Degradation in visibility is often introduced to images captured in poor weather conditions, such as fog or haze. In this paper, a fusion-based transmission estimation method is introduced to adaptively combine two different transmission models. Specifically, the new fusion weighting scheme and the atmospheric light computed from the Gaussian-based dark channel method improves the estimation of the locations of the light sources. To reduce the flickering effect introduced during the process of frame-based dehazing, a flicker-free module is formulated to alleviate the impacts. The system assessments show this approach is capable of superior defogging and dehazing performance, compared to the state-of-the-art methods, both quantitatively and qualitatively

Attended information is perceived quicker than unattended information. This is known as prior entry. When making judgments on the temporal order of two successive stimuli, performance is influenced based on attention. We were interested in whether this same attentional shift would occur when we adopt a crossed hands posture. Typically when making these tactile temporal order judgments, performance declines when the hands are crossed. This may be due to a greater influence of the external environment in the crossed posture. We investigated this by providing an exogenous visual cue at one or both of the hands prior to making judgments about the temporal order of two successive vibrations. This was completed with the hands crossed and uncrossed. In Experiment 1 responses were to which stimulus occurred first. In Experiment 2 participants responded to which stimulus occurred second. Changing the response requirement did not influence overall performance. In both experiments we observed prior entry that was in the same direction for both crossed and uncrossed postures. The size of the prior entry effect was larger when the hands were crossed. We remap tactile information quickly to external coordinates, however we are less certain of the hand’s location. / Thesis / Master of Science (MSc)

No description available.

<p> This study was designed to examine three issues concerning the learning of a new coordination pattern. The first issue examined was the root of the conflicting findings of previous work concerning the effect of learning a novel coordination pattern on the performance an intrinsically stable antiphase pattern (Fontaine, Lee, & Swinnen, 1997; Lee, Verschueren & Swinnen, 1995; Zanone & Kelso, 1992). Consideration of these experiments revealed that different metronomes were used, and that this metronome difference is critical because it may have influenced the learners' attentional focus during learning. Therefore, the present experiment sought to examine whether a difference of attentional focus was the cause of this conflict. The second issue was whether the superiority of an external focus over internal focus of attention during learning would be evident in the learning of a new coordination pattern. And last, this study set out to examine the issue of prior learning of a bimanual coordination pattern on the learning of a new coordination pattern. Two groups of participants (one with an. internal focus of attention, and the other with an external focus of attention) learned to perform a 90° relative phase (RP) coordination pattern over two practice sessions, and were then asked to perform a 135° RP pattern in a third session. An additional two groups of participants (one with an internal focus of attention, and the other with an external focus of attention), served as controls, and learned to perform the 135° RP pattern over all three sessions. Results of this experiment did not support the hypothesis that a difference in attentional focus during learning is responsible for the conflicting findings concerning the effect of learning on intrinsic pattern performance. Although the results seem to indicate that an external focus of attention is more beneficial than an internal focus of attention during learning of a new coordination pattern, further work without feedback as a confounding factor is required. Finally, results show that prior learning does influence the learning of a new coordination pattern in that positive transfer of learning was evident (prior learning of the 90° pattern facilitated performance of the 135° pattern), and findings provide evidence for the creation of a new attractor with learning. </p> / Thesis / Master of Science (MSc)

A review of the research indicates that identifying self as a teacher can be a life-long, complex personal and social process. This researcher investigated 4 pre-collegiate students' construction of a teaching identity during their participation in an introduction to teaching course conducted in a rural high school located in a southeastern state. Two purposes framed this investigation, 1) to gain an in-depth understanding of the pre-collegiate students' past and present experiences related to teaching and the meanings the students make of these experiences, and 2) to examine these experiences as connected to construction of personal teaching identities. Using a life history methodology, data sources included 3 interviews, drawings of self as a teacher, journal writings, and personal experience writings. The findings are presented in 4 narratives one for each participant. Each narrative, represented by an exemplar quote, (i.e., Being There, Being a Kid, Right Heart, Being A Helper) illuminates the nature of the participants' teaching prototype, which emerged from past and present educational experiences. Results indicate that the participants possessed well-defined beliefs pertaining to caring teachers and to teaching as a profession, in addition, to commonly held cultural teaching beliefs. These beliefs guided their course experiences and self-assessment of a teaching identity. Although the identification to a teaching identity varied among the 4 participants, results indicate that 1 participant was actively constructing a storied teaching identity. A storied teaching identity involved a significant nuclear episode with a teacher that became the bound context for a teaching story. This type of high school level career studies course can assist in strengthening the recruitment pool of teacher education candidates and assist in testing a vocational teaching identity. Implications are offered for future research involving pre-collegiate students enrolled in an introduction to teaching course and investigation of storied teaching identities. / Ph. D.

