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Técnicas audiovisuais como recurso didáctico : aplicação do software educativo “Saber mais matemática 11º ano"

Pereira, Ricardo Fernando Ferreira Carneiro
Fonte: Universidade Aberta de Portugal Publicador: Universidade Aberta de Portugal
Tipo: Dissertação de Mestrado
Publicado em //2007 POR
Relevância na Pesquisa
17.2%
Dissertação de Mestrado em Ensino das Ciências apresentada à Universidade Aberta; Resumo - É inegável que as Novas Tecnologias da Informação desempenham um papel cada vez mais relevante na vida quotidiana. Para aproveitar estas potencialidades, mais precisamente dos computadores e dos Softwares Educativos, decidimos abandonar, por algum tempo, as práticas lectivas tradicionais e enveredar pelos caminhos das Novas Tecnologias de modo que as práticas lectivas fossem capazes de suscitar interesse e melhorar a aprendizagem dos alunos. A utilização do Software Educativo pode estimular a autonomia nos alunos, no seu estudo em casa e na Escola. Utilizou-se o Software Educativo “Saber Mais Matemática 11º ano" da Porto Editora, em duas escolas, uma Secundária e outra Profissional ao longo de 6 sessões de 60 minutos, na área da Matemática, no 11º ano e 2º ano, respectivamente, no currículo de “sucessões". O estudo implementado visou investigar a possibilidade da utilização do Software Educativo como forma de melhorar as aprendizagens dos alunos, estimulando o seu interesse, empenho e atenção. Procurou-se também averiguar a existência de diferenças significativas entre escolas no que respeita ao efeito do programa escolhido. Assim...

Caractérisation des occupations du sol en milieu urbain par imagerie radar

Codjia, Claude
Fonte: Université de Montréal Publicador: Université de Montréal
Tipo: Thèse ou Mémoire numérique / Electronic Thesis or Dissertation
FR
Relevância na Pesquisa
16.43%
Cette étude vise à tester la pertinence des images RSO - de moyenne et de haute résolution - à la caractérisation des types d’occupation du sol en milieu urbain. Elle s’est basée sur des approches texturales à partir des statistiques de deuxième ordre. Plus spécifiquement, on recherche les paramètres de texture les plus pertinents pour discriminer les objets urbains. Il a été utilisé à cet égard des images Radarsat-1 en mode fin en polarisation HH et Radarsat-2 en mode fin en double et quadruple polarisation et en mode ultrafin en polarisation HH. Les occupations du sol recherchées étaient le bâti dense, le bâti de densité moyenne, le bâti de densité faible, le bâti industriel et institutionnel, la végétation de faible densité, la végétation dense et l’eau. Les neuf paramètres de textures analysés ont été regroupés, en familles selon leur définition mathématique. Les paramètres de ressemblance/dissemblance regroupent l’Homogénéité, le Contraste, la Similarité et la Dissimilarité. Les paramètres de désordre sont l’Entropie et le Deuxième Moment Angulaire. L’Écart-Type et la Corrélation sont des paramètres de dispersion et la Moyenne est une famille à part. Il ressort des expériences que certaines combinaisons de paramètres de texture provenant de familles différentes utilisés dans les classifications donnent de très bons résultants alors que d’autres associations de paramètres de texture de définition mathématiques proches génèrent de moins bons résultats. Par ailleurs on constate que si l’utilisation de plusieurs paramètres de texture améliore les classifications...

Bayesian quantification of thermodynamic uncertainties in dense gas flows

MERLE, Xavier; CINNELLA, Paola
Fonte: Elsevier Publicador: Elsevier
EN
Relevância na Pesquisa
26.71%
A Bayesian inference methodology is developed for calibrating complex equations of state used in numerical fluid flow solvers. Precisely, the input parameters of three equations of state commonly used for modeling the thermodynamic behavior of so-called dense gas flows, – i.e. flows of gases characterized by high molecular weights and complex molecules, working in thermodynamic conditions close to the liquid-vapor saturation curve–, are calibrated by means of Bayesian inference from reference aerodynamic data for a dense gas flow over a wing section. Flow thermodynamic conditions are such that the gas thermodynamic behavior strongly deviates from that of a perfect gas. In the aim of assessing the proposed methodology, synthetic calibration data –specifically, wall pressure data– are generated by running the numerical solver with a more complex and accurate thermodynamic model. The statistical model used to build the likelihood function includes a model-form inadequacy term, accounting for the gap between the model output associated to the best-fit parameters, and the rue phenomenon. Results show that, for all of the relatively simple models under investigation, calibrations lead to informative posterior probability density distributions of the input parameters and improve the predictive distribution significantly. Nevertheless...

