Effektiv lagerstyrning med AHP och tvådimensionell artikelklassificering : En fallstudie på Permobil AB, Timrå

Costs related to inventory are usually a significant amount of the company’s total assets. Despite this, companies in general don’t pay a lot of interest in it, even if the benefits from effective inventory are obvious when it comes to less tied up capital, increased customer satisfaction and better working environment. Permobil AB, Timrå is in an intense period when it comes to revenue and growth. The production unit is aiming for an increased output of 30 % in the next two years. To make this possible the company has to improve their way to distribute and handle material,The purpose of the study is to provide useful information and concrete proposals for action, so that the company can build a strategy for an effective and sustainable solution when it comes to inventory management. Alternative methods for making forecasts are suggested, in order to reach a more nuanced perception of different articles, and how they should be managed. Analytic Hierarchy Process (AHP) was used in order to give specially selected persons the chance to decide criteria for how the article should be valued. The criteria they agreed about were annual volume value, lead time, frequency rate and purchase price. The other method that was proposed was a two-dimensional model where annual volume value and frequency was the criteria that specified in which class an article should be placed. Both methods resulted in significant changes in comparison to the current solution. For the spare part inventory different forecast methods were tested and compared with the current solution. It turned out that the current forecast method performed worse than both moving average and exponential smoothing with trend. The small sample of ten random articles is not big enough to reject the current solution, but still the result is a reason enough, for the company to control the quality of the forecasts.

Propriedades Psicométricas da Bateria de Avaliação Frontal numa Amostra de Adultos da População Portuguesa

The Frontal Assessment Batery / A Bateria de Avaliação Frontal (FAB) é um teste neuropsicológico, constituído por seis subtestes, cujo objetivo é avaliar a disfunção executiva global, nomeadamente as funções relacionadas com o lobo frontal, tais como a concetualização, flexibilidade mental, programação motora, sensibilidade à interferência, controlo inibitório e autonomia ambiental frontal. De forma a contribuir para o avanço dos estudos normativos em Portugal, esta dissertação tem como objetivo avaliar as propriedades psicométricas da FAB, numa amostra de adultos da população portuguesa. O protocolo abrangeu a seguinte bateria de testes neuropsicológicos: Bateria de Avaliação Frontal, Figura Complexa de Rey, Matrizes Progressivas de Raven e Teste do Desenho do Relógio. A amostra deste estudo incluiu 376 indivíduos, 155 do sexo masculino e 221 do sexo feminino. Os resultados desta investigação sugerem que a pontuação da FAB é influenciada por algumas variáveis sociodemográficas, designadamente a idade, escolaridade, profissões e região. A análise correlacional mostrou que há apenas uma correlação positiva moderada entre a FAB e as Matrizes Progressivas de Raven. Apesar da consistência interna da FAB ser baixa, existe uma estabilidade temporal moderada. Ao finalizar, consideramos que a FAB reúne os requisitos para se apresentar como uma bateria útil e eficaz, demonstrando um grau razoável de estabilidade temporal, mas fraca consistência interna, sugerindo que a FAB não é indicada para amostra não clínica. / The Frontal Assessment Baterry (FAB) is a neuropsychological test, composed of six subtests, whose aim is to assess the overall executive dysfunction, namely functions related to the frontal lobe, such as conceptualization, mental flexibility, motor programming, sensitivity to interference, inhibitory control and environmental autonomy. In order to contribute to the advancement of normative studies in Portugal, this dissertation aim to evaluate the psychometric properties of the FAB, in an adult sample of the portuguese population. The protocol included the following battery of neuropsychological tests: Frontal Assessment Battery, Complex Figure of Rey, Raven's Progressive Matrices and Clock Drawing Test. The sample this study included 376 individuals, 155 male and 221 female. The results of this investigation suggest that FAB is influenced by some sociodemographic variables, namely age, education, profession and region. The correlational analysis showed that there is only a moderate positive correlation between the FAB and the Raven Progressive Matrices. However, also they found low positive correlations between the FAB and the Complex Figure of Rey, and Clock Drawing Test. Although the FAB has a low internal consistency, there is a moderate temporal stability. Finally, we consider that the FAB gathers the requirements to present itself as a useful and effective battery, demonstrating a reasonable degree of temporal stability, but weaker internal consistency, suggesting that the FAB is not indicate for non-clinical sample.

