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Comment Cute Little Aluminum Blocks with Turbochargers (Score 4, Interesting) 248

My 2.2 tonnne Ford 4wd gets 25 mpg. My 1 tonne Ford Escort (1973) got .... 25mpg. Your mate is wrong. When I first got a company car it did 12 l/100km. 25 years later the same model of car was grtiing less than 9, despite 25% more par, and meeting tighter emissions regs. Your mate is wrong.

You're clearly not talking about American cars. What's a 1-tonne Ford Escort? I did have a 1983 Dodge Ram D150 half-ton pickup truck with a Slant-6 and an A-833 manual transmission; that thing would get 25MPG and hold 75MPH all the way westbound across Michigan... of course, it took it a while to get to 75MPH, merging was just like driving a Peterbilt with a 53' trailer full of anvils. That exact same engine and a comparable transmission were available for the Dodge Trucks line from 1960 to 1987 and was renowned for durability and reliability.

The key point is that Americans typically don't want them. To this day, in Canada, gasoline is cheaper than water. I'm not sure if that's a statement about gas prices or a slam against the sort of fool who feels the need to buy their tapwater in PET bottles, but I digress. So people buy horsepower. People buy large vehicles based on truck platforms.

As CAFE forces vehicles to become more fuel efficient - without addressing the underlying consumer demand problem! - manufacturers are being forced to use smaller and smaller engines. This means adding turbochargers to cute little aluminum blocks, narrower cam lobes and variable displacement oil pumps and smaller oil control rings all to reduce the internal drag, and thinner oils which offer zero cushion on connecting rod bearings. All of this gets stuffed into a full-size pickup truck with a trailer hitch. They're intolerant of real-world conditions and use, and because of their complexity they're expensive to repair. These vehicles will not have a long lifespan - sure, you might get a good fleet average mileage, but if 50% of the vehicles don't make it to the 100,000 mile mark, they're getting replaced faster with all the environmental damage of producing and disposing of the vehicle.

Maximizing vehicle life is an important part of reducing the vehicle's overall environmental impact.

There's a great YouTube channel where the owner of a full-service used auto parts business takes apart modern engines and shows you what failed. No prior knowledge of engines is required to understand this. Some engines are spectacularly broken. And Eric talks about what will last, and what won't, with an entertaining sarcasm.

Recycling? The lead-acid primary battery gets removed, then the car gets crushed and shredded. Only the steel and the aluminum get recycled. Anyone who thinks that any other material in a car gets recycled in any quantity has never seen a car shredder in operation. ASR (Auto Shredder Residue) is a special waste stream now consisting mostly of mixed plastics, smashed safety glass, and the crap people leave in their cars when they junk them. All that plastic gets landfilled.

Comment Re:study confirms expectations (Score 1) 192

That's actually a good question. Inks have changed somewhat over the past 5,000 years, and there's no particular reason to think that tattoo inks have been equally mobile across this timeframe.

But now we come to a deeper point. Basically, tattoos (as I've always understand it) are surgically-engineered scars, with the scar tissue supposedly locking the ink in place. It's quite probable that my understanding is wrong - this isn't exactly an area I've really looked into in any depth, so the probability of me being right is rather slim. Nonetheless, if I had been correct, then you might well expect the stuff to stay there. Skin is highly permeable, but scar tissue less so. As long as the molecules exceed the size that can migrate, then you'd think it would be fine.

That it isn't fine shows that one or more of these ideas must be wrong.

Comment Re:Wrong question. (Score 1) 197

Investment is a tricky one.

I'd say that learning how to learn is probably the single-most valuable part of any degree, and anything that has any business calling itself a degree will make this a key aspect. And that, alone, makes a degree a good investment, as most people simply don't know how. They don't know where to look, how to look, how to tell what's useful, how to connect disparate research into something that could be used in a specific application, etc.

The actual specifics tend to be less important, as degree courses are well-behind the cutting edge and are necessarily grossly simplified because it's still really only crude foundational knowledge at this point. Students at undergraduate level simply don't know enough to know the truly interesting stuff.

And this is where it gets tricky. Because an undergraduate 4-year degree is aimed at producing thinkers. Those who want to do just the truly depressingly stupid stuff can get away with the 2 year courses. You do 4 years if you are actually serious about understanding. And, in all honesty, very few companies want entry-level who are competent at the craft, they want people who are fast and mindless. Nobody puts in four years of network theory or (Valhalla forbid) statistics for the purpose of being mindless. Not unless the stats destroyed their brain - which, to be honest, does happen.

Humanities does not make things easier. There would be a LOT of benefit in technical documentation to be written by folk who had some sort of command of the language they were using. Half the time, I'd accept stuff written by people who are merely passing acquaintances of the language. Vague awareness of there being a language would sometimes be an improvement. But that requires that people take a 2x4 to the usual cultural bias that you cannot be good at STEM and arts at the same time. (It's a particularly odd cultural bias, too, given how much Leonardo is held in high esteem and how neoclassical universities are either top or near-top in every country.)

So, yes, I'll agree a lot of degrees are useless for gaining employment and a lot of degrees for actually doing the work, but the overlap between these two is vague at times.

Comment Re:Directly monitored switches? (Score 1) 54

There is a possibility of a short-circuit causing an engine shutdown. Apparently, there is a known fault whereby a short can result in the FADEC "fail-safing" to engine shutdown, and this is one of the competing theories as the wiring apparently runs near a number of points in the aircraft with water (which is a really odd design choice).

