Enhancing the selection of a model-based clustering with external categorical variables

In cluster analysis, it can be useful to interpret the partition built from the data in the light of external categorical variables which are not directly involved to cluster the data. An approach is proposed in the model-based clustering context to select a number of clusters which both fits the data well and takes advantage of the potential illustrative ability of the external variables. This approach makes use of the integrated joint likelihood of the data and the partitions at hand, namely the model-based partition and the partitions associated to the external variables. It is noteworthy that each mixture model is fitted by the maximum likelihood methodology to the data, excluding the external variables which are used to select a relevant mixture model only. Numerical experiments illustrate the promising behaviour of the derived criterion.

Prognostic modelling of breast cancer patients: a benchmark of predictive models with external validation

Dissertação apresentada para obtenção do Grau de Doutor em Engenharia Electrotécnica e de Computadores – Sistemas Digitais e Percepcionais pela Universidade Nova de Lisboa, Faculdade de Ciências e Tecnologia

Balanced Scorecard

Mestrado Em Engenharia Mecânica - Ramo Gestão Industrial

Resource Scheduling in Residential Microgrids Considering Energy Selling to External Players

The operation of distribution networks has been facing changes with the implementation of smart grids and microgrids, and the increasing use of distributed generation. The specific case of distribution networks that accommodate residential buildings, small commerce, and distributed generation as the case of storage and PV generation lead to the concept of microgrids, in the cases that the network is able to operate in islanding mode. The microgrid operator in this context is able to manage the consumption and generation resources, also including demand response programs, obtaining profits from selling electricity to the main network. The present paper proposes a methodology for the energy resource scheduling considering power flow issues and the energy buying and selling from/to the main network in each bus of the microgrid. The case study uses a real distribution network with 25 bus, residential and commercial consumers, PV generation, and storage.

Shoulder Kinematics Is Not Influenced by External Load During Elevation in the Scapular Plane

The current study aimed to compare the shoulder kinematics (3D scapular orientation, scapular angular displacement and scapulohumeral rhythm) of asymptomatic participants under unloaded and loaded conditions during unilateral shoulder elevation in the scapular plane. We used a repeated-measures design with a convenience sample. Eleven male participants with an age range of 21–28 years with no recent history of shoulder injury participated in the study. The participants performed isometric shoulder elevation from a neutral position to approximately 150 degrees of elevation in the scapular plane in intervals of approximately 30 degrees during unloaded and loaded conditions. Shoulder kinematic data were obtained with videogrammetry. During shoulder elevation, the scapula rotated upwardly and externally, and tilted posteriorly. The addition of an external load did not affect 3D scapular orientation, scapular angular displacement, or scapulohumeral rhythm throughout shoulder elevation (P > .05). In clinical practice, clinicians should expect to observe upward and external rotation and posterior tilt of the scapula during their assessments of shoulder elevation. Such behavior was not influenced by an external load normalized to 5% of body weight when performed in an asymptomatic population.

The adoption of cloud computing by SMEs: identifying and coping with external factors.

Comunicação apresentada na CAPSI 2011 - 11ª Conferência da Associação Portuguesa de Sistemas de Informação – A Gestão de Informação na era da Cloud Computing, Lisboa, ISEG/IUL-ISCTE/, 19 a 21 de Outubro de 2011.

RoutesMobilityModel: easy realistic mobility simulation using external information services

Workshop on ns-3 (WNS '15). 13, May, 2015. Castelldefels, Spain.

Strength improvement of adhesively-bonded scarf repairs in aluminium structures with external reinforcements

Adhesively bonded techniques are an attractive option to repair aluminium structures, compared to more traditional methods. Actually, as a result of the improvement in the mechanical characteristics of adhesives, adhesive bonding has progressively replaced the traditional joining methods. There are several bonded repair configurations, as single-strap, double-strap and scarf. Compared with strap repairs, scarf repairs have the advantages of a higher efficiency and the absence of aerodynamic disturbance. The higher efficiency is caused by the elimination of the significant joint eccentricities of strap repairs. Moreover, stress distributions along the bond length are more uniform, due to tapering of the scarf edges. The main disadvantages of this technique are the difficult machining of the surfaces, associated costs and requirement of specialised labour. This work reports on an experimental and numerical study of the tensile behaviour of two-dimensional (2D) scarf repairs of aluminium structures bonded with the ductile epoxy adhesive Araldite® 2015. The numerical analysis, by Finite Elements (FE), was performed in Abaqus® and used cohesive zone models (CZM) for the simulation of damage onset and growth in the adhesive layer, thus enabling the strength prediction of the repairs. A parametric study was performed on the scarf angle (α) and different configurations of external reinforcement (applied on one or two sides of the repair, and also different reinforcement lengths). The obtained results allowed the establishment of design guidelines for repairing, showing that the use of external reinforcements enables increasing α for equal strength recovery, which makes the repair procedure easier. The numerical technique was accurate in predicting the repairs’ strength, enabling its use for design and optimisation purposes.

