iTunes Berkeley

University of California (Berkeley) now has a whole lot of lectures available as downloadable audio. You can get Podcasts of them, or get them via the [iTunes Music Store, Berkeley edition][1]. I’m not getting them as Podcasts, since the ones on iTunesU are already pre-tagged, and the courses I’m getting are not currently running, so I don’t need to automatically get new ones. The only tagging fault I’ve found is that they are missing: Remember playback position Skip when shuffling Which I think are important for this type of thing. I’ve also noticed some Podcast/downloads via iTunes can be paused and resumed, unfortunately, these ones can’t. Finally, a neat point is that it automatically creates a new Playlist, and a new Playlist Folder.

[Snow][2] • [Alex Lloyd][3] • [Black The Sun][4] ★★★

[1]: javascript:openWindow(‘https://deimos.apple.com/WebObjects/Core.woa/Browse/berkeley.edu’,’_blank’,400,250,0); [2]: http://phobos.apple.com/WebObjects/MZSearch.woa/wa/advancedSearchResults?songTerm=Snow&artistTerm=Alex+Lloyd [3]: http://phobos.apple.com/WebObjects/MZSearch.woa/wa/advancedSearchResults?artistTerm=Alex+Lloyd [4]: http://phobos.apple.com/WebObjects/MZSearch.woa/wa/advancedSearchResults?albumTerm=Black+The+Sun&artistTerm=Alex+Lloyd

How train signals work

I learned something last friday, and I learnt it from some juvenile delinquents. I’ve often wondered exactly what signals, so to speak, a train is coming. What is it that enables the boom gates to come down and the light to start flashing? Last friday, I found this out. Some students, a couple from Scotch College, and a couple I take to be from Underdale High School, got off the train at my station, and one of them proceeded to run back towards the nearest level crossing. He squatted down over the state railway line, which seems to be marginally lower gauge than the local system. I was getting relatively close to where this boy was, but I don’t think he’d seen me. He reached his arms out perpendicular to the tracks, and pressed something, I assume a coin, onto each of the tracks. The lights then began to flash, and the gate started to come down. By this time, I had approached to being about two metres away from the boy. He saw that I wasn’t one of his cronies, and jumped up. A car had pulled up at the tracks, and thinking a train was coming, had stopped. The driver had their window down, and the boy said to him that no train was coming. I continued to walk, but as I was about 10 metres past the crossing, I took my phone out, and turned around and very blatantly took a photograph of the group. I very shortly turned around the corner into the street I walk down on the way home, and I think the gang had begun to disperse, perhaps fearing I had called some sort of authorities, as I did hold my phone to my ear. • So, what is it that makes the signals know when a train is coming? I assume that there is some sort of Ohm-meter, that measures the resistance between the two rails of the track. Normally, this would be very large, as they are not connected. It should, in theory, be almost infinite. That is, it should be an open circuit. When a train approaches, it acts as a conductor between the two rails. Since the rails have a resistance of some sort, albeit quite small, it would be measurable over the distance a train needs to be away from the crossing to trigger it. This, and the fixed resistance of the actual train would be a threshold. When this threshold is breached, and whenever the resistance of the system is less than this value, the lights would flash, and the gate would come down. The whole time the train is going past, it would hold the resistance below this value. After it has gone past, and exceeded a certain distance, the resistance would then have gone above the threshold, and the system would revert to the open state.

Cooking Eggs with Mobile Phones?

Boing Boing: HOWTO cook an egg with two mobile phones

HOWTO cook an egg with two mobile phones This site claims to provide instructions for cooking an egg by placing it between two live mobile phones

I’d very much doubt that this would be much different than just placing the egg right next to the antenna of a single phone when making a call. After all, it’s not like mobile phones connect directly to one another, is it? Don’t they connect to a base station?

Historical Weather for Robe

Weatherbase: Historical Weather for Robe, South Australia, Australia Apparently, the temperature at Robe has never exceeded 40°C, since records have been kept. Amazing things you can learn on the internets, nowadays.

I made some science.

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UK professor concludes: cellphones don't cause gas station fires

(http://www.engadget.com/entry/1234000073036833/ “UK professor concludes: cellphones don’t cause gas station fires”]: He studied all 243 gas station fires from the past 11 years that were supposedly sparked by cellphones and determined that not a single one was actually caused by a handset. The actual cause of most of these fires? Static electricity, which is what everyone who actually knows anything about this stuff has been saying all along. via Engadget.

[composed and posted with ecto]

Aristotle & Science.

I’d never really come across classical philosophy until partway through my Education degree. We did a philosophy of education subject, and around the same time I happened across Stephen Jay Gould’s books. And I realised how some historical figures - most notably Freud & Aristotle have shaped our ideas of the world. And in some cases held back the progress of science by decades, or even centuries. The most obvious examples are the elements, and the planets. Aristotle pushed for the acceptance of the 4 Elements theory - Earth / Air / Fire / Water, and it took centuries for more reasonable theories to take over. Four of anything is usually pretty neat - especially if you can pair them up on axes at right angles to one another and have a continuum. And having four elements means you can associate them with your four humours. Now there’s a classical mistake that cost countless lives! The furore over planetary gravitation is another cause of concern. The most worrying thing is that there were Classical Greek scholars who decided that the Earth orbited the Sun. But not Aristotle. Think of where we might be now if we’d figured this one out 2000 years ago. Freud and his fixation on sex held back psychology decades. And his work was all based on half a dozen patients. Nothing like a small (non-random) sample size to skew results. I think I could formulate a coherent theory of mental illness related to facial hair with a dozen or less carefully chosen subjects. And now I read (and realize) we have more than 5 senses. And the whole sight-sound-touch-taste-smell gimmick is down to the big A. I mean, it’s obvious to anyone who’s had a cold that taste and smell aren’t independant. And you can ‘feel’ when you are in a changing gravitational field, like an accellerating elevator. And there are others I hadn’t even thought of. We sense when we are hungry, or need to urinate. We know where our limbs are. NewScientist had an article naming 21. But my favourite is the Circadian Rhythm. Knowing when to get up. I think mine is broken.