Semester in review, and what I did this summer

The classes I took this Spring semester were:

Materials Processing-- The manufacture and modification of the most important engineering materials: metals, plastics, ceramics, and composite materials. Topics covered included casting, forging and other shaping processes, welding (there's a whole lot to it; you'd be surprised) and other joining processes, machining, and a bunch of other stuff. It was a pretty tough class. I pulled several grueling all-nighters for it. I thought I was going to end up with a C but I got a A- somehow. It was the first A- I was extremely happy to receive. I will spare you pictures of my quizzes and assignments-- I trust you will take my word when I say it was hard.

The most interesting thing I learned in that class is that the idea that glass is NOT a "slow moving liquid" that deforms over decades. People made the induction from old houses having deformed windows and spread the commonly-held misconception that it had done so over many years. In fact, older glassmaking techniques had no way of ensuring consistency and flatness of produced glass; if a thicker end resulted, they would just use common sense and install that end at the bottom so it was less prone to breaking.

Materials Processing Lab-- Deformation of metals and plastics, like shearing, bending, upsetting (in layman's terms, "squishing") and wire-drawing. We would look at the microstructure of the deformed metal most of the time. There was a lot more to it than what I just described, but that's probably all you want to know.

This is what martensite looks like on a microscopic scale. Martensite is formed by quenching mid-to-high carbon steel from a high temperature. It is very strong (in terms of elasticity) but very brittle. For this reason, not all steels are "weldable" because high-carbon steels can form martensite at the weld as it cools and make the weld prone to failure, which is a very bad thing.

Mechatronics-- This class was a mess. It was a crash course in Electrical Engineering. We had 2 quizzes per week (one for reading comprehension, one for homework comprehension) and the tests were hit-or-miss. I made a (on an objective grading scale) failing grade on one, and a 95 on another. The final was a very anticlimactic one-- it was just another test. Off the top of my head, major topics covered were basic DC circuits, power engineering, signal analysis, transistors, op-amps, AC circuits, magnetism and magnetic circuits, and motors (there are about a dozen or so different types of electric motors, and they're all complicated to even understand how they work).

 This is an animation of how a 5-5-5 timer operates. It's a cheap, "simple" chip that has an only function of toggling on and off by itself. I still could never make sense of how it actually works.

Mechatronics Lab-- The most ridiculous lab I've ever taken (and probably will take) in my college career. The way it was administrated was very... unique. I've had labs in the past with very time-consuming and painful-to-write lab reports, but there were no reports in this lab. Instead, most of the work went into prelab assignments, which, in every other lab class, are not so bad. But these regularly took many hours to complete, even with the help of a friend.The lab section itself was more of an intelligence test than anything. So many things could go wrong with building your circuit, and for me and many others, they almost always did. Murphy's Law was blatantly obvious in that lab. Circuits are confusing, and there is no way to prepare for it. There was no way to practice; you just had to think quick on your feet. I made a previous post about this class.

Engineering Statistics-- At first, this class was pretty neat. It was my first introduction to probability theory and it was interesting stuff. However, as the class progressed, the material progressively became more difficult, abstract, and boring. Thankfully, I had a great TA, and his discussion sections were much better than the seasoned professor's lectures. The tests were ridiculous-- they were split up into two separate tests. One was quantitative problem solving during the discussion section, and the other was pure theory, in the form of essays, during class time. There were EIGHT essays per test. Luckily, I was exempt from the final (receiving the good news was probably the happiest moment of my semester), which turned out to have SIXTEEN essay questions to be answered over the course of 3 hours. I was saved from that painful experience, and not to mention the task of studying for it.

Confidence intervals and null hypothesis error.

Machine Elements-- This course was pretty eye-opening as far as structural design is concerned. We covered failure and fatigue of metal of structural components of machines, and we looked at many important elements like shafts, bearings, gears, springs, and bolts. Each and every one of them are much more complicated than you'd think, and it really made me appreciate how much consideration goes into what seems like the simplest of things.

Planetary gears are pretty crazy. And hard to analyze.

