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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.
191

An Approximate Model For Kanban Controlled Assembly Systems

Topan, Engin 01 September 2005 (has links) (PDF)
In this thesis, an approximation is proposed to evaluate the steady-state performance of kanban controlled assembly systems. The approximation is developed for the systems with two components making up an assembly. Then, it is extended to systems with more than two components. A continuous-time Markov model is aggregated keeping the model exact, and this aggregate model is approximated replacing some state-dependent transition rates with constant rates. Decomposition of the approximate aggregate model into submodels guarantees product-form steady-state distribution for each subsystem. Finally, submodels are combined in such a way that the size of the problem becomes independent of the number of kanbans. This brings about the computational advantage in solving the combined model using numerical matrix-geometric solution algorithms. Based on the numerical comparisons with simulation, the exact model, an approximate aggregate model and another approximation in a previous study in the literature, the approximation is observed to be good in terms of accuracy with respect to computational burden and has the potential to be a building block for the analysis of systems that are more complex but closer to real-life applications.
192

Membrane-based nanocalorimetry for low temperature studies with high resolution and absolute accuracy

Tagliati, Stella January 2011 (has links)
A differential, membrane-based nanocalorimeter has been designed and constructed for thermal studies of mesoscopic samples at low temperatures. The calorimeter is intended for sample masses from mg to sub-μg and a broad temperature range from above room temperature down to the sub-K region. It allows concurrent use of ac steady state and relaxation methods. Effort was spent to achieve good absolute accuracy to enable investigations of the electronic contribution to the heat capacity of superconductors. The calorimeter consists of a pair of cells, each of which is a stack of heaters and thermometer in the center of a silicon nitride membrane, in total giving a background heat capacity less than 100 nJ/K at 300 K, decreasing to 10 pJ/K at 1 K. The device has several distinctive features: i) The resistive thermometer, made of a GeAu alloy, displays a high sensitivity, dlnR/dlnT ≈ −1 over the entire temperature range. ii) The sample is placed in direct contact with the thermometer, which is allowed to self-heat. The thermometer can thus be operated at high dc current to increase the resolution. iii) Data are acquired with a set of eight synchronized lock-in amplifiers measuring dc, 1st and 2nd harmonic signals of heaters and thermometer. iv) Absolute accuracy is achieved via a novel variable-frequency fixed-phase technique in which the measurement frequency is automatically adjusted during ac-calorimetry measurements to account for the temperature variation of the sample specific heat and the device thermal conductance. The properties of the empty cell and the effect of the thermal link between sample and cell were analytically studied. Practical expressions for describing the frequency dependence of heat capacity, thermal conductance, and temperature oscillation amplitude of the system were formulated. Comparisons with measurements and numerical simulations show excellent agreement. Calibration procedures are simple, but care should be taken to minimize thermal radiation effects. The experimental setup is operated with self-regulation of heater powers and thermometer bias, including compensation to zero the differential dc signal. As a result its high resolution and compact format, the calorimeter is well suited for studies of phase transitions and phase diagrams as well as electronic specific heat. The performance of the device is demonstrated by a study of the superconducting state of a small lead crystal. / En differentiell, membran-baserad nanocalorimeter har designats och tillverkats för termiska studier av mesoskopiska prover vid låg temperatur. Kalorimetern är avsedd för provmassor från mg till sub-μg och ett brett temperaturområde från över rumstemperatur till under 1 K. Den tillåter samtidig användning av både ac steady state och relaxations-metod. Fokus har lagts på att uppnå en god absolut noggrannhet för att möjliggöra studier av det elektroniska bidraget till värmekapaciteten hos supraledare. Kalorimetern består av två celler, var och en uppbyggd som en stack med värmeelement och termometer i mitten av ett kiselnitrid-membran, med en total bakgrundsvärmekapacitet på mindre än 100 nJ/K vid 300 K, minskande till 10 pJ/K vid 1 K. Kalorimetern har flera särdrag: i) Den resistiva termometern, gjord av en GeAu legering, visar en hög känslighet, dlnR/dlnT ≈ −1 över hela temperaturområdet. ii) Provet placeras i direkt kontakt med termometern, som tillåts att självvärma. Termometern kan alltså användas vid hög dc ström för att öka upplösningen. iii) Mätningarna genomförs med en uppsättning av åtta synkroniserade lock-in förstärkare, som mäter dc, grundfrekvens och 1:a övertonen hos värme-element och termometer. iv) Absolut noggrannhet uppnås genom en ny variabel-frekvens konstant-fas teknik där mätfrekvensen justeras automatiskt under ac-kalorimetrimätningar för att kompensera temperaturberoendet hos provets specifika värmekapacitet och kalorimetercellens värmeledningsförmåga. Egenskaperna hos den tomma cellen och inverkan av den termiska länken mellan prov och cell studerades analytiskt. Praktiska uttryck för att beskriva frekvens beroendet hos systemets värmekapacitet, värmeledningsförmåga, och temperaturoscillationer har formulerats. Jämförelser mellan mätningar och numeriska simuleringar visar mycket bra överensstämmelse. Kalibreringsförfarandet är enkelt, men försiktighet bör vidtas för att minimera värmestrålningseffekter. Experimentuppställningen drivs med självreglering av värmare och termometer, inklusive kompensation för att nollställa den differentiella dc signalen. Som en följd av dess höga upplösning och kompakta format är kalorimetern väl lämpad för studier av fasövergångar och fasdiagram såväl som det elektroniska specifika värmet. Kalorimeterns prestanda demonstreras genom en studie av det supraledande tillståndet hos en liten blykristall. / At the time of the doctoral defense, the following paper was unpublished and had a status as follows: Paper 5: Accepted.
193

