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Comment Re:Of course it could - but it won't (Score 1) 73

Sam D is very good, and I think his analysis is broadly correct, but I would be wary of treating him as apolitical. He's a leading thinker for the centre-right, along with Sam Bowman (Sam Freedman completes the clever-Sam-centrist trifecta, but is on the left rather than right).

Comment Re:It could (Score 1) 73

> Have grade-separated tracks that go above or below the roads.

Easier said than done.

Grade for typical trains is something like 2% or less, so raising a railway high enough to get over a roadway needs almost a quarter mile of track on either side minimum, so for a single rail bridge you just created at a half mile of impassible wall and cut a whole neighborhood in half. Automotive roads are better but still limited in a similar way. maybe triple the grade/a third the distance but you're still making a huge barrier.

So if you need to get through a town without having grade crossings you're basically stuck building the *entire* thing 14+ feet in the air, including the stations, which is outlandishly expensive both to build and to maintain.
=Smidge=

Comment Re:Could High-Speed Trains Shorten US Travel Times (Score 1) 73

One also needs to remember the US is a big country. The continental US is just a tiny bit smaller than the entire continent of Europe. The UK is only a few hundred miles tall - California is about 66% bigger. Travelling between the UK, France and Germany is only travelling between a few states.

A high speed train from New York to Chicago would be an undertaking of a huge scale it would put it in the top 10 total operational lengths of high speed rail. (That is, that one line would be longer than most countries total amount of operational high speed rail).

The US is huge. I think even California's attempt would rival many high speed rail lines in Europe.

The US is about the size of China, and China is leading the world (by a wide margin) on high speed rail, but they have several advantages in being able to bulldoze through a high speed rail line plus being able to do it with modern technology and very little existing infrastructure to get in the way. If you're laying down infrastructure, it's a lot easier to do it all at once than piecemeal over hundreds of years.

Comment Re: was that w,ritten by AI, or is it human gibber (Score 1) 53

Most jobs in a bureaucracy are useless and not productive

That's only true when jobs got replaced. The typing pool was an important part of business exchange because chickenscratch was hard to read. Schools had stopped teaching handwriting as a course - I said handwriting and nut cursive, because schools used to force you to be able to write legibly as a matter of course. If you had poor motor control you got stuck writing hours and hours of lines until it was pretty enough. Typewriters eliminated the need for people to be extremely neat and freed up education time from rote writing of letters to higher levels of instruction.

And it was the days where bad handwriting would get the back of your hand caned.

So the typing pool was necessary - you could get a letter drafted and typed out neatly and send it off to a client who would get this nice looking letter rather than a handwritten hard to decipher note. At the same time, the typing pool wrote up all the documentation for the project - you might share handwritten notes amongst the team, but you'd send your information out through the typing pool.

Once computers started becoming common, the need for the typing pool lessened and by the 90s was basically gone and everyone was expected to have basic skills.

Sure there are people doing useless jobs, but they're generally only one and two in oddball areas. There's no typing pool anymore because that was many people and as the need for them lessened, so did their numbers. Likewise, any engineering firm would have a calculator room where you'd send your calculations to be done by people with adding machines, and they almost went away with the advent of electronic calculators and computers. (NASA kept them around until the 1990s or so when Johnson retired because astronauts would ask her to confirm the computer's calculations).

The "useless" people you mention are generally the leftovers because someone somewhere still didn't want to do things themselves. They don't really accumulate.

What you are thinking of might be useless processes. You know, where you have to go through a whole requisitions process just to get a stapler where just getting the approvals often cost several times more than the item itself. That exists in a lot of places, and is what you are thinking of, because it's forcing people to be kept around who do nothing but manage the process.

But as DOGE showed, you can't just cut the people - because if the process needs to be done, you've just eliminated the people who are managing it and now the pipeline backs up. It only works if you cut the process first, then eliminate the people.

Alas, some process is necessary - often instituted as a CYA. Your boss asking you to do something illegal, and you asking them for it by email is a process so you have documentation. But it's a process, and that's how it all starts. Government is full of process because often it's to ensure fairness - you didn't exclude supplier X because you've have a beef with who runs the company - you excluded supplier X because product Y they offered didn't meet your specification Z. So when supplier X sues you (and they always do), you have a piece of paper that clearly shows that was the case. If they pursue the matter, you can ask them about why specification Z was not met by the product and why it's in the specification at all because the process is so well documented.

Think of when NASA awards SpaceX the next contract. ULA will likely tie up NASA and SpaceX in a lawsuit so convoluted because DOGE cut the people who would be able to demonstrate why SpaceX was the right choice and the documentation backing that up. And in the end, NASA, SpaceX and ULA would've spent billions on lawyers and dozens of years because DOGE saved $1M on personnel they thought was "unnecessary".

Comment Re: freight rail gets in the way in the usa! (Score 3, Interesting) 73

where would the land for that come from? Going around great lakes and through mountains are occupied routes. Are you going to push homes out of the way, bore through mountains? You can but it's expensive!

