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Zpracování klimatologických měření z experimentálních lokalit v Kyrgyzstánu a jejich synopticko-klimatologická interpretace / The Processing of Climatologic Records from Experimental Locations in Kyrgyzstan and the Synoptic-climatologic Interpretation ThereofSýkorová, Petra January 2016 (has links)
The Charles University Faculty of Science KFGG team took part in an intensive research in the area of Kyrgyz glacial lakes. The collecting of records from three meteorological stations in the locations of Kolor (2,700 m above sea level) and Adygine (3,500 and 3,800 meters above sea level) was part of the research. The aim of this thesis was to analyze the homogeneity of climatic data measured in experimental locations using the SNHT method (Standard Normal Homogeneity Test), process the data using general climatological processes, create a classification of circulation types for the area of interest using Jenkinson's and Collinson's method, and finally, to quantify the relationships between individual circulation types and the values of chosen climatic elements. The analysis results are homogenized climatic sets for the Adygine H station (3,800 m above sea level) and a summary of basic statistics and trends of climatic elements in the area. Furthermore, a catalogue of circulation types was created for the period from August 2007 to July 2011, and finally, the relationships between individual circulation types and manifestations of climate elements (air temperature, precipitation and global radiation). The results of this thesis may be used to identify the types connected with bursts of glacial...
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Crescimento e caracterização de soluções sólidas óxidas. / Growth and caracterization of the oxides solid solutions.Andreeta, Jose Pedro 26 September 1984 (has links)
Experimentos sistemáticos de crescimento de cristais pelo método de soluções sólidas óxidas de GdAlO3:Cr3+ (estrutura pseudo perovskita), foram efetuados em diversas composições de solventes. Os perfis de concentrações dopante (Cr3+) e do solvente (Pb),em amostras previamente selecionadas e os coeficientes de segregação efetivos foram determinados e comparados com os dos cristais crescidos pelo método Czochralski. Modelos teóricos foram desenvolvidos para o entendimento dos resultados experimentais e outros são propostos com o objetivo de fornecer tratamentos alternativos para os efeitos dos parâmetros de crescimento tais como: flutuações térmicas, forma geométrica nucleações secundárias, evaporação do dopante, reações químicas e estabilidade de crescimento na homogeneidade das soluções sólidas. Devido ao interesse científico-tecnológico também foram crescidos outros cristais de estrutura perovskita como GdAlO3:La3+, LaAlO3:Cr3+ e NdAlO3:La3+ pelo método de fluxo e GdAlO3:Cr3+:La3+, pelo método Czocharalski e os resultados das experiências de crescimento estão descritas neste trabalho. / Systematic growth experiments by flux method of the oxides solid solutions of GdAlO3:Cr3+ (perovskite type) were done with several solvents compositions. The doping (Cr3+) and solvent (Pb) concentrations profiles in selected samples, and the effetive segregations coefficient were determined and compared with those obtained by Czochralski method. Theoretical models for crystal growth process were developed to understand the experimental results, and others are proposed to give alternative treatment on several growing parameters like thermal fluctuations, geometric crystal shape, secondary nucleations, doping evaporations, chemical reactions and growth stability effects in the solid solutions homogeneity. Due to scientific and technological interest, also were grown other perovskite crystals like GdAlO3:La3+, LaAlO3:Cr3+ and NdAlO3:La3+ by flux method and GdAlO3:Cr3+:La3+ by Czochralski method and the results are descrived in the present work.
