903 resultados para Audio-visual content classification
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Deep sea manganese nodules are considered as important natural resources for the future because of their Ni, Cu and Co contents. Their different shapes cannot be correlated clearly with their chemical composition. Surface constitution, however, can be associated with the metal contents. A classification of the nodules is suggested on the basis of these results. The iron content of the nodules strikingly shows relations to the physical properties (e.g. density and porosity). The method of density-measurement is the reason for this covariance. The investigation of freeze-dried nodular substance does not give this result. The Fe-rich nodules lose more hydration water than the Fe-poor ones during heat drying. The reason for this effect is the different crystallinity, respectively the particle size. The mean particle size is calculated on the basis of geometrical models. The X-ray-diffraction analysis proves the variation of crystallinity in connection with the Fe-content, too. The internal nodular textures also show characteristic distinctions.
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Authigenic carbonate deposits have been sampled with the remotely operated vehicle 'MARUM-QUEST 4000 m' from five methane seeps between 731 and 1823 m water depth along the convergent Makran continental margin, offshore Pakistan (northern Arabian Sea). Two seeps on the upper slope are located within the oxygen minimum zone (OMZ; ca. 100 to 1100 m water depth), the other sites are situated in oxygenated water below the OMZ (below 1100 m water depth). The carbonate deposits vary with regard to their spatial extent, sedimentary fabrics, and associated seep fauna: Within the OMZ, carbonates are spatially restricted and associated with microbial mats, whereas in the oxygenated zone below the OMZ extensive carbonate crusts are exposed on the seafloor with abundant metazoans (bathymodiolin mussels, tube worms, galatheid crabs). Aragonite and Mg-calcite are the dominant carbonate minerals, forming common early diagenetic microcrystalline cement and clotted to radial-fibrous cement. The delta18O carbonate values range from 1.3 to 4.2 per mil V-PDB, indicating carbonate precipitation at ambient bottom-water temperature in shallow sediment depth. Extremely low delta13Ccarbonate values (as low - 54.6per mil V-PDB) point to anaerobic oxidation of methane (AOM) as trigger for carbonate precipitation, with biogenic methane as dominant carbon source. Prevalence of biogenic methane in the seepage gas is corroborated by delta13C methane values ranging from - 70.3 to - 66.7per mil V-PDB, and also by back-calculations considering delta 13C methane values of carbonate and incorporated lipid biomarkers.
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This dissertation focuses on two vital challenges in relation to whale acoustic signals: detection and classification.
In detection, we evaluated the influence of the uncertain ocean environment on the spectrogram-based detector, and derived the likelihood ratio of the proposed Short Time Fourier Transform detector. Experimental results showed that the proposed detector outperforms detectors based on the spectrogram. The proposed detector is more sensitive to environmental changes because it includes phase information.
In classification, our focus is on finding a robust and sparse representation of whale vocalizations. Because whale vocalizations can be modeled as polynomial phase signals, we can represent the whale calls by their polynomial phase coefficients. In this dissertation, we used the Weyl transform to capture chirp rate information, and used a two dimensional feature set to represent whale vocalizations globally. Experimental results showed that our Weyl feature set outperforms chirplet coefficients and MFCC (Mel Frequency Cepstral Coefficients) when applied to our collected data.
Since whale vocalizations can be represented by polynomial phase coefficients, it is plausible that the signals lie on a manifold parameterized by these coefficients. We also studied the intrinsic structure of high dimensional whale data by exploiting its geometry. Experimental results showed that nonlinear mappings such as Laplacian Eigenmap and ISOMAP outperform linear mappings such as PCA and MDS, suggesting that the whale acoustic data is nonlinear.
We also explored deep learning algorithms on whale acoustic data. We built each layer as convolutions with either a PCA filter bank (PCANet) or a DCT filter bank (DCTNet). With the DCT filter bank, each layer has different a time-frequency scale representation, and from this, one can extract different physical information. Experimental results showed that our PCANet and DCTNet achieve high classification rate on the whale vocalization data set. The word error rate of the DCTNet feature is similar to the MFSC in speech recognition tasks, suggesting that the convolutional network is able to reveal acoustic content of speech signals.