A study into the permeability and compressibility of Australian bagasse pulp

Rainey, Thomas James January 2009 (has links)
This is an experimental study into the permeability and compressibility properties of bagasse pulp pads. Three experimental rigs were custom-built for this project. The experimental work is complemented by modelling work. Both the steady-state and dynamic behaviour of pulp pads are evaluated in the experimental and modelling components of this project. Bagasse, the fibrous residue that remains after sugar is extracted from sugarcane, is normally burnt in Australia to generate steam and electricity for the sugar factory. A study into bagasse pulp was motivated by the possibility of making highly value-added pulp products from bagasse for the financial benefit of sugarcane millers and growers. The bagasse pulp and paper industry is a multibillion dollar industry (1). Bagasse pulp could replace eucalypt pulp which is more widely used in the local production of paper products. An opportunity exists for replacing the large quantity of mainly generic paper products imported to Australia. This includes 949,000 tonnes of generic photocopier papers (2). The use of bagasse pulp for paper manufacture is the main application area of interest for this study. Bagasse contains a large quantity of short parenchyma cells called ‘pith’. Around 30% of the shortest fibres are removed from bagasse prior to pulping. Despite the ‘depithing’ operations in conventional bagasse pulp mills, a large amount of pith remains in the pulp. Amongst Australian paper producers there is a perception that the high quantity of short fibres in bagasse pulp leads to poor filtration behaviour at the wet-end of a paper machine. Bagasse pulp’s poor filtration behaviour reduces paper production rates and consequently revenue when compared to paper production using locally made eucalypt pulp. Pulp filtration can be characterised by two interacting factors; permeability and compressibility. Surprisingly, there has previously been very little rigorous investigation into neither bagasse pulp permeability nor compressibility. Only freeness testing of bagasse pulp has been published in the open literature. As a result, this study has focussed on a detailed investigation of the filtration properties of bagasse pulp pads. As part of this investigation, this study investigated three options for improving the permeability and compressibility properties of Australian bagasse pulp pads. Two options for further pre-treating depithed bagasse prior to pulping were considered. Firstly, bagasse was fractionated based on size. Two bagasse fractions were produced, ‘coarse’ and ‘medium’ bagasse fractions. Secondly, bagasse was collected after being processed on two types of juice extraction technology, i.e. from a sugar mill and from a sugar diffuser. Finally one method of post-treating the bagasse pulp was investigated. The effects of chemical additives, which are known to improve freeness, were also assessed for their effect on pulp pad permeability and compressibility. Pre-treated Australian bagasse pulp samples were compared with several benchmark pulp samples. A sample of commonly used kraft Eucalyptus globulus pulp was obtained. A sample of depithed Argentinean bagasse, which is used for commercial paper production, was also obtained. A sample of Australian bagasse which was depithed as per typical factory operations was also produced for benchmarking purposes. The steady-state pulp pad permeability and compressibility parameters were determined experimentally using two purpose-built experimental rigs. In reality, steady-state conditions do not exist on a paper machine. The permeability changes as the sheet compresses over time. Hence, a dynamic model was