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,
May 26 - May 31
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...
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
June 1 - June 5
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.
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
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.
June 8 - June12
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...
June 15 - June 19
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
June 22 - June 28
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.
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."
June 29 - July 5
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
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...
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.
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.
July 6 - July 12
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.
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!
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
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
July 13 - July 19
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.
July 20 - July 26
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
July 27 - August 2
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.
August 3 - August 7
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!
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
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.