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Based on the sensitivity analysis and data obtained from a previous study were used in calibration of emission models for Indian conditions. It was found that operating weight, pavement gradient and vehicle life are very sensitive inputs into HDM-4 emission models. Initially sensitivity analysis of emission models was conducted to find sensitive input variables in emission model that affect model output significantly. The work presented here is an attempt to calibrate the HDM-4 emission models to Indian conditions.
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These models are required to be calibrated so that the predictions made by calibrated HDM-4 models represent the specific local ground conditions. There are seven exhaust emission models (for different components like hydro carbon, carbon monoxide, particulate emissions etc.) available within HDM-4. Exhaust emissions are one of the important outputs of vehicular performance models that are helpful in assessing viability of investment options and environment impact assessment activities. This tool has inbuilt pavement performance prediction models, vehicular performance models and economic analysis tools. AbstractThe Highway Development and Management-4 (HDM-4) tool has been widely used for the pavement management activities across the world.