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Sistema de Avaliação suportado pelo WWW

This article presents a system, developed upon the World Wide Web, that allows formative/diagnostic and cumulative evaluation tasks for courses with a large number of students. Tests developed on this system are composed by multiple choice questions, with automatic correction and limited answering time. This system has the capability of self regulating the difficulty level of the q...

Pancreas-Kidney Transplantation: Analysis of 150 patients from one Centre in Po...

Introduction: Simultaneous pancreas-kidney transplantation (SPKT) outcomes are conditioned in the short-term mostly by post-operative complications. In the long-term, cardiovascular (CV) disease and immunological loss are the main limitations to transplant survival. Aims: To analyse retrospectively the results from 150 SPKT performed at our centre. Patients and Methods: The 81 females and 69 males had a mea...

Trousseau's Syndrome Due to Asymptomatic Pancreatic Adenocarcinoma

Os autores relatam um caso de Síndrome de Trousseau, manifestado por trombose venosa migratória e embolia pulmonar, num doente de 58 anos assintomático até à data de internamento. O estudo desencadeado revela adenocarcinoma do pâncreas com metástases hepáticas, e a situação torna-se ainda mais grave após a ocorrência de um acidente vascular cerebral isquémico, aparentemente em relação com a paragem por 24 horas...

Corrosion behaviour of titanium in the presence of Streptococcus mutans

Objective The main aim of this in vitro study was to evaluate the influence of Streptococcus mutans on the corrosion of titanium. Methods S. mutans biofilms were formed on commercially pure titanium (CP-Ti) square samples (10 mm × 10 mm × 1 mm) using a culture medium enriched with sucrose. Open circuit potential (OCP) and electrochemical impedance spectroscopy (EIS) measurements were used to evaluate the cor...

Hooke and Jeeves based multilevel coordinate search to globally solving nonsmoo...

Publicado em "AIP Conference Proceedings", vol. 1558 ; In this paper, we present a derivative-free multilevel coordinate search (MCS) approach, that relies on the Hooke and Jeeves local search, for globally solving bound constrained optimization problems. Numerical experiments show that the proposed algorithm is effective in solving benchmark problems, when compared with the well-known solvers MCS and DIRECT.

Multistart Hooke and Jeeves filter method for mixed variable optimization

AIP Conference Proceedings, vol. 1558 ; In this study, we propose an extended version of the Hooke and Jeeves algorithm that uses a simple heuristic to handle integer and/or binary variables and a filter set methodology to handle constraints. This proposal is integrated into a multistart method as a local solver and it is repeatedly called in order to compute different optimal solutions. Then, the best of all ...

An artificial fish swarm algorithm based hyperbolic augmented Lagrangian method

Documento submetido para revisão pelo pares a publicar em Journal of computational and applied mathematics. ISSN 0377-0427. Versão "In Press, Corrected Proof" disponível em http://www.sciencedirect.com/science/article/pii/S0377042713004226 ; This paper aims to present a hyperbolic augmented Lagrangian (HAL) framework with guaranteed convergence to an ϵ-global minimizer of a constrained nonlinear optimization p...

Multistart hooke and jeeves filter method for mixed variable optimization

In this study, we propose an extended version of the Hooke and Jeeves algorithm that uses a simple heuristic to handle integer and/or binary variables and a filter set methodology to handle constraints. This proposal is integrated into a multistart method as a local solver and it is repeatedly called in order to compute different optimal solutions. Then, the best of all stored optimal solutions is selected as t...

Characterizations of global reachability of 2D structured systems

Reconstructibility of time-invariant and periodic behavioral systems