I also took a machining certification class near the end of the semester. I learned how to run a bandsaw, mill, and lathe.

This summer, I worked ~20 hours a week doing "research" here at UT, but it's more of a design project than anything else. It's called research because it's such a creative, open-ended process. I, another student, and my Machine Elements professor are designing a da Vinci-inspired walking lion which must also be able to turn and sit, that is almost purely mechanical (no robotics) for a guy called Shaun Whitehead and a French company called Dassault Systemes, to showcase their Catia software. It will probably end up in a French museum when they build the actual product from our design. However, the design is not such a straightfoward process. It's challenging to say the least, but I like the job even though it's not easy. I'd much rather do a mentally demanding job than a physically mandating job, or a repetitive job of either kind.

Here's what we have to show so far:

Digital Logic Circuits

One of the classes I'm taking this semester is called Mechatronics. The area of study is becoming extremely common in modern technology; an easy example of this is robotics. In fact, I just recently signed up for a robotics class in my last semester here at UT. It's really fascinating stuff but the inner workings are incredibly complex.

Anyway, this class, the coolest-sounding one I've ever taken, is not living up to its name. It's essentially a crash course in Electrical Engineering; no mechanics to speak of. It's interesting but it's tough, it's not taught very well, the textbook sucks, and I'm not good at it.

The lab is a bit more interesting. Thankfully there are no lab reports, but prelabs are insanely time-consuming and sometimes depressingly frustrating (seriously). I have spent over 6 hours on one or two before, even working with another friend. It wouldn't be so bad if the lecture actually lined up with the lab, but we get a crappy 50 minute lab lesson every week with an entirely new concept each time, and the prelabs require inside-and-out knowledge of that material.

Regardless, this week's lab was actually really neat, and almost fun if it weren't so challenging. It was a mock digital logic circuit design for a vending machine. I shouldn't have to tell you that it's way simpler than a real vending machine, but it was still an interesting mental exercise.

Pictured below is the final page of the prelab. Believe it or not, this is a simple logic circuit. It's NOWHERE near as complex as the electronics in, say, a remote control.

I'll explain what this is supposed to be later in the post.

 This is the closest thing to rocket surgery I've ever done.

Now do you understand why I have little patience for people that don't know how to USE electronics?

If you want to make the most of your day and learn something interesting, keep on reading.

This is the first thing I've ever done that actually used binary (1s and 0s; 1=true and 0=false). Binary and regular numbers can be interconverted, and it's actually easy to learn. The one weird thing is that it reads from right to left. The rightmost digit has a value of 1 and doubles every time as you move one to the left (<- 32 16 8 4 2 1). Every real number is a combination of 1s and 0s. A 1 means you count the number, and a 0 means you ignore it. So 001 is 1, 010 is 2, and 100 is 4. Logically, 011 is 3, 110 is 6, and 111 is 7.

 Hopefully this shirt makes sense to you now.

Okay, so why the binary lesson? Because binary is really freakin' important. It's used in almost every electronic device you own. It's worthwhile to understand.

Let me relate it to something you use all the time:

A 1 or a 0 is called a bit (b). 8 bits are called a byte (B). 1000 bytes make a kilobyte (KB), 1000 kilobytes make a megabyte (MB), and 1000 megabytes make a terabyte (TB). You've also heard the terms of kilobit and megabit, and those are usually used in telling you transfer or connection speeds (a DSL connection is typically 1.5 megabits per second, or Mbps, for download speed. That means your computer can receive 1.5 million 1s and 0s per second. The best part is that this is SLOW to some people. 30 megabit cable is not uncommon.)

Everything on a memory card or hard drive is just a lot of 1s and 0s that are bunched together in groups of 8s. Pictures are all 1s and 0s. Songs are all 1s and 0s. Games are all 1s and 0s. You get the idea. If you ever wonder why your computer says your hard drive or memory card have less storage space than what the box said, that's because computers take bytes in groups of 1024 instead of 1000. So don't worry; you're not getting ripped off-- you're getting all the bits as advertised.

 These things can go up to at least a terabyte-- that's a trillion 1s and 0s!

