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News Release

How UCSD changed my life and might change your life too: A Q&A with ECE alumnus Dan Chang

San Diego, Calif., June 10, 2019 -- A Q&A with ECE alumnus Dan Chang

Dan Chang (ECE department MS '68, PhD '70) attended UC San Diego at an interesting time in our history and had classes with many legendary names.  In the late 1970s, he was hired at Sandia National Laboratories. However, he did not know until after his arrival that he would be working in the weapons group.  As a Buddhist and a member of Amnesty International, he had mixed feelings.  He decided that if he was going to work in weapons he wanted to find an ethical way to participate.  Using his background in electromagnetic waves, he found that an accidental nuclear weapon launch was far more likely than previously thought, and that a lighting strike had the ability to accidentally fire an armed nuclear weapon.  His research led a movement to reduce our nuclear stockpile.  Additionally, in the 1980s, a radar tool he developed was recognized by both the United States and Soviet Union as a tool to confirm compliance to the Threshold Test Ban Treaty for underground nuclear testing.

Chang feels that he left the world a better place after his 30 years in industry and credits his time at UC San Diego with putting him on that path.  He is passionate about ensuring that our current engineering students know that they are capable of doing more than making a lot of money with their degree. 

Chang has established an endowed award in honor of his mentor Professor Henry Booker. The Henry Booker Award for Exemplary Engineering was created in honor of his Ph.D. mentor to encourage engineers to broaden their perspective and use their knowledge to make a positive impact on society. This comes with the faith and confidence in the Jacobs School of Engineering’s mission to continue to use engineering for the global good and the belief that an ethical and socially responsible person will be "rewarded with health and happiness."

How did you get to UC San Diego?

I came to the U.S. around Thanksgiving holiday in 1967. I wanted to attend the graduate school of University of Pennsylvania in the spring semester in January. I came one month earlier in order to learn some English.  University of Pennsylvania is an Ivy League school and was quite famous in my native country Taiwan. One thing I did not consider in choosing this school was its cold weather in the wintertime. It snowed most of December.  I was not able to go anywhere (I could not drive then) to practice my English. I stayed home every day babysitting my host family’s 5-years daughter and her English vocabulary was not any better than mine was. Taiwan’s weather is sub-tropical, so Pennsylvania’s weather was too much a contrast for me.

Fortunately, the day after Christmas, I received mail from my dad, attaching a letter from UCSD offering me a research assistantship. Actually, my dad received UCSD’s mail only a few days after I left Taiwan. At that time, airmail was very expensive, so he sent it by ship.  It took a month to get to me. I decided immediately that I wanted to go to San Diego for a better weather. I could not get any airline tickets because of poor weather, so I bought a train ticket.  It took almost two days to get to San Diego. A meal on the train costed around $10, which was my dad’s one-month salary in Taiwan at that time, so I decided not to eat any meals on the train.  Instead, I bought one big bag of apples and one big bag of oranges to the train as my meals to survive the next two days. To this day, I am unable to touch apples and oranges anymore because I had enough of them on that trip.

How did you wind up studying electromagnetic waves?

At that time, information science was a new field and was not sufficient to form its own department. My department at UCSD was called “Applied Physics and Information Science”.  I really wanted to study information science because it was a promising new field. Unfortunately, the professors in the information science were all young professors. They loved to use contemporary slang and I had a difficult time understanding them.  For example, if I asked them for a simple answer “yes or no” they would reply, “you bet”.  For someone like me just came to this country one month prior, I really didn’t know whether “you bet” was “yes” or “no”.  Only one older professor, Henry Booker would not use slang and I thought that I could understand him better. He offered a class called “Electromagnetic theory,” which was not particularly interesting to me. I decided to take his class to get by the first semester until my English was better. He asked for a term paper at the end of the semester. On the due date, I brought with me many blank papers because I thought he wanted to have an examination. I did not understand “term paper”.  Professor Booker was not pleased and he informed me that I needed to read a paper and write a report on it.  He granted me an extension to complete the term paper, but he only gave me two weeks to complete it.  If I did not have a term paper by then, he would gave me an “F”.  If I had received a failing grade, I would have lost my scholarship and would have to pack for home.

