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Details

  • Name

    Flávia Barbosa
  • Role

    Assistant Researcher
  • Since

    22nd April 2016
004
Publications

2024

Optimisation models for project selection in asset management: an application to the water sector

Authors
Vilarinho, H; Barbosa, F; Nóvoa, H; Silva, JG; Yamada, L; Camanho, AS;

Publication
INTERNATIONAL TRANSACTIONS IN OPERATIONAL RESEARCH

Abstract
A significant challenge in asset management is the selection of investment projects for infrastructures, which often relies on subjective judgement and lacks structured decision support methods. This challenge is particularly complex in water systems due to the diverse and heterogeneous nature of the components requiring investment. While the infrastructure value index (IVI) is widely used to characterise assets and support investment decisions in the water sector, its application in optimisation models for generating efficient project portfolios remains unexplored. To address this research gap, this study introduces optimisation models for generating investment portfolio plans in water systems' asset management. The proposed approach includes two mixed-integer linear programming (MILP) models that determine optimal solutions and an evolutionary algorithm that offers sub-optimal alternative investment selection plans to provide decision-makers with additional choices for balancing optimal outcomes. The primary contribution of this research is the combined utilisation of MILP and evolutionary algorithms, integrating the IVI into the decision-making process. These tools provide decision-makers with structured methods for defining investment plans and minimising the subjective elements typically associated with such processes. To illustrate the effectiveness of the models, a case study is presented involving a pumping station of a Portuguese water company. The results demonstrate the practical application and benefits of the proposed approach in optimising investment decisions. This research contributes to advancing asset management practices by integrating quantitative optimisation techniques and leveraging the IVI, thereby enhancing the objectivity and efficiency of investment planning in water systems' asset management.

2024

The impact of the single supervisory mechanism on Eurozone banking: the assessment of trends in efficiency and frontier position

Authors
Moura, P; Barbosa, F; Alves, C; Camanho, AS;

Publication
APPLIED ECONOMICS

Abstract
The Single Supervisory Mechanism (SSM) was implemented as a first step towards a Banking Union in November 2014. This paper investigates the impact of the SSM on Eurozone banks' efficiency and position of best-practice frontier. It is based on a balanced panel analysis of 931 European bank-year observations from 2011 to 2017 (133 banks, seven years). The study uses Data Envelopment Analysis and a difference-in-differences approach to explore the evolution of banking performance. We found that the SSM had a negative impact on the efficiency levels of Eurozone banks, particularly in the year after the introduction of the mechanism. Additionally, we observed that the frontier formed by non-Eurozone European Union banks is more productive than the frontier of Eurozone banks in all the years analysed. Both efficiency and frontier position show evidence of a recovery trend in more recent years for both groups. We also found that while Equity-to-Asset Ratio, Return on Average Assets and Gross Domestic Product per capita positively impacted banks' efficiency, domestic credit provided by banks expressed as %GDP had a negative impact on efficiency.

2024

Performance evaluation and benchmarking to inform dispatching rules for hydropower plants

Authors
Barbosa, F; Casacio, L; Bacalhau, ET; Leitao, A; Guimaraes, L;

Publication
UTILITIES POLICY

Abstract
Hydropower currently generates more than all other renewable energies combined. Considering the challenges of climate change and the transition to green energy, it is expected to remain the world's largest source of renewable electricity generation. This paper proposes a tool for performance evaluation and benchmarking of hydropower generation to inform dispatching. Through them, strengths and weaknesses of asset operations can be set, identifying areas with the best performance, gathering insights from their strategies and best practices, and comprehending factors that lead to variations in performance levels. The results allow for optimising energy resource use by indicating the dispatching rules with maximum power production and minimum wearand-tear impact. This framework allows the formulation of practical guidelines for dispatching policies. The proposed methodology is applied to analyse two real-world case studies: the Vogelgr & uuml;n run of river hydropower plant (France) and the Frades 2 pump-storage powerplant (Portugal).

2024

Modeling and Optimizing Sugarcane-Livestock Integration Systems in Brazil

Authors
Dias, LR; Cardoso, F; Jimenez, CM; Marques, GO; Barioni, G; Barbosa, F; Mariano, P; Cunha, P; Bonomi, A;

Publication
Computer Aided Chemical Engineering

Abstract
The expansion of ethanol production in Brazil sparks several sustainability concerns, including debates on “food versus fuel”, the environmental impacts of monocultures, and indirect land-use change. Since livestock farming occupies a significantly greater area than sugarcane for ethanol production in Brazil and has a large yield gap, sugarcane-livestock integration can be a promising alternative. This integrated system considers crop production systems, biorefinery processing and meat production in both intensive and extensive livestock farming. Optimizing this system for both economic and environmental aspects can be challenging to implement and computationally expensive as this system's complexity arises from nonlinear subsystems and their intertwining input-output flows. For these reasons, this paper develops metamodels from detailed models to: (i) Optimize the extensive livestock farming, (ii) Optimize the confined animal feeding, and (iii) Optimize the integrated system. The main objective is to maximize the Net Present Value relative to investment. This study contributes to the literature by developing innovative models for ethanol-beef integrated production systems and methods for optimizing such systems to avoid negative externalities on food security and environmental impacts. © 2024 Elsevier B.V.

2024

Improving asset management in capital-intensive industries: Case study of a Portuguese water utility

Authors
Casalta, M; Barbosa, F; Yamada, L; Ramos, LB;

Publication
UTILITIES POLICY

Abstract
The efficient management of assets delivers value and is essential for achieving service objectives, managing risks, and reducing costs. This paper proposes decision-support methods to help capital-intensive industries manage their assets and optimise their life cycle. Optimisation approaches were developed to support longterm investment planning by maximising the value created and minimising the budget used. Also, the trade-off for both objectives was analysed. Using the proposed models will lead to efficient management of available capital and excellent service delivery. Thus, water companies will fulfil the regulator's requirements and present well-founded decision-making. This study was applied to a Portuguese water utility.

Supervised
thesis

2023

Location Intelligence: an integrated Decision Support System for improved infrastructure placement

Author
Gonçalo Filipe Ferreira Rodrigues

Institution
UM

2023

A robust conditional assessment of European regions' performance in light of the 2030 Strategic Framework for Education and Training

Author
Maria João Araújo Durães

Institution
UM

2023

Implementation of a KPI tree for shopfloor management and resource allocation

Author
Miguel Ferreira Branco

Institution
UM

2023

Suporte à Otimização de uma Rede de Balcões com recurso a informação em Tempo Real

Author
Francisco António Beleza Braga

Institution
UM

2022

Estudo do Impacto da Centralização de Armazéns Retalhistas

Author
Ana Sofia de Vasconcelos Peixoto Fonseca

Institution
UM