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Cake day: June 14th, 2023

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  • Bernoulli’s explanation and Newton’s explanation are the same explanation made from different frames of reference. They’re equal, I don’t understand why people insist that one or the other is incomplete or that they somehow both have different contributions to an airplane’s flight. They’re the same. The airplane flies because the air pushes it up turning some of the energy from its substantial forward movement through said air into enough upward acceleration to counteract gravity. That happens both due to pressure differential AND the sum of the deflection of air in exactly the same measure, they are directly linked and have to be equal. Bernoulli’s explanation is one particularly nuanced and clever way of looking at and understanding the exact mechanics of how that happens and if you plug the resulting values into Newton’s math it matches perfectly. The zero “angle of attack” for a cambered airfoil shape is actually measured this way not by measuring the angles of the physical surfaces or anything like that. The Newtonian explanation is just another way of looking at it. Either way it requires intense computations to come to exact numbers, but the numbers are the same either way. The pressure differential of the air IS the mechanical force of the air, happening as an equal and opposite direction to the deflection of the volume of air the plane is flying through, either of which is what we call lift. They’re all the same thing, happening at the same time and yes you can look at them from different perspectives but that doesn’t mean one perspective is wrong and the other is right. They’re all accurately describing the same thing. It is useful to know both, but not necessary and it does not make either of them incorrect.

    This discussion always reminds me of the “airplane on a treadmill” argument where both sides read the premise differently and scream at each other that only their way of interpreting the question is right.




  • Matrix and its implementations like Synapse have a very intimidating architecture (I’d go as far as to call most of the implementations somewhat overengineered) and the documentation ranges from inconsistent to horrific. I ran into this particular situation myself, Fortunately this particular step you’re overthinking it. You can use any random string you want. It doesn’t even have to be random, just as long as what you put in the config file matches. It’s basically just a temporary admin password.

    Matrix was by far the worst thing I’ve ever tried to self-host. It’s a hot mess. Good luck, I think you’re close to the finish line.


  • Most cheap non-dimmable LEDs have drivers that use resistors to determine the current to drive through the LEDs. As a rule, these are always set too high to overdrive the LEDs (sometimes as much as twice their rated current) for marginal brightness gains and to burn out the bulb prematurely. I’m obviously unable to actually see directly into the operation of the great minds that design LED lightbulbs but logic leaves me with only those two plausible conclusions, I’ll let you decide which motivation you think is a bigger factor for most manufacturers.

    Conveniently, most manufacturers carefully fine-tune this value to prematurely destroy the LEDs at just the right time, which requires careful balancing of resistors, and even MORE conveniently (for us) the cheapest way for them to do this is typically to use two resistors. And MOST conveniently (for us), if you were to carelessly break one of the pair of resistors they use, and leave the other one intact, the current would immediately drop to a very reasonable and appropriate level, generating much less heat, drawing much less power, making LED death extremely unlikely, and only modestly reducing brightness in many cases, because LEDs have non-linear brightness and the heavily overdriven ones are typically FAR beyond the point of diminishing returns. In some cases the reduction in power results in basically no visible difference in light output. In some cases it can be argued they’re literally stealing extra power from your electricity bill and using it as an electric heater for no purpose other than to burn out your own light bulbs prematurely so you have to replace them.

    The good news is, like I said, removing one of the responsible resistors instantly solves the design flaw and is usually quite easy even without any special tools or electronics knowledge. BigCliveDotCom calls this “Doobying” the bulbs after the Dubai bulbs that were mentioned in other comments. If you watch some of his videos about LED bulbs you should be able to see the pattern of which resistors to remove, if they are on the board they will basically always be right next to each other and relatively small values (typically in the 20 ohms to 200 ohms range). The only modification I make to his procedure is that I prefer to remove the HIGHER value of the two resistors instead of the lower one, which results in perhaps somewhat less lifetime preservation (still much more than the original setting) and less power savings, but more brightness, and is usually adequately good for my purposes. I also use sturdy tweezers to remove the resistor instead of a screwdriver which seems to me that it would have a higher risk of collateral damage.

