977 resultados para analytical approaches
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Ecological work carried out on the Antarctic and Magellan shelves since the first IBMANT conference held at the UMAG, Punta Arenas in 1997 is summarized to identify areas where progress has been made and others, where impor- tant gaps have remained in understanding past and present interaction between the Antarctic and the southern tip of South America. This information is complementary to a review on shallow-water work along the Scotia Arc (Barnes, 2005) and recent work done in the deep sea (Brandt and Hilbig, 2004). While principally referring to shipboard work in deeper water, above all during the recent international EASIZ and LAMPOS campaigns, relevant work from shore stations is also included. Six years after the first IBMANT symposium, significant progress has been made along the latitudinal gradient from the Magellan region to the high Antarctic in the fields of biodiversity, biogeography and community structure, life strategies and adaptations, the role of disturbance and its significance for biodiversity, and trophic coupling of the benthic realm with the water column and sea ice. A better understanding has developed of the role of evolutionary and ecological factors in shaping past and present-day environmental conditions, species composition and distribution, and ecosystem functioning. Furthermore, the science community engaged in unravelling Antarctic-Magellan interactions has advanced in methodological aspects such as new analytical approaches for comparing biodiversity derived from visual methods, growth and age determination, trophic modelling using stable isotope ratios, and molecular approaches for taxonomic and phylogenetic purposes. At the same time, much effort has been invested to complement the species inventory of the two adjacent regions. However, much work remains to be done to fill the numerous gaps. Some perspectives are outlined in this review, and sug- gestions are made where particular emphasis should be placed in future work, much of which will be developed in the frame of SCAR's EBA (Evolution and Biodiversity in the Antarctic) programme.
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Thesis (Ph.D.)--University of Washington, 2016-06
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Este estudo tem como objetivo avaliar a representação e discurso dos personagens homossexuais da teledramaturgia brasileira e sua potencial relação com as demandas da comunidade homossexual na sua luta por maior tolerância e emancipação. A metodologia inclui dois enfoques analíticos: o primeiro centra-se no campo da produção, a partir dos pressupostos da Análise do Discurso e dos Estudos Queer, verificando os aspectos textuais do discurso e da representação dos personagens gays das telenovelas. O segundo enfoque centra-se no campo da circulação e consumo, mediante os pressupostos dos Estudos de Recepção, a fim de avaliar como os receptores realizam a apropriação do discurso e representação homossexual da telenovela. Esse segundo enfoque conta com um instrumento quantitativo e uma entrevista qualitativa semidirigida, aplicados a uma amostra de 402 participantes, hétero e homossexuais, a maioria jovens estudantes de graduação em Belo Horizonte, MG. Quanto às análises discursivas, os resultados demonstram uma mudança no padrão de representação dos personagens homossexuais, deslocando-se do padrão heteronormativo para uma representação mais humanizada, seguindo o momento histórico de maturidade política da sociedade e a aprovação de marcos legais favoráveis aos sujeitos homossexuais. Quanto aos estudos de recepção, os resultados confirmam o potencial pedagógico da telenovela em ampliar a discussão sobre a questão homoafetiva; auxiliar o sujeito homossexual em aceitar sua identidade sexual e encorajá-lo a assumir sua orientação sexual.
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Data visualization algorithms and feature selection techniques are both widely used in bioinformatics but as distinct analytical approaches. Until now there has been no method of measuring feature saliency while training a data visualization model. We derive a generative topographic mapping (GTM) based data visualization approach which estimates feature saliency simultaneously with the training of the visualization model. The approach not only provides a better projection by modeling irrelevant features with a separate noise model but also gives feature saliency values which help the user to assess the significance of each feature. We compare the quality of projection obtained using the new approach with the projections from traditional GTM and self-organizing maps (SOM) algorithms. The results obtained on a synthetic and a real-life chemoinformatics dataset demonstrate that the proposed approach successfully identifies feature significance and provides coherent (compact) projections. © 2006 IEEE.
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In this chapter, the authors use an EGARCH-ECM to estimate the pass-through effects of Foreign Exchange (FX) rate changes and changes in producers' prices for 20 U.K. export sectors. The long-run adjustments of export prices to FX rate changes and changes in producers' prices are within the range of -1.02% (for the Textiles sector) and -17.22% (for the Meat sector). The contemporaneous Pricing-To-Market (PTM) coefficients are within the range of -72.84% (for the Fuels sector) and -8.05% (for the Textiles sector). Short-run FX rate pass-through is not complete even after several months. Rolling EGARCH-ECMs show that the short and long-run effects of changes in FX rate and producers' prices vary substantially, as do asymmetry and volatility estimates before equilibrium is achieved.
