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Comment Re:I want to see inexpensive plugin hybrids but .. (Score 1) 135

You might want to read up on how current hybrid vehicles actually work, 'cause it seems you have more than one misconception going on.

I have. For instance, my latest vehicle is the Ford F-159 XLT,, the full-hybrid model of the F-series pickup truck line. Power train is:
  - 6 cylinder dual-turbo engine. (runs low power but approoximately doubles output when a lot is needed.)
  - 47 HP motor-generator "pancake" on the engine side of the ttransmission, to scavenge / return power to./from a 1.5 kWhr lithium battery.
  - 10-speed automatic transmission, working with the lithium battery;s main alternator to fine-tune match the engine/mogen to the current driving situation. Max power of engine plus hybrid mogen; 430 hp.
  - full four wheel drive.

So it's primarily a gas-engine power train with an electric-car motor mechanically coupled to the engine shaft. Many other hybrids, from the venerable prius onward, are similar, with plug-in variants having a big scavaging/peaking battery good for pure electric operation of tens of miles rather than a minute or so and a wall-powered charger added.

What I'm looking for is essentially a pure electric - totally electronic "transmission" consisting of alternator(s) between the batteries and the motor(s), plus a tiny engine-generator able to burn gas and feed some teens of KW of charging power into the batteries when running down the road or parked near it.
 

Comment cobalt chemistry, not so nice. (Score 1) 115

Do the Waymo batteries use one of the lithium chemistries including cobalt, or a non-cobalt chemistry such as lithium iron phosphate?

Cobalt chemistries have a higher power/weight and energy/weight ratio, which made them the go-to chemistries for vehicle batteries. But they also produce oxygen when the cells overheat, leading to an unextinguishable runaway fire hazard: A burning cell makes enough heat to ignite the adjacent cells, so the whole assembly of them goes. Bad enough when it's a car's worth, but a disaster if it's a shipping-container sized module of a utility energy storage site. (And even worse when the site is a building full of racks, which someone had "protected" from fire with water-spraying, equipment-shorting system, so the whole site burns up, as happened recently with one in California creating a toxic mess.)

That's why purpose-built stationary lithium energy systems use non-cobalt chemistries - heavier, but a shorted cell just kills itself without getting hot enough to light off its neighbors.

Comment I want to see inexpensive plugin hybrids but ... (Score 1) 135

I want to see inexpensive plugin hybrids.

But not like the current ones, which are primarily an engine/tranny powertrain with a motor/generator + small battery for scavenging downhill/braking energy for later accelleration/uphill/cruise/power-boost.

I want ones that are primarily a battery-electric with a small aux engine-generator (say 15-20 HP range), big enough to power crusing with a bit left over for gradually charging. That would let you range-extend by the size of your gas tank plus fillups (i.e. indefinitely if only gas is available) or go from battery empty to back on the road in a couple tens of minutes.

The backup engine would only run at max-efficiency speed and could use an atkins-like cycle (see "liquid piston engine") to get the max power out of the fuel. Most operation would use power-grid charging (when available and cheaper than fuel).

Comment What a funny thing to say (Score 1, Informative) 86

What a funny thing to say about something that is literally all text. Match up the code itself with the commit message and the ticket that caused it to happen - we work in the most documented business there is.

If you don't force/write good commit messages then you get what you deserve.

If you don't force/use good issue tracking then you get what you deserve.

In general, AI now composes my commit messages. Then I delete 2/3 of it. Sometimes I'll touch it up a bit. So it is helping our process...

For every line of code in our repo I know who wrote it, when they wrote it, what they said about writing it, and why they started to write it in the first place. If you don't know those things then you (or your organization) are doing it wrong.

Comment Re:More accurate headline (Score 1) 129

For all we know, what looks to you like a one-day delay is actually a three-month delay, they just had a different launch scheduled the next day.

No. Launching a rocket is not like launching a plane. You have to get it to the platform and set it all up. You have to register with the feds. It's a whole thing. And here (well, at Vandenberg) there is just one SpaceX platform at the moment. I think they are talking about building another.

Maybe they can delay for a day, but at what cost? If your guesses are accurate that is.