    Is it a lot of work for a single light bulb? Kind of, yes. But once you get it done a bunch of times, you’ll probably rarely have to do it again, as these bulbs last almost forever. In fact, I have yet to have one actually fail, I am mostly just replacing the occasional old unmodified LED bulb from time to time.

    This will not work with dimmable bulbs or certain fancy high end bulbs. Also some are much, much easier to modify than others. Clive calls the ones that are relatively easy “hackable” and it’s really a crapshoot to find them. Some have covers/bulbs/diffusers that are nearly impossible to remove without catastrophic damage to the bulb and/or your hands. Others simply use a different circuit design that doesn’t have resistors. Some only have a single resistor, meaning to change the value you need to solder a new one in its place. In my experience, the bargain-basement, junkiest, least reliable bulbs tend to be the easiest to hack this way and often skimp on things like “gluing the lens on” so it’s easy to get off. But you’ll have to experiment to find a brand and style that works well for this.



  • While it sounds a bit hacky, I think this is an underrated solution. It’s actually quite a clever way to bypass the whole problem. Physics is your enemy here, not economics.

    This is kind of like trying to find an electric motor with the highest efficiency and torque at 1 RPM. While it’s not theoretically impossible, it’s not just a matter of price or design, it’s a matter of asking the equipment to do something it’s simply not good at, while you want to do it really well. It can’t, certainly not affordably or without significant compromises in other areas. In the case of a motor, you’d be better off letting the motor spin at its much higher optimal RPM and gear it down, even though there will be a little loss in the geartrain it’s still a much better solution overall and that’s why essentially every low speed motor is designed this way.

    In the case of an ammeter, it seems totally reasonable to bring it up to a more ideal operating range by adding a constant artificial load. In fact the high precision/low range multimeters and oscilloscopes are usually internally doing almost exactly the same thing with their probes, just in a somewhat more complex way behind the scenes.


  • The end result is exactly the same.

    The difference is that you can install an iso on a computer without an internet connection. The normal iso contains copies of most or all relevant packages. Although maybe not all of the latest and most up to date ones, the bulk are enough to get you started. The net install, like the name suggests, requires an internet connection to download packages for anything except the most minimal, bare-bones configuration. The connection would hopefully be nearly as fast if not faster than the iso and be guaranteed to have the latest updates available which the iso may not. While such a fast connection is usually taken for granted nowadays, it is not always available in some situations and locations, it is not always convenient, and some hardware may have difficulty with the network stack that may be difficult to resolve before a full system is installed or may require specialized tools to configure or diagnose that are only available as packages.

    In almost all cases, the netinst works great and is a more efficient and sensible way to install. However, if it doesn’t work well in your particular situation, the iso will be more reliable, with some downsides and redundancy that wastes disk space and time.

    Things like windows updates and some large and complex software programs and systems often come with similar “web” and “offline” installers that make the same distinctions for the same reasons. The tradeoff is the same, as both options have valid use cases.


  • To be fair, in the case of something like a Linux ISO, you are only a tiny fraction of the target or you may not even need to be the target at all to become collateral damage. You only need to be worth $1 to the attacker if there’s 99,999 other people downloading it too, or if there’s one other guy who is worth $99,999 and you don’t need to be worth anything if the guy/organization they’re targeting is worth $10 million. Obviously there are other challenges that would be involved in attacking the torrent swarm like the fact that you’re not likely to have a sole seeder with corrupted checksums, and a naive implementation will almost certainly end up with a corrupted file instead of a working attack, but to someone with the resources and motivation to plan something like this it could get dangerous pretty quickly.

    Supply chain attacks are increasingly becoming a serious risk, and we do need to start looking at upgrading security on things like the checksums we’re using to harden them against attackers, who are realizing that this can be a very effective and relatively cheap way to widely distribute malware.


