No, they'll float. It's all they need to do.
on
Wi-Fi From The Sky
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· Score: 4, Informative
You can't make them stationary....
Let them float, they get blown around (world) by the jet streams. (Lots of surface area * 100 m/s winds).
Yes you can. The jet streams are phenomena of the troposphere. The stratosphere, where these things would float, is stratified (thus the name) and has little wind.
There was another company looking to piggy-back on the National Weather Service's twice-daily balloon sounding probes to provide cellular service in unserved areas. The latex balloons climb to extreme altitudes, and then often hang for 24 hours or more without moving much (according to the article) before bursting. If the relay balloons float at similar altitudes, they would require little power for stationkeeping.
Tie them to ground.. The tie down cable becomes an aviation hazard.
Big deal, you bar air traffic from the area. We may soon be doing the same to generate electricity, with tethers perhaps 3 miles long; check out gyromills for a jolt to your weltanschauüng.
Volume needed to lift ~10 pounds to 75,000 ft requires a balloon 30 to 40feet in diameter.
Have you looked at the balloons used to loft cosmic-ray, infrared and the cosmic-background radiation experiments lately? Boomerang flew at 120,000 feet, thus requiring a balloon several times the volume required to loft a payload to a mere 65,000 feet. There is a lot of established expertise, and while this can't be considered a trivial exercise it isn't going to require much new work.
That should read "why do [scientists sometimes] do this?"
I think you mean "Why do (so-called science) journalists so often do this?"
My speculation:
An education system which doesn't teach science worth a damn.
Journalism schools and editors who don't care about accuracy in science reporting, in no small part because they are writing for a public which failed to learn science in the education system and wouldn't know the difference.
An intelligentsia which doesn't hold either of the previous two to account.
Now things are swinging back in that direction again. That kind of personal knowledge, since lost in the underflow of automation, is being extracted again by the current providers of those services.
Except that the knowledge is no longer personal, it is impersonal and global. That's the difference. In the past, when you saw the clerk, the clerk saw you. Today, when you see the card-swipe at the U-scan, you see nobody, and anyone who cares to buy, legislate or hack access to the database sees you. And the memory of the system is absolutely perfect, a trait never possessed by humans absent a whole lot of chicken-scratches on paper (or twists in knitting...)
What chance does an unaugmented human have against such an apparatus?
I'm amazed that this has happened. I too had written off Blacklight years ago as being just another joke. We'll see.
I still do. It usually takes about 20 years for something to progress from proven scientific discovery to engineered product, and this discovery is at least worth a Nobel prize. In other words, if these people had a real discovery they would have a million bucks as seed capital for their business. I don't recall seeing "Nobel Laureate" after any of their names, do you?
I doubt that the police agencies will find this outfit to be a joke; I think they'll call it criminal fraud.
Dude, escape velocity is only twice the energy of orbital velocity. Orbit doesn't impress me; I know too many real rocket scientists.
I was also very pessimistic. At 50,000 megawatt-days per ton over 730 days burn time (roughly 68 megawatts average) and 4 megawatt-days to achieve orbit, the fuel would produce the energy to loft itself in about an hour and a half. It would produce the energy to put itself onto an escape trajectory in about three hours.
The energy required to put a ton of mass into orbit is roughly what it takes to accelerate it to 8000 meters per second. Call it 32 megajoules per kilogram, or 32 gigajoules per metric ton. Multiply by ten for inefficiencies if you like: 320 gigajoules per ton.
Typical "burnup" for nuclear fuel in commercial pressurized-water reactors (PWRs) is something on the order of 50,000 megawatt-DAYS per ton. A megawatt-day is 86.4 gigajoules. You could produce the energy to throw the fuel into orbit in 4 days; escape velocity would take 8 days. And that's assuming you don't do anything intelligent like reprocessing the fuel so you only have to dispose of the actual fission products (you can keep the leftover uranium and plutonium and throw them right back into the reactor); if you reprocessed, you would only need to get rid of 10% or less of the total fuel mass per cycle. A load of fuel lasts a couple of years. All in all, you are talking about 1% of the energy output of the fuel to send it all away from Earth after you're done.
This is not to say that it would be smart to do that if you could, or that the engineering required would be feasible even if it was smart. But nothing in the energetics prevents you from doing so.
