En este artículo se presenta la evaluación de la eficiencia de las búsquedas sobre una federación de repositorios de objetos de aprendizaje, en particular la Federação de Repositórios Educa Brasil - FEB, respecto a la velocidad de respuesta y cantidad de registros recuperados. El objetivo es determinar las bondades de esta arquitectura en las búsquedas centralizadas sobre recursos distribuidos, pensando en un futuro cercano en realizar una implementación similar para Colombia. Tal evaluación se llevó a cabo mediante un experimento, usando 10 términos de búsqueda del campo de la salud, y se hizo una comparación entre FEB y dos repositorios reconocidos: MERLOT y The Gateway. Para no tener sesgos respecto a los momentos y orígenes de las búsquedas, estas se realizaron 30 veces, cada una desde 3 ubicaciones diferentes: Brasil, Colombia y España. Los resultados obtenidos demostraron un menor tiempo promedio de respuesta estadísticamente significante comparado con MERLOT (valor P < 0,001), pero mayor comparado con The Gateway (valor P < 0,001). Finalmente, se evidenció un crecimiento constante de la cantidad de objetos de aprendizaje registrados en FEB durante los últimos dos años.

In this paper, it is presented the assessment of the searching performance over a federation of learning objects repositories, in particular the Federação de Repositórios Educa Brasil - FEB, with regard to the response speed and quantity of retrieved records. The aim is to determine the benefits of this structure in the centralized searches over distributed resources, thinking in a near future to build a similar implementation for Colombia. Such an evaluation was done throughout an experiment with 10 search terms in the health field and a comparison was made between FEB and two well-known repositories: MERLOT and The Gateway. In order to avoid biases regarding the searching times and locations, such searches were done 30 times from 3 different locations each: Brazil, Colombia and Spain. The results obtained showed a lower mean response time which was statistically significant compared to MERLOT (P value < 0,001), but a larger time compared to The Gateway (P value < 0,001). Finally, a continuous grow was evident in the amount of learning objects registered in FEB during the last two years.

The goal of this paper is to describe a system-aided performance and composition tool that aims to expand guitarist capacities by providing innovative ways in which the user can interact with the system. In order to achieve that, we decided to use an agent-based approach, independently modeling the active elements involved in a guitar performance as autonomous agents - named Left-Hand, Right-Hand, and Speaker (the guitar itself). These agents are able to communicate to each other in order to make some musical decisions, specially related to the chord's shape choice. The musical elements (harmony and rhythm) are independently defined respectively by the Left-Hand and Right-Hand agents. The most relevant aspects of this work, however, are the algorithms and strategies to process both harmonic and rhythmic data. Finally, we perform an evaluation of the system and discuss the results of the implemented techniques.