So, back to the vending machine problem.
There are 4 buttons (A, B, C, and D) on the machine: 2 for coin input, and 2 for snack selection.

The buttons are like binary: 1 for a pressed button, and 0 for unpressed. 4 buttons means 4 bits. They could be anything from 0000 to 1111; the bits are labeled ABCD in the circuit diagram.

If you separate the buttons by function, you get two sets of 2 bits: with 2 binary digits, you can have a total of 4 combinations: 00 (combo #1), 01 (#2), 10 (#3), or 11 (#4) and you can assign a meaning to each combination.

For the coins, 00 (#1) is no coin, 01 (#2) is a nickel, 10 (#3) is a dime, and 11 (#4) is a quarter.
For the snacks, 00 is no snack, 01 is a snack that costs $0.05, 10 costs $0.10, and 11 costs $0.25.

The vending machine has to decide whether or not to give you the snack you selected based on the coin you put in, what change (if any) to give you, and to return your money if you don't get a snack. This stuff makes intuitive sense but we had to convert it all into binary because that's how circuits work.

The two circuits we built in the lab collectively output the value of the first coin in the coin return (a second coin only appears if you buy the 5-cent snack or the 10-cent snack with a quarter).

So, either you will get no coin (00), a nickel (01), a dime (10), or a quarter (11) back.

Since each individual circuit only outputs either a 1 or 0, we had to make two during the lab: one for the bit on the right, and one for the bit on the left (e.g., a 0 and a 1, respectively, for a dime as the first coin in the return). The first circuit is the one drawn on the paper, and the second one is the picture of the actual circuit.

Again, this is not even close to the complexity of computers and cell phones or even a real vending machine. Don't take electronics for granted. Appreciate how mind-blowingly complex they are.

Text Trolling

At 1 AM, I got a text message from "jcortez78." I decided to have some fun with him. 

I retyped our conversation:

-Is this Bianca?

Nope, sorry

-Why no?

My name is Jerry.

-Your not ho I wanted to talk to… Jejej sorry

-U rnt going too forgive me ? ={

Is a stranger’s forgiveness over a trivial nuisance really that important to you?

-Ys actually ! I fel terrbl

Then I forgive you, random drunk person that I will never meet in the real world. Go and live your life in whatever way suits you best.

-You think im drunk? Just bcuz im mexican doesn’t mean im drunk! Rascist!

I didn’t know you were Mexican (good job not capitalizing your nationality, by the way) and I never said anything racist.

-Why your making fun of me not capitelizign my country? Thjs is textig not school

Your spelling and grammar are atrocious. I still think you’re drunk. Either that or your education (or lack thereof) is appalling.

-Your a asshole. Making fun of people just bcuz their from a different country

My insults were on the basis of your abysmal English, regardless of your country of birth.

-I can jst tell you hate Mexicans you rascist bitch.

Terrible at logic as well as English! Amazing!

-You self righteous dick, I bet you never get any pussy because of the way you talk

-Unless you are gay….?

Apparently you are not quite as bad at spelling and grammar as I had thought. But I will let you know that I do not talk like this to anyone other than those who mistakenly text me and then insist on continuing a conversation. As for the homophobic slur, that was quite amusing. You are so adamant against racism yet you encourage discrimination based on other criteria. Fascinating.

-Ther you go again with your condescending attitude. Why?

Because I find that doing so is very entertaining.

I win. 

Making a bomb.... FOR SCIENCE!

My professor for the physics class I've been taking all Summer, Dr. Turner, taught my dad back in the day. They're actually good friends (my dad did some research and some other stuff with him, etc.), and I didn't even know it when I signed up for the class. Before class at the second week or so he came up to me and knew my name without me even introducing myself- I had sent him an email before the class started, and he recognized the last name. He was on the lookout for me, and figured out who I was based on my similarities to my dad. I told my dad and that pretty much made his day.

