1,029 research outputs found
The great good place : coworking como espaço para aprender design uma framework exploratória
Abstract : In this paper we explore a conceptual framework based on
three lines of thinking/work from Patrick Cohendet
(Underground/Middleground/Upperground), Ray Oldenburg (The Great
Good Place), and Fred Garneti (Heutagogy or Self-determined Learning).
To demonstrate the relevance and feasibility of our proposed concept, we
review the key factors and definitions of these authors and their
work. Although not a theoretical framework, the present
paper aims to help us map a part of our research work within the context
of the Doctoral Programme in Design at IADE / Universidade Europeia,
which triangulates Coworking, Design Learning, and Heutagogy or selfdetermined
modes of learning. Ultimately, the aim is to generate
new evidence on how such a model of Coworking Design Learning can
benefit and betier suit contemporary Design learners.Neste artigo, exploramos uma estrutura conceptual baseada
em três linhas de pensamento dos autores Patrick Cohendet
(Underground / Middleground / Upperground), Ray Oldenburg (The Great
Good Place) e Fred Garneti (Heutagogy or Self-determined Learning).
Para demonstrar a relevância e a viabilidade da nossa proposta
conceptual, revisitamos os principais fatores e definições destes autores e
dos seus trabalhos. Embora não constitua uma framework teórica, o
presente trabalho tem como objetivo ajudar a mapear parte do nosso
trabalho de pesquisa no contexto do Programa de Doutoramento em
Design do IADE / Universidade Europeia, que triangula Coworking,
Aprendizagem de Design e Heutagogia ou modos autodeterminados de
aprendizagem. Em última instância, o objetivo é tentar produzir novas
evidências sobre como um modelo de aprendizagem de Design baseado
em espaços de Coworking pode beneficiar e adequar-se melhor aos
actuais alunos de Design.info:eu-repo/semantics/publishedVersio
Markov-switching models : empirical applications using classical and Bayesian inference
In this thesis, we present three empirical applications on finance and macroeconomics. The general modeling framework in all chapters is based on extensions of the Markov-switching model. And the statistical methodology is divided into two distinct areas; Classical and Bayesian inference.1 In the first one, we test for the presence of duration dependence in the Brazilian business cycle. The main results indicated that as the recession ages, the probability of a transition into an expansion increases (positive duration dependence in recessions). On the other hand, as the expansions ages, the probability of a transition into a recession decreases (negative duration dependence in expansions). In the second paper, we extend the research concerned with the evaluation of alternative volatility modeling and forecasting methods for Bitcoin log-returns. The in-sample estimates suggest evidence of long memory in the data series. When performing one-day ahead Value-at-Risk (VaR), our results outperform all standard single-regime GARCH models considered in the study. Finally, in the third paper, we capture different regimes in Bitcoin volatility returns and test the mean-reversion hypothesis for multi-period returns. In general, we found evidence of mean-aversion for different holding returns. We also confirmed this result for alternative specifications and also carrying the analysis for sub-sample periods
Mitigating the choice of the duration in DDMS models through a parametric link
One of the most important hyper-parameters in duration-dependent
Markov-switching (DDMS) models is the duration of the hidden states. Because
there is currently no procedure for estimating this duration or testing whether
a given duration is appropriate for a given data set, an ad hoc duration choice
must be heuristically justified. This is typically a difficult task and is
likely the most delicate point of the modeling procedure, allowing for
criticism and ultimately hindering the use of DDMS models. In this paper, we
propose and examine a methodology that mitigates the choice of duration in DDMS
models when forecasting is the goal. The idea is to use a parametric link
instead of the usual fixed link when calculating transition probabilities. As a
result, the model becomes more flexible and any potentially incorrect duration
choice (i.e., misspecification) is compensated by the parameter in the link,
yielding a likelihood and transition probabilities very close to the true ones
while, at the same time, improving forecasting accuracy under misspecification.
