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Comment: Re:Good! (Score 1) 619

by timnbron (#47277789) Attached to: 2 US Senators Propose 12-Cent Gas Tax Increase

I'm actually surprised to find there are vehicles running on petrol there at all. New Zealand is tiny by American standards. You can't go 1000 miles in one direction without falling into the ocean from the furthest points, and in some places it's only 14 miles from coast-to-coast.

They have an extra tax per km for diesel which means it's roughly the same price for cars as petrol. Trucks are all diesel though.
Outside the city, there are very few decent motorways. The geography is quite complex. There are very few flat bits. And just outside the city there are plenty of gravel roads. They keep promising to tarmac them, but only a few km per year. Every year we have slumps and slips as the earth makes its way downhill. Most of the money gets spent on repairing them, and the big roading projects tend to favour the highways near the city.
It might be just over 1000 miles from end to end, but there's hills most of the way and a three hour ferry ride.

Comment: Re:Good! (Score 2) 619

by timnbron (#47277715) Attached to: 2 US Senators Propose 12-Cent Gas Tax Increase

$7.26 USD/gallon according to Google's latest exchange-rate thingy, but what is neglected is that New Zealand has at least four advantages that the US does not:

1) geographic size - infrastructure costs have to be orders of magnitude smaller.
2) smaller population, ergo less automobiles to pound on the aforementioned roads

Those two tend to cancel out. Yes, we've got less land area, but we've also got less people to pay for it. According to Wolfram Alpha, the population density in the US is double that of New Zealand.

3) the population is mostly concentrated in a couple of cities, and not of a huge relative geographical area. More folks can do mass transit there, and drive less often.

I wish. There is actually a substantial number scattered all over the country. The land was divided recently, so everyone got their block, which got divided several times for their children. One of the big hazards when driving is the numerous driveways everywhere. So cars became the norm. Public transport is good in the city, but it's certainly not mass transit. Outside the city there are a few bus routes, once an hour. Trains (outside the city) are for tourists. The only passenger trains we get here are for the annual steam run.
I wish we'd get serious about railways. We seem to treat them as buses on rails, going 40mph tops and winding all round the suburbs. It's very difficult to get around here without a car. I'd love to use my bicycle, but there are big hills in every direction, and that seems to be the norm here!

4) an immigration policy that would get us called Nazis if we implemented them here (see also the current immigration woes and their contribution to economic issues here in the US)

We have more Chinese than Maori. Didn't seem to stop them!

Comment: Re:Yes we can! (Score 0) 210

by timnbron (#38363544) Attached to: LHC Homes In On Possible Higgs Boson Around 126GeV

I somehow never got this point. In the standard model, you're starting from a Lagrangian formulation of a quantum field theory, so the existence of a scalar product in the Hilbert space spanned by the theory automatically guarantees normalization of probabilities, no matter which physical values you attach to the parameters of your model. So if you're getting something larger than one, you must have made an error somewhere on the way, but that doesn't imply your entire model is wrong.

... I somehow never got this point...

Comment: Re:heat (Score 1) 132

by timnbron (#38008220) Attached to: NASA Creates Super-Black Carbon Nanotube Coating

The infra red space telescopes are positioned out of the sun ('behind' the earth) in order to keep cool. However, there's still the heat from the electronics, and there's no way to get rid of that apart from by radiating the heat away. Black radiates well, hence colouring it black will keep the spacecraft cool.

In sunlight, more heat is coming in than going out, hence black cars get hot, and normal spacecraft are coloured silver (or similar) to make them highly reflective and bounce the heat off. (Even those spacecraft will often have dark surfaces on the other side in order to keep cool.)

I'm guessing that the Blackbird SR-71 got so hot with the engines, that painting it black would result in far more heat radiated than the sun would put back in. It's all a matter of balancing heat in and heat out.

The summary is a little wrong: "Because the light absorption level is so high, the super-black material will also keep temperatures down for the instruments it is used on." I think that should be "Because the heat radiation level is so high, the super-black material will also keep temperatures down for the instruments it is used on."

Comment: Re:Highly Suspect (Score 2) 462

by timnbron (#37634024) Attached to: Ohio Supreme Court Drawn Into Magnetic Homes Case

I did an experiment years ago on a 5 inch floppy disk and a fridge magnet. I had to put the magnet in direct contact with the disk surface itself before I got any corruption. If it took that much on a 1980s floppy, it must surely take much more on a shielded and enclosed hard drive.

Cathode ray tubes certainly. Used to have lots of fun making the screen change colour, until my parents got upset. But it would still take a very strong field even for that.

Comment: Re:Radioactive packaging (Score 1) 277

by timnbron (#32687072) Attached to: Tracking Down a Single-Bit RAM Error

Very interesting. We had a problem in telephone exchanges about 25 years ago. All data was held in memory - no disk drives (except for billing records I recall). Some little old granny would mysteriously acquire a premium service. It only affected the lines that were hardly ever used. It was tracked down to "alpha particle corruption", which gradually eroded the charge, which effectively flipped the bit to a 1 and gave the subscriber a random service.

Don't know any more than that, but the old hand that described it to me, did so with unusual glee...

Make sure your code does nothing gracefully.