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Comment Re:Starbucks (Score 1) 294

Milk is a reasonable component of a tasty coffee drink.

The fats in the milk bind with the bitter acids, changing the nature and taste of both. People that add regular milk or cream often prefer a stronger and therefore more bitter brew because the bitterness is mellowed while the tastes they prefer remain strong.

This effect is well known with wine. Red wines heavy on tannic acid are paired with fatty foods, especially fatty meat and cheese. But the "in" thing in the coffee world is to have a very strong brew with nothing added.

Don't assume that your biases or tastes are correct, or will even remain the same. My wife used to complain about how I was ruining the coffee by adding milk. After she became pregnant her taste changed to prefer milk and eventually cream in her coffee.

Comment Re:Why don't they... (Score 1) 311

The current they produce is trivial, just enough to keep up with the self-discharge of a new car battery and the light car-off load (usual spec -- under 40mA, with under 20mA the design goal). It's not even enough to keep up with the self-discharge of an older battery.

An EV has on the order of 100x the battery capacity. The self discharge rate isn't quite as high, but even 50x the area of that battery maintaining solar cell isn't feasible. And that would just keep up, not really add charge.

Comment Re:Environmental Impact? (Score 1) 311

All matter is "recyclable". But most things are not recycled.

Automotive and larger lead-acid batteries are among the most completely recycled items. That's because they have a simple, easily separated structure. Once shredded, the metal plates are trivially separated from the plastic. Sometimes by simply floating away in the rinse water that dilutes the acid. The lead-antimony is melted off any support grid at low temperature, then the grid is melted down at high temperature. After reduction and slag removal, the still-molten lead alloy can be directly cast as new grids. The battery cases are molded with a higher percentage of virgin PE, but excess scrap is still usable in other plastic products.

You could pretty much do that in your backyard.

Now, how do you recycle LiFePO4 batteries (or any lithium chemistry)? Would any part of the recovered material be acceptable as an input to make new batteries? If we can't do it today, why believe that a recycling process is feasible?

Comment Re:Why can't they extend the range? (Score 1) 311

Rapid acceleration is a prominent advertised feature of electric because it's relative easy. Better performance comes along almost automatically once you put enough batteries in to get acceptable range, with impressive performance when you have reasonable range.

If you keep the battery structure the same, doubling the range also doubles the available instantaneous power from the battery. And electric motors are mostly thermally limited -- you can put 10x or 20x the continuous current into a small motor for a few seconds, until the wires melt (really until the resin bonding the coils starts to break down). This combination means that even a slow car with short range can feel like a muscle car for a few seconds.

Of course you can go too far. We bought a used motor for our EV project that had (undisclosed) spun the rotor on the shaft. Now that it was loose, it would slip again under load when hot. Based on the length and diameter of the press fit section of the shaft it was putting out many hundreds of horsepower when it broke loose the first time.

Comment Re:just miss out the occasional numbers (Score 1) 330

Serial numbers derived from a vehicle master serial number sounds reasonable, until you hit real life.

Road wheels on tanks had a fairly short life between rebuilds, so the serial numbers would be quickly mixed up. And besides, explicitly transmitting the production information to every factory producing parts would be a huge, obvious security risk.

Yes, the Germans could have easily scrambled any specific serial number if they knew this was happening. But changing production to scramble or eliminate every serial number would have been almost impossible. Just keeping production active was almost impossible, when they couldn't predict which factories and parts shipments would be lost overnight.

Comment Re:Nope, not kidding. (Score 1) 2058

I've kayaked in the Yukon.

About 3/4 of the population lives in Whitehorse, which is a still a small town.

Only two or three other villages have more than 1000 people. And they are counting people that are a few miles from a road.

When the population and population density is that low, the only feasible approach is to accept that preventing fires, keeping them from spreading, and getting people out is the only approach for most of the area.

And with a population that low, they aren't going to be paying their own way. The territory is like an empty woodland lot. It's value is in its future use and the natural resources that may be discovered.

Comment Re:NAT is good (Score 1) 583

That surprises me a bit.

Knowing Comcast and similar ISPs, I expected being assigned a single IPv6 address, with an extra fee for every additional address.