developed which uses the experimentally determined steady-state permeability and compressibility parameters as inputs. The filtration model was developed with a view to designing pulp processing equipment that is suitable specifically for bagasse pulp. The predicted results of the dynamic model were compared to experimental data. The effectiveness of a polymeric and microparticle chemical additives for improving the retention of short fibres and increasing the drainage rate of a bagasse pulp slurry was determined in a third purpose-built rig; a modified Dynamic Drainage Jar (DDJ). These chemical additives were then used in the making of a pulp pad, and their effect on the steady-state and dynamic permeability and compressibility of bagasse pulp pads was determined. The most important finding from this investigation was that Australian bagasse pulp was produced with higher permeability than eucalypt pulp, despite a higher overall content of short fibres. It is thought this research outcome could enable Australian paper producers to switch from eucalypt pulp to bagasse pulp without sacrificing paper machine productivity. It is thought that two factors contributed to the high permeability of the bagasse pulp pad. Firstly, thicker cell walls of the bagasse pulp fibres resulted in high fibre stiffness. Secondly, the bagasse pulp had a large proportion of fibres longer than 1.3 mm. These attributes helped to reinforce the pulp pad matrix. The steady-state permeability and compressibility parameters for the eucalypt pulp were consistent with those found by previous workers. It was also found that Australian pulp derived from the ‘coarse’ bagasse fraction had higher steady-state permeability than the ‘medium’ fraction. However, there was no difference between bagasse pulp originating from a diffuser or a mill. The bagasse pre-treatment options investigated in this study were not found to affect the steady-state compressibility parameters of a pulp pad. The dynamic filtration model was found to give predictions that were in good agreement with experimental data for pads made from samples of pretreated bagasse pulp, provided at least some pith was removed prior to pulping. Applying vacuum to a pulp slurry in the modified DDJ dramatically reduced the drainage time. At any level of vacuum, bagasse pulp benefitted from chemical additives as quantified by reduced drainage time and increased retention of short fibres. Using the modified DDJ, it was observed that under specific conditions, a benchmark depithed bagasse pulp drained more rapidly than the ‘coarse’ bagasse pulp. In steady-state permeability and compressibility experiments, the addition of chemical additives improved the pad permeability and compressibility of a benchmark bagasse pulp with a high quantity of short fibres. Importantly, this effect was not observed for the ‘coarse’ bagasse pulp. However, dynamic filtration experiments showed that there was also a small observable improvement in filtration for the ‘medium’ bagasse pulp. The mechanism of bagasse pulp pad consolidation appears to be by fibre realignment. Chemical additives assist to lubricate the consolidation process. This study was complemented by pulp physical and chemical property testing and a microscopy study. In addition to its high pulp pad permeability, ‘coarse’ bagasse pulp often (but not always) had superior physical properties than a benchmark depithed bagasse pulp.
194

Probing metal and substrate binding to metallo-[beta]-lactamase ImiS from Aeromonas sobria using site-directed mutagenesis

Chandrasekar, Sowmya. January 2004 (has links)
Thesis (M.S.)--Miami University, Dept. of Chemistry and Biochemistry, 2004. / Title from first page of PDF document. Includes bibliographical references (p. 57-64).
195

