Abstract
Bad posture while working or playing videogames can affect our life quality and impose negative economic consequences over time. There's raising concern in companies regarding worker's wellness, many adopting preventive measures. Specialized training in posture is important to prevent occupational activities risks and to foster health promotion. In this paper, we present a study of different classifiers to detect good and bad body postures in workplaces. A set classifiers, namely artificial neural networks, support vector machine, decision trees, discriminant analysis, logistic regression, treebagger and naïve Bayes, were tested in three-dimensional acquisitions of 100 people for automatic determination of the type of body posture. The best classifier was the treebagger with a rating of True Positive and True Negative of 93.3% and 96.2%, respectively.

Abstract
According to the World Health Organization, 85% of the world population suffers from back pain, which accounts for over 50% of physical incapacity, permanent or temporary, among individuals in working-age. In most situations, this is caused by an incorrect posture, which causes changes in the spine structure. This paper proposes an instrumented vest for postural reeducation to address this issue. The vest has a set of inertial measurement unit (IMU) sensors strategically placed to provide an accurate characterization of the spine profile. The sensor readings are classified by a central processing unit. In case of an incorrect posture, users are alerted by an audio signal and through vibration. The wearable system works in stand-alone mode, but can also communicate with external systems through an API. Two applications were developed to communicate with the device through this API, one intended to run on a desktop computer and the other one for Android devices. These applications monitor spine profiles in real time and notify the user of incorrect postures, among other functionalities. The device prototype and the applications have been tested by 10 individuals in two different settings, first without any kind of feedback and then with feedback enabled. The tests demonstrate the usability, accuracy and robustness of the system, proving its high level of reliability in classifying postures and effectiveness for postural reeducation. In the future, the system is expected to be used as a platform for a serious game, to promote posture reeducation in a real world scenario.

Abstract
Telerehabilitation is an alternative way for physical therapy of stroke patients. The monitoring and correction of exercises can be done through the analysis of body movements recorded by an optical motion capture system. This paper presents a first study to assess the use of Microsoft Kinect in the monitoring and rehabilitation of patients who have suffered a stroke. A comparative study was carried out to assess the accuracy of joint angle measurement with the Microsoft Kinect (for Windows and for Xbox One) and Optitrack (TM). The results obtained in the first experiment showed a good agreement in the measurements between the three systems, in almost all movements. These results suggest that Microsoft Kinect, a low cost and markerless motion capture system, can be considered as an alternative to complex and high cost motion capture devices for the monitoring and rehabilitation of stroke patients.

Abstract
The visual impaired are a specific minority group that can benefit from specific assistive systems in order to mitigate their mobility and accessibility constrains. In the last decade, our research group has been integrating and developing assistive technologies, focused in human-computer interaction, artificial vision, assisted navigation, pervasive computing, among others. Several projects and prototypes have been developed with the main objective of improving the blind's autonomy, mobility, and quality of life. Currently the technology has reached a maturation point that allows the development of systems based on video capturing, image recognition and location referencing, which are key for providing features of artificial vision, assisted navigation and spatial perception. The miniaturization of electronics can be used to create devices such as electronic canes that equipped with sensors can provide so much more contextual information to a blind user. The adoption of these systems is dependent of an information catalogue regarding points of interest and their physical location reference. In this paper we describe the current work on assistive systems for the blind and propose a new perspective on using the base information of those systems to provide new services to the general public. By bridging the gap between the two groups, we expect to further advance the development of the current systems and contribute to their economic sustainability.

Abstract
Digital systems and solutions providing location based services for everyday activities are supported by geographic information systems that are typically problem-oriented. Although recently some approaches try to combine data from multiple sources to provide a better user experience, most often than not, these extra sources of input are not meaningful and act merely as an extension or augmentation of the user’s physical context, providing extra data that not always adds extra value to the service. In this work, a geographic information system that provides valuable data for multiple audiences, with different restrictions and requirements, is presented. This work also presents the concept of ‘awareness’, implemented using a hierarchical layering system. Using lists of information layers, together with an appropriate categorization of user requirements, the proposed information system can feed different final applications with different data, for different types of users, promoting accessibility and universal access.

Abstract
Aging is a process inherent to the human condition and part of the human being’s life cycle, which can be degraded by the reduction in the individual’s physical and social activity. This problem can be augmented by the context in which the person is aging, e.g., family, health and social bonds. The elderly individuals’ well-being is related to the strength of their social bonds with their family and friends group, which can be difficult to maintain in some stages of the aging process. A, recently- proposed solution is the adoption of autonomous systems capable of autonomous interactions with the elderly. Such systems are designed to be able to interpret the individual’s state of mind and the current context in order to conduct an effective interaction with the elderly person. This study focuses on the interaction design between the autonomous system and the human person, by considering the elderly individual’s context and pursuing the type of interaction that will positively influence the reinforcement or maintenance of the person’s social bonds with the family and friends groups. The study was carried out by interviewing a group of elderly people, currently living in nursing homes and with limited access to their family and friends.