Reconsideration of optimization for reduction of traffic congestion

One of the most impressive applications of a quantum annealer was optimizing a group of Volkswagen to reduce traffic congestion using a D-Wave system. A simple formulation of a quadratic term was proposed to reduce traffic congestion. This quadratic term was useful for determining the shortest routes among several candidates. The original formulation produced decreases in the total lengths of car tours and traffic congestion. In this study, we reformulated the cost function with the sole focus on reducing traffic congestion. We then found a unique cost function for expressing the quadratic function with a dead zone and an inequality constraint.