Journal of the Unknown Blogger

Just a reminder for those who haven't seen it yet, the first two acts of Dr Horrible's Sing Along Blog (an Internet musical directed by Joss Whedon and starring Neil Patrick Harris, Mal Nathan Fillion, Felicia Day and Simon Helberg) are out now, with the final one due tomorrow US time, so go watch them before they disappear. So far it's pretty awesome, it pushes all the right buttons.

I'm not usually one for celebrity crushes, but Felicia Day *swoon*. She's not only cute but talented all round. Aside from her acting and writing career (you should check out her sitcom about gaming, The Guild), she has a degree in mathematics and was a violinist. Why aren't there more women like her, sigh.

(I also have a small crush on Joss Whedon, but sssh.)

For those people who like keyboard-driven window managers like ion...

I've recently switched to a window manager called awesome, and it is indeed... awesome. It is easy to set up similarly to ion, is actively maintained, and doesn't have many of the quirks and bugs of ion. Spread the word to your friends.

Note that in the default setup, the Windows key is used for window management instead of Alt. The advantage is that it leaves the Alt key free for applications, but I don't like it because my thumb has to bend too far back to hit the Windows key, and I think it would be an RSI risk. It's nonetheless easy to change (Mod4 -> Mod1 in .awesomerc).

Awesome.

Can anyone suggest how I might mate this:



aka, a stepper motor drive shaft, with something like this:



aka, a steel leadscrew.

I was considering trying to drill an off-round hole into end of the leadscrew, but considering the difficulty of this and how close to round the stepper motor shaft is, I don't like my chances of pulling it off. Any better ideas?

Is there a standard time period that Australian banks will typically accept personal cheques? Over the years I've heard various numbers (6, 12 and 13 months), but I'm not sure which have any veracity.

Today's expedition to the zoo featured gay lions, swimming elephants, meerkats and much more...



( More photos (7) )

The bus that you just missed is running early. The bus that you're waiting for is running late.

Have any of you folks played with building low-power FM transmitters, whether from scratch or from kits? I'm wondering what the pitfalls of different designs are.

Today I discovered that if you keep pressing the top left button on my Nokia, say for example if you were to forget to lock the keypad, it keeps sending the last SMS you sent, to the top person in your address book (via Menu -> Messages -> Text messages -> Create message -> [cached message text] -> Options -> Send -> Search -> [top person] -> [confirm]).

Sixteen messages later, Abi called me to remind me to lock my phone.

Whoops. Good thing it wasn't anything salacious or otherwise compromising.

Here's an interesting mathematical exercise. I have a numerical solution which I think is probably right, but I'm still struggling to understand why it happens that way.

Imagine that you are a monkey working in an office (for most people this won't be hard to imagine). Throughout the day, at random points in time, jobs arrive in your inbox. You always process the jobs in the order you have received them, and each job takes exactly 10 seconds of your undivided attention. Assume that you can finish all the jobs by the end of the day, i.e. on average the jobs arrive less frequently than 10 second intervals (this may be harder to imagine).

Your manager keeps statistics on the latency of individual jobs, that is, the time between a job arriving in your inbox and the job being completed. She plots a histogram showing how many of your jobs have been completed in 10 seconds (i.e. with no waiting time), between 10 and 11 seconds, between 11 seconds and 12 seconds, and so forth. What is the shape of this graph?

So yesterday, while normal people were off doing normal things, this is what I got up to...



This is one of those circuits that I think every engineer ends up building once in their life, when necessity strikes. Can anyone pick what it is and guess why I needed one?

( Underside )

Dear Barnesey,

How on earth do you manage to put a 't' consonant in the middle of "feelings"? All this time I thought you were singing about the thetans inside you...

Impressed.

unknownblogger

Software always tends to get bigger over time. Even aside from feature creep, the net balance of code from fixing bugs tends to be positive: bugs are usually fixed by adding little patches here and there, and rarely by re-architecture that would reduce size. The problem can be especially bad in open source software, wherein every man and his dog submit patches and expect that it's their god-given right to have their code accepted into the official version.