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Otimização da análise por ativação neutrônica instrumental para o estudo de homogeneidade dentro do frasco de materiais de referência de origem marinha / Optimization of instrumental neutron activation analysis for the within-bottle homogeneity study of reference materials of marine originSilva, Daniel Pereira da 23 February 2017 (has links)
A utilização de materiais de referência tem sido crescente em laboratórios químicos, uma vez que são importantes para a validação de métodos analíticos. Tais materiais são em geral importados, o que demanda altos investimentos financeiros para adquiri-los, e, portanto, impacta na não utilização dos mesmos por muitos laboratórios nacionais. A certificação de um material de referência é um processo complexo que pressupõe oferecer ao usuário valores atribuídos às propriedades de interesses no material. Neste processo, deve ser realizada a verificação da homogeneidade do material nos frascos. No presente estudo, foi realizado o estudo de homogeneidade dentro do frasco para os elementos K, Mg, Mn, Na e V em dois materiais de referência certificados de origem marinha: o material de referência de mexilhão, produzido no Laboratório de Ativação Neutrônica (LAN) do IPEN - CNEN/SP e o material de referência de tecido de ostra produzido no exterior. Para tanto, os elementos foram determinados por Análise por Ativação Neutrônica Instrumental, com massas variando entre 1 e 250 mg e estimou-se a massa mínima que variou de 0,015 g para Na no material de referência de mexilhão a 0,100 g para V nos dois materiais de referência. / The use of reference materials has been increasing in chemical analysis laboratories as its use is important for measurement validation in analytical chemistry. Such materials are generally imported, which require high financial investments in order to acquire them, and therefore it impacts on the difficulty to many national laboratories to use reference materials in their chemical analysis routine. Certification of reference materials is a complex process that assumes that the user is given appropriate assigned values of the properties of interests in the material. In this process, the homogeneity of the material must be checked. In this study, the within-bottle homogeneity study for the elements K, Mg, Mn, Na and V was performed for two reference materials of marine origin: the mussel reference material produced at the Neutron Activation Laboratory (LAN) of IPEN - CNEN/SP and an oyster tissue reference material produced abroad. For this purpose, the elements were determined in subsamples with masses varying between 1 and 250 mg by Instrumental Neutron Activation Analysis (INAA) and minimum sample intakes were estimated, ranging from 0.015 g for Na in the mussel reference material to 0.100 g for V in the two reference materials.
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Otimização da análise por ativação neutrônica instrumental para o estudo de homogeneidade dentro do frasco de materiais de referência de origem marinha / Optimization of instrumental neutron activation analysis for the within-bottle homogeneity study of reference materials of marine originDaniel Pereira da Silva 23 February 2017 (has links)
A utilização de materiais de referência tem sido crescente em laboratórios químicos, uma vez que são importantes para a validação de métodos analíticos. Tais materiais são em geral importados, o que demanda altos investimentos financeiros para adquiri-los, e, portanto, impacta na não utilização dos mesmos por muitos laboratórios nacionais. A certificação de um material de referência é um processo complexo que pressupõe oferecer ao usuário valores atribuídos às propriedades de interesses no material. Neste processo, deve ser realizada a verificação da homogeneidade do material nos frascos. No presente estudo, foi realizado o estudo de homogeneidade dentro do frasco para os elementos K, Mg, Mn, Na e V em dois materiais de referência certificados de origem marinha: o material de referência de mexilhão, produzido no Laboratório de Ativação Neutrônica (LAN) do IPEN - CNEN/SP e o material de referência de tecido de ostra produzido no exterior. Para tanto, os elementos foram determinados por Análise por Ativação Neutrônica Instrumental, com massas variando entre 1 e 250 mg e estimou-se a massa mínima que variou de 0,015 g para Na no material de referência de mexilhão a 0,100 g para V nos dois materiais de referência. / The use of reference materials has been increasing in chemical analysis laboratories as its use is important for measurement validation in analytical chemistry. Such materials are generally imported, which require high financial investments in order to acquire them, and therefore it impacts on the difficulty to many national laboratories to use reference materials in their chemical analysis routine. Certification of reference materials is a complex process that assumes that the user is given appropriate assigned values of the properties of interests in the material. In this process, the homogeneity of the material must be checked. In this study, the within-bottle homogeneity study for the elements K, Mg, Mn, Na and V was performed for two reference materials of marine origin: the mussel reference material produced at the Neutron Activation Laboratory (LAN) of IPEN - CNEN/SP and an oyster tissue reference material produced abroad. For this purpose, the elements were determined in subsamples with masses varying between 1 and 250 mg by Instrumental Neutron Activation Analysis (INAA) and minimum sample intakes were estimated, ranging from 0.015 g for Na in the mussel reference material to 0.100 g for V in the two reference materials.