We evaluate the proposed approach in Monte Carlo simulations and using real
data applications. Results indicate that the parametric link model outperforms
the benchmark logit model, both in terms of in-sample estimation and
out-of-sample forecasting, for both well-specified and misspecified duration
values
Mitigating the choice of the duration in DDMS models through a parametric link
Um dos hiperparâmetros mais importantes em modelos de mudança de regime Markoviana e duração dependente (DDMS) é a duração dos regimes. Uma vez que não existe nenhum procedimento para estimar ou testar uma dada duração para um determinado conjunto de dados, geralmente uma escolha ad hoc deve ser heuristicamente justificada. Esta é uma tarefa tipicamente difÃcil e é provavelmente o ponto mais delicado da modelagem via modelos DDMS, sendo motivo de crÃticas, dificultando a sua aplicação. Neste trabalho, propomos e estudamos uma metodologia que atenua a escolha da duração nos modelos DDMS quando o foco é a previsão. A proposta é a utilização de um link paramétrico em vez do habitual link fixo ao calcular as probabilidades de transição. Como resultado, o modelo torna-se mais flexÃvel e escolhas do parâmetro de duração potencialmente incorretas (ou seja, erro de especificação) é compensada pelo parâmetro no link, produzindo probabilidades de transição próximas das verdadeiras e, ao mesmo tempo, melhorando a precisão da previsão no contexto de erro de especificação. A abordagem proposta é avaliada através de simulações de Monte Carlo e uma aplicação com dados reais é apresentada. Os resultados indicam que o modelo de link paramétrico supera o modelo logit, tanto em termos de previsões dentro da amostra quanto fora da amostra, tanto para valores de duração corretamente especificados como para valores de duração mal especificados.One of the most important hyper-parameters in duration-dependent Markov-switching (DDMS) models is the duration of the hidden states. Because there is currently no procedure for estimating this duration or testing whether a given duration is appropriate for a given data set, an ad hoc duration choice must be heuristically justified. This is typically a difficult task and is likely the most delicate point of the modeling procedure, allowing for criticism and ultimately hindering the use of DDMS models. In this work, we propose and examine a methodology that mitigates the choice of duration in DDMS models when forecasting is the goal. The idea is to use a parametric link instead of the usual fixed link when calculating transition probabilities. As a result, the model becomes more flexible and any potentially incorrect duration choice (i.e., misspecification) is compensated by the parameter in the link, yielding a likelihood and transition probabilities very close to the true ones while, at the same time, improving forecasting accuracy under misspecification. We evaluate the proposed approach in Monte Carlo simulations and using real data applications. Results indicate that the parametric link model outperforms the benchmark logit model, both in terms of in-sample estimation and out-ofsample forecasting, for both well-specified and misspecified duration values
Evidências de Bull e Bear Market no Ãndice Bovespa: uma aplicação de modelos de regime markoviano e duration dependence
Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro Sócio Econômico, Programa de Pós-Graduação em Economia, Florianópolis, 2013.O objetivo deste trabalho é identificar tendências de alta e de baixa no Ãndice Bovespa através de modelos de mudança de regime markoviano que incorporam dependência de duração. Conforme evidenciado pela literatura,os resultados mostraram um regime de retorno positivo e baixa volatilidade e outro com alta volatilidade e retorno negativo. Nestes modelos a probabilidade de transição não é só função do regime atual como também do número de perÃodos em que o processo se encontra em determinado estado. A parametrização proposta revelou que a probabilidade de troca de regime diminui com a persistência do mercado de alta e de baixa. A análise das probabilidades suavizadas destaca que as