Propriedades Psicométricas do Teste Stroop numa Amostra de Adultos da População Portuguesa: estudo preliminar

Objetivos: O presente estudo insere-se no Projeto - Estudos Normativos de Instrumentos Neuropsicologicos (ENIN) e tem por objetivo analisar as propriedades psicométricas do Teste Stroop, fornecendo dados normativos de uma amostra da População Portuguesa. Métodos: Selecionámos e inquirimos 671 sujeitos. As variáveis independentes estudadas foram idade, sexo, escolaridade e profissão. Foram utilizados vários testes neste estudo, contribuindo para a obtenção de validade convergente: Bateria de Avaliação Frontal-FAB, Figura Complexa de Rey-Osterrieth e Teste do Relógio. Foram estudadas a consistência interna e a estabilidade temporal do Teste Stroop. Resultados: A nossa amostra ficou constituída por 310 sujeitos (46,2%) do sexo masculino e 361 (53,8%) do sexo feminino, com idades compreendidas entre os 18 e 100 anos (M = 41,12; DP = 20,85). No que se refere ao nível de escolaridade (M = 5,71; DP = 1,45), este variou entre o 1º Ciclo do Ensino Básico e o Ensino Superior. As profissões, exercidas inseriram-se maioritariamente na categoria das profissões intelectuais (N = 281; 84,9%). Relativamente às variáveis sociodemográficas, verificámos que a idade, sexo, escolaridade e profissão influenciam nas provas de Leitura e Nomeação de Cor do Teste Stroop. No que diz respeito à validade convergente, observámos que a prova de Nomeação de Cor apresentou correlações positivas fracas com o FAB, Figura Complexa de Rey-Cópia (FCR-Cópia) e Teste do Relógio, e correlações positivas moderadas com a prova de Leitura. A consistência interna do Teste Stroop apresentou uma elevada confiabilidade (α = 0,99). A correlação teste-reteste apenas se mostrou significativa para a prova de Nomeação de Cor. Conclusão: Este estudo mostra que o Teste Stroop é promissoriamente confiável como instrumento de avaliação neuropsicológica, podendo potencialmente ser utilizado para qualquer faixa etária da população. Em estudos futuros são necessárias amostras com números mais elevados de participantes nas faixas etárias acima dos 30 anos, representativas dos níveis de escolaridade abaixo do 9ºano, a exercerem profissões manuais, e com residência noutras regiões geográficas para além do Centro. / Objectives: The present study is part of the Project - Estudos Normativos de Instrumentos Neuropsicologicos (ENIN) and aims to analyze the psychometric properties of the Stroop test. Methods: We have selected, and we also enquired 671 subjects. The independent variables studied were age, gender, education and profession. Several tests were used in this study for analysis of convergent validity: convergent validity: Frontal Assessment Battery-FAB, Complex Figure Rey-Osterrieth and the clock test. We also studied the internal consistency and the temporal stability of the Stroop test. Results: Our sample was composed of 310 subjects (46.2%) male and 361 (53.8%) females, with ages between 18 and 100 years (M = 41.12; SD = 20.85). The level of schooling (M = 5.71; SD = 1.45) ranged between the 1st cycle and the Higher Education. The professions were mainly intellectual ones (N = 281; 84.9%). On sociodemographic variables, we found that the age, sex, education and profession influenced reading and Color naming of Stroop test. Regarding convergent validity, Color naming showed weak positive correlations with the FAB, Complex Figure Rey-Copy, and the clock test. Color naming moderate positive correlations with the reading. The internal consistency of the Stroop test was high (α = 0.99). The test-retest correlation was significant only for Color naming. Conclusion: This study shows that the Stroop test is promissory reliable instrument of neuropsychological assessment and may potentially be used for any age range of the population. In future research, it is necessary to enroll samples with higher numbers of participants above 30 years, representative of the levels of schooling below the 9º grade, with more manual professions represented, and with residence in other geographic regions in addition to the Center region of Portugal.

