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Publications

2017

Mitigation in the Very Short-term of Risk from Wind Ramps with Unforeseen Severity

Authors
Pinto, M; Miranda, V; Saavedra, O; Carvalho, L; Sumaili, J;

Publication
JOURNAL OF CONTROL AUTOMATION AND ELECTRICAL SYSTEMS

Abstract
This paper addresses a critical analysis of the impact of the wind ramp events with unforeseen magnitude in power systems at the very short term, modeling the response of the operational reserve against this type of phenomenon. A multi-objective approach is adopted, and the properties of the Pareto-optimal fronts are analyzed in cost versus risk, represented by a worst scenario of load curtailment. To complete this critical analysis, a study about the usage of the reserve in the event of wind power ramps is performed. A case study is used to compare the numerical results of the models based on stochastic programming and models that take a risk analysis view in the system with high level of wind power. Wind power uncertainty is represented by scenarios qualified by probabilities. The results show that the reliability reserve may not be adequate to accommodate unforeseen wind ramps and therefore the system may be at risk.

2017

VirtualSign Game Evaluation

Authors
Escudeiro, P; Escudeiro, N; Norberto, M; Lopes, J;

Publication
SERIOUS GAMES, INTERACTION AND SIMULATION

Abstract
This paper presents the evaluation methods and techniques applied to the serious game developed within the VirtualSign project as well as the results achieved through those methods. VirtualSign is a Portuguese sign language bi-directional translator with three main components. The components are a gesture to text translator, a text to gesture translator and a serious game. The serious game aims to make the process of learning sign language easier and enjoyable using the VirtualSign bi-directional translator. The method used to evaluate the VirtualSign was the Quantitative Evaluation Framework (QEF). The translator undertakes a rigid validation process by both sign language experts and the deaf community. The evaluation process was also supported by questionnaires. The precision of the translator has a direct impact on the game performance. To evaluate the precision of the automatic translator we have used QEF and 10-fold cross validation to estimate the accuracy of the translator. The experimental results show a precision above 90%. In the identification of the Portuguese Sign Language terms As for the game the quality rate is 88% based on the QEF evaluation.

2017

Evaluating the freezing impact on the proximate composition of immature cowpea (Vigna unguiculata L.) pods: classical versus spectroscopic approaches

Authors
Machado, N; Oppolzer, D; Ramos, A; Ferreira, L; Rosa, EAS; Rodrigues, M; Dominguez Perles, R; Barros, AIRNA;

Publication
JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE

Abstract
BACKGROUND: Freezing represents a common conservation practice regarding vegetal foodstuffs. Since compositional features need to be monitored during storage, the development of rapid monitoring tools suitable for assessing nutritional characteristics arises as a pertinent issue. In this study, cowpea (Vigna unguiculata L.) pods, both fresh and after 6 and 9 months of freezing at -18 degrees C, were evaluated by high-performance liquid chromatography for their content of protein as well as of essential and nonessential amino acids, while their Fourier transform infrared spectra in the mid infrared (MIR) and near infrared (NIR) ranges were concomitantly registered to assess the feasibility of this approach for the traceability of these frozen matrices. RESULTS: For the NIR interval, the application of the 1st derivative to the spectral data retrieved the best results, while for lower concentrations the application of the Savitzky-Golay algorithm was indispensable to achieve quantification models for the amino acids. MIR is also suitable for this purpose, though being unable to quantify amino acids with concentrations below 0.07 mmol g(-1) dry weight, irrespective of the data treatment used. CONCLUSIONS: The spectroscopic approach constitutes a methodology suitable for monitoring the impact of freezing on the nutritional properties of cowpea pods, allowing accurate quantification of the protein and amino acid contents, while NIR displayed better performance. (C) 2017 Society of Chemical Industry

2017

Front end of innovation: An integrative literature review

Authors
Pereira, AR; Pinto Ferreira, JJ; Lopes, A;

Publication
Journal of Innovation Management

Abstract
The beginning of the innovation process also known as Front End of Innovation (FEI) is an important contributor to the successful development of new products and the business success. The present study aims at giving an overview of how the FEI concept has been handled over the years, by identifying the focus of the research conducted in this domain knowledge. To this end, this study unfolds an encompassing perspective by developing an analysis of existing publications against two FEI Reference Models. This analysis comprised of the compilation, selection, and review of the content of 169 publications concerning the Front End of Innovation. The period of analysis covered all years until 2015. Evidence shows that this topic has received greater attention in the recent years both regarding depth and the number of publications. However, there are still pending gaps in the literature that are highlighted in this paper. The topics addressing organisational issues were the ones that received more attention.

2017

Virtual Enterprise integration management based on a Meta-enterprise - a PMBoK approach

Authors
Ferreira, L; Lopes, N; Avila, PS; Castro, H; Varela, MLR; Putnik, GD; Martinho, R; Rijo, R; Miranda, IM; Cruz Cunha, MM;

Publication
CENTERIS 2017 - INTERNATIONAL CONFERENCE ON ENTERPRISE INFORMATION SYSTEMS / PROJMAN 2017 - INTERNATIONAL CONFERENCE ON PROJECT MANAGEMENT / HCIST 2017 - INTERNATIONAL CONFERENCE ON HEALTH AND SOCIAL CARE INFORMATION SYSTEMS AND TECHNOLOGIES, CENTERI

Abstract
A Virtual Enterprise (VE) can be viewed as a project, with a lifecycle corresponding to the period between its creation and integration of the constituting elements until its dissolution, comprehending its operation and including its reconfigurations. The authors propose that the VE lifecycle is aligned and can be managed using the frameworks provided by several bodies of knowledge, such as the PMBoK Guide. In this paper the authors propose an alignment referential between the Project Management phases defined by PMBoK and management processes during the VE lifecycle. (C) 2017 The Authors. Published by Elsevier B.V.

2017

Multi-view data types for scalable concurrency in the multi-core era

Authors
Akkoorath, DD; Brandão, J; Bieniusa, A; Baquero, C;

Publication
PMLDC@ECOOP

Abstract

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