Generally a few things

1) eminent domain for countryside land
2) tunnels into cities.
3) once the network is in existence cities that don't have it lose out and will make a big effort to find land for

The distances in America are much bigger, so ideally you'd move to a faster rail standard, either simply double European width or maglev. Of Underground tunnels, though, are a really big thing because the main benefit of trains is that you can run them right to the center of the city so that people living there can leave their offices 20 minutes before the train, walk or take a taxi, get to the station 10 minutes before departure and still safely get their train.

At the other end it's even faster because you don't need the 10 minutes of leeway.

Comment Re: Stop now [and just give up] (Score 1) 91

We need people to stop worrying about their kids going to school in the dark. I walked through it throughout my schooling. Parents these days drop their kids off.

And get kids outside. "Freedom" as a kid was on a bike, and a pre-teen on a bike can easily cover several miles in a reasonable amount of time. Which in most places should be able to get you to a store and back.

The problem is generally infrastructure and poorly designed neighborhoods - ones where you can be 500 feet away as the crow flies, but take 5 miles to drive because the road system is absurdly designed. (Likewise fat chance at being able to walk there because no one thought people would want to walk - and 500 feet is likely quicker than driving 5 miles).

It's really the effect of a car-centric city design - using a bike to go to the store was a common thing - and cycling a few miles is trivial so a bike is real freedom to a kid able to ride to the store, or cycle to school. The problem is the roads are just not designed for anything but cars making them horrendously dangerous to walk the mile to school (a mile is around a 20 minute walk). Kids would file out the doors and walk in groups that separated as the streets branched out.

Now you have kids being dropped off at their friends place... 3 doors down. LItearlly - start the car, warm up the engine, drive the 100 feet to the friend's house, then drive back.

Walkable is not a bad word, and while hard to do in the suburbs because few of them have bodegas or convenience stores nearby enough, they're still compact that a bike ride can be possible. Many suburbs are often near enough to a big box store like a Walmart even as the crow flies, but the road design ensures you're driving 5 miles to get to the parking lot than if someone had the brilliant idea of making a cycle path so you could get there by cycling. Even the newest e-scooter trend makes this actually doable before one gets their driver's license.

Also cheaper than an Uber, and more exercise.

Comment Re:GLONASS showed Soviet weakness by the end (Score 1) 130

The main reason for pseudorandom codes was less about jamming and more about being able to grab a really weak signal buried in the noise. CDMA works by increasing the band's noise level but by running the noise through a correlator the signal.

CDMA is "magic" in that you can get at signals buried below the noise floor - that by running the received noise through a correlator, a desired signal could magically pop out of the noise. Well, it wasn't quite so - the real noise floor (caused by everything) is still an issue and buries all the signal, but the PRN transmissions added pseudo random noise so the apparent noise floor is higher, but that's still a usable signal.

The other way is the PRN spreads the signal out - current signals relied on narrowband transmissions contained in a very narrow part of the allocated spectrum. PRN modulation spread it out over many MHz (considered very advanced). Spread spectrum technology means narrowband interference is ignored (the correlation process takes the spread spectrum signal and makes it a narrowband signal which can be processed later, and vice-versa, so that interference appears as noise in the output)

As a result, the late 90s introduced 12 channel GPS receives - previous receivers could only lock onto one or a few satellites at a time to get the timing code, but the 12 channel receiver was made possible because of advances in digital signal processing technology. As the output was of a single RF input it could be digitally split internally and run through multiple correlator cores simultaneously trying to lock on to the PRN codes. This made for extremely fast initial fix times.

This is one reason why GPS startup times can vary - from over 25 minutes if the receiver has to manually try to acquire a signal in an unknown time and an unknown location - it's going to have to try all the PRN codes and slide them back and forth to see if they could decode a signal. Once it acquires a satellite lock, it then needs to download the almanac data which tells the receiver where the satellites are. It takes 12-15 minutes to download a complete copy of the almanac. Once the GPS receiver has an idea of satellite positions, knowing the ID of the current satellite it's acquired means it can narrow the search of satellites it should see to the ones that are in the same hemisphere as the satellite it can see. Since there can at most be 12 satellites in the hemisphere, the other 11 receives are programmed with the satellite PRN codes and they begin searching for that specific satellite.

Once you get 3 locked on then your position can be found. Now, most GPS receives aren't taken out of storage - they're used fairly often, which is why even a GPS receiver that's been sitting around, but not recently used can often initialize itself within 5 minutes - it assumes its location hasn't changed, and the almanac data it has is "good enough" so it can program the receivers with the PRN codes of the satellites it should be seeing at that point in time. It still needs to download the complete data, but a first lock is much quicker because the partial data it has is good enough to get first fix (which is why it's Time To First Fix - 25+ minutes from a complete initialization, 5 from a cold start - it still needs a complete copy of the almanac and that takes 12-15 minutes but it has existing data that is "good enough" for now).

