A caricatura, uma imagem da face baseada no exagero de suas características peculiares, geralmente é reconhecida tão bem quanto a fotografia da face sem distorções. Para confecção das caricaturas, exageram-se as diferenças entre a imagem original e um protótipo (face média de um grupo de pessoas); e para confecção das anti-caricaturas essas diferenças são atenuadas. O objetivo desta pesquisa foi investigar se existe um grau de exagero ótimo para que a caricatura represente a face melhor que a fotografia original. Além disso, investigou- se o papel da percepção holística versus percepção componencial no processo de reconhecimento de faces. Foram geradas seis faces prototípicas, masculinas e femininas, de pessoas da população da região de Ribeirão Preto que se auto-declaram branca, parda e preta. A partir das faces prototípicas, foram gerados dois tipos de caricaturas e anticaricaturas: 1. holística: em que todas as diferenças entre a face original e a prototípica foram manipuladas, 2. parcial: em que somente as diferenças de alguns elementos faciais isolados ou combinados entre a face original e a prototípica foram manipuladas. No Experimento I os estímulos teste foram as caricaturas e anti-caricaturas holísticas. No Experimento II os estímulos foram as caricaturas e anti-caricaturas parciais. Em ambos experimentos as caricaturas e anti-caricaturas foram submetidas a julgamentos de similaridade com a face original previamente memorizada. Os resultados do Experimento I indicaram que a melhor representação da face é a fotografia sem distorção e que, nos casos em que a face é atípica em relação ao protótipo, as caricaturas tendem a ser representações tão fidedignas quanto as fotografias sem distorção. Os resultados do Experimento II apontam para a importância dos elementos peculiares no reconhecimento de faces. Comparando-se os resultados dos Experimentos I e II pode-se afirmar que o processamento de faces se dá predominantemente de forma holística e que a manipulação de elementos peculiares da face reduz mais a similaridade entre a face original e a caricatura (ou anti-caricatura) que a manipulação de elementos não-peculiares. / A caricature is an exaggeration of distinctive facial features and is generally recognized just as well as an undistorted photograph of a face. Caricatures can be generated by exaggerating the differences between a face and a prototypical face (average face) and an anticaricature can be generated by reducing those differences. The aim of this study was to investigate whether there is a degree of caricaturing that best captures facial likeness. Moreover, we investigated the role of holistic perception versus componential perception in the facial recognition process. Six prototypical faces, three male and three female, were generated by morphing photographs of Brazilian people from the region of Ribeirão Preto-SP of different races: black, white and mixed race. Two types of caricatures and anticaricatures were generated: 1, holistic: by manipulating of all the differences between a face and the prototypical faces; 2, partial: by manipulating the differences of isolated or combined features between a face and the prototypical face. The stimuli used in Experiment 1 were the holistic caricatures and anticaricatures. In Experiment 2 the stimuli were the partial caricatures and anticaricatures. In both experiments, subjects were asked to rate the similarity between the caricatures and the anticaricatures and a face previously memorized. The results of Experiment 1 provide evidence that the best representation of the face is a photograph without distortion and that, when the face is atypical, the caricatures seem to be as good as photographs without distortion. The results of Experiment 2 point to the importance of the role of distinctive features in face recognition. Comparing the results of Experiments 1 and 2, we can say that the facial recognition process is predominantly holistic but that the manipulation of distinctive facial elements reduces the similarity judgment more than the manipulation of non-distinctive features.

