A surrogate-assisted measurement correction method for accurate and low-cost monitoring of particulate matter pollutants

Air pollution involves multiple health and economic challenges. Its accurate and low-cost monitoring is important for developing services dedicated to reduce the exposure of living beings to the pollution. Particulate matter (PM) measurement sensors belong to the key components that support operation of these systems. In this work, a modular, mobile Internet of Things sensor for PM measurements has been proposed. Due to a limited accuracy of the PM detector, the measurement data are refined using a two-stage procedure that involves elimination of the non-physical signal spikes followed by a non-linear correction of the responses using a mul-tiplicative surrogate model. The correction layer is derived from the sparse and non-uniform calibration data, i. e., a combination of the measurements from the PM monitoring station and the sensor obtained in the same location over a specified (relatively short) interval. The device and the method have been both demonstrated based on the data obtained during three measurement campaigns. The proposed correction scheme improves the fidelity of PM measurements by around two orders of magnitude w.r.t. the responses for which the post -processing has not been considered. Performance of the proposed surrogate-assisted technique has been favor-ably compared against the benchmark approaches from the literature.

Automated summary

Air pollution poses multiple challenges to health and economy, making accurate and low-cost monitoring critical. This study introduces a modular, mobile Internet of Things sensor for particulate matter measurements. A two-stage procedure is used to refine measurement data and improve accuracy with a correction model based on calibration data.