Thèses : « Observer studies »

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Lopetegui, Lazo Marcelo A. « Inter-Observer Reliability Assessments in Continuous Observation Time Motion Studies ». The Ohio State University, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=osu1397236246.

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Warren, Lucy M. « Simulation of calcification clusters in observer performance studies for optimisation of digital mammography ». Thesis, University of Surrey, 2013. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.616916.

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Breast cancer is the most common cancer in women in the UK. Breast screening using mammography imaging is pelformed to detect cancers early and reduce the death rate from breast cancer. It is important that the effect of new imaging technologies on cancer detection is known prior to their use in breast screening. Clinical trials can measure this, however these are expensive and time consuming. In comparison, observer studies with simulated cancers can be performed in a fraction of the time. This thesis focuses on the simulation of calcification clusters and their use in observer studies. Once inserted into breast images the simulated calcification clusters have been shown to look realistic and have the correct contrast and sharpness. " The calcification clusters have been used in observer studies to compare two different types of digital detector - computed radiography (CR) and direct digital (DR) systems, different dose levels and different image processing algorithms. Calcification detection is significantly poorer when using a CR system compared with a DR system, and also sensitive to dose used. It has also been shown that image processing has a significant impact on calcification detection. However, this difference in calcification detection is smaller than the difference in calcification detection due to differences in detector type or dose. Image processing was not found to significantly impact detection of non-calcification cancers. The calcification detection measured using observer studies was compared to the threshold gold thicknesses measured with the CDMAM phantom. Threshold gold thickness was found to be relevant to calcification detection, however the acceptable and achievable threshold limits set in the European quality control protocol using this phantom need revising. The results of this work are important, providing evidence that can be used when selecting the optimal digital detector, dose and image processing.

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Cassigneul, Adèle. « Voir, observer, penser : Virginia Woolf et la photo-cinématographie ». Thesis, Toulouse 2, 2014. http://www.theses.fr/2014TOU20048.

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Partant de l'influence de la photographie victorienne de Julia Margaret Cameron, de la photographie et du cinéma d'avant-garde des années 1920 et de la production photographique de Virginia Woolf elle-même (albums de Monk's House), cette étude pose l'hypothèse que l'écriture de Virginia Woolf s'en inspire pour devenir à la fois photographique et cinématographique, photo-cinématographique. Explorant le texte comme dispositif complexe, nous analysons la plasticité de sa prose à travers motifs et stratégies de représentation afin de voir dans quelle mesure photographie et cinéma réforment et reforment le texte woolfien, dans ses modalités formelles et esthétiques, ainsi que dans sa portée éthique et politique. Après avoir replacé l'œuvre dans son contexte moderniste et souligné l'importance du rôle joué par la Hogarth Press, qui permet à l'écrivaine d'intégrer des images en texte, nous mettons en évidence le cinématisme de ses œuvres à travers l'exploration photo-filmique de la ville moderne et la structuration en montage du flux de conscience. Nous considérons ensuite le battement anachronique des fluctuations temporelles qui structurent l'œuvre dans ses phénomènes mémoriels de hantise et de survivance, l'image faisant retour en texte dans une durée contractée (instantané) ou dilatée (défilé d'images), à la fois personnelle et intime, collective et historique. Nous envisageons enfin le texte comme un espace de négociation subversif où l'image permet à l'auteure de prendre position "poéthiquement", alors que sont mis en scène des personnages atypiques à l'identité inassignable
This study contends that Virginia Woolf's writing draws its inspiration from Julia Margaret Cameron's Victorian photographs, the 1920s avant-garde photography and cinema, and Woolf's own Monk's House Albums, making her work at once photographic and cinematographic, or photo-cinematographic. Exploring the Woolfian text as a complex representation device, I examine the plasticity of its prose and narrative strategies to show how photography and cinema help to shape its aesthetic, but also ethical and political contents. This thesis first places Woolf's works in their modernist context and underlines the part played by the Hogarth Press, enabling Woolf to include images in her texts. I then shed light on the kinematic aspect of her work by analysing the photo-filmic exploration of the London scene and the montage of stream of consciousness. The third part probes into the anachronic rhythm of fluctuating time, emphasising the haunting aspects of memory through surviving images that condense their temporality in the instant (snapshot) or unroll it (streaming images) ; thus time achieves a personal and intimate, but also collective and historical dimension. Finally, I look at the Woolfian text as a subversive place of negotiation inhabited by eccentric characters with elusive identities and in which images help the author to make a "poethical" stand

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Nelson, Jennifer Clark. « A graphical methodology for describing interrater variability in ordinal assessments among many raters / ». Thesis, Connect to this title online ; UW restricted, 1999. http://hdl.handle.net/1773/9560.

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Shea, Kerry A. « Evaluation of a Computer-Based Observer-Effect Training on Mothers' Vocal Imitation of Their Infant ». DigitalCommons@USU, 2019. https://digitalcommons.usu.edu/etd/7694.

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Infants begin to learn important skills, such as contingency learning, social referencing, and joint attention through everyday interactions with their environment. When infants learn that their behavior produces a change in the environment (e.g., attention from others), infants engage in behavior that produces that effect (e.g., increases in smiling sustained engagement. When mothers and other caregivers respond immediately to infant behavior, they help their infant learn that the infant’s own behavior is effective, producing a change in the environment. The current investigation evaluated the effect of a computer-based training that aimed at teaching mothers to play a vocal-imitation contingency-learning game. The training included observer-effect methodology, meaning the mothers engaged in observation and evaluation of other mothers engaging in vocal imitation but did not themselves receive any direct coaching or feedback. All mothers completed the training during one session and in less than 45 min. Results indicate that all mothers increased their use of vocal imitation post training and maintained their performance at a two-week follow-up. Results are discussed in terms of how computer training may facilitate dissemination of responsive caregiver training.

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Schonwetter, Sara Wendi. « An Evaluation of Reactivity to Observer Presence While Self-Monitoring to Improve Swimming Performance ». Scholar Commons, 2012. http://scholarcommons.usf.edu/etd/4221.

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The current study evaluated the effects of self-monitoring by swimmers to improve their performance at practice and assessed the effects of reactivity to observer presence on their performance. Additionally, it investigated the accuracy of the swimmers' self-reports. Seven public high school swim team members used program boards to self-monitor in order to increase the number of assigned laps completed at practice. Reactivity to observer presence was assessed by having a confederate record the number of laps completed during observer absent conditions. A series of AB replications and an ABAB reversal design were used. The percentage of assigned laps completed increased during the self-monitoring phases. The self-monitoring and feedback phase showed an additional increase in the percentage of assigned laps completed, and also showed an increase in the mean level of reporting accuracy by the participants. The effects from the reactivity assessment were mixed; the percentage of assigned laps completed was lower on days that the observer was absent compared to the days the observer is present for only some of the participants. More research is needed to examine reactivity effects in sport settings.

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Kim, Jae-Seung. « Objective image quality assessment for positron emission tomography : planar (2D) and volumetric (3D) human and model observer studies / ». Thesis, Connect to this title online ; UW restricted, 2003. http://hdl.handle.net/1773/5836.

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Williams, Gethin. « Corporate planning in a turbulent environment : a participant observer longitudinal study of the introduction and operation of corporate planning in a college of higher education, 1974-84 ». Thesis, University of Bath, 1987. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.364060.

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Rashid, Mahbub. « On the configurational studies of building plans from the viewpoint of a situated observer : a partial theory of configuration for plans not involving curves ». Diss., Georgia Institute of Technology, 1998. http://hdl.handle.net/1853/23373.

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Sahu, Amit K. « Objective assessment of image quality (OAIQ) in fluorescence-enhanced optical imaging ». [College Station, Tex. : Texas A&M University, 2006. http://hdl.handle.net/1969.1/ETD-TAMU-1068.

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Stroud, Cynthia. « Stage Hypnosis in the Shadow of Svengali : Historical Influences, Public Perceptions, and Contemporary Practices ». Bowling Green State University / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1363090445.

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Rakov, Artem. « Unfolding the Assemblage : Towards an Archaeology of 3D Systems ». Thesis, Stockholms universitet, Filmvetenskap, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-182425.

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Recent scholarship around the topic of 3D mainly deals with the visual developments that have occurred in the medium during the 21st century. A common perception in these strands of research is that in comparison to the production workflows employed in the analogue era, the 3D compositions that are being crafted through the aid of the ever-evolving digital technology have made 3D develop for the better. Yet a question that nevertheless remains is how the technology itself employed to craft these compositions has evolved. Rather than focusing on the visual developments, the primary aim of this thesis is to render visible the processes and operations of the stereoscopic technology employed to realise this 3D imagery in the first place. Utilising a media archaeological approach indebted to Wolfgang Ernst’s notion of “reverse engineering” technical media objects, I intend to analyse the primary technical components of digital and analogue 3D recording, projection and viewing devices utilised in the production of stereoscopic motion pictures. Moreover, Jonathan Crary’s writings on “the observer” will be used to highlight the important role of the human subject in relation to these binocular media technologies. I conclude that despite the varying production contexts and traditions the digital and analogue formats have been developed in, the primary methods and techniques that characterise digital 3D recording, projection and viewing systems are not specifications simply invented from scratch during the digital age. Through close scrutiny of the stereoscopic systems’ configurations with the aid of Ernst’s media archaeological approach, we are able to trace these supposed developments of the digital age back to the 19th century, when 3D was first realised.

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Machado, Karina Scurupa. « Anthropogenic and climate changes observed by biomarkers in paleogeochemical studies ». reponame:Repositório Institucional da UFPR, 2014. http://hdl.handle.net/1884/36785.

