Uma abordagem baseada em filtragem colaborativa integrada a mapas de saliência para a recomendação de imagens

Nowadays, the amount of customers using sites for shopping is greatly increasing, mainly due to the easiness and rapidity of this way of consumption. The sites, differently from physical stores, can make anything available to customers. In this context, Recommender Systems (RS) have become indispensable to help consumers to find products that may possibly pleasant or be useful to them. These systems often use techniques of Collaborating Filtering (CF), whose main underlying idea is that products are recommended to a given user based on purchase information and evaluations of past, by a group of users similar to the user who is requesting recommendation. One of the main challenges faced by such a technique is the need of the user to provide some information about her preferences on products in order to get further recommendations from the system. When there are items that do not have ratings or that possess quite few ratings available, the recommender system performs poorly. This problem is known as new item cold-start. In this paper, we propose to investigate in what extent information on visual attention can help to produce more accurate recommendation models. We present a new CF strategy, called IKB-MS, that uses visual attention to characterize images and alleviate the new item cold-start problem. In order to validate this strategy, we created a clothing image database and we use three algorithms well known for the extraction of visual attention these images. An extensive set of experiments shows that our approach is efficient and outperforms state-of-the-art CF RS.

Entre chegadas e partidas: a sociabilidade em trânsito

New ways of sociability can be perceive in a historical context marked by the social change. The investigation developed by this thesis follow this idea, pointing the emergency of social relations established between individuals in drift. The foremost aim of this research was to assay, using a case study, the bonds constructed among the people that attend the Terminal Central - Pratic Shopping of Uberlândia-MG, the main responsible for the reception and distribution of public transport of the city. With the growth of the urban centers, their population became attractive objects of analysis in the social science field and the understanding of the city, in their core, by the dwellers displacement. Thus, after the separation of the people that use the Terminal Central in seven groups (students, families and couples, elderly, deaf and/or mute, employees of the stores in Terminal and of the bus companies), their interactions tried to be understood, by identifying the similarity with the sociability in traffic studies. In places with a great flow of people, the sociability in traffic suggests bonds of friendship, kindness, as foray, impersonality, frailty and the sudden break of contact.