Can Automated Vehicles "See" in Minnesota? Ambient Particle Effects on LiDAR

(c)1035427This project will use a combination of laboratory experimentation and road demonstrations to better understand the reduction of LiDAR signal and object detection capability under adverse weather conditions found in Minnesota. It will also lead to concepts to improve LiDAR systems to adapt to such conditions through better signal processing image recognition software

[Drying] report /

Contract no. DA-18-064-CML-2408; Project no. 4-11-02-045; Mechanical Engineering Dept. Project no. 5192.Cooperative research program by University of Minnesota Institute of Technology, Dept. of Mechanical Engineering and Chemical Corps Biological Laboratories, DTF Division.Binder's title: Drying.Mode of access: Internet

Resolving nanoparticle growth mechanisms from size- and time-dependent growth rate analysis

Atmospheric new particle formation occurs frequently in the global atmosphere and may play a crucial role in climate by affecting cloud properties. The relevance of newly formed nanoparticles depends largely on the dynamics governing their initial formation and growth to sizes where they become important for cloud microphysics. One key to the proper understanding of nanoparticle effects on climate is therefore hidden in the growth mechanisms. In this study we have developed and successfully tested two independent methods based on the aerosol general dynamics equation, allowing detailed retrieval of time- and size-dependent nanoparticle growth rates. Both methods were used to analyze particle formation from two different biogenic precursor vapors in controlled chamber experiments. Our results suggest that growth rates below 10 nm show much more variation than is currently thought and pin down the decisive size range of growth at around 5 nm where in-depth studies of physical and chemical particle properties are needed.© Author(s) 201