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El artículo analiza la figura del prosumidor desde los estudios visuales a partir de la combinación de la teoría de los actos de habla y los nuevos medios. El objetivo es evaluar si la distinción entre productores y consumidores, estrategias y tácticas de Michel de Certeau continúa siendo operativa en las interfaces gráficas de la cultura global de la información de Scott Lash. Para ello distingue dos tipos de performatividad de los actos de habla: la performatividad top-down del software, y la bottom-up de los juegos del lenguaje y las formas de vida. Estos tipos se aplican al análisis del discurso de los eslóganes que aparecen en los sitios web de las iniciativas “open” y de economía colaborativa, ya que las primeras están dedicadas a la producción de bienes inmateriales y las segundas a la producción de bienes materiales. El desarrollo muestra cómo los dos tipos de performatividad transforman el análisis textual de los estudios literarios y cinematográficos en una metodología capaz de investigar acciones materiales, humanas y no humanas. Las conclusiones describen el surgimiento de nuevas convenciones narrativas de poder y control ajenas a la ficción que apuntan a una “DIY society”.
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The Semantic Annotation component is a software application that provides support for automated text classification, a process grounded in a cohesion-centered representation of discourse that facilitates topic extraction. The component enables the semantic meta-annotation of text resources, including automated classification, thus facilitating information retrieval within the RAGE ecosystem. It is available in the ReaderBench framework (http://readerbench.com/) which integrates advanced Natural Language Processing (NLP) techniques. The component makes use of Cohesion Network Analysis (CNA) in order to ensure an in-depth representation of discourse, useful for mining keywords and performing automated text categorization. Our component automatically classifies documents into the categories provided by the ACM Computing Classification System (http://dl.acm.org/ccs_flat.cfm), but also into the categories from a high level serious games categorization provisionally developed by RAGE. English and French languages are already covered by the provided web service, whereas the entire framework can be extended in order to support additional languages.
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The development of Latin American cinema in the 1960s was underwritten by a number of key texts that outlined the aesthetic and political direction of individual filmmakers and collectives (Solanas and Getino, 1969; Rocha, 1965; Espinosa, 1969). Although asserting the specificity of Latin American culture, the theoretical foundations of its New Wave influenced oppositional filmmaking way beyond its own regional boundaries. This chapter looks at how movements in British art cinema, especially the Black Audio Film Collective, were inspired and propelled by the theories behind New Latin American cinema. Facilitated by English translations in journals such as Jump Cut in the early ‘80s, Cuban and Argentine cinematic manifestoes provided a radical alternative to the traditional language of film theory available to filmmakers in Europe and works such as Signs of Empire (1983-4); Handsworth Songs (1986) and Seven Songs for Malcolm X (1993) grew out of this trans-continental exchange. The Black Audio Film Collective represented a merging of politics, popular culture, and art that was, at once, oppositional and melodic. Fusing postcolonial discourse with pop music, the avant-garde and re-imaginings of subalternity, the work of ‘The Collective’ provides us with a useful example of how British art cinema has drawn from theoretical foundations formed outside of Europe and the West. As this chapter will argue however, the Black Audio Film Collective’s work can also be read as a reaction to the specificity of British socio-politics of the ‘80s and ‘90s. Its engagement with the aesthetico-political strategies of Latin American cinema, then, undercut what was a solidly British project, rooted in (post)colonial history and emerging ideas of disaporic identity. If the propulsive thrust of The Black Audio Film Collective’s art was shaped by Third Cinema, its images and concerns were self-consciously British.
