Thesis

Computer Assisted Language Learning (CALL) systems aim to teach a language providing technology and motivation to the user. They allow us to implement pedagogical content, motivational techniques and corrective feedback. On this basis, we present Medieval Adventure, which is a CALL system that aims to teach Portuguese's basic levels to adults. Medieval Adventure teaches a second language mainly through pragmatic. The teachers may maintain their teaching methods, once we allow them to develop new content, namely tasks, conversations, interactions and scenarios. We allow teachers to take advantage of pedagogy, motivation techniques and corrective feedback. The user learns Portuguese performing the tasks, which involve exploring Medieval Adventure's world, namely interacting with characters and objects. Medieval Adventure has the adequate expressiveness for pedagogical content development, according to teachers, and it was well accepted by the users, as we concluded on the user tests.

Agriculture is indispensable for humankind survival, however mankind is leaving the countryside towards urbanized areas, abandoning that most important activity. This thesis describes the serious game developed to portrait the agricultural scenery of Castro Verde region, teaching about the difficulties faced by the local farmers, how agriculture affects the steppe birds, and how the birds influence the local tourism. The game was also designed to be entertaining in order to be played, otherwise players would get bored and avoid playing it, making it impossible to transmit the knowledge to them. Conclusions of the evaluation of this game showed that it was efficient in teaching about the agriculture impact on the steppe birds, and the difficulties the farmers face in order to get profit from their lands. Gamers have also found the game interesting despite it being an unfinished work which can be improved, by making it more appealing and fun.

Escherichia Coli is a Gram-negative, rod-shaped bacterium, and one of the oldest microorganisms that maintains a symbiotic relation with Men. It is very commonly used in research and, therefore, it has been long-time established as a reference in microbiology studies. In this work, the results of a multi-agents simulation of E-coli, using the Dynamic Energy Budget theory, are presented, with the goal of reproducing the life cycle behaviors and movement patterns that characterize this bacterium. The work also includes an implementation of a set of mutations based on the alteration of simulation variables and DEB parameters. The ION Framework was used as a development tool in order to generate the bacterial environment and the corresponding interaction protocols with the agents. The aim of this implementation is to test the possibility of using the DEB theory applied in a multi-agent scenario to obtain realistic results comparable with previously reported experimental investigation.

Gaze is a crucial method to communicate through non verbal signals. Due to our social nature, users usually expect to interact with synthetic characters just like they interact with other people. In our work, we are concerned about the authenticity and believability of synthetic characters during this reciprocal sequence of actions. Multiparty conversations are many times underestimated in synthetic character's field. Our work focuses on gaze as a multi-user communication tool. We present a solution, based on psychology theories of attention where multiple users interact with a synthetic character without breaking the suspension of belief. The work presented in this dissertation is located in this area of relevance and addresses the specific question of creating autonomous believable behaviour to support the engineering of believable synthetic characters. This dissertation specifically covers an eye gaze system based in anticipatory mechanisms, towards different users. The anticipatory behaviour proposed depends on each user's internal model, on the task progress, and it is inspired by psychology theories of visual attention, such as the spotlight model, covert and overt attention, and bottom-up and top-down processing. We believe that one synthetic character that is able to distinguish users and reacts differently towards them is rather believable that one that does not. In this dissertation, we show how supporting multiple users can be used to control the behaviour of a synthetic character interacting with different human users, and autonomously produce believable and understandable behaviour.