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Within the contemporary business milieu, the discipline of selling and sales management has taken on a more prominent role in recent years. Myriad factors have contributed to the rise of interest in sales including globalization, technology, more sophisticated analytical approaches and new opportunities for co-creation of value between organizations and their customers. Over the past three decades, seven faculty consortia in sales have served as milestones to document the progress 2of the field, particularly the evolution of academic research. This article provides key takeaways from the most recent American Marketing Association (AMA) Faculty Consortium in Selling and Sales Management, which had the overarching goal of fostering new opportunities for building intercontinental research teams to effectively address the substantive issues for the future of the field. © 2014 Pi Sigma Epsilon National Educational Foundation.
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The research goal was to document differences in the epidemiology of prostate cancer among multicultural men [non-Hispanic White (NHW), Hispanic (H), non-Hispanic Black (NHB)], and Black subgroups, particularly among NHB subgroups [US-born (USB) and Caribbean-born (CBB)]. Study findings will be useful in supporting further research into Black subgroups. Aim 1 explored changes over time in reported prostate cancer prevalence, by race/ethnicity and by birthplace (within the Black subgroups). Aim 2 investigated relationships between observed and latent variables. The analytical approaches included confirmatory factor analysis (CFA for measurement models) and structural equation modeling (SEM for regression models). National Center for Health Statistics, National Health Interview Survey (NHIS) data from 1999–2008 were used. The study sample included men aged 18 and older, grouped by race/ethnicity. Among the CBB group, survey respondents were limited to the English-speaking Caribbean. Prostate cancer prevalence, by race showed a higher trend among NHB men than NHW men overall, however differences over time were not significant. CBB men reported a higher proportion of prostate cancer among cancers diagnosed than USB men overall. Due to small sample sizes, stable prostate cancer prevalence trends could not be assessed over time nor could trends in the receipt of a PSA exam among NHB men when stratified by birthplace. USB and CBB men differ significantly in their screening behavior. The effect of SES on PSA screening adjusted for risk factors was statistically significant while latent variable lifestyle was not. Among risk factors, family history of cancer exhibited a consistent positive effect on PSA screening for both USB and CBB men. Among the CBB men, the number of years lived in the US did not significantly affect PSA screening behavior. When NHB men are stratified by birthplace, CBB men had a higher overall prevalence of prostate cancer diagnoses than USB men although not statistically significant. USB men were 2 to 3 times more likely to have had a PSA exam compared to CBB men, but among CBB men birthplace did not make a significant difference in screening behavior. Latent variable SES, but not lifestyle, significantly affected the likelihood of a PSA exam.
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The focus of this work is to develop and employ numerical methods that provide characterization of granular microstructures, dynamic fragmentation of brittle materials, and dynamic fracture of three-dimensional bodies.
We first propose the fabric tensor formalism to describe the structure and evolution of lithium-ion electrode microstructure during the calendaring process. Fabric tensors are directional measures of particulate assemblies based on inter-particle connectivity, relating to the structural and transport properties of the electrode. Applying this technique to X-ray computed tomography of cathode microstructure, we show that fabric tensors capture the evolution of the inter-particle contact distribution and are therefore good measures for the internal state of and electronic transport within the electrode.
We then shift focus to the development and analysis of fracture models within finite element simulations. A difficult problem to characterize in the realm of fracture modeling is that of fragmentation, wherein brittle materials subjected to a uniform tensile loading break apart into a large number of smaller pieces. We explore the effect of numerical precision in the results of dynamic fragmentation simulations using the cohesive element approach on a one-dimensional domain. By introducing random and non-random field variations, we discern that round-off error plays a significant role in establishing a mesh-convergent solution for uniform fragmentation problems. Further, by using differing magnitudes of randomized material properties and mesh discretizations, we find that employing randomness can improve convergence behavior and provide a computational savings.
The Thick Level-Set model is implemented to describe brittle media undergoing dynamic fragmentation as an alternative to the cohesive element approach. This non-local damage model features a level-set function that defines the extent and severity of degradation and uses a length scale to limit the damage gradient. In terms of energy dissipated by fracture and mean fragment size, we find that the proposed model reproduces the rate-dependent observations of analytical approaches, cohesive element simulations, and experimental studies.
Lastly, the Thick Level-Set model is implemented in three dimensions to describe the dynamic failure of brittle media, such as the active material particles in the battery cathode during manufacturing. The proposed model matches expected behavior from physical experiments, analytical approaches, and numerical models, and mesh convergence is established. We find that the use of an asymmetrical damage model to represent tensile damage is important to producing the expected results for brittle fracture problems.