Propriedades psicométricas da versão Torga do Teste Stroop

RESUMO Objetivos: Uma nova versão portuguesa do teste Stroop é fundamental para a avaliação neuropsicológica. A versão portuguesa prévia incluía cores que muitas pessoas não conseguiam distinguir. Assim, é objetivo descrever as propriedades psicométricas de uma nova versão, designada versão Torga do Teste Stroop, numa amostra da população portuguesa. Métodos: Inserida no projeto Estudos Normativos de Instrumentos Neuropsicológicos, esta investigação conta com uma amostra global constituída por 544 participantes (241 homens e 303 mulheres) com idades compreendidas entre os 18 e os 97 anos. A avaliação foi realizada com recurso à versão Torga do Teste Stroop, à Figura Complexa de Rey-Osterrieth e à Bateria de Avaliação Frontal enquanto instrumentos de avaliação das funções executivas. Resultados: A versão Torga do Teste Stroop revelou uma consistência interna muito boa (α de Cronbach = 0,99). Revelou também adequada estabilidade temporal e validade convergente. Conclusão: A versão Torga do Teste Stroop aparenta ser um instrumento apropriado à avaliação neuropsicológica de adultos portugueses. Considerando a importância deste teste no contexto da avaliação neuropsicológica, incentivam-se estudos com novas amostras, incluindo amostras clínicas. ABSTRACT Goals: A new Portuguese version of the Stroop Test is essential for the neuropsychological assessment. The previous Portuguese version included colors that many people could not distinguish. Thus, it is aimed to describe the psychometric properties of a new version, called the Torga version of the Stroop Test in a sample of the Portuguese population. Methods: Being part of the Estudos Normativos de Instrumentos Neuropsicológicos/ Normative Studies of Neuropsychological Instruments, this research has a global sample of 544 subjects (241 men and 303 women) aged from 18 to 97 years. The assessment included the Torga version of the Stroop Test, the Rey-Osterrieth Complex Figure and the Frontal Battey Assessment, used as measures of executive functions. Results: The Torga version of the Stroop Test showed a very good internal consistency (Cronbach's α = 0.99). It also revealed an adequate temporal stability and convergent validity. Conclusion: The Torga version of the Stroop Test appears to be an adequate instrument for the neuropsychological assessment of Portuguese adults. Considering the importance of this test in the context of neuropsychological assessment, more studies with new samples, including clinical samples are encouraged.

Multi-Disciplinary Applications of Oceanographic Geophysical Data Collection

Thesis (Ph.D.)--University of Washington, 2016-08

Anomaly Detection in Noisy Images

Finding rare events in multidimensional data is an important detection problem that has applications in many fields, such as risk estimation in insurance industry, finance, flood prediction, medical diagnosis, quality assurance, security, or safety in transportation. The occurrence of such anomalies is so infrequent that there is usually not enough training data to learn an accurate statistical model of the anomaly class. In some cases, such events may have never been observed, so the only information that is available is a set of normal samples and an assumed pairwise similarity function. Such metric may only be known up to a certain number of unspecified parameters, which would either need to be learned from training data, or fixed by a domain expert. Sometimes, the anomalous condition may be formulated algebraically, such as a measure exceeding a predefined threshold, but nuisance variables may complicate the estimation of such a measure. Change detection methods used in time series analysis are not easily extendable to the multidimensional case, where discontinuities are not localized to a single point. On the other hand, in higher dimensions, data exhibits more complex interdependencies, and there is redundancy that could be exploited to adaptively model the normal data. In the first part of this dissertation, we review the theoretical framework for anomaly detection in images and previous anomaly detection work done in the context of crack detection and detection of anomalous components in railway tracks. In the second part, we propose new anomaly detection algorithms. The fact that curvilinear discontinuities in images are sparse with respect to the frame of shearlets, allows us to pose this anomaly detection problem as basis pursuit optimization. Therefore, we pose the problem of detecting curvilinear anomalies in noisy textured images as a blind source separation problem under sparsity constraints, and propose an iterative shrinkage algorithm to solve it. Taking advantage of the parallel nature of this algorithm, we describe how this method can be accelerated using graphical processing units (GPU). Then, we propose a new method for finding defective components on railway tracks using cameras mounted on a train. We describe how to extract features and use a combination of classifiers to solve this problem. Then, we scale anomaly detection to bigger datasets with complex interdependencies. We show that the anomaly detection problem naturally fits in the multitask learning framework. The first task consists of learning a compact representation of the good samples, while the second task consists of learning the anomaly detector. Using deep convolutional neural networks, we show that it is possible to train a deep model with a limited number of anomalous examples. In sequential detection problems, the presence of time-variant nuisance parameters affect the detection performance. In the last part of this dissertation, we present a method for adaptively estimating the threshold of sequential detectors using Extreme Value Theory on a Bayesian framework. Finally, conclusions on the results obtained are provided, followed by a discussion of possible future work.