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Determinação quantitativa da homogeneidade da distribuição de urânio em combustiveis nucleares tipo placa / Quantitative determination of uranium distribution homogeneity in MTR fuel type platesFerrufino, Felipe Bonito Jaldin 03 May 2011 (has links)
O IPEN-CNEN/SP produz o combustível para suprir o seu reator nuclear de pesquisas IEA-R1. O combustível é montado a partir de placas combustíveis contendo um núcleo do compósito U3Si2-Al. Uma boa homogeneidade na distribuição de urânio no núcleo da placa combustível é essencial, pois garante um bom desempenho sob irradiação. Considerando a baixa potência do reator IEA-R1, atualmente, a distribuição de urânio na placa combustível é avaliada apenas por meio de inspeção visual de radiografias. Contudo, tendo em vista a possibilidade do IPEN fabricar o combustível para o novo Reator Multipropósito Brasileiro (RMB), que terá potência elevada, tornou-se inadiável o desenvolvimento de uma metodologia para determinar quantitativamente a homogeneidade da distribuição de urânio no combustível. Este trabalho apresenta uma metodologia baseada na atenuação de raios X para quantificar a distribuição da concentração de urânio no núcleo da placa combustível, por meio da análise da densidade óptica de radiografias e comparação com padrões. Os resultados demonstraram a não aplicabilidade do método, considerando a especificação atual para as placas combustíveis, devido ao alto valor do erro intrínseco ao método. Contudo, o estudo dos erros envolvidos na metodologia, buscando aumentar a sua exatidão e precisão, pode viabilizar a aplicação do método para qualificar o produto final. / IPEN/CNEN-SP produces the fuel to supply its nuclear research reactor IEA-R1. The fuel is assembled with fuel plates containing an U3Si2-Al composite meat. A good homogeneity in the uranium distribution inside the fuel plate meat is important from the standpoint of irradiation performance. Considering the lower power of reactor IEA-R1, the uranium distribution in the fuel plate has been evaluated only by visual inspection of radiographs. However, with the possibility of IPEN to manufacture the fuel for the new Brazilian Multipurpose Reactor (RMB), with higher power, it urges to develop a methodology to determine quantitatively the uranium distribution into the fuel. This paper presents a methodology based on X-ray attenuation, in order to quantify the uranium concentration distribution in the meat of the fuel plate by using optical densities in radiographs and comparison with standards. The results demonstrated the inapplicability of the method, considering the current specification for the fuel plates due to the high intrinsic error to the method. However, the study of the errors involved in the methodology, seeking to increase their accuracy and precision, can enable the application of the method to qualify the final product.
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Color Lines, and Regions and Their Stereo Matching / Lignes et régions couleurs et leur appariement stéréoLertchuwongsa, Noppon 13 December 2011 (has links)
En vision par ordinateur, les points saillants sont des caractéristiques essentielles aux algorithmes. Les performances dépendent de paramètres extérieurs (ex. illumination). Les mesures de similarité sont centrales à la reconnaissance. Pour assurer l'efficacité de traitement, les caractéristiques extraites d'une image doivent être stables, et la mesure de similarité doit les distinguer parfaitement.Dans cette thèse, des caractéristiques conjointes géométrie/couleur sont étudiées : lignes de couleur et régions. Elles fondent la détection d'une troisième, la profondeur, qui sert en retour à évaluer leurs performanceLes lignes sont des extensions des classiques lignes de niveau: l'espace couleur 3-D est projeté sur un espace 1-D adapté pour résumer l'information chromatique là où elle est adéquate,Les régions exploitent classiquement la connexité image mais jointe à une compacité dans l'histogramme bidimensionnel issu du modèle dichromatique. L'homogénéité ainsi définie garantit une robustesse a priori aux variations d'éclairage en séparant la couleur de l'intensité et les couleurs entre elles.Cette homogénéité est exploitée selon 2 méthodes d'extraction d'ensembles compacts autour des modes de l'histogramme: extraction analytique des extrema locaux de couleur, extraction de ces mêmes extrema contrôlée par les régions correspondantes de l'image.Pour la profondeur, trois calculs de disparité stéréoscopique sont proposés et les performances comparées avec la réalité terrain:1. Appariement de lignes couleur avec une distance de Hausdorff revisitée.2. Exploitation de la forme des histogrammes de disparité par régions3.Coopération entre appariement de points et de régions. / In computer vision, salient points are essential features to algorithms. Performances depend on external parameters (e.g. illuminant). Similarity measures are central to recognition.To secure the processing efficiency, extracted features have to be stable enough, and the similarity measure needs to perfectly distinguish between them.In the thesis, joint geometrical and color features are studied: color lines and regions. They found the detection of a third one, range, that helps in turn to assess their goodness.Color lines are extensions of classical level lines: the 3 D color space is mapped onto a 1 D scale especially designed to retain the chromatic information where it is suitable.Regions require the usual image connectivity but in association with compactness in the bi-dimensional histogram stemming from the dichromatic model. The so-designed homogeneity is granting an a priori good robustness against illumination variations in separating the body colors and splitting color from intensity.The latter homogeneity gives raise to 2 methods for extracting compact sets around histogram modes: color first analysis (an analytic extraction of color local extrema) , and joint color/space analysis (same but controlled by the region growing).As for depth, 3 methods to compute the stereo disparity are proposed for their results to be confronted with the ground-truth:1. Color line matching based on a modified Hausdorff distance,2. Studying the shape of the disparity histogram between regions,3. Cooperation between pixel correlation and region matching.The robustness of the designed features is proved on several stereo pairs. Future work deals with improving efficacy and accuracy.