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Computer games are significant since they embody our youngsters’ engagement with contemporary culture, including both play and education. These games rely heavily on visuals, systems of sign and expression based on concepts and principles of Art and Architecture. We are researching a new genre of computer games, ‘Educational Immersive Environments’ (EIEs) to provide educational materials suitable for the school classroom. Close collaboration with subject teachers is necessary, but we feel a specific need to engage with the practicing artist, the art theoretician and historian. Our EIEs are loaded with multimedia (but especially visual) signs which act to direct the learner and provide the ‘game-play’ experience forming semiotic systems. We suggest the hypothesis that computer games are a space of deconstruction and reconstruction (DeRe): When players enter the game their physical world and their culture is torn apart; they move in a semiotic system which serves to reconstruct an alternate reality where disbelief is suspended. The semiotic system draws heavily on visuals which direct the players’ interactions and produce motivating gameplay. These can establish a reconstructed culture and emerging game narrative. We have recently tested our hypothesis and have used this in developing design principles for computer game designers. Yet there are outstanding issues concerning the nature of the visuals used in computer games, and so questions for contemporary artists. Currently, the computer game industry employs artists in a ‘classical’ role in production of concept sketches, storyboards and 3D content. But this is based on a specification from the client which restricts the artist in intellectual freedom. Our DeRe hypothesis places the artist at the generative centre, to inform the game designer how art may inform our DeRe semiotic spaces. This must of course begin with the artists’ understanding of DeRe in this time when our ‘identities are becoming increasingly fractured, networked, virtualized and distributed’ We hope to persuade artists to engage with the medium of computer game technology to explore these issues. In particular, we pose several questions to the artist: (i) How can particular ‘periods’ in art history be used to inform the design of computer games? (ii) How can specific artistic elements or devices be used to design ‘signs’ to guide the player through the game? (iii) How can visual material be integrated with other semiotic strata such as text and audio?
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Purpose: It is important to establish a differential diagnosis between the different types of nystagmus, in order to give the appropriate clinical approach to every situation and to improve visual acuity. The nystagmus is normally blocked when the eyes are positioned in a particular way. This makes the child adopt a posture of ocular torticollis that reduces the nistagmiformes movements, improving the vision in this position. A way to promote the blocking of the nystagmic movements is by using prismatic lenses with opposite bases, to block or minimize the oscillatory movements. This results in a vision improvement and it reduces the anomalous head position. There is limited research on the visual results in children with nystagmus after using prisms with opposing bases. Our aim is to describe the impact on the visual acuity (VA ) of theprescription prism lenses in a nystagmus patient starting at 3 months of age. Methods: Case report on thirty month old caucasian male infant, with normal growth and development for their age, with an early onset of horizontal nystagmus at 3 months of age. Ophthalmic examination included slit lamp examination, fundus, refractive study, electrophysiological and magnetic resonance tests, measurement of VA over time with the Teller Acuity Cards (TAC ) in the distance agreed for the age. At age ten months, the mother noted a persistent turn to the right of the child’s head, which became increasingly more severe along the months. There’s no oscillopcia. At 24 months, an atropine refraction showed the following refractive error: 0D.: -1,50, OS: -0,50 and prismatic lens adapting OD 8 Δ nasal base and OE 8 Δ temporal base. Results: Thirty month old child, with adequate development for their age, with onset of idiopatic horizontal nystagmus, at 3 months of age. Normal ocular fundus and magnetic ressoance without alterations, sub-normal results in electrophysiological tests and VA with values below normal for age. At 6 months OD 20/300; OE 20/400; OU 20/300. At 9 months OD 20/250; OE 20/300; OU 20/150 (TAC a 38 cm). At 18 months OD 20/200; OE 20/100; OU 20/80 (TAC at 38 cm), when the head is turned to the right and the eyes in levoversão, the nystagmus decreases in a “neutral” area. At 24 month, with the prismatic glasses, OD 20/200 OE 20/100, OU20/80 (TAC at 54 cm, reference value is 20/30 – 20/100 para OU e 20/40 – 20/100 monocular), there was an increase in the visual acuity. The child did visual stimulation with multimedia devices and using glasses. After adaptation of prisms: at 30 months VA (with Cambridge cards) OD e OE = 6/18. The child improved the VA and reduced the anomalous head position. There is also improvement in mobility and fine motricity. Conclusion: Prisms with opposing bases., were used in the treatment of idiopathic nystagmus. Said prisms were adapted to reduce the skewed position of the head, and to improve VA and binocular function. Monitoring of visual acuity and visual stimulation was done using electronic devices. Following the use of prismatic, the patient improved significantly VA and the anomalous head position was reduced.
