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Cake day: June 14th, 2023

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  • I love this. I have a box I’ve been wanting to move to a family members place because they have fiber and I don’t. They’re heavy users of the plex server I have on there, so they’re happy to host it, but if I ever had issues around anything boot related I’d be down until I could physically get there.

    This would also be awesome for troubleshooting some RasPi stuff where I kind of want the DE every now and then but mostly let it run headless.



  • I think it’s because ones a drug prescribed for a medical condition. So you may have a condition where your doctor says “stay away from cured meats” but might prescribe you a drug that unwittingly has what they’re looking to avoid. And just in general drugs give you a lot of control: there should only be what you know and want in there. Foods a big ol mess of compounds. My heart meds get recalled all the time for less acrylamide than I’d get in a flame grilled burger.



  • Thank you for the tips! It turns out the files weren’t corrupted at all, it was a transcoding issue somewhere in the hardware acceleration stack. I’ve disabled it which will cause some bottlenecks, but there’s more than enough processing power in the rig for the limited amount of people that use it simultaneously.

    Thank you for the reply and the links though! My original plan was NOT to fix the files, just to figure out which had an issue and re-download them. Like I said it turns out that was unnecessary.

    Thanks all the same for pointing me to that thread. I do want to start screwing around with some imagine manipulation at some point, and this has already been really educational in learning the top level flow of this kind of thing. Again, I’m more used to passing data for sensors and motors.



  • I’m just going to give a quick overview of what wastewater treatment is and does.

    The basic idea is that you can have something like a can of 7-up, it looks clean, but would kill a fish dead. It’s got loads of dissolved sugar, and if you dumped it into a river, microbes would go nots on the sugar, sucking out all the oxygen as they grew, and causing a boatload of other problems.

    But you can’t filter dissolved sugar. I mean you can but it requires a highly specialized filter that would imeaditley foul is wastewater. And we’re not just talking dissolved sugar, there’s a whole range of everything in there.

    So we do something very simple: we let the 7up grow moldy. 7 up would go through a coffee filter, but mold wouldnt. We let the mold suck up the sugar, then seperate that.

    In reality it’s a bit different but that’s the idea. We grow a ton of microbes, let them suck everything out, then move them to another tank where they all stick together and settle to the bottom. The result is that the liquid at the top of the tank is clear, and free of anything dissolved as the bugs ate it all. (how we then get rid of all of that bug mass is whole other thing but basically we squeeze all the water out we can and it becomes dirt).

    The problem with stuff like pfoas or any other micropollutant is that the bugs aren’t that interested. And they’re at such a low concentration it’s incredibly hard to get such a small amount out of millions of gallons every day.

    Wastewater treatment was meant to mimic natural ecology so that when it was discharged we didn’t overwhelm the environment. If you poop in the woods, it’s probably not a problem. If everyone poops in the same area of the woods… The woods are going to look different and not in a good way. We solved that problem, but not the one of what to do when the poop is “radioactive”.

    One last note: what I described above is secondary settling (letting the bugs settle and taking the liquid off the top). There ARE filters to seperate the bugs from the liquid, but they are no where near selective enough for specific compounds. Again, think coffee strainer.


  • Bare with me here because I am not an expert. I think what they’re getting is the same as how gravity doesn’t exist. Vsauce did a great video on that, but the general notion is that because space time is curved, objects traveling in streight lines will appear to be drawn closer to one another. “Gravity” isn’t fundamental, warping spacetime is. Nothing changed but our understanding of it, which does matter for some more complicated areas.

    I think this is similar. Just like gravity “doesn’t exisit”, it’s just an emergent phenomenon: they’re saying so is time. They’re saying time isn’t fundemental, except that it’s an expected phenomenon that would arise from other factors, those factors being proposed to be some entanglement crap I have zero ability to talk about.

    And I’m putting some words in their mouth with “time isn’t fundemental”. What they’re really doing is proposing a new definition that better fits observed phenomenon/models.

    And still, none of this explains why we still have daylights savings time.








  • Yes, sorry, I did oversimplify to the local network. On your local network everything is always listening, but absolutely your home router/modem in Kansas does NOT excite some wires in Tokyo unless you tell it to lol.