MATHEMATICAL MODELING OF <i>CLOSTRIDIUM THERMOCELLUM’S</i> METABOLIC RESPONSES TO ENVIRONMENTAL PERTURBATION

Adotey, Bless 01 January 2011 (has links)
Clostridium thermocellum is a thermophilic anaerobe that is capable of producing ethanol directly from lignocellulosic compounds, however this organism suffers from low ethanol tolerance and low ethanol yields. In vivo mathematical modeling studies based on steady state traditional metabolic flux analysis, metabolic control analysis, transient and steady states’ flux spectrum analysis (FSA) were conducted on C. thermocellum’s central metabolism. The models were developed in Matrix Laboratory software ( MATLAB® (The Language of Technical Computing), R2008b, Version 7.7.0.471)) based on known stoichiometry from C. thermocellum pathway and known physical constraints. Growth on cellobiose from Metabolic flux analysis (MFA) and Metabolic control analysis (MCA) of wild type (WT) and ethanol adapted (EA) cells showed that, at lower than optimum exogenous ethanol levels, ethanol to acetate (E/A) ratios increased by approximately 29% in WT cells and 7% in EA cells. Sensitivity analyses of the MFA and MCA models indicated that the effects of variability in experimental data on model predictions were minimal (within ±5% differences in predictions if the experimental data varied up to ±20%). Steady state FSA model predictions showed that, an optimum hydrogen flux of ~5mM/hr in the presence of pressure equal to or above 7MPa inhibits ferrodoxin hydrogenase which causes NAD re-oxidation in the system to increase ethanol yields to about 3.5 mol ethanol/mol cellobiose.
196

Modelling of Safety Concepts for Autonomous Vehicles using Semi-Markov Models

Bondesson, Carl January 2018 (has links)
Autonomous vehicles is soon a reality in the every-day life. Though before it is used commercially the vehicles need to be proven safe. The current standard for functional safety on roads, ISO 26262, does not include autonomous vehicles at the moment, which is why in this project an approach using semi-Markov models is used to assess safety. A semi-Markov process is a stochastic process modelled by a state space model where the transitions between the states of the model can be arbitrarily distributed. The approach is realized as a MATLAB tool where the user can use a steady-state based analysis called a Loss and Risk based measure of safety to assess safety. The tool works and can assess safety of semi-Markov systems as long as they are irreducible and positive recurrent. For systems that fulfill these properties, it is possible to draw conclusions about the safety of the system through a risk analysis and also about which autonomous driving level the system is in through a sensitivity analysis. The developed tool, or the approach with the semi-Markov model, might be a good complement to ISO 26262.
197

Efeito do nível do treinamento aeróbio na determinação do limite superior do domínio pesado no ciclismo /