... the influence of synthetic hormones on wildlife is threatening aquatic species by feminizing males. (No, those hormones are not rendered inactive either by the body or by sewage-treatment plants.) Latex, so long as you aren't allergic to it, at least has the benefit that it's biodegradable.
You missed a quip there
on
Green Geeks?
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· Score: 1
I was giving an economist friend a hard time; someone commented how he'd been in a roomful of accountants, and they were so down-to-business -- why are economist so different. I said, because accountants are paid to the job done, economists are paid to have an opinion.:)
"If all the economists in the world were laid end to end, they wouldn't reach a conclusion."
What happens if the actual computer and network equipment at each location is grounded there? You've just run 90 volts into an Ethernet port.
And if you don't ground the computer at the other end and it's referenced to the data line, someone touching the computer could get 90 volts through them. Whatever you do, you've got to be careful, and eliminating the possibility of 90-volt differentials (perhaps by running heavy copper braid along the route of the cable and grounding that instead) would appear likely to help (so would eliminating the currents which cause the 90-volt differentials). Just don't allow the possibility of ground currents running through your data wiring.
If you are restricted to a given ERP, you would not be able to increase the field strength at the receiver by using a smaller antenna and more power; all you would do is cover more area with your signal (and create more potential for interference). Plus, you have the expense of TWO antennas... it makes much more sense to use a bigger dish and reduce transmit power to remain legal, because you can squeeze a lot more out of the spectrum that way. (Sometimes the rules actually do make some sense.)
If you are looking for water in New Jersey, you might be better advised to collect and filter rainwater. Solar distillation is inefficient when sunlight levels are low or the weather is cool or cold. However, most places with serious fresh-water deficiencies tend to be warmer and have plenty of sun.
Without a garden of some kind you aren't going to be able to have salad greens more than a few days out, or fresh vegetables more than a few weeks out. That may not be important to you, but sooner or later the mass-budget of stored food exceeds what you'd need for a garden to supply at least part of your needs. And if there's anything you ought to know before spouting off your mouth about space travel, PUSHING MASS AROUND THE SOLAR SYSTEM IS EXPENSIVE!
Look at "Direct Use of the Sun's Energy", by Farrington Daniels. You may be able to find it used, or at the library. (Would you believe a 6000 gallon/day still to purify brackish water? It was done in Chile almost a century ago; you are way behind the times.)
is the term you are looking for. Fuel is apparently still too cheap to make them worthwhile for things like cars; people would rather pay for the extra gas. AFAIK, even heavy trucks are still not using turbocompounding to squeeze the extra few percent out of their diesels. This is odd, because I read about Caterpillar designing a near-adiabatic diesel with turbocompounding around a decade ago, yett there's nothing on the market (but at least they're talking about it).
Solar PV panels run up to about 14% efficiency, whereas Peltier junction devices run maybe 5%? If you're able to build 3 times as much area of collector for the same price, and you're willing to put up with the efficiency going up and down along with the rate of heat input (output voltage is proportional to the temperature difference, so you will have very low voltage and thus low power when the sun is low in the sky)... I suppose it might be worth it. I suspect (educated guesswork) that if you run the numbers you'll find that other approaches are more worthwhile.
What do you mean, "reverse"? The heat-into-voltage trick is exactly what people have been doing with thermocouples for over a century. It's grossly inefficient, but when you are just measuring temperature or only need a little juice and have a relatively large amount of heat to play with (say, like the pilot flame on a gas furnace), it's perfect.
These guys have nothing new. If they really wanted something to crow about, they'd produce something like a small vapor turbine running on butane and try to get 12% efficiency out of the thing. If they could spin one of those on fluid bearings a la the people making microturbine generators, it should be just as reliable and quiet.
The only reason to make a big policy flap about it is political posturing, because policy cannot affect the problem.
Wow! You not only know what the problem with the person doing this and the social context that surrounds him, but have a general theory of sociology that allows you to make proofs!
No, much simpler than that. Policy already outlaws just about everything that the shooter is doing (murder, discharge of a firearm in a populated area...). It's blatantly obvious to anyone who cares to think about it that the shooter just doesn't care about the law. Once someone is gone that far, you're beyond what deterrence can do.
