Optimization of Dynamap noise mapping predictive scheme in Milan urban area

Dynamap, a co-financed project by the European Commission through the Life+ 2013 program, aims at developing a dynamic approach to noise mapping based on a limited number of noise monitoring stations. Dynamap is based on the idea of finding a suitable set of roads that display similar traffic noise behaviour so that one can group them together into a single noise map. The applicability of Dynamap is based on an available non-acoustic information on each road segment of the area under study. According to the chosen non-acoustic parameter, each road stretch presents a noise temporal profile that could be described as a combination of the two main noise behaviour. Each group of roads can, therefore in principle, be represented by the same acoustic map. For the effective implementation of Dynamap, we, initially, decided to divide the entire range of available non-acoustic parameter into six intervals, called groups, each one described by a noise base map and described by four monitoring sensors. The noise in a given location is therefore predicted by a combination of the six acoustic base noise maps whose variation (dynamic feature) are provided by the monitoring stations. In this paper, we discuss a second procedure for updating the acoustic maps based on a two-cluster expansion scheme performed directly over the noise recorded by the 24 monitoring sensors.