Abstract
Image processing of particulate phases can provide an important assistance for the estimation of particle size and shape distributions in multiphase systems. The knowledge of these distributions is of major importance in the modeling of agitated liquid-liquid systems either for hydrodynamic and mass transfer (with or without chemical reaction) simulation. Often, obtaining these distributions implies visual/manual techniques for identifying, counting and measuring the particles. This implies high costs, intensive labor, weariness build-up and consequent high error rates. A largely automated computational approach presents a great potential for better performance. In this paper we describe our technique in image processing for shape discrimination and size classification for liquid drops in monochromatic digitized frames. We empirically evaluate our approach on examples of images.

Abstract
We study a mathematical model of immune response by T cells where the regulatory T cells (Treg) inhibit interleukin 2 secretion. The bystander proliferation to an immune response is modelled. We consider an asymmetry reflecting that the difference between the growth and death rates can be higher for the active T cells and Tregs than for the inactive. This asymmetry leads to a better understanding of the bystander proliferation. An exposure to a pathogen results in an increased proliferation rate of the bystander T cells. If the population of the bystander T cells becomes large enough, autoimmunity can arise, eventually after a long transient period.

Abstract
Clinical practice and research are facing a new challenge created by the rapid growth of health information science and technology, and the complexity and volume of biomedical data. Machine learning from medical data streams is a recent area of research that aims to provide better knowledge extraction and evidence-based clinical decision support in scenarios where data are produced as a continuous flow. This year's edition of AIME, the Conference on Artificial Intelligence in Medicine, enabled the sound discussion of this area of research, mainly by the inclusion of a dedicated workshop. This paper is an introduction to LEMEDS, the Learning from Medical Data Streams workshop, which highlights the contributed papers, the invited talk and expert panel discussion, as well as related papers accepted to the main conference.

Abstract
Como corolário do trabalho de investigação e desenvolvimento, iniciado em 1996, na área das tecnologias da comunicação e dos serviços multimédia em contexto de formação profissional, pretende-se, com este estudo, identificar os principais contributos das ciências e tecnologias da comunicação e da educação nos processos de especificação, concepção, desenvolvimento e utilização do sistema de gestão de aprendizagem Formare, em contexto de formação profissional. Tendo em conta a fundamentação teórica, a participação em projectos de investigação e de inovação e uma vivência prática de mais de 14 anos de actividade na área do ensino a distância, do eLearning e do bLearning em contexto empresarial, desenvolveu-se um modelo conceptual para a nova versão do LMS Formare baseada nos fundamentos da comunicação e da gestão da aprendizagem em ambiente real de utilização. Para além de estudar os fundamentos das Learning Organizations, do Ensino a Distância, da Comunicação Educacional Multimédia, do eLearning, do bLearning e dos seus principais componentes, esta tese focaliza-se na análise de dois estudos de caso, suportados pelo Formare – um, em contexto de Auto-aprendizagem no Campus PT, e outro, em contexto de Aprendizagem Colaborativa na Formação de eFormadores. Pela análise das conclusões de cada um dos estudos de caso realizados, foi possível validar as opções tecnológicas e pedagógicas utilizadas, conhecer a percepção, o grau de utilização e a avaliação pedagógica dos formandos, assim como identificar os principais indicadores de implementação do eLearning nas organizações que aderiram ao LMS Formare. A tese termina com a apresentação dos principais resultados, limitações e conclusões do estudo de investigação, e apresenta um conjunto de considerações futuras nesta área de actividade, esperando contribuir para o desenvolvimento do eLearning em contexto de uma Learning Organization.;This study has grown out of research and development work, begun in 1996, in the field of communication technologies and multimedia services in the context of professional training. It has been designed to identify and report on the factors that determine the way in which communication technologies influence the performance of learners in learning contexts and distributed learning communities and in eLearning and bLearning environments. It is based on the specification and validation experience that has been gained from solutions used in the “Formare” learning management system. A conceptual model for the new version of LMS Formare has been developed on the basis of a number of factors. These include a theoretical framework, research outcomes and the results of innovation projects allied with 14 years professional experience of delivering distance teaching, eLearning and bLearning in a business context, this delivery being based on the principles of communication and the management of learning in real learning environments. In addition to investigating the underlying principles and main components of learning organizations, distance teaching, communication, multimedia education, eLearning and bLearning, this thesis focuses on the analysis of two case studies supported by Formare. The first of these involves self-learning on Campus PT and the second collaborative learning in the context of training eTrainers. For each of the case studies, the technological and pedagogical options employed were analyzed and validated. Data was collected on trainee’s perceptions, degree of use and pedagogical assessments. The main conclusions and indicators involved in implementing eLearning in organizations using LMS Formare were also identified. The thesis draws these various threads together by presenting the main results, limitations and conclusions of the research. It also outlines a number of concerns bearing on future activity in this area, thus attempting to contribute to the development of eLearning in Learning Organizations.

Abstract
The wind power generation is experiencing a rapid growth, achieving the highest number of European installations in 2010 comparing to other renewable sources. The need for a smarter grid capable of integrating several decentralized sources of energy and the increasing need for energy in urban areas, has led to an increase interest in wind turbines for the urban areas. In these environments, vertical axis wind turbines (VAWT) have several advantages over horizontal axis wind turbines (HAWT), namely: their ability to operate closer to the ground; their insensitivity to yaw wind directions; the smaller number of components; the operation at low sound emissions; the ability to generate energy from wind in skew flow. One problem with the lift-type VAWT (Darrieus wind turbines) is their natural inability to self-start at low wind speeds without extra components. Hence, a new blade profile for Darrieus type VAWT is presented in this paper, capable to self-start at low wind speeds. A methodology is developed to compare the new blade profile with other known airfoils. Finally, conclusions are duly drawn.

Abstract
We consider the weight-constrained minimum spanning tree problem which has important applications in telecommunication networks design. We discuss and compare several formulations. In order to strengthen these formulations, new classes of valid inequalities are introduced. They adapt the well-known cover, extended cover and lifted cover inequalities. They incorporate information from the two subsets: the set of spanning trees and the knapsack set. We report computational experiments where the best performance of a standard optimization package was obtained when using a formulation based on the well-known Miller-Tucker-Zemlin variables combined with separation of cut-set inequalities.