But turn it around. If this case (or another one) would have turned out so that lives were saved by ballistic fingerprinting, would you then favor the law?
Maybe, but only if:
The law really saved lives, rather than just shuffling casualties from one category (a handful of victims of a serial killer) to another (thousands of victims of street thugs), and
The law was written in such a way that it could not be used as a backdoor to a violation of the people's rights (which would take some doing).
That last is the real problem, because the history of such laws is littered with abuses. When you get down to it, the old adage "People who trade essential liberty for a little temporary safety, will have neither liberty nor safety" has been proven true too many times in history. I'd rather look after my own safety than have Leviathan make tradeoffs which will inevitably favor the well-connected over me and mine (e.g. Diane Feinstein favoring gun control for everyone else but concealed-weapons permits for herself).
Well, sorta, but there is nothing magical about 2.4Ghz. It's not the "frequency that water resonates at", as I've even seen printed in semi-credible places.
I've read about ham radio operators cooking hamburgers in resonant cavities at 144 MHz.
The "magical" thing about 2.45 GHz is that it's in the middle of one of the ISM (Industrial, Scientific and Medical) bands designated by the FCC. Since there are no licensed radio services right around there and any un-licensed service has to accept any interference it gets (you can't complain to the FCC that your neighbor's microwave interferes with your 2.45 GHz portable phone), everyone's microwave oven operates at 2.45 GHz.
Spoken like somebody who doesn't live in the area. Or any area where random gun violence is a problem.
The effects on the people in the DC are substantial, wide-ranging, and will be long-lasting.
My area has far greater gun availability, due to less paranoia by the lawmakers, than the DC area. I can even get a concealed-weapons permit if I so desire (I haven't bothered yet). Yet this problem is affecting the DC area. Know what conclusion I draw from this? The gun laws didn't prevent it, and "stronger" ones would only harass the law-abiding. (And yes, I stay away from areas with lots of gun violence, like I stay away from dark alleys and groups of scruffy-looking people.)
I'm smart enough to realize that the chances of dying from a shooter such as this are very small. If I lived in the DC area, I'd exercise more than regular caution until he's caught, but other than that I wouldn't do anything; other factors, including some which are much more within my control, determine the vast majority of my odds of dying in the next week. Once the shooter is out of commission (and he's going to get caught), the added risk goes back to zero. The only reason to make a big policy flap about it is political posturing, because policy cannot affect the problem. Heck, the shooter may have bought the gun from a thief, and all the ballistic fingerprinting in the world wouldn't make it any easier to find him. What then, will you say "Oops, the premise behind this law is a mistake and this will only add to our public expenditures without improving safety, so let's forget the idea"? C'mon, be honest here: would you, or wouldn't you?
You completely missed my point that it wasn't the gun control laws themselves that kept gun violence low, but rather the low numbers of guns in the population.
Like the low number of guns in Switzerland, where every able-bodied male is a member of the reserves and has a battle rifle at home? The assertion is as ridiculous in general as it is in the USA, where rural areas with high levels of gun ownership (and, not coincidentally, high levels of acceptance of guns and a culture of gun safety) have relatively low levels of violence of most kinds, whereas the gun-controlled cities are the centers of all kinds of violence.
More to the point, the same events which led to the influx of ex-Soviet weapons into the rest of the world also led to a flood of people, including Russian Mafiosi. Poor people in general have higher crime rates than middle-class people (see the complaints of the French about e.g. Algerian immigrants bringing crime to the places where they settle). You've latched onto one factor as the cause, and the entire argument is fatally flawed.
So whatever limits these numbers should help lower gun violence.
Uh, yeah. Do you really think that if we get rid of the GUN violence everything will be peachy-keen? Stop assuming that violence with knives, clubs or fists is harmless to its victims. The rate of violent crime in Britain is very high, with a rate of "hot" burglaries which ISTR is higher than the USA's total burglary rate. People get attacked and sometimes killed in such crimes, and it is a moral outrage to demand that they be disarmed so that the criminals won't become "gun violence statistics".
Coincidentally shooting deaths in Europe overall were also about two orders of magnitude lower than in the US, despite an overall larger population. This changed quite dramatically after the Iron Curtain came down and the black market was flooded with Eastern Block military weapons.