Caritá, Renato Aparecido Corrêa. January 2011 (has links)
Orientador: Camila Coelho Greco / Banca: Fabrizio Caputo / Banca: Dalton Muller Pessoa Filho / Resumo: O principal objetivo deste estudo foi analisar e comparar as respostas metabólicas e cardiorrespiratórias durante o exercício realizado na MLSS e PC em indivíduos com diferentes níveis de treinamento aeróbio no ciclismo. Participaram do estudo 7 ciclistas (C) bem treinados, especializados em provas de estrada e 9 sujeitos não treinados (NT), sem experiência prévia de treinamento no ciclismo. Os voluntários realizaram em dias diferentes os seguintes testes, em um cicloergômetro: 1) teste incremental até a exaustão para a determinação do limiar anaeróbio (Lan), consumo máximo de oxigênio ( O2max) e da intensidade correspondente ao O2max (I O2max); 2) 2 a 4 testes de carga constante de 30 minutos em diferentes intensidades para a determinação da máxima fase estável de lactato sanguíneo (MLSS); 3) 3 testes de carga constante a 95, 100 e 110% I O2max até a exaustão voluntária para a determinação da potência crítica (PC), e; 4) um teste de carga constante até a exaustão na PC. A MLSS foi considerada como a maior intensidade de exercício onde a concentração de lactato não aumentou mais do que 1 mM entre o 10o e o 30o minuto de exercício. Os valores individuais de potência (95, 100 e 110% I O2max) e seu respectivo tempo máximo de exercício (tlim) foram ajustados a partir do modelo hiperbólico de 2 parâmetros para determinação da PC. A PC para ambos os grupos C (318 ± 29W) e NT (200 ± 33W) foi maior significantemente do que a MLSS para os C (288 ± 35W) e NT (169 ± 34W). A MLSS e a PC foram significantemente maiores no grupo C. Em valores relativos ao O2max a MLSS foi maior no grupo C (83 ± 7%) do que no grupo NT (79 ± 6), porém a PC foi similar entre os grupos (91 ± 5% e 90 ± 5%, respectivamente). Da mesma forma, o consumo de oxigênio na PC ( O2PC) foi significantemente maior do que na MLSS ( O2MLSS) nos grupos NT... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The objective of this study was to analyze and to compare metabolic and cardiorrespiratory responses durin the exercise performed at MLSS and CP in subjects with different aerobic trainning levels in cycling. Participated of this study, 7 well trained cyclists (C), specialized in road events and 9 non-trained subjects (NT), without previous training experience in cycling. Ths subjects performed the following protocols in different days in cyclergometer: 1) incremental test until exhaustion to determine anaerobic threshold (AT), maximal oxygen uptake ( O2max) and the intensity at O2max (I O2max); 2) 2 to 4 constant workload tests in different intensities to determine maximal lactate steadystate (MLSS); 3) 3 constant workload tests at 95, 100 e 110% I O2max until exhaustion to determine critical power (CP), and; 4) constant workload test until exhaustion at CP. MLSS was considered the highest exercise intensity at which the blood lactate concentration did not increase for more than 1 mM between 10th and 30th minute of the exercise. The individual values of power (95, 100 e 110% I O2max) and the respective times (tlim) were adjusted using the hyperbolic model with parameteres to determine CP. CP for C (318 ± 29W) and NT (200 ± 33W) was significantly higher than MLSS in C (288 ± 35W) and NT (169 ± 34W). MLSS and PC were significantly higher in C group. In values relative to O2max, the MLSS was significantly higher in C (83 ± 7%) than NT (79 ± 6), however CP was similar between groups (91 ± 5% and 90 ± 5%, respectively). In the same way, the oxygen uptake at CP ( O2PC) was significantly higher than at MLSS ( O2MLSS) for NT (2627 + 519 e 2323 ± 460 mL.min-1, 11%) e C (3607 ± 505 e 3953 ± 466 mL.min-1, 8%). The slow component at CP in C (375 ± 164 ml.min-1) was similar to NT (412 ± 175 ml.min-1). At this condition, the O2max was not attained (C - 93 ± 5%; NT - 96 ± 7%)... (Complete abstract click electronic access below) / Doutor
198

[en] A COMPUTER IMPLEMENTATION FOR FINITE ELEMENT ANALYSIS OF UNCONFINED STEADY STATE FLOW PROBLEMS / [es] IMPLEMENTACIÓN COMPUTACIONAL PARA MODELOS DE EXCAVACIÓN Y FLUJO PERMANENTE NO CONFINADO / [pt] IMPLEMENTAÇÃO COMPUTACIONAL PARA MODELAGEM DE ESCAVAÇÃO E FLUXO PERMANENTE NÃO-CONFINADO

