Sunday, February 12, 2012

Food Science

Well, it's been awhile, etc etc, abandoned blog. Now for something interesting.

Right before moving back to the SF Bay Area last year, I got a call from a local food processing company. I had been jobhunting for the better part of a year and at that point would have taken anything. They asked if I could start in a few days. A friend of my mother's (of course, she's apparently big in the California food industry) was willing to hire me, without interview, and I found myself doing research and development. Though not quite what I was looking for, I was interested in R&D.

Fast forward to here and now - most of it has become assisting in developing formulas for new food products. As one would guess, much of this work involves finely tuning flavor. My boss is incredibly experienced in this, and his tastebuds seem to be finely-tuned machines, tasting the slightest hints of spices, off-flavors, and spoilage that often I won't even pick up, not even with the placebo of his suggestion.

This got me to thinking about the tastebuds in general. I understood their evolutionary purpose, and got the gist of their function, but never really thought about how they worked. I also remembered hearing, as a child, that the sense of taste and smell were similar. Having a degree in bioengineering under my belt (however useless it has been to me thus far - well - the economy is looking up apparently), I fathomed how they worked and marveled at how I had never thought of this before. Both senses must simply be molecular sensors. This is all speculation, but really, it must be something as simple as a protein or protein-complex with receptor sites tuned for different molecules, reporting to a nerve. One sense's molecular sensors are tuned to work optimally with gaseous molecules, or molecules suspended in gas, while the other's are tuned to work optimally with aqueous suspensions of molecules - I've read somewhere that you cannot taste anything with a dry mouth.

My thoughts then careened violently into possibilities of cyborg-like electrical noses, or tongues. The closest thing I've heard of are specific gas sensors, which rely on a specific gas reacting with something coated onto a wire, causing a change in heat, leading to a detectable change in resistance. This is how breathalyzers work. But there must be hundreds, thousands, maybe hundreds of thousands of types of molecular sensors in our noses and mouths in order to provide the vast array of detectable smells and tastes to us. Or are there only a relative few, but with varying proportions of each type of molecule, or perhaps varying fits/reactions to the sensor proteins causing variations in nerve response. I wonder why I never learned any of this in my advanced biochem or biotechnology courses.

I just remembered my boss gave me an article on sweetness-receptors and the comparison of the molecular structures of the different artificial sweeteners that I never read.

Maybe I'll stick to food science after all.

Thinking about the whole smell/taste sense being linked tale, armed with this knowledge now, I wonder if the whole "pinching your nose" trick is a baseless myth. It was supposed to numb your tastebuds, but I remember vividly tasting full-strength bitter gourd while trying it as a child.

Oh, and here's a pic of some "broken" monitors I found in the e-waste at work, they just needed some new capacitors/power adapters. For some reason they love destroying the stands though.

Sunday, April 10, 2011

Laptop Repair

I've been on a roll with repairing things lately! This one wasn't for me, however. My client had dropped the laptop, and the monitor cable had been severely damaged. Apparently it worked for a while, even with nearly all of the insulation melted off and shorts everywhere in one section of the cable. I just replaced the section of cable with some ribbon cable.
Melted insulation, we meet again.

It works!
There was shielding over the wires before, however, and now there is none. The state of the laptop is so bad, however, I don't see the owner keeping it for longer than the circuitry will last without shielding, and it shouldn't be a problem anyway if it's kept away from interference.

Friday, April 8, 2011

I've resurrected my router!

A long time ago (December 2005 actually) I was fed up with my wireless router's crappy performance. I had a Microsoft MN-700. I later found out it was pretty much an Asus router with Microsoft plastic and firmware, and that the firmware was just terrible.

I stumbled upon this guide to replacing the router's firmware with an open-source Linux-based firmware, and got to work. In fact, I think this was one of my first excuses for installing Linux. The router came preloaded with a bootloader that wouldn't accept the firmware I wanted to install, so I had to flash a new bootloader through a JTAG connection.

I later learned that this JTAG wire was too long and was causing flash errors.

Flashing the bootloader, in Windows 2000!

New shorter JTAG cable.