The TOFF is down to 30 seconds if you've used the GPS recently and thus the almanac data is not only mostly up to date, but your position is likely the same and the PRN code search is a lot smaller since it's likely close but needs to account for drift. The search space is much smaller.

Your phone, though, has an advantage in that GPS almanac data is often available through side channels - it's part of the control plane. When your cellphone turns on, it locks onto a network (subscribed or not) and receives control plane data (tells it carrier and other things) which includes the current GPS almanac. This is transmitted very quickly (GPS datarate is around 160 bits/second, the control plane data rate is much faster so that took 12-15 minutes takes a few seconds or so). This happens anytime it has a signal - because even "No Service" still allows emergency calls and GPS data needs to be quickly available.

Note in North America, the E911 spec calls for GPS location to be sent via the control plane so your location is sent back while you're talking with the 911 operator. In Europe, less so and there are various specifications on sending emergency location data via the data plane, a slightly trickier prospect (what if the user has no data plan?).

Comment Re:Stop now [and just give up] (Score 1) 91

The problem with fusion is that until someone demonstrates a practical way to sustain it and produce energy, it's probably not going to get the kind of funding needed to demonstrate a practical way to sustain it and produce energy. At least not in less than several decades, and we don't have that long.

Like fossil fuels and nuclear, it is competing for funding with renewables. Renewables are mature, are cheap, and the market is growing. Because we are all capitalist societies, that's the only way we can address climate change.

I'd love to see fusion reactors in my lifetime, but nobody has a path to them that isn't full of huge challenges and unknowns.

Comment Re:Stop now (Score 1) 91

It's not necessarily dangerous. We can start small, and anything you put up to block the sun is going to be pushed away from it by the pressure of the photons, or you can stick it in a decaying orbit so it has a limited lifespan.

As long as it is designed to have a limited lifespan and clear itself out naturally, like the tens of thousands of LEO satellites we are throwing up now without much care, the damage that can be done is negligible. Once proven safe we can look at scaling it up, in a way that means if we stop replenishing it, it just goes away by itself after a while.

Comment Re:These articles are cool and all but (Score 1) 87

The cost of electricity in the UK is dictated by gas prices, and despite having our own North Sea gas we pay the international market rate. That went up when Putin started his war in Ukraine. The faster we get off gas, the sooner the bills can come down.

Before then we really need to break the link between gas prices and electricity prices. Currently the way the auction works, everyone gets paid the amount offered to gas generators (nuclear has a special deal that is insanely expensive but doesn't set a price floor).

Submission + - Company "Deep Fission" plans Underground SMRs (ieee.org)

jenningsthecat writes: IEEE Spectrum magazine reports that Deep Fission "hopes reactors in boreholes will be safer and cheaper":

By dropping a nuclear reactor 1.6 kilometers (1 mile) underground, Deep Fission aims to use the weight of a billion tons of rock and water as a natural containment system comparable to concrete domes and cooling towers. With the fission reaction occurring far below the surface, steam can safely circulate in a closed loop to generate power.

In October the startup announced that prospective customers had "signed non-binding letters of intent for 12.5 gigawatts of power involving data center developers, industrial parks, and other (mostly undisclosed) strategic partners, with initial sites under consideration in Kansas, Texas, and Utah". The article continues:

Deep Fission’s small modular reactor (SMR), called Gravity, is designed to stand 9 meters tall while remaining slim enough to fit inside a borehole roughly three-quarters of a meter wide. The company says its modular approach allows multiple 15-megawatt reactors to be clustered on a single site: A block of 10 would total 150 MW, and Deep Fission claims that larger groupings could scale to 1.5 GW.

"We are unique in that we’ve combined three existing mature technologies in a way that nobody had ever thought of before". The company claims that "using geological depth as containment could make nuclear energy cheaper, safer, and deployable in months at a fraction of a conventional plant’s footprint. Still, independent experts say the underground design introduces its own uncertainties, both regulatory and practical."

Shoutout to Hackaday.com for alerting me to this story.

Comment Re:This is not a job for a corporation to do (Score 1) 91

"why did we continue to feed them?" Did you forget about how the whole industrial Western world runs on oil and that alternatives didn't meaningfully exist until the last decade (and even now they're basically edge cases)?

It would that spoil your little "durr it's all them corporations fault!" oversimplification?

Fair point, so I'll re-phrase my question: "why did we bury our heads in the sand and refuse to hold both corporations and ourselves accountable".

We were still always going to end up with AGW - but we could have been working on mitigation and reduction strategies for at least five decades which we mostly lost, partly to our own heads-in-the-sand behaviour and largely to corporate sand-bagging.

BTW, I still think "durr it's mostly them corporations fault!" We could have had comfortable, happy, modern existences without a lot of the environmentally costly - and unhealthy - excesses which we were seduced and coerced into in the name of obscene profit and corporate hegemony.

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