20mm wavelength seems to be 17KHz (at sealevel in air), which isn't very "ultra" sound. To levitate the 3 meters radius of adult humans (with extended arms/legs), we'd need 6m wavelength.Which is about 57Hz.
How much power...well lots. Area of human (one side) about 1sq. m. mass, (order of magnitude) 100Kg, say 1KN force required = 1Megapascal.
That's 10bar pressure, implying an acoustic pressure of 10dB above atmospheric..or 203dB into 4pi space.
Imagine you had a 'regular' hifi speaker, radiating into half space..and that it behaved in a perfectly linear manner to power input (no chance!) at the typical 1% efficiency of electrical-to-acoustic conversion, you' need to hit it with, oh, about a half megawatt. Really. Which means poor sorry-assed-but-levitated-human falls apart.
(assumptions: 87dB/watt for reasonable speaker; +3dB gain for half-space; power required = 10^ [(200-87)/20] )
...if there is some way to harness the GPU as an add-on vector processor, it could get very interesting.
Now - I'm just an end-user, sitting here working with a large project in Revit, an application that brings even fast PCs stacked with RAM to their knees. It's basically a database with a graphical interface and so every little operation results in refreshes and an element of regeneration of the display. It's a good tool, with great potential, yet that lag is a total patience-killer.
If the vector operations which all that rendering must involve could be usefully offloaded to a videocard well-stocked with RAM however... our little company would buy dozens today.
The problem boils down to the fact that people with a digital hammer view everything as a nail, when it aint necessarily so.
The is an enormous space left over for a really good analoguesqueeelccch and farty noise; but...too many think that that it's a given that everything is already, or can be, modelled (usu. in terms of amplitude) - and the rest is some sort of artifact.
Sorry to disillusion people people , but as an real [not-fucking-software;) ] Architect (or even anarchi-tect) these thing are the way forward.
In the UK we call such systems BMS, Building Management Systems. It amounts to vaguely-intelligent way to manage building energy consumption; that is the sole remit. Realise that, while there may be ways to access the info remotely and thus expose the system to security risks.that is not the prime objective
The real point is to monitor boiler firing cycles, and window-openings (night-purge cooling etc) remotely to minimise running cost.
Yes, it's great. I can watch, in real-time , the window management of a school I designed two years ago, from a terminal 200 miles away. I can learn from it, in terms of how the building is really used, as opposed to how it was assumed to work. Can I over-ride choices? No, and neither can any one else by 'hacking' the system. The truth is, BSMS systems are dumb - they are pre-programmed and (at best) report. No-one (esp. the investors) is actually interested in spending for IP addresses for the windows on the Arts wing, the necesary actuators and so on. I can monitor these things only because the necessary sensing is already part of other systems - like the alarm systems.
To everyone who wants to set off the sprinklers at their High School: please realise that sprinkler heads are purely reactive and work solely on rate-of-rise of temperature; they are not remotely addressable. Smoke sensors, on the other hand, can be;)
Brick mobiles were that size because the analogue design didn't lend itself to the ASIC design behind modern mobiles. The output power BTW was of the order of 100mW.
Time change, and cometh the mass market, and digital transmission; the result is a tiny phone which delivers 1W+ RF output. Impressive, no?
Either way the real issues are these:
1) Consider the inverse-square law, and therefore the effective dose of 1W of RF very, very close to the skull. and also 2) Showing that such non-ionising radiation is actually deleterious.
Hint: the second point is not exactly a straightforward task.
It's frequently observed as a ghostly blue light in the deep water holding tanks for freshly-spent fissile material from nuclear reactors. Some of the active particles travel faster than the speed of light in the water, leading to the Cerenkov effect.
..irelies on a miniturised Reality Distortion Field which diverts the hot air into the Marketing division.
A less sarcastic answer - it has to be a proc. revision or variant which lowers power demand. In a portable, waste heat is wasted battery life. Apple laptops excel at battery life/ management - I would be amazed if that got tossed just to get to market.
Using the revised estimate of 1750000million tonnes, and guessing a nice slow drift rate of 0.1ms^-1, how much kinetic energy is involved?
= 0.5 * 1.75*10^15 * (0.1)^2 = 17.5TJ (!)
That's a metric shedload, but it will be released over a few days. Once the thing comes to rest I think we can reasonably expect a new range of ice hills, rather than a billion par-boiled penguins.
There once was a man, whose name 'Blunkett.' Caused a limerick-composition junket But feeding the troll, however droll, Is the norm on Slashdot - who'dathunkit?
Anyone who does graphic or presentation work knows such tech is already built into large-format colour printers.
These things are actually dimly sentient, and cantankerous to boot. I swear they know when you're under pressure from an immoveable deadline. That's when they chose to break down/clog heads/eat your last sheets of glossy presentation material at 5am / have the driver b0rk...