Performance analysis in soccer: applications of player tracking technology

The aim of this thesis was threefold, firstly, to compare current player tracking technology in a single game of soccer. Secondly, to investigate the running requirements of elite women’s soccer, in particular the use and application of athlete tracking devices. Finally, how can game style be quantified and defined. Study One compared four different match analysis systems commonly used in both research and applied settings: video-based time-motion analysis, a semi-automated multiple camera based system, and two commercially available Global Positioning System (GPS) based player tracking systems at 1 Hertz (Hz) and 5 Hz respectively. A comparison was made between each of the systems when recording the same game. Total distance covered during the match for the four systems ranged from 10 830 ± 770 m (semi-automated multiple camera based system) to 9 510 ± 740m (video-based time-motion analysis). At running speeds categorised as high-intensity running (>15 km⋅h-1), the semi-automated multiple camera based system reported the highest distance of 2 650 ± 530 m with video-based time-motion analysis reporting the least amount of distance covered with 1 610 ± 370 m. At speeds considered to be sprinting (>20 km⋅h-1), the video-based time-motion analysis reported the highest value (420 ± 170 m) and 1 Hz GPS units the lowest value (230 ± 160 m). These results demonstrate there are differences in the determination of the absolute distances, and that comparison of results between match analysis systems should be made with caution. Currently, there is no criterion measure for these match analysis methods and as such it was not possible to determine if one system was more accurate than another. Study Two provided an opportunity to apply player-tracking technology (GPS) to measure activity profiles and determine the physical demands of Australian international level women soccer players. In four international women’s soccer games, data was collected on a total of 15 Australian women soccer players using a 5 Hz GPS based athlete tracking device. Results indicated that Australian women soccer players covered 9 140 ± 1 030 m during 90 min of play. The total distance covered by Australian women was less than the 10 300 m reportedly covered by female soccer players in the Danish First Division. However, there was no apparent difference in the estimated "#$%&', as measured by multi-stage shuttle tests, between these studies. This study suggests that contextual information, including the “game style” of both the team and opposition may influence physical performance in games. Study Three examined the effect the level of the opposition had on the physical output of Australian women soccer players. In total, 58 game files from 5 Hz athlete-tracking devices from 13 international matches were collected. These files were analysed to examine relationships between physical demands, represented by total distance covered, high intensity running (HIR) and distances covered sprinting, and the level of the opposition, as represented by the Fédération Internationale de Football Association (FIFA) ranking at the time of the match. Higher-ranking opponents elicited less high-speed running and greater low-speed activity compared to playing teams of similar or lower ranking. The results are important to coaches and practitioners in the preparation of players for international competition, and showed that the differing physical demands required were dependent on the level of the opponents. The results also highlighted the need for continued research in the area of integrating contextual information in team sports and demonstrated that soccer can be described as having dynamic and interactive systems. The influence of playing strategy, tactics and subsequently the overall game style was highlighted as playing a significant part in the physical demands of the players. Study Four explored the concept of game style in field sports such as soccer. The aim of this study was to provide an applied framework with suggested metrics for use by coaches, media, practitioners and sports scientists. Based on the findings of Studies 1- 3 and a systematic review of the relevant literature, a theoretical framework was developed to better understand how a team’s game style could be quantified. Soccer games can be broken into key moments of play, and for each of these moments we categorised metrics that provide insight to success or otherwise, to help quantify and measure different methods of playing styles. This study highlights that to date, there had been no clear definition of game style in team sports and as such a novel definition of game style is proposed that can be used by coaches, sport scientists, performance analysts, media and general public. Studies 1-3 outline four common methods of measuring the physical demands in soccer: video based time motion analysis, GPS at 1 Hz and at 5 Hz and semiautomated multiple camera based systems. As there are no semi-automated multiple camera based systems available in Australia, primarily due to cost and logistical reasons, GPS is widely accepted for use in team sports in tracking player movements in training and competition environments. This research identified that, although there are some limitations, GPS player-tracking technology may be a valuable tool in assessing running demands in soccer players and subsequently contribute to our understanding of game style. The results of the research undertaken also reinforce the differences between methods used to analyse player movement patterns in field sports such as soccer and demonstrate that the results from different systems such as GPS based athlete tracking devices and semi-automated multiple camera based systems cannot be used interchangeably. Indeed, the magnitude of measurement differences between methods suggests that significant measurement error is evident. This was apparent even when the same technologies are used which measure at different sampling rates, such as GPS systems using either 1 Hz or 5 Hz frequencies of measurement. It was also recognised that other factors influence how team sport athletes behave within an interactive system. These factors included the strength of the opposition and their style of play. In turn, these can impact the physical demands of players that change from game to game, and even within games depending on these contextual features. Finally, the concept of what is game style and how it might be measured was examined. Game style was defined as "the characteristic playing pattern demonstrated by a team during games. It will be regularly repeated in specific situational contexts such that measurement of variables reflecting game style will be relatively stable. Variables of importance are player and ball movements, interaction of players, and will generally involve elements of speed, time and space (location)".