Okay. How exactly did the much-touted gun control laws of Europe prevent this from happening? Oops, it happened regardless! (And how much of that was due to the flood of economic refugees out of the ex-Soviet Bloc, as opposed to mere hardware? Consider demography.)
Something you might want to research is the historical rates of violence vs. the relative novelty of gun-control laws. ISTR that Britain's murder rate was an even smaller fraction of the USA's in the 19th century, and that was when Sir Arthur Conan Doyle was writing about Sherlock Holmes carrying a pistol whenever it suited him (not just unregistered weapons, but legal unrestricted concealed carry!). Attributing the historical crime statistics in those states to their present-day gun-control laws puts the effect before the cause.
It was being debated some time ago that taggants be added to all gunpowder, to prevent it from being used in home-made bombs. The taggants being proposed were like chips of paint off an old house, layers of different colors yielding a unique "bar code" for each batch; they also had UV-fluorescent and magnetic layers to make them easy to find in the debris. Congress was holding hearings on the issue, and one of the opponents took some of the tagged powder and just swept it with a magnet to get the magnetic particles, then picked out the fluorescent ones with a hand-held blacklight and tweezers. Before the end of the hearing he had a pile of powder on one side and a much smaller pile of tags on the other.
Good thing Congress listened to reason that time; the taggants would have really made it hell for black-powder shooters, not to mention the absurd expense of marking and tracking every batch of Pyrodex. I hope Congress is still able to listen to reason.
I'm sorry, but I think that if you really believe this:
This point is to provide a starting point for investigators, and create doubt in the minds of criminals.
... you are more than a little gullible. Criminals most often use guns to coerce people rather than to shoot them, and the thought of being traced down by the markings on the copper jacket or the spent brass is just too far ahead of their thinking to matter. (A criminal who buys a stolen gun out of someone's trunk is probably right to ignore it completely.) Then you have the fact that barrels and such are made on one or a very small number of broaching machines, and are very very similar to one another (else they would not be interchangeable parts)...
If you are trying to decide if the same gun was used in a number of similar crimes, such fuzziness is okay because the chances of having an accidental match are small. But if you start comparing against the entire population of guns in a particular caliber, you've got a problem.
No, the avowed purpose doesn't pass the smell test (except to cranks like Charles Schumer, who never saw a gun-confiscation law he didn't like). Instead, consider that this law wouldn't work without a comprehensive registry of guns and their owners. This would make it trivial to confiscate (a la NYC) everyone's guns, or just throw the protesters in jail for having failed to register their sale (or report their loss/theft to the appropriate authorities). Think it can't happen? It has already happened, in the USA, in several places.
No, there was no effect on crime. So-called "assault weapons" or "sniper guns" are used in a vanishingly small fraction of crimes. How many people died in traffic accidents in the Washington DC metro area during the last two weeks? How many people died in falls? As a public-health problem or a public-policy problem, this isn't worthy of any action; it is purely a police matter. That won't stop some demagogues from claiming that their law is EVEN BETTER THAN SNAKE OIL!, nor will it prevent a huge pile of idiots from voting for said pol on that basis. (When the voters start throwing out such pols for insulting their intelligence, we might have a sane and sensible government after a few elections. I give this about a snowball's chance in hell.)
I hate to burst your bubble, but having people do their job for the benefit of society is a hallmark of socialism, and has been conclusively proven not to work, except under very special conditions. If there was no money to be made from writing books, very few would write them.
I don't mind bursting your bubble. If the laws of society are to exclusively benefit one group of people over another, why should the latter group bother to obey them? The point of copyright law is that it strikes a bargain for the benefit of all, not that it creates a sinecure for authors, artists and the CEOs of megamedia conglomerates.
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There was another company looking to piggy-back on the National Weather Service's twice-daily balloon sounding probes to provide cellular service in unserved areas. The latex balloons climb to extreme altitudes, and then often hang for 24 hours or more without moving much (according to the article) before bursting. If the relay balloons float at similar altitudes, they would require little power for stationkeeping.
Big deal, you bar air traffic from the area. We may soon be doing the same to generate electricity, with tethers perhaps 3 miles long; check out gyromills for a jolt to your weltanschauüng. Have you looked at the balloons used to loft cosmic-ray, infrared and the cosmic-background radiation experiments lately? Boomerang flew at 120,000 feet, thus requiring a balloon several times the volume required to loft a payload to a mere 65,000 feet. There is a lot of established expertise, and while this can't be considered a trivial exercise it isn't going to require much new work.My speculation:
What chance does an unaugmented human have against such an apparatus?