  • I still use Nextcloud for syncing documents and other basic stuff that is relatively simple. But I started getting glacial sync times consuming large amounts of CPU and running into lots of conflicts as more and more got added. For higher performance, more demanding sync tasks involving huge numbers of files, large file sizes, and rapid changes, I’ve started using Syncthing and am much, much happier with it. Nextcloud sync seems to be sort of a jack of all trades, master of none, kind of thing. Whereas Syncthing is a one trick pony that does that trick very, very well.


  • The setting you described sounds like a motherboard manufacturer issue. There’s no reason for it not to default to “auto” unless that somehow limits something else they wanted to have on by default. They choose the defaults, and they chose that one, even if it’s stupid. Either that, or you set it somehow previously and didn’t realize or forgot you did.


  • I feel like you are the one who is confusing a “NAS device” or “NAS appliance” as in a device that is specifically designed and primarily intended to provide NAS services (ie, its main attribute is large disks, with little design weight given to processing, RAM or other components except to the extent needed to provide NAS service), and a NAS service itself, which can be provided by any generic device simultaneously capable of both storage and networking, although often quite poorly.

    You are asserting the term “NAS” in this thread refers exclusively to the former device/appliance, everyone else is assuming the latter. In fact, both are correct and context suggests the latter, although I’m sure given your behavior in this thread you will promptly reply that only your interpretation is correct and everyone else is wrong. If you want to assert that, go right ahead and make yourself look foolish.





  • It is mostly a myth (and scare tactic invented by copyright trolls and encouraged by overzealous virus scanners) that pirated games are always riddled with viruses. They certainly can be, if you download them from untrustworthy sources, but if you’re familiar with the actual piracy scene, you have to understand that trust is and always will be a huge part of it, ways to build trust are built into the community, that’s why trust and reputation are valued higher than even the software itself. Those names embedded into the torrent names, the people and the release groups they come from, the sources where they’re distributed, have meaning to the community, and this is why. Nobody’s going to blow 20 years of reputation to try to sneak a virus into their keygen. All the virus scans that say “Virus detected! ALARM! ALARM!” on every keygen you download? If you look at the actual detection information about what it actually detected, and you dig deep enough through their obfuscated scary-severity-risks-wall-of-text, you’ll find that in almost all cases, it’s actually just a generic, non-specific detection of “tools associated with piracy or hacking” or something along those lines. They all have their own ways of spinning it, but in every case it’s literally detecting the fact that it’s a keygen, and saying “that’s scary! you won’t want pirated illegal software on your computer right?! Don’t worry, I, your noble antivirus program will helpfully delete it for you!”

    It’s not as scary as you think, they just want you to think it is, because it helps drive people back to paying for their software. It’s classic FUD tactics and they’re all part of it. Antivirus companies are part of the same racket, they want you paying for their software too.


  • Keep the gray plastic. Remove black clip around the vertical wheel post in the gray plastic. Remove wheel and wheel post. Buy new wheel. Installl new wheel. It will be easier to find a new wheel once you have the old wheel out so you can take measurements. but it’s likely something pretty standard, off-the-shelf. Wheels are something that companies buy, they rarely build them themselves. They typically come as a castoring assembly with wheel, axle, spindle, and attachment post in a variety of common sizes and with a dizzying variety of actual wheels.



  • a) Forecasts are very resource-intensive, they are performed on a specific schedule using a computational forecast model. Updating the predictions would require inputting new data and running the model again, and by the time they do that, the next forecast will already be out.

    b) Do they know it’s wrong? Where did you get the temperature? From an official weather station? If not, there is no reason to imagine that someone is noticing that this one particular model run was wrong in one particular spot across the whole country and trying to fix it in real time.

    c) If you did get the current temperature from an official weather station, that IS your update for it. Real time data from official weather stations is always going to trump the forecast model. What would be the point of updating the forecast when the current measured data from the weather station is now available? That’s like driving down the highway and saying “I was predicting my speed would be close to 65mph, but due to the heavy traffic I’m seeing today, I’m going to re-estimate my speed to be 45mph” when you have a perfectly accurate speedometer right in front of you telling you exactly what speed you are going at all times. Forecasts are only useful for the future, and they can be wrong.