Fradinho, Andre, Maria Isabel Gomes, and Ana Paula Barbosa-póvoa. Optimization of Batteries Sustainable Distribution Network with Reverse Flows In
Livro de actas do 15º congresso da APDIO, IO2011. Coimbra, Portugal, 2011.
AbstractOptimized supply chains, both economically as well as environmentally, are significant instruments to be adopted by companies if they want to succeed in the current competitive world. However, without the support of decision tools to help, at least approximately, the integration of these two aspects in the company’s decision making such aim is difficult to reach. The purpose of this study is to develop a mixed integer linear programming model (MILP), which allows the optimization of closed loop supply chains, considering not only economical aspects, but also environmental ones. The model developed was applied to a Portuguese company where their logistic network structure was redesigned.
Gomes, Isabel M., Luis J. Zeballos, Ana P. Barbosa-Povoa, and Augusto Q. Novais. "
Optimization of Closed-Loop Supply Chains under Uncertain Quality of Returns." In
21st European Symposium on Computer Aided Process Engineering, edited by E. Pistikopoulos, M. C. Georgiadis and A. Kokossis, 945-949. Vol. 29., 2011.
AbstractThe efficient design and operation of supply chains with return flows represent a major optimization challenge, given the high number of factors involved and their intricate interactions. In particular, the quality level of the return products has strong economic and societal implications and depends greatly on the type of product (glass, paper, electronic, oil, etc) and on the degree of consumers’ readiness, frequently promoted by various kinds of awareness raising campaigns. A multi-product multi-period model was previously developed by the authors [1] for the closed-loop supply chain (CLSC) design and planning, where strategic and tactical decisions were comprehensively considered. This model is now being extended to handle the uncertainty related to the quality of the returned products, which at this stage is modeled by a two-stage scenario-based stochastic approach. General strategies to solve optimization problems involving uncertainty tend to exhibit poor computational performance, due to the problem NP-hard complexity, which tends to worsen with the problem size. Therefore and, in addition, a model performance solution enhancement is also being explored. To increase the efficiency of the solution approach, an alternative representation to some of the integer variables employed in the mathematical formulation was developed, which is tested by means of computational experiments being performed on illustrative real sized examples.
Zeballos, L. J., M. I. Gomes, A. P. Barbosa-Povoa, and A. Q. Novais. "
Optimum Design and Planning of Resilient and Uncertain Closed-Loop Supply Chains." In
22nd European Symposium on Computer Aided Process Engineering, edited by Ian David Lockhart Bogle and Michael Fairweather, 407-411. Vol. 30. Computer Aided Chemical Engineering 30. London: Elsevier, 2012.
AbstractThe design and planning of efficient supply chains (SC) is a major challenge that increases when the return of products has to be accounted for, the so-called closed-loop supply chains (CLSC). In the present work the effect of disruptions and modifications in the operating conditions of CLSCs are investigated on the basis of a 2-stage scenario based model previously developed by the authors. Metrics derived from graph theory are used, along with more conventional economic and operational indices. A discussion on the results obtained is presented to assess how the design and planning of the CLSC respond to these challenges and how these metrics may contribute to this objective.