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Orientador : Prof. Dr. Sandro Froehner
Tese (doutorado) - Universidade Federal do Paraná, Setor de Tecnologia, Programa de Pós-Graduação em Engenharia de Recursos Hídricos e Ambiental. Defesa: Curitiba, 06/10/2014
Inclui referências
Resumo: Este estudo apresenta uma avaliação do potencial de biomarcadores na construção de cenários passados. Registros de mudanças ambientais ocorridas em duas áreas de estudo distintas foram obtidos a partir do uso de biomarcadores de mudanças antropogênicas e climáticas em sedimentos datados.Mudanças ambientais ocorridas a mil anos atrás foram estudadas na bacia do Lago Ohrid (Sudoeste da Macedônia), enquanto alterações mais recentes, nos últimos 400 anos, foram avaliadas na região norte de Curitiba e Almirante Tamandaré (Sul do Brasil). O ultimo milênio corresponde ao final do Holoceno, no qual ocorreram importantes eventos climáticos da história do planeta, tais como a Era Negra, Período Medieval Quente (PMQ), Pequena Idade do Gelo (PIG) e a Idade Moderna. No Lago Ohrid, alterações na quantidade e composição da matéria orgânica no sedimento foram observadas. A distribuição de lipídios mostrou uma substituição de fontes de matéria orgânica de plantas por solo e consequente aumento da produtividade no lago. Esta alteração se deve ao aumento do desmatamento na área devido a eventos históricos tais como a fundação do Monastério Saint Naum e a elevação da cidade de Ohrid a capital do Império Búlgaro. Associado a influência humana na região está o aumento das chuvas, característico da transição da Era Negra (frio e seco) para o PMQ (quente e úmido). Outro cenário foi observado no sul do Brasil, com mudanças mais recentes, referentes a transição da PIG para a Idade Moderna. Evidências de alterações na vegetação, clima e composição atmosférica foram discutidas e de maneira geral, três estágios foram observados: 1600-1730, mais quente e seco, predomínio de plantas herbáceas sobre lenhosas, 1730-1800, mais frio e seco, predomínio de plantas lenhosas e 1800- presente, final da PIG, mais quente e úmido. Do ponto de vista atmosférico, alterações nos níveis de CO2 parecem ter ocorrido nos últimos 400 anos. Com base na razão isotópica de plantas, dois aumentos significativos foram observados entre 1600-1880 e 1930-2012. Fontes de CO2 com influência global seriam as principais responsáveis pelo primeiro aumento, enquanto fontes regionais parecem ser predominantes no segundo. Dentre as fontes em nível global, o vulcanismo pode ter contribuído para a mudança na composição atmosférica, principalmente entre 1600 e 1880, uma vez que alterações no pH do solo são evidentes. No período mais recente, o aumento do CO2 atmosférico foi atribuído a fontes antropogênicas, tais como queima de biomassa e combustíveis fosseis. O impacto antrópico na região foi avaliado através da distribuição de hidrocarbonetos poliaromáticos, cujas fontes indicaram a evolução das atividades humanas na região nos últimos 150 anos, de forma a complementar o entendimento da mudança na composição atmosférica. De maneira geral, o presente estudo contribui para a elucidação das alterações ambientais ocorridas em períodos significativos da história, em regiões onde informações desta natureza são escassas. Em tempos de discussão sobre mudanças climáticas, o entendimento de eventos do passado, que podem vir a se repetir em um ciclo, e dos reais efeitos da ação do homem no planeta, contribuem para a construção de cenários e previsões futuras. Palavras-chave: Variações Climáticas, Impacto Antrópico, Biomarcadores, Holoceno
Abstract: This study presents an assessment of the potential of biomarkers in the construction of past scenarios. Records of environmental changes in two distinct areas of study were obtained from the use of biomarkers from anthropogenic and climate changes in dated sediment cores. Changes that occurred between 840 to 1330 were studied in Lake Ohrid watershed (Southwest Macedonia), while more recent changes, in the last 400 years, were evaluated in the northern region of Curitiba and Almirante Tamandaré (Southern Brazil). The last millennium corresponds to the late Holocene climate in which important events in the history of the planet, such as the Dark Age, Medieval Warm Period-MWP, Little Ice Age-LIA, and the Modern Age occurred. In Lake Ohrid, changes in the amount and composition of organic matter inputted in the sediment were observed. The distribution of lipids showed a replacing of organic matter sources from plants by soil and a consequent increase in productivity in the lake. This change is related to increased deforestation in the area due to historical events, such as the foundation of the Saint Naum monastery and the elevation of Ohrid City to the capital of the Bulgarian Empire. Associated with human influence in the region is increased rainfall, characteristic of the transition from the Dark Age (colder and dry) for the MWP (warmer and humid). Another scenario was observed in southern Brazil, with more recent changes regarding the transition from LIA to the Modern Time. Evidence of changes in vegetation, climate and atmospheric composition were discussed, and in general, three periods were observed: 1600-1730, warmer and dry, predominance of herbaceous over woody plants; 1730-1800, colder and dry, predominance of woody plants and 1800-nowadays, the end of LIA, warmer and more humid. From the atmospheric compartment, changes in CO2 levels appear to have occurred in the last 400 years. Based on the isotopic ratios from plant sources, two significant increases were observed between 1600-1880 and 1930-2012. Sources of CO2 with global influence would be primarily responsible for the initial increase, while regional sources seem to be predominant in the second. Among the global sources, volcanism may have contributed to the change in atmospheric composition, especially between 1600 and 1880, since changes in soil pH were evident. More recently, the rise of atmospheric CO2 has been attributed to anthropogenic sources such as biomass and fossil fuels burning. The anthropogenic impact on the region was assessed through the distribution of polyaromatic hydrocarbons, whose sources have indicated the evolution of human activities in the region over the past 150 years, complementing the understanding of changes in atmospheric composition. Overall, this study contributes to the elucidation of environmental changes in significant periods of history, in regions where information of this approach are scarce. In times of strong discussion about climate change, the understanding of past events that may be repeated in a cycle and the real effects of human actions on the planet contribute to the construction of future scenarios and forecasts. Keywords: Climate Changes, Anthropogenic Impact, Biomarkers, Holocene

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Keil, Ralf. « X-ray studies of ultraluminous infrared galaxies observed with XMM-Newton ». [S.l.] : [s.n.], 2006. http://deposit.ddb.de/cgi-bin/dokserv?idn=979447313.

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Chu, Eric (Eric Kwok-Wai). « Urban adaptations observed : the politics of governing climate resilience in Indian cities ». Thesis, Massachusetts Institute of Technology, 2015. http://hdl.handle.net/1721.1/99081.

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Thesis: Ph. D. in Environmental Policy and Planning, Massachusetts Institute of Technology, Department of Urban Studies and Planning, 2015.
Cataloged from PDF version of thesis.
Includes bibliographical references (pages 199-223).
An increasing number of international policymakers and funders have strongly advocated for programs that integrate and support both climate change adaptation and urban development, arguing that combining these two objectives will help ensure the long-term resilience of cities. This dissertation delves into the cases of Bhubaneswar, Indore, and Surat in India and looks at how urban local governments plan, implement, and advocate for locally grounded, contextually relevant adaptation and development priorities within their jurisdictions given such external mandates and incentives. My findings highlight two interrelated ways to theorize changing institutional relationships between climate adaptation, development planning, and urban political economy. First, through a process that I call street-level resilience making, I find that adaptation planning, implementation, and governance relies on the experimentation and co-creation of adaptation options between urban sectors and actors. Secondly, I show that urban adaptation is governed through power in translation, where different urban actors, groups, and communities contest intervening authorities through their ability to translate climate information, adaptation needs, and resilience-building options. In this context, cities are not in fact unidirectional recipients of external aid and support; rather, cities are taking ownership over how external funds get implemented, which urban actors participate in the process, and why certain sectors and populations receive more support than others. However, as cities gain authority over how external adaptation mandates get translated into concrete programs and interventions, this simultaneously creates more opportunities for local authorities to exclude certain populations in the process. The pursuit of urban resilience can therefore become a moniker for further co-optation of political power and for entrenching existing urban socioeconomic injustices. In response to rising urban inequalities attributed to current and pipeline adaptation interventions, I present a framework for evaluating climate justice from below. This concept takes into account how adaptation is mainstreamed into urban development and its relationship to broader socioeconomic transformations at a global scale. I conclude that the ability to mitigate existing power imbalances rests on the restructuring of governance arrangements available to marginalized communities to advocate for their own interests in the street-level resilience-making process.
by Eric Chu.
Ph. D. in Environmental Policy and Planning

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Ton, That Long. « Nonlinear control studies for circadian models in system biology ». Thesis, University of Manchester, 2011. https://www.research.manchester.ac.uk/portal/en/theses/nonlinear-control-studies-for-circadian-models-in-system-biology(f616f360-99e4-4314-ba51-be7a49e9ff0e).html.

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Circadian rhythms exist in almost all of living species, and they occupy an important role in daily biological activities of these species. This thesis deals with reduction of measurements in circadian models, and recovery of circadian phases. Two mathematical models of circadian rhythms are considered, with a 3rd order model for Neurospora, and a 7th order model for Mammals. The reduction of measurements of circadian models is shown by the proposals of observer designs to the two mathematical models of circadian rhythms. Both mathematical models contain strong nonlinearities, which make the observer design challenging. Two observer designs, reduced-order and one-sided Lipschitz, are applied to the circadian models to tackle the nonlinearities. Reduced-order observer design is based on a state transformation to make certain nonlinearities have no impact on the observer errors, and the design of one-sided Lipschitz observer is based on systems with one-sided Lipschitz nonlinearities. Both observer designs are based on the existing methods in literature. The existing method of reduced-order observer has been applied to a class of multi-output nonlinear systems. A new reduced-order observer design which extends the existing one in literature is presented in this thesis. In this new reduced-order observer method, the observer error dynamics can be designed by choosing the observer gain, unlike the existing one, of which the observer error dynamics depend on the invariant zeros under certain input-output map. The recovery of circadian phases is carried out to provide a solution to phase shifts occurred in circadian disorders. The restoration of circadian phases is performed by the synchronizations of trajectories of a controlled model with trajectories of a reference model. The reference model and the controlled model have phase differences, and both these models are based on a given 3rd order model of Neurospora circadian rhythms. The phase differences are reflected by different initial conditions, and by parameter uncertainty. The synchronizations of the two models are performed by using back-stepping method for the case of different initial conditions, and by using adaptive back-stepping method for the remaining case. Several simulation studies of the proposed observer designs and the proposed schemes of synchronizations are carried out with the results shown in this thesis.

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Yasui, Miwa. « Observed ethnic-racial socialization and early adolescent adjustment ». Thesis, Connect to title online (Scholars' Bank) Connect to title online (ProQuest), 2008. http://hdl.handle.net/1794/8303.

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Thesis (Ph. D.)--University of Oregon, 2008.
Typescript. Includes vita and abstract. Includes bibliographical references (leaves 143-150). Also available online in Scholars' Bank; and in ProQuest, free to University of Oregon users.

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Ishii, Mamoru. « Studies of the Small-Scale Magnetic and Electric Field Perturbations Observed in the Polar Ionosphere ». 京都大学 (Kyoto University), 1993. http://hdl.handle.net/2433/86253.

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Teramoto, Mariko. « Studies on Pi2 Pulsations in the Inner Magnetosphere Observed by Polar and Equatorial Orbiting Satellites ». 京都大学 (Kyoto University), 2010. http://hdl.handle.net/2433/120667.

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Willing, Josephine. « Användning av perspektiv i svenskt teckenspråk hos hörande andraspråksinlärare ». Thesis, Stockholms universitet, Institutionen för lingvistik, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-174636.

