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Comment Hardly devastating, but a waste of several hours (Score 5, Insightful) 157 157

Program crashing at startup? Okay, let's add debugging statements.

Can't get the debugging statements to execute? Okay, let's try removing code.

Doesn't fix the problem? Okay, let's keep removing more... and more...

A couple hours later, so much code was removed that the entire program had become nothing more than an empty main function that still crashed. This led to the following rule which I try to follow to this day: Make sure that you're actually compiling and executing the same copy of the code that you're modifying. ;)

Comment Re:Physics? (Score 1) 178 178

This is all wild speculation, of course. My actual guess is it's some phase change different from what's commonly used in PCM. They've specifically stated it's not PCM, memristors, or filaments. That honestly doesn't leave too many semiconductor transitions for it to be. It leaves even fewer that would be non-volatile in the absence of a maintenance voltage. Maybe it changes crystalline structure from one form to another or changes crystal alignment without ever becoming fully liquid or gaseous.

Comment Re:wft ever dude! (Score 1) 210 210

One of the design goals of IPv6 was to simplfy the routing logic so we could make faster and cheaper hardware. That's why there is no more IP fragmentation for example. Making the fields variable size defeats that. It's much easier to build hardware for fixed field sizes.

Plus you can't project exponential growth out to infinity. It is inevitable that some factor will come to limit the growth. It has been really incredible how long transistors have maintained their growth, but even that seems to be coming to an end.

Also, we're probably not going to have a 64->128 bit transition. Not without a fundamental change in the way we do computing.

Comment Re:Why go without GPS? (Score 1) 30 30

Indeed, Titan the easiest large world to explore by drone, so long as they tolerate the cryogenic conditions. A highly efficient version could potentially fly continuously just on RTG power (there have been proposals along these lines), although anything adapted to deal with the added weight / inefficiency of hardware to carefully land, collect samples, carry them, etc would probably have to use flight batteries.

Comment Re: Truck Stops, Gas Stations, etc (Score 1) 879 879

I called you daft for not understanding the concept that someone who runs a swapping service station covers all costs related to their business activities and rolls them into what they charge for service, just like every other business does. I fail to see what is hard about this for you to understand. The answer to "who pays for X cost" is *always* "the service provider, with the costs indirectly passed on to their customers via the rate charged".

Really, you think that bad fuel can't damage an engine? It can and does. And it's the supplier who ultimately bears the cost. No, "bad electricity" is not a proper analogy (although your sarcasm in this regard is funny given how many devices are damaged by surges every year); a gas station fuels vehicles by insertung fuel into them, while a swapping station fuels vehicles by inserting pre-charged batteries into them. Batteries correspond to fuel in this context.

In what world do you live where car parts are regularly inspected by the manufacturer after being installed into the vehicle? Cars have hundreds if not thousands of parts more safety critical than a battery pack, and yes, manufacturers *are* liable if their failure modes due to damage pose an unreasonable risk of injury. Think of a famous failure case - say, for example, the Ford Pinto fires. Were the gas tanks defective? Nope. But the cars had an unacceptably bad failure mode in certain types of crashes, and it fell on the manufacturer to fix it - as it always does. A part must meet its use case, and if its use case is "deliver electricity from a swappable system and not burn the vehicle down if damaged", it has to contain the necessary safety systems to do that.

Lastly, you're still stuck in bizarro world where ICE vehicles full of combustible fuel are incombustible, whereas EVs with no combustable fuel and more often than not with batteries less flammable than a block of cheese (once again: *not all li-ions are the same*!) burst into flames left and right. Meanwhile, in the reality that the rest of us live in, the opposite is true. Heck, last summer I saw a flaming hulk of a passenger car with fire crews trying to put it out to extract the burned bodies of the two tourists who had been driving it. Meanwhile, Teslas and Leafs have been in many wrecks - go to Google Images and search for "crash tesla" or "crash leaf". Where are the fires from these oh-so-flammable vehicles? Yes, they have happened, but at a much lower per-vehicle rate than gasoline cars according to NTSB stats. Sorry, but your fire conceptions are just not based in reality.

Comment Re:Passed data with a ton of noise? (Score 4, Interesting) 369 369

They did it because that's how the company that makes the cables describes their test environment. They claim "clear unmistakeable" improvements in the audio quality in the setup Ars used, but only if you plug the cable in in the correct direction (denoted by an arrow on the connectors).

In fact the company claims that they determine which way to face the arrow by plugging the cable in and listening in both directions and choosing the best.

Comment Re:quickly to be followed by self-driving cars (Score 1) 879 879

Do you want the seats front facing or rear facing? 10-30lb or 20-50lb? Even then you're going to have to adjust it for your kid, and figure out what sort of bizarre adjustment scheme this particular seat uses. On some seats you have to take them apart to adjust past certain points. Uh oh, the kid always wants to sit behind the driver and the seat is installed on the passenger side.

