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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
111

Modelagem computacional para reconhecimento de emoções baseada na análise facial / Computational modeling for emotion recognition based on facial analysis

Giampaolo Luiz Libralon 24 November 2014 (has links)
As emoções são objeto de estudo não apenas da psicologia, mas também de diversas áreas como filosofia, psiquiatria, biologia, neurociências e, a partir da segunda metade do século XX, das ciências cognitivas. Várias teorias e modelos emocionais foram propostos, mas não existe consenso quanto à escolha de uma ou outra teoria ou modelo. Neste sentido, diversos pesquisadores argumentam que existe um conjunto de emoções básicas que foram preservadas durante o processo evolutivo, pois servem a propósitos específicos. Porém, quantas e quais são as emoções básicas aceitas ainda é um tópico em discussão. De modo geral, o modelo de emoções básicas mais difundido é o proposto por Paul Ekman, que afirma a existência de seis emoções: alegria, tristeza, medo, raiva, aversão e surpresa. Estudos também indicam que existe um pequeno conjunto de expressões faciais universais capaz de representar as seis emoções básicas. No contexto das interações homem-máquina, o relacionamento entre ambos vem se tornando progressivamente natural e social. Desta forma, à medida que as interfaces evoluem, a capacidade de interpretar sinais emocionais de interlocutores e reagir de acordo com eles de maneira apropriada é um desafio a ser superado. Embora os seres humanos utilizem diferentes maneiras para expressar emoções, existem evidências de que estas são mais precisamente descritas por expressões faciais. Assim, visando obter interfaces que propiciem interações mais realísticas e naturais, nesta tese foi desenvolvida uma modelagem computacional, baseada em princípios psicológicos e biológicos, que simula o sistema de reconhecimento emocional existente nos seres humanos. Diferentes etapas são utilizadas para identificar o estado emocional: a utilização de um mecanismo de pré-atenção visual, que rapidamente interpreta as prováveis emoções, a detecção das características faciais mais relevantes para o reconhecimento das expressões emocionais identificadas, e a análise de características geométricas da face para determinar o estado emocional final. Vários experimentos demonstraram que a modelagem proposta apresenta taxas de acerto elevadas, boa capacidade de generalização, e permite a interpretabilidade das características faciais encontradas. / Emotions are the object of study not only of psychology, but also of various research areas such as philosophy, psychiatry, biology, neuroscience and, from the second half of the twentieth century, the cognitive sciences. A number of emotional theories and models have been proposed, but there is no consensus on the choice of one or another of these models or theories. In this sense, several researchers argue that there is a set of basic emotions that have been preserved during the evolutionary process because they serve specific purposes. However, it is still a topic for discussion how many and which the accepted basic emotions are. In general, the model of basic emotions proposed by Paul Ekman, which asserts the existence of six emotions - happiness, sadness, fear, anger, disgust and surprise, is the most popular. Studies also indicate the existence of a small set of universal facial expressions related to the six basic emotions. In the context of human-machine interactions, the relationship between human beings and machines is becoming increasingly natural and social. Thus, as the interfaces evolve, the ability to interpret emotional signals of interlocutors and to react accordingly in an appropriate manner is a challenge to surpass. Even though emotions are expressed in different ways by human beings, there is evidence that they are more accurately described by facial expressions. In order to obtain interfaces that allow more natural and realistic interactions, a computational modeling based on psychological and biological principles was developed to simulate the emotional recognition system existing in human beings. It presents distinct steps to identify an emotional state: the use of a preattentive visual mechanism, which quickly interprets the most likely emotions, the detection of the most important facial features for recognition of the identified emotional expressions, and the analysis of geometric facial features to determine the final emotional state. A number of experiments demonstrated that the proposed computational modeling achieves high accuracy rates, good generalization performance, and allows the interpretability of the facial features revealed.
112

The ability of four-year-old children to recognize basic emotions represented by graphic symbols

