Projects
Short-term Demand and Supply Forecasting for Bike Taxis
Bike taxis have become a popular transport option, nowhere more so than in Indonesia where consolidating bike taxis into an app-based platform resulted in the first tech unicorn in the country. However, predicting the fluctuating demand and corresponding in a large city is challenging - especially since the desire for bike rides is strongly connected to the weather in tropical regions. A model to forecast the local demand and supply for the upcoming fifteen minutes was requested, based on current and historic data. The problem was divided into segments: the demand was predicted based on historical information, current trend, and weather information; the supply was predicted based on the historical driver tendencies, the current locations of drivers, and the estimated endpoints of currently active rides. Neural networks and Markov chains were employed to arrive at a model with around 90% forecast accuracy.
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.
Estimated Time of Arrival of Public Transport Vehicles to Stops
An application, sponsored by the World Bank Group, was developed to track all public transport vehicles in the city of Kolkata and disseminate their locations to citizens. As part of the implementation, a model was developed to accurately estimate the time of arrival of vehicles to stops, providing citizens to use this information about their choice of travel mode. The model used existing information collected from the buses during their travels and incorporated additional information related to the day of the week, time of day, weather conditions as well as special occasions. The network of routes was divided into route segments and duration was estimated for each segment. The base model was subsequently enhanced by incorporating the time of the most recent vehicles to traverse the segment weighted by recency. The model was incorporated into the application and citizens have enjoyed the benefits of the estimates since 2017.
Consulting
Freight Assessment for Regional Waterway Connectivity
The technical, socio-economic, and logistical aspects of constructing a new canal to establish a direct inland connection between the Hooghly/Ganga River in India and the Padma River in Bangladesh, led to modeling the impact of the proposed canal on the pattern of transportation. The canal would not only be effective to divert a significant amount of traffic from the current land routes used for India-Bangladesh trade but could potentially divert trade from the North-East region to the rest of India. Data was collected from various government sources and trade-route partitioning was modeled based on the origin and destination of goods and the border crossing chosen for each goods category. The result was then mapped to a new potential waterway channel and the potential transition was estimated. This result was then forecast for the next thirty years.
Optimizing Electric Buses Routes by Monitoring Local Air Quality
The introduction of electric buses in Kolkata required planning the routes of greatest impact as well as the convenience of being within reasonable proximity to charging stations. The environmental impact required a study of hyperlocal fluctuations in air quality, especially in particulate matter across the city. For this purpose, custom low-cost air quality monitors were designed and manufactured, and calibrated by co-locating with reference grade sensors maintained by the Pollution Control Board. These sensors were placed at select locations across the city and their data was continuously captured in the cloud for over one year. Along with the information obtained from the network of reference-grade sensors, we developed a spatio- temporal dispersion model to interpolate and map the pollution levels across the city. Fluctuations and hotspots identified from this result were overlayed with the previously modeled demand to select the first two high-impact electric bus routes in the city.
Intra-City Freight Flow in the City of Kolkata
Fright transport around the city of Kolkata is complicated by the presence of River Ganges which requires traversal of the river across two main bridges resulting in congestion and delays. The World Bank Group intended to build roll-on/roll-off jetties at several locations to augment the available routes for trucks to cross the river. A study was commissioned to identify the impact of intra-city freight movement in the city of Kolkata as a result of these new crossings. The city was geographically divided into natural regions demarcated by canals or railway lines such that there were limited ways to cross from one region to the other. At each crossing, surveyors counted all goods transport vehicles while also recording their size and the type of goods carried. The survey lasted one week at each location, twenty-four hours a day. An additional survey was conducted at each large market in the city to interview shop owners to gauge and understand delivery patterns. The results were combined into a topological model which resulted in a visualization of the intra-city traffic flow by type of goods and vehicles across time and day of the week. As a result, the model could deliver a view of the potential consequences of local disruptions and deviations and was used to plan the location of the proposed jetties.
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.