You might be right and maybe I have absolutely no idea what I'm talking about. Here's the thing:
https://spaceflightnow.com/lau...

If you keep an eye on that site because you live 50 miles away and like to stand in your driveway to watch launches then you start to notice things. You see the schedule slip by 24 or 48 hours on about 25% of the launches. Sometimes done ahead of time and sometimes the same day (with notes about weather delay on the spaceflightnow page) and sometimes near the last second - as verifiable because the live webcast gets scrubbed with N seconds left on the clock while the camera watches the rocket getting fueled, etc.

I may be way off on the 25% number - it could be half that. It's not double. But it's really unusual for them to slip more than a day at a time.

These launches happen nearly once/week at this point. It's not hard to see the patterns. Sadly, I could not find a good record of how often they are pushed back - I suspect because it's just not a big deal to slip a day or two for these kinds of launches. Moonshots would be a very different story. Mars even more so. But there are 10K+ starlink satellites in orbit and they go 'round every 90 minutes. I suspect they could do 90 minute slips if it were not for all the actual work that goes into a launch and the time to figure it out and the federal paperwork, etc.

To me at least, launch windows makes more sense than just making non-retail employees work on a federal holiday.

Here's the other thing: Elon is an ass. You can ask pretty much any of his current or ex employees - including myself. He doesn't much care what holiday plans he's ruining.

Comment Re:More accurate headline (Score 1) 129

Launches slip *all the time*. I live about 50 miles from Vandenberg, so I keep an eye on when they go up to see if there's gonna be a good view. My guess is that about 25% of them slip - and when they do, mostly it's a 1 day slip.

So slipping to the next day can't be a big deal. Especially if you're planning it ahead of time. Unless you're pushing up against the next launch - which would be unusual.

Yes, there are windows for some satellites. But I think they are roughly daily with these.

Comment Re:Nope (Score 1) 82

Dude. I'm so old I have actually used a VT100. I actually used a teletype for a few minutes for the heck of it. No punch cards, though.

I'm pretty clear on what a terminal emulator is. I've probably used one more days than not over my more than half century.

My point was: **We're totally ditching github!!** - and yet their website still links only to source on github.

Comment Look up "human shields" (Score 1) 255

And a douche bag of a president who drops bombs next to schools and kills 135 kids . Should resign on the spot for that.

Look up "human shields", the practice of siting military targets among (or in or under) large collections of non-military civilians, in order to deter strikes against them or produce propaganda claims of atrocities when they're attacked anyhow.

In such situations the fault for the "collateral damage" is assigned to the side that set up the arrangement, not the side that hit it.

Nevertheless, it should be noted that the US has been trying very hard to use precision munitions and extreme military intelligence to take out military targets with as little harm to the innocents they're embedded among as possible, with impressive success. Compare the amount of collateral damage in this war to any of those conducted in the 20th century.

Comment Comparing your accent to claimed residence history (Score 1) 255

He's doing the bare minimum sniff test of verifying that *you* are the guy whose name is on the bookings and not someone sneaking in on someone else's name who can't even pronounce the name on your fake id.

At least in the case of people claiming to be returning citizens I've been told that they're comparing your accent to your claimed residence (or residence history).

Different words are acquired at different ages, and many are pronounced with regional variations. An expert can talk to you for a few minutes and come up with a pretty good age-map of where you lived as you grew up. An agent with a modicum of training can detect a mismatch between how you pronounce certain words and your claimed residence and pass you through quickly or keep you around and drill more deeply. (If you now live in an area with a regional accent wildly different from where you grew up it can help to answer a where-do-you-reside question with "Footown, but I grew up in Barstate".)

I presume they are doing something similar, though no doubt with lower resolution, on the world-wide level for visitors from other countries.

Comment Re:Silly politcal granstanding all around (Score 4, Insightful) 255

... Trump is a moron elected by a very vocal minority of idiots....

Yeah. I wish that were true. Trump was elected by a majority. And his current support numbers are still around 38%.
https://www.economist.com/inte...

It turns out the number of idiots if really high. And the ones running the country and enforcing the 'laws' include a lot of 'em.

I would much rather go nearly anywhere in Europe.

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