Indeed. In that paper I linked to they specifically mention 60 GHz as a great re-use candidate exactly because the attenuation due to atmospheric gases/water is so horrendous.
I don't think your assertion that "2.4 GHz was opened up because of its high absorption by water molecules" is entirely true. It's a fact that water does absorb some power from 2.4GHz RF, but the reason microwave ovens are there is because it's dead center in an ISM band where things like that are allowed. There is no absorption peak for water at 2.45 GHz. The caption for figure 1 in the second link sums it up nicely: "The frequency for maximum dielectric loss lies higher than the 2.45 GHz (wavenumber 0.0817 cm-1, wavelength 12.24 cm) produced by most microwave ovens. This is so that the radiation is not totally adsorbed by the first layer of water it encounters and may penetrate further into the foodstuff, heating it more evenly; unabsorbed radiation passing through is mostly reflected back, due to the design of the microwave oven, and absorbed on later passes." If there were a peak at 2.45GHz, you'd boil the water off the first few mm of food and progressively leatherize the food all the way to the center.
Too cool! I visited the VLBA radio telescope on St. Croix when I was there and had a long, interesting chat with the tech on duty. I love how all the LNAs are liquid helium cooled in the broiling heat of the tropics. He did mention that they didn't bother with 96 GHz (I think it was) due to the extreme absorption there.
In the "Tracks in the Regolith" image, there are yellow streaks in the tire tracks that look like artifacts from color correction or brightness (over-) enhancement.
The FCC has a publication on the behavior of RF in the 30-300GHZ range, and the outlook is not rosy. Atmospheric gases, water vapor, rain drops, foliage, and other attenuation and noise sources make these frequencies problematic for medium- to long-range, high speed comms.
Using 60 GHz is interesting because it's attenuation is so high it can be reused every 4 km.
That ban needs repealing. Analog AMPS hasn't been used in forever, so that spectrum is no longer used for what they originally enacted the ban for. The digital replacement is/should be encrypted, so no ban is needed.
Also, be aware the gigabit ethernet does use all pairs. If you liven up the unused pins for your 10/100 (especially at higher voltages) dont accidentally plug it in to a gigabit port. Damage to the port will likely follow.
If you read the PoE spec, you'll see that the power is sent on both wires of at least two pair, and because the electrical spec calls for transformers on the receive end, the power will cause no issues. Since there's no voltage difference between the wires in the same pair, there's no problem with core saturation. For non-PoE devices, there's no difference. For PoE devices, the receive transformer has a center tap to access the power.
Let me ELY5: Teflon was invented and hailed as a wonder substance - inert, non-toxic, and slippery. Teflon was used in all manner of places, including cookware. Later it's found that using teflon-coated cookware _as intended*_ resulted in the deaths of birds and flu-like symptoms in humans.
No tinfoil hat here, I use teflon-coated pans regularly. You asked to see research re: problems with teflon used to coat pans, I provided them. Teflon is not the perfectly inert substance it was once touted to be - issues have come to light after years of use.
Look, all market-speak aside, here's what I'd expect from something called unlimited. I pay for 5 mbps download rate, let's say. I would expect 'unlimited' access to that to mean I could download at 5mbps 24x7x365. Anything else is not unlimited in my book. I was involved early on with Async Transfer Mode comms, where you'd get the agreed-upon data rate and QoS guarantees on your VC or nothing. That's what I'd like to see - guaranteed transfer rates that are actually usable 24x7.
If you want to sell me 'Up to 500 mbps as network congestion allows', by all means please do, but do NOT call it unlimited.
What you're calling 'network management' I call oversubscribing and under-engineering.
"Unlimited" means "WITHOUT LIMIT". They chose to use that word, not me. If they're going to say they offer unlimited, they darned well better, or get sued for fraud. Call it anything else you want - 'higher priority data rates", "premier service", etc but don't mangle definitions of words that are absolutes.
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I guess you don't have any incandescent light bulbs then?
So when will I be able to stream "My Word" and "My Music", auntie Beeb?
So Potassium is a great example of internal radiation, which is in biological equilibrium with your body almost always.
What really freaks laypeople out is when you tell them that radioactive potassium in their body gives off anti-matter. For the curious, K-40 sometimes decays to Ar-40 by emitting a positron and a neutrino.
So the next step is to replace those roads with cobblestones...
And after that, let's replace cars with horses!
I agree that crippling infrastructure in the name of safety is not the answer.
The RIAA/MPAA actually become a mafia entity with enforcers ...
Oh, so it's historical sci-fi then?
There's probably a clause in the agreement that allows them to use/sell your photos. If you're uploading data, they can't 'monetize' your data.
You give it to someone who might cause a lot of trouble to encourage them to take another path.
So what do you do when you give it to someone who wasn't supposed to cause a lot of trouble but did?
