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Tamanhos pictóricos percebidos sobre gradientes de textura desenhados e fotografados após exposições breves / Pictorial size perceived under line-drawing and photographed texture gradient after brief exposuresBernardino, Leonardo Gomes 11 September 2012 (has links)
O presente estudo teve por objetivo investigar a dinâmica temporal da percepção de tamanho de objetos inseridos em gradientes de textura, provenientes de desenho gerado computacionalmente (gradiente de perspectiva) e de fotografia com elementos naturais (gradiente fotografado). Além disso, verificou-se a ocorrência e padrão dos movimentos oculares nestas condições. Para isso, foram realizados 2 experimentos. No primeiro experimento, dois círculos negros eram apresentados no meridiano vertical e a tarefa dos 96 participantes foi indicar em qual parte do campo visual, superior ou inferior, foi apresentado o maior círculo. Usando o método das escadas duplas, estes círculos eram apresentados brevemente (50, 100, 150 ou 200 ms) em três condições de fundos de tela (sem textura, gradiente de perspectiva ou gradiente fotografado). Foram calculados a inclinação da função psicométrica e o ponto de igualdade subjetivo (PIS) como medidas da sensibilidade discriminativa e da distorção perceptiva, respectivamente. Os resultados mostraram que os participantes discriminaram melhor o tamanho dos estímulos à medida que o tempo de exposição aumentava, independentemente do gradiente de textura. A análise do PIS revelou que há uma forte distorção do tamanho aos 100 ms para o gradiente de perspectiva e aos 150 ms para o gradiente fotografado. No segundo experimento, 24 participantes realizaram uma tarefa semelhante ao do primeiro experimento e utilizou-se um eye tracker para registrar o movimento ocular. Os resultados mostraram que, em apresentações de 150 e 200 ms, os movimentos oculares ocorreram em menos de 10% das tentativas em todos os fundos de tela. Isto indica que a redução das distorções de tamanho após os 100 ms observada no primeiro experimento não é explicada completamente pela alocação da atenção. Tomados em conjunto, estes resultados sugerem que o processamento e integração das informações de tamanho e profundidade são mediados principalmente por mecanismos bottom-up. Ademais, em uma condição de menor restrição temporal (1500 ms), a presença de informações de profundidade afetou a dimensão espacial das fixações e sacadas, mas não a dimensão temporal. Os participantes olharam preferencialmente para o estímulo apresentado no campo visual superior, o que indica que a atenção foi alocada às posições de maior profundidade. Os resultados também indicaram que os estímulos maiores capturaram tanto a atenção transitória quanto a atenção sustentada. Assim, este estudo permitiu um maior conhecimento sobre os mecanismos perceptivos e atentivos envolvidos no processamento das informações de tamanho e de profundidade. / This study aimed to investigate the temporal dynamics of object size perception under texture gradients from line-drawing (perspective gradient) and photograph with natural elements (photographed gradient). Additionally, it was analyzed the occurrence and the pattern of eye movements in these conditions. For this, we carried out 2 experiments. In the first experiment, two black circles were displayed in the vertical meridian and 96 participants reported whether the bigger one was presented at the lower or upper visual field. By using double staircase psychophysics method, these circles were briefly presented (50, 100, 150 or 200 ms) in three background conditions (no texture, perspective gradient or photographed gradient). The slope of the psychometric function and the points of subjectivity equality (PSE) were calculated and used as discrimination sensitivity and size distortion measures, respectively. The results showed a greater sensitivity to size discrimination as exposure time increased, regardless the texture gradient. The analysis of PSE indicated greater size distortions in perspective gradient at 100 ms and in photographed gradient at 150 ms. In the second experiment, 24 participants performed a task similar to that in Experiment 1 while an eye tracker recorded their eye-movements. The results showed that, at 150 and 200 ms, eye movements occurred in less than 10% of trials in all backgrounds. It indicates that the size distortion reduction after 100 ms observed in the first experiment cannot be fully explained by attention allocation. Taken together, these results suggest that the process and integration of size and depth information are mainly mediated by bottom-up mechanism. Moreover, in a less time constrain condition (1500 ms), depth cues affected the spatial measures of fixations and saccades, but not the temporal ones. The participants looked more frequently at the stimulus on the upper visual field, indicating that attention has been allocated to positions of greater depth. The results also indicated that large stimulus capture both transient and sustained attention. Thus, this study provides a better understanding of perceptual and attentive mechanisms involved in size and depth process.