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I denna studie undersöker jag hur hörande vuxna andraspråksinlärare (L2) använder och utvecklar perspektiv i tre olika kategorier: karaktärens, observatörens ochblandat perspektivi svenskt teckenspråk under en tidsperiod på ett år. Målgruppens resultat har jämförts med en kontrollgrupp bestående av döva förstaspråkstalare (L1). Resultatet visar att målgruppen från andra inspelningstillfället till fjärde inspelningstillfället har utvecklat flera perspektiv i alla kategorier. När det gäller språkliga likheter och skillnader mellan målgruppen och kontrollgruppen är en tydlig likhet att alla uttrycker sina imiterande gester på samma sätt. Resultatet visar också att flera informanter i målgruppen använder dubbla referenter i teckenrummet. Det kan bero på att de föredrar observatörperspektivet eftersom de har svårigheter med blandat perspektiv. Kontrollgruppen har istället betydligt högre andel blandat perspektiv än målgruppen.
In this study, I investigate how hearing adult second language (L2) learners use and develop perspective in the three different categories – character, observerand mixed perspective– in Swedish Sign Language over the course of one year. The results of the target group are compared to those of a control group consisting of deaf first language (L1) users. The results show that the target group, between the second and fourth recording session, has developed multiple perspectives in all categories. Furthermore, linguistic similarities and differences between target and control groups are investigated, one similarity being that all informants express imitating gestures in the same way. The results show that several informants in the target group use double referents in signing space. This may be a consequence of their preference for observer perspective, since they have difficulties with mixed perspectives. Conversely, the control group has a considerably higher percentage of mixed perspectives than the target group.

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Zargar, Cameron. « The Hanbali and Wahhabi Schools of Thought as Observed Through the Case of Ziyarah ». The Ohio State University, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=osu1398829915.

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Bjälkenfalk, Katrin, et Sofi Peters. « Stimulerad & ; observerad : En studie kring sensorisk stimuli och dess påverkan ». Thesis, Linnéuniversitetet, Ekonomihögskolan, ELNU, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-20202.

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The purpose of this thesis is to see how small differences in a store can affect the customer behavior. The changes consist of auditory and visual sensory cues. Since many companies today makes a lot of changes in their styling element, but without knowing how it really affects the customer behavior we thought it would be interesting to see by doing an experiment at IKEA. The study is therefore based on a quantitative research method, where theories have been described and from which hypotheses have been derived to test the theories. The experience took place at IKEA during two weeks where 5732 observations were made. The result from the experiment is that the sensory cue sight makes individuals spend more time in the environment but not creating attention. By combining the sensory cues visual and sound attention increased but not the amount of time spend in the environment. We can also see that the positive effect from one sensory cue actually can be decreased by adding another one.

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Damian, Camilla, Zehra Eksi-Altay et Rüdiger Frey. « EM algorithm for Markov chains observed via Gaussian noise and point process information : Theory and case studies ». De Gruyter, 2018. http://dx.doi.org/10.1515/strm-2017-0021.

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In this paper we study parameter estimation via the Expectation Maximization (EM) algorithm for a continuous-time hidden Markov model with diffusion and point process observation. Inference problems of this type arise for instance in credit risk modelling. A key step in the application of the EM algorithm is the derivation of finite-dimensional filters for the quantities that are needed in the E-Step of the algorithm. In this context we obtain exact, unnormalized and robust filters, and we discuss their numerical implementation. Moreover, we propose several goodness-of-fit tests for hidden Markov models with Gaussian noise and point process observation. We run an extensive simulation study to test speed and accuracy of our methodology. The paper closes with an application to credit risk: we estimate the parameters of a hidden Markov model for credit quality where the observations consist of rating transitions and credit spreads for US corporations.

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Wong, Marina Wai-yee. « Elementary teachers' expressed beliefs and observed practices of music education in Vancouver and Hong Kong, a descriptive, exploratory study ». Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape7/PQDD_0017/NQ46451.pdf.

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Frisk, Anders. « Danslärarkroppen som resonanslåda : en hermeneutisk fenomenologisk studie om danslärares upplevelser av att observera (sin) dansundervisning ». Thesis, Stockholms konstnärliga högskola, Institutionen för danspedagogik, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:uniarts:diva-543.

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Abstract Title: The dance-teacher body as a sounding board - a hermeneutic phenomenological study about dance-teachers experiences observing (their own) dance education. Author: Anders Frisk, Stockholm University of the Arts - School of Dance and Circus Language: Swedish Key words: Dance, dance teacher, dance education, dance pedagogy, phenomenology, kinaesthetic empathy, interaffectivity, bodily resonance The aim of this study is to give insights into how dance teachers experience observing (their own) dance lessons. The interest lies in what they are reacting to and what gives an action in the form of feedback, guiding or ending an exercise, and how these reactions and actions are manifested in the body. Two teachers at the Swedish school of sport and health sciences (GIH) in Stockholm were observed and filmed during dance lessons with PE&H-student teachers. The subject of the lessons were experiencing and exploring dance as expressive form. From the videos of the lessons, different situations were chosen and discussed during a so-called re-experiencing interview. The interviews were transcribed and the text has been analysed using a hermeneutic phenomenological method. The analysis resulted in the following findings: To observe one’s own teaching seems to be a valuable tool for the teachers in order to reflect upon didactical considerations and possibilities for developing the teaching. The teachers seem to react on (lack of) movement, presence, focus and movement qualities. This creates a dissonance in their own bodily resonance that seems to create an embodied experience that they react upon. They act by guiding the students by adding more movement, verbal affirmation or instruction, metaphors or by ending the exercise. Sometimes they postponed reacting in order to give the students a chance to find their way back in focus. The teachers also have a focus on creating a learning environment where the aim is for the students to explore and to experience their own bodily resonance and how this can relate to other bodies. It seems that the teachers show a sensibility for the situation and the harmony in the dance studio that could be derived from a professional-personal competence or from an embodied practical pedagogical knowledge. The results of the study are discussed with the concepts of interaffectivity, mutual incorporation and kinaesthetic empathy. By raising awareness around how bodily (and embodied) interactions are intertwined within dance education these concepts might help and support the development of teaching in this specific context.

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Belova, Alla. « Studies of planetary waves in ozone and temperature fields as observed by the Odin satellite in 2002-2007 ». Doctoral thesis, Umeå University, Physics, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-1819.

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The results presented in this PhD thesis are mainly based on measurements collected by the advanced sub-mm radiometer (SMR) aboard the Odin satellite in 2002-2007. The primary data are series of temperature and ozone profiles in the middle atmosphere up to 68 km. These data are used to estimate global properties of planetary wave propagation in both horizontal and vertical directions. As good-quality retrievals from Odin are not available above 68 km, additional data sources have been considered in order to extend coverage of planetary wave properties to higher levels. These sources are temperature observations at 85-90 km obtained by the ground-based meteor radars located in the polar region in the Northern Hemisphere in Scandinavia at Esrange and at Andenes, and in Canada at Resolute Bay and at Yellowknife. Also, the series of ozone profiles from the ground-based Kiruna mm-wave radiometer, KIMRA, are used in order to compare the wave properties in ozone fields measured globally by Odin and locally by KIMRA.

The main task of this PhD thesis is to study the 5-day planetary wave characteristics in the Earth’s atmosphere. The influence of waves on the atmospheric circulation causes, for example, substantial local departures from radiative equilibrium, observed in the winter stratosphere and close to the summer mesopause. Seasonal variations of the 5-day planetary wave properties and physical phenomena related to these variations are also studied in this thesis.

During winter, planetary waves propagate freely in the vertical direction, and maximal wave amplitudes are found in the extratropical stratosphere. The Northern Hemisphere (NH) winter periods of 2002-2003 and 2005 have been examined and a comparison has been carried out between the planetary wave properties in temperature and ozone variations. In general, the results show an expected in-phase behavior between the temperature and ozone fields in the lower stratosphere (due to dynamic effects) and an out-of-phase pattern in the upper stratosphere (which is expected as a result of photochemical effects).

Earlier theoretical and experimental studies have shown that, despite unfavourable summertime wind conditions, 5-day planetary waves can be registered not only in the stratosphere but also at higher altitudes in the mesosphere. The NH summers of 2003-2005 and 2007 have been considered and results have confirmed the existence of 5-day planetary waves up to the mesopause level (85-90 km). The results demonstrate that, for different periods, the possible source of the observed waves could be located at lower altitudes in both hemispheres with successive propagation into the summer mesosphere, or the waves could be generated in-situ as a result of the baroclinic instability of summer easterly jet.

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Jackson, Clive Andrew. « Combined channel sounding and direction finding studies of HF radio propagation effects observed over high latitude communication paths ». Thesis, University of Leicester, 2003. http://hdl.handle.net/2381/30208.

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The high latitude ionosphere is a dynamic region that is subject to a variety of disturbed conditions affecting oblique propagation of HF radio signals. Multipath and off great circle propagation resulting from rough ionospheric reflecting surfaces introduce time dispersion, while movements in the ionosphere impose Doppler dispersion. These effects, when combined, result in very complex signal characteristics, which cause degradation to the performance of communication systems if the delay or Doppler dispersion exceeds system dependent bounds.;Results are presented based around measurements of signals, produced by the Doppler And Multipath SOunding Network, recorded using a six channel spaced array receiving system, during a 10 day campaign at Kiruna in March 1998. In addition to delay and Doppler processing, the directions of arrival (DOA) of the signal components were estimated using a super resolution direction finding algorithm.;Most signals were narrow in delay and Doppler, however a significant statistical spread in their DOA was observed. Statistics on the occurrence and characteristics of the remaining signals revealed that trends in DOA are often associated with complex delay and Doppler propagation. A number of cases had Doppler spread exceeding a specified Doppler boundary of operation, while none exceeded the delay spread boundary.;Case studies revealed detailed propagation effects. Of particular interest is the often observed East â†’ West trend in DOA with Doppler offset. This is attributed to scattering from irregularities embedded in turbulent bulk convection flows. E-region modes with good spectral and geographic distribution of signal energy are often observed in otherwise complex cases.;Spatial filtering, using two or three element arrays was investigated and found to be effective at reducing large Doppler spreads to lower values more amenable to high data rate communication systems. Fast solver spatial filtering methods were found to be very robust, effective and a lot quicker.

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Knutsen, Arijana. « Att observera och sortera i närmiljön : en variationsteoretisk studie av systematiskaundersökningar av närmiljön i F-3 ». Thesis, Luleå tekniska universitet, Pedagogik, språk och Ämnesdidaktik, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-82016.