Now, I'm not going to sit here and tell you that (a) the wiring actually runs there (the wiring block diagrams are easy to find, but block diagrams don't show actual wiring paths), (b) that there is anything to indicate that water could reach such wiring in a way that could cause a short, or (c) that it actually did so. I don't have that kind of information.

All I can tell you, at this point, is that aviation experts are saying that a short at such a location would cause an engine shutdown and that Boeing was aware of this risk.

I will leave it to the experts to debate why they're using electrical signalling (it's slower than fibre, heavier than fibre, can corrode, and can short) and whether the FADEC fail-safes are all that safe or just plain stupid. For a start, they get paid to shout at each other, and they actually know what specifics to shout at each other about.

But, if the claims are remotely accurate, then there were a number of well-known flaws in the design and I'm sure Boeing will just love to answer questions on why these weren't addressed. The problem being, of course, is that none of us know which of said claims are indeed remotely accurate, and that makes it easy for air crash investigators to go easy on manufacturers.

User Journal

Journal Journal: Audio processing and implications 1

Just as a thought experiment, I wondered just how sophisticated a sound engineering system someone like Delia Derbyshire could have had in 1964, and so set out to design one using nothing but the materials, components, and knowledge available at the time. In terms of sound quality, you could have matched anything produced in the early-to-mid 1980s. In terms of processing sophistication, you could have matched anything produced in the early 2000s. (What I came up with would take a large comple

Comment Re:Don't blame the pilot prematurely (Score 4, Insightful) 54

It's far from indisputable. Indeed, it's hotly disputed within the aviation industry. That does NOT mean that it was a short-circuit (although that is a theory that is under investigation), it merely means that "indisputable" is not the correct term to use here. You can argue probabilities or reasonableness, but you CANNOT argue "indisputable" when specialists in the field in question say that it is, in fact, disputed.

If you were to argue that the most probable cause was manual, then I think I could accept that. If you were to argue that Occam's Razor required that this be considered H0 and therefore a theory that must be falsified before others are considered, I'd not be quite so comfortable but would accept that you've got to have some sort of rigorous methodology and that's probably the sensible one.

But "indisputable"? No, we are not at that stage yet. We might reach that stage, but we're not there yet.

Comment Re:Not really new information... (Score 1) 79

I continue to use burned DVDs for backing up the critical stuff. Not perfect, of course, but not electromechanically-failure prone like a hard disk drive, not "terms of service" failure prone like cloud storage, and not "the charge magically held in the gate leaked away" failure prone. I have optical discs over 25 years old which are still perfectly readable.

Comment Read this (Score 1) 30

https://bigthink.com/starts-wi...

This describes the distortion that shows up in headlines like this one that seem to indicate that there is scientific evidence against the consensus, when really such evidence is very weak. Really, read that article.

Is Dark Energy real? Who knows; we don't really understand what's going on.

However, is the supernova evidence that the Universe is accelerating wrong? No. What's more, even if it were, you can come to the conclusion that the Universe is accelerating now without even using the supernova evidence, so if you want to show that that's wrong, you have a lot more to do than once again raise questions as to whether cosmic evolution of supernovae could explain Hubble Diagram.

Comment Analogy to BMW Subscription Heated Seats. (Score 1) 104

...re trying to make so forgive me if I am out to lunch, but this matters naught to the consumer. This is just back-office dealings that either adds $5 to the cost of a laptop or doesn't. It's there vendors choice what licenses they pay or don't pay. Then they get to set the price on their laptop after it all shapes out.

If the hardware is still present, but is disabled, you're still carrying around the hardware. Most importantly, you're probably still powering its logic even if it's inaccessible to you.

BMW, like most German cars, is overcomplicated and overpriced garbage sold only to self-proclaimed car enthusiasts who wouldn't know how to change a tire let alone a timing chain. BMW got themselves into a bit of controversy by including heated seats which only functioned by subscription.

Now, say I had bought a BMW but didn't want the heated seats. I don't pay for the subscription. There's no additional cost to me, the purchaser of the car, because the profit from the people who do opt for the subscription are the ones paying the cost of the extra hardware in my car, correct?

Wrong. I am now carrying around an extra-beefy alternator to power the heated seats. I am now carrying around all the extra wiring to power the heated seats. All of this impacts my performance and my fuel efficiency. And all of this extra complexity adds a failure liability when something damages part of the heated seat hardware. All for a feature I specifically did not ask for by refusing the subscription.

With a disabled chunk of logic embedded in a processor, is it a negligible cost and a negligible risk? Maybe, but as the purchaser, it's crap that I didn't ask for, and you are imposing on me. If I have to carry it around and power it up, I expect to be able to use it.

If the manufacturer doesn't want to supply a feature then they should not supply the hardware. Leave the spots on the circuit board unpopulated. In the case of a chip, leave it off the die.

Comment Re:Step 1: Don't own any BitCoin (Score 1) 85

"Your teeth will get through anything," Mr. Kayll advised. "But it will bloody well hurt."

Speak for yourself, my teeth will barely get through a cheese sandwich at my age.

There's nothing like a good smack to the beitzim to stop a would-be rapist. And there's nothing like biting someone if it's all the leverage you have.

Remember, this is not a video game or a sanctioned fight in a boxing ring. This is your life versus the life of a terrorist or other attacker. Kill or be killed. Learn to fight.

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