Submitted by Pedro Barros (pedro.silvabarros@ufpe.br) on 2018-09-21T19:23:53Z No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) DISSERTAÇÃO João Henrique Cavalcanti de França.pdf: 4211782 bytes, checksum: 321740befc08c8e0230acf2b5baf609d (MD5) / Approved for entry into archive by Alice Araujo (alice.caraujo@ufpe.br) on 2018-09-24T23:15:43Z (GMT) No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) DISSERTAÇÃO João Henrique Cavalcanti de França.pdf: 4211782 bytes, checksum: 321740befc08c8e0230acf2b5baf609d (MD5) / Made available in DSpace on 2018-09-24T23:15:43Z (GMT). No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) DISSERTAÇÃO João Henrique Cavalcanti de França.pdf: 4211782 bytes, checksum: 321740befc08c8e0230acf2b5baf609d (MD5) Previous issue date: 2017-08-30 / O selo mecânico é o principal elemento de vedação de uma máquina ou equipamento, pois evita que vazamentos indesejados ocorram e possam causar acidentes e prejuízos. As faces de vedação estáticas e dinâmicas são responsáveis por esta função, impedindo que o fluido confinado escape para o meio externo, principalmente quando o equipamento está em operação. Para isso, é imprescindível que as faces possuam valores de planeza e rugosidade superficial satisfatórios. Estes parâmetros são obtidos por meio de lapidação mecanizada ou manual. Na prática, a rugosidade não é avaliada pelas empresas que recuperam selos mecânicos e os valores de planeza são obtidos pela visualização de franjas de interferência, que é um método simples e barato, mas que depende da acuidade visual e experiência do técnico que está realizando a lapidação. Este trabalho propõe comparar os valores de planeza obtidos pela técnica de franjas de interferência e pela medição em uma máquina de medição por coordenadas (MMC), antes e após a lapidação das faces de vedação de selos mecânicos aplicados em bombas de transferência de gás liquefeito de petróleo (GLP), assim como avaliar a qualidade da planeza e da rugosidade superficial obtidas por lapidação manual na oficina de manutenção da Transpetro no Porto de Suape, e por lapidação mecanizada em empresa externa. A rugosidade superficial também foi avaliada através de microscopia óptica e microscopia eletrônica de varredura. Os resultados comprovaram a eficácia do método de lapidação manual e a exatidão da medição de planeza por meio da MMC. Para finalizar o trabalho, foram estimados os principais custos gerados com a falha do selo mecânico e sua manutenção, além dos possíveis prejuízos decorrentes da indisponibilidade simultânea das bombas de GLP, reforçando a importância da recuperação de selos em uma oficina própria. / The mechanical seal is the main sealing element of a machine or equipment because it prevents unwanted leaks from occurring and can cause accidents and damage. Static and dynamic sealing faces are responsible for this function, preventing the confined fluid from escaping into the external environment, especially when the equipment is in operation. For this, it is imperative that the faces have satisfactory flatness and surface roughness values. These parameters are obtained by mechanized or manual lapping. In practice, roughness is not evaluated by companies recovering mechanical seals and flatness values are obtained by viewing fringes of interference, which is a simple and inexpensive method, but which depends on the visual acuity and experience of the technician who is performing the lapping. This work proposes to compare the flatness values obtained by the technique of interference fringes and the measurement in a coordinate measuring machine (CMM), before and after the lapping of the sealing faces of mechanical seals applied in liquefied petroleum gas (LPG) transfer pumps, as well to evaluate the quality of the flatness and of the superficial roughness obtained by manual lapping in the Transpetro maintenance workshop at Suape seaport, and by mechanized lapping in an external company. The surface roughness was also evaluated through optical microscopy and scanning electron microscopy. The results demonstrated the efficacy of the manual lapping method and the accuracy of flatness measurement through CMM. To finalize the work, the main costs generated by the failure of the mechanical seal and its maintenance were estimated, as well as the possible losses due to the simultaneous unavailability of LPG pumps, reinforcing the importance of the recovery of seals inits ownworkshop.

