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Comment Re:They made the blocks into wheels (Score 1) 202

Or grooves would work maybe? If you had your rope as one large loop you could wrap it around the whole block a couple of times and then pull the rope from the top - the tension in the rope should hold the cradles in place and you can just pull continuously on the rope to move the blocks. If you were being really clever you could presumably put a second smaller roller in front with the same setup repeated to gain some mechanical advantage.

Comment Re: user error (Score 5, Informative) 710

They do have smaller gallons though: 31 US MPG is actually 37 UK MPG, which is not too bad for a 525 - beats my 99 2.8 A4 which does 30 most of the time (but then I use it very rarely, so I accept the cost of fuel as the trade off for having a very nice car for very little money as most people don't want something that thirsty).

The 320d is a wonderful machine - my partners 05 one does around 47 with some relatively leaden-footed motorway driving - could get it to 50+ with some caution.

Comment Re:Who would have guessed? (Score 1) 217

There's an awful lot of stuff you could make from plants that isn't exactly 'friendly' if used in high enough quantity or concentration. Reduction ad absurdum: Crude oil is simply the remains of zooplankton and algae after heat and pressure has been applied for some time... would you spray a field with it? Just because it's from a 'natural' source doesn't mean it's harmless.

Comment Re:If not... (Score 1) 865

In a modern car with fuel injection and electronic ignition? The kill switch can kill a number of components quite easily to stop the engine. Just using !kill as an enable to the signals that tell the injectors to open would be enough. For redundancy you could also make sure that the low-voltage side of the ignition coils is masked with it. For complete safety you can block the fuel pumps as well.

Comment Re:Not a surprise (Score 1) 303

The guy in the book showed you can mitigate the effect by measuring the delays and making sure your order hits all the exchanges it's going to at the same time. Cost is a few reels of fibre (or maybe, if you were being fancy, some kind of controllable TCP delay insertion hardware). These fund managers make quite a bit of cash: I'd hope they'd try to understand the game they're playing, instead of hoping that things work the way they've assumed they do and complaining when they're wrong.

Comment Re:Not a surprise (Score 1) 303

You have multiple separate exchanges. It's not about routing, it's about delays to _separate_ venues. By watching what happens on one you make plays on the other. An article I read somewhere (I can't remember where, so please forgive woolly statement) had the HFT traders making a profit on just over 50% of the trades, they just make a _lot_ of trades is all.

Comment Re:What's the problem? (Score 1) 1198

Hypothetical: A person is is of the opinion that someone must die. Perhaps this someone has committed an act so heinous that the person in question feels they should no longer be allowed to live. Why should that person not kill them? Is killing someone so abhorrent worse than allowing them to live?

Comment Re:Fucking Casuals. (Score 1) 303

But they're those long term investors everyone wants in the market right? They're expecting to make more than those few pennies on the stocks aren't they?

This fantasy long term investor looks at things they could invest in, determines the potential return and risk of losses and picks stocks to invest in. So when placing the orders to buy these investments they set a price at which they thing it's worth buying - e.g. where their calculated risk/return ratio favours that investment over something else. If someone winds the price up, exceeding the limit, then don't buy it, buy the other thing.

If you're not going to adapt to the market that you're in - e.g. make use of the information provided - like the fact that there are HFT players out there - you're pretty much asking to lose money.

Comment Re:Not a surprise (Score 5, Informative) 303

Nope. The 'scam' in the flash boys (from the interviews - as per usual Slashdot expectations I haven't read the book) is that someone places a very large stock order for X at the current ask price that is routed to multiple markets. Let's call them A, B and C. From your trader the delays to those markets are 10ms, 100ms and 200ms respectively (which are ridiculously high numbers for this game). Your HFT trader has collocated servers at markets A,B,C, and minimal-latency links between their servers. So when the order arrives on market A and fills, they think 'Hmm, someone is looking for a shedload of X. They then place instructions to buy on the other markets, followed by orders to sell at a slightly increased price. They have 90ms (- the time for exchange A to match, fill, post market data etc., and the time for orders to be placed on other exchanges). It's like some slow moving person walking from stall to stall in a (physical) market buying all the oranges, and announcing loudly that they are doing so. Is it illegal to run to the next stalls, buying all the oranges and then offering them back to the slow moving guy?

All the information is public. The market data feeds are available to anyone. You pay for more up to date market data (which includes details of fills, not orders placed) - you don't pay for the 20-minute delayed stuff on google/yahoo, but you do if you want it faster. You pay for collocation. You pay for those low-latency connections. You used to pay for a trading desk on the stock exchange floor, guys in coloured blazers who could calculate and make decisions faster. The system has never been 'fair', but HFT doesn't necessarily make it worse.

Comment Re:When you have a bad driver ... (Score 1) 961

If you are a super-duper-uber driver. Otherwise it's better at keeping the wheels turning at just below the point of locking up, which is where the maximum traction is. Hence why they used to teach cadence braking. Once you've locked the wheels the coefficient of friction is lower - and therefore braking distance longer - than when the wheels are just about to lock up. The big advantage is that with ABS every driver can mash pedal and stop in very nearly the same optimal distance as the 'best' drivers, and still be able to steer as well.

Comment Re:Happily parked? (Score 4, Informative) 293

Happened when I was at primary school. Something shorted out and started a fire and burnt several cars.

IIRC E36 BMW coupes caught fire occasionally because the cabling into the boot(trunk) lid would get brittle over time and split when it was flexed. In mine it manifested itself as the central locking failing because some wires shorted out. I'd imagine there's a sensor for the alarm, or supply for the central locking that's live even with the ignition off, so it's not a big leap of faith to see that a parked car could catch fire due to something shorting out.

Cars have quite a lot of 'live' when off electrical equipment - cooling fans for example - that can be on at any time, so faulty or ill designed wiring could cause problems in stationary cars.

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