After a couple tries, I couldn't get a successful flash. And with each try taking hours, it didn't seem worth it to keep trying. After all, I had no idea what I could have been doing wrong.

I recently read another guide on it, this one claiming it takes several tries to get a successful flash. I thought, why not try again? The router and JTAG cable had been sitting under a bed ever since, being useless. I needed Windows XP apparently, and didn't have it on my computer, so I actually resurrected an old PC with a capacitor replacement and new psu (the one from this post) for the flash. It went through on the first try. I couldn't believe it.

I have another router now though, so I have no idea what I'm gonna do with this one. It's not worth it to sell, new G routers are like $30. If it had a USB port (to act as a print server) I could turn it into a wifi radio, which I really want to do, but it doesn't (although the datasheet for the Broadcom 4710 says it does...).
I'll think of something.

Saturday, March 19, 2011

Urdnot Wrex Portrait/Cardboard Back-Loaded Horn Update

I just realized I never updated the speaker project (also here). It's been done for more than a year now! Credit for the painting goes to my former roommate. Wrex watches over my kitchen now.

It's hooked up to a Sure Electronics class D amp right now, sounds great (though I still wish it were wood, and that I had two).

Friday, March 18, 2011

Getting rid of annoying mouse cord overhang (ipod nano 6g review too)


I love my Logitech G500, and the braided sleeving on the cord is pretty cool. I recently started using a sliding keyboard tray (new desk) and noticed that now my mouse cord hangs down and if I make any sort of vertical movement, the following happens:

It frays the braided sleeving and is annoying, obviously. I taped the cord up under the desk surface, but that didn't allow much play: I had to constantly adjust for the perfect amount of play for the most neutral mouse moving. By the way, if you're thinking "why not just get a wireless mouse?", I have two, and they both suck in comparison to this mouse, and I can't justify a new one just because of this little issue. I'm also notoriously worrisome about batteries and think about them constantly when using wireless mice.

While browsing the dollar store recently I happened upon some little hooks and thought, "PERFECT -- and cheap". It is non-binding, smooth, and I can easily remove the cord when I want.


Also, after years of being an Apple-hater, I turned out to need (exercise) an mp3 player, and my cousin just had an extra ipod nano 6g laying around: she won it, but she has an iphone already. I've actually won an ipod shuffle before, and sold it. My mother won a nano 4g and gave it to her brother... It's like they're attacking my family.

After getting over my hatred and reluctantly installing itunes (seriously? no drag and drop or standard MTP support? I NEED itunes to use this crap?), I had an ipod nano 6g with my music. I almost returned it after I found out I couldn't sync music without itunes, I have memories of friends with itunes and seeing 3 apple-related processes with it closed, something like 5 when it was open. I caved and installed to my non-primary laptop, I almost virtualboxed just for itunes.

The screen is incredibly nice, the pixel density is surprising, making for a surprisingly sharp picture. I can actually tell the compression/low-res of some album art on the screen! And I mean low as in ~150^2 pixels. For some reason, however, you cannot set a wallpaper different from the provided stock-wallpapers, which is completely idiotic unless I'm missing some setting.

I'll admit, I'm guilty of looking at them before: I'm a sucker for album art, and the UI displays AA while playing just like the Windows Media Player 12 it doesn't support... I also saw the watch-bands on some tech blogs and thought: wow, that is nifty, perfect for running as well, because the clip seemed flimsy and would not hold it in place anywhere on my clothing if I were to run with it. I thought maybe I could do similar:

My mother got me the star of david bracelet when she went to Israel, I found that it worked somewhat well, but it was loose and the styles clashed.

I later bought a cheapo watch just for the continuous-strap band, and, presto! Not... clashing, very secure, and easy to remove/put on thanks to the hook/loop.


The interface is surprisingly easy to use, as I had an aversion to touchscreens prior, and was looking at the Clip+ for fulfilling my jogging-companion needs. I wanted to be able to do certain things without looking at the device, and with the latest firmware, I could "next track" (the action I do most often, second only to volume adjustment) with a double tap to the power button, which tripled as a hold switch, and there are dedicated volume buttons. To "next track" I can shake-to-shuffle as well, since I'm always in shuffle mode anyway.

