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- A practical approach to model banking risks using Loss Distribution Approach (LDA) in Basel II frameworkPublication . Barreira, Raquel; Pryer, Tristan; Tang, QiIn Basel II Capital Accord, the Advanced Measurement Approaches (AMA) is stated as one of the pillar stone methods for calculating corporate risk reserves. One of the common yet cumbersome methods is the one known as loss distribution approach (cf. [3]). In this article, we present an easy to implement scheme through electronic means and discuss some of the mathematical problems we encountered in the process together with proposed solution methods and further sought on the issues.
- The surface finite element method for pattern formation on evolving biological surfacesPublication . Barreira, Raquel; Elliott, C. M.; Madzvamuse, AnotidaIn this article we propose models and a numerical method for patternformation on evolving curved surfaces. We formulate reaction-diffusion equations onevolving surfaces using the material transport formula, surface gradients and diffusiveconservation laws. The evolution of the surface is defined by a material surface veloc-ity. The numerical method is based on the evolving surface finite element method. Thekey idea is based on the approximation of by a triangulated surface hconsistingof a union of triangles with vertices on . A finite element space of functions is thendefined by taking the continuous functions on hwhich are linear affine on each sim-plex of the polygonal surface. To demonstrate the capability, flexibility, versatility andgenerality of our methodology we present results for uniform isotropic growth as wellas anisotropic growth of the evolution surfaces and growth coupled to the solutionof the reaction-diffusion system. The surface finite element method provides a robustnumerical method for solving partial differential systems on continuously evolvingdomains and surfaces with numerous applications in developmental biology, tumourgrowth and cell movement and deformation.
- Keeping them involved: encouraging and monitoring student activityPublication . Williams, Bill; Neto, Pedro; Carvalho, IsabelIn the teaching of engineering, lecture classes are often essentially expository with students in a passive role, not preparing learners for autonomous work and this may contribute to high failure and attrition rates. One way to combat this is through the application of Active Learning (AL) methodologies. In this paper results are presented from the application of an AL Methodology in the classroom and outside it for a last year subject of a BEng degree. A Learner Activity Monitoring Matrix has been used to monitoring in-class learner activity. Also described is the implementation of AL outside class using an online learner management system (LMS) which permits voting by students on the quality of solutions proposed by their peers to resolve engineering problems posed by the lecturer. Empirical data regarding the online participation in the process of each learner is provided. A pre-post survey to reveal student perceptions regarding these methodologies is also presented.
- ITs in engineering education: joining efforts between SPEE and IGIPPublication . Williams, Bill; Neto, Pedro; Cardoso, Alberto; Carvalho, Carlos Vaz de; Magalhães, Fernão de; Rasteiro, M. Graça; Restivo, Maria Teresa; Zutin, Danilo G.The International Society for Engineering Education (IGIP) and The Portuguese Society for Engineering Education (SPEE), the first being the oldest European Society for Engineering Education in Europe and the second the very young Society for Engineering Education in Portugal, have been intensifying the collaboration between the two societies as well as the exchange and dissemination of information about their relevant activities, whilst promoting understanding and cooperation between their respective members. One possible way is to create joint working groups, open to the members of both societies, on common topics of interest. In fact, both societies already kicked off this activity. The first initiative happened during the 1st World Engineering Education Flash Week (WEE), Lisbon, 2011. The SPEE-IGIP Flash Moment was a one day event integrated in the main Conference, which was dedicated to “Information & Communication Technologies in Engineering Education”. ITs allow the development of different teaching strategies which contribute to enhance the learning outcomes of students. ITs are also particularly suited to develop Life Long Learning tools, in a broad range of Engineering subjects, either open to the general market or oriented to a very specific public. Examples of teaching strategies involving ITs have been addressed during the Flash Moment SPEE-IGIP which took place during WEE, and some are described in detail in the present work.