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Determinação quantitativa da homogeneidade da distribuição de urânio em combustiveis nucleares tipo placa / Quantitative determination of uranium distribution homogeneity in MTR fuel type platesFelipe Bonito Jaldin Ferrufino 03 May 2011 (has links)
O IPEN-CNEN/SP produz o combustível para suprir o seu reator nuclear de pesquisas IEA-R1. O combustível é montado a partir de placas combustíveis contendo um núcleo do compósito U3Si2-Al. Uma boa homogeneidade na distribuição de urânio no núcleo da placa combustível é essencial, pois garante um bom desempenho sob irradiação. Considerando a baixa potência do reator IEA-R1, atualmente, a distribuição de urânio na placa combustível é avaliada apenas por meio de inspeção visual de radiografias. Contudo, tendo em vista a possibilidade do IPEN fabricar o combustível para o novo Reator Multipropósito Brasileiro (RMB), que terá potência elevada, tornou-se inadiável o desenvolvimento de uma metodologia para determinar quantitativamente a homogeneidade da distribuição de urânio no combustível. Este trabalho apresenta uma metodologia baseada na atenuação de raios X para quantificar a distribuição da concentração de urânio no núcleo da placa combustível, por meio da análise da densidade óptica de radiografias e comparação com padrões. Os resultados demonstraram a não aplicabilidade do método, considerando a especificação atual para as placas combustíveis, devido ao alto valor do erro intrínseco ao método. Contudo, o estudo dos erros envolvidos na metodologia, buscando aumentar a sua exatidão e precisão, pode viabilizar a aplicação do método para qualificar o produto final. / IPEN/CNEN-SP produces the fuel to supply its nuclear research reactor IEA-R1. The fuel is assembled with fuel plates containing an U3Si2-Al composite meat. A good homogeneity in the uranium distribution inside the fuel plate meat is important from the standpoint of irradiation performance. Considering the lower power of reactor IEA-R1, the uranium distribution in the fuel plate has been evaluated only by visual inspection of radiographs. However, with the possibility of IPEN to manufacture the fuel for the new Brazilian Multipurpose Reactor (RMB), with higher power, it urges to develop a methodology to determine quantitatively the uranium distribution into the fuel. This paper presents a methodology based on X-ray attenuation, in order to quantify the uranium concentration distribution in the meat of the fuel plate by using optical densities in radiographs and comparison with standards. The results demonstrated the inapplicability of the method, considering the current specification for the fuel plates due to the high intrinsic error to the method. However, the study of the errors involved in the methodology, seeking to increase their accuracy and precision, can enable the application of the method to qualify the final product.
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Vem får arbeta med reklam? : En kvalitativ studie om skapandet och reproduktion av homogenitet i reklambranschenNigren, Rebecca, Risberg, Tina January 2018 (has links)
The purpose of this study is to investigate underlying factors that create and maintain homogeneity in the advertising industry, and how those who produce advertising relate to this. The study is based on an intersectional perspective in order to reach a deeper understanding of how inequality is created in the advertising industry. The study's empirical data has been collected based on six qualitative interviews with women who work at different advertising agencies in Stockholm. Our results show that high financial, social and cultural capital affects the work opportunities favourably, and contributes to the industry's homogeneity. The term habitus has been used to locate and create an understanding of how homogeneity is created and reproduced. Furthermore, current norms and values within the industry have been identified and have created an understanding for the appearance of the homogenity. The result also shows that the advertising as a product, and the informants' experiences of their own workplace are affected by the industry's homogeneity, which has led to the argumention for a greater diversity among the employees. Advertising has a position of power in today's consumer society where they have influence over people's self-identities, which has led to the argument for a greater diversity among employees would had been favorable for everyone in order to be to feel represented, but also that the homosocial reproduction where men currently possess positions with more power should be broken in order to create a more equal industry which in turn can be a step towards a more equal society. / Syftet med uppsatsen är att ta reda på vilka processer som samverkar i skapandet och upprätthållandet av homogenitet i reklambranschen, utifrån ett intersektionellt perspektiv. Studiens empiri har samlats in utifrån sex kvalitativa intervjuer med kvinnor som arbetar på olika reklambyråer i Stockholm. Vårt resultat visar på att det krävs ett högt ekonomiskt, kulturellt och socialt kapital för att få jobb inom branschen. Begreppet habitus har används för att lokalisera och skapa en förståelse kring hur homogenitet skapas och reproduceras. I uppsatsen har det också identifierats att de olika könen befinner sig inom olika makt- och möjlighetsstrukturer inom branschen, vilket bland annat förklarats utifrån homosocial reproduktion. Resultatet visar att reklamprodukten och informanternas upplevelser av den egna arbetsplatsen påverkas av branschens homogenitet. Uppsatsen har skapat en insikt om att reklamskaparna har en maktposition i dagens konsumtionssamhälle där de besitter inflytande över människors självidentiteter. Därmed har det argumenterats för att det krävs en större mångfald bland de anställda för att bekämpa stereotypiserad reklam och låta alla känna sig representerade. Det har också framkommit att den homosociala reproduktionen där män i dagsläget besitter positioner med mer makt behövs brytas för att skapa en mer jämställd bransch som i sin tur kan vara ett steg mot ett mer jämställt samhälle.
