• 0 Posts
  • 18 Comments
Joined 1 year ago
cake
Cake day: June 16th, 2023

help-circle

  • With refresh rates like that, you must be talking about LED billboards.

    These are different from consumer monitors, which mostly use constant LED backlights and a liquid crystal layer to determine color.

    An LED bilboard is going to have a fuckton of singular LEDs - each of which can emit exactly one color - arranged in groups to form full pixels capable of displaying many colors. There is no extra LCD layer between your eyes and the billboard LEDs.

    The reason for the high refresh rates is because each led must be extinguished and and relit to redraw the image, and the eye is very good at picking up this strobe effect.

    The difference vs. a consumer display is that the backlight in a typical monitor is constant. Refreshes the screen involves sending updated instructions to the LCD layer, twisting the crystals and possibly changing the color they allow through.

    To make a crude concrete example:

    Imagine I am shining a white flashlight in your face. In front of the flashlight I put a colored piece of plastic so the light hitting you is colored. Then I change the plastic to one with a (slightly) different color. I do this 120 times per second. That is a typical consumer display.

    Now imagine I am shining a colored flashlight directly in your face. Then I turn it off and grab a flashlight of a different color and shine it in your face. Imagine I do that 120 times per second. That is an LED billboard.

    Which do you think is more likely to give you a headache?

    One final complication - the brightness of the LEDs is variable over time, they received a modulated signal rather than a steady voltage, so at lower refresh rates there will be a noticeable ripple across the image, similar to how early CRT screens could look.

    Increasing the refresh rate hides a lot of these problems.






  • Interesting how you ignore how the US did not recognize the goverment installed by the people of korea (PRK)

    The brief existence of the PRK has essentially no bearing on the civil war. It existed less than a year, and was dismantled in both the South and the North by the actions of the US and Soviet Union.

    Neither power cared to entertain what the people of Korea wanted in the Post-War period.

    I wonder what half-truth or outright lie y’all will respond with next to paint the US and SK as Satan next to the Angelic Soviet Union and DPRK.

    No power were the ‘good guys’. None had the moral high ground. All deserve blame for what happened. The history of the period is one of tragedy and ambition.

    None of that changes the fact that North Korea, backed by the Soviets and later China, started the shooting war by invading the South.









  • Fuel cells can be more efficient than combustion because of direct electrification. With combustion, there needs to be a boiler, turbine, etc and that adds to the losses through the system.

    At industrial scale, it is possible a turbine and boiler is probably the better bet, because the technology is very mature and large fuel cells may pose extra challenges with sourcing the membranes. It would need a more in-depth cost analysis.



  • Believe it or not, what you swallow has almost nothing to do with your weight. The only place the body absorbs energy from food is in the intestines, and the brain controls that process.

    The digestive tract is a tube, open at both ends, through which food passes. The process of extracting energy from that food is complex and highly tunable: the brain controls the production and secretion of hundreds of enzymes and other chemicals, as well as the physical action of the muscles lining the tube.

    The ‘basic physics’ here begins at the intestinal wall, not the mouth.


  • The fundamental issue with declining populations - fundamental as in regardless of the economic system of the country - is decreasing standard of living.

    The very simple metric is productivity-adjusted hours worked per person. This invariably falls in cases where overall population is declining, because populations age as they decline, and older people work less (retirement) than younger ones.

    As this metric falls, the country’s economy basically just produces less stuff per-person than it did in the past. This makes everyone effectively poorer.

    In extreme cases, there can also be issues with availability of services. E.g. healthcare: Each doctor/nurse/caregiver can only effectively attend to so many patients and this number is difficult to increase with technology.