abstract: Transcranial focused ultrasound (tFUS) is a unique neurostimulation modality with potential to develop into a highly sophisticated and effective tool. Unlike any other noninvasive neurostimulation technique, tFUS has a high spatial resolution (on the order of millimeters) and can penetrate across the skull, deep into the brain. Sub-thermal tFUS has been shown to induce changes in EEG and fMRI, as well as perception and mood. This study investigates the possibility of using tFUS to modulate brain networks involved in attention and cognitive control.Three different brain areas linked to saliency, cognitive control, and emotion within the cingulo-opercular network were stimulated with tFUS while subjects performed behavioral paradigms. The first study targeted the dorsal anterior cingulate cortex (dACC), which is associated with performance on cognitive attention tasks, conflict, error, and, emotion. Subjects performed a variant of the Erikson Flanker task in which emotional faces (fear, neutral or scrambled) were displayed in the background as distractors. tFUS significantly reduced the reaction time (RT) delay induced by faces; there were significant differences between tFUS and Sham groups in event related potentials (ERP), event related spectral perturbation (ERSP), conflict and error processing, and heart rate variability (HRV). The second study used the same behavioral paradigm, but targeted tFUS to the right anterior insula/frontal operculum (aIns/fO). The aIns/fO is implicated in saliency, cognitive control, interoceptive awareness, autonomic function, and emotion. tFUS was found to significantly alter ERP, ERSP, conflict and error processing, and HRV responses. The third study targeted tFUS to the right inferior frontal gyrus (rIFG), employing the Stop Signal task to study inhibition. tFUS affected ERPs and improved stopping speed. Using network modeling, causal evidence is presented for rIFG influence on subcortical nodes in stopping. This work provides preliminarily evidence that tFUS can be used to modulate broader network function through a single node, affecting neurophysiological processing, physiologic responses, and behavioral performance. Additionally it can be used as a tool to elucidate network function. These studies suggest tFUS has the potential to affect cognitive function as a clinical tool, and perhaps even enhance wellbeing and expand conscious awareness. / Dissertation/Thesis / Doctoral Dissertation Bioengineering 2020

yes / This study aimed to develop a clinical test of face perception which is applicable to a wide range of patients and can capture normal variability. The Caledonian face test utilises synthetic faces which combine simplicity with sufficient realism to permit individual identification. Face discrimination thresholds (i.e. minimum difference between faces required for accurate discrimination) were determined in an "odd-one-out" task. The difference between faces was controlled by an adaptive QUEST procedure. A broad range of face discrimination sensitivity was determined from a group (N=52) of young adults (mean 5.75%; SD 1.18; range 3.33-8.84%). The test is fast (3-4min), repeatable (test-re-test r2=0.795) and demonstrates a significant inversion effect. The potential to identify impairments of face discrimination was evaluated by testing LM who reported a lifelong difficulty with face perception. While LM's impairment for two established face tests was close to the criterion for significance (Z-scores of -2.20 and -2.27) for the Caledonian face test, her Z-score was -7.26, implying a more than threefold higher sensitivity. The new face test provides a quantifiable and repeatable assessment of face discrimination ability. The enhanced sensitivity suggests that the Caledonian face test may be capable of detecting more subtle impairments of face perception than available tests. / None

yes / Faces are highly complex stimuli that contain a host of information. Such complexity poses the following questions: (a) do observers exhibit preferences for specific information? (b) how does sensitivity to individual face parts compare? These questions were addressed by quantifying sensitivity to different face features. Discrimination thresholds were determined for synthetic faces under the following conditions: (i) ‘full face’: all face features visible; (ii) ‘isolated feature’: single feature presented in isolation; (iii) ‘embedded feature’: all features visible, but only one feature modified. Mean threshold elevations for isolated features, relative to full-faces, were 0.84x, 1.08, 2.12, 3.34, 4.07 and 4.47 for head-shape, hairline, nose, mouth, eyes and eyebrows respectively. Hence, when two full faces can be discriminated at threshold, the difference between the eyes is about four times less than what is required when discriminating between isolated eyes. In all cases, sensitivity was higher when features were presented in isolation than when they were embedded within a face context (threshold elevations of 0.94x, 1.74, 2.67, 2.90, 5.94 and 9.94). This reveals a specific pattern of sensitivity to face information. Observers are between two and four times more sensitive to external than internal features. The pattern for internal features (higher sensitivity for the nose, compared to mouth, eyes and eyebrows) is consistent with lower sensitivity for those parts affected by facial dynamics (e.g. facial expressions). That isolated features are easier to discriminate than embedded features supports a holistic face processing mechanism which impedes extraction of information about individual features from full faces.

No description available.

