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Publications

Publications by SYSTEM

2019

Analysis and Implementation of a Lean Model in Warehouse Management

Authors
Gonçalves, José; Bastos, João; Ávila, Paulo;

Publication
PROCEEDINGS of 2100 Projects Association Joint Conferences

Abstract
This project aimed to analyze the practical difficulties in storing and moving a high range of products making the process easier and more efficient. The objectives were to improve the use of available space in the raw materials warehouse and ensure the effectiveness, efficiency and reduction of the periods between the transportation from raw materials to production lines. The work developed focused on improving internal processes, storage practices and internal transportation. In fact, for the production flow to be continuous, the supply must be aligned with the production to ensure that there is no failure of materials.

2019

Maximizing the expected number of transplants in kidney exchange programs with branch-and-price

Authors
Alvelos, F; Klimentova, X; Viana, A;

Publication
ANNALS OF OPERATIONS RESEARCH

Abstract
In this paper, we propose a branch-and-price approach for solving the problem of maximizing the expected number of transplants in Kidney Exchange Programs (KEPs). In these programs, the decision on which transplants will be conducted is usually made with the support of optimization models with the assumption that all operations will take place. However, after a plan of transplants is defined, a pair may leave the KEP or a more accurate compatibility evaluation exam may invalidate a transplant. To model these possible events we consider probabilities of failure of vertices and of arcs and the objective of maximizing the expected number of transplants. The proposed approach is based on the so-called cycle formulation, where decision variables are associated with cycles. Built on the concept of type of cycle a branch-and-price algorithm is conceived. One subproblem is defined for each type of cycle. We present computational results of the proposed branch-and-price algorithm and compare them with solving directly the cycle formulation (with a general purpose mixed integer programming solverCPLEX) showing that the proposed approach is the only one suitable for larger instances.

2019

Robust cepstral-based features for anomaly detection in ball bearings

Authors
Sousa, R; Antunes, J; Coutinho, F; Silva, E; Santos, J; Ferreira, H;

Publication
INTERNATIONAL JOURNAL OF ADVANCED MANUFACTURING TECHNOLOGY

Abstract
This paper proposes the linear frequency cepstral coefficients as highly discriminative features for anomaly detection in ball bearings using vibration sensor data. These features are based on cepstral analysis and are capable of encoding the patterns of a spectral magnitude profile. Incipient damages on bearings can grow rapidly under normal use resulting in vibration and harsh noise. If left undetected, this damage will worsen, leading to high maintenance costs or even injury. Multiple interferences in an industrial environment contaminate the signal, making it a challenge to correctly identify the bearings' condition. Many studies have attempted to overcome this issue at the signal level. However, the discriminative capacity of the current vibration signal features is still vulnerable to interference, which motivates this work. In order to demonstrate the benefits of these features, we (1) show that they are computationally efficient and suitable for real-time incremental training; (2) conduct discriminative analysis by evaluating the separability performance and comparing it with the state of the art; and (3) test the robustness of the proposed features under noise interference, which is ideal for use in the harsh operating conditions of industrial machinery. The data was obtained from a laboratory workbench setting that reproduces bearing fault scenarios. Results show that the proposed features are fast, competitive when compared to state-of-the-art features, and resilient to high levels of interference. Despite the higher performance when using the quadratic model, the proposed features remain highly discriminative when used with several other discriminant function.

2019

Knowledge-intensive services for regional innovation The case of a NUTIII region in Portugal

Authors
Azevedo, A; Sousa, C; Duarte, N; Pereira, C; Souesa, C; Peraira, C;

Publication
2019 14TH IBERIAN CONFERENCE ON INFORMATION SYSTEMS AND TECHNOLOGIES (CISTI)

Abstract
Innovation stills on the world's agenda as the holy grail of business success. Nevertheless, it stills hard for some communities to understand and embrace innovation processes in a systematic way as a continuum for regional development. Our stance is that innovation seeds, feeds innovation. That means, innovation won't work in a closed cycle, but rather in an open and cross-entity manner, forming a knowledge-managed regional development ecosystem. Accordingly, this paper describes a knowledge lab, designed as an intel structure to offer knowledge-intensive services towards the regional development of the "Tamega e Sousa" (NUTIII) Region. This knowledge lab aims at complementing the installed dynamics on innovation support and economic stimulus in a knowledge-based innovation management approach.

2019

Internationalization and Higher Education

Authors
Nogueira, R; Moreira, AC;

Publication
Higher Education and the Evolution of Management, Applied Sciences, and Engineering Curricula - Advances in Higher Education and Professional Development

Abstract
Education is the most successful strategy for a country's growth and development. It is widely agreed that it is the most effective means that society possesses for dealing with the challenges of the future. Nevertheless, higher education has been confronted and needs, therefore, to redefine its historic role as the center of universal knowledge and understanding. This chapter analyzes the importance of internationalization on higher education institutions and enable us to better understand how they are changing as a consequence of the globalization process. Using the University of Aveiro as a case study, we will be studying what internationalization is in a higher education context and which rationales, approaches, and activities are associated with the internationalization process. Furthermore, the appropriateness of theories of internationalization specifically developed for business contexts will be portrayed at the end of the chapter.

2019

Strategic fit between innovation strategies and supply chain strategies: a conceptual study

Authors
Zimmermann, R; Ferreira, LMDF; Moreira, AC;

Publication
INTERNATIONAL JOURNAL OF VALUE CHAIN MANAGEMENT

Abstract
Considering the importance of innovation and supply chain (SC) management for firms' competitiveness and the growing interest for the relationship between these two areas, this conceptual paper aims to answer the following research question: how does the fit between the different innovation strategies and SC strategies influence business performance? A literature review was conducted as the basis for developing a conceptual framework, using the principles of resource-based view and contingency theory. Different innovation and SC strategies are studied and discussed with respect to the expected effects of fit on business performance. Five propositions and a conceptual framework are presented showing the complexity of the relationship between both strategies. The conceptual model put forward helps to advance research in the area allowing for an interrelationship between innovation and SC strategies, something that has not been adequately researched, and provides insights for managers who are seeking substantive improvement of business performance.

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