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- MyTv: sistema personalizado de televisãoPublication . Ferreira, João; Jesus, Rui; Abrantes, ArnaldoAbordam-se os requisitos gerais de um sistema personalizado de televisão, no qual os utilizadores registados seriam alertados de programas interessantes, existentes no fluxo de programas, disponíveis num sistema de televisão por cabo.
- Terceira geração de sistemas de pesquisa de informaçãoPublication . Ferreira, João; Jesus, Rui; Abrantes, ArnaldoPretende-se discutir e fundamentar um conjunto de ideias necessárias para o desenvolvimento de sistemas de pesquisa com o objectivo de melhorar o desempenho dos mesmos. Assuntos como a personalização, perfil, interfaces de ajuda, uso de sistemas de classificação e contextualização da pesquisa são analisados e discutidos numa abordagem que permite integrar de uma forma unificada as suas potencialidades.
- Unveiling the hand of a 19th century artist with binary image classification and bag-of-featuresPublication . Montagner, Cristina; Jesus, Rui; Correia, Nuno; Melo, Maria J.; Villarigues, Marcia; Macedo, Rita; Freitas, Helena deThe shape, orientation and distribution of brushstrokes are distinctive markers left by the artist on the surface of a painting. Consequently, they are useful as additional evidence to decide on issues of attribution and authenticity. This paper proposes an image classification algorithm for the paintings of Amadeo de Souza-Cardoso, a modern Portuguese artist who is at the top of the Portuguese police’s list of forged artists. The proposed system is based on a binary classification using bag-of-features (SIFT descriptors and a Gabor filter) for image representation. Experimental results using the algorithm show that the classification of the paintings by extracting brushstroke information is very promising.
- Exploring the behavior of the player to change the course of a gamePublication . Beleza Sousa, João; Jesus, RuiThis paper proposes and discusses a horse racing game which explores the user behavior when playing, to change the gameplay. The game includes a module to capture and analyze, in real time, the body movement and the audio produced by the player. The paper describes the rational and design principles for the game and presents the main issues of the study conducted during the development of the game.
- Methods for automatic and assisted image annotationPublication . Jesus, Rui; Abrantes, Arnaldo; Correia, NunoPersonal memories composed of digital pictures are very popular at the moment. To retrieve these media items annotation is required. During the last years, several approaches have been proposed in order to overcome the image annotation problem. This paper presents our proposals to address this problem. Automatic and semi-automatic learning methods for semantic concepts are presented. The automatic method is based on semantic concepts estimated using visual content, context metadata and audio information. The semi-automatic method is based on results provided by a computer game. The paper describes our proposals and presents their evaluations.
- Sistema para pesquisa de imagens com retroacção de relevânciaPublication . Jesus, Rui; Abrantes, Arnaldo; Marques, Jorge S.Recentemente, a retroacção de relevância tem sido utilizada para melhorar o desempenho dos sistemas de pesquisa em base de dados de imagens. Este artigo apresenta um método de Retroacção de Relevância baseado no classificador de Mínimos Quadrados Regularizado e numa técnica de selecção de imagens que permite aumentar a capacidade de aprendizagem do método. São apresentados resultados de testes experimentais.
- Features combination for art authentication studies: brushstroke and materials analysis of Amadeo de Souza-CardosoPublication . Montagner, Cristina; Jesus, Rui; Correia, Nuno; Vilarigues, Márcia; Macedo, Rita; Melo, Maria JoãoThis work presents a tool to support authentication studies of paintings attributed to the modernist Portuguese artist Amadeo de Souza-Cardoso (1887-1918). The strategy adopted was to quantify and combine the information extracted from the analysis of the brushstroke with information on the pigments present in the paintings. The brushstroke analysis was performed combining Gabor filter and Scale Invariant Feature Transform. Hyperspectral imaging and elemental analysis were used to compare the materials in the painting with those present in a database of oil paint tubes used by the artist. The outputs of the tool are a quantitative indicator for authenticity, and a mapping image that indicates the areas where materials not coherent with Amadeo's palette were detected, if any. This output is a simple and effective way of assessing the results of the system. The method was tested in twelve paintings obtaining promising results.
- Gamifying the visit to places with valuable landscapesPublication . Jesus, Rui; Conceição, Catarina; Lopes, GonçaloThe landscape, in general, is full of meaning and has been studied over time by experts in different fields. In 1992, the landscape was considered a World Heritage Site with the designation of "Cultural Landscape". Despite this relevance, in many regions, there are places with valuable landscapes that are unknown to most of the population. This paper describes a mobile tool for finding and sharing places with valuable landscapes, which includes gamification components to motivate users to search for new places and share them. It is also presented an evaluation of the tool, in terms of user experience and including the assessment of gamification features. The tests were carried out in the Cultural Landscape of Sintra, considered world heritage since 1995.
- Arrayed graphene enhanced surface plasmon resonance for sensing applicationsPublication . Fantoni, Alessandro; Vygranenko, Yuri; Maçarico, António; Serafinelli, Caterina; Fernandes, Miguel; Mansour, Rima; Jesus, Rui; Vieira, ManuelaCombination of carbon-based nanomaterials (CNMs) with AuNPs has been demonstrated to enhance the LSPR response and facilitate the functionalization with specific and selective antibodies. Also, the introduction of CNMs in the plasmonic layer allows tuning of the LSPR central frequency. Joining the double dependence of the LSPR on the MNPs size and the presence of CNMs, it is possible to create a set of plasmonic layers whose LSPR wavelengths are distributed in a spectral range of few tenth of nanometers. This consideration paves the way to an LSPR sensor with an arrayed structure, where each element maximizes its specific LSPR at its own wavelength. Illumination with a broad light source produces a different response in each one of the elements. The working process underlying the sensing operation is that each element of the sensor array acts like a band-stop optical filter for a specific wavelength. The output can be extracted by the application of an image analysis approach to the spatially modulated light crossing the sensor area, based on a color recognition algorithm. A change in the refractive index over the sensor array will shift the rejection band of the sensing elements. An automatized method for color recognition can support the analysis of the refractive index variations yielding the final sensor output. A figure of merit, highlighting the LSPR central wavelength and spectral extension for different LSPR configurations, is also obtained for different sizes of the AuNPs and different flavors of CNMs.
- Mixing the game experience with the experience of meeting peoplePublication . Francisco, João; Jesus, RuiMeeting people face-to-face is a difficult task for many people. A mobile game can be the right "alibi" to help people to start a conversation. This paper describes the game "Knowing your Sympathy", which was developed with the purpose of knowing or making the first contact with people. The paper also presents the main questions of the study conducted during the evaluation of the game. The study was performed for 2 weeks by 13 participants living in the same or nearby neighborhoods.