The impact of this work is that designers of lithium-ion battery components can employ the numerical methods presented herein to analyze the evolving electrode microstructure during manufacturing, operational, and extraordinary loadings. This allows for enhanced designs and manufacturing methods that advance the state of battery technology. Further, these numerical tools have applicability in a broad range of fields, from geotechnical analysis to ice-sheet modeling to armor design to hydraulic fracturing.
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The presence of harmful algal blooms (HAB) is a growing concern in aquatic environments. Among HAB organisms, cyanobacteria are of special concern because they have been reported worldwide to cause environmental and human health problem through contamination of drinking water. Although several analytical approaches have been applied to monitoring cyanobacteria toxins, conventional methods are costly and time-consuming so that analyses take weeks for field sampling and subsequent lab analysis. Capillary electrophoresis (CE) becomes a particularly suitable analytical separation method that can couple very small samples and rapid separations to a wide range of selective and sensitive detection techniques. This paper demonstrates a method for rapid separation and identification of four microcystin variants commonly found in aquatic environments. CE coupled to UV and electrospray ionization time-of-flight mass spectrometry (ESI-TOF) procedures were developed. All four analytes were separated within 6 minutes. The ESI-TOF experiment provides accurate molecular information, which further identifies analytes.
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The goal of this work is to present an efficient CAD-based adjoint process chain for calculating parametric sensitivities (derivatives of the objective function with respect to the CAD parameters) in timescales acceptable for industrial design processes. The idea is based on linking parametric design velocities (geometric sensitivities computed from the CAD model) with adjoint surface sensitivities. A CAD-based design velocity computation method has been implemented based on distances between discrete representations of perturbed geometries. This approach differs from other methods due to the fact that it works with existing commercial CAD packages (unlike most analytical approaches) and it can cope with the changes in CAD model topology and face labeling. Use of the proposed method allows computation of parametric sensitivities using adjoint data at a computational cost which scales with the number of objective functions being considered, while it is essentially independent of the number of design variables. The gradient computation is demonstrated on test cases for a Nozzle Guide Vane (NGV) model and a Turbine Rotor Blade model. The results are validated against finite difference values and good agreement is shown. This gradient information can be passed to an optimization algorithm, which will use it to update the CAD model parameters.
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Increasing research has highlighted the effects of changing climates on the occurrence and prevalence of toxigenic Aspergillus species producing aflatoxins. There is concern of the toxicological effects to human health and animal productivity following acute and chronic exposure that may affect the future ability to provide safe and sufficient food globally. Considerable research has focused on the detection of these toxins, based on the physicochemical and biochemical properties of the aflatoxin compounds, in agricultural products for human and animal consumption. As improvements in food security continue more regulations for acceptable levels of aflatoxins have arisen globally; the most stringent in Europe. These regulations are important for developing countries as aflatoxin occurrence is high significantly effecting international trade and the economy. In developed countries analytical approaches have become highly sophisticated, capable of attaining results with high precision and accuracy, suitable for regulatory laboratories. Regrettably, many countries that are affected by aflatoxin contamination do not have resources for high tech HPLC and MS instrumentation and require more affordable, yet robust equally accurate alternatives that may be used by producers, processors and traders in emerging economies. It is especially important that those companies wishing to exploit the opportunities offered by lucrative but highly regulated markets in the developed world, have access to analytical methods that will ensure that their exports meet their customers quality and safety requirements.
This work evaluates the ToxiMet system as an alternative approach to UPLC–MS/MS for the detection and determination of aflatoxins relative to current European regulatory standards. Four commodities: rice grain, maize cracked and flour, peanut paste and dried distillers grains were analysed for natural aflatoxin contamination. For B1 and total aflatoxins determination the qualitative correlation, above or below the regulatory limit, was good for all commodities with the exception of the dried distillers grain samples for B1 for which no calibration existed. For B1 the quantitative R2 correlations were 0.92, 0.92, 0.88 (<250 μg/kg) and 0.7 for rice, maize, peanuts and dried distillers grain samples respectively whereas for total aflatoxins the quantitative correlation was 0.92, 0.94, 0.88 and 0.91. The ToxiMet system could be used as an alternative for aflatoxin analysis for current legislation but some consideration should be given to aflatoxin M1 regulatory levels for these commodities considering the high levels detected in this study especially for maize and peanuts
