Chair: Pedro Martins, Polytechnic Institute of Coimbra and CIO, Portugal
Planning production and workforce in a discrete-time financial model: optimizing cash-flows released
Pedro Martins (email@example.com)
Production planning interacts with a number of functional aspects within the entire system of a company. Two of those aspects involve workforce and financial planning. In effect, growing production amounts may demand further workforce, which increases financial costs. On the contrary, lower levels of production may decrease workforce needs, while possibly resulting in lower financial incomes. So, there should exist an adequate balance on the production levels such that the cash-flows can generate the highest returns, along the entire financial stream. This suggests that these three elements of the system (production, workforce and cash-flows) are tightly connected, and that they should be planned together. This paper discusses this interaction, proposing a mixed integer linear programming formulation for a general outline of this three elements system. In order to simplify the discussion, while focusing in the interaction, we consider a sing-product in a capacitated production process. Decisions involving cash-flows released along the planning horizon are also incorporated, including dividends payments, allowing the system do decide when and how much should be released outwards such that a given sustainability condition or a final outcome condition is met.
Keywords: Production planning, Workforce planning, Financial planning
Influence of Corporate Social Responsibility on economic performance within supply chain planning
Bruna Mota (firstname.lastname@example.org), Maria Isabel Gomes (email@example.com), Ana Carvalho (firstname.lastname@example.org), Ana Barbosa-Póvoa (email@example.com)
This work aims to study the economic impact of incorporating corporate social responsibility issues on supply chain design and planning. A mathematical programming model that allows the optimal design and planning of supply chains is developed. A social benefit indicator is established where the regional development of less developed regions is intended. The supply chain is optimized under two different objective functions: economic and social. The model is applied to a case-study developed in collaboration with a Portuguese battery producer.
Keywords: Supply chain, Planning, Corporate social responsibility
Airport ground movement scheduling
Filipe Carvalho (firstname.lastname@example.org), Miriam Lobato (email@example.com), Ana Sofia Pereira (firstname.lastname@example.org)
Worldwide air traffic tends to increase and for many airports its no longer an option to expand terminals and runways, so airports are trying to maximize their operational efficiency. Another fact is that many airports already operate near their maximum capacity. Peak hours imply operational bottlenecks and cause chained delays across flights impacting passenger, airlines and airports. There are three major problems concerning airport operations: the departures and arrivals sequencing on the runways; the staff management operations preceding the green light for aircraft to leave the gate; and the ground movement between the gate and the runway (and reverse). The scope of this work is the ground movement problem that interacts with the other two scheduling systems mentioned and provides decisions in real-time. The ground movement problem consists of scheduling the path along a taxiway for a plane moving from the gate to the runway for takeoff, or on the reverse path after landing. Our approach proposes an online optimization system that considers a set of planes moving to and from a set of runways along a given road network conditioned by the airport ground layout. It considers constraints such as the route taken, separation between aircraft due to jet blast, aircraft movement speeds, timing constraints for arrivals and departures in a constantly changing environment. The objective is to minimize fuel consumptions on the ground (from the airline perspective) and to minimize the time spent on the time window slot for occupying the airport ground (from the airport perspective) while granting all safety regulations at all times. Also passengers and the environment benefit from an optimized ground movement. The optimization approach proposed provides a fast heuristic solution for each real-time event generated with respect to the Advanced Surface Movement, Guidance and Control Systems (A-SMGCS) of the International Civil Aviation Organization (ICAO).
Keywords: Airport operations, Ground movement, Scheduling