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Comment Re:DC power? (Score 1) 236 236

Here are two reasons why AC is generally better than DC at consumer level:

1: AC arcs are self-extinguishing every half cycle.

Anecedotally: Back in the days when Sydney Australia had 250VDC distributed in industrial areas as well as AC, a DC-powered lamp in a factory blew (filament failure) and started arcing internally. That arc eroded away the glass stem of the bulb, its base, the ceramic bulbholder and most of the flex leading back to the ceiling rose before someone managed to kill the power.

2: Human safety:

DC is more deadly than AC, for pragmatic reasons: If you get attached to a DC power line for any reason, continual muscle contraction will ensure you cannot free yourself. With AC, the pulsating nature of the beast has a greater chance of making you kick yourself free.

I've known people who've been bitten by high voltage DC, AC and RF feeds. The DC guys came off worse than AC, but RF can cook you.

#1 means that every single piece of switching equipment in a DC circuit needs to be derated over its AC counterpart. Take a look at any switch you can lay your hands on and you'll notice that there are AC and DC ratings. This is down to arc resistance, not current carrying capability.

Comment Depends how its done. (Score 1) 293 293

Led lighting can be dimmed down to 30% (or less) and snap up to full brightness when someone walks underneath it. The better luminaires all communicate with each other, so that a car will cause them to light up several poles ahead whilst a walker will only light things up 1 or 2 ahead.

This system is being used extensively in the Netherlands and in _some_ UK areas. The initial cost is far outweighed by power reductions and labour costs (lamp changes) being eliminated - the cost of changing a lamp far outweighs the cost of the lamp itself.

Unfortunately, the UK is the home of the most amazing amounts of Jobsworthian behaviour. Council bureaucrats are deliberately electing to switch off lamps despite safety warnings and justifying this to councillors (who are mostly non-technical) by claiming that it's the only way possible, deliberately withholding knowledge of these systems from those decisionmakers.

I have pointed a few councillors at these systems. They're generally angry about not being informed of their existence.

These are the same UK councils who repeatedly raise parking charges in shopping areas and then wonder why small businesses are suffering as drivers go to retail parks or malls instead - they keep justifying the raises on the basis of "parking income is falling".

Comment Re:FORD (Score 1) 269 269

Older analog car radios often had a push on/off switch integrated behind the volume knob, or the older style "turn down to zero and it clicks off" inherited off cheap transistor radios.

I've driven cars with both (Datsun B210 had the former, Volvo 440 the latter.)

My current car (Nissan primera) turns on the radio if you tap the volume knob and has a separate "radio off" button. The ergonomics of the N-form condole are well thought out.

Comment Note what he wasn't charged with. (Score 1) 1173 1173

No criminal damage, no theft, nothing related to the confrontation with the drone owner.

Discharging a firearm within the city limits (not at a range) is a stupid thing to do regardless of the circumstances. What goes up, must come down - and stray bullets are a major source of death and injury in the USA thanks to feckless gun owners who take no account of trajectories before pulling the trigger.

I know shotguns use pellets but being rained on with birdshot still isn't nice and it can damage paintwork on cars, etc. Buckshot still has enough kinetic energy on the way down to cause substantial injuries at a couple of hundred feet

Had he used a butterfly net, I think the police would have left him alone.

Comment Re:Blimey (Score 1) 509 509

You're perfectly correct that MSRs don't actually run on Thorium. That's one of the reasons they'd be an effective nuclear waste burner.

The advantage that MSRs have over pellet/pebble/rod-based reactors is that when you throttle down, an excess of xenon-135 builds up. This is a neutron poison and damps down the reaction, making it hard to throttle up again until it's decayed (that takes a while. The Half-life is 9.2 hours). Attempting to push through the xenon poisoning by setting the power to 11 can be catastrophic - this is what took out Chernobyl. http://hyperphysics.phy-astr.g...

Because the fuel is not sealed into capsules in a MSR, the Xenon can be extracted into the thermal expansion headspace just before the circulation pump by sparging it (https://en.wikipedia.org/wiki/Sparging_(chemistry)). You need to do this to get helium and other gasses out anyway so it's not a big deal. The end result is that throttling is fully linear and because MSRs don't suffer from steam voids if you snap to full power, the reaction rate can track load at least as fast as a hydro plant and probably as fast as a OCGT plant.

I was going to write a lot more but given this is about space applications it's probably irrelevant. You'll need a thorium blankie for your U233 MSR reactor or you'll run out of fuel eventually. Having it soak up stray neutrons is a good thing in what would probably be a relatively confined space.

