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InitialsDiceBearhttps://github.com/dicebear/dicebearhttps://creativecommons.org/publicdomain/zero/1.0/„Initials” (https://github.com/dicebear/dicebear) by „DiceBear”, licensed under „CC0 1.0” (https://creativecommons.org/publicdomain/zero/1.0/)JE
jeinzi @discuss.tchncs.de
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Comments 19
How much flow and volume from urination do you need to levitate your whole body for two seconds off the floor?
  • Aerospace engineer here. To levitate, the force of the exhausted mass flow (F=ṁ×v) has to equal the pull of gravity (F=m×g) on your body. The gravity of earth is g=9.81N/kg. Wikipedia says the average body mass is 62kg. It also says the bladder capacity of an adult is about 400ml, and I'll assume the density to be 1kg/l. You want to levitate for 2 seconds, so your mass flow needs to be ṁ=0.4kg/2s=0.2kg/s. If you rearrange the equation, you get v=m×g/ṁ=62kg×9.81N/kg/(0.2kg/s)=3041m/s.

    So if you manage to pee with a velocity of about 3km/s, you can levitate for 2 seconds with an average sized bladder.

    To achive that, your "exhaust" must be clenched to a diameter of about 0.29mm. This gives a cross-section of 0.066mm² or 6.6×10^-8m². Multiply that with the velocity of 3041m/s and you again get your flow of 0.2l/s.

    Of course, during those 2 seconds you loose mass and therefore, earth's pull on you gets less and you start to accelerate to about 0.23km/h, reaching a height of 4cm. If you took your special bladder to space, we can use the rocket equation to calculate that this stunt would accelerate you to 3041m/s×ln(62kg/61.6kg)=19.7m/s=71km/h

  • Any good games you can Reccomend?
  • The Long Dark? Offline single player survival in the postapocalyptic Canadian wildernis. There is a survival mode in which you can freely explore, but also a story mode and several challenges. In my opinion an extremely beautiful game and on the higher difficulties also extremly challenging.

  • *Permanently Deleted*
  • I can't say anything in regard to modern printers, but I don't trust any proprietary device connected to the internet. I have an old inkjet and an old laser printer, both without network functionality themselves - but I connected them via USB to a Raspberry Pi, which runs a printer server and makes them available on the local network. I can print and scan from my Linux laptop, and I also managed to print something from my Android phone. Haven't tried Windows yet. Configuration of the Raspberry Pi was easy, especially enabling scanning via the network.

  • SF ads call out tech firms for not paying for open source
  • Do you have an example? I am pretty sure that a FOSS license which requires companies to pay is impossible.

    Open Source guarantees that anyone can give the software to a company for free:

    "The license shall not restrict any party from selling or giving away the software as a component of an aggregate software distribution containing programs from several different sources. The license shall not require a royalty or other fee for such sale."

    And it guarantees that the company can then use it freely:

    "The license must not restrict anyone from making use of the program in a specific field of endeavor. For example, it may not restrict the program from being used in a business [...]"

    Quotes from the Open Source Definition.

  • Let’s make games open source, so future generations can enjoy them
  • Great idea, that's what I would probably do as well if I wanted to make a commercial game.

    Just remember, if you want something to be "Open Source" or "Free Software", the license can't prohibit commercial use [0][1]. If you really want others to be able to continue maintaining the project after you have stopped, they need to have permission to recoup their costs for servers, physical copies and to get paid for their development time. (Open Source) development needs to be financially sustainable; and if that is forbidden for future developers, it's not a community project anymore, i.e. not Open Source.

    Also, if by "attribution, no commercial use" you mean some Creative Commons license, they explicitly discourage use of their licenses for software [3].

    [0] https://opensource.org/osd

    [1] https://www.gnu.org/philosophy/free-sw.en.html#selling

    [3] https://creativecommons.org/faq/#can-i-apply-a-creative-commons-license-to-software

  • FUTO Keyboard app
  • It can't be included in the official F-Droid repos, as it is not Open Source.

    It's hardly better than any other proprietary software as the FUTO Temporary License does not allow users to make modifications and share them with non-programmers. They could include ads or spyware and no one would be allowed to strip that out and share the result with others.

    They also clearly forbid redistribution "directed towards [...] monetary compensation". But F-Droid has to be compensated for their server costs as well, and they ask for donations as they should be. That's why limiting commercial redistribution alone is a huge issue that would keep it from ever being called "Open Source" or "Free Software".

  • FUTO Keyboard app
  • It can't be included in the official F-Droid repos, as it is not Open Source.

    It's hardly better than any other proprietary software as the FUTO Temporary License does not allow users to make modifications and share them with non-programmers. They could include ads or spyware and no one would be allowed to strip that out and share the result with others.

    They also clearly forbid redistribution "directed towards [...] monetary compensation". But F-Droid has to be compensated for their server costs as well, and they ask for donations as they should be. That's why limiting commercial redistribution alone is a huge issue that would keep it from ever being called "Open Source" or "Free Software".

  • Help improve OpenStreetMap with StreetComplete
  • I've used it quite extensivly, big fan. It asks for further details on objects that have already been mapped, which also reveals things that don't exist anymore. It turns mapping into a really fun game with currently 163 different quests. The app also regularly asks you to verify opening hours or confirm the existence of certain objects. That being said, I almost always use it in conjunction with a real map editor, to add new stuff I find or to make more complex edits.

  • ich❓iel
  • Das stimmt auch, freie Weichware darf natürlich kommerziell vertrieben werden. Aber die nullte Freiheit ist, dass eine solche Anwendung zu jedem Zweck eingesetzt werden darf. Es darf also kein Unterschied gemacht werden zwischen privatem und kommerziellem Einsatz, letzterer darf also nicht ausgeschlossen werden, das meinte ich.

    Den Quellcode darf man übrigens genauso verkaufen wie die kompilierten Programme. Aber es gibt in der GPL ein paar Einschränkungen bezüglich des Preises den man verlangen darf, wenn man Kunden erst nur die Binärdatei ausgehändigt hat und die dann im Anschluss ihr Recht auf die Soße einfordern.