Many here might not remember, but in the 1990s ISP contracts usually specified that a residential / small business connection was for a single machine. You had to upgrade to a more expensive contract to use multiple machines at once. Linux led the way with cheaply available NAT, and it was initially banned as being against the terms of service by many ISPs. Not that they could do much about NAT -- it's difficult to do NAT detection, and at the time those were the customers you didn't want to lose.

NAT only became widespread when it was pre-configured into small routers. At that point it was too late for ISPs to do much about it.

If the software had the support at the time, I'm certain ISPs would have allocated a narrow port range instead of a whole IP address. Even back when there were plenty of IPv4 addresses.

Comment Re:What the industry refuses to admit (Score 2, Interesting) 277

And of course there is economic value to "piracy": advertising and lock-in.

Microsoft's lock on the market happened because of illicit, unauthorized and implicitly authorized copies. Their resulting monopoly position has been worth vastly more than any revenue foregone or lost.

Even if a software publisher doesn't end up with a monopoly, no-cost copies can create a viable market size where none existed before.

There have been serious economic analyses that suggest the market has a below-optimal illicit copying ratio. Yes, overall productivity and software/service revenue would both be higher with more relaxed rules and actions. I have a much more of a level playing field / follow-the-rules attitude, but bogus press releases like these push me away from that viewpoint. Bogus, biased "studies" leave me opposed to anything that such organization want -- if it's the best they could come up with, they are definitely wrong.

Comment Cost of painting a car: far more than $400 (Score 1) 390

$400 will get you taxi-quality paint job. You'll get a single stage (non-clearcoat), not very durable layer of paint over everything. You'll be lucky if they don't paint over the tires and windows.

A repaint like that will hurt the resale value of most cars rather than help it. It's only slightly better than mismatched body panels and heavy rust.

A presentable paint job costs about $2000, and that doesn't include door frames, trunk interior and engine compartment.

Comment Flash light -- name origins (Score 1) 271

The word "flashlight" was actually a derogatory term. The carbon-zinc batteries developed insulating bubbles under high load, and the light flickered and flashed. I'm sure most readers here have experienced this -- imagine how bad it was when the technology was new and barely understood.

That said, I have to agree: torches are what the mob from the village carries when they come to break down the door of your lab.

Comment Build WHAT in California? (Score 1) 619

Build WHAT?!

Not in California. Not even if the central valley is a dust bowl to save the river smelt. Not even if the state paid the highest electric rates in the nation due to horribly botched deregulation. Not even if the manufactured crisis was easy to trigger because the total electric power available is very close to peak usage.

And yes, if California seceded from the Union, the only liquid flowing in most of California would be untreated sewage and contaminated field run-off. Water quality regulations are only important when they impact voters.

Comment NJ nicknames (Score 2, Insightful) 240

I think that some people do not know why NJ is called "the armpit of America". It's not just the smell of its refineries and chemical plants along the coast. Look at its position on the map.

Most visitors just see the part of NJ along I95, missing the sections further inland which gave it the name "The Garden State".

Comment Re:G-forces ???? (Score 1) 384

Hitting escape velocity won't help -- whatever is sent out will be unrecoverable. It will roughly be on Earth's orbit around the Sun, but likely won't coincide.

There is some flexibility by shooting the object past the moon, and getting a little bit of a 'slingshot' effect to modify the resulting orbit. But it would still require steering rockets because even a slight error in the initial path or orbital calculation would make a huge different in the resulting orbit.

This topic would make for a great physics and geometry lesson. Why inertial orbits starting from the surface always intersect the surface (the original topic). Why going from a one-body system to a two-body system might be able to change this, but at the expense of extreme sensitivity. How the complexity of potential orbits vastly increases as you add more bodies.

Even more interesting, is the extreme state sensitivity of the "interesting" configurations. A few seconds of arc difference in the initial course can put you someplace completely different. Simple orbital calculations assume point sources of gravity. That's not a bad approximation if you are far enough away, but a "slingshot" breaks that assumption. You can't even model the objects as uniform spheres -- the earth isn't spherical, and it doesn't have a uniform mass distribution. And for objects such as the Earth that have significant magnetic fields, there will be a deflection on approach and departure.

Bottom line is that anything done in space requires a significant ability to steer, and most operations require the ability to dynamically navigate.

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