There is a lack of affordable access to many important medications in the Arab world. Some of these medications are available in neighboring countries at reasonable prices. Our project Tabadol takes advantage of existing transport between the countries and quantum optimization algorithms to efficiently distribute these crucial medications at a reasonable price.
Our solution has three components.
First, we developed an app that informs travelers of medications in need in the region and allows users in need of medication to make requests.
In this application, users are able to request medications that are unavailable or inaccessibly priced in their region.
Travelers who may have access to these medications are also able to register their flights so that our application can determine if there are any medications they could bring with them for those who need them. Travlers will be compensated for this assistance
Finally, the application takes all of the travelers and which medications they have access to as well as all of the customers and medications that they need and determines which medications travelers should pick up and how these can be optimally delivered to customers.
Next, there are many constraints on travelers on what medications they can travel with as well as space and weight constraints in terms of what they can add to luggage. Certain medications may also be needed more urgently than others. When there are many people in need of medication and many medications in the system, this optimization problem is complex. We can solve this problem as a knapsack problem on quantum hardware.
Additional details can be found in multiple_knapsack.ipynb
Finally, to minimize the cost of medications and take advantage of this opportunity for arbitrage, transport of medications from airports to consumers must be as efficient as possible. We solve this problem as a vehicle routing problem where the objective is to minimize the overall cost of deliveries given a fleet of vehicles with limited capacities. We formulate this as a VQE algorithm which is solved using quantum annealing with D-Wave's superconducting hardware.
Additional details including a mathematical analysis can be found in vrp_constrained.ipynb
The multiple knapsack and constrained vehicular routing problems are both classically NP-Hard problems. However, using quantum computing, the solutions to these problems can be closely approximated in polynomial time. Using the variational quantum eigensolver (VQE) and the quantum unconstrained binary optimization (QUBO) formulation of these problems, we were able to achieve fast and accurate results for small representative examples of the knapsack and routing problems on D-Wave's superconducting hardware using quantum annealing.
Presentation: https://docs.google.com/presentation/d/1OoKNzceWWOMCj25XLEFtdThU6Msp-h_bmv9lNhq2nsM/edit#slide=id.p
This work takes inspiration from the following works:
Borowski, M. et al. (2020). New Hybrid Quantum Annealing Algorithms for Solving Vehicle Routing Problem. In: Krzhizhanovskaya, V., et al. Computational Science – ICCS 2020. ICCS 2020. Lecture Notes in Computer Science(), vol 12142. Springer, Cham. https://doi.or/g10.1007/978-3-030-50433-5_42
Awasthi, A., Bär, F., Doetsch, J., Ehm, H., Erdmann, M., Hess, M., Klepsch, J., Limacher, P.A., Luckow, A., Niedermeier, C., Palackal, L., Pfeiffer, R., Ross, P., Safi, H., Schönmeier-Kromer, J., von Sicard, O., Wenger, Y., Wintersperger, K. and Yarkoni, S. (2023). Quantum Computing Techniques for Multi-Knapsack Problems. [online] arXiv.org. Available at: https://arxiv.org/abs/2301.05750 [Accessed 28 Apr. 2024].