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Development and validation of a method for separation of pregabalin and gabapentin capsules using Near Infrared hyperspectral imagingPersson, Emelie January 2019 (has links)
Seizures containing large numbers of units of narcotics, goods dangerous to health and doping are often sent to the Swedish National Forensic Centre (NFC). Only a fraction of these capsules or tablets can be analyzed, therefore the samples need to represent the whole seizure. If the samples show content variations, Near Infrared (NIR) spectroscopy in combination with hyperspectral imaging has been shown to be a promising tool to gauge the homogeneity in the seizures based on chemical content. The objective of this thesis was to further develop and then validate a method for the separation of pregabalin and gabapentin capsules using NIR hyperspectral imaging and Principal Component Analysis (PCA). Capsules containing different amounts of pregabalin and gabapentin were prepared and analyzed. Additionally, authentic seizures were analyzed to confirm that the method fulfilled its purpose. The result of this study showed that use of hyperspectral data in the wavelength range 1650-1750 nm gave the best differentiation between pregabalin and gabapentin capsules. Capsules containing the ratio 70-30 % gabapentin and pregabalin could be separated distinctively from capsules containing pure gabapentin. Multiple authentic seizures could be separated into groups correctly depending on the capsules or tablets content.
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L'effet bénéfique de l'augmentation de la variabilité perçue sur la réduction des préjugés et de la discriminationEr-Rafiy, Abdelatif 08 November 2010 (has links)
Nous examinons si l'augmentation de la variabilité perçue dans un groupe peut réduire les préjugés et la discrimination à l'égard de ses membres. Dans une série de 16 expériences en laboratoire et sur le terrain, nous avons d'abord attiré l'attention des participants soit sur l'homogénéité soit sur l'hétérogénéité des membres de ce groupe, et ensuite nous avons mesuré les attitudes ou les comportements. La variabilité perçue a été manipulée de différentes manières (en mentionnant ou non l'existence de plusieurs sous-groupes à l'intérieur du groupe cible, ou en montrant que les membres de l'exogroupe ont des opinions variées ou des caractéristiques différentes, ou en demandant aux participants de penser aux différences au sein des membres du groupe en question). Les préjugés et la discrimination ont été mesurés à l'aide d'échelles d’auto-évaluation, par la distribution de ressources, par le comportement d'aide d'un membre de l'exogroupe, ou encore par l'évaluation d'un candidat de l'exogroupe dans une situation de simulation de recrutement. Dans toutes les expériences, la variabilité perçue a réduit les préjugés et la discrimination. Cet effet pourrait être dû au fait que la variabilité perçue réduirait le rôle du groupe d'appartenance de la cible dans la production des attitudes et des comportements à l'égard des individus / We examined whether increasing individuals' perceived variability of an out-group reduces prejudice and discrimination toward its members. In a series of 16 laboratory and field experiments, we attracted participants' attention to either the homogeneity or the heterogeneity of members of an out-group, and then measured their attitudes or behaviors. Perceived variability was manipulated by making subgroups salient, by portraying the out-group members as having diverse opinions, by making salient that out-group members have different characteristics, or by asking participants to think about differences among out-group members. Prejudice and discrimination were measured in terms of self-reported attitudes, distribution of rewards, helping an out-group confederate, and evaluation of an out-group candidate in a simulated hiring decision. In all experiments, perceived variability decreased prejudice and discrimination. This effect may be due to the fact that perceived variability decreases the role of group membership in the production of attitudes and behaviors toward other individuals
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