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Comment: not an experimental demonstration (Score 5, Informative) 79

by henryteighth (#48328547) Attached to: First Experimental Demonstration of a Trapped Rainbow Using Silicon
The paper is entirely numerical simulation, despite what the linked blog post says. I quote: "In this paper, we numerically demonstrate an approach..". I'm not denigrating numerical simulations: I'm a computational physicist. Just, you know, RTFA?

Comment: Re:Not much worry with a source build (Score 2) 472

Did you build your own compiler? If not, how can you trust the binaries it produces? Have you dissected your CPU? How do you know it's executing the instructions you want and not quietly running other instructions too? As others have said, you have to draw the line somewhere. Personally, I have no trouble running a binary distribution (not sure why you pick on Ubuntu and not Redhat or Suse or Debian or FreeBSD, but meh)

Festo's Drone Dragonfly Takes To the Air 45

Posted by samzenpus
from the little-flyer dept.
yyzmcleod writes "Building on the work of last year's bionic creation, the Smart Bird, Festo announced that it will literally launch its latest creation, the BionicOpter, at Hannover Messe in April. With a wingspan of 63 cm and weighing in at 175 grams, the robotic dragonfly mimics all forms of flight as its natural counterpart, including hover, glide and maneuvering in all directions. This is made possible, the company says, by the BionicOpter's ability to move each of its four wings independently, as well as control their amplitude, frequency and angle of attack. Including its actuated head and body, the robot exhibits 13 degrees of freedom, which allows it to rapidly accelerate, decelerate, turn and fly backwards."

Comment: HTCondor (Score 1) 99

The HTCondor (formerly known as Condor) distributed computing project has always been free to use, but transitioned from a closed-source to open-source license a few years ago. Development of the software has been continuing unaffected, so far as I can tell. So: yes, it's definitely possible.

Comment: Re:Sputtering is experimental? (Score 2) 28

by henryteighth (#42764783) Attached to: Spintronics Used To Create 3D Microchip

Maybe by "experimental technique" they meant "a technique that is used in experiments",

Indeed. It is an "experimental technique" rather than a "theoretical technique" or a "computational technique", say. It's frustrating to read an abstract of a physics paper which sounds like the authors have performed a nifty measurement, only to find that in fact they are proposing an idea, or have performed a simulation, or theoretically analysed the problem. (Don't get me wrong, they're all equally important things, but not the same as performing an experiment). Thus, it's nice to emphasise one's "experimental technique".

Comment: Without hot air (Score 1) 626

by henryteighth (#42744717) Attached to: Will Renewable Energy Ever Meet All Our Energy Needs? Great book which performs a detailed analysis and discussion about energy usage (written by a Physics Prof who is also chief scientific advisor to the UK Government's Dept of Energy), freely available for download as a PDF (Off-topic: he's also the author of a brilliant textbook on Information Theory, also available as a free PDF)

Comment: Misleading title (Score 3, Informative) 74

by henryteighth (#42679177) Attached to: What Birds Know About Fractal Geometry
The title seems to be trying to suggest (to me at least, and based on the other comments here also to plenty of other readers) that birds can perceive fractal dimensions (FDs). However, if you read the journal article, it's all about a study of how the fractal dimension of the plumage correlates to different measures of the bird's health. They then also investigate some causative effects, by changing the bird's food intake and measuring the effect this has on FD. Nowhere in the article do they make any claim that birds can necessarily perceive or calculate a fractal dimension: the paper ends by saying "We therefore suggest that considering FD should shed new light onto the evolution and maintenance of complex animal patterns. " So they suggest (entirely reasonably IMHO) that it would be interesting to study that latter aspect, which is quite an important difference from what the Slashdot title is trying to imply.

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