Weekly Journal

From the window of my plane, I could see that several pieces of lakes were mounted in the woods which covered everywhere. It seems that a lot of mirror islands located in the green ocean. Neat streets crossed the green, which looks like white strips. Immediately, I fell in love with this city, the city of trees and water, Providence, Rhode Island.

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Before my Work
May 26 - May 31

I arrived at Providence on May 26th. It's a nice and sunny day. After I settled down, my roommate showed me the campus of Brown University. On the next day, I briefly visited the area around the campus. It's such a long walk. I hope I could bring my bike...

I met Prof. Jennifer Dworak on Friday (29th). I couldn't believe she was so young. She showed the whole lab to me and introduced me to everybody. Porf. Dworak had two PHD student, Yiwen and Elif. Both of them became mostly helpful when Professor was out in the later time. After helped me set up a temporary account, she began to explain her three main projects. I also got my first homework at Providence, two papers in error detection during normal circuit operation and a C++ book, "Teaching Yourself C++ in 21 Days".

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Week 1
June 1 - June 5

Before working on the project, my work was reading papers and reviewing the related knowledge. By taking advantage of the last weekend I finished one of the papers. Both of the papers were related with the digital logical design, which was a course of my freshmen year. Haven't touched those stuff for about two years, a lot of knowledge seems very strange to me. So as to the C++ and C, I regretted to say,"I haven't touched it for half a year." I didn't know what's going to happen if I stuck on the debugging forever when I was working on a project. For me, of course, I didn't expect a more tough vocation than my school year...

But soon, I found I was just scaring myself in the past a few days. Nothing was that hard. I became familiar the programming language and found my lost memory very soon. On Wednesday, I began my first project. Exactly speaking, I began to help Elif edit a site dictionary for 4 circuits of her final paper by Fastscan software and C program. Her paper would due on June 15th. All my work was to finish my task as soon as possible, since Elif still need some time to analyze my huge amount of data. As far as I knew, the site dictionary of the first circuit, "fm_reciever" would have more than 50000 pins.

According to our verification, Fastcan was a super stupid software if you wanted to build a site dictionary for a designed circuit. That means a lot of function need to be done by writing C code. That's a challenge to my lost memory again, since I haven't touched C code for about 2 years... There's no doubt that a book named "Teaching Yourself C in 21 Days" came to me. However, I definitely didn't have 21 days to read this book, since the paper had to be submitted in 12 days.
"21 --> 12"---- seems A Tough Work....

In fact, C has the same computer language concept with C++. Then, I got familiar with C very soon. At the beginning, I successfully built a site dictionary for a 16 rows site dictionary. However, when I tried to build "fm_reciever"'s dictionary, new problems came to me. I had to delete the the unnecessary pins and sort them before ran the Fastscan. Otherwise, errors would be reported by this stupid software. In this case, a lot C code need to be written. Gradually, I became interested in the C programming language. Up to Friday, I almost done all the C code for building site dictionaries with any number of rows.

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Week 2
June 8 - June12

This week, I went on working with Elif's project. Since all the C code had been down, the rest things seems easy to do. However, when I ran the Fastscan on Monday, it always reported failure for some pins. Later, we found that not only the pins of flip-flops but also the pins of buffers with connected with the "reset" pins could not be reported faults when built the fault list. So, all I need to do was to delete all these unnecessary pins. Obviously, this is a stupid work without any technique required. However, the circuit's structure were very different with each other. For a circuit which have more than 5000 faults, this would be such a tough work. Luckily, those faults are not as much as I expected. With the help of "Find..." tool of .txt file, I picked out all the unnecessary faults from the fault lists. On Thursday, I finished all these three site dictionaries.

Elif was very happy about it. She then asked me to help her build the site dictionary of another three circuits. And then my new work began on Friday...