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Denna studie har haft som syfte att vinna kunskap om hur elever i F-3 kan utveckla sin förmåga att göra observationer och sortera några vanligt förekommande trädarter i sin närmiljö. I studien har variationsteorin och det sociokulturella lärandeperspektivet använts som ramverk för att besvara de tre ställda forskningsfrågorna om vilka kritiska aspekter som måste synliggöras för att eleverna ska utveckla förmågan att observera och sortera, att känna igen några trädarter i närmiljön vintertid och hur undervisning kan möjliggöra detta. I bakgrunden behandlas tidigare forskning om naturvetenskaplig undervisning och lärande, elevers förståelse för de naturvetenskapliga arbetsmetoderna, samt elevers förståelse av vanligt förekommande träd- och växtarter i deras närmiljö, samt relevanta styrdokument. Data, i form av intervjuer och observationer, har samlats in från lektioner i en årskurs två bestående av 24 elever och med mig som lärare. Resultatet visar att lärare genom användandet av artefakter, mediering och variationsmönster i undervisningen kan skapa förutsättningar som möjliggör för eleverna att utveckla sin förmåga att observera och sortera. Resultatet visar även på att undervisningen även bidrog till att eleverna utvecklade sina kunskaper och kunde känna igen några vanligt förekommande kvistar från närmiljön.

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Wiman, Jacob. « Observing the Observers : A critical approach of problem representations in Policy of the EU EOM Final Reports ». Thesis, Uppsala universitet, Statsvetenskapliga institutionen, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-429515.

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Beckius, Göran. « Företagsetik : En studie av etiskt organiserande i några svenska företag ». Doctoral thesis, Stockholm University, School of Business, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-986.

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Although research in business ethics has of late received increased attention from researchers and practitioners, little has been written on the practical effects of its implementation.

The aim of the present study is, therefore, to explore the meaning and implications of business ethics from a practical perspective. To these ends, a qualitative study, mainly based on a grounded theory approach, has been carried out. The target of analysis is a corpus material derived from informants from 9 companies ranging from different sectors: 2 from the manufacturing sector, 1 company from the pharmaceutical sector and 6 companies from the financial sector.

The results show that almost all the companies under consideration have set up some ethical structures for implementing their ethical practices, and lived up to the embraced ethical values in their business conduct. The results also indicate that the companies have actually responded favorably to the requirements and demands of various stakeholders.

Furthermore, the emerging structures constitute the basis of a fully operative concept for organizing and implementing an ethical business conduct in organizations. This concept mainly consists of the following categories: ethics, rules, institutionalization, observing and abiding. These can all be applied separately or as a whole and as such be an instrument for measuring an organizations ethical level.

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Pachulia, Gocha, et Laura Henderson. « The relationship betweenEmotional Intelligence and Entrepreneurial Orientation : Observed within owner-managers who lead small, high-tech firms in Sweden ». Thesis, Jönköping University, JIBS, Business Administration, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:hj:diva-10297.

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Problem: Is there a statistically significant relationship between the EI of an ownermanager and the EO within a small firm?

Purpose: The primary purpose of this study was to perform an exploratory study of the research by addressing the first hypothesis. The secondary purpose of this study was to characterize the nature of this relationship by exploring micro-connections between EI and EO factors, by addressing the second hypothesis.

Hypotheses: 1) An owner-manager’s EI can be used to predict EO within small firms. 2) An owner-managers’ EI dimensions are positively correlated to the EO dimensions in small firms.

Method: A questionnaire including the EISDI (Emotional Intelligence) instrument and the Covin & Slevin (1989) Entrepreneurial Orientation (entrepreneurial/strategic posture) instrument were sent by email to respondents. Responses were collected from a sample of 35 respondents, who were identified as owner-managers of small, young firms within the Swedish high-tech industry. An empirical analysis examined correlations between global EI and global EO, as well as EI and EO factors.

Main findings: Both hypotheses were rejected. It was concluded that an owner-manager’s EI cannot be used to predict EO within small firms. Moreover, it was found that no part of an owner-manager’s EI is significantly nor strongly correlated to EO dimensions within small firms.

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Dick, Eric Timothy. « A survey of CT phantom considerations for the study of blooming artifacts as observed in CT coronary angiography studies a preliminary study / ». Cincinnati, Ohio : University of Cincinnati, 2008. http://www.ohiolink.edu/etd/view.cgi?acc_num=ucin1205313085.

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Thesis (M.S. of Medical Physics)--University of Cincinnati, 2008.
Advisor: Lisa Lemen PhD. Title from electronic thesis title page (viewed May 12, 2008). Includes abstract. Keywords: blooming; computed tomography; artifact; CT; beam hardening; partial volume averaging;cone beam. Includes bibliographical references.

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Biteau, Jonathan. « A window on stochastic processes and gamma-ray cosmology through spectral and temporal studies of AGN observed with H. E. S. S ». Palaiseau, Ecole polytechnique, 2013. http://pastel.archives-ouvertes.fr/pastel-00822242.

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Cinquante ans après la découverte de l'origine extragalactique des quasars, leurs noyaux (AGN) et les jets qu'ils montrent parfois nous réservent encore des surprises, en particulier dans le domaine des rayons gamma. Au dessus de 100 GeV, les télescopes Cherenkov tels que H. E. S. S. Ont détecté plus de 50 AGN, principalement des blazars, objets dont le jet pointe vers l'observateur. La détection de deux d'entre eux, 1ES 1312-423 et SHBL J001355. 9-185406, est décrite dans cette thèse. Leurs spectres multi longueurs d'onde sont ajustés par un modèle synchrotron self-Compton. Les rayons gamma émis par les blazars sont en partie absorbés par la lumière de fond extragalactique (EBL), deuxième composante cosmologique diffuse la plus intense, qui contient l'histoire intégrée de la formation d'étoiles. La première détection de cette absorption au dessus de 100 GeV est réalisée, conduisant à la mesure de l'amplitude du pic optique de l'EBL à 20% près. Finalement, les variations extrêmes du flux des blazars sont étudiées à l'aide des éruptions de PKS 2155-304 vues par H. E. S. S. . L'observation d'une distribution de flux hautement asymétrique et d'une corrélation R. M. S. -flux sont expliquées dans le cadre d'un modèle cinématique, où l'émission observée est une réalisation d'un processus stochastique
Fifty years after the discovery that quasars are extragalactic sources, their bright cores (AGN) and the jets that some of them exhibit still have plenty of secrets to share, particularly through observations in the gamma-ray band. Above 100 GeV, Cherenkov telescopes such as H. E. S. S. Have detected 50 AGN, mostly blazars, objects whose jets are pointed toward the observer. The detection of two faint ones, 1ES 1312-423 and SHBL J001355. 9-185406, is described in this thesis. Their multiwavelength spectra are reproduced with a synchrotron self-Compton model. The γ rays emitted by blazars are partly absorbed by the extragalactic background light (EBL), the second most intense cosmological background, which carries the integrated history of star formation. The first detection of this absorption above 100 GeV is performed, enabling the measurement of the EBL peak-amplitude in the optical band at the 20% level. In addition to these spectral studies, the fast flux-variations of blazars are investigated using the outbursts of PKS 2155-304 seen by H. E. S. S. . The observation of a skewed flux distribution and of an R. M. S. -flux correlation are interpreted within a kinematic model, where the emission is a realization of a stochastic process

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DICK, ERIC TIMOTHY. « A Survey of CT Phantom Considerations for the Study of Blooming Artifacts as Observed in CT Coronary Angiography Studies : A Preliminary Study ». University of Cincinnati / OhioLINK, 2008. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1205313085.

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Arntzen, Kamilla, et Jennie Hallberg. « "Den vuxnes roll är att lyfta leken en dimension eller bara observera" : En fenomenografisk studie om förskollärares erfarande av deltagande i leken ». Thesis, Högskolan Kristianstad, Sektionen för Lärarutbildning, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:hkr:diva-9380.

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Studiens syfte är att undersöka hur förskollärare erfar deltagandet i leken i förskolan. Forskningsfrågorna som studien utgår från är: Hur erfar förskollärare deltagandet i leken? och Hur erfar förskollärare svårigheter och möjligheter med deltagandet i leken? Bearbetningen av insamlad data är inspirerad av ett fenomenografiskt perspektiv, där förskollärarna ges möjlighet att berätta fritt om erfarandet kring deltagandet i leken. Intervjuerna är därför av kvalitativ karaktär. Det framkommer i resultatet att förskollärare ser på sin roll kring leken på olika sätt, som observatör, tillförare och medlekare. Några förskollärare belyser svårigheter med deltagandet, till exempel tidsbrist. I analysen visas de kvalitativa skillnaderna mellan förskollärarnas erfarande av deltagandet i leken. I den hierarkiska triangel som presenteras i resultatet och analysen visas de kvalitativa skilda kategorierna, där den mest komplexa kategorin innefattar pedagogers erfarande om rollen som medlekare och i den mest basala kategorin visas pedagogers erfarande om att det finns svårigheter med deltagandet i leken. Generellt kan det urskiljas av resultatet att förskollärarna är väl medvetna om nyare forskning som säger att deltagandet i leken på barns villkor är av stor betydelse. Dock påverkas deltagandet av många faktorer i det pedagogiska arbetet.

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Arntzen, Kamilla, et Jennie Hallberg. « "Den vuxnes roll är att lyfta leken en dimension eller bara observera" : En fenomenorgafisk studie om förskollärares erfarande av deltagande i leken ». Thesis, Högskolan Kristianstad, Sektionen för lärande och miljö, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:hkr:diva-9588.

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Studiens syfte är att undersöka hur förskollärare erfar deltagandet i leken i förskolan. Forskningsfrågorna som studien utgår från är: Hur erfar förskollärare deltagandet i leken? och Hur erfar förskollärare svårigheter och möjligheter med deltagandet i leken?Bearbetningen av insamlad data är inspirerad av ett fenomenografiskt perspektiv, där för-skollärarna ges möjlighet att berätta fritt om erfarandet kring deltagandet i leken. Intervju-erna är därför av kvalitativ karaktär.Det framkommer i resultatet att förskollärare ser på sin roll kring leken på olika sätt, som observatör, tillförare och medlekare. Några förskollärare belyser svårigheter med delta-gandet, till exempel tidsbrist.I analysen visas de kvalitativa skillnaderna mellan förskollärarnas erfarande av deltagandet i leken. I den hierarkiska triangel som presenteras i resultatet och analysen visas de kvalita-tiva skilda kategorierna, där den mest komplexa kategorin innefattar pedagogers erfarande om rollen som medlekare och i den mest basala kategorin visas pedagogers erfarande om att det finns svårigheter med deltagandet i leken.Generellt kan det urskiljas av resultatet att förskollärarna är väl medvetna om nyare forsk-ning som säger att deltagandet i leken på barns villkor är av stor betydelse. Dock påverkas deltagandet av många faktorer i det pedagogiska arbetet.