I doubt that the police agencies will find this outfit to be a joke; I think they'll call it criminal fraud.
I was also very pessimistic. At 50,000 megawatt-days per ton over 730 days burn time (roughly 68 megawatts average) and 4 megawatt-days to achieve orbit, the fuel would produce the energy to loft itself in about an hour and a half. It would produce the energy to put itself onto an escape trajectory in about three hours.
Typical "burnup" for nuclear fuel in commercial pressurized-water reactors (PWRs) is something on the order of 50,000 megawatt-DAYS per ton. A megawatt-day is 86.4 gigajoules. You could produce the energy to throw the fuel into orbit in 4 days; escape velocity would take 8 days. And that's assuming you don't do anything intelligent like reprocessing the fuel so you only have to dispose of the actual fission products (you can keep the leftover uranium and plutonium and throw them right back into the reactor); if you reprocessed, you would only need to get rid of 10% or less of the total fuel mass per cycle. A load of fuel lasts a couple of years. All in all, you are talking about 1% of the energy output of the fuel to send it all away from Earth after you're done.
This is not to say that it would be smart to do that if you could, or that the engineering required would be feasible even if it was smart. But nothing in the energetics prevents you from doing so.
... the influence of synthetic hormones on wildlife is threatening aquatic species by feminizing males. (No, those hormones are not rendered inactive either by the body or by sewage-treatment plants.) Latex, so long as you aren't allergic to it, at least has the benefit that it's biodegradable.
If you are restricted to a given ERP, you would not be able to increase the field strength at the receiver by using a smaller antenna and more power; all you would do is cover more area with your signal (and create more potential for interference). Plus, you have the expense of TWO antennas... it makes much more sense to use a bigger dish and reduce transmit power to remain legal, because you can squeeze a lot more out of the spectrum that way. (Sometimes the rules actually do make some sense.)
If you are looking for water in New Jersey, you might be better advised to collect and filter rainwater. Solar distillation is inefficient when sunlight levels are low or the weather is cool or cold. However, most places with serious fresh-water deficiencies tend to be warmer and have plenty of sun.
Without a garden of some kind you aren't going to be able to have salad greens more than a few days out, or fresh vegetables more than a few weeks out. That may not be important to you, but sooner or later the mass-budget of stored food exceeds what you'd need for a garden to supply at least part of your needs. And if there's anything you ought to know before spouting off your mouth about space travel, PUSHING MASS AROUND THE SOLAR SYSTEM IS EXPENSIVE!
Look at "Direct Use of the Sun's Energy", by Farrington Daniels. You may be able to find it used, or at the library. (Would you believe a 6000 gallon/day still to purify brackish water? It was done in Chile almost a century ago; you are way behind the times.)
is the term you are looking for. Fuel is apparently still too cheap to make them worthwhile for things like cars; people would rather pay for the extra gas. AFAIK, even heavy trucks are still not using turbocompounding to squeeze the extra few percent out of their diesels. This is odd, because I read about Caterpillar designing a near-adiabatic diesel with turbocompounding around a decade ago, yett there's nothing on the market (but at least they're talking about it).
Solar PV panels run up to about 14% efficiency, whereas Peltier junction devices run maybe 5%? If you're able to build 3 times as much area of collector for the same price, and you're willing to put up with the efficiency going up and down along with the rate of heat input (output voltage is proportional to the temperature difference, so you will have very low voltage and thus low power when the sun is low in the sky)... I suppose it might be worth it. I suspect (educated guesswork) that if you run the numbers you'll find that other approaches are more worthwhile.
These guys have nothing new. If they really wanted something to crow about, they'd produce something like a small vapor turbine running on butane and try to get 12% efficiency out of the thing. If they could spin one of those on fluid bearings a la the people making microturbine generators, it should be just as reliable and quiet.
- The law really saved lives, rather than just shuffling casualties from one category (a handful of victims of a serial killer) to another (thousands of victims of street thugs), and
- The law was written in such a way that it could not be used as a backdoor to a violation of the people's rights (which would take some doing).
