Browsing by Author "Gebru, Alem Kindeya"

Now showing 1 - 1 of 1
  • Thumbnail Image
    Item
    Development of a kHz optical remote sensing system for in situ insect monitoring
    (Stellenbosch : Stellenbosch University, 2016-03) Gebru, Alem Kindeya; Rohwer, Erich G.; Neethling, Pieter N.; Sorensen, Mikkel B.; Stellenbosch University. Faculty of Science. Dept. of Physics. Laser Research Institute
    ENGLISH ABSTRACT : In this work we have developed a kHz optical remote sensing system for in situ insect monitoring applications. This is an active and passive remote sensing system based on laser and sunlight. This system showed potential for monitoring pollinators in agricultural fields. It enables the implementation of improved vector control mechanisms and pest management. The passive remote sensing setup called dark field spectroscopy uses sunlight as an illumination source. Considering the passive remote sensing techniques, it is shown that one can determine flight direction, retrieve spectral information, and resolve wing-beat frequency (and harmonics) and iridescence features of fast insect events. With regards to active remotes sensing technique, a number important range resolved quantitative assessments of insects such as size, speed and wing-beat frequency can be performed. It is shown that the CW-LIDAR based on the Scheimpflug principle improves the range resolution beyond the diffraction limit. The reason for this is because of the fact that the sampling frequency is in the order of kHz and insects behave like blinking particles similar to super resolution microscopy called stochastic optical reconstruction microscopy (STORM) where molecules blinks between bright and dark states. Generally, this dissertation highlights the potential of applied optical remote sensing techniques to remotely identify insects and understand their impact onan ecosystem.