L\'Oréal) that are commercially available and other models are being developed in different research laboratories in the world. These two models are recommended in Guide 431 (Organisation for Economic Cooperation and Development - OECD) for in vitro evaluation of skin corrosion. In Brazil, this practice is still lacking, but should be implemented quickly so that meets international humanitarian concepts. Therefore, this project aimed the creation, within the principles of Guide 431, of an epidermal equivalent and the optimization of this process through the incorporation of a biopolymer membrane (PET and collagen I) as cellular support. The reconstructed human epidermis (RHE) consists of a differentiated three-dimensional epidermal tissue reconstructed from normal human keratinocytes in a chemically defined medium and air liquid interface growth. The validation of this model for the assessment of skin corrosion potential of substances was performed following the principles of the OECD Guide 431, hereupon four substances from the list indicated by the Guide were tested: two corrosive (lactic acid and octanoic acid) and two non-corrosive (2-phenylethyl bromide and benzylacetone) and positive (acetic acid) and negative (NaCl 0.9%) controls. The cell viability results after 3 minutes and 1 hour of exposure to the test substances indicates that our model is capable of distinguishing the substances among corrosive and non-corrosive. Although they do not, allow the sub-categorization of corrosive in 1A or 1B/C. Thus, we have demonstrated that our model is a potentially relevant and a reliable test method that could be used in research and specifically for the investigation of chemical hazard. To optimize the model, we tested the incorporation of a biopolymer membrane composed of PET and type I collagen as support for cell growth, as a replacement of the transwell. Histological examination of membranes has shown that they are biocompatible, enabling adequate adhesion and proliferation of keratinocytes and fibroblasts. However, there was no adequate differentiation with the formation of a similar human epidermis (stratum basale, spinosum, granulosum and corneum). Moreover, the lack of uniformity and reproducibility of the results indicates that it is still necessary to optimize the membranes production process and the generation of the epidermal equivalent using the membranes as support. In perspective, the developed epidermal equivalent may be used for research and risk assessment of pharmaceuticals, medicines, cosmetics, chemicals, pesticides, among others. This directly contributes to the development of alternative methods able to substitute animal testing in Brazil and follows the international trend of development tests for risk assessment.
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Influência dos veículos pesados na capacidade de interseções rodoviárias / Influence of heavy vehicles on the capacity of rural intersectionsDemarchi, Sergio Henrique 23 January 1995 (has links)
Este trabalho avalia a influência de veículos de grande porte na capacidade de interseções rodoviárias em nível não semaforizadas, verificando as variações no comportamento de caminhões e ônibus durante manobras de cruzamento, em função de seu comprimento e de sua relação potência/peso. Foram realizadas análises das distribuições dos tempos de cruzamento e da aceitação de \"gaps\" por diferentes tipos de veículos, sendo utilizados modelos Logit para representar o comportamento desses veículos nos cruzamentos. Estes modelos serviram como base na elaboração de um simulador, para determinar a capacidade potencial das interseções e para calcular os fatores de conversão de veículos de grande porte em veículos de passageiro. / This study assesses the influence of heavy vehicles on the capacity of unsignalized rural intersections. This is done through the study of vehicle behavior during crossing maneuvers that can be attributed to length and power-to-weight ratio. Crossing time distributions and gap acceptance of diferent types of vehicles were analysed, and Logit models were used to represent their behavior. These models and a simulation model were used to determine the potencial capacity of intersections and to calculate factors to convert heavy vehicles into passenger vehicles.
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Hybrid simulation and optimization approach for green intermodal transportation problem with travel time uncertaintyHrusovsky, Martin, Demir, Emrah, Jammernegg, Werner, van Woensel, Tom 09 1900 (has links) (PDF)
The increasing volumes of road transportation contribute to congestion on road, which leads to delays and other negative impacts on the reliability of transportation. Moreover, transportation is one of the main contributors to the growth of carbon dioxide equivalent emissions, where the impact of road transportation is significant. Therefore, governmental organizations and private commercial companies are looking for greener transportation solutions to eliminate the negative externalities of road transportation. In this paper, we present a novel solution framework to support the operational-level decisions for intermodal transportation networks using a combination of an optimization model and simulation. The simulation model includes stochastic elements in form of uncertain travel times, whereas the optimization model represents a deterministic and linear multi-commodity service network design formulation. The intermodal transportation plan can be optimized according to different objectives, including costs, time and CO2e emissions. The proposed approach is successfully implemented to real-life scenarios where differences in transportation plans for alternative objectives are presented. The solutions for transportation networks with up to 250 services and 20 orders show that the approach is capable of delivering reliable solutions and identifying possible disruptions and alternatives for adapting the unreliable transportation plans.