That last is the real problem, because the history of such laws is littered with abuses. When you get down to it, the old adage "People who trade essential liberty for a little temporary safety, will have neither liberty nor safety" has been proven true too many times in history. I'd rather look after my own safety than have Leviathan make tradeoffs which will inevitably favor the well-connected over me and mine (e.g. Diane Feinstein favoring gun control for everyone else but concealed-weapons permits for herself).The "magical" thing about 2.45 GHz is that it's in the middle of one of the ISM (Industrial, Scientific and Medical) bands designated by the FCC. Since there are no licensed radio services right around there and any un-licensed service has to accept any interference it gets (you can't complain to the FCC that your neighbor's microwave interferes with your 2.45 GHz portable phone), everyone's microwave oven operates at 2.45 GHz.
Think of the possibilities for carving stone without cracking it. This could make it a lot easier for sculptors.
I'm smart enough to realize that the chances of dying from a shooter such as this are very small. If I lived in the DC area, I'd exercise more than regular caution until he's caught, but other than that I wouldn't do anything; other factors, including some which are much more within my control, determine the vast majority of my odds of dying in the next week. Once the shooter is out of commission (and he's going to get caught), the added risk goes back to zero. The only reason to make a big policy flap about it is political posturing, because policy cannot affect the problem. Heck, the shooter may have bought the gun from a thief, and all the ballistic fingerprinting in the world wouldn't make it any easier to find him. What then, will you say "Oops, the premise behind this law is a mistake and this will only add to our public expenditures without improving safety, so let's forget the idea"? C'mon, be honest here: would you, or wouldn't you?
More to the point, the same events which led to the influx of ex-Soviet weapons into the rest of the world also led to a flood of people, including Russian Mafiosi. Poor people in general have higher crime rates than middle-class people (see the complaints of the French about e.g. Algerian immigrants bringing crime to the places where they settle). You've latched onto one factor as the cause, and the entire argument is fatally flawed.
Uh, yeah. Do you really think that if we get rid of the GUN violence everything will be peachy-keen? Stop assuming that violence with knives, clubs or fists is harmless to its victims. The rate of violent crime in Britain is very high, with a rate of "hot" burglaries which ISTR is higher than the USA's total burglary rate. People get attacked and sometimes killed in such crimes, and it is a moral outrage to demand that they be disarmed so that the criminals won't become "gun violence statistics".Something you might want to research is the historical rates of violence vs. the relative novelty of gun-control laws. ISTR that Britain's murder rate was an even smaller fraction of the USA's in the 19th century, and that was when Sir Arthur Conan Doyle was writing about Sherlock Holmes carrying a pistol whenever it suited him (not just unregistered weapons, but legal unrestricted concealed carry!). Attributing the historical crime statistics in those states to their present-day gun-control laws puts the effect before the cause.
Good thing Congress listened to reason that time; the taggants would have really made it hell for black-powder shooters, not to mention the absurd expense of marking and tracking every batch of Pyrodex. I hope Congress is still able to listen to reason.
If you are trying to decide if the same gun was used in a number of similar crimes, such fuzziness is okay because the chances of having an accidental match are small. But if you start comparing against the entire population of guns in a particular caliber, you've got a problem.
No, the avowed purpose doesn't pass the smell test (except to cranks like Charles Schumer, who never saw a gun-confiscation law he didn't like). Instead, consider that this law wouldn't work without a comprehensive registry of guns and their owners. This would make it trivial to confiscate (a la NYC) everyone's guns, or just throw the protesters in jail for having failed to register their sale (or report their loss/theft to the appropriate authorities). Think it can't happen? It has already happened, in the USA, in several places.
No, there was no effect on crime. So-called "assault weapons" or "sniper guns" are used in a vanishingly small fraction of crimes. How many people died in traffic accidents in the Washington DC metro area during the last two weeks? How many people died in falls? As a public-health problem or a public-policy problem, this isn't worthy of any action; it is purely a police matter. That won't stop some demagogues from claiming that their law is EVEN BETTER THAN SNAKE OIL!, nor will it prevent a huge pile of idiots from voting for said pol on that basis. (When the voters start throwing out such pols for insulting their intelligence, we might have a sane and sensible government after a few elections. I give this about a snowball's chance in hell.)