<p>To assess how the plasticity of the face processing system changes with age, we trained 8-year-olds, 10-year-olds, and adults to differentiate 10 chimpanzee faces at the individual level for 3 days by having them watch a child-friendly training video. Their improvement from baseline was compared to that of age- and gender-matched controls who completed the pre- and post-tests, but did not complete training. Improvement did not vary across age: 8-year-olds, 10-year-olds, and adults all showed similar improvement in accuracy at discriminating the 10 chimpanzee faces on which they were trained. This improvement resulted in the reduction of the own-species bias after training. However, the benefits of training did not generalize to novel exemplars. In addition, participants from both the training and control groups showed a practice effect: their accuracy at discriminating both chimpanzee and human faces improved from pre- to post-test. Taken together, these results demonstrate that the face processing system is somewhat plastic between 8 years of age and adulthood and suggest that this plasticity remains stable throughout this period of development.</p> / Master of Science (MSc)

Made available in DSpace on 2016-03-15T19:40:35Z (GMT). No. of bitstreams: 1 Alessandra Aronovich Vinic.pdf: 2041940 bytes, checksum: 3810ee85be2e8e1fa250540f34eca58f (MD5) Previous issue date: 2008-08-28 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Invasive Development Disorders (IDD) are a group of conditions characterized by the onset of lags and impairments in the development of social, communication and behavioral skills during infancy. The empathy capacity prejudice has been indicated as an endophenotype characteristic of IDD. The present study evaluates and compares empathy in people with IDD and a control group through a task of judging basic facial expressions that are contained in an Empathy Card-deck, an instrument developed by the researcher. Seven male participants with IDD, aged between 6 and 15 years, a minimum IQ of 70 (Wisc III) and all fulfilling criteria for IDD diagnosis (DSM IV) were evaluated. The IDD group erred significantly more than the control group in judging the card-deck of basic facial expression photos (p< 0.001), in the card-deck of drawings (p=0.007) and in both tests when the total performance was analyzed (p< 0.001). There was a significant difference between the control and IDD groups in the expression of doubt (p=0.031) and disgust (p=0.005) in the Drawings Card-deck, and in the expression of disgust (p=0.005) in the Photo Card-deck, always with a greater error index for the IDD group. When analyzing the performance in Photos and Drawings together, there is a statistically significant difference between expressions of doubt (p=0.012), disgust (p<0.001) and surprise (p=0.006). The results obtained reinforce the findings of previous studies about empathic capacity prejudice in individuals with IDD. / Os Transtornos Invasivos do Desenvolvimento (TID) são um grupo de condições caracterizadas pelo início na primeira infância de atrasos e déficits no desenvolvimento das habilidades sociais, comunicativas e comportamentais. O prejuízo da capacidade de empatia vem sendo apontado como um aspecto característico do endofenótipo dos TID. O presente estudo avaliou e comparou empatia em pessoas com TID e um grupo controle, através de tarefa de julgamento de expressões faciais básicas, contidas no Baralho da Empatia, instrumento desenvolvido pela pesquisadora. Foram avaliados 7 participantes com TID, do sexo masculino, com idades entre 6 e 15 anos, com QI mínimo de 70 (Wisc III) e que preenchiam critérios para diagnóstico de TID (DSM IV). Foram pareados por idade, sexo e inteligência com indivíduos com desenvolvimento normal. O grupo com TID errou significativamente mais que o controle, no julgamento de expressões faciais nas fotos (p< 0,001), nos desenhos (p=0,007) e nos dois testes quando analisado o desempenho total (p< 0,001). Houve diferença significativa entre controle e TID nas expressões de dúvida (p=0,031) e nojo (p=0,005) no Baralho de Desenhos, e nas Fotos, na expressão de nojo (p=0,018), sempre com maior índice de erros do grupo TID. Quando analisado o desempenho nas Fotos e Desenhos juntos, aparece diferença estatisticamente significante entre expressões de dúvida (p=0,012), nojo (p<0,001) e surpresa (p=0,006). Os resultados obtidos reforçam achados de pesquisas anteriores sobre o prejuízo da capacidade de empatia em pessoas com TID.

