• 4 Posts
  • 393 Comments
Joined 10 months ago
cake
Cake day: August 16th, 2023

help-circle

  • I was just thinking about this. Love these videos. Cooling of a solar panel is a good application, as long as it gets cold enough for long enough to re-solidify at night.

    An alcohol/NaCl solution with a stabilizer can make an ice pack that freezes colder than water. That could be used to keep ice cream frozen in an ice chest.

    It would be cool to have recipes for a few different temperatures. There’s a German company Qool Products that sells PCM temperature elements (ice packs), at a variety of temperatures, to store ice cream up to red wine/cellar temp in their ice chest. With some trial and error I guess we could now make our own!






  • It seems it’s still an active debate and area of research, but the answer is more complex than wavelengths and emissivity. If you want to know whether black or white is cooler in the sun, it depends on: the breathability or knit, the amount of UV hitting the skin, the amount of skin contact with the fabric, wind speed, relative humidity, how the fabric wets and wicks moisture, and more. We could look at a black trash bag and say, well it’s transparent to IR, and it blocks the visible spectrum, therefore it’s a good shirt material to keep one cool. And obviously that would be wrong. In the same way it’s wrong to say: a white shirt feels less hot when you touch it, therefore it keeps the wearer cooler.





  • There are plenty of protected lanes in my city, but they just hide bicycles behind parked cars, making it less safe at every intersection.

    The only way I can think that might work better would be to convert a 3-lane road (with suicide/turn lane in center), into a 2-lane road. The center lane gets converted into a two-way bicycle road - raised up like a sidewalk with curved curb. No left turns allowed for cars, only right turns. This way bicycles are visible and protected.






  • Yeah it’s typically not used for dosages, rather it’s for concentrations in solution. However strictly speaking the grams cancel in the units of ng/kg and you are left with ppt. I think of ppm and ppt as very small percentages anyway. As per cent means part per one hundred. Can’t use “permille” because it means part per thousand but sounds like part per million.

    In the case of a lethal dose, I think it would be fine to say, “it’s lethal at a rate of 2 trillionths of body mass”.




  • Piwigo is more like a shared gallery. Users create album/folders and upload individual photos, which other users can access. Piwigo has poor support for videos and no support for Live Photos.

    Photoprism has only a single user for the free tier. It supports Live Photos and videos, and individual photo uploads. It does facial recognition tagging.

    Immich supports video/Live Photos, facial recognition, and has multiple users, but it expects a full backup/synchronization (not individual photos). Sharing between users is manual, not automatic or permissions-based like Piwigo. Each user has access only to their own backups or shared albums.

    In summary, I think Piwigo is the simplest to set up and use, but it doesn’t do much beyond photos - it’s a simple shared gallery. Photoprism is good and stable, but you have to pay a subscription for multiple user accounts. Immich is rapidly developing, which means things will break, but also it has the most features. My only issue with Immich is that I don’t want to use it as a backup - only as a “best of” shared gallery. While it’s possible with Immich, I would have to maintain an Immich album on my phone, and sync only that, and I would have to set up shares with other users manually.