High Quality Content by WIKIPEDIA articles! TexSys is a web based application serving as a Texas Expert System for the selection of Hot-Mix Asphalt (HMA). TexSys is the product of a Texas Department of Transportation (TxDOT) study, TxDOT Project 0-4824: Guidelines for Selecting Asphalt Mixtures. It considers a number of factors (traffic volume and speed, desired performance characteristics, etc.) influencing the selection of HMA and recommends an asphalt mixture based on these. As such it is a tool for inexperienced or young engineers to assist them in selecting the right asphalt mixture for the job.