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Radar Polarimetry for Rain Estimation
Published in Ni-Bin Chang, Yang Hong, Multiscale Hydrologic Remote Sensing, 2012
The disdrometer is an effective tool for rain microphysical study, because it can measure DSDs. The traditional disdrometer is the impact type (e.g., Joss–Waldvogel disdrometer), which is designed based on the measurement of raindrop momentum (Tokay et al. 2001). Recent disdrometers apply the optical technique, for example, the one-dimensional laser optical disdrometer (Parsivel disdrometer) and the two-dimensional video disdrometer (2DVD; Kruger and Krajewski 2002). The disdrometer with the optical technique provides not only more accuracy but also additional measurements of the shapes and falling velocities of the raindrops.
Electrostatic precipitator dust density measurements in a Mars-like atmosphere
Published in Particulate Science and Technology, 2021
Beverly W. Kemmerer, John E. Lane, Jerry J. Wang, James R. Phillips, Michael R. Johansen, Charles R. Buhler, Carlos I. Calle
The purpose of this paper is to describe a dust measurement methodology that was applied to the Mars electrostatic precipitator (MEP) developed at the Kennedy Space Center (KSC). This dust measurement technique was modified from previous work where both particle counting in size bins and laser extinction were used (Lane et al. 2016). The previous work involved a different geometry and therefore the measurement methodology was developed to match that configuration, a 8 m × 8 m × 4 m rectangular dust bin, containing 120 tons of BP-1 lunar simulant. The geometry of the MEP is a cylindrical tube 0.071 m (inner diameter) × 1.2 m (length). The general methodology is to combine the data from instruments that measure different aspects of the particle size distribution. From a mathematical point of view, the dust measurement method described in this paper is nearly identical to the methods used by radar and hydro-meteorologists where a microwave radar, an accumulation rain gauge and a rainfall disdrometer correspond to the MEP laser side-scatter, total dust mass measurement, and fine particle analyzer (FPA).