- Tracking engineering education research and development: contributions from bibliometric analysisPublication . Williams, Bill; Neto, PedroIn recent years, bibliometric analysis of publications has been receiving growing attention in engineering education research as an approach that can bring a number of benefits. In this paper two such forms, taxonomical analysis and citation analysis, are applied to papers from the first 2011 number of IEEE Transactions on Education (21 papers) and from the two 2011 numbers of the ASEE-published Advances in Engineering Education (22 papers). In the former approach, seven taxonomical dimensions are used to characterize the papers and in the second the references cited in the 43 papers were studied so as to analyze how the researchers were informed by previous studies. The results suggest that the silo effect identified by Wankat for disciplinary engineering education journals in 2009 was still apparent in the IEEE Transactions on Education in 2011. The Advances in Engineering Education papers show a wide range of cited references, including reference disciplines outside of engineering education, and this suggests that research published there is likely to be informed by a broad range of previous studies which may be interpreted as a sign of a growing maturity of engineering education as a research discipline.
- Investigação em educação em engenharia: um campo emergentePublication . Williams, Bill; Hattum-Janssen, Natascha van; Oliveira, José ManuelNum mundo cada vez mais globalizado e em que o rápido desenvolvimento científico e tecnológico ocupa um papel central no desenvolvimento das sociedades, torna-se cada vez mais relevante discutir o perfil desejável dos profissionais de engenharia capazes de dar resposta a estes desafios, e consequentemente, discutir as processos de formação desses futuros engenheiros. No contexto internacional, estas necessidades têm vindo a fazer emergir a Investigação em Ensino de Engenharia (IEE) como um campo de investigação autónomo. Norteando-se pelos critérios de identidade para um campo de investigação de Fensham (2004), usado também por Borrego (2007), como princípios orientadores de análise, este artigo pretende discutir a identidade do campo de IEE, caraterizar o seu estado atual no contexto internacional e no contexto Português e posicioná-lo relativamente às Ciências de Educação. Os autores visam igualmente identificar os desafios emergentes no crescimento e amadurecimento deste campo de investigação específico, de forma a que possa granjear reconhecimento quer nas Ciências da Educação, quer nas Engenharias, no contexto Português.
- On the Optimal Control of a Class of Non-Newtonian FluidsPublication . Guerra, Telma; Tiago, Jorge; Sequeira, AdéliaWe consider optimal control problems of systems governed by sta-tionary, incompressible generalized Navier-Stokes equations with shear depen-dent viscosity in a two-dimensional or three-dimensional domain. We study ageneral class of viscosity functions including shear-thinning and shear-thickeningbehavior. We prove an existence result for such class of optimal control prob-lems.
- Exhibiting cross-diffusion-induced patterns for reaction-diffusionsystems on evolving domains and surfacesPublication . Madzvamuse, Anotida; Barreira, RaquelThe aim of this manuscript is to present for the first time the application of the finite element method for solvingreaction-diffusion systems with cross-diffusion on continuously evolving domains and surfaces. Furthermore wepresent pattern formation generated by the reaction-diffusion system with cross-diffusion on evolving domains andsurfaces. A two-component reaction-diffusion system with linear cross-diffusion in bothuandvis presented. Thefinite element method is based on the approximation of the domain or surface by a triangulated domain or surfaceconsisting of a union of triangles. For surfaces, the vertices of the triangulation lie on the continuous surface. Afinite element space of functions is then defined by taking the continuous functions which are linear affine on eachsimplex of the triangulated domain or surface. To demonstrate the role of cross-diffusion to the theory of patternformation, we compute patterns with model kinetic parameter values that belong only to the cross-diffusionparameter space; these do not belong to the standard parameter space for classical reaction-diffusion systems.Numerical results exhibited show the robustness, flexibility, versatility, and generality of our methodology; themethodology can deal with complicated evolution laws of the domain and surface, and these include uniformisotropic and anisotropic growth profiles as well as those profiles driven by chemical concentrations residing inthe domain or on the surface
- Aplicação de problemas de controlo a uma estenose idealizadaPublication . Guerra, Telma; Tiago, JorgeNeste trabalho apresentamos, de forma sucinta, simulações numé-ricas de fluidos, de problemas do tipo Assimilação de Dados numa aborda-gem variacional. Apresentamos resultados aplicados à Hemodinâmica consi-derando uma geometria tridimensional na forma de uma estenose idealizadae recuperamos o perfil da velocidade do sangue nesta geometria.