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Guarnieri, Gabriele. « High dynamic range images : processing, display and perceptual quality assessment ». Doctoral thesis, Università degli studi di Trieste, 2009. http://hdl.handle.net/10077/3121.

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2007/2008
The intensity of natural light can span over 10 orders of magnitude from starlight to direct sunlight. Even in a single scene, the luminance of the bright areas can be thousands or millions of times greater than the luminance in the dark areas; the ratio between the maximum and the minimum luminance values is commonly known as dynamic range or contrast. The human visual system is able to operate in an extremely wide range of luminance conditions without saturation and at the same time it can perceive fine details which involve small luminance differences. Our eyes achieve this ability by modulating their response as a function of the local mean luminance with a process known as local adaptation. In particular, the visual sensation is not linked to the absolute luminance, but rather to its spatial and temporal variation. One consequence of the local adaptation capability of the eye is that the objects in a scene maintain their appearance even if the light source illuminating the scene changes significantly. On the other hand, the technologies used for the acquisition and reproduction of digital images are able to handle correctly a significantly smaller luminance range of 2 to 3 orders of magnitude at most. Therefore, a high dynamic range (HDR) image poses several challenges and requires the use of appropriate techniques. These elementary observations define the context in which the entire research work described in this Thesis has been performed. As indicated below, different fields have been considered; they range from the acquisition of HDR images to their display, from visual quality evaluation to medical applications, and include some developments on a recently proposed class of display equipment. An HDR image can be captured by taking multiple photographs with different exposure times or by using high dynamic range sensors; moreover, synthetic HDR images can be generated with computer graphics by means of physically-based algorithms which often involve advanced lighting simulations. An HDR image, although acquired correctly, can not be displayed on a conventional monitor. The white level of most devices is limited to a few hundred cd/m² by technological constraints, primarily linked to the power consumption and heat dissipation; the black level also has a non negligible luminance, in particular for devices based on the liquid crystal technology. However, thanks to the aforementioned properties of the human visual system, an exact reproduction of the luminance in the original scene is not strictly necessary in order to produce a similar sensation in the observer. For this purpose, dynamic range reduction algorithms have been developed which attenuate the large luminance variations in an image while preserving as far as possible the fine details. The most simple dynamic range reduction algorithms map each pixel individually with the same nonlinear function commonly known as tone mapping curve. One operator we propose, based on a modified logarithmic function, has a low computational cost and contains one single user-adjustable parameter. However, the methods belonging to this category can reduce the visibility of the details in some portions of the image. More advanced methods also take into account the pixel neighborhood. This approach can achieve a better preservation of the details, but the loss of one-to-one mapping from input luminances to display values can lead to the formation of gradient reversal effects, which typically appear as halos around the object boundaries. Different solutions to this problem have been attempted. One method we introduce is able to avoid the formation of halos and intrinsically prevents any clipping of the output display values. The method is formulated as a constrained optimization problem, which is solved efficiently by means of appropriate numerical methods. In specific applications, such as the medical one, the use of dynamic range reduction algorithms is discouraged because any artifacts introduced by the processing can lead to an incorrect diagnosis. In particular, a one-to-one mapping from the physical data (for instance, a tissue density in radiographic techniques) to the display value is often an essential requirement. For this purpose, high dynamic range displays, capable of reproducing images with a wide luminance range and possibly a higher bit depth, are under active development. Dual layer LCD displays, for instance, use two liquid crystal panels stacked one on top of the other over an enhanced backlight unit in order to achieve a dynamic range of 4 ÷ 5 orders of magnitude. The grayscale reproduction accuracy is also increased, although a “bit depth” can not be defined unambiguously because the luminance levels obtained by the combination of the two panels are partially overlapped and unevenly spaced. A dual layer LCD display, however, requires the use of complex splitting algorithms in order to generate the two images which drive the two liquid crystal panels. A splitting algorithm should compensate multiple sources of error, including the parallax introduced by the viewing angle, the gray-level clipping introduced by the limited dynamic range of the panels, the visibility of the reconstruction error, and glare effects introduced by an unwanted light scattering between the two panels. For these reasons, complex constrained optimization techniques are necessary. We propose an objective function which incorporates all the desired constraints and requirements and can be minimized efficiently by means of appropriate techniques based on multigrid methods. The quality assessment of high dynamic range images requires the development of appropriate techniques. By their own nature, dynamic range reduction algorithms change the luminance values of an image significantly and make most image fidelity metrics inapplicable. Some particular aspects of the methods can be quantified by means of appropriate operators; for instance, we introduce an expression which describes the detail attenuation introduced by a tone mapping curve. In general, a subjective quality assessment is preferably performed by means of appropriate psychophysical experiments. We conducted a set of experiments, targeted specifically at measuring the level of agreement between different users when adjusting the parameter of the modified logarithmic mapping method we propose. The experimental results show a strong correlation between the user-adjusted parameter and the image statistics, and suggest a simple technique for the automatic adjustment of this parameter. On the other hand, the quality assessment in the medical field is preferably performed by means of objective methods. In particular, task-based quality measures evaluate by means of appropriate observer studies the clinical validity of the image used to perform a specific diagnostic task. We conducted a set of observer studies following this approach, targeted specifically at measuring the clinical benefit introduced by a high dynamic range display based on the dual layer LCD technology over a conventional display with a low dynamic range and 8-bit quantization. Observer studies are often time consuming and difficult to organize; in order to increase the number of tests, the human observers can be partially replaced by appropriate software applications, known as model observers or computational observers, which simulate the diagnostic task by means of statistical classification techniques. This thesis is structured as follows. Chapter 1 contains a brief background of concepts related to the physiology of human vision and to the electronic reproduction of images. The description we make is by no means complete and is only intended to introduce some concepts which will be extensively used in the following. Chapter 2 describes the technique of high dynamic range image acquisition by means of multiple exposures. In Chapter 3 we introduce the dynamic range reduction algorithms, providing an overview of the state of the art and proposing some improvements and novel techniques. In Chapter 4 we address the topic of quality assessment in dynamic range reduction algorithms; in particular, we introduce an operator which describes the detail attenuation introduced by tone mapping curves and describe a set of psychophysical experiments we conducted for the adjustment of the parameter in the modified logarithmic mapping method we propose. In Chapter 5 we move to the topic of medical images and describe the techniques used to map the density data of radiographic images to display luminances. We point out some limitations of the current technical recommendation and propose an improvement. In Chapter 6 we describe in detail the dual layer LCD prototype and propose different splitting algorithms for the generation of the two images which drive the two liquid crystal panels. In Chapter 7 we propose one possible technique for the estimation of the equivalent bit depth of a dual layer LCD display, based on a statistical analysis of the quantization noise. Finally, in Chapter 8 we address the topic of objective quality assessment in medical images and describe a set of observer studies we conducted in order to quantify the clinical benefit introduced by a high dynamic range display. No general conclusions are offered; the breadth of the subjects has suggested to draw more focused comments at the end of the individual chapters.
XXI Ciclo
1982

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Englund, Carolina, et Anna Frenell. « Service recovery på social media och dess effekt på e-observatörers köpintentioner : En kvalitativ studie ». Thesis, Högskolan i Gävle, Avdelningen för ekonomi, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-27106.

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Syfte: Syftet med denna studie är att skapa en förståelse för hur ett företags service recovery på social media påverkar e-observatörers köpintentioner. Metod: Då studien syftar till att skapa en förståelse har en kvalitativ forskningsstrategi använts. Empirin utgörs av semistrukturerade intervjuer med tio respondenter. Som underlag för intervjuerna har två olika scenarier använts innehållande olika service recovery strategier. Den empiri som har samlats in har vidare bearbetats utifrån tematisk analys. Resultat & slutsats: Denna studie visar på att ett företags service recovery på social media påverkar e-observatörers köpintentioner. Ursäkt, kompensation och förklaring anses som de allra viktigaste service recovery strategierna på sociala medier. Detta eftersom dessa strategier har visat sig ha en positiv effekt på e-observatörers köpintentioner, medan en avsaknad av dessa strategier indikerar på en negativ påverkan. Examensarbetets bidrag: Studien påvisar att e-observatörer påverkas av ett företags service recovery på sociala medier. På vilket sätt företaget svarar en klagande kund kan ha en betydande effekt på den bild som observerande kunder får av företaget, vilket i sin tur påverkar deras köpintentioner. Ursäkt, kompensation och förklaring anses som viktiga faktorer vid företags hantering av klagomål. Förslag till fortsatt forskning: Våra förslag på framtida forskning är att studera andra sociala medier än Facebook, för att se om detta kan ha en effekt på hur e-observatörer påverkas av en service recovery-situation. Ett annat förslag är att undersöka vilken inverkan service recovery har på e-observatörer utifrån andra service recovery strategier än ursäkt och kompensation. Vidare kan det vara av intresse att undersöka om åsikter och intentioner skiljer sig åt mellan olika länder, en tvärkulturell studie är därför ytterligare ett förslag. Avslutningsvis ger vi även förslag på att studera en annan subgrupp och åldersgrupp, då vi studerat en specifik ålders- och subgrupp.
Aim: The aim of the study is to increase the understanding of how a company’s service recovery in social media, affects e-observers’ purchase intentions. Method: The aim of the study is to increase understanding, hence a qualitative method has been used. The empirical data was collected by semi-structured interviews with ten respondents. To support the interviews two scenarios has been used, including different service recovery strategies. The empirical data was further processed through thematic analysis. Result & Conclusions: The study shows that a company’s service recovery in social media, affects e-observers’ purchase intentions. Excuse, compensation and explanation are seen as the most important service recovery strategies in social media. This because all of these strategies have shown to positively affect e-observers’ purchase intentions, while a lack of these strategies has an opposite effect. Contribution of the thesis: Our study shows that a company’s service recovery in social media affects e-observers. In what way a company answers a complaining customer can have a crucial effect on the observing customers’ perception of the company, which in turn affects the e- observers’ purchase intentions. Excuse, compensation and explanation are seen as important factors when handling customer complaints. Suggestions for future research: Our suggestions for future studies is to investigate other social media than Facebook to see how e-observers are affected by a service-recovery-situation. Further, we suggest examining the impact of other service recovery strategies, besides excuse and compensation, on e-observers. It could be of interest to examine if opinions and intentions differ between different countries, i.e. a cross-cultural study. Finally, we have examined a specific subgroup (business students) and age group (16-35 years), hence we suggest examining different types of groups.

