Pedro S. Ferreira

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The concept of value has a great relevance in the definition and implementation of a performance management system in the context of cooperate networked production organisations. These new forms of organizations are, in many cases, still lacking suitable performance measures. Based on this idea, this paper we will discuss the problem of performance(More)
This communication describes a virtual reality technology application in the construction-training domain. A prototype was developed that serves as a didactic tool for civil engineering students of disciplines concerned with building construction. Geometric modeling and virtual reality techniques are used on the visual simulation of construction processes(More)
Normally, academic applications of computer-aided design in construction provide a visual presentation of the final state of the project and they are not able to produce changes in the geometry following the construction process. It was developed a didactic prototype that allows physical changes in a building component. This prototype illustrates the(More)
To successfully compete in the market, European SMEs will have to adopt new business models and establish dynamic and non-hierarchical networks, assuring quick response, fast time to market, differentiated offerings and competitive prices. Sustainability will be found in high-variety and low-volume businesses, related with complex products design and(More)
The use of virtual reality techniques in the development of educational applications brings new perspectives to the teaching of subjects related to the field of civil construction. In order to obtain models, which would be able to visually simulate the construction process of two types of construction work, the research turned to the techniques of geometric(More)
In this work we explicit a derivative-free trust-region algorithm for unconstrained optimization based on the paper (Computational Optimization and Applications 53: 527–555, 2012) proposed by Powell. The objective function is approximated by quadratic models obtained by polynomial interpolation. The number of points of the interpolation set is fixed. In(More)
Performance management in collaborative networks requires approaches suitable to deal with a larger domain than in traditional organisations, including new processes, new stakeholders and a less clear border between internal and external. The proposed approach addresses objectives and strategies setting, performance measurement and evaluation, monitoring,(More)
Sabotaging behavior and decision-making during ontogeny in herbivorous insects remain largely underappreciated. Insects that use hosts bearing articulated laticifers would be expected to cut trenches to deactivate this plant defense. Contrary to this expectation, larvae of Danaus erippus display vein cutting when feeding on Asclepias curassavica, a host(More)
In this work we present an algorithm for solving constrained optimization problems that does not make explicit use of the objective function derivatives. The algorithm mixes an inexact restoration framework with filter techniques, where the forbidden regions can be given by the flat or slanting filter rule. Each iteration is decomposed in two independent(More)
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