# DCORES 2015 Abstracts

Short Papers

Paper Nr: | 1 |

Title: | ## Ensuring Blood is Available When it is Needed Most |

Authors: | ## Nigel M. Clay, John Hearne, Babak Abbasi and Andrew Eberhard |

Abstract: | Past research conducted into the management and behaviour of blood inventories relies on distributional assumptions regarding the supply and demand for blood which tend to underestimate the true variation in inventory volumes. This may lead to the underestimation of blood shortages and outdates and/or give a false sense of security to inventory managers. This research will address this issue from a mathematical and modelling perspective and will use the results to examine the impact of alternative blood inventory policies. It is hypothesised that variation in blood inventories arises from two canonical sources. Firstly, the process of donation, storage, hospital orders, supply and transfusion consists of delays at several points. These delays can cause system oscillation and instability as a result of small changes in demand without the presence of stochastic variation in demand and supply. The second source of variation is the stochastic nature of demand and supply themselves. When considered together with the first source of volatility the total variation in the system may be amplified. It is believed that a model incorporating both of these sources of variation will exhibit the degree of volatility seen in the real data. Such a model could then be used to optimise inventory decisions or test the behaviour of the inventory to potential changes in blood storage, donor behaviour and so forth. |

Paper Nr: | 4 |

Title: | ## The Air Distribution Network Design Problem - A Complex Non-linear Combinatorial Optimization Problem |

Authors: | ## Sandy Jorens, Annelies De Corte, Kenneth Sörensen and Gunther Steenackers |

Abstract: | The objective of the air distribution network design optimization problem is to find the material and dimensions of each duct and fan in an air distribution network so that the total cost is minimized without violating aerolic constraints. Since the 1960s much research has been dedicated to the simulation and optimization of air distribution networks and numerous methods have been developed to solve this optimization problem. This paper aims to outline the current state-of-the-art in air distribution network design optimization and highlights the main shortcomings. Additionally, previous research is extended by presenting a model that integrates the network layout decisions into the optimization problem. In this problem, called the air distribution network design optimization problem the location of the fans and ducts in the network are determined so that the total cost of the network is minimized. This novel combinatorial optimization problem is characterized by discrete decision variables, and non-linear constraints. This paper also motivates the need for benchmark instances to evaluate the performance of existing or new developed optimization methods and advance future research in the field op air distribution network design optimization. A software tool is developed in this research to generate such instances. |