It's true. Divide and Conquer was the way to get things done, and the peoples who became the British learnt well from the Roman example followed basically by about 800years of small kingdoms with internecine warfare on a small island. We're a melting-pot which bred a very pugnacious people (ever wondered what soccer violence is about? it's displacement in action...).
Interesting then, that with respect to quelling violence in the power vacuum following the invasion, the (underresourced, as ever) British forces seem to have had much more success in Southern Iraq than the Americans in the North. I'd put this down to experience basically - all the technology in the world doesn't matter a jot, it's all in choosing appropriate tactics. A long history of dealing with insurgency (as an invading power) and most recently the 35+ years of the IRA taught a lot when it comes to dealing with urban guerilla action.
(Yes, I am a Brit, and while I don't agree with suspect motives behind the Joint Forces' actions in Iraq, I am damn proud of the achievements of our boys on the ground. They deserve our support for being on the shitty end of a thorny stick)
More examples
on
Solar Shingles
·
· Score: 3, Informative
This sort of thing has to be the way forward. A lot of work has been put into the field in the last 15-20 years, and now economies of scale are steadily bringing the costs down to reasonable. Five years ago, costs for PV panels were around the $10-12 per installed watt; today it's more like $7. We're getting there.
Best of all, it's a fit-once solution that will last as long as any other material might be reasonable expected to, off-setting energy demand all the while. Oh, and the colour is a rather fetching blue-violet depending on where you view it from:)
Here's a few more examples:
Research on photovoltaics in cladding systems done here in the UK at Southampton Uni.
The German cladding manufacturer Schüco has a variety of well-developed photovoltaic cladding systems:
From the article: In the study, which was conducted at Insurance Office of America's headquarters in Orlando, Fla., each of nine workstations was equipped with a miniature personal environment-sensor for sampling air temperature every 15 minutes.
Wow, what a meaningful sample size.
That, and the references to keyboards and accuracy makes it sound like it's purely a study of a typing pool to me. Probably female, probably requiring little in the way of creative/critical thinking, just a cosy space to get on with the tiresome task of earning a dollar.
I rather doubt it - there are just so many divices where CMOS will be the optimal way forward for cost/packaging/process reasons.
Just think of the vast amounts of 'glue' logic used in everything - no point going 'nano' just because we could. Same reason 8-bit cpus are used more now than ever before....
Slashdot Mirror
How much power...well lots. Area of human (one side) about 1sq. m. mass, (order of magnitude) 100Kg, say 1KN force required = 1Megapascal. That's 10bar pressure, implying an acoustic pressure of 10dB above atmospheric..or 203dB into 4pi space.
Imagine you had a 'regular' hifi speaker, radiating into half space..and that it behaved in a perfectly linear manner to power input (no chance!) at the typical 1% efficiency of electrical-to-acoustic conversion, you' need to hit it with, oh, about a half megawatt. Really. Which means poor sorry-assed-but-levitated-human falls apart.
(assumptions: 87dB/watt for reasonable speaker; +3dB gain for half-space; power required = 10^ [(200-87)/20] )
You know, the sort who unthinkingly park 'the kids' in front of the TV/DVD to give themselves a few hours 'freedom'...
Cheers, but we've already set that up - and still the lag bugs us...
Now - I'm just an end-user, sitting here working with a large project in Revit, an application that brings even fast PCs stacked with RAM to their knees. It's basically a database with a graphical interface and so every little operation results in refreshes and an element of regeneration of the display. It's a good tool, with great potential, yet that lag is a total patience-killer.
If the vector operations which all that rendering must involve could be usefully offloaded to a videocard well-stocked with RAM however... our little company would buy dozens today.
...sounds like a job for Nikola Tesla... for which you will need a tin foil ha*bang*fizzz* ~#$£$%&)67~NO CARRIER
The is an enormous space left over for a really good analoguesqueeelccch and farty noise; but...too many think that that it's a given that everything is already, or can be, modelled (usu. in terms of amplitude) - and the rest is some sort of artifact.
Sad but true.
In the UK we call such systems BMS, Building Management Systems. It amounts to vaguely-intelligent way to manage building energy consumption; that is the sole remit. Realise that, while there may be ways to access the info remotely and thus expose the system to security risks
The real point is to monitor boiler firing cycles, and window-openings (night-purge cooling etc) remotely to minimise running cost.
;)
Yes, it's great. I can watch, in real-time , the window management of a school I designed two years ago, from a terminal 200 miles away. I can learn from it, in terms of how the building is really used, as opposed to how it was assumed to work. Can I over-ride choices? No, and neither can any one else by 'hacking' the system. The truth is, BSMS systems are dumb - they are pre-programmed and (at best) report. No-one (esp. the investors) is actually interested in spending for IP addresses for the windows on the Arts wing, the necesary actuators and so on. I can monitor these things only because the necessary sensing is already part of other systems - like the alarm systems.
To everyone who wants to set off the sprinklers at their High School: please realise that sprinkler heads are purely reactive and work solely on rate-of-rise of temperature; they are not remotely addressable. Smoke sensors, on the other hand, can be
*must resist....oh well, fuck it*
In Soviet Russia, ex-commie launches YOU!