    And it sounds like you know way more about the software than I do, but I can say with confidence that when a router starts putting ossilating high/low on a cable, everything on that cable “sees” it. I’m fairly sure that’s why different address blocks have the limits they do; there’s only so many addresses you can have without needing to ossiclate that voltage stupid fast.

    You should look into some of the serial examples for raspberry pis/ arduinos, with your software background you’d probably really enjoy it! It’s funny to run into things like the fact that you can have issues like the wire not going back to low sometimes, and the myriad physical issues.

    And seriously check out MODBUS. It’s crazy how “simple” it is. With no handshake and a standardized data format, you can trigger all sorts of stuff. That’s the protocol that controls most people industrial things, including GIANT pumps and valves.


  • I wrote up a whole thing that didn’t post. There’s good answers here but I think that, like me, you wanted a more “voltage based” one.

    Short answer is they don’t. Everything on the network is always listening, and security is based solely off of a handshake. Everything is always employing a fancy multimeter that measures voltage high/low as a 1/0 turning it from bits to bytes etc. The router listens to that and decides where to send it upstream, which it isolates from downstream.

    For a realllllly basic example look at the modbus protocol. That’s also why industrial equipment folks get real touchy about network access. For things like computers, theres talk back and forth to verify. Modbus is just “if the byte is the thing I do the thing”. But fundamentally, that’s the physical basis: all devices are always listening, the TCP/IP stack is what tells them what to disregard.




  • Well right, which is why they’re separate things entirely. And I am definitely taking some poetic license, but I outlined a pretty concrete example of how the way the scientific process is structured it’s a tool for what’s demonstrable, not inherently what’s correct. In what I outlined, it’s possible you could never gather that data. In every sense that matters most of the universe would no longer exist.

    You can do the same thing in reverse (we’ll never actually know what happened at the big bang, we weren’t there, still we can figure out a lot). It just drives the point home more when you realize there are things you can look at, observe, make hypothesis and test against here today, that will essentially leave the realm of science in the future.

    So again, this is definitely some navel gazing, and I’m just about as atheistic as they come, but the original spawn of this part of the thread was “how can any scientist be religious”. It’s because the scientific process isn’t actually concerned with being “correct”, now or in the future, just plausible and useful. I’ve worked in the lab with folks who viewed their work as understanding the universe someone created for them. That’s entirely compatible with the scientific method. You can take a minute to appreciate the insanity and beauty of everything we know about this universe and the fact that were even capable of comprehending some of it without it corrupting your scientific method. Some people choose to appreciate that insanity and beauty and assign divine intent. So long as the graph has a decent R^2, that’s just fine.


  • Science and religion (in the broad sense, not specific statements of a religion) are just two entirely separate things. Faith by it’s definition exists outside anything testable, so it’s just not part of science. Here’s the one hitch: science does in-fact point to faith. Bare with me here.

    We know with whatever certainty anyone would require that the universe is expanding, and that the rate of that expansion is accelerating. We know with certainty that >90% of all that we know is there, just by looking up, is already permanently and irrevocably beyond our grasp. It will all blink out of the night sky, and no interaction will ever be possible.

    Future scientists (human, alien, whatever) will look at certain phenomena, the cause of which we today would know to be a specific galaxy, etc, but we would have no way to gather a single shred of evidence. There would be no way, literally none, to ever interreact with those stellar structures.

    To these future scientists you would be citing ancient texts and proposing a 100% untestable hypothesis. You would be proposing literal gods outside of the machine. And you’d be right. But it would all have to be taken on faith.


  • ABS/pumping the brakes is implemented because sliding friction is less that static friction. It’s why you can nudge something on a slope to start sliding and it doesn’t stop but would have happily sat there before hand.

    Your car wheels experience static friction because while in motion the patch in contact with the road isn’t moving. Or at least they do until you skid.

    So ABS brakes/releases to get a new round of static friction.

    Pumping the brakes is probably a phrase that came from before power assisted brakes (when you were manually pressurizing the hydraulics) but still had relevance because it was also ABS.