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Integração das estratégias de sustentabilidade: \"top-down\" e \"bottomup\" como ferramentas de aprendizagem para a alfabetização ecológica no Ensino Médio / Integration of sustainability strategies: \"top-down\" and \"bottom-up\" as learning tools for ecological literacy in high schoolSilva, Tainá Gouvêa Galvão 03 August 2018 (has links)
O desenvolvimento sustentável no final do século XX surgiu para expressar preocupações com graves problemas que causam riscos a vida no planeta. O uso do planeta de forma sustentável exigirá diferentes estratégias de sustentabilidade. Neste sentido têm-se as estratégias que abordam o nível mais elevado do ecossistema referidas como Top-down e as estratégias que abordam componentes locais ou regionais referidas como bottom-up. A escola traz essa compreensão nos conceitos e fenômenos ecológicos. No entanto, a compreensão dessas abordagens com apoio interdisciplinar faz com que o aluno entenda os fenômenos ecológicos de forma mais crítica. Assim, para um aprendizado motivador, o professor pode utilizar como recurso didático além dos espaços formais de educação também espaços não formais de educação, ou seja, aulas de campo em ambientes naturais. Com o intuito de promover no ensino de ecologia a alfabetização ecológica dos alunos no Ensino Médio, este trabalho elaborou uma proposta didática com apoio interdisciplinar (Biologia, Língua Portuguesa e Geografia) e com ênfase nas estratégias Top-down e bottom-up abordadas tanto em espaços formais quanto não formais de educação. O método de ensino em espaço formal de educação apesar de estar estruturado didaticamente para abranger a ecologia não se apresentou motivadora ao aluno e muitos dos conceitos e fenômenos ecológicos não foram assimilados por eles. Em contrapartida, a integração interdisciplinar em associação com as estratégias de Top-down e bottom-up em espaços não formais de educação foi motivadora para o aluno melhorando o seu desempenho com relação à assimilação dos conceitos e fenômenos biológicos promovendo a alfabetização ecológica dos alunos. Espera-se com esse trabalho ter contribuído para o ensino e aprendizagem do tema sustentabilidade através da promoção da alfabetização ecológica dos alunos de Biologia no Ensino Médio em escolas públicas com a formação de cidadãos mais conscientes e críticos em assuntos ambientais. / Sustainable development in the late 20th century has emerged to express concerns about serious life-threatening problems on the planet. The use of the planet in a sustainable way will require different sustainability strategies. In this sense we have the strategies that approach the highest level of the ecosystem referred to as \"top-down\" and the strategies that approach local or regional components referred to as \"bottom-up\". The school brings this understanding into concepts and ecological phenomena. However, understanding these approaches with interdisciplinary support makes the student understand ecological phenomena more critically. Thus, for a motivating learning, the teacher can use as a didactic resource beyond the formal spaces of education also non-formal spaces of education, that is, field lessons in natural environments. In order to promote ecological literacy among students in high school, this work elaborated a didactic proposal with interdisciplinary support (Biology, Portuguese Language and Geography) and with emphasis on top-down and bottom-up strategies addressed in both formal and non-formal education settings. The method of teaching in formal educational space despite being structured to cover ecology did not present itself as motivating to the student and many concepts and ecological phenomena were not assimilated by them. In contrast, interdisciplinary integration in association with top-down and bottom-up strategies in non-formal education spaces was motivating for the student to improve his performance in relation to the assimilation of concepts and biological phenomena by promoting literacy of the students. It is hoped that this work contributed to the teaching and learning of the sustainability theme through the promotion of the ecological literacy of Biology students in High School in public schools with the formation of citizens more conscious and critical in environmental issues.