The odds of winning 6 coin tosses in a row is (IIRC) 0.5^6 which is a mere 1.56% chance. I'd like to know if Hillary provided the coins.
But the story is set in North Carolina.
Not to be a pedant, but the story is set in Charlottesville, Virginia. Home of UVA and a ton of snooty liberals.
According to Wallace and Gromit, the moon is made of Wensleydale.
Indeed. In that paper I linked to they specifically mention 60 GHz as a great re-use candidate exactly because the attenuation due to atmospheric gases/water is so horrendous.
I don't think your assertion that "2.4 GHz was opened up because of its high absorption by water molecules" is entirely true. It's a fact that water does absorb some power from 2.4GHz RF, but the reason microwave ovens are there is because it's dead center in an ISM band where things like that are allowed. There is no absorption peak for water at 2.45 GHz. The caption for figure 1 in the second link sums it up nicely: "The frequency for maximum dielectric loss lies higher than the 2.45 GHz (wavenumber 0.0817 cm-1, wavelength 12.24 cm) produced by most microwave ovens. This is so that the radiation is not totally adsorbed by the first layer of water it encounters and may penetrate further into the foodstuff, heating it more evenly; unabsorbed radiation passing through is mostly reflected back, due to the design of the microwave oven, and absorbed on later passes." If there were a peak at 2.45GHz, you'd boil the water off the first few mm of food and progressively leatherize the food all the way to the center.
Too cool! I visited the VLBA radio telescope on St. Croix when I was there and had a long, interesting chat with the tech on duty. I love how all the LNAs are liquid helium cooled in the broiling heat of the tropics. He did mention that they didn't bother with 96 GHz (I think it was) due to the extreme absorption there.
In the "Tracks in the Regolith" image, there are yellow streaks in the tire tracks that look like artifacts from color correction or brightness (over-) enhancement.
The FCC has a publication on the behavior of RF in the 30-300GHZ range, and the outlook is not rosy. Atmospheric gases, water vapor, rain drops, foliage, and other attenuation and noise sources make these frequencies problematic for medium- to long-range, high speed comms.
Using 60 GHz is interesting because it's attenuation is so high it can be reused every 4 km.
That would be the same pressure difference as a tank sealed at sea level being lowered into the ocean 34 feet. It's really not that much pressure.
That ban needs repealing. Analog AMPS hasn't been used in forever, so that spectrum is no longer used for what they originally enacted the ban for. The digital replacement is/should be encrypted, so no ban is needed.
Also, be aware the gigabit ethernet does use all pairs. If you liven up the unused pins for your 10/100 (especially at higher voltages) dont accidentally plug it in to a gigabit port. Damage to the port will likely follow.
If you read the PoE spec, you'll see that the power is sent on both wires of at least two pair, and because the electrical spec calls for transformers on the receive end, the power will cause no issues. Since there's no voltage difference between the wires in the same pair, there's no problem with core saturation. For non-PoE devices, there's no difference. For PoE devices, the receive transformer has a center tap to access the power.
Let me ELY5: Teflon was invented and hailed as a wonder substance - inert, non-toxic, and slippery. Teflon was used in all manner of places, including cookware. Later it's found that using teflon-coated cookware _as intended*_ resulted in the deaths of birds and flu-like symptoms in humans.
*Using a frying pan at temperatures between 300F and 450F is definitely normal use and can cause 'Teflon Flu'. So is 500F, if you're cooking bacon, which can cause acute lung injury.
Believe what you want, but the website of the company that the inventor worked for says "PTFE is inert to virtually all chemicals and is considered the most slippery material in existence.".
No tinfoil hat here, I use teflon-coated pans regularly. You asked to see research re: problems with teflon used to coat pans, I provided them. Teflon is not the perfectly inert substance it was once touted to be - issues have come to light after years of use.
Teflon fumes kill birds and can sicken humans. That's not pretty.
Already been done years ago, and by lots of others, too.
Look, all market-speak aside, here's what I'd expect from something called unlimited. I pay for 5 mbps download rate, let's say. I would expect 'unlimited' access to that to mean I could download at 5mbps 24x7x365. Anything else is not unlimited in my book. I was involved early on with Async Transfer Mode comms, where you'd get the agreed-upon data rate and QoS guarantees on your VC or nothing. That's what I'd like to see - guaranteed transfer rates that are actually usable 24x7.
If you want to sell me 'Up to 500 mbps as network congestion allows', by all means please do, but do NOT call it unlimited.
What you're calling 'network management' I call oversubscribing and under-engineering.
There goes Mr. Superior, spouting his rhetoric. Get over yourself, dude.
"Unlimited" means "WITHOUT LIMIT". They chose to use that word, not me. If they're going to say they offer unlimited, they darned well better, or get sued for fraud. Call it anything else you want - 'higher priority data rates", "premier service", etc but don't mangle definitions of words that are absolutes.