Visser, Naomi Aletta 16 November 2007 (has links)
Emotions are an essential part of development. There is evidence that young children understand and express emotions through facial expressions. Correct identification and recognition of facial expressions is important to facilitate communication and social interaction. Emotions are represented in a wide variety of symbol sets and systems in Alternative and Augmentative Communication (AAC) to enable a person with little or no functional speech to express emotion. These symbols consist of a facial expression with facial features to distinguish between emotions. In spite of the importance of expressing and understanding emotions to facilitate communication, there is limited research on young children’s ability to recognize emotions represented by graphic symbols. The purpose of this study was to investigate the ability of typically developing fouryearold children to recognize basic emotions as represented by graphic symbols. In order to determine their ability to recognize emotions on graphic symbols, their ability to understand emotions had to be determined. Participants were then required to recognize four basic emotions (happy, sad, afraid, angry) represented by various graphic symbols, taken from PCS (Johnson, 1981), PICSYMS (Carlson, 1985) and Makaton (Grove&Walker, 1990). The purpose was to determine which graphic symbol the children recognized as representation of an emotion. Results showed that the emotion of happy was easier to recognize, which might be because it was the only emotion in the pleasure dimension of emotions. Sad, afraid and angry were more difficult to recognize which might be because they fall in the displeasure dimension. It is also evident from the findings that the facial features in the graphic symbol play an important part in conveying a specific emotion. The results that were obtained are discussed in relation to previous findings. Finally, recommendations for future use are made. / Dissertation (MA (Augumentative and Alternative Communication))--University of Pretoria, 2008. / Centre for Augmentative and Alternative Communication (CAAC) / MA / unrestricted
113

Effets de la dynamique temporelle sur le jugement de l'authenticité du sourire

Asselin, David 13 April 2021 (has links)
La capacité à exprimer autre chose sur le visage que l’expression faciale associée à l’émotion qui est ressentie n’est apparue que relativement tard dans la grande histoire de l’être humain. Alors que cette concordance était directe à l’aube de l’évolution humaine, elle aurait par la suite évolué en raison des bénéfices sociaux qu’elle procure à celui qui émet l’expression faciale. Encore aujourd’hui, la littérature nous donne un portrait nuancé sur le lien qui existe entre l’émotion ressentie et son expression faciale. D’un côté, plusieurs études nous indiquent qu’il existe une concordance entre ces deux processus (Gosselin, Kirouac, & Dore, 1995; Rosenberg & Ekman, 1994; Ruch, 1995) alors que de l’autre nous savons aussi que l’expression faciale peut très bien être contrôlée et trompeuse (O’Sullivan et al., 1988, Ekman, 1993; 2003). Il existe différents indices qui nous permettent de distinguer entre une expression faciale authentique et une expression faciale fausse. Parmi ceux-ci figurent les unités d’action faciale qui sont activées sur le visage lors de l’expression faciale, leur symétrie et leur dynamique temporelle, toutes mesurées à l'aide du Facial Action Coding System (Ekman & Friesen, 1978; Ekman, Friesen & Hager, 2002). L’objectif principal de cette thèse sera d’évaluer la sensibilité de l’être humain à la dynamique temporelle du sourire, ainsi que son effet sur le jugement d’authenticité. Les résultats des études 1 à 3 indiquent que les participants sont bien sensibles à la dynamique temporelle, et qu’ils l’utilisent pour juger correctement l’authenticité du sourire, du moins lorsque la durée des phases de relâchement, ou les phases d’amorce et de relâchement simultanément varie. Nos participants ne semblent pas utiliser la dynamique temporelle pour juger de l’authenticité du sourire même s’ils sont en mesure de bien juger les différences temporelles dans la phase d’amorce. L’étude 4 a été réalisée afin de valider la méthode de fabrication des stimuli utilisée dans les études précédente, et confirme que celle-ci n’a pas eu d’effet sur les résultats. Enfin, l’étude 5 a été réalisée dans le but d’examiner davantage le lien unissant la dynamique temporelle au jugement d’authenticité grâce à deux tâches de jugement; La première voulant examiner le jugement de la durée de sourires, alors que la seconde examine le jugement de l’authenticité. Plutôt que d’utiliser une échelle de type Likert telle que dans les études 1 et 4, nous avons opté pour une méthode d’estimation de la magnitude, dans le but d’examiner les habiletés de manière intra individuelles de nos participants. Celle-ci montre qu’au niveau individuel, les participants qui arrivent à mieux juger les changements dans la durée des phases du sourire n’arrivent pas nécessairement à mieux juger l’authenticité du sourire. Dans leur ensemble, nos résultats contribuent à la compréhension que nous avons du lien unissant la dynamique temporelle et le jugement de l’authenticité du sourire, et permettent de solidifier la fondation empirique sur lequel pourront construire les études futures du domaine.
114

