Thursday, August 26, 2010

Fun with (caffeinated) numbers...

I saw this post on Slashdot earlier:

This is a student project so the correct unit of energy is a "Library of Congress Stacked with Red Bull Instead of Books."

Now, you may convert that into Joules, if you care to.

I couldn't pass up that challenge...

The Library of Congress has 1,199km of shelf space.
A Red Bull can is 52mm in diameter.
A 250ml Red Bull can contains 481kJ of energy.

Doing the sums, I made the following estimate.

Assuming a single row of cans: 23,057,692 cans, and 1.109x10^13 Joules.

If we have a nominal shelf depth of, say, 250mm - let's call it 5 rows of cans - we get 115,288,461 cans, and 5.545x10^13 Joules.

For comparison, a kiloton of TNT releases 4.184 terajoules, so a Library of Congress of Red Bull contains the equivalent of about 13.25 kilotons of TNT - about 1 Hiroshima Bomb, give or take.

Fascinating stuff.

Tuesday, August 10, 2010

A taste of the future?

Headline from a news story this morning:

"Morgues fill as deaths double in sweltering Moscow"

Now, some of you will say "that's weather, it's got nothing to do with climate change". And you'd be right, mostly.

The difference is that, in a warming world, we can expect that extreme heat waves (and the forest fires that go along with them) will become more common. Already, record high temperatures are more than twice as likely to be broken as record lows. The last winter in Europe & the eastern US brought very heavy snowfalls & low temperatures. It was the coldest January in the UK for 23 years, according to the UK Met Office. At the same time, it was unseasonably warm over much of the Arctic, & the northwest US & western Canada (remember the problems they had with not enough snow for the winter olympics? They had to truck it in to some venues!).

Since then, it's been a pretty warm year. This Wikipedia page, listing all-time record temperatures for various countries, shows no less than ten new records have been set so far in 2010. Another 12 have been set in the last decade. That's all-time records, folks. 22 out of 58 have been broken in the last ten years.

The NOAA says that the January to June 2010 period was the warmest 6-month period on record. June 2010 is the warmest June on record, and is the fourth month in a row to set an all-time record.

Indications of a warming trend? Well, not in isolation, no - there's too much variability in weather for climatic trends to be statistically significant for anything less than about 15 years worth of records. However, it's certainly consistent with a warming trend. And if we go back far enough to get that statistical significance, there is quite a definite trend, so it's more appropriate to ask: "are current temperatures indicating any change from the previously established warming trend?" The answer is a categorical no. If anything, the current temps are tending toward an increased warming trend. There's definitely no evidence whatsoever that global warming is showing any sign of slowing down, more the opposite.

Back to heatwaves, the more serious implications are raised by this post on Skeptical Science. There comes a point where the human body is unable to shed heat, and body temperature starts to rise. At that point, you'd better have somewhere cool & air-conditioned to hide, or heat stroke is just a matter of time (just look at that Russian contestant in the Finnish sauna competition - 6 minutes in a 110º sauna, and he keeled over and died).

So we're looking at some nasty consequences for our high-carbon diet over the past few centuries. (And those forest fires & peat fires are releasing even more carbon!)

A nice analogy I saw on another post on Skeptical Science: if you crash your car into a concrete wall at 80km/h, there's a small chance you'll walk away with just a few bruises. But is that any reason to drive straight at it?

Sunday, May 23, 2010

Bagels FTW!

Sourdough bagels, that is.

Had one this evening with dinner.

Had a decent dinner, so was feeling quite full when I was done.

But I still wanted another bagel...



Monday, May 17, 2010

Sourdough #3

I'm getting the hang of this...

This week, I didn't want to waste a lot of flour/water by feeding the starter every day, so I fed it on Sunday night & plonked it in the fridge. Left it there until Friday, when I pulled it out and give it another feed. It had developed plenty of fine bubbles over the five days, but not quite as many as it had previously developed in a 12-hour period. 4-5ºC will slow things down a bit, which was the intended outcome.