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Week 3
June 15 - June 19

I started my new work this week and I was introduced a new program, "gulf". Basically, "gulf" has the similar function with Fastscan, but for the new project, gulf would be more effective. My new work was to find the probabilities of the hard detected fault of c432 circuit on real patterns. Firstly, I need to build a test set for c432 through gulf, which was a list of patterns. These patterns would make each fault detected by at least 15 times. And then, a stuck at fault dictionary based on the test set was built by gulf. In this dictionary, every fault would be detected by at least 15 times. Faults which were detected exactly by 15 times were called "hard detected faults". My purpose was to find "hard detected faults" out of the stuck at fault dictionary. This time Prof. Dworak gave me her C code source file, then I just need to give some modification rather than wrote everything myself. I soon found all 56 hard detected faults with their patterns. After that, I found the common bits of the 15 patterns for every hard detected fault, and made the other uncommon bits as 'x's. This was called the template of the hard detected fault. And then, I made 1000 new patterns from a template by exchanging all 'x' bits randomly with "0" and "1".56 hard detected faults gave me 56 templates, which made me 56000 new patterns. A huge new test set with these 56000 new patterns was ran on all the faults of c432 through "gulf". Then I picked up the hard detected faults and found the detected number. This number divided 1000 would be the probability of detection for each hard detected fault. This project sounds complicated, but actually it's much easier than the last project. I finished it at the end of the third week.

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Week 4
June 22 - June 28

This week Jennifer, another undergraduate research assistant from Brown, and I continued to study the circuit c432. We had 3 parts analysis. I was responsible for the second part analysis. In my part, I need to generated a templates list with all the templates, and repeated each of the template N*(1/Ptemplate) times. After that, I got a long test set. Then, Fault simulation through gulf for all faults and I need to see how many faults missed. N would be varied until I found the lowest N with none of the faults missed, and I would find the number of fault's detection. With Prof.'s suggestion, I tried the value of N from 3 to lower. I got the lowest N 1.5, which was a perfect number for this analysis. On Friday, after I reported my results to professor, my new task came. I would study a new circuit c499 with the similar steps of week 3 and week 4.

I finished my work at early on Friday, since I planned to find Walmart myself with the information from google, of course also the bus schedule. I walked together with Jom, an uprising senior student of Brown University. "How will you go there?" he asked. "By bus and probably some walk." I answered unconfidently, because I definitely knew that I probably would walk for most of my journey, since I hadn't found the bus station yet. "Why don't you come with me tomorrow?" He asked. "Well, that's a wonderful idea!" I was very excited by his offer and very happy to get such a native guide. So I changed my plan a little bit and went to the Providence's public library with him in that afternoon. Although it's not a big place, you could almost get whatever you want, because the books or recordings you required would be sent from other places as soon as possible. Jom returned a bag of books, and got another bag of books back to home on that day. I felt ashamed about myself. Buying books has always been a "good" excuse for me to spend a lot of money. However, I seldom fulfilled my promise that finishing reading all the books I bought. "It seems that Rochester also have a public library..." I thought on my way home.

On Saturday morning, Jom and I met int front of the Starbucks at noon. I just found it's free to take buses in Providence by a Brown ID card. We got the Kennedy plaza, the transportation center, the center of Providence as well. I was amazed by the beauty of this New England city. The government house just like a mini white house. The building of Bank of America towered up into clouds. Goddess of Justice sat in front of the court, nobly and royally. Apartment buildings located orderly by the water and lawn. Some parts made me think about NYC; some parts reminded me Shanghai; some parts exactly had the figure of Beijing. However, none of them broke the beauty of a delicate small city. After we came back, it had already got the evening. When I lied on my bed, I thought "Next week, I will find the sea."

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Week 5
June 29 - July 5

This week was a fantastic week. In the lab, I continued to study c499 circuit. This time, I ran into some setbacks, but I solved all the problems successfully eventually. Full details were in my progress report, because I would like to save more space for my tourism this time.

