Modeling is the most important task supporting our various activities: planning, right sizing of transport infrastructures, traffic management, technical and economic feasibility, comparison among different project solutions. Modeling allows to have a math tool estimating effects on traffic flows and on the environment caused by network configuration changes or by economic and demographic modifications; model effectiveness is based on its calibration using real data.
Aleph develops both macro or microsimulation models, depending on the studied scenario scale and accuracy. Macro models evaluate flows on the network in a specific time period both for private or public transport modes; macro- simulations are undertaken with specific software developed by Aleph itself or with commercial softwares. Micro-models, instead, allow to define dynamic vehicle interactions even in multi-modal scenarios. Environmental effects related to road infrastructure are studied in terms of traffic emissions: Aleph has developed a specific tool in order to offer a complete analysis to its clients.
Main activities are described below.
Traffic modeling:
- Network features and data representation by nodes and links; current and project scenarios configuration
- Demographic scenario elaboration
- Data collection and surveys (road traffic, passengers on board of PT, boardings, choice evaluation surveys)
- Four-step transportation forecasting model: Trip generation and distribution, mode choice modeling, route assignment
- Model calibration
- Graphic elaboration on GIS
Traffic emission models:
- Vehicle emissions description
- Weather data collection
- Background concentration of pollutants in the studied area evaluation