O equilíbrio entre o trabalho e a vida privada: A adequação das práticas organizacionais às necessidades dos trabalhadores

Dissertação de Mestrado apresentada ao ISPA - Instituto Universitário

Correlação entre o sinal mecanomiográfico e a escala modificada de Ashworth durante avaliação clínica da espasticidade

Spasticity is a common disorder in people who have upper motor neuron injury. The involvement may occur at different levels. The Modified Ashworth Scale (MAS) is the most used method to measure involvement levels. But it corresponds to a subjective evaluation. Mechanomyography (MMG) is an objective technique that quantifies the muscle vibration during the contraction and stretching events. So, it may assess the level of spasticity accurately. This study aimed to investigate the correlation between spasticity levels determined by MAS with MMG signal in spastic and not spastic muscles. In the experimental protocol, we evaluated 34 members of 22 volunteers, of both genders, with a mean age of 39.91 ± 13.77 years. We evaluated the levels of spasticity by MAS in flexor and extensor muscle groups of the knee and/or elbow, where one muscle group was the agonist and one antagonist. Simultaneously the assessment by the MAS, caught up the MMG signals. We used a custom MMG equipment to register and record the signals, configured in LabView platform. Using the MatLab computer program, it was processed the MMG signals in the time domain (median energy) and spectral domain (median frequency) for the three motion axes: X (transversal), Y (longitudinal) and Z (perpendicular). For bandwidth delimitation, we used a 3rd order Butterworth filter, acting in the range of 5-50 Hz. Statistical tests as Spearman's correlation coefficient, Kruskal-Wallis test and linear correlation test were applied. As results in the time domain, the Kruskal-Wallis test showed differences in median energy (MMGME) between MAS groups. The linear correlation test showed high linear correlation between MAS and MMGME for the agonist muscle as well as for the antagonist group. The largest linear correlation occurred between the MAS and MMG ME for the Z axis of the agonist muscle group (R2 = 0.9557) and the lowest correlation occurred in the X axis, for the antagonist muscle group (R2 = 0.8862). The Spearman correlation test also confirmed high correlation for all axes in the time domain analysis. In the spectral domain, the analysis showed an increase in the median frequency (MMGMF) in MAS’ greater levels. The highest correlation coefficient between MAS and MMGMF signal occurred in the Z axis for the agonist muscle group (R2 = 0.4883), and the lowest value occurred on the Y axis for the antagonist group (R2 = 0.1657). By means of the Spearman correlation test, the highest correlation occurred between the Y axis of the agonist group (0.6951; p <0.001) and the lowest value on the X axis of the antagonist group (0.3592; p <0.001). We conclude that there was a significantly high correlation between the MMGME and MAS in both muscle groups. Also between MMG and MAS occurred a significant correlation, however moderate for the agonist group, and low for the antagonist group. So, the MMGME proved to be more an appropriate descriptor to correlate with the degree of spasticity defined by the MAS.