Downtown
This Friday was the day before the independent day. Barus&Holley, the building of science and engineering, was closed. However, I still succeed to go to the lab by following a Professor. My work was done by 4:30pm. Coming out of Barus&Holley, I walked towards the downtown. I always loved to find somewhere I interested in. Last Saturday, when the bus overshot the buildings, rivers, streets and the figures of NYC, Shanghai and even my hometown, I had decided to visit them one by one by myself. On my way down the college hill, I met the Rhode Island School of Design(RISD). I had walked around some buildings of RISD a few weeks ago, but never found its huge scale until this Friday. Actually, it was even bigger than what I saw on Friday, since I hadn't found its huge library in downtown until the next day. I had thought UR's Eastman School of Music (ESM), a top music school in US, had already been in a huge scale as a school of art. However, RISD almost was twice as large as ESM. Under the trees, some students held their portfolio, sketching the nature around them; some of the others, stood in front of their easels, lost in meditation. I was also buried into this artistic atmosphere. Being an artist was my dream when I was a kid. However, I became an electrical engineer afterwards. Standing in front of the museum of RISD, I thought, if I had been admitted by a college in Providence by chance, I wasn't sure I wouldn't study art at RISD. After I passed the court, I saw the providence river. Kennedy Plaza, the center of downtown, was just on the other side. I walked along the river, until I reached the end. The calm water just like a mirror reflected the tall tower-shiped apartment buildings. I began to homesick at that moment, because I also lived in a tall tower-shiped apartment building by a similar river in my hometown. I could always see the image of buildings in the calm water from my window...

Water Fire
Providence was famous for its water fire. Every important days and almost every other Saturday, people could enjoy the water fire. Water fire was reputed as "the most popular work of art created in the capital city's 371-year history" and as the "crown jewel of the Providence renaissance". This Saturday was also the independent day, one of the most important festival in America. I guessed the water fire on this Saturday night must be extraordinarily exciting. At 8:00pm, I arrived the providence river. I didn't expect that there were such many people in Providence. Yesterday, on the same bridge, I could only hardly see a person, but today, I could only see people's hair! Dinning cars and people covered everywhere of the streets. Performers boated in the river and put the dried firewood on the shelve which were standing upon the water. Dark night didn't approach until 9:00pm. With people's cheer, wood was fired. Performers began to played fire in the water. Well, I guessed they were with the help of solid alcohol...At about 10:30pm, I don't remember the exact time actually. Fireworks displayed in the sky. All kinds of colorful light and the fire in the water built the most charming night for Providence.

Newport Cliff Walk
Remember? Last week, I swore that I would find the sea this week. I made this come true on Sunday. I arrived Kennedy Plaza Transportation Center at 12:50pm and just caught up with the bus to the Newport. After an hour, fishy smell had floated into our bus, although I could only see rows of white houses on both sides of the road. I believed the sea was at the back of these houses. I saw the sails behind the houses very soon. After a while, the bus ran onto a huge bridge. And, I saw THE SEA! All kinds of ships, sails and yachts shuttled in the water, peacefully and leisurely. After about half an hour, the bus got the destination, Newport Gateway. I changed to another bus and arrived the end of cliff walk at 2:50pm. The Cliff Walk along the eastern shore of Newport, RI is world famous as a public access walk that combines the natural beauty of the Newport shoreline with the architectural history of Newport's gilded age. When I came into the narrow road with the weed heavily growing, I was obsessed by the blue ocean. I climbed on a reef to feel the smell of the sea. This was the first time I faced the Atlantic Ocean, broad and boundless. I imagined at the other side of the ocean, I saw Britain, the only big country I hadn't set foot on in Europe. I continued my trip and enjoyed the scenery of the sea on my right side, and also the pretty mansions on my left side. Soon, I decided to walk up to the start of the cliff walk. I finished the entire 3.5 miles at 4:01pm. After back to the Newport Gateway bus station by bus, I began to walk around on the historical streets. All of the houses on these streets had more than 250 years history. However, they weren't as classical as the mansions by the cliff walk. These streets were too quiet. Soon, I felt some hustle and bustle. On the cross of the street, an very interesting phenomenon caused my attention. On a same historical street, from the cross to the west, I could only find the quiet trees and some old houses. However, from the cross to the east, I found crowds of people and a lot of shops with colorful banners decorated . I walked along the street and enjoyed the old history of this town. I thought if there's no people, the long history could only be some still objects; with people, the history became a lively story.

