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Re:WiFi works in: by tibit · 2011-05-09 14:44 · Score: 1 · on Global Warming To Hinder Wi-Fi Signals, Claims UK Gov't

Unless we're talking about using WiFi for tower-to-cantenna style paths, WiFi is pretty much insensitive to absorption in air. To a point where I bet we could easily have 95% humidity at 10 atmospheres and there'd be no noticeable effect on propagation. In satellite communications, clear air (whether humid or not) absorbs a couple dB. So whatever is done by air in a building can be neglected, even if it was an order of magnitude or two more intense. WiFi signals from antennas with low directionality (as is the case with usual access points) are lost to building materials and to free space path loss (20dB power loss per decade of increase in distance). Interference from other sources in the ISM band causes additional degradation of SNR. And that's pretty much it.

Re:Where have all the good people gone? by Anonymous Coward · 2008-08-14 04:05 · Score: 0 · on Rat-Brained Robots Take Their First Steps

http://www.nsti.org/Nanotech2008/symposia/Nanotech_Neurology.html

http://www.bci-info.tugraz.at/bibliography_view

http://www.wtec.org/bci/workshop/01_Berger_Intro.pdf

Required steps:

Manufacture a micro-electrode array (pretty easy at this point)

Culture neurons (also doable)

Get the neurons to stick to the array in an orderly manner (this part is tricky: either they don't adhere, they adhere and die, too many adhere to one electrode and the clumps give a messy signal, etc.)

Wait a couple days and the neurons start firing (a crap shoot, sometimes they croak, get a bio guy to nurture them good)

Make sense out of the noisy signal (tough, the time scales on the signals is pretty quick)

Stimulate some neurons, see what the network response is (doable if all the previous steps worked perfectly)

Problems:
Power (TFA used 110V out of the wall and a robot battery; not as useful for inside a patient's skull)

Communications (RF-MEMS is still a work in progress)

A useful product would be a network of invasive implants that don't cause (much) damage at the implant site and don't lose function over time. Link these to a logic module (outside the brain, but maybe inside the body or skull) that makes sense of the input and can tell the actuators what to stimulate. I think you'll need the logic module outside the invasive implant because you just don't have that much volume to play with in the implant.

I hope this leads to fruitful stuff. I wasn't very successful at it because my EE wasn't good enough to do the signal processing, my bio wasn't good enough to keep neurons happy or even alive, and I didn't much like working 80 hours/week for $12k/yr. I was good at the wet bench fab and wiring though...

It's been a long time by turtledot · 2005-04-04 06:48 · Score: 0 · on Hitachi Predicts 3D Hard Disks by Year's End

Sure took a long time. The concept of perpendicular recording is relatively old - I remember work being done on it back in days when Microsoft was a cute little monkey. Here is a nice link that explains the process: http://www.wtec.org/loyola/hdmem/02_03.htm/ Intel has a note on it - no date, but this is for floppies... http://support.intel.com/design/archives/periphrl/ docs/7281.htm Toshiba is working on this technology: http://www.nwfusion.com/news/2004/1214toshitous.ht ml/ The technology was used in tapes in 2002: http://www.internetnews.com/storage/article.php/15 01631

Flat Panel Displays FPD's by vigour · 2005-02-23 09:59 · Score: 1 · on Dell Enters HDTV Market with Plasma Display

LCD's are still the most common FPD for many reasons including size, power consumption, contrast ration, brightness, and the fact that it's the most mature of the "new" display technologies (back in the 80's Japan became the world leader in LCD development).

The manufacturing process has progressed to a point where manufacturers consider only 3/4 pixels in a 32" display to be defective. The only major drawbacks to LCD's at this stage are response speed (fast moving images can get a little blurred), and their viewing angle.

There's a phenomenal amount of research going on into solving these problems, especially the viewing angle (something I was involved in myself indirectly). Even back in '98 companies like Mitsubishi had prototypes (.pdf) that outperform current commercial displays.

HDTV CRTs still outperform HDTV LCDs, but in for ordinary TVs LCDs have superior quality in terms of things like definition, image clarity, contrast ratio, so at this stage if you're after HDTV you really should stick with CRTs (unless you're prepared to wait another few years

Damn, too sleepy to finish this....... :P

Re:Loons? Patriot II passed, try DNA by tail.man · 2004-12-10 10:18 · Score: 0 · on Driver's Licenses with Digital Watermarks

You may be correct.

I think we agree more than disagree.

My point is that regardles of the legal details the end result is that if you don't have the number and the card you are a non person. If the legal details are not in place now, wait for patriot III.

Next comes the chip...
NSF report on merging humans and technology. The hive mind is mentioned. (PDF)

They want to chip us all. These things can do more than identify you. The new models can track you and RECEIVE transmissions. Don't take the chip.

Re:MSCFB by The+Master+Control+P · 2004-09-14 16:53 · Score: 3, Informative · on Wind Power Falls Under $0.01/kwh

Scientists have already experimented with them; They mount a high-strength centrifuge onto a superconductor for levitation, and place it into a vaccuum. Right now, I think there are a few test units in place. Link. I think that Superconducting Magnetic Energy Storage is more interesting; They store energy by building an enormously powerful magnetic field around a superconducting toroid. The neat thing is that, minus losses from cooling, the energy is stored for basically ever.

some current research and conjecture... by asreal · 2004-07-25 17:02 · Score: 2, Informative · on The Internet Meets the Neural Net

is available here. one of the most promising techniques seems to be self-assembling nanowires and sensors running through the blood vessels of the brain. lots of facinating reading.

Re:Field Strength by SamSim · 2004-01-15 03:37 · Score: 2, Interesting · on Chinese MagLev Train Opens Next Week

5.3 teslas apparently. (A tesla is a relatively large unit of magnetic flux density.) By comparison the Earth's natural magnetic field, the one that makes your compass turn, is ~0.00005 teslas.