I swear this takes you a really neat video. Honest.
This is a visualization of the network packets of a YouTube video, slowed down 12 times. You can clearly see the handshake, some odd client/server negotiation, and the full ramp-up.
…
The data is from a real tcpdump of the first 4 seconds of Rick Astley’s music video.
Learning Science in a video game
River City is a multi-user virtual environment, based in ActiveWorlds … Students make avatars, talk to citizens in the world (some are dumb AIs, but they can be puppetted by the teacher), and have a workspace in which they can perform water quality tests and other diagnostics, record the results, and create and test hypotheses. The software design includes the ability to record what steps students take, in what order, how often they repeat content lessons or experimental steps, and other aspects of their approach to solving the problem.
It’s not the first time a game has taught science skills, but this time it’s deliberate. I really like how you have the opportunity of creating a mysterious illness for the students to investigate, and this leaves open the possibility of it not being a real one. So instead of the the situation where someone could simply apply memorization to the problem and say, “Oh, the symptoms are X, Y and Z, but not A or B? It’s the plague. Fleas carried by the rats,” you have a number of perturbations which might not correspond to any real-life disease, and which means some actual problem-solving skills are in play. Which is tough(er) to do in physics.
A week ago it was geckos. Now, I can almost hear Samuel L. Jackson saying, “There are Mothef—— robots on this Mothef—— plane!”
New “Wind Lens” Turbine Magnifies Wind For Increased Power, Reduced Noise
There are a number of stories about this, and for most of them the technical explanation starts and ends with “The structure works similarly to a magnifying glass that intensifies light from the sun — except in this case, the lens intensifies wind flow” or something similar. Which is really frustrating. This story doesn’t, and even provides a link to the university web site, so perhaps we can glean additional information from that.
OK, it looks like this “lens” is a venturi of sorts. I’m neither a fluid mechanic nor an aeronautical engineer; I imagine the compressibility of the air makes this a little different for air than for water. But when you restrict the area of flow, the speed increases. Put another way, by funneling/focusing you increase the energy density of the air, so more energy is present within the area of the turbine and you can extract more energy without making the blades bigger. That much I get. I’m not sure if this accounts for all of the increased efficiency or if there are other effects as well, like improved efficiency by generally having higher speeds. It certainly doesn’t look like you are tripling the capture area from the pictures.
The stories tout this as being great, but I notice that the turbines are ~1 kW, as opposed to commercial turbines which are MW-ish beasts, and the researchers do not say how far this effect will scale up, and in fact caution that it will not. The bits about how these might be less objectionable on aesthetic grounds don’t sway me — there’s no justification that these will look pretty to those who disapprove of regular turbines. So I’m not seeing these as “farms” and >100 m diameters would seem to exclude them as being put up in your yard.
Secrets of the gecko foot help robot climb
A Stanford mechanical engineer is using the biology of a gecko’s sticky foot to create a robot that climbs. In the same way the small reptile can scale a wall of slick glass, the Stickybot can climb smooth surfaces with feet modeled on the intricate design of gecko toes.
If you watch the video, you might notice that they appear to have edited out a section discussing the need for a tail — the only kept the part when they added the tail and tell us the “now stickybot can climb.” It’s too bad, because I think there’s a bit of interesting physics there. It’s mentioned briefly in this video, where you can see a real gecko with its tail pressing against a surface, the hind legs acting as a fulcrum, so that it can move its upper body back toward the surface.
Mindset List for the Class of 2014
The class of 2014 has never found Korean-made cars unusual on the Interstate and five hundred cable channels, of which they will watch a handful, have always been the norm. Since “digital” has always been in the cultural DNA, they’ve never written in cursive and with cell phones to tell them the time, there is no need for a wrist watch. Dirty Harry (who’s that?) is to them a great Hollywood director. The America they have inherited is one of soaring American trade and budget deficits; Russia has presumably never aimed nukes at the United States and China has always posed an economic threat.
…
– John McEnroe has never played professional tennis.
– Clint Eastwood is better known as a sensitive director than as Dirty Harry.
– They never twisted the coiled handset wire aimlessly around their wrists while chatting on the phone.
– Woody Allen, whose heart has wanted what it wanted, has always been with Soon-Yi Previn.
… gettin’ old …
I want a doctor to take your picture
So I can look at you from inside as well
Coloured X-Rays of Flowers : Turning X-Ray Into An Art by Hugh Turvey
Why Does College Cost So Much?
They’re promoting an upcoming book, so the article is merely a summary, but from it arises an interesting premise: education is not an industry that benefits greatly, efficiency-wise, from technology. And that’s an interesting point. If there is a limit to how quickly a student can absorb knowledge, and I think there probably is, then any teaching efficiencies you might gain by adding technology are limited, and certainly won’t scale the way it does in other industries, where you might be able to automate processes and eliminate positions and have the potential to reduce costs.
Technology certainly helps the student; I shudder to think of what writing a thesis would have been like without a word processor program, having had the undergraduate experience of writing papers on an electric typewriter and concocting exams in the navy back when they were much more computer-phobic (cut-and-paste was a literal action, not a mouse-click). But that’s not going to get more information into their collective heads in a fifty-minute lecture, or make them read a book faster. It certainly doesn’t scale according to Moore’s Law.
Computers and peripherals (e.g. processing power, storage, networking) are deflationary. The price of all of the related hardware has been roughly constant over the years — and that doesn’t even reflect inflation: it still costs about a thousand dollars of today’s money to buy a middle-of-the-road computer, a few hundred bucks for a monitor, and another hundred for an external hard drive. But the increase in computing power, sizes of monitor screens and capacity of hard drives has been huge. That helps hold down costs in a lot of places, but if it can’t help the professor teach a class, it’s not going to hold the cost of instruction to the level of inflation. Not until you have robotic teachers, at least.