Yes, but not for the reason you imagine.
Brick mobiles were that size because the analogue design didn't lend itself to the ASIC design behind modern mobiles. The output power BTW was of the order of 100mW.
Time change, and cometh the mass market, and digital transmission; the result is a tiny phone which delivers 1W+ RF output. Impressive, no?
Either way the real issues are these:
1) Consider the inverse-square law, and therefore the effective dose of 1W of RF very, very close to the skull.
and also
2) Showing that such non-ionising radiation is actually deleterious.
Hint: the second point is not exactly a straightforward task.
..was there all along in a way: Loki is the Norse deity representing deceit and under-handedness: the Sly One, the Trickster, the Shape Changer
It's frequently observed as a ghostly blue light in the deep water holding tanks for freshly-spent fissile material from nuclear reactors. Some of the active particles travel faster than the speed of light in the water, leading to the Cerenkov effect.
..irelies on a miniturised Reality Distortion Field which diverts the hot air into the Marketing division.
A less sarcastic answer - it has to be a proc. revision or variant which lowers power demand. In a portable, waste heat is wasted battery life. Apple laptops excel at battery life/ management - I would be amazed if that got tossed just to get to market.
Using the revised estimate of 1750000million tonnes, and guessing a nice slow drift rate of 0.1ms^-1, how much kinetic energy is involved?
= 0.5 * 1.75*10^15 * (0.1)^2
= 17.5TJ (!)
That's a metric shedload, but it will be released over a few days. Once the thing comes to rest I think we can reasonably expect a new range of ice hills, rather than a billion par-boiled penguins.
X _ X
\
0F0064
The electron ram stabbed out another searing blaze of light and took
out the appendix.
"How do you think I feel?" said Marvin bitterly.
"Just ran off and left you, did they?" the machine thundered.
"Yes," said Marvin.
"I think I'll shoot down their bloody ceiling as well!" raged the tank.
It took out the ceiling of the theatre.
"That's very impressive," murmured Marvin.
"You ain't seeing nothing yet," promised the machine, "I can take out
this floor too, no trouble!"
It took out the floor, too.
"Hell's bells!" the machine roared as it plummeted fifteen storeys and
smashed itself to bits on the ground below.
"What a depressingly stupid machine," said Marvin and trudged away.
(with apologies to Douglas...)
There once was a man, whose name 'Blunkett.'
Caused a limerick-composition junket
But feeding the troll,
however droll,
Is the norm on Slashdot - who'dathunkit?
These things are actually dimly sentient, and cantankerous to boot. I swear they know when you're under pressure from an immoveable deadline. That's when they chose to break down/clog heads/eat your last sheets of glossy presentation material at 5am / have the driver b0rk...
It's the reason we call them plotters
X _ X
\
0F0064
B*4*i (U)^0.5 (RU/18)
( write it out longhand, replacing the power function with regular symbol... )
Interesting then, that with respect to quelling violence in the power vacuum following the invasion, the (underresourced, as ever) British forces seem to have had much more success in Southern Iraq than the Americans in the North. I'd put this down to experience basically - all the technology in the world doesn't matter a jot, it's all in choosing appropriate tactics. A long history of dealing with insurgency (as an invading power) and most recently the 35+ years of the IRA taught a lot when it comes to dealing with urban guerilla action.
(Yes, I am a Brit, and while I don't agree with suspect motives behind the Joint Forces' actions in Iraq, I am damn proud of the achievements of our boys on the ground. They deserve our support for being on the shitty end of a thorny stick)
Best of all, it's a fit-once solution that will last as long as any other material might be reasonable expected to, off-setting energy demand all the while. Oh, and the colour is a rather fetching blue-violet depending on where you view it from :)
Here's a few more examples:
Research on photovoltaics in cladding systems done here in the UK at Southampton Uni.
The German cladding manufacturer Schüco has a variety of well-developed photovoltaic cladding systems:
More European examples
A 60KW solar roof cladding installation in Berkeley, California.
..used that excuse to justify being an alcoholic.
Works for me *hic*
In the study, which was conducted at Insurance Office of America's headquarters in Orlando, Fla., each of nine workstations was equipped with a miniature personal environment-sensor for sampling air temperature every 15 minutes.
Wow, what a meaningful sample size.
That, and the references to keyboards and accuracy makes it sound like it's purely a study of a typing pool to me. Probably female, probably requiring little in the way of creative/critical thinking, just a cosy space to get on with the tiresome task of earning a dollar.
This passes for 'research'...? Oh dear.
It's like, how much more black could the sun be? and the answer is none. None more sunspots.
I rather doubt it - there are just so many divices where CMOS will be the optimal way forward for cost/packaging/process reasons.
Just think of the vast amounts of 'glue' logic used in everything - no point going 'nano' just because we could. Same reason 8-bit cpus are used more now than ever before....