Quantificação de açúcares com uma língua eletrónica: calibração multivariada com seleção de sensores

Este trabalho incide na análise dos açúcares majoritários nos alimentos (glucose, frutose e sacarose) com uma língua eletrónica potenciométrica através de calibração multivariada com seleção de sensores. A análise destes compostos permite contribuir para a avaliação do impacto dos açúcares na saúde e seu efeito fisiológico, além de permitir relacionar atributos sensoriais e atuar no controlo de qualidade e autenticidade dos alimentos. Embora existam diversas metodologias analíticas usadas rotineiramente na identificação e quantificação dos açúcares nos alimentos, em geral, estes métodos apresentam diversas desvantagens, tais como lentidão das análises, consumo elevado de reagentes químicos e necessidade de pré-tratamentos destrutivos das amostras. Por isso se decidiu aplicar uma língua eletrónica potenciométrica, construída com sensores poliméricos selecionados considerando as sensibilidades aos açucares obtidas em trabalhos anteriores, na análise dos açúcares nos alimentos, visando estabelecer uma metodologia analítica e procedimentos matemáticos para quantificação destes compostos. Para este propósito foram realizadas análises em soluções padrão de misturas ternárias dos açúcares em diferentes níveis de concentração e em soluções de dissoluções de amostras de mel, que foram previamente analisadas em HPLC para se determinar as concentrações de referência dos açúcares. Foi então feita uma análise exploratória dos dados visando-se remover sensores ou observações discordantes através da realização de uma análise de componentes principais. Em seguida, foram construídos modelos de regressão linear múltipla com seleção de variáveis usando o algoritmo stepwise e foi verificado que embora fosse possível estabelecer uma boa relação entre as respostas dos sensores e as concentrações dos açúcares, os modelos não apresentavam desempenho de previsão satisfatório em dados de grupo de teste. Dessa forma, visando contornar este problema, novas abordagens foram testadas através da construção e otimização dos parâmetros de um algoritmo genético para seleção de variáveis que pudesse ser aplicado às diversas ferramentas de regressão, entre elas a regressão pelo método dos mínimos quadrados parciais. Foram obtidos bons resultados de previsão para os modelos obtidos com o método dos mínimos quadrados parciais aliado ao algoritmo genético, tanto para as soluções padrão quanto para as soluções de mel, com R²ajustado acima de 0,99 e RMSE inferior a 0,5 obtidos da relação linear entre os valores previstos e experimentais usando dados dos grupos de teste. O sistema de multi-sensores construído se mostrou uma ferramenta adequada para a análise dos iii açúcares, quando presentes em concentrações maioritárias, e alternativa a métodos instrumentais de referência, como o HPLC, por reduzir o tempo da análise e o valor monetário da análise, bem como, ter um preparo mínimo das amostras e eliminar produtos finais poluentes.

Satisfação dos utentes com o tratamento da dor

A dor constitui atualmente um enorme obstáculo no quotidiano de mihares de pessoas em todo o mundo. Por essa razão, é considerada um problema de saúde pública, não só pelas repercussões individuais que provoca, mas também pelas consequências graves aos níveis social e económico. Desta forma, este estudo pretende examinar a satisfação dos utentes com o tratamento da dor, determinando os fatores sociodemográficos, clínicos e psicossociais (personalidade e espiritualidade) que influenciam essa mesma satisfação. Trata-se de um estudo transversal, descritivo-correlacional e quantitativo. A amostra utilizada é constituída por 78 participantes, com idades compreendidas entre os 30 anos e os 82 anos, correspondendo a uma média de idades de 64,88 anos. A maioria é casada/vive em união de fato e possui graus de escolaridade baixos (1º ciclo). Para se proceder á recolha de dados foi aplicado um questionário, cuja finalidade era a caraterização clinica e sociodemográfica dos participantes. Foram também usadas as seguintes escalas: Escala de satisfação para o tratamento da dor (PTSS), Escala de espiritualidade e o Inventário da personalidade (NEO-FFI-20). Os resultados demonstram que a maioria da amostra apresenta dor crónica, de origem músculo-esquelética e o tratamento farmacológico constitui o tratamento de eleição. A maioria (91%) dos participantes refere estar satisfeita ou muito satisfeita com o atual tratamento para a sua dor. Contudo, a análise dos dados revelou a existência de diferenças estatisticamente significativas entre a variável satisfação em diferentes dimensões com as seguintes variáveis sociodemográficas: género (p= 0.003, idade (p=0.010) e estado civil (p=0.045); clínicas: período temporal da dor (p= 0.013 e p=0.014), tipo de tratamento (p=0.011), programa de reabilitação (p= 0.003 e p= 0.005), seguimento em consulta da dor (p≤ 0.05 em cinco sub-dimensões da escala de satisfação), psicossociais: a personalidade em todas as dimensões com exceção da dimensão neuroticismo, e por fim a espiritualidade global (p= 0.008) e também na sua dimensão crenças (p=0.010). Palavras- chave: dor, satisfação com o tratamento, personalidade, espiritualidade.