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Week 6
July 6 - July 12

This week, I continued working on the project of c499. With the instruction of Prof., after I got the 15 detected patterns of each fault, I exchange every bit to 'x' linearly, and got a very large group of patterns with only one x bit in every pattern. I did this for all 176 hard detected fault's 15 patterns and created a huge testsets with 176 group of patterns. I ran the huge new testsets on c499 through gulf. And then I would know which patterns in the testsets could detect their fault.
I left these patterns and combined them to a new pattern list. In this list, every group of patterns could detect their fault with a 100% probability. In this progress, I ran into several problems again. With the help of professor and the book, I fixed them before Friday.

On this Friday, I visited a Chinese friend's house. He had already been an employee of a electronic company. Since his wife was graduated in a same school as mine in China, I was invited to take part in his "Warming House BBQ Party" on Friday night. At that night, I got to known a lot of new friends. They invited me for deep sea fishing at Galilee on the next day. Sounds great for me!

Galilee Deep Sea Fishing
We started off at 6:30 in the morning. A coat was wore to protect me from the sea breeze. We got there by 7:45am, and ferry left at 8:00am. For my first sea fishing, I was supper excited. The ferry had the radar to probe the position of fish stock. After half an hour, our ferry stopped drive. People put the bait into the water and began to release the fishing line. I hold the fishing rod, waiting there. However, there wasn't a tiny move on my rod, nor the line. After a while, the ferry started, I raised my fishing line with a pity. However, I found the hook more and more heavy. It turned out to be a flounder!!! But the staff told me this flounder was still a baby and I had to throw it back to the sea. According to the law, people could only take the fish which was more than 21 inches. Even though I couldn't take it, I was still very excited, since it's the first fish I got by myself from the sea in my life.

It seems that I had a wonderful luck on that day. After my first fish, I got two more flounders, and one had 23 inches! Later, I got a big batfish which had 28 inches long. These two fish became the only two big fish that we took from the ferry on that day. Although we had 8 people, we only brought 3 fish to home. Two big ones were mine; the other small one was got by my friend Xia. In the evening, we went to a friend's house to cook the fish. It's my first time to eat flounder. It tasted really wonderful.

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Week 7
July 13 - July 19

This week, with my work on c499 and discussion with Professor Dworak, the goal became more clear to me. I was about to differentiate the observation bits from the excitation bits in those patterns who could detect the hard faults. For this, I need to know the site name of each fault. That meant I had to come back to Fastscan program. Since I had just analyzed c432 with Fastscan two weeks ago, I wouldn't have so much trouble on running this again. However, things did not always be as you wishes. Both my computer and my account were done on Thursday. And the staff told me it's such a serious problem that I had to reinstall the computer again. However, he would be free until next Monday! Well, I was forced to have a rest on Friday. :)

On Saturday, I went to RISD Museum of Art for a Design and Architecture exhibition of the architect Marcel Breuer. I was impressed by his work. I couldn't find any flaw out of the models of architecture from any point of views. Even the design and decoration inside were just perfect to form a unified whole. I walked around those models, and I found it a incredible artistic shape from every angle. Later, when I stepped into the European exhibition rooms, I found the grace of classic. They were pretty, I admitted. But I have to say they looks out of this fashion.

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Week 8
July 20 - July 26

Computer was back to me on this Monday. I continued my work of picking out the observation/excitation bits from patterns of the circuit c499. Since I had made some preperation in last weekend, my work proccessed with out a hitch. On Wednesday, I had get the observation/excitation patterns which were combined by the observation/excitation bits repectively. However, the result were not the one as expected. In my excitation pattern list, some of the patterns included only 'x' bits. Although this was not impossible at all, it was still really odd. So, with Prof. Dworak's suggestion, I did the same thing for the circuit c432 to see how the c432's excitation/observation patterns looked like. As a combination circuit, c432 was more ordinary than c499, so we supposed we could get a reasonable result from c432. However, the result of c432 was more bizzaro than c499's. It turned out to be that some observation patterns included only 'x' bits, which proved that there must be some mistakes in my procedures. Observation patterns with all 'x' bits meant that this pattern's corresponding hard fault could be detected by any patterns, which was impossible. I began to check my precedures very carefully. On Friday, I found a huge mistake that I had chosen wrong fault numbers for the other faults which share the same sites with the hard faults. I was very remosed, since I knew that any tiny mistakes in procedures were unforgivable. To me, it just a wrong result for a project, but what if it's an a lot of people's huge task? However, Prof. Dworak not only pardoned my mistake but also gave me a great comfort. "Well Nan, mistakes were very usual. The important thing was you found them out from the odd results. That's much better than that sometimes people enjoyed their looked reasonable results, which came from the wrong precedures..." One thing, she was right. "I found the mistake out myself." Perhaps, it could be a good lesson to keep me more careful.