Since my English was very poor then, I felt that I needed at least one week to write the report and type it.  Therefore, I really had just one week to read a paper.  I was not able to read a long paper because it would have too many new vocabulary words that I had to check the dictionary constantly.  Fortunately, I was able to find a 2-page paper by Alfven, Hannes entitled "Existence of electromagnetic-hydrodynamic waves" and I wrote a term paper on this article.  I ended up receiving an A-.

How did you join Prof. Booker’s research group?

Prof. Booker was a host family of two Taiwanese students from another department. He heard from these two students that I was not very happy in the department because my advisor had too many graduate students and had no time to take care of me. He asked me one day whether I would switch to him as my advisor. I was overjoyed and said yes right away. Prof. Booker was the department chair then and my advisor at that time was his former student.  Therefore, there would be no bad feeling on this transition. In addition, he did not have other students as an advisor because he planned to retire in a few years. I did not need to compete with other students for his time.  I came from Taiwan and our culture there was not very aggressive. I would not have felt comfortable if I had to compete with other students.

Prof. Booker treated me exceedingly well.  I passed the qualifying examination and the final dissertation examination easily. I received my Master’s and Ph.D. in 3 and half years.  It was not until 1970 when I received my Ph.D. that my puzzle was resolved. Prof. Alfven received his Nobel Prize in Physics and became a faculty in my Department. Prof. Alfven’s main contribution was his 2-page article that I selected for my first term paper. I chose this article simply because it was only two pages long and I could finish in a week.  However, the professors in my department thought that I was very smart to pick an exceptional paper as a first year graduate student and was able to understand it to write a term paper.  That explained why Prof. Booker had gone out of his way to have me work under his tutelage.   Fig. 1 shows Prof. & Mrs. Booker at my graduation.


Fig. 1 Prof. & Mrs. Booker on Dan Chang's Ph.D. graduation

Anything more about how Prof. Booker helped you that you would like to tell us?

Professor Booker invited me to his house for dinner to teach me about American customs and culture, such as table manner of using folk and knife, and where to put the napkin etc.Back home, we had used chopsticks and handkerchiefs. He also explained that I need to give tips at restaurants and what the appropriate amount would be, because we did not give tips back home. In Asia, we usually call a person’s last name with Mr. or Mrs. to show respect. In this country, we general call a person’s first name. I learned these customs through Prof. Booker because he had many foreign students before and knew the cultural differences. These customs sounded so basic and ordinary, but were very helpful for me to mingle into mainstream society at earlier stage of my life in the U.S. One year after, I met my girlfriend Cecilia who became my wife 3 years after.Prof. Booker also invited Cecilia to his house for dinner.

I spent time with Mrs. Booker on weekends to practice my English.She would ask me what I did the week before. If I told her that I went grocery shopping, she would ask me what kind of meat and vegetable I bought, and how I cooked them to continue our conversation to practice my English. One time, Prof. Booker asked Cecilia whether she had a driver license.Cecilia said that she failed the driving test because she did not know how to do parallel parking. Prof. Booker spent one afternoon weekend to teach her parallel parking. She finally passed the driving test shortly after

One day, Cecilia and I asked Mrs. Booker how we could pay back since they had done so much for us.She simply told us to pass along the love that they had shown us on to other.We have spent our lives since trying to do just that.

Tell us more about your family?

I married Cecilia and we had two boys. I wanted my boys to be grounded and ordinary people. In Taiwanese one of our sons is called “ordinary” another is called ”people”. This is my personal secret. Our two sons are now grown up.  One is married to a medical doctor.  Another one married a university professor. My daughters-in-law loved ordinary people so that they can enjoy life.

What did you do after your PhD?

First, I was a postdoctoral researcher at the University of Colorado in Boulder.

After my post-doc, I sent out 200 resumes and got only one interview.  Fortunately, I was able to get a job at a small company in Albuquerque, New Mexico. This company was very friendly and had little politics.

