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Publications

Publications by SYSTEM

2018

Kidney Exchange Programs with a Priori Crossmatch Probing

Authors
Alvelos, F; Viana, A;

Publication
OPERATIONS RESEARCH PROCEEDINGS 2017

Abstract

2018

Using Metalearning for Parameter Tuning in Neural Networks

Authors
Felix, C; Soares, C; Jorge, A; Ferreira, H;

Publication
VIPIMAGE 2017

Abstract
Neural networks have been applied as a machine learning tool in many different areas. Recently, they have gained increased attention with what is now called deep learning. Neural networks algorithms have several parameters that need to be tuned in order to maximize performance. The definition of these parameters can be a difficult, extensive and time consuming task, even for expert users. One approach that has been successfully used for algorithm and parameter selection is metalearning. Metalearning consists in using machine learning algorithm on (meta)data from machine learning experiments to map the characteristics of the data with the performance of the algorithms. In this paper we study how a metalearning approach can be used to obtain a good set of parameters to learn a neural network for a given new dataset. Our results indicate that with metalearning we can successfully learn classifiers from past learning tasks that are able to define appropriate parameters.

2018

A Decision-Support System for Preventive Maintenance in Street Lighting Networks

Authors
Carneiro, D; Nunes, D; Sousa, C;

Publication
Hybrid Intelligent Systems - 18th International Conference on Hybrid Intelligent Systems, HIS 2018, Porto, Portugal, December 13-15, 2018

Abstract
An holistic approach to decision support systems for intelligent public lighting control, must address both energy efficiency and maintenance. Currently, it is possible to remotely control and adjust luminaries behaviour, which poses new challenges at the maintenance level. The luminary efficiency depends on several efficiency factors, either related to the luminaries or the surrounding conditions. Those factors are hard to measure without understanding the luminary operating boundaries in a real context. For this early stage on preventive maintenance design, we propose an approach based on the combination of two models of the network, wherein each is representing a different but complementary perspective on the classifying of the operating conditions of the luminary as normal or abnormal. The results show that, despite the expected and normal differences, both models have a high degree of concordance in their predictions. © 2020, Springer Nature Switzerland AG.

2018

The influence of external factors on the energy efficiency of public lighting

Authors
Carneiro, D; Sousa, C;

Publication
Atas da Conferencia da Associacao Portuguesa de Sistemas de Informacao

Abstract
LED-based technology is transforming public lighting networks, favouring smart city innovations. Beyond energy efficiency benefits, LED-based luminaries provide real time stateful data. However, most of the municipalities manage all their luminaries equally, independently of its state or the environmental conditions. Some existing approaches to street lighting management are already considering elementary features such as on-off control and individual dimming based on movement or ambient light. Nevertheless, our vision on public (street) lighting management, goes beyond basic consumption monitoring and dimming control, encompassing: a) adaptive lighting, by considering other potential influence factors such as work temperature of the luminaries or the arrangement of the luminaries on the street; b) Colour tuning, for public safety purposes and; c) emergency behaviour control. This paper addresses the first component (adaptive lighting) influence factors, in the scope of a real scenario in a Portuguese municipality.

2018

Industry 4.0 in Tamega e Sousa's region in a twofold perspective: industry vs IT enterprise

Authors
Freitas, R; Sousa, C;

Publication
2018 13TH IBERIAN CONFERENCE ON INFORMATION SYSTEMS AND TECHNOLOGIES (CISTI)

Abstract
The 4th industrial revolution is forcing industry towards its technological, productive and human requalification. In this paradigmatic shift, technology plays a key role and organisations must know, understand and dominate the intricacies of industry 4.0. However an issues arises: aren't we putting technology ahead of the processes ?. The truth is that 140 project are being implemented in different velocities in different companies and regions, even a small country like Portugal. Actually, despite of industries leaders agreed on the importance of the technological requalification (maybe pushed by the mediatism of the 4th industrial revolution), there is a lack of installed capability to embrace such projects. This concern is amplified when considering Portuguese sub regions. The impact of the 140 concept in the Portugues sub regions is the main motivation for his study on the Tamega e Sousa region. The study combines the perspective/situation of the industry and the software houses.. The way the 14.0 concept is being understood by the organisations in the Tamega and Sousa region, and the degree of preparation for the phenomenon is discussed in this paper. The awareness of the lack of preparation of the organisations for the adoption of 140. strategies or 14.0 projects 14.0, together with the inability of the region's software houses to reverse this situation, led to the presentation of a practical set of recommendations. The framework of recommendations pragmatically translates the different dimensions associated with the challenges inherent in 14.0.

2018

eCommerce Business-to-Business platform for the footwear sector: The cluster of Felgueiras

Authors
Ribeiro, SP; Santos, VR; Pereira, CS;

Publication
2018 13TH IBERIAN CONFERENCE ON INFORMATION SYSTEMS AND TECHNOLOGIES (CISTI)

Abstract
The Portuguese footwear industry is aware that success in the value chain is directly tied to information sharing and the development of collaborative networks, which are consequences of the constant rapid market changes. In this paper a state-of-the-art of the Portuguese footwear sector is presented, giving special focus to the cluster of Felgueiras and the good practices that are applied to it. Next, B2B and eCommerce domains will be discussed, as well as the good practices and information systems that support them. Afterwards, a list of functional and non-functional requirements, which have been validated and prioritized using a case studies approach, will be presented. Finally, it will be presented a non-functional prototype for an eC-B2B platform for the footwear sector.

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