projects done in 2010
projects done in 2009
Senior engineering projects done in 2008
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Maturity Detector of Fruits by using Knock Sound Processing "
Project Team: Peerapong Somboonyod, Theerapon Paritwanon, and Warunee
Problem: Thailand is the land of agricultural products in
which the quality of fruit is importance for product grading. In
2006, Thailand can export agricultural products about 155,000 Tons
or about 3.2 Billion Baht. Since the knocking method is a
traditional knowledge of Thai people for long time, this method can
be able to check whether the fruit is maturity or immaturity.
However, this method requires more experiences and only experts can
Basic Idea: This project proposes a simple nondestructive
method for determining maturity of fruits by using knock-sound
processing. The basic idea of the proposed method is on the basis of
a force and a position of knocking can be set. Based on this
assumption, we can design automatic machine for knocking and
recording the knock sound. The knocked sound will be analyzed
based on the signal processing techniques.
Working process of the proposed method
Prototype of automatic knocking machine
Method: The designed knocking
machine consists of a bidirectional DC motor 8.33 A, H-bridge
circuit, microcontroller PIC18F4550, and movable knock-arm connected with
the DC motor by a machine belt. Microcontroller is used as a central
control unit to control angular velocity and direction of knock-arm.
During experiment, a sound of knocking was recorded through the
condenser microphone which to be considered as an impulse response
of fruit. To process such sound of knocking, the recorded sound was
converted to the digitized signal at sampling rate of 44,100 Hz with
16-bit resolution and a total length of whole sampling 4,096 points.
The sampled data will be processed as a small segment or called
windowing technique. To determine the rate of change, we proposed
128-point windowing technique with computation of standard deviation
(SD) value. This process is repeated over total length of data
therefore we then obtain 32 points per a time of knocking. We can
specific threshold value between maturity and immaturity of fruit by
applying probability density function of the distribution of SD
FDM Software Version 1.0 used as a knock sound processor
Experimental Results: In the experiment, 10 pineapples and 10 durians (of “Monthong” variety)
to be tested for showing the effectiveness of the proposed method. The proposed method can be
able to classify the maturity of fruits by the average rates of
95.5% for pineapples, 85.0% for the weight of durian
3.5-4.0 kg. and 88.7% for the weight of durian 4.0-4.5 kg.
Publication: T. Paritwanon, P. Somboonyod, W. Bundit, and M. Phothisonothai,
"Non-Destructive Fruit Maturity Determination by using Knock Sound
Processing" The 10th Annual Conference of Thai Society of
Agricultural Engineering on Innovations in Agricultural, Food and
Renewable Energy Productions for Mankind (TSAE2009), pp.344-349, April 2009.
" Development of
Computer Software for Pathological Analyzing of Thai Language Learners "
Project Team: Nalinee Chanamool and Benyada Unhalekajit
Problem: Since Thai tone is unique comparing with other
languages because the different part of consonant phonemes from the
vowel. It plays key role in pronouncing Thai language especially in
the specific tones, segmentation of each consonant phoneme from the
vowel is required for analyzing Thai speech signal. The problem of
Thai pronunciation has been recognized as the nation issue and there
was the Thai Language Clinic for Youth.
overview of the phonetic analyzing method
example of specific tone segmentation using the proposed method
Basic Idea: This project proposes the development of computer
software for phonetic analyzing based on the speech processing
techniques. We named this project as the "PATHAI (Phonetic
Analyzer for THAI language learners)" software. The PATHAI software
supports not only Thai
speakers but also foreigners as well, they can be able to practice themselves the
pronunciation of specific Thai words.
plot the values of two parameters
Method: There are three main processes of the proposed method;
1) preprocessing, 2) feature extraction and 3) classification. This
project selected two parameters that are zero-crossing rate (ZCR) and time
duration (TD) of phonemes for creating the template database. The speech signal of correct pronouncing is
recorded, and then ZCR and TD of each word will be categorized
as the templates.
Software Version 1.0 (developed by using Delphi language)
Analyzing the recorded speech by PATHAI
Experimental Results: The 5 females (aged 20 - 25 years) and 5
males (aged 20 - 25 years) volunteered to participate in
this experiment. The results show that the method can archive the
accuracy rates of 61.1% - 90.0% approximately.
N. Chanamool, B. Unhalekajit, and M. Phothisonothai,
"Development of Computer Software for Phonetic Analyzing of Thai
Language Speakers" The National Computer Science and Engineering
Conference (NCSEC2009), pp.445-450, Bangkok, Thailand, 2009.