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Bees Communicate With Electric Fields 133

Posted by samzenpus
from the buzz-of-buzzing dept.
sciencehabit writes "The electric fields that build up on honey bees as they fly, flutter their wings, or rub body parts together may allow the insects to talk to each other, a new study suggests. Tests show that the electric fields, which can be quite strong, deflect the bees' antennae, which, in turn, provide signals to the brain through specialized organs at their bases. Antenna deflections induced by an electrically charged honey bee wing are about 10 times the size of those that would be caused by airflow from the wing fluttering at the same distance—a sign that electrical fields could be an important signal."

Comment: Re:Everyone else uses H264/MPEG4 (Score 3, Informative) 336

by sadtrev (#34855066) Attached to: Opera Supports Google Decision To Drop H.264

still-image compression is not a field where large gains can be had so easily.

JPEG has two significant practical deficiencies which are not inherent in its lossy nature

  • firstly it's 8-bit channel depth is not enough to allow any editing without noticeable degradation,
  • and secondly, its compression characteristics tend to enhance photo grain and silicon array noise.

I guess that the reason that something better hasn't emerged is the combination of the patent thicket around wavelets, and all the shenanegans the digital camera manufacturers have been playing with raw formats.

Comment: Re:Should be reliable (Score 5, Interesting) 334

by sadtrev (#33756980) Attached to: Jaguar's Hybrid Jet-Powered Concept Car
The Rover gas-turbine car was almost ready for launch (in the mid-'60s). It was cleaner, quieter and potentially cheaper than cars with conventional reciprocating engine designs.
It did have two major disadvantages - unreliability due to brittleness of the heat exchanger, and
- the tendency to singe the paint off cars that approached too close to the exhaust.

Comment: What is the data? (Score 2, Interesting) 137

by sadtrev (#32085674) Attached to: "Digital Universe" Enters the Zettabyte Era

I was told about 10 years ago that "70% of the world's digital data is stored under MVS" which surprised me a bit, even then.
After some thought when you consider that almost all commercial transactions (banks, telcos etc) whould have been running MVS then it may have been true.
SETI and CERN and other large scientific endeavours are small fry in comparison.

Comment: Re:Especially since someone has implemented it.... (Score 4, Insightful) 334

by sadtrev (#32070004) Attached to: MATLAB Can't Manipulate 64-Bit Integers

using 64-bit integers instead of floats is a common trick in embedded C for control and signal processing on low power processors. I have experience of four different embedded systems used in commercial products from three different companies I've worked with - three of the four used 64-bit integers for roundoff-sensitive calculations.
I was a bit surprised that Matlab can't handle this, but then I've seen the poor quality of the ostensibly production-ready code that comes out of their M2C converter - it was about ten times the code footprint and a fifth the speed of a minimally-optimised C version of the same algorithm.

Honestly, I don't know how anyone can justify paying for this, when R (and even Octave in this instance) is more capable. Where the target platform requires C or asm code, then doing development in Matlab is usually more trouble than it saves. The graphs are prettier, though.

Comment: Re:I don't worry much about paper (Score 1) 446

by sadtrev (#31996470) Attached to: Paper Manufacturer Launches "Print More" Campaign

These days paper, as is used in laser printers etc. is not made mostly from wood. It is mostly made from bulking agents like calcium carbonate, which have to be ground to typically 2 micron or finer, and then dried at huge energy cost.
The wood fibers are just there to keep all the bulk together, and are a small portion (sometimes as little as 10%) of the weight of a sheet of paper.

You may have noticed that this sort of paper leaves a lot of ash when burnt.

Comment: Re:Use a disposable laptop (Score 4, Informative) 249

by sadtrev (#31643014) Attached to: Rugged Laptop/Tablet Suggestions, 2010 Version?

Fine sand is a killer - it gets everywhere.

I used to work on powder processing instrumentation and regularly had to take laptop computers onsite to calibrate instruments. We used to use Dells with external IP-54 keyboards and masking tape over all the unused ports. On a few occasions I had to take a normal keyboard they didn't last more than a few keystrokes (I'd guess 20 per key before they failed).

This was lactose, coal, silica, calcium carbonate, etc. When we started work with metal powder we invested in proper IP54 laptops - no fan, membrane keyboard and rubber plugs on all the ports. Heavy, underpowered (800MHz PIII) but they worked. We looked at some "ruggedised" efforts but without the IP rating they were really just slightly less prone to drop damage.

Comment: Re:It'll stop in a few years (Score 1) 721

by sadtrev (#31356524) Attached to: Using Classical Music As a Form of Social Control
The good bits of "Mozart's Requiem" were written by one of his students after he died in order to help pay his debts.

The only other half-decent stuff attributed to him are the 40th Symphony and the Magic Flute overture, also written in the three months whilst he was kicking the bucket. Makes me suspect that somebody else wrote them for him as well.


BlackBerry Bold Tops Radiation Ranking 189

Posted by timothy
from the woo-top-of-the-list-awesome dept.
geek4 writes with this excerpt from eWeek Europe: "Data from the Environmental Working Group places the BlackBerry Bold 9700 as the mobile device with the highest legal levels of cell phone radiation among popular smartphones. Research In Motion's BlackBerry Bold 9700 scores the highest among popular smartphones for exposing users to the highest legal levels of cell phone radiation, according to the latest 2010 Environmental Working Group ranking. Following the Bold 9700 are the Motorola Droid, the LG Chocolate and Google's HTC Nexus One. The rankings still put the phones well within federal guidelines and rules."

Comment: Re:US vs UK... (Score 5, Interesting) 1174

by sadtrev (#29984300) Attached to: Plug vs. Plug — Which Nation's Socket Is Best?

Having lived in the US, UK, Malaysia and France, I would concurr that the British plug system is far better. It was properly thought, and universally implemented across the country 50 years ago using an act of parliment on the premise that using anything else was dangerous and therefore potentially negligent. More features have been added since then (including household earth-leakage trip sensing).

I've had problems with a French pin snapping in a socket leaving an exposed live pin for my 3-year-old son to play with (luckily I spotted it in time and managed to cover it).
In the US I almost got used to the risk of shocks off electrical appliances. I also had a lab fire destroy some of my work because somebody had knocked out the cable of the pump supplying the coolant.

In Malaysia where the national standard specifies the british plug type, the biggest issue was that cheap Chinese imports sometimes didn't use it.

When basic safety is involved, I don't think that it's over-engineering. Your comment about extra points of failure doesn't make any sense.

To downgrade the human mind is bad theology. - C. K. Chesterton