This weekend, I went to Newport again with my friend Rick. This time, I mainly visited the mansions on the beach. Those mansions were built before the last century. Some of them patterned from the classical palaces of Europe, grand and splendid. Some others were typical west European villas, charming and graceful. I got a ticket for 2 mansions. We came into the Breakers, the biggest and the most grand one. Bright French casements, grand main hall, elegang bedrooms... I almost lost myself in these beauties. When we came out, it had been 5:10pm. The other mansions had already closed, but I still had one mansion ticket left on my hand. Rick said, "See, god ask you to come back in the future."

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Week 9
July 27 - August 2

Professor was on a conference this week. Yiwen and Elif were out of town too. I really need to figure everything out by myself this time. After I found my first procedure mistake last week, I still didn't get a reasonable result. This deadloak was not broken until Yiwen came back to the lab on Thursday. I had a big misunderstanding on the output patterns. Every time, when I changed one bit of an input pattern, its corresponding output pattern changed at the same time. To find this new output pattern, I had to simulate the good circuit through fastscan. This was such a important information that helped me get the reasonable result eventually and also played an important role in my next project.

Providence was only 1 hour away from Boston. There was the commuter rail between these 2 cities. On this Saturday, I went to Boston by commuter rail, and this was my first time to travel by train in US. I arrived at Boston at 12:30pm. After I got a system map from the information service, I began my independent travel. Compared to Providence, Boston was a big city. It was more flourishing and crowded, and had more skyscrapers. Especially, when I looked out the city from the ferry driving in the sea, office buildings, commercial buildings and apartment buildings crowded on the shore. It looked like hundreds of different kinds of flowers in clusters on the ground. But it also exposed Boston's weakness, "messy". Perhaps, this word was too much. New York was also full of skyscrapers, but all the builings lined up orderly; streets and roads paralleled with each other. If you had a good sense of direction, you could easily find out where you were in New York. But in Boston, if you did not have a map, you would get lost easily. On that day, I visited a lot of places. I had walked all the places covered by the freedom trail, which was almost the entire downtown. I came to Harvard in the evening, and was amazed by its scale, its dignified schools and its solemn atmosphere. I felt humility at once. I came back to Providence at 9:10pm. After I stepped out of the train station, I felt that I still loved Providence's elegence and delicacy much better.

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Week 10
August 3 - August 7

This was my last week and also a tough week at Brown. Professor came back on last Saturday. She and I and Yiwen had a meeting on Sunday. We talked about my result and a new task came to me. My last project was to find out all the excitation and observation bits from the patterns of hard faults. The excitation/observation patterns were obtained by repectively congregating their excitation/observation bits with 'x' bits. In this project, each bit was considered independently. However, this might miss some excitation/observation patterns. Because some bits might be required for both excitation/observation. In addition, in some cases, the excitation/oberservation requirements might be satisfied by alternative bit assignments. So my work of the last week was finding a more precise excitation/observation pattern list. This new project still mainly dealed with the C program and Fastscan. The only difference was I need to write two large C program for each circuit. This program would help me do everything, including evoke fastscan for several times when it ran. This week, Yiwen flied back to home; Elif was busy with her test preparation. Fortunately, Professor was around everyday. At Friday night, I succesfully finished all my work. It was almost the last minute of the 10 weeks!

At these 10 weeks, I learned a lot of things, C and C++ program language, fastscan software and so on. I appreciated all the help I got from everybody. I thought the most important thing I got was the method and process of doing a research, and also the happiness from my success.

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On the next Monday morning, I left Providence. I looked out from the window of my plane. I saw that several pieces of lakes mounting into the green. Neat streets went around the rows of little houses. I hope I could come back again.