Correlation of stage decay and moisture content of Mollucan sau (Albizia falcataria) with ultrasonic amplitude using PC- based ultrasonic technique
Date
4-2002
Degree
Bachelor of Science in Applied Physics
College
College of Arts and Sciences (CAS)
Adviser/Committee Chair
Emmanuel A Florido
Abstract
A PC-bases detection system using ultrasonic technique was designed and developed for determining the decay of Moluccan Sau (Albizia falcatria). Using the through-transmission instrument set-up, the correlation between ultrasonic wave amplitude to moisture content and weight loss due to decay of the wood was determined. The wave amplitude was measured using a peak-detector for faster collection of data. An ultrasonic piezoelectric sensor was used. A receiver and transmitter pair was configured with 25 KHz as the sending frequency of 6 V peak-to-peak ultrasonic waves. The waveform received was studied further using the Fast Fourier Transform of the signal to derive the power spectrum of the signal. A total of 80 samples were prepared. Thirty samples were used for inoculation of two different fungi, White-rot and the Brown-rot fungi. Only 47 samples were observed and tested. A moderate correlation of -0.54210 between amplitude and % weight loss due to decay was obtained with high level of significance (<0.0001) while a weak correlation of -0.23730 was obtained between amplitude and % moisture content in non-dry samples with no significance (0.1083). When the amplitude of non-dry samples were compared with oven-dried samples, a correlation was obtained with high level of significance (<0.0001). It is possible use ultrasonic techniques in determining stage decay of wood but it is recommend to use a large number of samples in calibrating the instrument .
Location
UPLB Main Library Special Collections Section (USCS)
Call Number
Thesis
Recommended Citation
Tapia, Alvin Karlo G., "Correlation of stage decay and moisture content of Mollucan sau (Albizia falcataria) with ultrasonic amplitude using PC- based ultrasonic technique" (2002). Undergraduate Theses. 10591.
https://www.ukdr.uplb.edu.ph/etd-undergrad/10591
Document Type
Thesis