Los estudios del cuerpo humano por Leonardo da Vinci para su obra artística

Deluca Sánchez , Giulia 07 July 2021 (has links)
Tras la época oscura de la Edad Media, en Italia durante los años 1400 surge el Renacimiento, como una búsqueda de regresar a una cultura de la antigua Roma y Grecia y tener mayor interés por el ser humano. Este resurgimiento cultural se vio reflejado también en el arte. Según el autor Argan (2001), los artistas renacentistas volvieron a pintar al hombre y la naturaleza, que durante la Edad Media habían dejado de ser los protagonistas de las obras. Asimismo, Riutort (2010), afirma que pintores y escultores empezaron a estudiar el cuerpo humano, entre ellos destaca Leonardo da Vinci. Quien es considero para muchos autores como el referente principal de anatomía artística, ya que sus descubrimientos siguen siendo importantes temas de estudio en diferentes en el campo del arte y la medicina. Entre los estudios realizados por Leonardo da Vinci, destacan el de proporcionalidad del cuerpo humano, músculos, movimiento de articulaciones y la expresividad facial. Mediante la investigación de dichos estudios, se realizo una colección en donde destaquen las formas, siluetas y texturas inspiradas en las obras de Leonardo da Vinci. / After the dark ages of the Middle Ages, the Renaissance arose in Italy in the 1400s as a quest for a return to the culture of ancient Rome and Greece and a greater concern for the human being. This cultural revival was also reflected in art. According to the author Argan (2001), Renaissance artists returned to painting man and nature, which during the Middle Ages had ceased to be the protagonists of the works. Likewise, Riutort (2010), states that painters and sculptors began to study the human body, among them Leonardo da Vinci. He is considered by many authors as the main reference of artistic anatomy, since his discoveries are still important subjects of study in different fields of art and medicine. Among the studies carried out by Leonardo da Vinci, the proportionality of the human body, muscles, movement of joints and facial expressiveness stand out. Through the investigation of these studies, a collection was made in which the forms, silhouettes and textures inspired by the works of Leonardo da Vinci stand out. / Trabajo de investigación
115

Children's Recognition of Pride: An Experimental Approach

Garcia, Darren Jason 01 December 2013 (has links) (PDF)
Pride is elicited when a child takes credit for an achievement or exceeds a socially valued standard or expectation. Evidence suggests that pride has a distinct nonverbal expression that is recognized by adults across cultures (Tracy & Robins, 2004). Research examining when children recognize pride has yielded age discrepancies between studies that use forced-choice response formats and those that use spontaneous-response formats. Differences in children's ability to use and comprehend language may account for some of these differences. The purpose of this thesis was to examine the age at which children reliably recognize pride, while minimizing the need for children to rely on their linguistic or verbal abilities. The present experiment used an experimental approach to examine when children reliably recognize pride. One hundred forty-four children between the ages of 2.5- and 6.5-years participated in one of three experimental conditions: Exceed Standard, Fail Standard or No Standard. Frequency of pride recognition in the Exceed Standard condition was compared to frequencies of pride recognition in the Fail Standard and No Standard conditions. Results revealed a developmental progression of pride recognition in which children first begin showing nonverbal pride behaviors at about 2.5- to 3.5-years, acquire the ability to apply a label to the nonverbal pride expression between 3.5- and 4.5-years of age, and come to recognize their own emotional experience as pride in an achievement situation between 4.5- and 5.5-years of age.
116

A Computational Model of the Production and Perception ofFacial Expressions of Basic and Compound Emotions

Du, Shichuan 29 December 2014 (has links)
No description available.
117

A facial animation model for expressive audio-visual speech

Somasundaram, Arunachalam 21 September 2006 (has links)
No description available.
118

Electronic Customer Knowledge Management Systems : a multimodal interaction approach : an empirical investigation into the role of the multimodal interaction metaphors to improve usability of Electronic Customer Knowledge Management Systems (ECKMS) and increase the user's trust, knowledge and acceptance