Navigating lots of music on the tiny screen was another aversion to a tiny player I had, but the hold-for-alphabet-browse feature let me get past that: one can hold a finger on the right side of the screen while browsing to slide to a certain letter.

Regarding file formats, I really wish I didn't have to let iTunes convert my wma's to INCREDICRAPPY mpeg-4 audio files. Also, it wouldn't even consider my oggs. Really. That's how much they hate open source... that they don't profit from (since their computers are pretty much on FreeBSD). I nearly uninstalled/smashed the ipod at that point.

The pedometer seems to work, and I suppose will be a nice way of tracking my progress (oooohhh I see some graphs in this blog's future).

The radio works well, although reception is a bit hard to get sometimes depending on the headphones.

The concern I have that killed my last player was a worn jack, worn from abuse and several headphones. The left channel was extremely intermittent and unreliable. This unit's jack seems solid enough, but only time will tell.

The sound quality is decent. Bass is exaggerated for the bass-heads (I'm guessing at least half of the userbase listens to primarily hip hop), and so is the treble. As a result, the mids seem just a tad recessed in comparison. It's slight enough for me not to care, I guess I'm not an audiophile anymore.

Overall, I love the hardware and most of the user interface, but I still hate the software and company. I didn't even know what jailbreaking was until I had this thing, and now that I do, my opinion of Apple is even worse in that regard. I can at least sleep at night since I didn't directly give Apple a dime.
Other than that though, it is a great jogging companion, especially with the watchband.

Thursday, March 10, 2011

Bye bye, Berkeley. Drawing + PC repair + Wacom Bamboo Pen & Touch


I'm now (unofficially) a UC Berkeley grad. Still waiting on getting my diploma in the mail, however. Also looking for a job. Anyway, enough of that.

During the last semester I was able to take up drawing. My friend dragged me onto, where I was reluctant to start. I knew I had the typical couldn't-draw-to-save-my-life skills but then realized soon that I could draw humans better than she could, with my mouse. I then started studying color theory, more anatomy, poses, dinosaurs, and even started the book "Drawing on the Right Side of the Brain" by Betty Edwards. At one point I was doing a study of facial features, by pencil, and just drew for hours on end, not realizing where the time had gone. Eyes, then lips, then noses, page after page of sketches: some from reference, some from imagination. For the first two weeks, I saw the world in a way I had never seen before, everything looked brand new to me.

There was a point where I did nothing but draw, for two weeks. After that I came to my senses and started doing schoolwork again, but then after about October or so (when I had finally purchased a graphics tablet, ironically), I stopped.

Here's an early iscribble work (yes it's terrible, this is before I studied color as well): my first time drawing a dress. Since it's early it's very cartoony (I started anime-style since everyone was doing it on the board) but have since then begun learning realism. I was still struck at how I was able to spew this onto my screen, where I could only spew stick figures before.

In other news, I was at a LAN party recently, where a good friend of mine whom I had not seen in a while had a broken power supply. I had read up on capacitors going bad and had my suspicions. It was a Cooler Master 550 watt, and for a while it had to be plugged in for hours before the PC would turn on. After that it just quit.

I looked at it for a while, and sure enough, there was a busted cap. The cooling fan was also very much stuck with dust, and one of the toroids had burned through its cloth-like shroud. I bought it off him for $5.

I had an extra 120mm cooling fan laying around, but no extra 2200 uF 10v capacitor. I was about to order some (no point in buying just one online, right?) when I remembered I had an evil Bestec power supply in an old emachines I had laying around. It wasn't broken, but it had claimed the lives of two motherboards before I searched about them and learned of their destructive 5v rails. I ripped it open, by removing the screws with a philips screwdriver, and found a 2200 uF, 16v cap with the correct lead spacing! I slapped that into the CM550 with a soldering iron and bam, working power supply! Tested on my system (risky, I know, but it passed the false-on test displaying all the necessary voltages confirmed by multimeter) and it seemed stable. The Bestec had some busted, leaky caps so I still don't trust this CM550 completely, but I now have a backup psu that may see action soon for a backup computer if I get my hands on a cheap 775 proc anytime soon.

