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Joined 2 years ago
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Cake day: June 14th, 2023

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  • I mean, its trivial to prove something isn’t Bigfoot on the grounds that Bigfoot Isn’t Real. That’s just Hitchens’s Razor. The burden of proof is on the person presenting the claim, not the one refuting it.

    Shifting the burden of proof doesn’t disprove the claim. You can look at a picture and call someone an idiot for believing it’s bigfoot/a drone, but still not be able to swear that there is no way it could possibly be a drone.



  • It’s like trying to disprove Bigfoot. Someone comes to you with a shaky, out of focus video with no audio, time, date, or precise location.

    I can’t prove it’s not bigfoot. That doesn’t mean I think it is Bigfoot, or that you should think so.

    If you have good video and know where it was shot from and can cross-reference that with aircraft trackers? Then maybe they can do a good investigation. There’s been a few of those where it turns out to pretty obviously be a helicopter, a V-22, or just a 737.

    Especially since it’s rather hard to judge scale on airborne things some distance away.


  • Sorry, could have been clearer. I was talking about random dumb civilians.

    Quadcopters have been buzzing military bases for years, basically since they became available to the public.

    With all this PR about drones and people sometimes blaming the military, the number of dumb civilians thinking about ‘spying’ on military bases will be on the rise.


  • “We have had confirmed sightings at Picatinny Arsenal and Naval Weapons Station Earle,” the spokesperson said. “This is not a new issue for us. We’ve had to deal with drone incursions over our bases for quite a time now. It’s something that we routinely respond to in each and every case when reporting is cited.”

    It’s not explicitly stated, but my read is they get normal consumer-style quadcopters regularly, and this is simply a continuation of that. Perhaps an increase because people are now trying to explicitly spy on the military.

    The public drone sightings, on the other hand, definitely don’t seem to be consumer quadcopters. They mostly look suspiciously like 737s, V-22s, or out of focus stars.



  • It can vary depending on how the store sets the machines up. I’m on the wrong continent to use Walmart ones, but there’s definitely variation in how paranoid and slow they are set here.

    I feel it’s one of those cases where if you’re familiar with them and can think like the person who designed/programmed them, it can work pretty well. If you get confused by unfamiliar card terminals or a phone doing an update, you’re in trouble.

    E.g. it uses an expected weight and tolerance for products going into the scales. If this is produce you’ve just weighed, it’s going to be pretty precise. Same goes for something really light like a toothbrush; a 50% margin on tens of grams is still not much. If it’s a prepacked bag of oranges, then the weight could be way off (add a whole orange over the expected weight) so it won’t alarm on e.g. you putting a reusable shopping bag on the scale with the oranges. This lets you skip the annoying use-your-own-bag process.

    Knowing and remembering which is the next button to hit helps a lot.

    I find they’re fine for <5 items especially if the store is busy, but for a full trolley, you’re better off with a lane just for staging reasons.





  • Boring through rock is super slow and expensive, plus now your tunnel needs to be big enough to walk & run machines through, and needs aircon to keep it cool. It is done, but usually only in CBD areas where you need lots of cables and room for future expansion. Google ‘cable tunnel’ and you’ll find lots of examples. Trenching machines go through very expensive consumable digging teeth whereas bucket trucks are just a fancy forklift, burning fuel and needing hydraulic & engine maintenance.

    With high voltage cables, the (really thick) insulation gets really expensive, plus you need more conductor (copper/aluminium) because the insulation needs to stay cool. Aerial lines are directly air cooled (better cooling), and can run hotter, because the limit is the metal getting too hot and sagging, not the plastic degrading. Glass insulators are only needed at every tower and can be easily replaced.

    Because keeping the conductor small is important, you need to use expensive copper rather than cheap aluminium for cables.

    You also need regular joints which are very labour intensive, because they have to be perfect and you can’t make a cable the full length because you can’t ship a drum that big.

    If a cable fails, fixing it is much harder than fixing an aerial issue. There was a cable fault in LA in 1989 that took 8 months of round-the-clock work to fix. When a tower falls over (usually because of slope failure or undermining), temporary structures are usually up in a couple of days.

    Digging trenches under roads is much more invasive than pulling cables over roads, and rivers are even worse to deal with. It’s very common for underground cables to be converted to overhead when they cross a river before heading back underground.

    The Western HVDC Link between Scotland and England was built as an undersea cable because it’s so hard to get planning permission and land rights to do major projects in the UK, as High Speed 2 found out.



  • SomeoneSomewhere@lemmy.nztomemes@lemmy.worldSo beautiful
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    1 month ago

    Plenty of cities have ‘steam tunnels’ used for far more than just steam pipes, and sometimes no steam in there at all. It’s an awesome solution where you have reasonable density, and especially for within a facility/campus.

    I don’t think you’re going to see it happen in surburban streets. It’s the tyranny of the car.



  • SomeoneSomewhere@lemmy.nztomemes@lemmy.worldSo beautiful
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    1 month ago

    Underground works well for greenfields construction, where you can map everything out ahead of time and don’t have to deal with existing underground services.

    It’s manageable on low-density streets where its really only three waters and maybe some telephone lines.

    It’s a nightmare to underground existing infrastructure in dense environments. Underground is already full of three generations of critical comms, corroding gas, water, HV lines that will fail if you look at them wrong, and if you’re really unlucky, steam pipes too.