Simulation sickness comparison between a limited field of view virtual reality head mounted display (Oculus) and a medium range field of view static ecological driving simulator (Eco2)

AYKENT, Baris; YANG, Zhao; MERIENNE, Frédéric; KEMENY, Andras
Fonte: Society for Modeling & Simulation International Publicador: Society for Modeling & Simulation International
EN
Relevância na Pesquisa
26.43%
In this article, an experimental procedure is presented in order to evaluate the role of having HMD oculus and (Eco2 driving simulator) in terms of driving simulation sickness. The driving simulation sickness is investigated with respect to SSQ (simulator sickness questionnaire) and vestibular dynamics (head movements) of the driver participants for a specific driving scenario. The scenario of driving task is created by using open source “iiVR (institut image virtual reality)” software which is developed by Institut Image Arts et Métiers ParisTech. The experiments are executed in static mode for the driving simulators.

The role of motion platform on postural instability and head vibration exposure at driving simulators

AYKENT, Baris; MERIENNE, Frédéric; PAILLOT, Damien; KEMENY, Andras
Fonte: Elsevier Publicador: Elsevier
EN
Relevância na Pesquisa
26.71%
This paper explains the effect of a motion platform for driving simulators on postural instability and head vibration exposure. The sensed head level-vehicle (visual cues) level longitudinal and lateral accelerations (ax,sensed = ax_head and ay,sensed = ay_head, ayv = ay_veh and ayv = ay_veh) were saved by using a motion tracking sensor and a simulation software respectively. Then, associated vibration dose values (VDVs) were computed at head level during the driving sessions. Furthermore, the postural instabilities of the participants were measured as longitudinal and lateral subject body centre of pressure (XCP and YCP, respectively) displacements just after each driving session via a balance platform. The results revealed that the optic-head inertial level longitudinal accelerations indicated a negative non-significant correlation (r = −.203, p = .154 > .05) for the static case, whereas the optic-head inertial longitudinal accelerations depicted a so small negative non-significant correlation (r = −.066, p = .643 > .05) that can be negligible for the dynamic condition. The XCP for the dynamic case indicated a significant higher value than the static situation (t(47), p < .0001). The VDVx for the dynamic case yielded a significant higher value than the static situation (U(47)...

Reliability Estimation by ALT when no Analytical Model Holds

LANTIERI, Pascal; GUERIN, Fabrice; HAMBLIA, Ridha
Fonte: John Wiley & Sons, Ltd Publicador: John Wiley & Sons, Ltd
EN
Relevância na Pesquisa
26.43%
This paper presents an accelerated life testing method applicable to devices or systems when no analytical relationship with respect to the stress level can be defined. If a numerical approach remains possible, the numerical model can be fitted to the accelerated test results. Thus, long-term failures can be predicted from short tests. This method is carried out in the case of fatigue, the evolution of the damage leading to the failure having to be modeled by a numerical finite element method.

LSE method using the CHSS model

LANTIERI, Pascal; GUERIN, Fabrice; VOICULESCU, Sorin
Fonte: Elsevier Publicador: Elsevier
EN
Relevância na Pesquisa
26.43%
Testing the reliability at a nominal stress level may lead to extensive test time. Estimations of reliability parameters can be obtained faster thanks to step-stress accelerated life tests (ALT). Usually, a transfer functional defined among a given class of parametric functions is required, but Bagdonavičius and Nikulin showed that ALT tests are still possible without any assumption about this functional. When shape and scale parameters of the lifetime distribution change with the stress level, they suggested an ALT method using a model called CHanging Shape and Scale (CHSS). They estimated the lifetime parameters at the nominal stress with maximum likelihood estimation (MLE). However, this method usually requires an initialization of lifetime parameters, which may be difficult when no similar product has been tested before. This paper aims to face this issue by using an iterating least square estimation (LSE) method. It will enable one to initialize the optimization required to carry out the MLE and it will give estimations that can sometimes be better than those given by MLE.