especificações captaram os principais episódios de instabilidade na bolsa brasileira.Por fim, os modelos propostos são usados na construção de uma estratégia de investimento. Abstract : This study proposes to identify Bull and Bear Market for the Brazilianstock market using a markov switching model that incorporates durationdependence. Following the existing literature, the model sorts returnsinto a high return stable state and a low return volatile state, whichare labeled as Bull and Bear Market. In these models the transitionprobabilities are functions of both the inferred current state and alsothe number of periods that the process has been in that state. The parameterizationshowed that the probability of switching out of the statesdeclines with duration in that state. The smoothed probabilities highlightedthe major instabilities phases at Brazilian stock market. Finally,the proposed models are used in order to develop an investment strategy
O impacto de primeiro ano de tratamento com dornase alfa nos parâmetros clÃnicos de pacientes com fibrose cÃstica: estudo multicêntrico brasileiro
OBJECTIVE:To describe the clinical impact of the first year treatment with dornase alfa, according to age groups, in a cohort of Brazilian Cystic Fibrosis (CF) patients.METHODS:The data on 152 eligible patients, from 16 CF reference centers, that answered the medical questionnaires and performed laboratory tests at baseline (T0), and at six (T2) and 12 (T4) months after dornase alfa initiation, were analyzed. Three age groups were assessed: six to 11, 12 to 13, and >14 years. Pulmonary tests, airway microbiology, emergency room visits, hospitalizations, emergency and routine treatments were evaluated. Student's t-test, chi-square test and analysis of variance were used when appropriated.RESULTS:Routine treatments were based on respiratory physical therapy, regular exercises, pancreatic enzymes, vitamins, bronchodilators, corticosteroids, and antibiotics. In the six months prior the study (T0 phase), hospitalizations for pulmonary exacerbations occurred in 38.0, 10.0 and 61.4% in the three age groups, respectively. After one year of intervention, there was a significant reduction in the number of emergency room visits in the six to 11 years group. There were no significant changes in forced expiratory volume in one second (VEF1), in forced vital capacity (FVC), in oxygen saturation (SpO2), and in Tiffenau index for all age groups. A significant improvement in Shwachman-Kulczychi score was observed in the older group. In the last six months of therapy, chronic or intermittent colonization by P. aeruginosa was detected in 75.0, 71.4 and 62.5% of the studied groups, respectively, while S. aureus colonization was identified in 68.6, 66.6 and 41.9% of the cases.CONCLUSIONS:The treatment with dornase alfa promoted the maintenance of pulmonary function parameters and was associated with a significant reduction of emergency room visits due to pulmonary exacerbations in the six to 11 years age group, with better clinical scores in the >14 age group, one year after the intervention.OBJETIVO:Relatar el impacto clÃnico del primer año de tratamiento con dornasa alfa conforme a la franja de edad, en una cohorte de pacientes brasileños con fibrosis quÃstica (FC).MÉTODOS:El presente estudio analizó datos de 152 pacientes elegibles, de 16 centros de referencia para FC, los que contestaron a los cuestionarios clÃnicos y realizaron pruebas laboratoriales, al inicio del tratamiento con la dornasa alfa (T0) y después de 6 (T2) y 12 (T4) meses de la intervención. Se analizaron 3 grupos etarios: 6-11, 12-13 e >14 años de edad. Se evaluaron las pruebas pulmonares, la microbiologÃa de vÃas aéreas, las atenciones de emergencia, hospitalizaciones y tratamientos emergenciales y de rutina. Las estadÃsticas descriptivas, pruebas t y chi-cuadrado y ANOVA fueron usadas cuando pertinentes.RESULTADOS:El tratamiento regular se basó en la fisioterapia respiratoria, ejercicios regulares, encimas pancreáticas, vitaminas, broncodilatadores, corticosteroides y antibióticos. En los 6 meses anteriores al estudio (fase T0), las hospitalizaciones