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Cette thèse tente de comprendre l’impact des restructurations des entreprises multinationales sur les stratégies syndicales. Les acteurs syndicaux locaux sont-ils déterminés par l’appartenance à des régimes nationaux et à des contingences organisationnelles ou peuvent-ils influencer des décisions objectives comme les restructurations ? Cette recherche s’insère dans une problématique large qui fait la jonction entre la mondialisation économique sur une base continentale, la réorganisation productive des entreprises multinationales et l’action syndicale. Au plan théorique, nous confrontons trois grandes approches analytiques, à savoir : le néo-institutionnalisme et les structures d’opportunités ; l’économie politique critique et la question du pouvoir syndical ; la géographie économique critique mettant de l’avant les contingences, l’encastrement et l’espace concurrentiel. Sur la base de ces trois familles, nous présentons un modèle d’analyse multidisciplinaire. Au plan méthodologique, cette thèse est structurée autour de quatre études de cas locales qui ont subi des menaces de restructurations. Cette collecte a été effectuée dans deux pays (la France et le Canada) et dans un secteur particulier (les équipementiers automobiles). Trois sources qualitatives forment le cœur empirique de cette thèse : des statistiques descriptives, des documents de sources secondaires et des entretiens semi-dirigés (44), principalement avec des acteurs syndicaux. L’analyse intra et inter régime national éclaire plusieurs aspects de la question des stratégies syndicales en contexte de restructurations. Les principales contributions de cette thèse touchent : 1. l’impact des facteurs relationnels et des ressources de pouvoir développées par les syndicats locaux sur les structures d’opportunités institutionnelles; 2. l’importance des aspects « cognitifs » et d’envisager le pouvoir de manière multi-niveaux; 3. l’importance de l’encastrement social et des dynamiques relationnelles entre syndicats et patronats; 4. l’influence de la concurrence internationale/nationale/régionale/locale dans le secteur des équipementiers automobiles; et 5. l’importance des arbitrages et des relations entre les acteurs de l’entreprise par rapport à la théorie de la contingence pour comprendre les marges structurelles des syndicats locaux. Notre recherche invite les acteurs sociaux à repenser leur action dans le cadre des restructurations. En particulier, les syndicats locaux se doivent d’explorer de nouveaux répertoires stratégiques pour répondre aux nombreux défis que posent le changement économique et les restructurations.
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As a teacher educator I consider myself an advocate for research-informed education, and strongly believe that it starts with one’s own critical self-reflection and analysis of one’s own teaching practice. Critical incident analysis is a pedagogical theory developed by Tripp (1993), whose analytical approaches allow reflection on teaching situations – ‘the critical incident’ – so that teachers can develop their professional judgments and practices. This article examines the concept of critical incident analysis through a teaching situation, with the aim of improving the teaching practice of students on teacher education programmes. I conclude that although critical incident analysis is a useful tool in navigating teaching practices, often challenges need to be addressed at much broader levels than the teaching context itself.
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Cette thèse tente de comprendre l’impact des restructurations des entreprises multinationales sur les stratégies syndicales. Les acteurs syndicaux locaux sont-ils déterminés par l’appartenance à des régimes nationaux et à des contingences organisationnelles ou peuvent-ils influencer des décisions objectives comme les restructurations ? Cette recherche s’insère dans une problématique large qui fait la jonction entre la mondialisation économique sur une base continentale, la réorganisation productive des entreprises multinationales et l’action syndicale. Au plan théorique, nous confrontons trois grandes approches analytiques, à savoir : le néo-institutionnalisme et les structures d’opportunités ; l’économie politique critique et la question du pouvoir syndical ; la géographie économique critique mettant de l’avant les contingences, l’encastrement et l’espace concurrentiel. Sur la base de ces trois familles, nous présentons un modèle d’analyse multidisciplinaire. Au plan méthodologique, cette thèse est structurée autour de quatre études de cas locales qui ont subi des menaces de restructurations. Cette collecte a été effectuée dans deux pays (la France et le Canada) et dans un secteur particulier (les équipementiers automobiles). Trois sources qualitatives forment le cœur empirique de cette thèse : des statistiques descriptives, des documents de sources secondaires et des entretiens semi-dirigés (44), principalement avec des acteurs syndicaux. L’analyse intra et inter régime national éclaire plusieurs aspects de la question des stratégies syndicales en contexte de restructurations. Les principales contributions de cette thèse touchent : 1. l’impact des facteurs relationnels et des ressources de pouvoir développées par les syndicats locaux sur les structures d’opportunités institutionnelles; 2. l’importance des aspects « cognitifs » et d’envisager le pouvoir de manière multi-niveaux; 3. l’importance de l’encastrement social et des dynamiques relationnelles entre syndicats et patronats; 4. l’influence de la concurrence internationale/nationale/régionale/locale dans le secteur des équipementiers automobiles; et 5. l’importance des arbitrages et des relations entre les acteurs de l’entreprise par rapport à la théorie de la contingence pour comprendre les marges structurelles des syndicats locaux. Notre recherche invite les acteurs sociaux à repenser leur action dans le cadre des restructurations. En particulier, les syndicats locaux se doivent d’explorer de nouveaux répertoires stratégiques pour répondre aux nombreux défis que posent le changement économique et les restructurations.