Diagnostics of an Aircraft Engine Pumping Unit Using a Hybrid Approach based-on Surrogate Modeling

LAMOUREUX, Benjamin; MASSÉ, Jean-Rémi; MECHBAL, Nazih
Fonte: IEEE PHM Publicador: IEEE PHM
EN
Relevância na Pesquisa
26.43%
This document introduces a hybrid approach for fault detection and identification of an aircraft engine pumping unit. It is based on the complementarity between a model-based approach accounting for uncertainties aimed at quantifying the degradation modes signatures and a data-driven approach aimed at recalibrating the healthy syndrome from measures. Because of the computational time costs of uncertainties propagation into the physics based model, a surrogate modeling technic called Kriging associated to Latin hypercube sampling is utilized. The hybrid approach is tested on a pumping unit of an aircraft engine and shows good results for computing the degradation modes signatures and performing their detection and identification.

Selection and Validation of Health Indicators in Prognostics and Health Management System Design

LAMOUREUX, Benjamin; MECHBAL, Nazih; MASSÉ, Jean-Rémi
Fonte: IEEE Publicador: IEEE
EN
Relevância na Pesquisa
26.43%
Health Monitoring is the science of system health status evaluation. In the modern industrial world, it is getting more and more importance because it is a powerful tool to increase systems dependability. It is based on the observation of some variables extracted in operation reflecting the condition of a system. The quality of health monitoring strongly depends on the selection of these variables named health indicators. However, the issue in their selection is often underestimated and their validation is, of what is known, an untreated subject. In this paper, the authors introduce a complete methodology for the selection and validation of health indicators in health monitoring systems design. Although it can be applied either downstream on real measured data or upstream on simulated data, the true interest of the method is in the latter application. Indeed, a model-based validation can be integrated in the design phases of the system development process, thereby reducing potential controller retrofit costs and useless data storage. In order to simulate the distribution of health indicators, a well known surrogate model called Kriging is utilized. Eventually, the method is tested on a benchmark system: the high pressure pump of aircraft engines fuel systems. Thanks to the method...

Motion sickness evaluation and comparison for a static driving simulator and a dynamic driving simulator

AYKENT, Baris; MERIENNE, Frédéric; GUILLET, Christophe; PAILLOT, Damien; KEMENY, Andras
Fonte: SAGE Publicador: SAGE
EN
Relevância na Pesquisa
26.71%
This paper deals with driving simulation and in particular with the important issue of motion sickness. The paper proposes a methodology to evaluate the objective illness rating metrics deduced from the motion sickness dose value and questionnaires for both a static simulator and a dynamic simulator. Accelerations of the vestibular cues (head movements) of the subjects were recorded with and without motion platform activation. In order to compare user experiences in both cases, the head-dynamics-related illness ratings were computed from the obtained accelerations and the motion sickness dose values. For the subjective analysis, the principal component analysis method was used to determine the conflict between the subjective assessment in the static condition and that in the dynamic condition. The principal component analysis method used for the subjective evaluation showed a consistent difference between the answers given in the sickness questionnaire for the static platform case from those for the dynamic platform case. The two-tailed Mann–Whitney U test shows the significance in the differences between the self-reports to the individual questions. According to the two-tailed Mann–Whitney U test, experiencing nausea (p = 0.019 < 0.05) and dizziness (p = 0.018 < 0.05) decreased significantly from the static case to the dynamic case. Also...

Mapping a multi-sensory identity territory at the early design stage

GENTNER, Alexandre; BOUCHARD, Carole; ESQUIVEL, Daniel; FAVART, Carole
Fonte: Japanese Society of Kansei Engineering Publicador: Japanese Society of Kansei Engineering
EN
Relevância na Pesquisa
26.7%
This article presents a kansei design methodology. It is placed at the very beginning of the design process and aims to influence the following steps in order to improve the user's understanding and experiencing of the designed product. The experimentation combines in a subtle way the design thinking approach of learning by doing and the kansei engineering quantitative approach. The research presented is based on the results of a previous study that defined the semantic and emotional scope of future hybrid cars for European using visual stimuli. This kansei design methodology creates and assesses multi-sensory atmospheres is order to provide tangible direction composed of vision, touch, hearing and smell stimuli. From the cognitive and affective responses of the 42 participants we were able to detail 3 directions for future cars interiors that aim to enrich the styling design briefs and to influence the design strategies such as the management of the different grades. The research presented here was supported by the Kansei Design department from Toyota Motor Europe (TME-KD). This collaboration also brought an industrial context to it.; SUPPORTED BY TOYOTA EUROPE