Every other lecture he has experiments to show us, which are usually pretty cool. Most of the stuff today dealt with magnetism and electric current. They're always neat, but one of the cooler ones (no pun intended) today demonstrated what happens when a magnet is near a superconductor. The superconductor needs to be very cold to work, and liquid nitrogen fits the job perfectly. At 77 Kelvin (about-200 C or -320 F), there's no way you can accurately describe how freaking cold that is in terms we can easily grasp. I'll stop here, just short of a CSI-style pun.

Above a superconductor, a magnet will levitate, and will be surprisingly stable.

You can even spin it along the magnetic axis and it will go for a while since air resistance is the main thing slowing it down.

At the end of class, Dr. Turner decided to put some of the remaining liquid nitrogen to good use:

"There should be a law against wasting perfectly good liquid nitrogen."

My Weird Day in Austin (June 29, 2011)

I'll start with class today.
I'm taking Physics II (electricity and magnetism, also with a lab) this Summer at UT, and today's lecture fried my brain. It was a pretty intense class, most of it devoted to giving a qualitative explanation as to why circuits work at a microscopic/quantum level, followed by some esoteric equations and mathematical relations that went whoosh right over my head. By the end of class, my brain decided to call it quits for the day, and punched out as I left the classroom. (Also, it just so happens that my prof also taught my dad, and they're good friends. But that's another story.)

 

Today's lab.

I had an appointment with an apartment realtor almost immediately after class, so I hiked back to base and went straight to my car. I had seen where I needed to go on Google Maps before I left for class, so I figured it wouldn't be hard to find the place.

I was wrong. I'll spare the irrelevant details, but suffice it to say, class had indeed left me braindead. I eventually ended up at the place quite a few minutes late, but it turned out not to be a big deal. But being late meant that my day was about to get extremely... interesting. Timing is everything.

So we got into Steve's (the realtor) black car, which was pretty much an oven after sitting out in the near 100-degree sun. Somehow, it didn't bother me much. Apparently walking to class to back in record-breaking heat every weekday got me used to it. But I digress.

Steve showed me the first place, which was nicer than I expected. As we got out of the car at the second place, though, some guy asked us if he could have some help crossing the street. We walked over, curious, and it turned out to be a blind guy. And he was using a PVC pipe instead of a cane, apparently because some idiots in West Campus broke it. As we got close, he jokingly said "Guys, am I black? I need to know." It kind of took us by surprise, and it was funny in an edgy way, but it tipped us off that this guy was pretty lively, though also a bit odd. He introduced himself (I forgot his name) and shook our hands (it was just a tiny bit awkward). He then asked us where he was, we told him, and then he asked us how close we were to where he was headed. One thing led to another, and asked if he could possibly get a ride there. He seemed really nice and sincere through the whole thing. Steve looked really pensive for a few moments and then said yes, but first he had to show me the apartment.

When we got back, he was a little bit surprised that we kept our word. We went to the car, drove back to him, and he had a little trouble finding the back door handle. He had a cigarette, though, so Steve made him put it out first.

On to the third property. As we got out of the car, Steve told the blind guy that he could stay in the car or come with us. He came with us. He needed to hold on to my shoulder, though, so I walked slowly and let him know if there were steps or anything. About that time I was thought "Is this really happening? How in the HECK did I get in this situation?" When we got inside, he kept making comments about how nice the place looked, and how he admired the carpet, etc. His dry humor didn't work as well the second time around. It was also at this time that it became apparent that he was a bit more eccentric than we originally thought. So I guided him back to the car and we were off again.

Now things got even more interesting. As we headed to drop the guy off at the predetermined location, he changed his mind and asks if we can drop him off somewhere else. Later, he changed his mind again. I don't know why Steve didn't just kick him out at the first place. That's what was agreed on. But we had done this much, so what the heck. For the next while, we drove around as Steve made some phone calls. Blind dude asked if he could make a call, too. In the middle of it all, we talked and at one point he was elaborating on his cane situation. Turned out he can get a free ride to the government agency that sells 'em, but they cost $24. So then I took this video:

At the beginning, I was looking for his PVC stick but couldn't find it.
I ended up giving him all the cash I had, $22. I never give money to hobos, but I'm a sucker for poor disabled people. And this guy was pretty desperate, he said he hadn't eaten for days. Though he does receive welfare, his check was several days away, and he was pretty lost without his walking stick.

