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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Vliv retardace hlíz brambor na výskyt skládkových chorob / The influence retard potato tubers and occurrence storage disease

KLIČKA, Vladislav January 2008 (has links)
Influence of sprout suppression based on CIPC by fogging and amount of storage losses of chips potatoes, with target in losses caused by storage diseases were investigated at temperature 8°C storage. In experiment with varieties Saturna and Pirol higher quantity of storage diseases by Pirol against control were occured after one application of CIPC, Saturna held more storage diseases in control. Identical differences by necessary losses were observed. In another experiment with varieties Saturna and Merlin no differences in amount of storage diseases were registered at double, single or none treatment, neither in quantity of necessary losses. Losses by sprouting were various according to amount of applications of CIPC and duration of storage period.
2

Design and Development of a Low-cost Acoustic Device to Detect Pest Infestation in Stored Maize

Kiobia, Denis Olgen 17 September 2015 (has links)
Insect damage in stored maize is one of the major post-harvest losses occurring in developing countries, especially in sub-Saharan Africa. To reduce economic losses, separation of infested grains from clean ones is critical and requires detection of infestation in stored grains. This study aimed at developing a rapid non-destructive detection system with three goals; - the first goal was to investigate the acoustic behavior of internally feeding S. zeamais (Coleoptera: Curculionidae) in maize. The pests were monitored for peak activity and signal amplitudes. The study was performed in the morning, afternoon and night times for three consecutive days with an ultrasonic probe attached to acoustic emission detector. The average number of peaks above threshold in the morning, afternoon and night was significantly different and were 60, 2 and 31 counts/s, respectively (P-value < 0.01). The average maximum amplitude was also different: 2.5, 1 and 1.8V for morning, afternoon and night sessions, respectively. The signal frequencies ranged between 1 and 15 kHz with a peak around 7 kHz. The second goal was to design and develop an inexpensive acoustic device for the detection of S. zeamais in the stored maize. This device included a microphone, signal conditioning circuit and a microcontroller. The third goal was to test the prototype in both clean and infested maize. The device could be manufactured for $55 or less. The device has a noise level below 0.2V in clean maize, infestation amplitude up to 1V and about 93.3% correct detection performance in infected maize. / Master of Science

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