Cet ouvrage aborde la génération de grilles de Voronoï sous contrainte pour réduire les erreurs liées à la géométrie des cellules lors de la simulation réservoir. Les points de Voronoï sont optimisés en minimisant des fonctions objectif correspondant à différentes contraintes géométriques. L'originalité de cette approche est de pouvoir combiner les contraintes simultanément : - la qualité des cellules, en plaçant les points de Voronoï aux barycentres des cellules ; - le raffinement local, en fonction d'un champ de densité [rho], correspondant à la perméabilité, la vitesse ou la vorticité ; - l'anisotropie des cellules, en fonction d'un champ de matrice M contenant les trois vecteurs principaux de l'anisotropie, dont l'un est défini par le vecteur vitesse ou par le gradient stratigraphique ; - l'orientation des faces des cellules, en fonction d'un champ de matrice M contenant les trois vecteurs orthogonaux aux faces, dont l'un est défini par le vecteur vitesse ; - la conformité aux surfaces du modèle structural, failles et horizons ; - l'alignement des points de Voronoï le long des puits. La qualité des grilles générées est appréciée à partir de critères géométriques et de résultats de simulation comparés à des grilles fines de référence. Les résultats indiquent une amélioration de la géométrie, qui n'est pas systématiquement suivie d'une amélioration des résultats de simulation / Voronoi grids are generated under constraints to reduce the errors due to cells geometry during flow simulation in reservoirs. The Voronoi points are optimized by minimizing objective functions relevant to various geometrical constraints. An original feature of this approach is to combine simultaneously the constraints: - Cell quality, by placing the Voronoi points at the cell barycenters. - Local refinement according to a density field rho, relevant to permeability, velocity or vorticity. - Cell anisotropy according to a matrix field M built with the three principal vectors of the anisotropy, which one is defined by the velocity vector or by the stratigraphic gradient. - Faces orientation according to a matrix field M built with the three vectors orthogonal to the faces, which one is defined by the velocity vector. - Conformity to structural features, faults and horizons. - Voronoï points alignment along well path. The quality of the generated grids is assessed from geometrical criteria and from comparisons of flow simulation results with reference fine grids. Results show geometrical improvements, that are not necessarily followed by flow simulation results improvements

[pt] A identificação facial em vídeo é uma aplicação de grande interesse na comunidade cientifica e na indústria de segurança, impulsionando a busca por técnicas mais robustas e eficientes. Atualmente, no âmbito de reconhecimento facial, as técnicas de identificação frontal são as com melhor taxa de acerto quando comparadas com outras técnicas não frontais. Esse trabalho tem como objetivo principal buscar métodos de avaliar imagens em vídeo em busca de pessoas (rostos), avaliando se a qualidade da imagem está dentro de uma faixa aceitável que permita um algoritmo de reconhecimento facial frontal identificar os indivíduos. Propõem-se maneiras de diminuir a carga de processamento para permitir a avaliação do máximo número de indivíduos numa imagem sem afetar o desempenho em tempo real. Isso é feito através de uma análise da maior parte das técnicas utilizadas nos últimos anos e do estado da arte, compilando toda a informação para ser aplicada em um projeto que utiliza os pontos fortes de cada uma e compense suas deficiências. O resultado é uma plataforma multithread. Para avaliação do desempenho foram realizados testes de carga computacional com o uso de um vídeo público disponibilizado na AVSS (Advanced Video and Signal based Surveillance). Os resultados mostram que a arquitetura promove um melhor uso dos recursos computacionais, permitindo um uso de uma gama maior de algoritmos em cada segmento que compõe a arquitetura, podendo ser selecionados segundo critérios de qualidade da imagem e ambiente onde o vídeo é capturado. / [en] Face recognition in video is an application of great interest in the scientific community and in the surveillance industry, boosting the search for efficient and robust techniques. Nowadays, in the facial recognition field, the frontal identification techniques are those with the best hit ratio when compared with others non-frontal techniques. This work has as main objective seek for methods to evaluate images in video to look for people (faces), assessing if the image quality is in an acceptable range that allows a facial recognition algorithm to identify the individuals. It s proposed ways to decrease the processing load to allow a maximum number of individuals assessed in an image without affecting the real time performance. This is reached through analysis of most the techniques used in the last years and the state-of-the-art, compiling all information to be applied in a project that uses the strengths of each one and offset its shortcomings. The outcome is a multithread platform. Performance evaluation was performed through computational load tests by using public videos available in AVSS ( Advanced Video and Signal based Surveillance). The outcomes show that the architecture makes a better use of the computational resources, allowing use of a wide range of algorithms in every segment of the architecture that can be selected according to quality image and video environment criteria.