After that, we finally dropped him off and continued looking at apartments.

When I got back to my place, I needed a beer. Badly. So I found one in the cabinet and chilled it in the freezer. As I was drinking it, I just sat there, digesting the events of my day. I'm not too fond of beer, but, wow, was that satisfying. Then I downed some food (I hadn't eaten all day, and it was around 5:00) and took a sorely-needed nap. For the rest of the day, I just stayed inside and never seriously considered working out, though that was the original plan.

Austin is weird, indeed.

Bonus: I took this the other day on my way to class. This was across the street from campus:

My Past 48 Hours

TUESDAY evening:
I pulled an all-nighter for my Fluids lab report on pipe flow. (first true one all semester, I think. Several times I got just a few hours of sleep. Once I went to bed at 4 after working on a homework due at 8 and ended up sleeping through my alarm)

WEDNESDAY:
Put myself in a really bad position time-wise and I barely make it to the lab on time. I was 5 minutes late, which was probably near the end of the grace period- the rule is that late people have to leave after they turn in their assignments and come back next week to do the lab themselves (we get 2 weeks in between labs).
The lab experiment was pretty interesting- it was about drag on car models and drifting/slipstreaming, using two different wind tunnels. I get out about half an hour early.
I do my Matrices homework and pass some time in the computer lab in an attempt to relax.
Go to Matrices class and turn in my homework and start nodding off near the end of the boring lecture.
Bike back to my apartment and take a nap that lasted about an hour and a half. When I get up I'm extremely disoriented and confused for a while.
I bike to campus for my Mechanics of Solids (AKA Strength of Materials) discussion section. The quiz takes me way too long to do because I missed a stupid minus sign when copying over an equation.
Bike back to my apartment and relax for a while. I consider studying for my test the next morning but I decide first to get in bed to take a nap. I set my alarm for 9:30 PM, which would give me about half an hour.

TODAY:
My roommate's alarm goes of at 7am. I immediately sit up in bed, confused. Then I see what time it is and everything clicks. My Engineering Computational Methods test is in an hour and I have to ubercram for it. I do what I can and bike to the test room.
I do not so well on the test, as expected, but I don't completely bomb it. Afterwards I talk to one of my friends for a while and then bike back to the apartment and take a nice two-hour nap. Even after 10 hours of sleep, and a 2 hour nap, apparently I'm still sleep-deprived because it was pretty hard to get up from that nap.
I go to my Fluids lecture and realize that I had completely forgotten about the homework. Luckily I sit by my buddies from the lab and they help me out.
After that is my Solids lecture, and I started to go insane after over an hour of some stupid derivation for one simple concept. Luckily, after that we got some hints for the test that is on Tuesday.
After that I force myself to go to the gym even though I don't feel like it because I hadn't worked out since Monday, and, after all, I had gotten lots of sleep recently. I cut it short because it just wasn't going well.
I don't feel like walking back (didn't take my roommate's bike to campus this time because I only use it when I really need it) so I sit and wait for the bus.
Once I get on the bus, I start doing the sudoku in today's campus paper. They usually take me ~1.5 hours to do, but somehow I was able to crank this one out before I got off- took like 20 minutes from start to finish. So that was probably the best thing that happened all day. Either I'm getting really good at doing sudokus (recognizing new logical theorems/assumptions) or this one was much easier than usual.
After I got back to the apartment I realized that I left a bottle in the gym but I was able to text my roommate and he got it for me, so it worked out for me in the end.
Right now I'm finally in the clear- all I have to do is go to one class tomorrow at 2, so I'm happy now.

I forgot to post this a while back

My past phone went out of commission when the touch screen stopped working. I was going to get a new phone but a friend of mine suggested replacing the touch screen (also known as the digitizer) instead. I went for it since the part was a little over 10 bucks on eBay. There was even a YouTube instructional video on how to replace the part. Unfortunately, I had to virtually disassemble the entire phone to do so.










...and then I had to put it all back together again. It didn't fix the problem. Oh well, it was fun.