One day, Sandia National Laboratories in Albuquerque planned to demonstrate their new solar energy technology. My wife and I were quite curious because it was 1978, so we joined the tour. At the end of the tour, the bus stopped in front of the Sandia’s personnel office around 4:30 pm.  My wife asked me to drop in the personnel office to see whether there were any job openings. I told the recruiter that my background was in electromagnetic waves. He scheduled an interview the next Wednesday and I got an offer on Friday. They did not tell me what I was supposed to do.  At that time, my company was in financial trouble and had just sold to a big company back East. I decided if I wanted to work for big company, I might as well work for Sandia. I accepted Sandia’s offer.

What work did you do at Sandia?

I was assigned to Sandia’s nuclear weapon group. They wanted to know the effect of electromagnetic wave generated by nuclear weapons and how to protect electronic systems from this effect.  I was not quite prepared and to work in weapon’s group and had several reservations.  I was a Buddhist at that time and found it difficult reconciling my career with my beliefs. This was also a time right after the Vietnam War, and many people were tired of war and the constant fear and paranoia of the Cold War, which was associated with nuclear weapons. I was also a member of Amnesty International, which had received the Nobel Peace Prize in 1977. Many of my colleagues from Amnesty International would lie on the street to stop trucks from carrying nuclear weapons to get into the air force base. Since I had already quitted my old job, I had decided to stay in this new job until I found a non-weapons department to work in.

What was your most important contribution during that time at Sandia?

To avoid bad actors from obtaining and firing a nuclear weapon, U.S. nuclear systems are unarmed until the President sends an authorized order. At that point, two people from two different organizations would need to enter security codes to activate a weapon. If the codes match, the system will be armed. For this reason, the system needs a connector to the outside world. This connector will automatically close during lightning strike so that a large electrical current from lightning will not go into the weapon system to cause a premature fire. This is a designed security measure.  The weapon designers claimed that the accidental rate was one in a million. As my background under Prof. Booker was in electromagnetic waves, I had decided to look into a situation when lightning did not strike the weapon directly. The connector will not be closed. Since lightning will generate a strong electromagnetic field and it has a very wide bandwidth, I found that the circuit inside the system would resonance at some frequencies and produce large currents to cause the system to fire prematurely. I was able to prove both theoretically and experimentally that the accidental rate was one in a thousand instead of one in a million. This study was done at 1979-1980.  Since an un-armed nuclear weapon concept was very important for nuclear security, an outside connector was essential. One way to reduce any pre-mature accident during the lightning was to reduce the stockpile.  A few years after my study, U.S. had decided to reduce its stockpile. Reduction would not happen overnight.  The government needed first to double check my study both theoretically and experimentally.   The production contracts usually were awarded a few years ahead. Closure of tactical nuclear weapon sites would take many years to complete. It would be many years before the actual reduction in the stockpile occurred. As shown in Fig. 2, global nuclear warheads reached a peak of 70,000 in 1985 and had since reduced down to around 15,000 today.

Fig. 2 Global nuclear stockpiles

You made another important contribution to denuclearization later on?

In 1980, following the outbreak of the Iran–Iraq War, world oil prices raised sharply. Sandia National Laboratories decided to work on energy research to increase oil production.  So, I told my boss in the weapons group that I would like to transfer to the energy group. He was very happy to see me go because I found a major problem in nuclear weapon in just two years.  If I stayed any longer, I might find more problems. At that time, seismic technology was used to detect oil fields. Its accuracy was very poor.  As it turned out, 9 out of 10 wells drilled for oil might be dry wells. So, I designed a radar tool to look around 100 feet range around these dry wells to see whether oil may be nearby. I had a theory that the oil fields are usually deep beneath the earth. But the earth crust has many fractures that will carry oil to an oil well. If we can find fractures nearby the dry well, we have a good chance to find oil. My radar tool provides very wide frequency spectrums so that radar can travel in different kind of soil.  If there is a fracture, a signal will be reflected back to the tool. From the time of arrival and direction, we could pinpoint the fracture. I had run many tests as shown in Fig. 3 to prove that this radar tool can detect fractures.