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Sistemas de gestão integrados como indutor para a sustentabilidade: uma análise do impacto no desempenho das organizações baseado no Triple Bottom Line. / Integrated management systems as a driver for sustainability: an analysis of organizations performane impact based on Triple Bottom Line.Nadae, Jeniffer de 20 April 2016 (has links)
O objetivo deste trabalho é analisar o impacto dos Sistemas de Gestão Integrados (SGI) no desempenho organizacional sob a óptica do Triple Bottom Line (TBL), verificando se esta implementação auxilia a empresa a se tornar mais sustentável. A abordagem multi-método utilizada está dividida em três partes. A primeira compreende uma revisão sistemática da literatura, tendo como base a abordagem bibliométrica. A base de dados escolhida para a seleção dos artigos que compõem a amostra foi a ISI Web of Knowledge (Web of Science). As análises conduzidas sugerem lacunas na literatura a serem pesquisadas de modo a relacionar a integração dos sistemas de gestão como meio para as organizações tornarem-se mais sustentáveis, auxiliando assim na elaboração de um modelo teórico e das hipóteses de pesquisa. Os resultados parciais obtidos ressaltam a lacuna na literatura de estudos nessa área, principalmente que contemplem a dimensão social do Triple Bottom Line. Lacunas na literatura foram identificadas também no que se refere à análise do impacto da adoção dessas abordagens normativas no desempenho organizacional. A segunda etapa da metodologia é composta por estudos de casos múltiplos em empresas de diferentes setores e que tenham implantado sistemas de gestão de maneira integrada. Os resultados obtidos mostram que a certificação auxilia no desenvolvimento de ações sustentáveis, resultando em impactos econômicos, ambientais e sociais positivos. Nesta etapa, testou-se o modelo e as hipóteses levantadas na abordagem bibliométrica. A terceira etapa da metodologia é composta por análises estatísticas de dados secundários extraídos da revista Exame ?Maiores e Melhores\'. Os dados do ano de 2014 das empresas foram tratados por meio do software MINITAB 17 ®. Por meio do teste de mediana de mood, as amostras foram testadas e apresentaram diferenças estatisticamente significativas para o desempenho das empresas em diferentes setores. De maneira geral, as empresas com SGI apresentam melhor desempenho econômico do que as demais. Com a mesma base de dados, utilizando o modelo de equações estruturais e o software Smart PLS 2.0, criou-se um diagrama de caminhos analisando os constructos (SGI) com variáveis de desempenho (Endividamento, Lucratividade, Patrimônio, Crescimento e Retorno). O modelo de equações estruturais testado apresentou força para a relação entre SGI com Endividamento, Lucratividade, Patrimônio e Crescimento. As diferentes metodologias apresentadas contribuíram para responder a hipótese e afirmar com base na amostra deste trabalho que o SGI leva as empresas a terem melhor desempenho econômico, ambiental e social (baseado no TBL). / The objective of this study is to analyze the impact of the integration of management systems (SGI) into organizational performance based on a Triple Bottom Line perspective in order to ascertain if this implementation contributes for the company to become more sustainable. The multi-method approach utilized was divided into three phases. Firstly, a systematic literature review was elaborated using a bibliometric approach as ISI Web of Knowledge (Web of Science) was the database selected. These analyzes suggest gaps to be researched in order to connect the management systems as a way to become more sustainable, thereby assisting in the development of a theoretical model and research hypotheses. Partial results highlight the gap in the research literature in this area, especially those related to the social dimension of the Triple Bottom Line. Literature gaps were also identified in regards to the impact of adopting these normative approaches to organizational performance. The second step of the methodology consists of multiple case studies in companies from different sectors which have implemented integrated standards. Findings show that certification helps developing sustainable actions, resulting in economic, environmental and social positive impacts. In this phase, a model and assumptions extracted from the bibliometric approach were tested. Lastly, the third phase of the methodology consists of secondary statistical data analysis. The database was extracted from Exame \'Maiores e Melhores\' magazine. Company data for the year of 2014 were processed using MINITAB 17® software. Using Mood\'s median test, the samples were tested and showed statistically significant differences in the performance of companies in different sectors. In general, companies with integrated management systems have had better economic performance compared to other companies. In addition, using the same database, a diagram path analyzing the constructs (SGI) with performance variables (Debt, Profitability, Equity, Growth and Return) was created using the structural equation model and software Smart PLS 2.0. The tested structural equation model showed strong links to the relationship between SGI with Debt, Profitability, Growth and Equity. The different methodologies hereby presented contributed to answer the hypothesis and to affirm that, based on the samples utilized in this work, SGI lead companies to have better economic, environmental and social performance (based on TBL).