por exacerbación pulmonar ocurrieron en 38, 10 y 61,4%, respectivamente, para las tres franjas de edad analizadas. En el grupo 6-11 años, hubo reducción significativa de atenciones de emergencia después de 1 año de tratamiento. No hubo modificaciones significativas de volumen espiratorio forzado en el 1er segundo (VEF1), capacidad vital forzada (CVF), saturación de oxÃgeno (SpO)2 e Ãndice de Tiffeneau, en todos grupos. El escore de Schwachman-Kulczychi mejoró significativamente en el grupo de más edad. Los últimos 6 meses de tratamiento, la colonización crónica o intermitente por P. aeruginosa fue detectada en el 75, 71,4 y 62,5%, respectivamente, mientras que por S. aureus ocurrió en 68,6, 66,6 y 41,9% de los casos en cada grupo de edad.CONCLUSIONES:La intervención con dornasa alfa resultó en mantenimiento de los parámetros pulmonares y fue asociada a la reducción significativa de visitas a la emergencia por exacerbación pulmonar en el grupo de 6 a 11 años de edad, con mejora del escore clÃnico en el grupo >14 años de edad, al final de un año de estudio.OBJETIVO:Relatar o impacto clÃnico do primeiro ano de tratamento com dornase alfa de acordo com a faixa etária, numa coorte de pacientes brasileiros com fibrose cÃstica (FC).MÉTODOS:O presente estudo analisou dados de 152 pacientes elegÃveis, de 16 centros de referência para FC, os quais responderam aos questionários clÃnicos e realizaram testes laboratoriais, ao inÃcio do tratamento com dornase alfa (T0) e após seis (T2) e 12 (T4) meses da intervenção. Analisaram-se três grupos etários: seis a 11, 12 a 13 e >14 anos de idade. Avaliaram-se os testes pulmonares, a microbiologia de vias aéreas, os atendimentos de emergência, as hospitalizações e os tratamentos emergenciais e rotineiros. O teste t de Student, o qui-quadrado e a análise de variância foram usados quando pertinentes.RESULTADOS:O tratamento baseou-se em fisioterapia respiratória, exercÃcios regulares, enzimas pancreáticas, vitaminas, broncodilatadores, corticosteroides e antibióticos. Nos seis meses anteriores ao estudo (fase T0), as hospitalizações por exacerbação pulmonar ocorreram em 38,0, 10,0 e 61,4%, respectivamente para as três faixas etárias analisadas. No grupo de seis a 11 anos, houve redução significativa de atendimentos de emergência após um ano de tratamento. Não houve modificações significativas de volume expiratório forçado no primeiro segundo (VEF1), capacidade vital forçada (CVF), saturação de oxigênio (SpO)2 e Ãndice de Tiffeneau em todos os grupos. O escore de Shwachman-Kulczychi melhorou significativamente no grupo de mais idade. Nos últimos seis meses de tratamento, a colonização crônica ou intermitente por P.aeruginosa foi detectada em 75,0, 71,4 e 62,5%, respectivamente, enquanto a colonização por S.aureus ocorreu em 68,6, 66,6 e 41,9% dos casos em cada grupo etário.CONCLUSÕES:A intervenção com dornase alfa resultou em manutenção dos parâmetros pulmonares e associou-se à redução significativa de visitas à emergência por exacerbação pulmonar no grupo de seis a 11 anos de idade, com melhora do escore clÃnico no grupo >14 anos de idade ao final de um ano de estudo.Universidade Federal de São Paulo (UNIFESP), Escola Paulista de Medicina (EPM)Universidade Federal do Rio Grande do Sul Faculdade de MedicinaSecretaria da Saúde da Bahia Hospital Especializado Octávio MangabeiraUniversidade de São Paulo Faculdade de Medicina Hospital das ClÃnicasHospital de Base do Distrito FederalUNIFESP, EPMSciEL
Interactive tabletops for architectural visualization: combining stereoscopy and touch interfaces for cultural heritage
This paper presents an interactive apparatus to didactically explore Alberti's treatise on architecture, De re aedificatoria, as generative design systems, namely shape grammars. This apparatus allows users to interactively explore such architectonical knowledge in both appealing and informal ways, by enabling
them to visualize and manipulate in real-time different design solutions. The authors identify the difficulties on encoding the architectural knowledge of a parametric design model into an interactive apparatus to be used by laypeople.
