week[4]_termTestOmg

I just finished my term test and thank god that was an easy one. The whole test is pretty similar to the past test, especially the first question. However in the last 5 minutes of the test I found I misread the first question and all my answers are matched to the opposite situations. It was really a heart attack I tried my best to correct them all but since all this was in a hurry I realized that I probably messed up the quantifiers of the last two questions. Now I prey TAs won’t be so harsh on me, lol.

This week we are studying contradiction, existence and sequences. It is not hard as well since it’s all about prove a statement in different ways, but still some of them are quite “mind-wrecking”. Besides that I really like my instructor Larry and his lecture notes. Compared to the dull and plain course notes written by professors, Larry’s notes is really simple to understand and fun to read. These proofs and logic stuff are not only boring anymore with the memes, but also kind of pulling me to read and study it. If I really did well in this course, half is the time and work I spent on this course and another half is Larry’s interesting lecture and patient help :)

week[3]_a1

This week we have done our first assignment. This assignment is a bit harder than I expected, I started late but fortunately I finished it just in time and hopefully they are correct. For me, the most challenging part in this assignment is question 5, because I found these questions are really "flexible". You can think the question in a really complicated way, but they still make sense if you use a really simple method. This confuses me that it makes me not so sure which way should I use and which way is correct. Other than that I think it is pretty simple one.

Also, this is the fourth week which means 1/3 of our semester is gone, and so does the course contents. We finished the first part of the course, symbols quantifiers and logic statements, and two more parts are waiting which are proofs and algorithms. Proofs are easy too since the problems are not that hard as far as I see, all we need to do is write them in another way: the structured proof.  I hope I will be ok with that, and time to start reviewing our first term test.

week[2]_foldingQuestion

This week we studied conjunctions and disjunctions. This is pretty much union and interaction so this part is not that hard for me. The more interesting thing is, I see instructor posts folding problem on next week slide and I decide to talk about it here this week.

Here is what I got from the Wikipedia.

The napkin folding problem is a problem in geometry and the mathematics of paper folding that explores whether folding a square or a rectangular napkin can increase its perimeter.

The rule is one can consider sequential folding of all layers along a line. In this case it can be shown that the perimeter is always non-increasing under such folding, thus never exceeding 4

Robert J. Lang, who is an American physicist, devised two different solutions. Both involved sinking flaps and so were not necessarily rigidly foldable. The simplest was based on the origami bird base and gave a solution with a perimeter of about 4.12 compared to the original perimeter of 4. The second solution can be used to make a figure with a perimeter as large as desired. He divides the square into a large number of smaller squares and employs the 'sea urchin' type origami construction described in his 1990 book, Origami Sea Life. The crease pattern shown is the n = 5 case and can be used to produce a flat figure with 25 flaps, one for each of the large circles, and sinking is used to thin them. When very thin the 25 arms will give a 25 pointed star with a small center and a perimeter approaching N2/(N − 1). In the case of N = 5 this is about 6.25, and the total length goes up approximately as N.

week[1]_logics!

This week we are introduced symbols and quantifiers.

Symbols and quantifiers themselves are not difficult at all, I’ve seen them in my math books before especially the Vein diagram. However the tricky part is transfer daily language into logic statements and vice versa. For example, in our daily life we say “Go buy that headphone only if that headphone is half price off” but in logic we “say” Buy the phone -> Half price off.

Moreover I find the vacuous truth is more like a mind blow for me. For instance, if x^2<0, then x>x+5. In our daily life this is totally wrong and if we write it is correct in our math exam I would absolutely get a zero. However! However in logic, this is correct, isn’t that incredible? But after all that, when I get used to the logic language, I find it is fun to translate normal language to logic statements.

Besides I found an easier way to solve logic statement problems, which is simplify the question description and draw a Vein diagram about it, then everything is so clear and can’t wrong.

week[0] = "Hello world!"

Hello world! Probably this the simplest way to greet each other by computer scientists, or a super novice computer scientist.

I’ve written a slog for CSC148 last term so this is my second slog. As always, I would like to introduce myself a little bit, since there are not much actual contents in the lecture (lecture is doing introductions too!). I’m a second year student and I’m aiming to enroll computer science major program. I love computer games, I start playing games on console when I was 4 years old, then on computer a few years later. My favourite games at that time were SimCity 3000 and Red Alert. I really enjoy the game and for me it is a miracle that how computers can calculate the data, stimulate complex conditions and display fantastic images. This becomes one of my reasons to study in computer science when I graduate from high school.

Now I know that computer science is not only games but consist by lots of scientific fields, such as programming, designing, algorithms, hardware, arts design etc. My favourite part among here is art design, such as design character 3D models, that’s my dreaming job. However I believe do well in computer science will give me some outstanding background knowledge in computer science field, no matter what I’m going to do in the future.

And that’s pretty much about me. Good luck to me this term!