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Assemblages of groundfish caught using commercial fishing strategies off the coasts of Oregon and Washington from 1985-1987Rogers, Jean Beyer 23 February 1994 (has links)
The groundfish trawl fishery operating off the coasts of Oregon
and Washington 1985-1987 caught six major assemblages of species
which could be treated as units in developing mixed-species
management plans. Eighty-one percent of the tows observed on
commercial vessels were consistently placed in one of the assemblage
designations using three multivariate techniques. Two of the
assemblages were dominated by a single species, pink shrimp (Pandalus
jordani) or widow rockfish (Sebastes entomelas). The other
assemblages identified were: a deepwater rockfish assemblage, a
deepwater Dover sole assemblage, a nearshore mixed-species
assemblage, and a bottom rockfish assemblage. The assemblage
designations of the consistently placed tows were predicted with an
estimated 85% average accuracy using discriminant functions based on
the gear used and bottom depth fished. Fishermen had different
targets (intended catch) for each assemblage caught. The mixed-species
assemblages had several targets, representing at least some
of the dominant species in the assemblage. Targeting and discarding
information indicated that fishermen did not always intend to catch
the species together; there were unintentional or unavoidable catches
of all the major species except for shrimp in the shrimp assemblage.
Discarding occurred in all the assemblages, primarily due to
unmarketable species or fish that were too small to market.
Monitoring the assemblages over time could be accomplished by using
the defined strategies with logbook data, particularly if the large
and small rockfish categories were used to consistently separate
shelf and deepwater rockfish. The defined strategies could not
effectively predict the research cruise assemblages or catches;
research data do not accurately describe commercial catches. / Graduation date: 1994
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Observational and Numerical Modeling Studies of Turbulence on the Texas-Louisiana Continental ShelfZhang, Zheng 16 December 2013 (has links)
Turbulent dynamics at two sites (C and D) in a hypoxic zone on the Texas- Louisiana continental shelf were studied by investigating turbulence quantities i.e. turbulence kinetic energy (TKE), dissipation rate of TKE (E), Reynolds stress (τ ), dissipation rate of temperature variance (χ), eddy diffusivity of temperature (ν't), and eddy diffusivity of density (ν'p). Numerical models were also applied to test their capability of simulating these turbulence quantities.
At site D, TKE, E, and τ were calculated from velocity measurements in the bot- tom boundary layer (BBL), using the Kolmogorov’s -5/3 law in the inertial subrange of energy spectra of vertical velocity fluctuations in each burst measurement. Four second-moment turbulence closure models were applied for turbulence simulations, and modeled turbulence quantities were found to be consistent with those observed. It was found from inter-model comparisons that models with the stability functions of Schumann and Gerz predicted higher values of turbulence quantities than those of Cheng in the mid layer, which might be due to that the former stability functions are not sensitive to buoyancy.
At site C, χ, E, v’t, and ν’p were calculated from profile measurements throughout the water column, and showed high turbulence level in the surface boundary layer and BBL, as well as in the mid layer where shear stress was induced by advected non-local water above a hypoxic layer. The relatively high dissolved oxygen in the non-local water resulted in upward and downward turbulent oxygen fluxes, and the bottom hypoxia will deform due to turbulence in 7.11 days. Two of the four models in the study at site D were implemented, and results showed that turbulence energy resulting from the non-local water was not well reproduced. We attribute this to the lack of high-resolution velocity measurements for simulations. Model results agreed with observations only for χ and E simulated from the model with the stability function of Cheng in the BBL. Discrepancies between model and observational results lead to the following conclusions: 1) the stability functions of Schumann and Gerz are too simple to represent the turbulent dynamics in stratified mid layers; 2) detailed velocity profiles measurements are required for models to accurately predict turbulence quantities. Missing such observations would result in underestimation,