After a day out on the bench (in some much cooler weather for Brisbane, ~15-20ºC), it was nice and bubbly again, so I gave it another feed to bulk it up on Saturday night, and made the loaf on Sunday morning.

It's still a bit time-consuming to make a sourdough loaf, but it's satisfying at the same time. Flour, water, and salt were the only ingredients, plus some sesame seeds scattered on the top. (Yes, I remembered the salt this time!)

So, without any further ado, here's loaf #3, 100% pure sourdough.







Two comments:
1) you've probably noticed I baked this one in a tin - thought I'd try it out, see how it goes - the shape is much better for toast / sandwiches, but maybe I'll buy a narrower tin, this one is pretty wide, and a higher-but-narrower loaf would be even better;
2) you've probably also noticed why it is sourdough loaves are usually slashed on the top - that oven spring is wicked! :-D

Tastewise, it's nice bread - a bit 'heavier' than commercial bread (this loaf was over 1kg, compared to a commercial loaf of bread that's a bit bigger weighing in at 700g), but with a nice texture and chewy crust. Makes great toast. A very mild flavour on this one, though, not very sour.

Saturday, May 15, 2010

Quote of the week

"But [scientific] journals have lots of big words, and lots of small print, and very few illustrations to make it easy for me. You can see why climate deniers don’t like them."



From the enlightening Climate Denial Crock of the Week.

I thought Viscount Christopher Monckton was getting it wrong, I just didn't know *how* wrong...



Friday, May 14, 2010

Mobile data rates

Here's a bit of a rant.

Device A connects to the internet via a 3G (UMTS) cellular network. So does Device B. Same carrier, same cellular network, same UMTS technology used to transmit & receive data.


For Device A, a $30/month plan includes 2000MB of data.
For Device B, a $30/month plan includes 500MB.

For Device A, when you exceed your quota, you pay $0.06 per MB for excess usage.
For Device B, when you exceed your quota, you pay $3.00 per MB for excess usage.

Same network, same data, from the same websites. But Device B pays 50 times more per MB for excess usage.

Device A is a 3G wireless internet modem you plug into a USB port on your PC or laptop.
Device B is a phone - which is why I'm not objecting too much to the different included data, because that $30/month also includes a fair amount of voice calls.

However, if you consider voice calls to be yet another form of data, it gets much, much worse.

GMS voice calls use about 30kbps worth of bandwidth for a digital voice signal. That's 1800 kilobits per minute, or 225 kB per minute. 0.225 MB per minute. At the $0.06/MB rate, that's 1.35c/minute. At the $3.00/MB rate, that's a princely 67.5c/minute. The actual call rates on the plan for Device B are 80c/minute.

If we priced voice & other internet data at the excess usage rate of Device A's plan, it would cost Device B $5.23 for the included voice data, and $30.00 for the included internet data.

Not too bad, $35.23 of value for $30!

But it would cost $120 for the data included in Device A's plan, which suggests the *real* cost of data is something less than the $0.015/MB that the included data for Device A is charged at.

That would price Device B's plan at something more like $8.81 for the included data.

However, I can live with paying a bit more for the GSM voice data, if it's given priority transmission to ensure good audio (having bits of lag here & there is bad for voice call quality). So I can live with paying $30/month for something that costs the carrier less than $9.

The worst bit, though? If you actually used a combined total of 2000MB of data on the phone, you'd pay a minimum of $4,500.00 in excess usage fees.

If both devices use 3000MB, Device A gets charged $90.

Device B gets charged $7,530.00.

For the same data. On the same network.



How is that even legal???

Monday, May 10, 2010

Further Adventures in Bread-making

Sourdough FTW!




Absolutely delicious, and, if I do say so myself, pretty bloody good for a first attempt, even if the shape isn't quite there.

Sourdough loaf #2 worked out pretty well, too - if a little bland, because I forgot to put in the salt. D'oh!