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Influência dos veículos pesados na capacidade de interseções rodoviárias / Influence of heavy vehicles on the capacity of rural intersectionsSergio Henrique Demarchi 23 January 1995 (has links)
Este trabalho avalia a influência de veículos de grande porte na capacidade de interseções rodoviárias em nível não semaforizadas, verificando as variações no comportamento de caminhões e ônibus durante manobras de cruzamento, em função de seu comprimento e de sua relação potência/peso. Foram realizadas análises das distribuições dos tempos de cruzamento e da aceitação de \"gaps\" por diferentes tipos de veículos, sendo utilizados modelos Logit para representar o comportamento desses veículos nos cruzamentos. Estes modelos serviram como base na elaboração de um simulador, para determinar a capacidade potencial das interseções e para calcular os fatores de conversão de veículos de grande porte em veículos de passageiro. / This study assesses the influence of heavy vehicles on the capacity of unsignalized rural intersections. This is done through the study of vehicle behavior during crossing maneuvers that can be attributed to length and power-to-weight ratio. Crossing time distributions and gap acceptance of diferent types of vehicles were analysed, and Logit models were used to represent their behavior. These models and a simulation model were used to determine the potencial capacity of intersections and to calculate factors to convert heavy vehicles into passenger vehicles.
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Proporcionalidade e matemática financeira: uma abordagem tendo como princípio motivação e contextualização / Proportionality and financial mathematics: an approach based on the principles motivation and contextualizationAraújo, Tadeu Alexandre de 06 July 2017 (has links)
O presente trabalho contém algumas ideias, no nível do Ensino Médio, dos tópicos da Matemática, quais sejam proporcionalidade e Matemática Financeira. A apresentação de ambos os tópicos tem uma marca que é a resolução de problemas que consideramos motivadores, e que podem ser encontrados em múltiplos contextos. A seguinte linha de pensamento no desenvolvimento dos tópicos é adotada: em proporcionalidade, de início, problemas são apresentados e logo na sequência se foca o aspecto conceitual numa exposição minuciosa dos aspectos teóricos e práticos do tópico. O desenvolvimento da teoria é feita com detalhes desde a definição passando pelos resultados centrais até se chegar à caracterização de variáveis proporcionais. Notas explicativas são inseridas para evidenciar certos aspectos na rotina de estudantes e professores na situação de apreender/ensinar e que enriquecem o texto, um exemplo disso é a nota explicativa acerca dos limites de aplicação da teoria. A Matemática Financeira é apresentada a partir de problemas contextualizados e cujas resoluções são munidas de registros figurais que facilitam a apreensão conceitual. Em todo o desenvolvimento do tópico se discute o significado dos termos mais frequentes e há uma tentativa de evidenciar que a importância do tópico hoje reside no fato que se trata de uma ferramenta que subsidia a tomada de decisão financeira. / The present work contains some ideas, for the high school level, about the topics from Mathematics, which are Proportionality and Financial Mathematics. The presentation of both topics carries a mark that is the solution for the problems we consider motivating, and they can be found in several contexts. The following sequence of thought in thedevelpment of the topics is adopted: initially, in proportionality, problems are presented, and right afterwards, the conceptual aspect focuses the detailed demonstration of the theoretical and practical apspects of the topic. The theory development is carried out with details since the definition going across the central results till reaching the characterization of proportionals variables. Explaining notes are inserted to show certain aspects in the routines of students and teachers in the aprehending/teaching situation that enrich the text, and an example of this is the explaining note about the limits of the theory application. The Financial Mathematics is presented from the contextualized problems and their solutions are provided with pictorial records that facilitate the conceptual aprehension. The whole development of the topic discusses the meaning of the terms most frequently found and there is an attempt to evidence that the importance of the topic nowdays resides in the fact that such a tool subsidizes the financial decision making.