Alotaibi, Mutlaq Bader Gublan January 2009 (has links)
There has been an increasing demand for commercial organisations to foster real-time interaction with customers, because harnessing customer competencies has been shown to be a major contributor towards various benefits, such as growth, innovation and competition. This may drive organisations to embrace the development of multimodal interaction and complement Electronic Customer Knowledge Management Systems (E-CKMS) with metaphors of audio-visual nature. Although the implementation of E-CKMS encounters several challenges, such as lack of trust and information overload, few empirical studies were devoted to assess the role of audio-visual metaphors, and investigate whether these technologies can be put into practice. Therefore, this thesis describes a comparative evaluation study carried out to examine the implication of incorporating multimodal metaphors into E-CKMS interfaces on not only usability of E-CKMS, but also the user's trust, knowledge and acceptance. An experimental E-CKMS platform was implemented with three different modes of interaction: Visual-only E-CKMS (VCKMS) with text and graphics, Multimodal E-CKMS (MCKMS) with speech, earcons and auditory icons and Avatar-enhanced multimodal E-CKMS (ACKMS). The three platforms were evaluated by three independent groups of twenty participants each (total=60) who carried out eight common tasks of increasing complexity and design based on three different styles. Another dependent group of forty-eight participants (n=48) was instructed to interact with the systems under similar usability conditions by performing six common tasks of two styles, and fill a questionnaire devised to measure the aspects of user acceptance. The results therein revealed that ACKMS was more usable and acceptable than both MCKMS and VCKMS, whereas MCKMS was more usable than VCKMS, but less acceptable. Inferential Statistics indicated that these results were statistically significant.
119

Understanding the Expressive Cartoon Drawings of a Student with Autism Spectrum Disorder

Collins, Michael S 01 January 2017 (has links)
This study focuses on the highly expressive comic drawings of Amy, a child with autism. This study connects larger fields of research: the study of how people with autism spectrum disorder [ASD] process faces and emotions; and, research about artists with ASD. Amy's understanding of emotion was analyzed by asking her to view and identify humans and cartoon characters expressing different emotions. Her ability to illustrate emotion is tested by asking her to respond to various drawing prompts. The study concluded that Amy has difficulty identifying the emotions of humans and cartoons, but she does have the ability to illustrate characters that express a range of emotions. This individual case study shows that students with autism were able to process visual expressions of emotion with a high degree of accuracy. The results provide art educators a model with which to investigate how their students with autism process emotional expression.
120

Communication chez les primates non humains : étude des asymétries dans la production d'expressions oro-faciales / Communication in non-human primates : studying asymmetries during the production of oro-facial expressions

Wallez, Catherine 11 October 2012 (has links)
L'examen des asymétries oro-faciales fournit un indice indirect et fiable pour déterminer la spécialisation hémisphérique des processus liés à la communication socio-émotionnelle chez les primates non humains. Cependant, à ce jour, peu d'études ont été réalisées et les théories formulées chez l'homme sont peu consensuelles. Afin de contribuer à la question de la latéralisation cérébrale des processus cognitivo-émotionnels chez le primate, quatre études expérimentales ont été réalisées au cours de cette thèse. Tout d'abord, deux méthodes ont été utilisées pour mesurer les asymétries oro-faciales dans une population de babouins adultes (une méthode morphométrique et une méthode dite des « chimères »). Une spécialisation hémisphérique droite dominante pour le traitement des émotions négatives a été notée. Une troisième étude a démontré, pour la première fois, une asymétrie oro-faciale au niveau populationnel chez des jeunes macaques et babouins. Enfin, une dernière étude a été réalisée chez des chimpanzés afin de tester la robustesse d'une recherche qui avait mis en évidence une différence d'asymétrie selon la fonction communicative intentionnelle (hémisphère gauche) vs. émotionnelle (hémisphère droit) des vocalisations. Les résultats ont confirmé ceux de la première étude et permettent de discuter des hypothèses concernant l'origine de l'évolution du langage. Ces travaux sont discutés à la lumière des recherches récentes concernant de nombreuses espèces animales. Ils apportent des connaissances nouvelles pour appréhender la phylogénèse de la spécialisation hémisphérique des processus associés à la communication verbale et non verbale chez l'homme. / The study of oro-facial asymmetries offers an indirect and suitable index to determine the hemispheric specialization of the processes associated to socio-emotional communication in non-human primates. However, few studies have been made in this domain and the available theories in humans are in part contradictory. In order to contribute to this field, i.e., hemispheric specialization of cognitive and emotional processing in primates, four experimental studies have been carried out during this doctorate. Firstly, two methods have been used to assess oro-facial asymmetries in adult baboons (a morphometric one and a free viewing of chimeric faces). A right hemispheric specialization for negative emotions was noticed. A third study demonstrated for the first time a population-level hemispheric specialization for the production of emotions in infant macaques and baboons. A last study tested the robustness of previous findings in chimpanzees concerning differences of hemispheric lateralization patterns depending on the communicative function of the vocalizations: intentional (left hemisphere) vs emotional (right hemisphere). Results confirmed the previous conclusions and allowed to discuss hypotheses about the origin of the evolution of language (speech). These collective findings are discussed within the context of the phylogeny of hemispheric specialization mechanisms underlying verbal and nonverbal communication in humans.

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