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Hopkins, Alan John. « Computer simulation studies of dense suspension rheology : computational studies of model sheared fluids : elucidation, interpretation and description of the observed rheological behaviour of simple colloidal suspensions in the granulo-viscous domain by non-equilibrium particulate dynamics ». Thesis, University of Bradford, 1989. http://hdl.handle.net/10454/4408.

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Rheological properties of idealised models which exhibit all the non-Newtonian flow phenomenology commonly seen in dense suspensions are investigated by particulate-dynamics computer-simulations. The objectives of these investigations are: (i) to establish the origins of various aspects of dense suspension rheology such as shear-thinning, shear thickening and dilatancy; (ii) to elucidate the different regions of a typical dense suspension rheogram by examining underlying structures and shear induced anisotropies in kinetic energy, diffusivity and pressure; (iii) to investigate the scaling of the simplest idealised model suspension; i.e. the hard-sphere model in Newtonian media and its relationship to the isokinetic flow curves obtained through non-equilibrium molecular dynamics (NEMD) simulations; (iv) to preliminarily determine the effect of perturbations present in all real colloidal suspensions, namely particle size polydispersity and a slight 'softness' of the interparticle potential. Non-equilibrium isokinetic simulations have been performed upon ;systems of particles interacting through the classical hard-sphere potential and a perturbation thereof, in which the hard-core is surrounded by a 'slightly soft' repulsive skin. The decision to base the present work upon isokinetic studies was made in order to obtain a better under- standing of suspension rheology by making a direct connection with previous NEMD studies of thermal systemst(93). These studies have shown that the non-linear behaviour exhibited by these systems under shear is atttributable to a shear-induced perturbation of the equilibrium phase behaviour. The present study shows this behaviour to correspond to the high shear region of the generalised suspension flow curve.

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Zilic, Ada. « Signifikanta skillnader i spirometrivariabler observerad mellan en Jaeger MasterScreen och en Vyntus spirometer : En jämförelse studie mellan två olika lungfunktionsutrustningar ». Thesis, Örebro universitet, Institutionen för hälsovetenskaper, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:oru:diva-84606.

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Introduktion: En av de vanligaste undersökningsmetoderna för att bedöma den respiratoriska funktionen är spirometri. Det är en undersökning som mäter lungvolymer och lungvolymsförändringar över tid. En fullständig lungfunktionsundersökning består av statisk och dynamisk spirometri samt mätning av diffusionskapacitet. Studiens syfte var att jämföra två olika utrustningar, en gammal (Jaeger MasterScreen Body och PFT) och en ny utrustning (Vyntus Body och One) om det fanns någon signifikant skillnad på mätresultatet mellan utrustningarna. Metod och material: Studien bestod av 24 testpersoner, 16 kvinnor och 8 män, alla undersökningar utfördes på Fysiologiska kliniken på Västerås sjukhus under februari och april 2020. Variablerna som undersöktes och bearbetades var vitalkapacitet (VK), forcerad vitalkapacitet (FVK), forcerad exspiratorisk volym på en sekund (FEV1), forcerad exspiratorisk volym uttryck i procent med vitalkapacitet (FEV%VK), total lungkapacitet (TLK), residualvolym (RV), mätning av diffusionskapacitet (DLCO) samt alveolär ventilation (VA). Resultat: Resultatet från studien visade att det förelåg en statistisk signifikant skillnad mellan utrustningarna Jaeger och Vyntus. Lungfunktionsutrustningen Vyntus påvisade ett lägre mätresultat på samtliga variabler. Att det förelåg en statistisk signifikant skillnad kan bero på att utrustningarna använder olika mätmetoder, Jaeger har en pneumotach medan Vyntus har en ultraljudssensor. Slutsats: Slutsatsen är att det föreligger systematisk skillnad på den nya utrustningen Vyntus. Vyntus visade lägre värden på samtliga variabler.
Introduction: One of the most common measurements for assessment of pulmonary function is spirometry. It is a method that measures lung volumes and changes in lung volume over time. A complete lung function test consists of static and dynamic spirometry as well as measurement of diffusion capacity. The purpose of the study was to compare two different equipment, an older (Jaeger MasterScreen Body and PFT) and the contemporary (Vyntus Body and One) if there was any significant difference in the measurement result between the two equipment. Method and materials: The study consisted of 24 test subjects, 16 women and 8 men, all examinations were performed at the Physiological Clinic at Västerås Hospital between February and April 2020. The variables investigated and processed were vital capacity (VC), forced vital capacity (FVC), forced expiratory volume in one second (FEV1), forced expiratory volume expression as a percentage with vital capacity (FEV%VC), total lung capacity (TLC), residual volume (RV), diffusion capacity measurement (DLCO) and alveolar ventilation (VA). Result: The results of the study showed that there was a statistical significant difference between the two equipments Jaeger and Vyntus. The lung function equipment Vyntus showed a lower measurement result on all variables. This statistical significant difference may be due to the fact that the equipment uses different measurement methods. Jaeger has a pneumotach while Vyntus has an ultrasonic sensor. Conclusion: The conclusion is that there is a systematic difference in the new Vyntus equipment. Vyntus showed lower values for all variables.

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Silva, Lais Mara Caetano da. « Elaboração e validação de um instrumento de avaliação da transferência do Tratamento Diretamente Observado da tuberculose segundo a perspectiva de profissionais de saúde de nível médio e superior (ATP-IINFOC-TB) ». Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/22/22133/tde-05052016-211603/.

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Compreendendo a tuberculose enquanto problema de saúde pública, desde meados dos anos 1990 a Organização Mundial da Saúde recomenda ações de controle da doença, dentre estas a Directly Observed Treatment Short-Course (DOTS) que, junto às demais recomendações, é transferida e executada em diferentes cenários, sendo essa transferência merecedora de atenção e aprofundamento, o que deve ocorrer por meio da utilização de métodos válidos e confiáveis. Trata-se de um estudo metodológico, cujo objetivo é elaborar e validar um instrumento voltado à avaliação da transferência da política do Tratamento Diretamente Observado, segundo a perspectiva de profissionais de saúde, por meio das dimensões \"Informação\", \"Conhecimento\" e \"Inovação\". O estudo foi realizado em três fases, a saber: validação semântica, primeira fase do estudo de campo e segunda fase do estudo de campo. A validação semântica contou com 24 profissionais; a primeira fase do estudo de campo, com 101 profissionais; e a segunda fase do estudo de campo, com 401 profissionais. Na validação semântica, o instrumento foi ajustado segundo as sugestões dos entrevistados, tendo ocorrido também a retirada de dois itens dos 49 inicialmente propostos. Na primeira fase do estudo de campo, o instrumento não apresentou efeito floor and ceiling e foram retirados 8 itens com carga fatorial < 0,30 na Análise Fatorial Exploratória. O instrumento apresentou um bom alfa de Cronbach (?=0,87), e a dimensão \"Conhecimento\" apresentou alfa baixo (?=0,645). Na segunda fase do estudo de campo, o efeito floor and ceiling manteve- se ausente, com baixo coeficiente de correlação linear de Pearson (r), baixo ajuste (55%) e baixo alfa de Cronbach (?=0,61) para a dimensão \"Conhecimento\", tendo as dimensões \"Informação\" e \"Inovação\" atingido valores aceitáveis. Para o instrumento como um todo, o Alfa de Cronbach foi de 0,872. O KMO e o Teste de Esfericidade de Bartlett foram satisfatórios, permitindo a Análise Fatorial Confirmatória. Entretanto, identificou-se baixo valor de ajuste do modelo no CFI e RMSEA (0,576 e 0,088, respectivamente), com uma baixa correlação entre as dimensões propostas. Conclui-se que o instrumento elaborado é capaz de avaliar a transferência do TDO segundo a perspectiva de profissionais de saúde de nível médio e superior de forma unidimensional, sem a utilização das três dimensões inicialmente propostas
Understanding tuberculosis as a public health problem since the mid-1990s, the World Health Organization recommended disease control actions, among them the Directly Observed Treatment Short-Course (DOTS) that, together with other recommendations, is transferred and executed in different scenarios, being this transfer worthy of attention and deepening, what should be made using valid and reliable methods. This is a methodological study, which aims to develop and validate a tool, which aims to assess the transfer of the Directly Observed Treatment policy, from the perspective of health professionals, through the dimensions \"Information\", \"Knowledge\" and \"Innovation \". The study was conducted in three stages, namely: semantic validation, the first phase of the field study and the second stage of the field study. The semantic validation was attended by 24 professionals; the first phase of the field study by 101 professionals; and the second phase of the field study by 401 professionals. In the semantic validation, the instrument was adjusted according to respondent\'s suggestions, having also been removed two of the 49 items initially proposed. In the first phase of the field study, the tool had no effect floor and ceiling, and were removed 8 items with factor loadings <0.30 in Exploratory Factor Analysis. The tool showed a good Cronbach\'s alpha (?=0.872), and the dimension \"Knowledge\" presented low alpha (?=0.645). In the second phase of the field study, the effect of floor and ceiling remained absent with a low Pearson\'s coefficient of linear correlation (r), a low fit (55%) and low Cronbach\'s alpha (?=0.61) for the dimension \"Knowledge\", having the dimensions \"Information\" and \"Innovation\" reached acceptable values, and the tool showed a good Cronhbach\'s Alpha (?=0,89). The KMO and Bartlett\'s sphericity test were satisfactory, allowing the Confirmatory Factor Analysis. However, it identified a low value of model\'s fit in CFI and RMSEA (0.576 and 0.088, respectively), with a low correlation between the proposed dimensions. It was concluded that the elaborated tool is able to assess the transfer of the Directly Observed Therapy from the perspective of mid and high-level health professionals in the unidimensional form, without the use of the three dimensions originally proposed

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Engel, Roxane. « The nuclear export of DNA topoisomerase iialpha in hematological myeloma cell lines as a function of drug sensitivity : clinical implications and a theoretical approach for overcoming the observed drug resistance / ». [Tampa, Fla.] : University of South Florida, 2005. http://purl.fcla.edu/fcla/etd/SFE0001358.

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Oschlisniok, Janusz [Verfasser], Martin [Gutachter] Pätzold et Andreas [Gutachter] Eckart. « Transport of sulfuric acid in the atmosphere of Venus studied on the basis of radio signal attenuation effects observed in the Venus Express Radio Science Experiment VeRa / Janusz Oschlisniok ; Gutachter : Martin Pätzold, Andreas Eckart ». Köln : Universitäts- und Stadtbibliothek Köln, 2020. http://d-nb.info/122171841X/34.