I released rdesktop 1.6.0 today, and looking at the list of past releases it was interesting to note the sizes over time...

rdesktop 1.0.0 (Oct 2000):	49 KB
rdesktop 1.1.0 (Sep 2001):	79 KB
rdesktop 1.2.0 (Jan 2003):	123 KB
rdesktop 1.3.0 (Oct 2003):	134 KB
rdesktop 1.3.1 (Jan 2004):	136 KB
rdesktop 1.4.0 (Mar 2005):	198 KB
rdesktop 1.4.1 (May 2005):	211 KB
rdesktop 1.5.0 (Sep 2006):	239 KB
rdesktop 1.6.0 (May 2008):	278 KB

(Equally scary is the fact that 8 years have passed... The majority of the first version came together in Vienna and London, while travelling with the Physics Olympiad in July 2000. I had Windows NT 4.0 Terminal Server running in VMware Workstation on my then-spanky-new Pentium III laptop. I would wander around to find a nice place to sit, and then pull out my laptop and do some hacking. Ah, those were the days...)

Doing a Google image search for "chip on board", I was surprised to find page after page of people named Chip with their swines, and not many pictures of silicon wafers.

Turns out that, due to finger error, I had actually searched for "chip on boar".

Today, I turned over a new leaf.

I took down the Christmas tree.

Last night I went for bit of a photographic wander (with Keith C and Ka-shu, who some of you will know, being the small world that it is). It's been so long since I've shot anything, I barely remembered how to use a camera, but it was a nice evening to be in the outdoors. Here's one photo I took of the underside of an intergalactic cruiser which was parked in Sydney Harbour. Quite a feat of engineering...



Also, this is what we in the computing industry might call a side-channel vulnerability:

( Photo )

Gee let me think now... yes?

Photo from the San Francisco protests, taken by deadro.

My mum has a set of bathroom scales (manufactured by ZhongShan Oppel Electronics Co. Ltd.) which purportedly take CR2032 batteries.

However, the way the battery contacts are designed means the sides of the battery must be negative. Whereas all button cell batteries I know of are positive on the sides.

I suspect that perhaps the manufacturer might have got a strange batch of batteries from their upstream battery supplier, which were manufactured the wrong way. Unfortunately, my mum threw out the old batteries, so I can't check.

Anyone else seen this sort of thing, or know of any button cell batteries that have negative sides?

Edit: Never mind. It also looks like the two actuators that switch it when you tap the scales are broken (flimsy ****), so I'm going to give up trying to resurrect it.

Edit 2: I managed to separate the glass top from the electronics and scrub off the decal, so I now have myself a beautiful piece of thick green glass with chrome circular things at the corners — that matches the rest of my decor. Not sure what I'll do with it yet, but it's nice to salvage things that might otherwise go to landfill.

Today was the last day of the last six years of my life.

Tomorrow, a new chapter opens.

My response to this thread about LJ removing the basic account option for new users. Just thought I'd repost here since it will quickly get buried in the avalanche:

If we're to believe that it's about streamlining the registration process, why not retain the option to 'downgrade' on the manage/account/ page?

Since you've promised to retain basic accounts, presumably the code supporting basic accounts has to stay in the site, so that doesn't seem like a big deal.

Listen to brad, he has good intuition. LiveJournal is kept alive by having a critical mass of content and social groups. This depends on user loyalty and people feeling in control of their journals — both paid and free users, the latter being important for the critical mass. If people don't feel they are in control of their journals and that LJ is not listening to them, they will vote with their feet and go to the next new shiny clean Web 2.0 site that gives them what they want (and use LJ to tell their friends). If you turn LiveJournal into a MySpace, it's going to die like a MySpace.

Independently choose three random numbers between 1 and N, inclusive. What is the probability that they are all distinct?

I need this for some stuff in my thesis; I'm particularly interested in an algebraic solution, but specific answers for 4, 6 and 8 would also be helpful.

(My back-of-the-envelope answer is 1 - (N+2(N-1))/N², but I'm not sure if that's right, it's so long since I've done probability theory.)