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Life Cycle Assessment Applied to 95 Representative U.S. FarmsRutland, Christopher T. 2011 August 1900 (has links)
Since World War II, concern for the environmental impacts of human activities has grown. Agriculture plays a significant role in several impact categories including global warming. Governments, including the U.S., have recently begun or are considering the regulation of greenhouse gas (GHG) emission to mitigate the global warming effect. Because agriculture accounts for a large portion of anthropogenic greenhouse gas emissions, it is necessary to establish a baseline measure of the GHG emission of U.S. agriculture at the farm level. The objective of this research is to estimate the GHG emission levels for multicrop farms in the U.S. and identify the major sources of GHG emissions in their supply chains.
To accomplish the objective, a partial life cycle assessment (LCA) methodology is used to establish a GHG baseline for the representative farms. LCA as defined by the International Organization for Standardization (ISO) includes four phases: goal and scope definition, inventory, impact assessment, and interpretation. It is a holistic approach that catalogues environmental impacts of all relevant processes at all stages of production, from raw material extraction to disposal. However, this study only catalogues impacts up to the farm gate. Partial LCAs are common in agriculture.
Emissions of three GHGs, CO2, CH4, and N2O, are inventoried for 95 U.S. farms. The results are characterized using their 100-year global warming potentials into CO2 equivalents. The CO2 equivalents are then normalized over four functional units: enterprises, acres or head, harvest units, and pounds of production.
The variation of GHG intensity between crops and farms is very large. However, it is clear that GHG intensity is affected by three characteristics: location, size, and irrigation practice. Crops grown in their associated regions tend to be more GHG efficient than those grown outside their associated regions. Also, crops grown on large farms tend to be more GHG efficient than the same crop grown on a small farm in the same area. Lastly, with the exceptions of cotton and soybeans, irrigated crops tend to be more GHG intensive than non-irrigated crops. These results combine to suggest that there may be a correlation between production efficiency and carbon efficiency.
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RC構造の繰り返し及び動的解析における格子等価連続体化法の適応性PHAMAVANH, Kongkeo, 伊藤, 睦, ITOH, Atsushi, 中村, 光, NAKAMURA, Hikaru, 田邉, 忠顕, TANABE, Tada-aki 08 1900 (has links)
No description available.
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The Influence of Snow Cover Variability and Tundra Lakes on Passive Microwave Remote Sensing of Late Winter Snow Water Equivalent in the Hudson Bay LowlandsToose, Peter 09 1900 (has links)
Current North American operational satellite passive microwave snow water equivalent (SWE) retrieval algorithms consistently underestimate SWE levels for tundra environments when compared to four years of regional snow surveys conducted in the Northwest Territories and northern Manitoba, Canada. Almost all contemporary SWE algorithms are based on the brightness temperature difference between the 37GHz and 19GHz frequencies found onboard both past and present spaceborne sensors. This underestimation is likely a result of the distribution and deposition of the tundra snow, coupled with the influence of tundra lakes on brightness temperatures at the 19GHz frequency. To better our understanding concerning the underestimation of passive microwave SWE retrievals on the tundra, Environment Canada collected in situ measurements of SWE, snow depth, and density at 87 sites within a 25km by 25km study domain located near Churchill, Manitoba in March 2006. Coincident multi-scale passive microwave airborne (70m & 500m resolution) and spaceborne (regridded to 12.5km & 25km resolution depending on frequency) data were measured at 6.9GHz, 19GHz, 37GHz and 89 GHz frequencies during the same time period.
The snow survey data highlighted small-scale localized patterns of snow distribution and deposition on the tundra that likely influences current SWE underestimation. Snow from the open tundra plains is re-distributed by wind into small-scale vegetated features and micro-topographic depressions such as narrow creekbeds, lake edge willows, small stands of coniferous trees and polygonal wedge depressions. The very large amounts of snow deposited in these spatially-constrained features has little influence on the microwave emission measured by large-scale passive microwave spaceborne sensors and is therefore unaccounted for in current methods of satellite SWE estimation. The analysis of the passive microwave airborne data revealed that brightness temperatures at the 19GHz were much lower over some tundra lakes, effectively lowering SWE at the satellite scale by reducing the 37-19GHz brightness temperature difference used to estimate SWE. The unique emission properties of lakes in the wide open expanse of the tundra plains, coupled with an insensitivity to the large amounts of SWE deposited in small-scale features provides an explanation for current passive microwave underestimation of SWE in the tundra environment.
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