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Paula, Adriana Pereira de. « Aderência à terapêutica com antimicrobianos administrados por via oral em adultos com osteomielite ». Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/5/5140/tde-09102013-163716/.

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A osteomielite possui elevada prevalência e morbidade. O tratamento depende de apropriada terapia antimicrobiana por tempo prolongado e frequentemente requer cirurgia para remoção de tecidos necróticos. A aderência dos pacientes com osteomielite à prescrição do antibiótico, embora fundamental para o sucesso terapêutico, tem sido pouco estudada. O objetivo deste estudo foi mensurar a aderência à terapia antimicrobiana oral em pacientes adultos com osteomielite; identificar se alguns fatores relacionados na literatura estavam associados com a não aderência; estabelecer o valor preditivo dos fatores associados a não aderência ao tratamento em pacientes com osteomielite. Foi realizado um estudo transversal, fundamentado na avaliação por meio de métodos indiretos da aderência para 83 pacientes. Foram considerados pelo menos 30 dias de uso do antimicrobiano à entrevista e os pacientes foram classificados como aderentes de acordo com o questionário de Morisky, que é constituído por 4 questões com respostas dicotômicas para avaliar a aderência. Os pacientes com < 2 pontos foram considerados de baixa aderência e os que obtiverem > 3 pontos, de alta aderência. O presente estudo identificou uma prevalência de alta aderência de 83,1% (n=63). O ajuste dos modelos de regressão logística múltipla não resultou em variáveis conjuntas influenciando a aderência ao tratamento, porém pacientes do gênero masculino sugeriram apresentar maior frequência de baixa aderência ao tratamento em relação aos pacientes do gênero feminino (p = 0,053). Com relação à idade, a análise dos dados mostrou que os pacientes com idade entre 31 e 59 anos possuíam probabilidade de baixa aderência 68% menor que pacientes com idade entre 18 e 30 anos. A aderência observada foi semelhante à encontrada na literatura. Os fatores sociodemográficos podem interferir na aderência de pacientes em uso de antibióticos orais para tratamento de osteomielite
Osteomyelitis is a highly prevalent disease and a major cause of morbidity. Clinical treatment is based on appropriate antimicrobial therapy. Adherence of patients with osteomyelitis to the prescribed treatment, although critical for successful treatment, has been little studied. The aim of the study was: to measure the adherence to oral antimicrobial therapy in adult patients with osteomyelitis; to identify whether some of the factors listed in health literature were associated with non-adherence; to establish the predictive values associated with non-adherence to antimicrobial therapy in patients with osteomyelitis. We conducted a cross-sectional study, based on evaluation through indirect methods of adherence for 83 patients. We included patients receiving at least 30 days of antimicrobial use. Patients were interviewed and classified as adherent according to the Morisky questionnaire, that consists of 4 questions with dichotomous responses to assess adherence. Patients with 3 points, with high adherence. This study identified a prevalence of high adherence of 83.1% (n = 63). The multivariate logistic regression analysis did not result in multiple variables influencing adherence to treatment. Gender was the only variable with an suggested association with low adherence, male gender was more associated with low adherence than female (p = 0,053). Regarding age, data analysis showed that patients aged between 31 and 59 years had low adherence probability 68% lower than patients aged between 18 and 30 years. The high adherence observed in this study was similar than previous reported in the literature. Social and demographic factors may interfere in the adherence with patients using oral antibiotics for the treatment of osteomyelitis

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Moreira, Ana Sofia Pereira. « Study of modifications induced by thermal and oxidative treatment in oligo and polysaccharides of coffee by mass spectrometry ». Doctoral thesis, Universidade de Aveiro, 2016. http://hdl.handle.net/10773/17074.

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Doutoramento em Bioquímica
Os polissacarídeos são os componentes maioritários dos grãos de café verde e torrado e da bebida de café. Os mais abundantes são as galactomananas, seguindo-se as arabinogalactanas. Durante o processo de torra, as galactomananas e arabinogalactanas sofrem modificações estruturais, as quais estão longe de estar completamente elucidadas devido à sua diversidade e à complexidade estrutural dos compostos formados. Durante o processo de torra, as galactomananas e arabinogalactanas reagem com proteínas, ácidos clorogénicos e sacarose, originando compostos castanhos de alto peso molecular contendo nitrogénio, designados de melanoidinas. As melanoidinas do café apresentam diversas atividades biológicas e efeitos benéficos para a saúde. No entanto, a sua estrutura exata e os mecanismos envolvidos na sua formação permanecem desconhecidos, bem como a relação estrutura-atividade biológica. A utilização de sistemas modelo e a análise por espectrometria de massa permitem obter uma visão global e, simultaneamente, detalhada das modificações estruturais nos polissacarídeos do café promovidas pela torra, contribuindo para a elucidação das estruturas e mecanismos de formação das melanoidinas. Com base nesta tese, oligossacarídeos estruturalmente relacionados com a cadeia principal das galactomananas, (β1→4)-Dmanotriose (Man3), e as cadeias laterais das arabinogalactanas, (α1→5)-Larabinotriose (Ara3), isoladamente ou em misturas com ácido 5-Ocafeoilquínico (5-CQA), o ácido clorogénico mais abundante nos grãos de café verde, e péptidos compostos por tirosina e leucina, usados como modelos das proteínas, foram sujeitos a tratamento térmico a seco, mimetizando o processo de torra. A oxidação induzida por radicais hidroxilo (HO•) foi também estudada, uma vez que estes radicais parecem estar envolvidos na modificação dos polissacarídeos durante a torra. A identificação das modificações estruturais induzidas por tratamento térmico e oxidativo dos compostos modelo foi feita por estratégias analíticas baseadas principalmente em espectrometria de massa, mas também em cromatografia líquida. A cromatografia de gás foi usada na análise de açúcares neutros e ligações glicosídicas. Para validar as conclusões obtidas com os compostos modelo, foram também analisadas amostras de polissacarídeos do café obtidas a partir de resíduo de café e café instantâneo. Os resultados obtidos a partir dos oligossacarídeos modelo quando submetidos a tratamento térmico (seco), assim como à oxidação induzida por HO• (em solução), indicam a ocorrência de despolimerização, o que está de acordo com estudos anteriores que reportam a despolimerização das galactomananas e arabinogalactanas do café durante a torra. Foram ainda identificados outros compostos resultantes da quebra do anel de açúcares formados durante o tratamento térmico e oxidativo da Ara3. Por outro lado, o tratamento térmico a seco dos oligossacarídeos modelo (individualmente ou quando misturados) promoveu a formação de oligossacarídeos com um maior grau de polimerização, e também polissacarídeos com novos tipos de ligações glicosídicas, evidenciando a ocorrência de polimerização através reações de transglicosilação não enzimática induzidas por tratamento térmico a seco. As reações de transglicosilação induzidas por tratamento térmico a seco podem ocorrer entre resíduos de açúcares provenientes da mesma origem, mas também de origens diferentes com formação de estruturas híbridas, contendo arabinose e manose como observado nos casos dos compostos modelo usados. Os resultados obtidos a partir de amostras do resíduo de café e de café instantâneo sugerem a presença de polissacarídeos híbridos nestas amostras de café processado, corroborando a ocorrência de transglicosilação durante o processo de torra. Além disso, o estudo de misturas contendo diferentes proporções de cada oligossacarídeo modelo, mimetizando regiões do grão de café com composição distinta em polissacarídeos, sujeitos a diferentes períodos de tratamento térmico, permitiu inferir que diferentes estruturas híbridas e não híbridas podem ser formadas a partir das arabinogalactanas e galactomananas, dependendo da sua distribuição nas paredes celulares do grão e das condições de torra. Estes resultados podem explicar a heterogeneidade de estruturas de melanoidinas formadas durante a torra do café. Os resultados obtidos a partir de misturas modelo contendo um oligossacarídeo (Ara3 ou Man3) e 5-CQA sujeitas a tratamento térmico a seco, assim como de amostras provenientes do resíduo de café, mostraram a formação de compostos híbridos compostos por moléculas de CQA ligadas covalentemente a um número variável de resíduos de açúcar. Além disso, os resultados obtidos a partir da mistura contendo Man3 e 5-CQA mostraram que o CQA atua como catalisador das reações de transglicosilação. Por outro lado, nas misturas modelo contendo um péptido, mesmo contendo também 5-CQA e sujeitas ao mesmo tratamento, observou-se uma diminuição na extensão das reações transglicosilação. Este resultado pode explicar a baixa extensão das reações de transglicosilação não enzimáticas durante a torra nas regiões do grão de café mais ricas em proteínas, apesar dos polissacarídeos serem os componentes maioritários dos grãos de café. A diminuição das reações de transglicosilação na presença de péptidos/proteínas pode dever-se ao facto de os resíduos de açúcares redutores reagirem preferencialmente com os grupos amina de péptidos/proteínas por reação de Maillard, diminuindo o número de resíduos de açúcares redutores disponíveis para as reações de transglicosilação. Além dos compostos já descritos, uma diversidade de outros compostos foram formados a partir dos sistemas modelo, nomeadamente derivados de desidratação formados durante o tratamento térmico a seco. Em conclusão, a tipificação das modificações estruturais promovidas pela torra nos polissacarídeos do café abre o caminho para a compreensão dos mecanismos de formação das melanoidinas e da relação estrutura-atividade destes compostos.
Polysaccharides are the major components of green and roasted coffee beans, and coffee brew. The most abundant ones are galactomannans, followed by arabinogalactans. During the roasting process, galactomannans and arabinogalactans undergo structural modifications that are far to be completely elucidated due to their diversity and complexity of the compounds formed. During the roasting process, galactomannans and arabinogalactans react with proteins, chlorogenic acids, and sucrose, originating high molecular weight brown compounds containing nitrogen, known as melanoidins. Several biological activities and beneficial health effects have been attributed to coffee melanoidins. However, their exact structures and the mechanisms involved in their formation remain unknown, as well as the structure-biological activity relationship. The use of model systems and mass spectrometry analysis allow to obtain an overall view and, simultaneously, detailed, of the structural modifications in coffee polysaccharides promoted by roasting, contributing to the elucidation of the structures and formation mechanisms of melanoidins. Based on this thesis, oligosaccharides structurally related to the backbone of galactomannans, (β1→4)-D-mannotriose, and the side chains of arabinogalactans, (α1→5)-Larabinotriose, alone or in mixtures with 5-O-caffeoylquinic acid, the most abundant chlorogenic acid in green coffee beans, and dipeptides composed by tyrosine and leucine, used as models of proteins, were submitted to dry thermal treatments, mimicking the coffee roasting process. The oxidation induced by hydroxyl radicals (HO•) was also studied, since these radicals seem to be involved in the modification of the polysaccharides during roasting. The identification of the structural modifications induced by thermal and oxidative treatment of the model compounds was performed mostly by mass spectrometry-based analytical strategies, but also using liquid chromatography. Gas chromatography was used in the analysis of neutral sugars and glycosidic linkages. To validate the conclusions achieved with the model compounds, coffee polysaccharide samples obtained from spent coffee grounds and instant coffee were also analysed. The results obtained from the model oligosaccharides when submitted to thermal treatment (dry) or oxidation induced by HO• (in solution) indicate the occurrence of depolymerization, which is in line with previous studies reporting the depolymerization of coffee galactomannans and arabinogalactans during roasting. Compounds resulting from sugar ring cleavage were also formed during thermal treatment and oxidative treatment of Ara3. On the other hand, the dry thermal treatment of the model oligosaccharides (alone or when mixed) promoted the formation of oligosaccharides with a higher degree of polymerization, and also polysaccharides with new type of glycosidic linkages, evidencing the occurrence of polymerization via non-enzymatic transglycosylation reactions induced by dry thermal treatment. The transglycosylation reactions induced by dry thermal treatment can occur between sugar residues from the same origin, but also of different origins, with formation of hybrid structures, containing arabinose and mannose in the case of the model compounds used. The results obtained from spent coffee grounds and instant coffee samples suggest the presence of hybrid polysaccharides in these processed coffee samples, corroborating the occurrence of transglycosylation during the roasting process. Furthermore, the study of mixtures containing different proportions of each model oligosaccharide, mimicking coffee bean regions with distinct polysaccharide composition, subjected to different periods of thermal treatment, allowed to infer that different hybrid and non-hybrid structures may be formed from arabinogalactans and galactomannans, depending on their distribution in the bean cell walls and on roasting conditions. These results may explain the heterogeneity of melanoidins structures formed during coffee roasting. The results obtained from model mixtures containing an oligosaccharide (Ara3 or Man3) and 5-CQA and subjected to dry thermal treatment, as well as samples derived from spent coffee grounds, showed the formation of hybrid compounds composed by CQA molecules covalently linked to a variable number of sugar residues. Moreover, the results obtained from the mixture containing Man3 and 5-CQA showed that CQA acts as catalyst of transglycosylation reactions. On the other hand, in the model mixtures containing a peptide, even if containing 5-CQA and subjected to the same treatment, it was observed a decrease in the extent of transglycosylation reactions. This outcome can explain the low extent of non-enzymatic transglycosylation reactions during roasting in coffee bean regions enriched in proteins, although polysaccharides are the major components of the coffee beans. The decrease of transglycosylation reactions in the presence of peptides/proteins can be related with the preferential reactivity of reducing residues with the amino groups of peptides/proteins by Maillard reaction, decreasing the number of reducing residues available to be directly involved in the transglycosylation reactions. In addition to the compounds already described, a diversity of other compounds were formed from model systems, namely dehydrated derivatives formed during dry thermal treatment. In conclusion, the identification of the structural modifications in coffee polysaccharides promoted by roasting pave the way to the understanding of the mechanisms of formation of melanoidins and structure-activity relationship of these compounds.