At last, the authors discuss the results of a survey conducted to users that interacted with the prototype in order to assess its ability to communicate the knowledge of an architectural language.Fundação para a Ciência e a Tecnologia (FCT)Escola de Arquitectura da Universidade do MinhoThis work was partially supported by the Portuguese Foundation for Science and Technology (FCT): doctoral grants SFRH/BD/69910/2010, SFRH/BD/88040/2012 and SFRH/BD/91372/2012, and projects MIVis PTDC/EIA-EIA/104031/2008, Alberti Digital PTDC/AUR-AQI/108274/2008, TECTON-3D PTDC/EEI-SII/3154/2012 and Pest OE/EEI/LA0021/2013
Numerical simulation of the hydrodynamic in the Curimataú estuary, RN Brazil
The Curimataú River estuary is a shallow partially mixed (type 2) tropical estuary, located in the Rio Grande do Norte (RN) state, northeast Brazilian coast (lat. 06o18’S); the main system is composed by three rivers: Curimataú, Cunhaú and Guaratuba. The numerical model Delft3D-Flow was used to study hydrodynamic features of the estuary. The model predictions were evaluated using the Skill parameter based in the comparison of the theoretical solutions with observations of hourly values of tidal heights, currents and salinity at an anchor station located at the cell (M=279; N=323). The applied computational grid is curvilinear with around 6,000 horizontal wet points, including the inner shelf. Open boundary conditions was obtained from the analysis of 2.7 years of hourly tidal heights, recorded at Natal harbor, and the inner boundaries conditions were controlled by freshwater input into the three main rivers. Initial conditions of hydrographic properties were uniform in the previous simulations and, only the temperature was set to a constant value in whole simulation. The steady-state of the fields of velocity and thermohaline properties was reached after almost four weeks of simulation of the baroclinic mode. The best fit between the model and the observations was for the semidiurnal spring tide oscillation with a Skill=0.98; for the velocities and salinities simulations during this tidal condition the best mean Skills values were 0.82 and 0.94, respectively
The use of eye tracking glasses in basketball shooting : a systematic review
Sports performance is related to cognitive processes that precede the motor task to be developed. In this
way, the coupling between visual information and motor behavior has a major importance in filtering the visual
information, necessary to the accomplishment of the motor task to be executed, ignoring ‘accessory’ stimuli. In
this field, this essay has the goal of achieving a systematic review about past studies in the context of basketball
shooting. We bring to you some evidence that support the applicability and efficiency of Eye Tracking Glasses
systems in the analysis of visual attention in basketball shooting, emphasizing the concept of Quiet Eye,
interconnected with anxiety and occlusion of vision. The results of the studies demonstrate the importance of the
use of Eye Tracking Glasses for the evaluation/intervention in the process of visual attention training related to
efficiency in shooting.info:eu-repo/semantics/publishedVersio
Influence of nitrogen content on the structural, mechanical and electrical properties of TiN thin films
This paper reports on the preparation of TiNx thin films by d.c. reactive magnetron sputtering. The coating thickness ranged from 1.7 to
4.2 Am and the nitrogen content varied between 0 and 55 at.%. X-Ray diffraction showed the development of the hexagonal a-Ti phase, with
strong [002] orientation for low nitrogen contents, where the N atoms fit into octahedral sites in the Ti lattice as the amount of nitrogen is
increased. For nitrogen contents of 20 and 30 at.%, the q-Ti2N phase appears with [200] orientation. With further increasing the nitrogen
content, the y-TiN phase becomes dominant. The electrical resistivity of the different compositions reproduces this phase behavior. The
hardness of the samples varied from approximately 8 GPa for pure titanium up to 27 GPa for a nitrogen content of 30 at.%, followed by a
slight decrease at the highest contents. A similar increase of stresses with nitrogen is observed. Structure and composition with the
consequent changes in crystalline phases and the lattice distortion were found to be crucial in the evolution of the mechanical properties
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