Praise be to Allah, The Lord of universe. Only with His uncountable favors that I can finish this work. Wish He accept all of my faithful learning efforts as the way I sincerely express my gratefulness.
The credit belongs to my supervisor, Prof. Dr. -Ing Eko Supriyanto, for his advanced guidance in conducting research. Comments and suggestions from Prof. Dr. Andriyan Bayu Suksmono, Dr. Hau Yuan Wen, and Dr. Ir. Suprijanto helped me to improve this thesis. There has been supportive discussion about ultrasonic with Prof. Dr. Amoranto, and sensor configuration with Dr. Dedy, also abstract correction by Dr. Maheza. I should as well named Prof. Dr. Mohamed Khalil Hani who inspires me a lot, although I was only able to take the digital system lecture briefly. Special gratitude is dedicated to Dr. Muhammad Nadzir Marsono for his precious tips in electronic design and also for \LaTeX tutorial.
I would like to convey my thankfulness to Universiti Teknologi Malaysia (UTM), Multimedia Super Corridor (MSC) and Ministry of High Education (MOHE) Malaysia for supporting and funding this study. My appreciation goes to the Diagnostics Research Group (Biotechnology Research Alliance) affiliates for their ideas, helps, and very graceful surroundings at the laboratory.
To my family, and my beloved ones, the star, there is no word I could write which is adequate to depict how much they mean to me. The reason that has been keeping me going on through these times. My pray, “May Allah always protects your happiness.”
Lastly, here I have met many people who gave me invaluable lessons. Thanks to all: my house companion, PPI’s fellas, IKMI members -especially the teachers-, and other friends, for being part of my life’s experience.