Who is going to install and remove the seats every time someone calls for one? Are they going to have liability insurance in case they accidentally install a seat improperly and a kid is injured or dies?

And then the parents have to go back and make sure the seat is clean once they're done with the car. Kids are amazing at finding ways of making messes when you least expect it.

I think "have young kids" is one of the ares where the "car as a service" concept does not work. Not unless you drive only very rarely with the kids.

Comment Re:Why go without GPS? (Score 2) 30 30

On the Moon or Mars they wouldn't reach very far. But a RTG-powered version on Titan would have unlimited range (although may need to land periodically to recharge its flight batteries). And even a rocket or gas jet version would have quite significant range on an asteroid.

Such a design is obviously going to be very mission sensitive, hence the need for different propulsion systems. Some missions would benefit significantly as well from wings to allow for long distance flight on bodies with atmospheres (Venus, Titan, maybe Mars, etc). A couple worlds, such as Titan, might benefit from landing floats. And so forth. But that's where rapid prototyping tech (such as 3d printing) becomes useful - they engineer the base model and then can play around with variants with ease. Hopefully in the end they'll have a sample collector module with a workable version for almost any body in the solar system. And for the interests of science, we really need something like that, a universal adaptable drone module - to be paired with a universal adaptable ion tug module, one of a couple variants of a universal adaptable reentry / landing modules, and the same for adaptable ascent modules.

It's impressive what science can be pulled off on the surface of another world. But it's nothing compared to what we can do here on Earth with a sample return.

Comment Re:Truck Stops, Gas Stations, etc (Score 1) 879 879

In one truck, yes. The frequency of dead batteries, however, will be the same as passenger vehicles; who will dispose of those?

Seriously, you can't be this daft. The operator, of course, with the price rolled into the service cost.

All of which are relatively involved.

No, they're not. Even your laptop battery estimates its capacity, and that's about as simple as li-ion battery packs get. Coulomb counting, voltage measurements at start and end compared to the charge temperature, charge voltage curve shapes, direct measurement of pack heating over the course of charge to measure internal resistance, and about half a dozen other methods are all usable and widely used to estimate capacity remaining in a pack. Pretty much every modern EV and hybrid in existence checks its battery pack's performance at least at the pack level, if not the individual cell level (Tesla does it at the "brick" level), to see how it's aging and when components or the pack as the whole need to be replaced.

Measuring remaining battery capacity is a concept older than the light bulb.

testing and inspecting a battery for damage and danger conditions so you don't install it into someone's vehicle and get a lawsuit for "vehicle exploded in a giant flaming blaze" (or drive all your customers away with "we don't test our batteries for anything but charge, and damaged batteries may set your truck on fire") is wholly different.

Just like gas stations check their gas for impurities that can cause damage to an engine? No, it's the manufacturer's issue to ensure that the product meets its stated usage specs - in this case, the specs including safe handling of damage and X number of swap cycles. Meeting damage control specs is why Tesla isolates each cell in a canister to prevent failure propagation. And why packs always come with fuses/breakers that blow when the pack gets wet or there's otherwise a short.

(Just ignoring that many types of li-ions don't burn even when abused. Tesla uses standard cobalt-based 18660s, which is why they have to have a failure isolation system, but vehicles like the Volt and Leaf use more stable spinel chemistries)

That may result in diesel being the cheaper fuel by far

Tesla's battery packs have an 8 year, unlimited-mile warranty. Even if we assume that they're only good for 1000 full charge cycles (which should be well on the low end), at 30 tonne-miles per kWh of charge, times 1000 cycles, and $150/kWh for the pack, that's 200 tonne-miles per dollar of pack capital cost. A diesel truck will get about 120 tonne-miles per gallon of diesel, and diesel costs somewhere in the ballpark of 6x more than electricity per unit range (depends on your location), meaning that the electric version saves about 3-4$ per dollars of energy cost per dollar of pack capital cost.

There are a lot more batteries on a truck.

Wait, so you're picturing them being done individually, one after the next? Seriously? *smacks forehead*

Fortunately, if you mount batteries under there without a bunch of armored doors and other shit to hold it all together, the cargo container catches fire when the batteries become damaged.

In the parallel world where EVs are always catching on fire, and petroleum-fueled vehicles aren't - quite unlike our actual world.

Comment Re:First note to the PAs on the new show: (Score 4, Interesting) 205 205

You know, that would be the best prank ever. Convincing Clarkson that he's getting a new TV show but having the actual point being to secretly film him when he's not acting for the fake "show", as they subject him to situations that would be increasingly uncomfortable for a speed-obsessed labour-hating hot-headed racist diva. Sort of "Top Gear" crossed with "An Idiot Abroad". ;)

"Anyone attempting to generate random numbers by deterministic means is, of course, living in a state of sin." -- John Von Neumann

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