Hand gesture recognition for human computer interaction : a comparative study of different image features

Hand gesture recognition for human computer interaction, being a natural way of human computer interaction, is an area of active research in computer vision and machine learning. This is an area with many different possible applications, giving users a simpler and more natural way to communicate with robots/systems interfaces, without the need for extra devices. So, the primary goal of gesture recognition research is to create systems, which can identify specific human gestures and use them to convey information or for device control. For that, vision-based hand gesture interfaces require fast and extremely robust hand detection, and gesture recognition in real time. In this study we try to identify hand features that, isolated, respond better in various situations in human-computer interaction. The extracted features are used to train a set of classifiers with the help of RapidMiner in order to find the best learner. A dataset with our own gesture vocabulary consisted of 10 gestures, recorded from 20 users was created for later processing. Experimental results show that the radial signature and the centroid distance are the features that when used separately obtain better results, with an accuracy of 91% and 90,1% respectively obtained with a Neural Network classifier. These to methods have also the advantage of being simple in terms of computational complexity, which make them good candidates for real-time hand gesture recognition.

Quantitative image analysis as a tool for Yarrowia lipolytica dimorphic growth evaluation in different culture media

Yarrowia lipolytica, a yeast strain with a huge biotechnological potential, capable to produce metabolites such as γ-decalactone, citric acid, intracellular lipids and enzymes, possesses the ability to change its morphology in response to environmental conditions. In the present study, a quantitative image analysis (QIA) procedure was developed for the identification and quantification of Y. lipolytica W29 and MTLY40-2P strains dimorphic growth, cultivated in batch cultures on hydrophilic (glucose and N-acetylglucosamine (GlcNAc) and hydrophobic (olive oil and castor oil) media. The morphological characterization of yeast cells by QIA techniques revealed that hydrophobic carbon sources, namely castor oil, should be preferred for both strains growth in the yeast single cell morphotype. On the other hand, hydrophilic sugars, namely glucose and GlcNAc caused a dimorphic transition growth towards the hyphae morphotype. Experiments for γ-decalactone production with MTLY40-2P strain in two distinct morphotypes (yeast single cells and hyphae cells) were also performed. The obtained results showed the adequacy of the proposed morphology monitoring tool in relation to each morphotype on the aroma production ability. The present work allowed establishing that QIA techniques can be a valuable tool for the identification of the best culture conditions for industrial processes implementation.

Enhancement of adhesion and promotion of osteogenic differentiation of human adipose stem cells by poled electroactive poly(vinylidene fluoride)

Poly(vinylidene fluoride) (PVDF) is a biocompatible material with excellent electroactive properties. Non-electroactive α-PVDF and electroactive β-PVDF were used to investigate the substrate polarization and polarity influence on the focal adhesion size and number as well as on human adipose stem cells (hASCs) differentiation. hASCs were cultured on different PVDF surfaces adsorbed with fibronectin and focal adhesion size and number, total adhesion area, cell size, cell aspect ratio and focal adhesion density were estimated using cells expressing EGFP-vinculin. Osteogenic differentiation was also determined using a quantitative alkaline phosphatase assay. The surface charge of the poled PVDF films (positive or negative) influenced the hydrophobicity of the samples, leading to variations in the conformation of adsorbed extracellular matrix (ECM) proteins, which ultimately modulated the stem cell adhesion on the films and induced their osteogenic differentiation.

A educação como empoderamento na ótica do desenvolvimento: uma discussão de modelos

Apresentamos nesta comunicação uma tese de ressignificação da educação como empoderamento tendo como foco uma agenda de desenvolvimento justo, digno e inclusivo, e equacionamos os seus principais tipos ou modelos, partindo do princípio que o empoderamento, pelo facto de remeter para diversas conotações ideológicas, não permite almejar consensos quando se trata de o tomar como sinal distintivo ou imagem de marca de uma educação cuja aposta principal é a promoção de um desenvolvimento humano verdadeiramente empenhado em corresponder às expectativas normativas das pessoas em termos de justiça, respeito, dignidade, liberdade e direitos fundamentais para todos.