A kinetic energy budget and internal instabilities in the Fine Resolution Antarctic Model

An energy analysis of the Fine Resolution Antarctic Model (FRAM) reveals the instability processes in the model. The main source of time-mean kinetic energy is the wind stress and the main sink is transfer to mean potential energy. The wind forcing thus helps maintain the density structure. Transient motions result from internal instabilities of the Bow rather than seasonal variations of the forcing. Baroclinic instability is found to be an important mechanism in FRAM. The highest values of available potential energy are found in the western boundary regions as well as in the Antarctic Circumpolar Current (ACC) region. All subregions with predominantly zonal flow are found to be baroclinically unstable. The observed deficit of eddy kinetic energy in FRAM occurs as a result of the high lateral friction, which decreases the growth rates of the most unstable waves. This high friction is required for the numerical stability of the model and can only be made smaller by using a finer horizontal resolution. A grid spacing of at least 10-15 km would be required to resolve the most unstable waves in the southern part of the domain. Barotropic instability is also found to be important for the total domain balance. The inverse transfer (that is, transfer from eddy to mean kinetic energy) does not occur anywhere, except in very localized tight jets in the ACC. The open boundary condition at the northern edge of the model domain does not represent a significant source or sink of eddy variability. However, a large exchange between internal and external mode energies is found to occur. It is still unclear how these boundary conditions affect the dynamics of adjacent regions.

NUMERICAL SIMULATION STUDY OF VIBRATION MITIGATION EFFECTIVENESS OF TUNED MASS DAMPERS FOR TRAFFIC SIGNAL MAST ARM STRUCTURES

Fatigue damage in the connections of single mast arm signal support structures is one of the primary safety concerns because collapse could result from fatigue induced cracking. This type of cantilever signal support structures typically has very light damping and excessively large wind-induced vibration have been observed. Major changes related to fatigue design were made in the 2001 AASHTO LRFD Specification for Structural Supports for Highway Signs, Luminaries, and Traffic Signals and supplemental damping devices have been shown to be promising in reducing the vibration response and thus fatigue load demand on mast arm signal support structures. The primary objective of this study is to investigate the effectiveness and optimal use of one type of damping devices termed tuned mass damper (TMD) in vibration response mitigation. Three prototype single mast arm signal support structures with 50-ft, 60-ft, and 70-ft respectively are selected for this numerical simulation study. In order to validate the finite element models for subsequent simulation study, analytical modeling of static deflection response of mast arm of the signal support structures was performed and found to be close to the numerical simulation results from beam element based finite element model. A 3-DOF dynamic model was then built using analytically derived stiffness matrix for modal analysis and time history analysis. The free vibration response and forced (harmonic) vibration response of the mast arm structures from the finite element model are observed to be in good agreement with the finite element analysis results. Furthermore, experimental test result from recent free vibration test of a full-scale 50-ft mast arm specimen in the lab is used to verify the prototype structure’s fundamental frequency and viscous damping ratio. After validating the finite element models, a series of parametric study were conducted to examine the trend and determine optimal use of tuned mass damper on the prototype single mast arm signal support structures by varying the following parameters: mass, frequency, viscous damping ratio, and location of TMD. The numerical simulation study results reveal that two parameters that influence most the vibration mitigation effectiveness of TMD on the single mast arm signal pole structures are the TMD frequency and its viscous damping ratio.

Long-term relationship between energy consumption and GDP in Latin America: an empirical assessment using panel data

The main objetive of this research is to evaluate the long term relationship between energy consumption and GDP for some Latin American countries in the period 1980-2009 -- The estimation has been done through the non-stationary panel approach, using the production function in order to control other sources of GDP variation, such as capital and labor -- In addition to this, a panel unit root tests are used in order to identify the non-stationarity of these variables, followed by the application of panel cointegration test proposed by Pedroni (2004) to avoid a spurious regression (Entorf, 1997; Kao, 1999)

The meaning of implied volatility in pricing stock options traded in options markets

Ph.D. in the Faculty of Business Administration