Comment Re:Country run by oil barons does nothing!!! (Score 1) 195 195

"Advances in uranium mining made it substantially cheaper to mine and refine fresh fuel than reprocess "spent" fuel."

Reprocessing fuel rods allows extraction of bomb-making materials. As such, it's a highly controlled process (political and military) and the USA + Russia both offer subsidised uranium as reactor fuel to try and discourage countries from developing their own reprocessing or enrichment systems.

Fun factoid: Iran has several hundred kilos of 40% (or more) enriched U235 squirreled away as reactor starter material. Even Mossad have reported that they don't believe they're working on bombs, as they'd have already demonstrated one if they were.

Comment Re:This is outrageous (Score 1) 274 274

"For that matter, the continued dominance of middleman organisations like movie studios, book publishers and record labels is arguably the biggest problem with the creative industries right now. "

It is those middlemen who are the ones lobbying for these laws. They freely rip off everyone in sight and feel themselves to be above the law.

The _entire_ Hollywood movie industry is worth less than Microsoft even in its diminished state. It's an idle fantasy, but one of the the things companies like Google could do to kill the relentless litigation is simply _buy_ the companies involved with money found down the back of the sofa.

Comment Re:This is outrageous (Score 1) 274 274

" But professional copyright infringement, where you're actively ripping off works for substantial profit, can be a criminal matter, punishable in criminal courts with fines and jail time. "

I look forward to seeing various music company executives in the dock. The well-documented systemic copyright abuse perpetrated by these companies against individuals, as well as standover tactics against "creatives" essentially forcing them to hand over their entire intellectual property portfolios with no or negligible recompense vastly dwarfs any other kind of copyright infringement that exists.

The reality, despite whatever you may _think_ it is, is that these laws are vastly disproportionate and mostly used by media companies to justify hiring City of London Police to go and kick in doors at the other end of the country in a blaze of publicity, with newspapers or TV illegally invited along - with charges quietly dropped a few days later when the Crown Prosecution Service points out the raids weren't legal, the charges won't stick and the recipient of the dawn raid probably has justification for substantial claims against the COLP and the companies which hired them, if he can afford a lawyer.

Comment Re:This is outrageous (Score 1) 274 274

"These penalties are the ones aimed at criminal copyright infringement. "

Which means whatever those prosecuting want it to mean.

The most blatant and widespread copyright violations are perpetuated by media companies against individuals in any case. Good luck getting a company officer jailed as a result.

Comment Re:This is outrageous (Score 2) 274 274

"Stop giving them any more wealth. Don't buy..."

This is happening in spades. Numbers are in constant decline.

Media companies try to paint this decline as proof that there is mass piracy going on, rather than admit they're not producing prodict that people want to buy - and the US + UK governments are falling for it, passing laws to prop up these companies, in the same way they tried to prop up their car industries rather than admit they were simply not producing what customers wanted.

Comment Re:This is outrageous (Score 1) 274 274

"Thus there's no place for actual creative people in this "industry" now. It's only for rentier who want to establish another aristocratic class."

Rent-seekers moved into the music and movie industries almost as soon as they were created.

What's happened since then is that they've become more blatent and more brazen about what they do and having exhausted all possible income streams from artists and buyers(*), faced with widespread consumer resistance, they are now doing everything they can to scare people into paying for product.

The real effect is more likely to be faced with a choice of paying for something they might have listened to but wouldn't pay for, most consumers will simply shrug their shoulders and walk away. The cartels will use the inevitable plummetting sales as further justification for claims that mass piracy must be taking place and push for even more draconian laws.

(*)recording sales were already declining when CDs came along, bubbled for a while as people rebuilt their libraries in new format and were already falling away again before fileswapping mp3s was common

Comment Re:Confused (Score 1) 274 274

"I agree that artists deserve some kind of compensation"

In the current environment, about 1 in 1 million artists do. The rest end up being burned and in debt.

Recording labels hate the Internet and the fact that it's forced them to bring their back-catalogs online. That's far less profitable than selling umpteen million copies of the latest formulaic pap, along with a few tried-and-true classics to pad out the shelves.

Comment Re:Just a thought (Score 1) 274 274

"For instance, you copy a CD that retails for $19.95, you get fined $39.40 which goes to the injured party"

When artists are writing newspaper stories pointing out that labels make money and artists end up with nothing more often in not, in major debt), who is the more injured party?

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