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Modélisation des consommations d'énergie et des émissions de CO² à long terme appliquée au secteur résidentiel algérien / Modeling of long-term energy consumption and CO² emissions applied in algerian residential sectorOuahab, Athmane 06 July 2015 (has links)
Le secteur résidentiel en Algérie consomme 25 % de l'énergie finale et émet en moyenne 21 % des gaz à effet de serre. Or, il existe un important gisement d'économie d'énergie dans ce secteur. Ce constat a conduit à rechercher la manière de rendre le secteur du logement plus efficient en termes de consommation d'énergie et d'émission de CO2. Cette thèse vise à développer différentes méthodes d'analyse quantitative dédiées à l'amélioration performantielle du secteur résidentiel à l'horizon 2050 . Il s'agit, en clair, d'infléchir les consommations d'énergie et de stabiliser les émissions de CO2. La comparaison entre la France et l'Algérie doit mettre de mettre en lumière les différences, tant dans les dynamiques des structures de parcs que dans celles induites par les différentiels climatiques.Ce travail s'inscrit dans une démarche prospective. Il s'appuie sur les principes de l'exercice prospectif développés par Jacques Arcade et Michel Godet, et il s'inspire pleinement de nombreux travaux de recherche (ETHEL, CLIP…). Il a pour ambition de développer un modèle de prospective énergétique bottom-up, capable de mesurer différentes trajectoires de l'évolution des consommations d'énergie dans le secteur résidentiel et les émissions qui en découleraient à l'horizon 2050.Ce modèle s'articule à partir des données du scénario central de la démographie et du parc de logements de l'Office national des statistiques algérien, ainsi que les hypothèses argumentées relatives aux évolutions démographiques des ménages. La poursuite des tendances actuelles, en termes de consommations d'énergie et d'émissions à l'horizon 2050, permet de tracer un scénario de référence sur lequel la thèse s'appuie pour identifier les actions à mettre en œuvre afin d'y apporter d'éventuelles solutions. En se basant en effet sur un ensemble de leviers technologiques, notre modèle peut établir des scénarios volontaristes dans lesquels l'on suppose plusieurs trajectoires de l'évolution du couple consommations/émissions.Outre l'intérêt scientifique de ce travail, le développement de ce modèle peut constituer un outil d'aide à la mise en oeuvre d'une politique énergétique portant sur l'amélioration de l'efficacité énergétique dans le secteur du logement ; les scénarios réalisés peuvent en outre constituer une feuille de route pour de nouvelles stratégies énergétiques. / The residential sector in Algeria consumes 25 % of the final energy and emits about 21% of greenhouse gas emissions. However, there is a significant potential of energy saving in this sector. This leads to looking for ways to make the sector of housing more efficient in terms of energy consumption and CO2 emissions. This thesis aims to develop different methods of quantitative analysis dedicated to improving the performance of the résidential sector in 2050. In other words, the objective is to reduce energy consumption and stabilize CO2 emissions. The comparison between France and Algeria should help to clarify the differences in both dynamic structures housing stock as well as in those induced by climate differentials.This research work fits into a prospective approach. It is based on the principles of prospective exercise developed by Jacques Arcade, Michel Godet, and it is influenced by numerous research works (ETHEL, CLIP). It has the ambition to develop a model of bottom-up energy prospective capable of measuring various trajectories of the evolution of energy consumption in the residential sector and resulting emissions by 2050.This model is based on the data of the central scenario of demography and the housing stock of the Algerian National office of Statistics, and on the well-argued assumptions concerning the démographic evolution of households. The continuation of current trends in terms of energy consumption at the approach of 2050 allows us to draw up a reference scenario on which the thesis is based to identify the actions to be implemented to identify possible solutions. Indeed, by basing itself on a set of technological levers, our model can establish voluntaris scenarios in which several trajectories of the evolution of the consumption/emissions pair can be envisaged.Besides the scientific interest of this work, the developement of this model can establish a help tool for the implementation of an energy policy concerning the improvement of the energy efficiency in the sector of housing ; moreover, the scenarios undertaken could constitute a road map for new energy strategies.
