eSagan 🇮🇳 @crackurbones@qoto.org
Joined Nov 2019
So, I just discovered this website on #antennas: http://www.antenna-theory.com/
It not only has sections on different types of antennas but also introduces one to the preliminaries required to understand the subject (such as impedance matching on transmission lines with the help of Smith chart).
#electromagnetism #RFengineering #MicrowaveEngineering #TransmissionLines #SmithChart
Happy winter solstice, everyone from the northern hemisphere.
Timeline of the Universe
https://xkcd.com/2240/
eSagan 🇮🇳
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If you like pretty colors, lots of graphs, and astronomy, check this out: https://www.solarham.net/
#TIL Pluto was discovered using a machine called a blink comparator. This machine dates back to 1904 and — like many things — has been superseded by modern technology. In 1930, scientists knew there was something pulling the orbits of the planets but they didn’t know where it was.
The blink comparator helps you find something that moves by showing you two photographic plates in quick succession. Anything in the same spot on both plates appears stationary. Anything moving in the frame will stand out as it appears to jump from one spot to another.
eSagan 🇮🇳
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Graphene Is So Yesterday — Meet Borophene https://hackaday.com/2019/04/09/graphene-is-so-yesterday-meet-borophene/ #borophene #Chemistry #graphene #Science
Huawei P40 Pro may feature 5,500mAh, #graphene battery with 50W fast charging
We are finally in the graphene age!
Our universe is governed by four fundamental forces. At least that's what physicists have long thought.
Now, however, new research suggests that there's a fifth force, a discovery that could upend much of modern physics.
https://www.livescience.com/amp/fifth-force-could-exist.html
Listen To The Past: New Fossil Reveals How Hearing Skill Developed in Mammals
https://www.news18.com/amp/news/buzz/listen-to-the-past-new-fossil-reveals-how-hearing-skill-developed-in-mammals-2416279.html
eSagan 🇮🇳
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Free books, read online. Many authors and genres.
Don't know how they do it, get away with it, but...
Found a website listing many, many books, including the one with the cover below, by Charles Bukowski.
https://bookfrom.net/charles-bukowski/
You CAN read the whole book online it seems, and they have many other authors. From trashy breathless romance novels to works we can be grateful to get access to. Android app for mobile if needed.
Rather cool. Librarian in me wants to spread the word. Hush, hush. DMCA is a thing.
They do have many of Cory Doctorow's books too, excellent sci-fi writer. https://bookfrom.net/cory-doctorow/
eSagan 🇮🇳
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#Coffee Rat reminds us what rodents can teach science about #caffeine
https://www.inverse.com/amp/article/61532-coffee-rat-science-caffeine-studies
eSagan 🇮🇳
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WATER-FILLED BOTTLES + LIGHT
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SPOTLIGHT. In the 1700s, spherical glass bottles filled with water were used to focus candlelight for fine work such as lace making and surgery. -- see "Water sphere lens" https://www.exploratorium.edu/snacks/water-sphere-lens; and see Brian Lemin, "The Great Deception, Lace-makers lamps"
https://www2.cs.arizona.edu/patterns/weaving/webdocs/lb_lamps.pdf
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DIFFUSED LIGHT. In a modern-day emergency, a clear plastic bottle filled with water can be used to diffuse light -- converting a flash light into a lantern which illuminates an area instead of just one spot -- see "Plastic Bottle Lantern" https://www3.nhk.or.jp/nhkworld/en/radio/bosaiweb/craft/craft_20.html
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Sometimes I come across curious tidbits -- like this -- when I'm actively searching for something else. And I'm posting this just in case others might be interested, too.
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QUESTION? I wonder how the many uses of optics and lighting technology developed worldwide? My best guess is that the genesis of this story is probably in Europe.
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QOTO = Question Others to Teach Ourselves?
eSagan 🇮🇳
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WATER-FILLED BOTTLES + LIGHT
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In the images below, Japanese ukiyo-e woodblocks are being carved using traditional methods, including the lighting
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A glass flask full of water hangs between the woodblock and a light bulb. When the light from the bulb hits the flask it is refracted in all directions and eliminates shadows from the surface of the woodblock, enabling the artisan to see the finest of lines. -- see Brigitte Koyama-Richard, "Modern-day Artisans Carry On the “Ukiyo-e” Tradition." Nippon. March 6, 2014. https://www.nippon.com/en/views/b02306/modern-day-artisans-carry-on-the-ukiyo-e-tradition.html
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QUESTION? I wonder how the many uses of optics and lighting technology developed in Japan? My best guess is that the use of a water-filled glass globe to affect light was introduced to Japan by the Dutch.
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QOTO = Question Others to Teach Ourselves?
Why are moths attracted to light?
https://theconversation.com/why-are-moths-attracted-to-light-126545
eSagan 🇮🇳
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“Just as a mother would protect her only child with her life, even so let one cultivate a boundless love towards all beings.”
eSagan 🇮🇳
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Ocean waves have sounded exactly the same as long as anything.
Inside the Beach House Connecting the World’s Internet
https://www.youtube.com/watch?v=iMAThVcqzuk
In this interview with Robert Lawrence Kuhn for the PBS series Closer to Truth, the independent British physicist Julian Barbour endeavours to distinguish between our experience of time and its scientific underpinnings, including what has and hasn’t changed about our conception of time since we first looked to the skies to measure it.
https://aeon.co/videos/from-sky-charts-to-atomic-clocks-time-is-a-mysterious-story-that-humans-keep-inventing
Joined Nov 2019