Fig. 3 Radar fracture mapping tool

In July 1974, the United States and Soviet Union signed a Threshold Test Ban Treaty (TTBT), prohibiting nuclear underground tests ( both countries had already stopped above ground nuclear tests ) of devices having a yield exceeding 150 kilotons (of TNT).  Unfortunately, the U.S. senate would not ratify this treaty because it was unable to verify the yield using any technology at that time. It was not until 1987 that Los Alamos National Laboratories proposed an on-site inspection technology called CORRTEX (Continuous Reflectometry for Radius Versus Time Experiment) to measure the electromagnetic radiation from the test site. Unfortunately, this technology alone was not sufficient due to lack of information about the real test site beneath the surface since the test site could be far away from the CORRTEX hole.

My radar tool was able to detect any discontinuity such as fractures in the soil and so was able to map the test site below the surface (Fig. 4) to provide accurate distance for CORRTEX.  We invited Soviet delegates to Nevada underground nuclear test site in Jan. 1988 and demonstrated our technologies. Finally, both countries agreed to use U.S. proposed on-site monitoring technologies to verify the yield from underground nuclear tests. With these new technologies, U.S. Senate finally ratified the TTBT treaty in 1990 by 98 vs. zero votes. The treaty became effective on December 11, 1990.  This treaty prohibited underground nuclear tests of devices having a yield exceeding 150 kilotons (of TNT). Since test results of any devices with yield, less than 150 kilotons (of TNT) were already well known to both countries. Both countries had finally decided to stop the underground nuclear tests: Soviet in 1991 and U.S. in 1992. This meant that the nuclear weapon technology would no longer advance. This was essentially the beginning of the end of cold war. It affected every one of us.

Our leaders decided the future of this country and the world.  Sometimes they need technological inputs to make a decision.  My study on possible accidents during lightning might provide our leaders an incentive to slowdown and eventually reduction of the nuclear stockpile. Further contribution on verification of the underground nuclear test might provide incentive for two major powers to stop underground tests. I hope that this is a better world today than it was 30 some years ago.  That is why I said that what you learn at UC San Diego might change your life too.

What was your greatest challenge as a student, and what advice do you have for current students who want to make the most out of their experience at UCSD?

When I was a student at UCSD, the Vietnam War was at a high point. Many colleges had demonstration against the war on campus. Since I was a foreign student, I did not have a danger of being drafted to serve in the military. I chose to participate in the demonstrations because I did not believe that humankind should kill each other to resolve their differences.One time, Police threatened to arrest us if we did not disperse by midnight. None of us moved.Fortunately, the UCSD chancellor came to sit in with us at midnight. The Police had finally decided not to take any action.If I was arrested, I would have been deported because I was not a US citizen. I would have lost my opportunity for advance study in this county. I chose to participate in the demonstration because it was the right thing to do in my mind. This was my greatest challenge that I had at UCSD. I was fortunate to be at a school that the chancellor loved his students so much that he was willing to sacrifice his own prestige. My advice to the current UCSD students is open up your vision on world affairs, not just your own small world. If we have a better world, our small world will be better too.

What advice would you give our current students or recent graduates interested in pursuing a career in your professional field?

In recent years, I have given many talks to university and high school students.At the end of my talk, I usually ask students the following question: In your future, if you have two choices in your life: 1. to become a billionaire.2. to reduce one nuclear bomb from this world.What would be your choice?

I did not ask students to give me an answer right away. Even if they gave me an answer, they can still change their minds in their long life after seeing how attractive money and power can do in their life. Fortunately, global nuclear bombs has now reduced to below 15,000. If my talk can influence 15,000 individuals to take action in reducing one nuclear bomb as their lifetime goal, we will have a better world. Sometimes technical background is essential in reducing stockpile, as in my case.


Media Contacts

Ioana Patringenaru
Jacobs School of Engineering