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Développement d'une approche analytique non ciblée pour l'étude des protéines dans les milieux complexes, environnementaux et biologiques / Development of an untargeted analytical approach for the identification and quantification of proteins in complex biological and environmental matricesEddhif, Balkis 04 December 2017 (has links)
Grâce aux récents progrès en terme d'instrumentation analytique, la protéomique, en tant que science qui étudie le protéome d'un organisme ou d'un milieu, a connu un véritable tournant et a permis d'étendre le champ des connaissances sur le fonctionnement du vivant dans son ensemble (structure, fonction, métabolisme, dynamisme). Néanmoins, l'étude des protéomes représente un challenge pour de nombreux biologistes, chimistes et biochimistes, en raison notamment de la complexité des échantillons étudiés. De nombreux protocoles analytiques ont d'ores et déjà été développés. Cependant, dans leur ensemble, ces stratégies sont relativement longues et multi-étapes et le plus souvent ciblées sur une protéine donnée.Dans ce contexte, ce travail de thèse a pour objectif de simplifier les protocoles expérimentaux existants afin de limiter les pertes en protéines et ainsi amplifier leurs signaux au cours d'une analyse « Bottom-up » par LC-HRMS (analyse « hors gel »). Chaque étape du processus a été décortiquée et optimisée. Dans un premier temps, les paramètres UPLC-HRMS/MS ont été optimisés afin d'améliorer la détection et la quantification des protéines présentes à des concentrations très variables dans les milieux étudiés. Ensuite, une approche de purification simplifiée qui repose sur une seule et unique étape de lavage et solubilisation des protéines a été mise au point. La démonstration de son efficacité « chimique » et « biologique » a ensuite été réalisée via une étude mécanistique au cours de laquelle les changements de conformation des protéines ont été étudiés à chacune des étapes de purification proposées. Enfin, certains paramètres influençant l'extraction des protéines à partir de ces mêmes matrices ont été étudiés afin de proposer à terme un protocole d'extraction à la carte compatible avec une analyse directe par LC-HRMS/MS. / Recent advances in proteomics have been spurred by the rapid development of hybrid and/or high-resolution mass analysers (HRMS/MS). These powerful instrumentations have led to significant improvements in « Bottom-up » approach and have enabled to deepen our knowledge on the functionality of biological systems (structure, function, metabolism, dynamic, etc).Despite their high sensibilities, the potential of such instruments could be significantly lessened by an imperfect sample pre-treatment. In this context, current sample pretreatments follow multi-steps experimental workflows, which alternatively lead to low recoveries of proteins. In this line, this study aims at developing a simple and versatile strategy in order to reduce protein losses and enhance their detection in gel-free LC-MS analysis. First, an analytical method based on liquid chromatography and tandem mass spectrometry was developed to detect and quantify complex peptides mixture. Secondly, a universal, simple and fast purification approach was designed with the aim to purify protein extracts in only one-step. For this purpose, the molecular reactivity, dynamics and conformational changes of proteins at each development step were comprehensively investigated with a set of spectroscopic techniques, in order to select the best strategy. Finally, different factors influencing extraction of proteins were investigated with the goal in the long term to propose an on-demand extraction protocol for direct analysis of proteins by LC-HRMS/MS.
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INCERTEZA DE MEDIÇÃO EM ANÁLISES MICOTOXICOLÓGICAS: ESTIMATIVA PELAS ABORDAGENS BOTTOM UP, MONTE CARLO E KRAGTEN / MEASUREMENT UNCERTAINTY IN MYCOTOXINS ANALYSIS: EVALUATION BY BOTTOM UP, MONTE CARLO AND KRAGTEN APPROACHESWovst, Liziane Rachel da Silva 06 March 2015 (has links)
Different approaches for the estimation of the uncertainty related to measurement results are found in the literature and in published guidelines. In the present work three approaches were used to estimate the uncertainty of the determination of aflatoxins (AB1, AB2, AG1, AG2) and deoxynivalenol in maize by liquid chromatography coupled to mass spectrometry tandem (LC-MS/MS): the Bottom up approach, adapted from the Guide to the Expression of Uncertainty in Measurement (ISO GUM); the Monte Carlo Method (MCM), which propagates distributions assigned to the input quantities through a numerical simulation; and the Kragten approach wich calculates standard deviations and confidence intervals with a universally applicable spreadsheet technique. A measurement equation was developed for mycotoxins analysis and a cause-and-effect diagram was draft to assist in the identification of the sources of uncertainty associated with the method. Detailed analysis of contributions of the various uncertainty sources was carried out. Measurement uncertainty was determined by the addition of the variances of the individual steps of the test procedure, according to each approach employed. The Bottom up, MCM and Kragten approaches produced very similar estimates to the combined uncertainty and the coefficient of variation (CV) between them was smaller than 1.0%. The main contribution to overall uncertainty is the intermediate precision with contributions over 90,0% for each mycotoxin. The results obtained with this research conclude that the three approaches are adequate for estimating the uncertainty in mycotoxin assays with LC-MS/MS technique. Among them, Bottom up is the most appropriate approach, since it requires that the analyst performs a detailed investigation about dominant components of the measurement uncertainty, allowing for better understanding and improvement of the measurement process. The Monte Carlo and Kragten methods are indicated the data generated by the Bottom up approach. / A literatura cita diferentes abordagens para estimar a incerteza de medição em ensaios quantitativos. No presente trabalho três abordagens foram utilizadas para estimar a incerteza da determinação de aflatoxinas (AB1, AB2, AG1, AG2) e desoxinivalenol em milho por cromatografia líquida acoplada à espectrometria de massa tandem (LC-MS/MS): a abordagem Bottom up, adaptada do Guia para a Expressão da Incerteza de Medição (ISO GUM); o método de Monte Carlo (MMC), que propaga distribuições atribuídas às grandezas de entrada através de uma simulação numérica; e a abordagem de Kragten que calcula desvios padrão e intervalos de confiança com uma técnica planilha universalmente aplicável. Um modelo matemático foi desenvolvido para os ensaios de micotoxinas e um diagrama de causa-efeito foi proposto para auxiliar na identificação das fontes de incerteza associadas ao método.