A fundamental question on visual system in neuroscience is how the visual stimuli are functionally related to neural responses. This relationship is often explained by the notion of receptive fields, an approximated linear or quasi-linear filter that encodes the high dimensional visual stimuli into neural spikes. Traditional methods for estimating the filter do not efficiently exploit prior information about the structure of neural receptive fields. Here, we propose several approaches to design the prior distribution over the filter, considering the neurophysiological fact that receptive fields tend to be localized both in space-time and spatio-temporal frequency domain. To automatically regularize the estimation of neural receptive fields, we use the evidence optimization technique, a MAP (maximum a posteriori) estimation under a prior distribution whose parameters are set by maximizing the marginal likelihood. Simulation results show that the proposed methods can estimate the receptive field using datasets that are tens to hundreds of times smaller than those required by traditional methods. / text

In this thesis, a single image dehazing method based on modified dark channel prior and haze (fog) density detection is proposed. Dark channel prior dehazing algorithm is achieved good results for some haze images. However, we observed that haze images contain low and high haze density. Thus, the region of low haze density is unnecessary to dehaze. To solve this problem, we first defined the HSV distance, pixel-based dark channel prior and pixel-based bright channel prior to estimate the haze density. Further to enhance the dehazing performance of dark channel prior, the atmospheric light value and dehazing weighting is revised based on the HSV distance. Then the new transmission map is obtained. After that, a bilateral filter is applied to refine the transmission map, which can provide the higher accuracy of transmission map. Finally, the haze-free image is recovered by combining the input image and the refined transmission map. As a result, high-quality haze-free image can be recovered with lower computational complexity, which can be naturally extended to video dehazing.

A Lei de Licitações e Contratos, em seu artigo 113, instituiu regra garantidora do controle das despesas e demais instrumentos insertos na mencionada lei ordinária federal aos Tribunais de Contas. O mesmo diploma confere, outrossim, a faculdade aos Tribunais de Contas de solicitar editais de licitação antes da fase de abertura das propostas. Fruto desta lei de licitações em vigor, com vistas a assegurar o amplo direito de petição, foi admitida a possibilidade que todo licitante, ou pessoa física ou jurídica, que observe irregularidade em algum item de edital formulado pela Administração Pública, pudesse representar ao Tribunal de Contas, contra o que entender de ilegal ou irregular, podendo até pleitear a suspensão do procedimento licitatório. Desde que formulada tal petição apresentando indícios de irregularidades no edital, a Corte de Contas pode, com fulcro no artigo 113 da Lei 8.666/93, até o dia anterior à data prevista para a abertura dos envelopes, requisitá-lo, com outros elementos completos, para proceder ao seu exame prévio. Nesta hipótese, o Tribunal, à vista dos elementos processuais poderá determinar a suspensão do procedimento licitatório, até que decida o processo, concluindo por determinar retificação nos itens em que houver irregularidade ou, em não havendo, cancelar a suspensão, podendo o Órgão continuar o normal procedimento. Esta inovação legal implicou na mudança do modelo de fiscalização do Tribunal, que, via de regra, só controla posteriormente. Neste caso, como o próprio nome indica, o exame é prévio. Ocorre que tal inovação gerou críticas formuladas por certas correntes doutrinárias (1) e por administradores públicos, no sentido de afirmarem que tal controle externo não poderia implicar na direta interferência na gestão dos órgãos ou entidades a ele submetidos nem ingerência no exercício de suas competências. O presente trabalho se propôs a analisar esta competência atribuída pelo legislador constituinte ao Tribunal de Contas, no exercício da função de controle prévio no tocante aos certames licitatórios e contratos da Administração, além de seus reflexos na gestão dos órgãos ou entidades submetidos a este controle. / The Procurement and Contracts Law, in Article 113, guaranteeing the rule instituted cost control and inserts other instruments mentioned in the federal common law Courts of Auditors. The same law provides, moreover, the right to audit courts to request the bidding stage before the opening of tenders. Result of this bidding law in force, with a view to ensuring full right of petition, admitted the possibility that any bidder or person or entity who observes any irregularity in item announcement made by the Administration, could represent to the Court of Auditors, to understand against the illegal or irregular, and may even demand the suspension of the bidding process. Since such a request formulated by presenting evidence of irregularities in the notice, the Court of Auditors may, with the fulcrum in Article 113 of Law 8666/93, until the day before the date scheduled for the opening of the envelopes, order it, complete with other elements to proceed to the preliminary examination. In this case, the Court, in view of the procedural elements may decide to suspend the bidding process, until you decide the process for determining correction in concluding that there are items or irregularity in the absence thereof, cancel the suspension, the Board may continue normal procedure. This legal innovation resulted in changing the model of the Court ruled that, as a rule, only judges later. In this case, as its name indicates, the exam in advance. It happens that this innovation has generated criticism by certain doctrinal trends as well as public administrators, to assert that such external control could not involve the direct interference in the management of the agencies or entities to the subject or interference with the exercise of its powers. This study proposes to examine this constitutional power granted by the legislature to the Court, in exercising control with respect to the previous exhibitions of the bidding and contract administration as well as your reflexes in the management of agencies or entities subject to this control.

