Me, Now on Facebook

That's right, as the title says.

The reason for this is due to my tutorial subgroup (5 people) in GE3239 Environmental Sustainability. My group members decided, wisely, that email communication is too much of a hassle for the online communication that we were supposed to do (this being a prelude to the collaboration with ANU students coming soon). So they settled on a Facebook group, which kinda forced me to sign up for it.

But it turns out that this tutorial group may just be temporary, since I think the lecturers meant it as a warm up to the necessary online communication with ANU students, and once the ANU-NUS communication is established, this tutorial group will be placed aside. What's more, even though the group got created, most of the work for the first tutorial was done via email, so it is currently pretty empty... a couple of members, but no files or messages.

So whatever it is, I have now a Facebook account, so if you want, you can try searching me out and adding me as a friend. But so far I find nothing spectacular about Facebook... So chances are, you won't see me online often.

Election in 2009? The Chances Involved

A new post in The Bosonic State, which is finally a direct comment on politics since eons.

Dying Keyboard

Two weeks ago I've opened up my Thinkpad T43 to examine the increasing noise from the cooling fan, which turns out to be a problem with the motor (nothing I can do about it). And since I was at it, I decided to clean the keyboard at the same time, since it's quite clogged up with dust.

So I took out all the keys and washed them thoroughly with soap. I also wiped the board with a slightly damp cloth. And while putting all back, I realised the first casualty of the cleanup: a missing "nipple", the blue spongy thing that acts as the spring to pop the button back up as well as a contact to trigger the circuit board.

Not too big an issue. I took the nipple from NumLock/ScrLock button, so now this particular button is permanently depressed. But it doesn't matter because I don't remember an occasion when I needed that particular button (I think Scroll Lock comes from an age long gone today).

After using my laptop for a while, more problems cropped up. Most obvious is that Left Alt + Tab no longer works. Left Alt works (with other buttons), Tab works, Right Alt + Tab works, but Left Alt + Tab just doesn't. I guess I must've killed some circuitry, such that only one of the two buttons can be pressed at any one time (just like how computers will complain when you press three arrow keys simultaneously). Now, that's irritating, because Left Alt + Tab is one of the most common shortcut I use on my Ubuntu. Right Alt + Tab just doesn't feel right (it requires both hands anyway).

Soon, I discovered the same problem with the letter "A" and "L", because when I type words like "real" quickly, the "l" may not appear. Then, the problem, I realised, can be generalised to the entire second row of alphabets: once "A" is depressed, "S", "D", "F", ... , "L" don't work (but other combinations, like "F" and "J", works).

If that's not bad enough, I've also found out that the Esc key doesn't function too well. In fact, it works only like 10% of the time. This key's not used as frequently as Alt + Tab, but it is used sometimes, and it kinda irks me when I have to press the key many times before the computer knows what I'm doing.

I'm considering buying a new keyboard and fan. Hopefully,nootherkeysfailinthemeantime.

My Project Stands on Dangerous Grounds

"You're stepping on dangerous grounds, young man."
- Berthold-Georg Englert

That's Berge's comment on some things in my project, during the second presentation that just took place yesterday.

Okay, okay. It's not as bad as it sounds. Anyone who knows Englert will know that he has killer eyes. But then again, anyone who knows him will also know that he is seldom harsh to students (at least undergraduates), even if he disagrees with what's being presented. In any case, he did say it with a tinge of humour in his voice (you know, the kind whereby a sagely grandmaster advises a young apprentice).

So indeed, he's a bit skeptical when I presented a master equation for quantum Brownian motion that has negative coefficients for the dissipators. The main issue he has with these negative coefficients is that they violate a sacred condition called complete positivity, which roughly implies that certain probabilities cannot be negative (naturally).

But you see, the situation is not as simple as stated above. The coefficients can be negative if, in a vague sense, they have been positive for sufficiently long periods prior to that. Specifically, there must be enough time when the coefficients are positive such that the eigenvalues of the matrix formed by these coefficients can be positive as well, even though certain matrix elements are negative. This will imply positive probabilities.

The thing is that this is a very delicate issue and difficult to evaluate for sure, which is his comment on "dangerous grounds". But then again, I didn't create this master equation which has negative coefficients. This comes from some published articles, and in fact this equation has been used by several authors.

Well, Yeo Ye is telling me to go ahead, because it's not too big an issue. Still, it's not very reassuring to know that my project (at least a part of it) is build on shaky grounds.

A Trip to Chek Jawa

It was a pretty successful trip to Chek Jawa on Sunday, after a couple of attempts at visiting it. There were numerous factors that could've spoiled the trip such as rain which seems itching to fall these few days, but fortunately almost all was smooth.

The "almost" was to justify the short moment when we got lost while cycling on the dirt track. The map showed that the route ought to connect to a track road, but it went in a circle instead. That, however, did not throw us off too long (we were there early anyway), and we caught Chek Jawa at the lowest tide of ~0.3 m and the intertidal region was exposed.


Chek Jawa exposed. If the water was a mere 0.2 m higher, this entire region will be flooded.



Fiddler Crabs. Plenty of them in the higher regions (which are also exposed during "high" low tides), so they're pretty much common sight.



I think these are the colonial ascidians.



Found this shrimp digging a hole by dumping out dirt. It was quite hard to capture it because it was constantly in its hole, coming out once every ten seconds to cast out some dirt (which rapidly blurs the surrounding water).



This should be a carpet anemone. It supposedly can stun a fish by stinging it and then swallow it in a popiah fashion.



Some eggs on the rocky shore. Not sure which organism it belongs to... Probably some snails'.



The obligatory group photo at the Ubin jetty.

Okay, next trip there, I'll make sure I get a guided tour so I can go down there.

Password Security

Recently, an email arrived in my NUS inbox concerning IT security. Specifically, NUS wishes to tighten password security by introducing a few requirements.

1) Passwords must be at least 8 characters in length.
2) Passwords must contain at least a number, an alphabet and a symbol (eg. Pa55Word!)
3) You will be required to change your password every 180 days.
4) You can change your password at most once/day.
5) You cannot re-use any of your 6 previous passwords.

Requirement 3, 4 and 5 are already in existence, which is pretty much one of the most stringent password requirements I've ever encountered. 1 and 2 are new, and while the former is reasonable, the latter is, well, a bit too much. Alphabet, okay; number, okay; but symbol too? Hey man, why not try this:



Can I suggest more? Ditch Internet Explorer for Firefox (some machines are still running IE6). Ditch Windows for Linux (at least for the mail server). But oh wait, NUS has a deal with Microsoft. Dang!

Galaxy Song

Here's a little song (and a video that is cheeky at one point) from the Monty Python Youtube channel to commemorate the International Year of Astronomy.