A análise detalhada das contribuições das várias fontes de incerteza foi realizada. A incerteza de medição foi determinada pela adição das variações dos passos individuais do procedimento de ensaio, de acordo com cada abordagem. Os métodos Bottom up, MMC e Kragten geraram estimativas similares para a incerteza combinada, com um coeficiente de variação (CV) menor que 1,0% entre elas. O principal componente de incerteza é a precisão intermediária, com contribuições acima de 90,0% para cada micotoxina. Como resultado da pesquisa, conclui-se que as três abordagens são adequadas para estimar a incerteza nos ensaios para quantificação de micotoxinas por LC-MS/MS. Dentre elas, a abordagem Bottom up é a mais apropriada, pois requer que o analista avalie o método detalhadamente para identificar os principais componentes de incerteza, possibilitando a implementação de melhorias no sistema de medição. Os métodos de Monte Carlo e Kragten são indicados como uma ferramenta de confirmação dos resultados obtidos pela abordagem Bottom up.
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Sustentabilidade em gestão de projetos e sua relação com sucesso em projetos: proposição de um modelo teórico e empírico. / Sustainability in project management and its relationship with sucess in projects: proposal of a theoretical and empirical model.Mauro Luiz Martens 22 May 2015 (has links)
Este trabalho trata dos temas sustentabilidade, gestão de projetos e sucesso em projetos. Por abordá-los de forma conjunta, preenche uma lacuna de pesquisa que trata da conexão entre os três temas. O objetivo da tese, desenvolvida por artigos, é propor um modelo teórico e empírico de sustentabilidade aplicável no contexto de gestão de projetos e orientado para o sucesso em projetos. Como metodologia fez-se uso da abordagem combinada, envolvendo pesquisa qualitativa e quantitativa com aplicação de multi métodos. A pesquisa qualitativa foi utilizada para a sistematização da literatura dos temas chaves e para o desenvolvimento de estudos de casos múltiplos com aplicação de entrevistas com gestores de projetos e de sustentabilidade, bem como aplicação de questionário aos membros de equipes de projetos. A pesquisa quantitativa foi utilizada para a realização de levantamento survey, com 143 gestores de projetos em empresas brasileiras, e análise estatística por meio da modelagem de equações estruturais, bem como foi aplicado o método de análise fatorial exploratória. Os constructos e variáveis do modelo teórico proposto, bem como os protocolos de pesquisa survey, foram validados por meio de um fórum com 11 especialistas oriundos de 10 universidades, localizadas em seis países diferentes. Como contribuições deste estudo pode-se destacar a estruturação do referencial teórico de sustentabilidade em gestão de projetos e de sucesso em projetos; a apresentação e validação da estrutura de um modelo teórico e empírico de constructos e variáveis de sustentabilidade com enfoque Triple-Bottom Line - TBL (econômica, ambiental e social) em gestão de projetos orientado ao sucesso em projetos; e, a validação estatística do relacionamento entre sustentabilidade em gestão de projetos e sucesso em projetos. Esta última relação foi confirmada pela alta significância da relação causal entre os constructos, pois sustentabilidade em gestão de projetos contribui positivamente para o sucesso em projetos, explicando 43% dos efeitos sobre sucesso em projetos. Em decorrência, foram desenvolvidos seis artigos científicos, alguns publicados e outros submetidos para periódicos internacionais. / This research looks to study sustainability, Project management and project success. Merging these themes, this thesis works on a gap of research related to approaching both topics. For that matter, this study, developed by articles model, aims to propose a theoretical and empirical framework of sustainability, applicable into project management context and oriented to project success. The combined approach was used as methodology, engaging qualitative and quantitative research by applying multi methods. Qualitative research was used to systematize the literature of key themes and to develop multiple case studies by applying semi-structured interviews with people responsible for projects and sustainability areas and questionnaire application to projects team members. Quantitative research was used to develop a survey involving 143 project managers in Brazilian companies. Statistics analysis was carried out in order to treat the data through structural equation modeling. Exploratory factor analysis was also used. Constructs and variables of the conceptual framework proposed, as well as the survey research protocols, were validated by experts through and expert panel of eleven experts from ten universities and six different countries. Contributions of this study may highlight the development of the bibliographic review of sustainability in project management and project success topics; the presentation and validation of the conceptual and empirical model of constructs and variables of sustainability (with triple-bottom line perspective) in project management oriented to project success; and the statistical validation of the relationship between sustainability in project management and project success. This relationship was confirmed by the high significance of the casual relation between both constructs, explaining that the constructs of sustainability in project management contributes positively to obtain project success. It was found that 43% of these constructs affect project success. At the end, six scientific articles were developed, and some of them were already published and others submitted to international journals.