More on the tablet, a sort of pseudo-review:

Once again, this is the Wacom Bamboo Pen & Touch. Please forgive my lack of a tripod. Digital artists everywhere seem to swear by Wacom, and the friend who had gotten me into drawing in the first place had a Bamboo Pen. The Pen and touch features twice the resolution, four buttons on the tablet, a pressure-sensitive eraser on the pen, and it is also a touchpad. Right off the bat: the touchpad is terrible. It may be inherent to the device or it may be the drivers, I don't know. I just know it's sluggish, unresponsive, and a tiny bit of sweat on the tablet from intense drawing registers as constant input to it. Thankfully it can be turned off.

Drawing on it is great, however. I thought I was going to use it in relative mode but absolute mode is wonderful, I can get to where I need to be on the screen with incredible speed. I wore a flat to the tip in less than a week! This caused some awkward scratchy sounds until I realized the tip is simply friction fit and you can pull and reposition it. I rotated it 180 and it's fine now. Just like a pencil that you can't sharpen, you should wear the tip evenly and rotate it from time to time.

In Gimp and Sai the pressure sensitivity is recognized, as well as the separate eraser. If I'm on iscribble I get neither but that's understandable. What's odd with iscribble is that it's insanely laggy on Windows 7, maybe from all the different features aimed towards tablet PCs that are loaded and active while it's plugged in. It is unbearable. I boot up Fedora and while it took a bit of work to get the drivers working, it is lightning fast. However, drawing in Gimp in Fedora occasionally misses a stroke, I'm going to assume it's the drivers for that fault. Linuxwacom (driver package) doesn't even recognize it as a Bamboo Pen & Touch, it reads "Wacom BambooFun 2FG 4x5" under devices, but I suppose it works well enough.

Regarding the aspect ratio of the device, it is 16:10, which mapped perfectly onto my 16:10 22", but now I'm on a 16:9 24", with proportions forced. A small amount of the tablet is unusable as a result. However, it's nice that you can select which monitor and what portion of the monitor to map to. This is done in Linux with a couple commands in the shell (and some simple pixel math), whatever, I wrote a script to take care of it.

Although ironically I almost stopped drawing soon after I got this tablet, I'm starting to draw again and am glad I got it.

Sunday, June 20, 2010


I guess it's way past due for an update.

The 2010 California Formula SAE competition has just finished yesterday. It was one crazy ride. So intense but so much fun. It is also so refreshing and interesting to see the other cars from schools all over the world.

I took some pictures but didn't opt to bring my camera, so they're crappy camera phone pics, for better pics search for "Cal Racing" on facebook, but our historian hasn't uploaded any pictures/videos at the time of this writing (he's probably on his way back home right now).

While I wanted to get involved in a number of things on the team, I ended up doing wiring. I started with some chassis fabrication (tube grindin'!), and general tasks during engine dyno testing. I've always enjoyed wiring, but have never focused this much on making a safe, reliable, and attractive final product. I have learned so effing much about automotive wiring, but I'm still a rookie and there is much more. I really do wish I could get into other disciplines like chassis, suspension, engine, composites, at least a little bit with the little time I have left on this team.

I regret so much not joining immediately freshman year. I have never worked this hard for anything in my life, and my job isn't even that hard.

Auto Club Speedway

Some of my wiring

University of Illinois - Urbana

University of Oklahoma

UC Berkeley getting worked on

Vellore Institute of Technology [India] (University of Leeds members shown also)

University of Leeds [UK] (Vellore Institute of Technology members shown also)

Montana State University - Bozeman

University of Illinois - Urbana Champaign (University of Alberta 2009 car visible on right)

University of Saskatchewan [Canada]- Tech Inspection (UC Davis visible in background)

Universidad Autonoma Estado Mexico - Tech Inspection
Crazy bodywork!

Chitkara Institute of Engineering and Technology [India]- Tech Inspection