And here's a pic of the starter. Flour, water, and time. That's all! :-D

Here's the dough for the first loaf, being folded after rising, just about to go into the floured banneton.

Tuesday, April 20, 2010

Freecell fail...

Bugger!



I was doing so well, until I tried to play a game while having a conversation with someone...

Let that be a lesson for you, boys & girls - don't talk on your phone while playing Freecell!

Water aerobics class halted by croc in pool

I kid you not.

Only a freshie, I've swum with ones nearly that big up at Lawn Hill. Perfectly harmless... well, unless you annoy them, anyway. :-D

Things that can kill you

Here's a nice summary of some of the wildlife here in Oz...



Found on the artist's site, via How To Spot A Psychopath

Saturday, April 17, 2010

Taxi!

Well, there's an interesting story...

John Cleese, comedian extraordinaire, is flaunting his wealth. Well, not really.

He's just catching a cab.

From Oslo.

To Brussels...

For the geographically challenged among you, Oslo is in Norway, Brussels is in Belgium. That's three whole countries away from Oslo... Seriously, go look it up in Google Maps or something. :-D

Seems like a lot of people are grounded by that whole volcanic ash cloud thing, and are keen to get home. Mr Cleese intends to catch a train from Brussels to London.

Good luck with that, sir!
(Hope it's not already booked out...)

Thursday, April 8, 2010

One of the scariest videos I've seen for a while...



Someone was very, very lucky this day...

I thought it was a bit scary how close people were to the launch point. But the end of the flight is much, much worse.

Saturday, April 3, 2010

More Easter Hot Bun Goodness



Batch No. 2, fresh out of the oven.

Did the sugar/water glaze, this time - works quite well.

The buns are very tasty - I used a recipe out of a 1973 cookbook from my mum's collection, except I put in about 5 times as much spice as they suggested (I like my hot cross buns to have flavour!)

As you can see from the photos, I still didn't use a big enough pan. So, next time, I'm going to (a) make the buns individually a bit smaller, and (b) use two pans, so they're not so squished together.

They also had an issue with splitting/cracking on one edge - seems there was a lot of oven spring in these buns. If I leave them to rise a bit more before cooking (which I can do if they're spread out a bit more in two pans), maybe they wont do that so much. Or maybe they'll just have more room to expand without being forced upwards.

Anyway, will give that a go in a week or so.

Stand By Me - Muppets Edition

Monday, March 29, 2010

Freecell pwnage!


Well, maybe not exactly pwnage... but a respectable effort, I think - that's 50 wins IN A ROW, suckahs!

Thursday, March 25, 2010

It's Easter time!

And you all know what that means!



Ok, so I should have used a bigger pan to cook them in... they do look a bit, um, squished together...

Doesn't change the taste, though!

Here they are with a glaze added - just some melted jam (used plum, because we had some in the fridge) brushed over the top.



Personally, I think I prefer a bit more spice in my hot cross buns. Maybe next batch I'll use 4 or 5 teaspoons of mixed spice, instead of only 3...

Oh, and the taste?

Absolutely freakin' delicious!

Had to resist the temptation to eat the whole lot in one go, still warm from the oven...

Sunday, March 21, 2010

Adventures in GUI programming

So, I've been dabbling with a little Qt programming.

I wanted to develop a program that would let me do an easy search & replace for objects in ArmA2 map files. Naturally, while I could potentially write a CLI program, it would be much easier for me (& others who might use it) to have a GUI interface. As I thought writing a windows app would be in the too hard basket, I decided to try out the Qt GUI toolkit.

Not only that, but I installed the NetBeans IDE to do the programming in. The old DevCPP that I've been using for years is still very good (and I've written quite a few CLI C/C++ programs with it), but NetBeans promised to make Qt programming a lot easier.

Shame it didn't make installing all the required software & packages easier... I was rather disappointed, upon downloading the tools I needed, to see that I was promised an almost single-click installation experience - except on Windows.