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This article discusses the potential of audio games based on the evaluation of three projects: a story-driven audio role-playing game (RPG), an interactive audiobook with RPG elements, and a set of casual sound-based games. The potential is understood, both in popularity and playability terms. The first factor is connected to the degree of players’ interest, while the second one to the degree of their engagement in sound-based game worlds. Although presented projects are embedded within the landscape of past and contemporary audio games and gaming platforms, the authors reach into the near future, concluding with possible development directions for this non-visual interactive entertainment.
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We propose a study of the mathematical properties of voice as an audio signal -- This work includes signals in which the channel conditions are not ideal for emotion recognition -- Multiresolution analysis- discrete wavelet transform – was performed through the use of Daubechies Wavelet Family (Db1-Haar, Db6, Db8, Db10) allowing the decomposition of the initial audio signal into sets of coefficients on which a set of features was extracted and analyzed statistically in order to differentiate emotional states -- ANNs proved to be a system that allows an appropriate classification of such states -- This study shows that the extracted features using wavelet decomposition are enough to analyze and extract emotional content in audio signals presenting a high accuracy rate in classification of emotional states without the need to use other kinds of classical frequency-time features -- Accordingly, this paper seeks to characterize mathematically the six basic emotions in humans: boredom, disgust, happiness, anxiety, anger and sadness, also included the neutrality, for a total of seven states to identify
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A utilização das TIC ocupam um lugar cada vez mais importante nas nossas escolas, marcado sobretudo pela evolução das tecnologias e pela utilização em contexto educativo de muitas ferramentas da Web 2.0. Esse facto é muito notório na disciplina de Educação Visual e Tecnológica, de carácter eminentemente prático, onde é permitido explorar várias ferramentas digitais para abordagem de conteúdos da disciplina e para a criação de produtos gráficos e plásticos. Com o aparecimento da Web 2.0 e a disponibilização de milhares de novas ferramentas digitais aos utilizadores da Internet, estimula-se um interesse cada vez maior na adoção de metodologias e estratégias com recurso a estes media e que suportem uma aprendizagem mais eficaz e motivadora para os alunos, articulando-se os suportes tradicionais de EVT com os novos media digitais. Neste contexto, o presente estudo é o resultado duma investigação-ação realizada no âmbito do Programa Doutoral em Multimédia em Educação da Universidade de Aveiro onde se implementou a integração de ferramentas da Web, Web 2.0 e Software Livre em contexto educativo na disciplina de EVT, na qual poderiam ser utilizadas tanto as técnicas tradicionais de realização mais usuais na disciplina como a integração e articulação com as ferramentas digitais, suportadas por software livre (e outros de utilização gratuita), a Web e a Web 2.0 para suporte ao ensino e aprendizagem dos diversos conteúdos e áreas de exploração da disciplina. Este estudo, desenhado em três ciclos, envolveu num primeiro momento a constituição de uma comunidade de prática de professores alargada, sendo criadas seis turmas de formação que reuniram um total de 112 professores que pretendiam integrar as ferramentas digitais em EVT. Para além da pesquisa, análise, seleção e catalogação destas 430 ferramentas digitais recenseadas, produziram-se 371 manuais de apoio à utilização das mesmas, sendo estes recursos disponibilizados no espaço do EVTdigital. Num segundo ciclo, decorrente da avaliação realizada, foi criada a distribuição EVTux para simplificar o acesso e utilização das ferramentas digitais em contexto de EVT. Finalmente, o terceiro ciclo, decorre da eliminação da disciplina de EVT do currículo do 2º ciclo do ensino básico e a sua substituição por duas novas disciplinas, tendo-se realizada a respetiva análise de conteúdo das metas curriculares e produzido a aplicação As ferramentas digitais do Mundo Visual, concebida para contextualizar e indexar as ferramentas digitais selecionadas para a nova disciplina de Educação Visual.Os resultados deste estudo apontam claramente para a possibilidade de integrar na disciplina de Educação Visual e Tecnológica (ou no presente momento, em Educação Visual) ferramentas digitais para abordagem aos conteúdos e áreas de exploração, bem como a possibilidade de se constituírem facilmente comunidades de prática (como foi o caso) que possam colaborar na catalogação destas ferramentas no contexto específico da disciplina e para a necessidade sentida pelos professores em obter informação e formação que os possa atualizar quanto à integração das TIC no currículo. Apresentam-se, ainda, as limitações deste estudo que passaram sobretudo pelo impacto negativo que a eliminação da disciplina provocou na motivação dos docentes e a sua consequente participação no decorrer de algumas fases do trabalho, e ainda da dificuldade de gestão de uma equipa de professores colaboradores tão numerosa e diversificada. Nesse sentido, são também apresentadas sugestões para estudos futuros.