In the framework of Bayesian model-based clustering based on a finite mixture of Gaussian distributions, we present a joint approach to estimate the number of mixture components and identify cluster-relevant variables simultaneously as well as to obtain an identified model. Our approach consists in specifying sparse hierarchical priors on the mixture weights and component means. In a deliberately overfitting mixture model the sparse prior on the weights empties superfluous components during MCMC. A straightforward estimator for the true number of components is given by the most frequent number of non-empty components visited during MCMC sampling. Specifying a shrinkage prior, namely the normal gamma prior, on the component means leads to improved parameter estimates as well as identification of cluster-relevant variables. After estimating the mixture model using MCMC methods based on data augmentation and Gibbs sampling, an identified model is obtained by relabeling the MCMC output in the point process representation of the draws. This is performed using K-centroids cluster analysis based on the Mahalanobis distance. We evaluate our proposed strategy in a simulation setup with artificial data and by applying it to benchmark data sets. (authors' abstract)

Les métamodèles statistiques sont régulièrement confrontés au manque de données qui engendre des difficultés à estimer les paramètres. Le paradigme bayésien fournit un moyen élégant de contourner le problème en décrivant la connaissance que nous avons des paramètres par une loi de probabilité a posteriori au lieu de la résumer par une estimation ponctuelle. Cependant, ce paradigme nécessite de définir une loi a priori adéquate, ce qui est un exercice difficile en l'absence de jugement d'expert. L'école bayésienne objective propose des priors par défaut dans ce genre de situation telle que le prior de référence de Berger-Bernardo. Un tel prior a été calculé par Berger, De Oliveira and Sansó [2001] pour le modèle de krigeage avec noyau de covariance isotrope. Une extension directe au cas des noyaux anisotropes poserait des problèmes théoriques aussi bien que pratiques car la théorie de Berger-Bernardo ne peut s'appliquer qu'à un jeu de paramètres ordonnés. Or dans ce cas de figure, tout ordre serait nécessairement arbitraire. Nous y substituons une solution bayésienne objective fondée sur les posteriors de référence conditionnels. Cette solution est rendue possible par une théorie du compromis entre lois conditionnelles incompatibles. Nous montrons en outre qu'elle est compatible avec le krigeage trans-gaussien. Elle est appliquée à un cas industriel avec des données non-stationnaires afin de calculer des Probabilités de Détection de défauts (POD de l'anglais Probability Of Detection) par tests non-destructifs dans les tubes de générateur de vapeur de centrales nucléaires. / A recurring problem in surrogate modelling is the scarcity of available data which hinders efforts to estimate model parameters. The Bayesian paradigm offers an elegant way to circumvent the problem by describing knowledge of the parameters by a posterior probability distribution instead of a pointwise estimate. However, it involves defining a prior distribution on the parameter. In the absence of expert opinion, finding an adequate prior can be a trying exercise. The Objective Bayesian school proposes default priors for such can be a trying exercise. The Objective Bayesian school proposes default priors for such situations, like the Berger-Bernardo reference prior. Such a prior was derived by Berger, De Oliveira and Sansó [2001] for the Kriging surrogate model with isotropic covariance kernel. Directly extending it to anisotropic kernels poses theoretical as well as practical problems because the reference prior framework requires ordering the parameters. Any ordering would in this case be arbitrary. Instead, we propose an Objective Bayesian solution for Kriging models with anisotropic covariance kernels based on conditional reference posterior distributions. This solution is made possible by a theory of compromise between incompatible conditional distributions. The work is then shown to be compatible with Trans-Gaussian Kriging. It is applied to an industrial case with nonstationary data in order to derive Probability Of defect Detection (POD) by non-destructive tests in steam generator tubes of nuclear power plants.