AMERICO BUSTAMANTE CHACON 19 April 2001 (has links)
[pt] O presente trabalho apresenta a implementação computacional pelo método dos elementos finitos de procedimentos para análise de problemas de escavação e de fluxo permanente bidimensional, não confinado, para solos saturados. Tais procedimentos, particularmente indicados para investigação do comportamento mecânico/hidráulico de barragens de terra, vem completar o trabalho iniciado por Parra (1996) para análise do comportamento de barragens sob carregamentos estático e sísmico. Foram implementadas duas técnicas para simulação de escavações, obtendo-se, em ambas, resultados numéricos praticamente idênticos. O procedimento para análise de fluxo permanente foi baseado na proposição de Bathe e Khoshgoftarr (1979), a qual considera a situação de fluxo não-confinado como problema não linear, porém conservando a configuração original da malha de elementos finitos. Os resultados numéricos obtidos neste trabalho foram detalhadamente comparados com os valores publicados na literatura, numéricos ou analíticos, como forma de assegurar a confiabilidade das implementações computacionais. A previsão do comportamento da barragem de terra Macusani, a ser construída no Peru, foi estudada neste trabalho, nos aspectos referentes às fases de escavação, construção, primeiro enchimento do reservatório e determinação da superficie de infiltração de fluxo permanente. Os resultados assim obtidos podem ser eventualmente úteis no detalhamento do projeto final da obra. / [en] This work presents a computer implementation for finite element analysis of excavation problems and unconfined steady state flow through saturated soils. These computer routines are particularly useful for the study of earth dams and they were written with the aim to pursue the development of a numerical model (Parra, 1996) devised to investigate the behavior of earth dams under static and seismic loading. Two techniques were implemented for excavation simulations, with both yielding the some numerical results. For the unconfined fluid flow problem the technique proposed by Bathe and Khoshgoftaar (1979) was adopted, which recasts the problem in a non-linear form but keeps the same basic finite element mesh. The results computed in this research were compared with other analytical and numerical values published in the literature, in order to ensure, as much as possible, the feasibility and efficiency of the computer implementations. The behavior prediction of the Macusani earth dam, to be built in Peru, was also studied in this research, focusing on several aspects related to its planned construction: the excavation, the construction itself and the first reservoir filling. This results may eventually be useful for the final engineering design of the Macusani dam. / [es] El presente trabajo presenta la implementación computacional de procedimentos para análisis de problemas de excavación y de flujo permanente bidimensional, para suelos saturados utilizando el método de elementos finitos. Tales procedimentos, particularmente indicados para la investigación del comportamiento mecánico/hidráulico de represas, completa el trabajo iniciado por Parra(1996) para análisis del comportamiento de represas bajo sobrecarga estática y sísmica. Se implementaron dos técnicas para simulación de excavaciones, obteniendo, en ambas, resultados numéricos prácticamente idénticos. El procedimento para análisis de flujo permanente tubo como base la propuesta de Bathe y Khoshgoftarr (1979), que considera la situación de flujo no confinado como problema no lineal, pero conservando la configuración original de la malla de elementos finitos. Los resultados numéricos obtenidos em este trabajo fueron detalladamente comparados con los valores publicados en la literatura, numéricos o analíticos, para asegurar la confiabilidad de las implementaciones computacionales. La previsión del comportamiento de la represa de Macusani, que será construida en Perú, fue estudiada en este trabajo, especifícamente los aspectos vinculados a las fases de excavación, construcción y determinación de la superficie de infiltración de flujo permanente. Los resultados obtenidos pueden ser eventualmente útiles en el proyecto final de la obra.
199

Metodologia para quantificação e acompanhamento de indicadores-chave de desempenho operacional

