How to Optimise Investments in the Network of Medical Centres Along the African Highways

This thesis describes the possibilities to model and solve the problem of investing optimally in a network of medical centres, called Roadside Wellness Centres (RWCs), along the African highways. By placing new RWCs at busy truck-stops, one intends to increase the number of truck drivers which have access to medical service. Next to that, the investments should create a network of RWCs, in which the truck drivers are provided with a continuum of care. This means that truck drivers, who suddenly need medical help, do not need to drive a long time along their routes before passing an RWC. In order to realise these goals, two MIP models are proposed in this thesis. The RWC Investment Model (RIM) models the problem of allocating locations to p new RWCs. The objective is to do this in such a way that the expected number of patients visiting the RWCs is maximised and that the expected time to the next RWC passed by an African truck driver is minimised. This model can be classified into the flow coverage models that also maximise the node demand covered. The RIM is extended to the RWC & Staff Investment Model (RSIM), which models the problem of optimally investing a budget increase by establishing new RWCs and hiring new employees. Both the RIM and the RSIM are extended so that de-investments can be optimised too. A case study shows that these models increase the benefits of investments a lot compared to the current investment strategy. The models can solve a large problem instance within an acceptable time. The sensitivity of the optimal solution to noise in the main input data and to changes in the user-defined parameters is analysed.