As I walked inside a room, I saw computers operating all day long and expensive-looking devices whose names I had never heard before. This was the first moment when I personally encountered cutting-edge technology and saw how seriously people study in graduate programs. At that time, three years ago, I was visiting my mentor, who is a researcher in a network laboratory in the Electronics and Telecommunications Research Institute (ETRI) in Korea. Full of curiosity, I was excited about such an environment that would lead me into an unknown world. Since then, I have seriously considered my future and made a decision to study further.
I am finishing a B.S. degree in electronic engineering at Soongsil University in February 2010 and applying for a Master's degree in electrical and computer engineering with the subdisciplines of communications and networking. The reason why I study them is because of two professors whom I admire the most; Dr. Young-Han Kim, my undergraduate advisor, and Dr. Yoan Shin. Dr. Kim encouraged me to keep questioning the principles and thinking about them critically. On the other hand, Dr. Shin helped me to understand abstract work easily and develop an interest in communication networks. Dr. Shin, especially, had the greatest impact on my decision to study abroad by introducing me to his positive personal experience of doing so.
The first step that I took to realize my dream was to study English in the U.S. However, my father did not let me go to the U.S.A. Nevertheless, I persistently tried to persuade him to allow me to study English in the United States and finally got the permission from him with a condition. The condition was to get GPA over 4.0/4.5. At that time, the middle of the semester, I was supposed to get perfect score in my final exams because I did not get enough grades in my mid-term exams. Otherwise, my studying English in the U.S. would be gone. I studied day and night and prayed to God for help. Unfortunately, my dream disappeared even though I studied very hard because my final GPA was 3.98/4.5.
One day, I had a chance to take a look my test paper because a professor allowed students to review their test papers whether or not there was something wrong. I did not expect anything about it, but I found something that an examination question was not graded. Immediately, I reported it and upgraded my score. As a result, my final GPA dramatically changed to 4.01/4.5. It was totally unbelievable and I was so happy because I felt that I got reward for my hard working.
Studying English in the United States, I did volunteer work in the Memorial Hermann Hospital Cancer Center at Texas Medical Center, Houston, Texas (noted in my resume) unlike other students. I did not want to spend my time on hanging out and drinking because it was so hard for me to come to the U.S. to study English and the time was invaluable to me. I wanted to do something productive and one of my friends, who is a nurse, recommended that I do volunteer work at the hospital. At first, volunteering was just a way to improve my English. After I started working at the cancer center and met people who were in the end of their lives, however, it changed me. I saw some patients hit golden bell which meant they overcame the cancer while others were gone with silence. I started taking a look around me. While I worked at the cancer center, I met a lady who was working as a volunteer for the Omega House, where people who have up to 6 months to live stay. One day, when she asked me if I was interested in volunteering at the Omega House, I could not say "yes". I was so confused. "What am I supposed to do?", "What can I possibly do at the Omega House where hope does not exist?" I kept asking myself. Volunteering was just one opportunity to speak English in public and I had never seriously thought about helping others wholeheartedly. However, it destroyed my arrogance thoroughly. I admit I was immature.
To be mature and strong, I read a lot and took a trip by myself. When I was on my way to across the United States from New York to Los Angeles by train, I kept thinking about who I am and what I am going to do. It took four days to get to Los Angeles from New York which was enough time to think about it. Finally, I decided that I would realize my dream to study further in the United States, the land of opportunity. Also, I set a goal to become a sponsor who supports others' education in 15 years.
To prepare for my professional and personal goals, I took seven courses and earned twenty-one credits related to communications and networking during my undergraduate studies. Those courses were Probability and Statistics, Signals and Systems, Data Communications, Computer Network, Digital Signal Processing, Analog Communication, and Digital Communication. I received all As in those courses. I was also top 1.25% student in the Digital Communication class. However, I took those courses not to get good grades in exams, but to fully understand their subject matters. Through those courses, I could learn not only professional knowledge as a prospective graduate student, but also skills as an engineer such as handling devices used in the laboratory and programming certain languages. As a result, I made a remarkable improvement in my grade from a 2.7/4.5 GPA freshman year to a 3.9/4.5 GPA junior year.
In my graduation thesis, I tried to utilize all the knowledge and skills that I have learned from undergraduate studies because I thought that those things would be a foundation for graduate studies and thus, I got to know how to maximize their utility. My graduation thesis is on wireless ad hoc networks. To be specific, the title is "Performance Analysis of Routing Metrics in OLSR using NS2." Executing simulations about Optimized Link State Routing Protocol (OLSR) with different types of routing metrics such as hop count, Expected Transmission Count (ETX), Minimum Loss (ML), and Expected Transmission Time (ETT), I measured bandwidth and end-to-end delay of the virtual networks and analyzed the performance of those routing metrics. Before the simulation, I hypothesized that "Quality-Aware" routing metrics, ETX, ML, and ETT, would perform better than the hop count, which is not supposed to be affected by the link quality. This is because routing without link sensing would cause serious network failure due to various link qualities and dynamic network topology in ad hoc networks. Through this simulation, I recognized that my hypothesis was right. Furthermore, among those "Quality-Aware" routing metrics, it turned out that ETT performed well compared to any other routing metrics.
In conclusion, my curiosity toward an unknown world led me to decide to continue my studies, and my mentors, including my professors, positively influenced my decision to study abroad. To be a professional graduate student, I have tried to be qualified for the position. I think the University of Illinois at Urbana-Champaign is the place that would best fulfill my intellectual interest. If I have a chance to attend your graduate program, I would like to work with Dr. Bruce Hajek and Dr. Andrew C. Singer. I am particularly interested in researching wireless ad hoc networks and Orthogonal Frequency Division Multiplexing (OFDM). My final destination, though I am currently applying for a Master's degree, is to be a professor who can inspire students to aim for a higher goal and achieve it, as Dr. Kim and Dr. Shin did for me.