why

yt-dlp is a alternative for youtube-dl. Although mpv have a built-in youtube-dl, it is not competable with yt-dlp by default.

problem

Install mpv the way you prefer and install yt-dlp as well.
In my case I installed mpv and vapoursynth first and then I install yt-dlp. After installation first test both applications works as excepted.

At this point mpv http://xxxx.com works but built-in youtube-dl is used. In order to replace that, install yt-dlp-drop-in in AUR and for OS that don’t have such thing try ln -s ${which yt-dlp} /usr/bin/youtube-dl
And then

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#/mpv.conf

script-opts=ytdl_hook-ytdl_path=/usr/bin/yt-dlp

Now, yt-dlp is called successfully.

Call with arguments

only 480P videos played
So I tried add args behind /usr/bin/yt-dlp, is returns error
my solution is try add

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#~/.yt-dlp/config.txt

--cookies-from-browser firefox

In this way websides like bilibili works normally.

Measurement

Fog computing
using cloud computing for main computing workload, but put task that require more responsive calculation on the edge

• section

• package

• frame

• ACM Digital Library

• IEEE Xplore

• SpingerLink

• Science Direct(ELSEVIER)

• Wiley

• Taylor & Fracis

Decibels

Power ratios

10:1 = 10dB
1:1 = 0dB
100:1 = 20dB
1000:1 = 30dB
1:10 = -10dB

Approximately

1.25:1 = 1dB
2:1 = 3dB
4:1 = 6dB
8:1 = 9dB
1:4 = -6dB
32:1 = 15dB

Voltage ratios

10:1 = 20dB
1:1 = 0dB
100:1 = 40dB
1000:1 = 60dB
1:10 = -20dB

Approximately

2:1 = 6dB
4:1 = 12dB
8:1 = 18dB
1:4 = -12dB
32:1 = 30dB
1.4:1 = 1.5:1 = 3dB

example:
47527:1 this can be round up to 50000:1
which is $100,000\div 2 = 10^{5} * 2^{-2} = 50-3 dB = 47 dB$

• dBm, power compared to 1mW in dB

Feedline

• connect devices and their antenna

Antennas

• gain in dBi or dBd
• directionality
• polarization
• reciprocal
• Aperture

$path\ loss = \frac{(4\pi r)^{2}}{\lambda}$

$path\ loss(dB) = 10 \log_{10} \frac{(4\pi r)^{2}}{\lambda}$

$P_{RX} = \frac{P_{T}G_{T}G_{Rx}\lambda^{2}}{(4\pi r)^{2}}$