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Hållbarhetsredovisning i kommuner : En studie som jämför kommuner i Västra Götaland / Sustainability reporting in municipalities : A comparative study of municipalities in Västra GötalandAvdic, Adna, Brodd, Andreas January 2018 (has links)
Idag arbetar allt fler företag och organisationer utifrån CSR-aktiviteter eftersom det är någonting allmänheten kräver mer och mer, att företag och organisationer ska ta hänsyn till miljön och samhället. Kommunala verksamheter skiljer sig ifrån företag och har ingen tvingande lag om att upprätta en hållbarhetsrapport. Eftersom att hållbarhetsrapporterna är mer tillämpbara på företag blir det svårt för kommunala verksamheter att införa detta. De kommunala verksamheterna har olika intressentgrupper att beakta där de två viktigaste är politiker och invånare. På grund av att det råder informationsasymmetri mellan kommuner och dess intressenter har de skyldighet att ge ut information för att minska denna. Studien syftar till att göra en undersökning av kommuner i Västra Götaland för att se hur de arbetar med hållbarhetsredovisning och om de enbart redovisar den ekonomiska aspekten eller även den miljömässiga och den sociala utifrån Tripel Bottom Line. Syftet är också att se till vilka intressenter hållbarhetsredovisningen riktar sig till men även att bidra med en större förståelse för hållbarhetsredovisning i kommunal verksamhet. Genomförandet av studien har gjorts genom kvalitativa interjuver där sex kommuner har intervjuats och sammanlagt nio informanter har bidragit med information för att besvara studiens syfte. Det inhämtade empiriska materialet har mynnat ut i en analys som är i relation till den teoretiska referensramen som i sin tur har lett fram till slutsatsen. Studien har kommit fram till att kommuner gör lite olika när de följer upp och analyserar sina resultat men att de alla utgår ifrån de social, miljömässiga och ekonomiska dimensionerna. Det förekommer dock svårigheter när kommuner skall analysera sina nyckeltal för att se vad exempelvis ökad sjukfrånvaro beror på då det inte finns ett generellt tillvägagångsätt för kommuner att använda sig av. Studien har även kommit fram till att en kommun har en mängd olika intressenter men att dessa intressenter värderas olika. / Today, more and more companies and organizations are working on CSR activities because it is something the public demands more and more that companies and organizations should take environmental and community considerations into account. Municipal operations differ from companies and have no compulsory law to establish a sustainability report. Because sustainability reports are more applicable to companies, it will be difficult for municipalities to introduce this. The municipalities have different interest groups to consider where the two most important are politicians and residents. Due to the existence of information asymmetry between municipalities and their stakeholders, they have an obligation to provide information to reduce this. The study aims to investigate municipalities in Västra Götaland to see how they work with sustainability reporting and whether they only report the economic aspect or the environmental and social aspects of Tripel Bottom Line. The aim is also to look at which stakeholders the sustainability report is aimed at, but also to contribute to a greater understanding of sustainability reporting in municipal operations. The implementation of the study has been done through qualitative interviews where six municipalities have been interviewed and a total of nine informants have contributed with information to answer the purpose of the study. The obtained empirical material has come up with an analysis that is in relation to the theoretical frame of reference, which in turn has led to the conclusion.The study has concluded that municipalities act differently when they follow up and analyze their results, but that they are all based on the social, environmental and economic dimensions. However, there are difficulties when municipalities are to analyze their key figures to see, for example, increased sickness absence due to the absence of a general approach for municipalities to use. The study also found that a municipality has a wide range of stakeholders but that these stakeholders are valued differently.
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