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Este estudo pretendeu examinar a importância dos estímulos auditivo (interpre-tação vocal do cantor) e visual (expressão facial do cantor) na perceção de emo-ções pelo público de uma performance de canto. Para tal, foram gravados, atra-vés de vídeo e áudio, dois cantores a interpretar pequenas frases melódicas com a intenção de expressar, isoladamente, as seis emoções básicas: alegria, tristeza, raiva, medo, surpresa e nojo. Para validar a expressividade dos canto-res, foi medida, através de eletromiografia, a atividade dos músculos faciais du-rante a performance da emoção e foram apresentadas as gravações áudio a um painel de especialistas que as caracterizaram em termos acústicos. Com base nas gravações audiovisuais dos cantores, foi criado um teste percetual no qual se pretendia que o ouvinte reconhecesse a emoção comunicada a partir apenas do áudio, apenas do vídeo, ou ambos. Comparando as respostas dadas, os re-sultados evidenciaram que o estímulo visual é mais eficaz do que o auditivo, e que a junção dos dois estímulos é a modalidade mais eficiente na perceção de emoções pelo público de uma performance de canto.
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The effect of varying states of visual deprivation on the development of the optic lobes and cerebral hemispheres has been studied in the chick where the visual pathways are totally crossed over. Unilateral eye extirpation of the new hatched chick resulted in arrested development of the contralateral but not ipsilateral lobe, as measured by weight, protein content and acetylcholinesterase activity. Similar effects but of smaller magnitude were observed in the cerebral hemispheres. Histologic and enzymic evidence revealed the absence of significant degeneration in the optic lobe contralateral to an eye removed 17 days previously. These results were observed in the optic lobes of operated animals maintained either in light of in darkness between 3 and 17 days after hatch. However, in the inpaired cerebral hemispheres, differences could only be detected in birds kept the light. The effects of unilateral eyelid suturing on the development of chick brain regions were also examined. In this group, all asymmetrical differences observed within paired brain regions were totally light dependent and confined to the cerebral hemispheres. The hemisphere contralateral to the sutured eye weighed less and had less acetylcholinesterase activity than its paired hemisphere. The cerebral hemispheres of monocularly treated birds manifested effects of similar magnitude whether the treatment was enucleation or suturing. This suggests that the complete development of the associative centers in avian cerebral hemispheres is dependent on both intact innervation and on the information content of the visual input. © 1969.
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Increasing the size of training data in many computer vision tasks has shown to be very effective. Using large scale image datasets (e.g. ImageNet) with simple learning techniques (e.g. linear classifiers) one can achieve state-of-the-art performance in object recognition compared to sophisticated learning techniques on smaller image sets. Semantic search on visual data has become very popular. There are billions of images on the internet and the number is increasing every day. Dealing with large scale image sets is intense per se. They take a significant amount of memory that makes it impossible to process the images with complex algorithms on single CPU machines. Finding an efficient image representation can be a key to attack this problem. A representation being efficient is not enough for image understanding. It should be comprehensive and rich in carrying semantic information. In this proposal we develop an approach to computing binary codes that provide a rich and efficient image representation. We demonstrate several tasks in which binary features can be very effective. We show how binary features can speed up large scale image classification. We present learning techniques to learn the binary features from supervised image set (With different types of semantic supervision; class labels, textual descriptions). We propose several problems that are very important in finding and using efficient image representation.
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International audience