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Lorsakul, Auranuch. « Objective Assessment of Image Quality : Extension of Numerical Observer Models to Multidimensional Medical Imaging Studies ». Thesis, 2015. https://doi.org/10.7916/D8Z60NB4.

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Encompassing with fields on engineering and medical image quality, this dissertation proposes a novel framework for diagnostic performance evaluation based on objective image-quality assessment, an important step in the development of new imaging devices, acquisitions, or image-processing techniques being used for clinicians and researchers. The objective of this dissertation is to develop computational modeling tools that allow comprehensive evaluation of task-based assessment including clinical interpretation of images regardless of image dimensionality. Because of advances in the development of medical imaging devices, several techniques have improved image quality where the format domain of the outcome images becomes multidimensional (e.g., 3D+time or 4D). To evaluate the performance of new imaging devices or to optimize various design parameters and algorithms, the quality measurement should be performed using an appropriate image-quality figure-of-merit (FOM). Classical FOM such as bias and variance, or mean-square error, have been broadly used in the past. Unfortunately, they do not reflect the fact that the average performance of the principal agent in medical decision-making is frequently a human observer, nor are they aware of the specific diagnostic task. The standard goal for image quality assessment is a task-based approach in which one evaluates human observer performance of a specified diagnostic task (e.g. detection of the presence of lesions). However, having a human observer performs the tasks is costly and time-consuming. To facilitate practical task-based assessment of image quality, a numerical observer is required as a surrogate for human observers. Previously, numerical observers for the detection task have been studied both in research and industry; however, little research effort has been devoted toward development of one utilized for multidimensional imaging studies (e.g., 4D). Limiting the numerical observer tools that accommodate all information embedded in a series of images, the performance assessment of a particular new technique that generates multidimensional data is complex and limited. Consequently, key questions remain unanswered about how much the image quality improved using these new multidimensional images on a specific clinical task. To address this gap, this dissertation proposes a new numerical-observer methodology to assess the improvement achieved from newly developed imaging technologies. This numerical observer approach can be generalized to exploit pertinent statistical information in multidimensional images and accurately predict the performance of a human observer over the complexity of the image domains. Part I of this dissertation aims to develop a numerical observer that accommodates multidimensional images to process correlated signal components and appropriately incorporate them into an absolute FOM. Part II of this dissertation aims to apply the model developed in Part I to selected clinical applications with multidimensional images including: 1) respiratory-gated positron emission tomography (PET) in lung cancer (3D+t), 2) kinetic parametric PET in head-and-neck cancer (3D+k), and 3) spectral computed tomography (CT) in atherosclerotic plaque (3D+e). The author compares the task-based performance of the proposed approach to that of conventional methods, evaluated based on a broadly-used signal-known-exactly /background-known-exactly paradigm, which is in the context of the specified properties of a target object (e.g., a lesion) on highly realistic and clinical backgrounds. A realistic target object is generated with specific properties and applied to a set of images to create pathological scenarios for the performance evaluation, e.g., lesions in the lungs or plaques in the artery. The regions of interest (ROIs) of the target objects are formed over an ensemble of data measurements under identical conditions and evaluated for the inclusion of useful information from different complex domains (i.e., 3D+t, 3D+k, 3D+e). This work provides an image-quality assessment metric with no dimensional limitation that could help substantially improve assessment of performance achieved from new developments in imaging that make use of high dimensional data.

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Leydesdorff, Loet. « The Biological Metaphor of a Second-Order Observer and the Sociological Discourse. Kybernetes 35 (3/4) (2006), 531-546 ». 2006. http://hdl.handle.net/10150/106240.

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Kybernetes 35 (3/4) (2006)
Purpose: In the tradition of Spencer Brown’s (1969) Laws of Form, observation was defined in Luhmann’s (1984) social systems theory as the designation of a distinction. In the sociological design, however, the designation specifies only a category for the observation. The distinction between observation and expectation enables the sociologist to appreciate the processing of meaning in social systems. Design: The specification of “the observer” in the tradition of systems theory is analyzed in historical detail. Inconsistencies and differences in perspectives are explicated, and the specificity of human language is further specified. The processing of meaning in social systems adds another layer to the communication. Findings: Reflexivity about the different perspectives of participant observers and an external observer is fundamental to the sociological discourse. The ranges of possible observations from different perspectives can be considered as second-order observations or equivalently as the specification of an uncertainty in the observations. This specification of an uncertainty provides us with an expectation. The expectation can be provided with (one or more) values by observations. The significance of observations can be tested when the expectations are properly specified. Value: The expectations (second-order observations) are structured and therefore systemic attributes to the discourse. However, the metaphor of a (meta-)biological observer has disturbed the translation of social systems theory into sociological discourse. Different discourses specify other expectations about possible observations. By specifying second-order observations as expectations, social systems theory.

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Guo, Lei active 21st century. « The political economy of U.S. alternative press : case studies of The nation and The Texas observer ». Thesis, 2010. http://hdl.handle.net/2152/ETD-UT-2010-05-1277.

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Throughout the history, U.S. alternative press has published against the grain of mainstream media and politics and on tight budgets. In fact, it remains the political economic dilemma for any critical media project that the financial resources it needs are in the same capitalism society it criticizes. Using a political economy approach, this thesis examined how political economic factors including ownership models, means of support and the government role influence the balance between the editorial goals and business performance of the two alternative or independent publications: The Nation, a privately-owned newsmagazine providing critical opinions and investigative journalism on nationwide issues, and The Texas Observer, a 501(c) (3) nonprofit biweekly covering stories ignored by the mainstream press in the state of Texas. Through in-depth interviews with staffers of the two publications and primary and second sources analysis, this thesis demonstrates the tension between editorial ideals and financial needs that are affected by several political economic factors. It also shows that both alternative papers are committed to democratic altruism and watchdog journalism whenever they deal with political economic pressures.
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Min, InCheol. « The alternative press and its readers producers' perceptions of their readers and the readership survey of the Texas Observer / ». 2002. http://wwwlib.umi.com/cr/utexas/fullcit?p3099498.

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« Shifts in Attitude Towards Disability Observed Through Seven German Films ». Master's thesis, 2010. http://hdl.handle.net/2286/R.I.8722.

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abstract: Disability is a label accompanied by a multitude of misconceptions and stereotypes. During various periods in Germany, attitudes towards disability have ranged from disgust and fear, to acceptance and inclusion. Being disabled in Germany once meant certain isolation; at the hands of the Nazi regime, it was met with almost certain premature death. Since those darker days of Germany's history, the country has become one that now affords its disabled citizens with the same rights as the non-disabled population and seeks to create a barrier-free environment. This study examines these perceptions of disability in Germany from the 1920s through the first decade of the 21st century. In order to accomplish this goal, cinema is used to provide insights into contemporaneous ideas about disability. By drawing upon analyses of six films that span the course of nearly 80 years, careful examination of disability portrayals reveal philosophical shifts in how the German people interpret disability. When analyzing these films, aspects of physical and mental disability are brought to the surface and discussed in terms of their sociopolitical and philosophical implications. To provide a social and cultural framework that gives significance to the changes in these cinematic roles, a historical survey of the German disability rights movement is folded into the discussion. The films explored in this study serve as culturally important visual aids that illustrate positive changes for the disabled living in Germany. Although not directly influencing cinematic portrayals of disability, the German disability rights movement that arose in the postwar period shaped ideas about disability and allowed disabled Germans to be accepted and included in society. With these rights now available disabled Germans are able to lead a self-determined life and portray themselves as equals.
Dissertation/Thesis
M.A. German 2010

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Thèses sur le sujet « Observer studies »

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