School health promotion and teacher professional identity

PURPOSE – Health and education are inextricably linked. Health promotion sits somewhat uncomfortably within schools, often remaining a marginal aspect of teachers’ work. The purpose of this paper is to examine the compatibility of an HP-initiative with teacher professional identity. DESIGN/METHODOLOGY/APPROACH – A qualitative research design was adopted consisting of semi-structured interviews. In total, 49 teachers in two school districts in the Auvergne region in central France were interviewed in depth post having completed three years’ involvement in a health promoting schools initiative called “Learning to Live Better Together” (“Apprendre a Mieux Vivre Ensemble”). FINDINGS – Teachers in the study had a broad conceptualisation of their role in health promotion. In keeping with international trends, there was more success at classroom than at whole school level. While generally teachers can be reluctant to engage with health promotion, the teachers in this study identified having little difficulty in understanding their professional identity as health promoters and identified strong compatibility with the HP-initiative. PRACTICAL IMPLICATIONS – Teachers generally viewed professional development in health promotion in a positive light when its underlying values were commensurate with their own and when the context was seen as compatible with the school mission. The promotion of health in schools needs to be sensitive to professional identity and be tailored specifically to blend more successfully with current teacher identity and practice. ORIGINALITY/VALUE – The promotion of health in schools needs to be sensitive to professional identity and be tailored specifically to blend more successfully with current teacher identity and practice.

O evento levou... Comunicação de marca de uma cidade-sede

Tese de Doutoramento em Ciências da Comunicação - Especialidade em Comunicação Estratégica e Organizacional

Certificação ISO 9001 e Gestão de Recursos Humanos: precedentes e consequentes: estudo de caso das Unidades de Serviços Certificadas da Universidade do Minho

Dissertação de mestrado em Gestão de Recursos Humanos

Intervir através da educação física na coeducação: realidade ou intenção?

Intervir de forma consciente e organizada em prol da promoção da igualdade de oportunidades na escola tem sido, nas últimas décadas, um dos propósitos da Educação Física (EF) na Europa. Através das rotinas e das oportunidades que se proporcionam, rapazes e raparigas têm acesso a uma prática de atividade física e desportiva (AFD) que lhes possibilita aperfeiçoar capacidades, competências e atitudes. Consideramos que o contributo da EF na educação é de um valor significativo, viabilizando às crianças e jovens construir a sua imagem corporal e os estereótipos de género, desenvolver afectos e emoções, cultivar a sua relação com os outros, criar capacidades e valores, ajudando deste modo uma formação das atitudes individuais ou coletivas, que respeitem a igualdade de género e, por isso, os direitos humanos. Este estudo foi realizado a partir da informação recolhida, através da aplicação de um questionário, a uma amostra de 993 crianças, 57.5% raparigas e 42.5% rapazes, com idades compreendidas entre os 10 e 12 anos, pertencentes a várias escolas do ensino público e ambicionou comparar as perceções e preferências de rapazes e raparigas relativamente às práticas AFD que decorrem na disciplina de EF, para se poderem apresentar alternativas de práticas mais flexíveis e integradoras. A partir dos nossos resultados podemos concluir que a AFD na escola continua a ser muito marcada por práticas de técnicas de movimento, jogos e competições desportivas, vivências muito identificadas com os estereótipos masculinos e que, nem sempre ajudam à formação de um bom esquema corporal e de comportamentos que se tendem a manter ao longo da vida, para muita(o)s jovens. Sugerimos que as atividades oferecidas às crianças e jovens nas escolas sejam mais diversificadas e inclusivas, impondo um nível de desempenho e de satisfação mais adequado a cada caso em particular, devendo estar mais centradas quer em atividades de ar livre, quer em práticas que desenvolvem também as dimensões sensitiva, expressiva e corporal do(a)s aluno(a)s.

Contributos do postal ilustrado para a história do Free Card

Dissertação de mestrado em Ciências da Comunicação (área de especialização em Publicidade e Relações Públicas)