Contributos para a elaboração de um manual de procedimentos de compras públicas

A área de compras públicas tem vindo a assumir um papel preponderante na gestão estratégica das instituições públicas. Decorrente da publicação do Código dos Contratos Públicos, e na sequência das sucessivas alterações legislativas, quer nacionais, quer comunitárias, as instituições devem ter um Manual de Procedimentos que compreenda a multiplicidade de aspetos relacionados com a área de compras. O presente projeto tem como objetivo de estudo contribuir para a elaboração de um Manual de Procedimentos na área das Compras Públicas. O objetivo último será, por um lado, permitir ao auditor, no âmbito de uma auditoria à área de compras, formar uma opinião e emitir um parecer sobre a matéria analisada, e por outro lado, contribuir para aperfeiçoar os Sistemas de Controlo Interno dessas Instituições. Pela revisão da literatura, fomos conduzidos a abordar o contexto regulamentar da área de compras em Portugal, a analisar a perspetiva estratégica desta área, passando por uma descrição das diversas fases que compõem o processo de compras públicas, considerando ainda, uma abordagem ao sistema de controlo interno e riscos de negócio. Por fim, foi efetuada uma análise sobre a perspetiva de auditoria, na qual os auditores, quer internos, quer externos, têm um papel fundamental na promoção de melhorias na contratação pública, particularmente na adoção de uma abordagem construtiva e realçando as boas práticas. Decorrente da revisão da literatura, aferimos as perguntas de investigação e aplicamos a metodologia de um estudo de caso único numa instituição de ensino superior, através da elaboração de entrevistas e observação direta e participativa do investigador. As conclusões finais revelaram que o modelo de análise utilizado no nosso estudo tem no universo dos Serviços da Presidência do Instituto Politécnico do Porto uma taxa de confirmação de 59%, realçando-se positivamente o resultado da componente relativa à operacionalização das compras públicas, e destacando-se, de forma menos significativa, a componente relativa à política e gestão estratégica.

Studying the impact of co-authorship with external researchers:the case of research community in Portugal using social network analysis.

Project work presented as a partial requirement to obtain a Master Degree in Information Management

Different in Vivo Reactivity Profile in Health Care Workers and Patients with Spina Bifida to Internal and External Latex Glove Surface-Derived Allergen Extracts

BACKGROUND: Allergy to natural rubber latex is a well-recognized health problem, especially among health care workers and patients with spina bifida. Despite latex sensitization being acquired in health institutions in both health care workers and patients with spina bifida, differences in allergen sensitization profiles have been described between these two risk groups. OBJECTIVE: To investigate the in vivo reactivity of health care workers and patients with spina bifida to extracts of internal and external surfaces of latex gloves and also to specific extracts enriched in major allergens for these risk groups. METHODS: Gloves from different manufacturers were used for protein extraction, and salt precipitation and hydrophobic interaction chromatography (HIC) were applied to obtain the enriched latex extracts. The major latex allergens were quantified by an enzyme immunoassay. The extracts obtained were tested in 14 volunteers using skin prick tests (SPT). RESULTS: Latex glove extracts enriched in the hydrophobic allergens that are most often seen in patients with spina bifida were obtained by selective precipitation, whereas HIC produced extracts enriched in the hydrophilic allergens commonly found in health care workers. The health care workers had positive SPTs to glove extracts from internal surfaces and to the hydrophilic allergen-enriched extracts. By contrast, patients with spina bifida had larger skin reactions both to external glove extracts and to the extracts enriched with the hydrophobic major allergens for this risk group. Despite the protein concentration of these extracts being less than half the concentration of the commercial extract, the weal-and-flare reactions were of similar magnitude. CONCLUSION: Using novel latex extracts, our study showed a different in vivo reactivity pattern in health care workers and in patients with spina bifida to extracts of the internal and external surfaces of gloves, which suggests that sensitization may occur by different routes of exposure, and that this influences the allergen reactivity profiles of these risk groups

Determinants of Portuguese external imbalances

A Work Project, presented as part of the requirements for the Award of a Masters Degree in Economics from the NOVA – School of Business and Economics

Essay on external imbalances within the Euro Area

A Work Project, presented as part of the requirements for the Award of a Masters Degree in Economics from the NOVA – School of Business and Economics

External brand extensions impact on Diesel's brand image

A Work Project, presented as part of the requirements for the Award of a Masters Degree in Management from the NOVA – School of Business and Economics