This is a problem, because ArmA2 is a Windows-only game, so naturally I wanted to do the development in Windows. Not that it really matters all that much where I edit the map files from, but being able to fire up some of the official Windows-only editing tools to check stuff is pretty important.

Needless to say, I did eventually get everything working. I even got the proverbial "Hello World" application to compile & run.

Then I upgraded Qt from version 4.5 to 4.6, and broke everything again. :-(

Took me several hours to fix that problem, which probably says more about my lack of computing knowledge than anything else!

So, I started to code up my app. Quickly figured out how to use the Qt Creator to lay out the application window, with various buttons, checkboxes, and the like. Even figured out how to assign signals & slots to those things that needed them.

I had a moment of feeling pretty chuffed when I got the "exit" button to close the application. :-D

Now I've got the file dialogs working. You can select the input file, and the output file name. It'll even pay attention to those little "read only" & "allow overwrite" checkboxes I put in there.

Then it was time to do the hard part - actually read in the map file.

Well, with the Qt Reference Guide open on the second monitor, it wasn't all that hard. Except for the bit where I couldn't get it to read a float - it kept giving me doubles... turns out that was a compound problem. I was using the reference docs for Qt 4.5, not 4.6, and there's a change between those versions that means a QDataStream defaults to reading double-precision floats, not single.

Fixed that, and had another moment of feeling rather chuffed when I read in the file header (containing 7 or 8 different variables of five different types), wrote it out again to the output file, and compared the two in a hex-editor and found they were byte-for-byte identical for the header. :-)

As I said to the missus earlier - that's 72 bytes down, only 90 million to go! :-D

Wednesday, February 24, 2010

Holy freakin' COW!

There's this chemical.

Dioxygen diflouride.
(No, not dihydrogen monoxide)

O2F2.

Some chemists write it as FOOF - and for good reason!

This stuff explodes when you mix it with other chemicals - and that's way down at -180ºC! I'd hate to see what happens when you try to do anything with it closer to, I don't know, the boiling point of liquid nitrogen?

Apparently it just can't be warmed to room temperature without Bad Things (tm) happening...

One example reaction: 4O2F2 + H2S -> SF6 + 2HF + 4O2 + 5920kJ/kg of energy

On an energy basis, a kilo of this mix would be as productive as, say, 1.3kg of TNT. Yes, the stuff that goes bang.

Nasty stuff...

via via

Saturday, January 23, 2010

Engineering FTW!

Here's some of the most impressive engineering I've seen in a while. This is why we need engineers - either that, or a hell of a lot of very poorly paid manual labour (thus china's rise).

Sunday, January 10, 2010

A new toy!

Went to Dick Smith today & bought a Logitech Harmony One universal remote.

The most surprising thing about that was that Dick Smith actually had one of the cheapest prices in Oz for it... for those who don't already know, Dickie Schmidt's been moving away from it's electronics/hobby store roots, and heading more down the white-box Harvey Norman / Good Guys / Retravision style path. Most of their stores even had a clearance recently where they offloaded all the hobbyist electronics stuff for low prices. Such retail strategy doesn't normally lend to low pricing, but a few online searches revealed there were only a few online stores where I could have got the remote cheaper, and most of them didn't have any stock. Plus I wouldn't have been able to bring it home today. :-D

Have only partially programmed it. It'll allow us to watch TV & play DVDs (turning on the TV, AV receiver, and DVD player and selecting the operational modes as approriate) so far, but I still need to configure it correctly to allow us to run the PVR (a chinese cheapie that nevertheless works quite well) and the WDTV. Also have to get a DVD player for the TV in the front room, so I can move the WDTV into the loungeroom.

Now that I've finally finished (no, really!) the speakers, we've got things somewhat re-arranged... those of you who have been here before wouldn't recognise the place! If nothing else, we've finally gotten rid of that old cane furniture we never did like. :-)