Products
Optimal Pickup and Dropoff of Employees by a Fleet
A large call center in a major Indian city needed to optimize the use of its fleet of vehicles to pick up and drop off its employees prior to and on completion of their shifts. Since the workforce usually had an absence rate of 25%, a static solution to the problem was not feasible. Along with cutting costs, employee satisfaction was a major concern. We mapped the situation to a mathematical optimization problem where the roster of the shift was to be partitioned into vehicles and the route of the vehicle depended on the order of employee dropoffs. The additional time an employee spends in the vehicle, beyond the time needed for a direct dropoff, was considered a cost in terms of employee satisfaction. The optimization problem was a combination of two NP-complete problems and as a result, was not amenable to a direct solution. Effective approximation was achieved by use of a genetic algorithm and the results decreased the cost to one-third while retaining employee satisfaction at current levels.
Consulting
Route Rationalization for West Bengal Transport Department
The public transport network in Kolkata is vast and fragmented, being served by multiple government agencies and many private fleet owners. There was a need to consolidate routes and capacities among these operators to make the network efficient. To achieve this goal, each bus route was mapped by surveyors who marked the de facto trails and stops along with the number of passengers embarking and disembarking at each stop. This data was used to create a geographic and topological model of the bus network. Route sections were characterized and origin-destination level demand was inferred using Monte-Carlo techniques. Routes we then rationalized based on recommendations to merge, extend, or split routes using graph-theoretic measures. The results were presented to Transport Department officials and have since been implemented. This study was undertaken on behalf of the World Bank Group.