Giaquinto, Cláudia Daniela Melo January 2017 (has links)
Indicadores-chave de desempenho (KPIs) exercem um papel de extrema importância na indústria de processos, auxiliando na tomada de decisão. No entanto, para serem representativos precisam ser calculados de forma confiável. O presente trabalho propôs uma metodologia para o cálculo destes KPIs com base em técnicas de detecção do estado estacionário, remoção de ruído, propagação de erros e análise de sensibilidade. Estes KPIs foram apresentados, de acordo com o que consta na literatura, em uma nova ferramenta gráfica de acompanhamento proposta pelos autores, denominada StatSSCandlePlot. O StatSSCandlePlot apresenta os KPIs no padrão candlestick, que é bastante utilizado no mercado de ações, incluindo informações adicionais. O grande diferencial do StatSSCandlePlot é que os indicadores e suas respectivas propriedades exibidas são calculadas a partir de técnicas que englobam o tratamento de dados e análises estatísticas. A metodologia proposta foi aplicada em um estudo de caso de um chuveiro contendo dois princípios de aquecimento, gás e energia elétrica. Para este estudo, foi criado o Índice de Qualidade do Banho (IQB), que é um indicador dependente da temperatura e da vazão de saída, cujos dados foram avaliados em três cenários distintos, o primeiro quando o sistema é submetido a distúrbios na vazão, no segundo ocorre uma queda na temperatura da água fria e no último, o IQB foi avaliado quando o sistema foi submetido a distúrbios na vazão sob uma nova estratégia de controle da planta. A partir do StatSSCandlePlot, foi possível identificar as tendências do indicador nos diferentes cenários, a parcela de cada janela no estado estacionário, os valores a serem considerados do indicador e, de forma complementar, identificar a variável que mais influenciou na variação do indicador, através da análise de sensibilidade. / Key performance indicators (KPIs) play an extremely important role in the process industry, aiding in decision-making. However, to be representative they need to be calculated reliably. The present work proposed a methodology for the calculation of these KPIs based on steady state detection, noise removal, error propagation and sensitivity analysis techniques. These KPIs were presented, as far as it is known, in a new graphical KPIs monitoring tool proposed by the authors, called StatSSCandlePlot. StatSSCandlePlot introduces KPIs in the candlestick standard, which is widely used in the stock market, including additional information. The major difference of StatSSCandlePlot is that the indicators and their respective displayed properties are calculated from techniques that encompass data processing and statistical analysis. The proposed methodology was applied in a case study of a shower containing two principles of heating, gas and electric energy. For this study the Bath Quality Index (BQI) was created, which is a temperature and output flow dependent indicator, whose data were evaluated in three different scenarios, the first one when the system was submitted to flow disturbances, in the second one, a decrease in the temperature of the cold water and in the last one, the IQB was evaluated when the system was submitted to disturbances in the flow under a new strategy of control of the plant. From the StatSSCandlePlot, it was possible to identify the trends of the indicator in the different scenarios, the portion of each window in the steady state, the values to be considered in the indicator and, in a complementary way, to identify the variable that most influenced the variation of the indicator, through the sensitivity analysis.
200

Natureza e crescimento econômico : como uma mudança de paradigma pode contribuir para uma economia ecologicamente responsável

Schütz, Felipe January 2017 (has links)
O presente trabalho discute como uma mudança de paradigma econômico pode contribuir para uma economia ecologicamente responsável. Em linha com esse propósito num primeiro momento são apresentados os sinais da necessidade dessa mudança. Nessa primeira parte são apresentadas algumas das insuficiências das ferramentas econômicas tradicionais para uma harmonização com o meio ambiente. Num segundo momento são discutidas ideias alternativas para a abordagem da relação entre crescimento econômico e meio ambiente: economia e entropia, estado estacionário e prosperidade sem crescimento. Nessas discussões foi dada ênfase aos estudos dos economistas Nicholas Georgescu-Roegen, Herman Daly e Timothy Jackson. Na parte seguinte são discutidas as implicações éticas para o desenvolvimento de um modelo econômico ecologicamente responsável. Por fim, por meio do estudo da Comissão Stiglitz-Sen-Fitoussi, do Índice de Progresso Social e de Índices de Felicidade argumenta-se como novas medidas de desenvolvimento econômico, social e ambiental podem contribuir para um paradigma econômico ecologicamente responsável. / This study discuss how a change of economic paradigm could contribute to an environmentally responsible economy. In order to do this, at first, the signs of the need for this paradigm shift are presented. On this matter the shortcomings of traditional economic tools for harmonization with the environment are analysed. Secondly, alternative ideias to address the relationship between economic growth and the environment, such as economy and entropy, steady state, and prosperity without growth are discussed. In these discussions the studies of economists like Nicholas Georgescu-Roegen, Herman Daly and Timothy Jackson, are emphasized. In the next part of this study the ethical implications for the development of an environmentally responsible economic model are approached. Finally, through the study of the Stiglitz-Sen-Fitoussi Comssion, the Social Progress Index and Happiness Index, it is shown how new measures of economic, social and environmental development could contribute to an environmentally responsible economic paradigm.

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