Detection and thinning of edges in previously known directions

This work presents a study on the generation of digital masks aiming at edge detection with previously known directions. This solution is important when edge direction is available either from a direction histogram or from a prediction based on camera and object models. A modification in the non-maximum suppression method of thinning is also presented enabling the comparison of local maxima for any edge directions. Results with a synthetic image and with crops of a CBERS satellite images are presented showing an example with its application in road detection, provided that directions are previously known.

Body and Didactics. Possible directions of international research

The paper investigates the role of the body in didactics. It looks up for points of contact between the functional sceneries of the classroom and some recent approaches, such like simplexity, neurosciences and enactivism. The two experiments presented they aim to demonstrate the importance of body awareness to improve the didactic quality. The first experience used a SenseWear Armband that provided data about the energetic expenditure of a teacher during diff erent activities in a lesson. Th e second experiment relied on a neurofeedback device integrated to a sensor, it detected body temperature with the aim of understanding the role of the body in the process of self-regulation-learning and management of attention and arousal.

Trends in Brazilian academic production in the History of Mathematics Education: directions from EBRAPEM

The number of papers on History of Mathematics Education presented at EBRAPEM (Brazilian Meeting of Graduate Students in Mathematics Education) has increased significantly between 2003 and 2008. This article presents a study with the aim of identifying themes, periods in focus, and sources and theoretical and methodological references used by the authors of the papers on History of Mathematics Education published in the proceedings of VII, VIII, IX, X, XI and XII EBRAPEM. The study indicates that the approach of ongoing research in History of Mathematics Education in Brazil has been similar to the approach of research in History of Education in general. However, the institutional separation between these two areas of investigation is noted as a factor rendering communication between both groups of researchers difficult.

Visual conditions and postural directions affect postural sway variability in patients with Parkinson’s disease

Postural sway variability was evaluated in Parkinson’s disease (PD) patients at different stages of disease. Twenty PD patients were grouped into two groups (unilateral, 14; bilateral, 6) according to disease severity. The results showed no significant differences in postural sway variability between the groups (p ≥ 0.05). Postural sway variability was higher in the antero-posterior direction and with the eyes closed. Significant differences between the unilateral and bilateral groups were observed in clinical tests (UPDRS, Berg Balance Scale, and retropulsion test; p ≤ 0.05, all). Postural sway variability was unaffected by disease severity, indicating that neurological mechanisms for postural control still function at advanced stages of disease. Postural sway instability appears to occur in the antero-posterior direction to compensate for the stooped posture. The eyes-closed condition during upright stance appears to be challenging for PD patients because of the associated sensory integration deficit. Finally, objective measures such as postural sway variability may be more reliable than clinical tests to evaluate changes in balance control in PD patients.

A matheuristic for the selection of beam directions and dose distribution in radiotherapy planning

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)