AOPD has a picture of the Sept 26th aurora (see my post here) taken further north in Tromsø, Norway, which shows what you can get given better lighing conditions and location. The image contains no EXIF so no idea on the exposure time but I guess it is similar to mine.
Friday, 30 September 2011
Thursday, 29 September 2011
Alloy...
Very surprised to see a posting about Alloy - a small, lightweight (in process terms) and easy to use formal specification language - on the Good Math, Bad Math blog....and in true internet style, here's a link to that posting:
I wrote a couple of papers on our use of Alloy and as there's a link to this blog, I'll at least list the one that details our experiences:
A Taste of Specification with Alloy
In my last post (which was, alas, a stupidly long time ago!), I talked a bit about software specification, and promised to talk about my favorite dedicated specification tool, Alloy. Alloy is a very cool system, designed at MIT by Daniel Jackson and his students.
Alloy is a language for specification, along with an environment which allows you to test your specifications. In a lot of ways, it looks like a programming language - but it's not. You can't write programs in Alloy. What you can do is write concise, clear, and specific descriptions of how something else works.
I'm not going to try to really teach you Alloy. All that I'm going to do is give you a quick walk-though, to try to show you why it's worth the trouble of learning. If you want to learn it, the Alloy group's website has a really good the official Alloy tutorial. which you should walk through.
I wrote a couple of papers on our use of Alloy and as there's a link to this blog, I'll at least list the one that details our experiences:
- Ian Oliver (2007). Experiences of Formal Methods in 'Conventional' Software and Systems Design. BCS FACS Christmas Workshop: Formal Methods in Industry, BCS London, UK, 17 December 2007.
Wednesday, 28 September 2011
Integration "In The Large"
Position paper accepted at the W3C Workshop on Data and Services Integration, October 20-21 2011, Bedford, MA, USA
Integration "In The Large"
Ian Oliver, Ora Lassila
Nokia
September 2011
The original goals of the Semantic Web - and in some degree also those of its younger cousin" Linked Data - are to provide novel solutions for the integration and interoperability of systems, and to move towards a situation where more information work can be automated. These solutions are well understood in the small", as we can relatively easily define and expose the semantics of any system of limited scope, but larger-scale integration still eludes us. This is due to the fact that ultimately reconciling the semantic differences of many individual systems at the level of data is destined to suffer from issues of achieving consistent global agreements (and as such we are dealing not only with technical issues, but also and perhaps more importantly with social and organizational challenges).
Aurora Borealis
Quite a nice show last night (27 Sept) with aurora and a couple of meteors for good measure (note, the white line in the sky is an aircraft inbound to Helsinki-Vantaa airport.
This one has been enhanced a little (additional contrast, darkening the shadows) - exposure was 30s and ISO800, f/4 with Sigma 10-20mm lens (focal length was 10mm).
And an "unadulterated" which includes Ursa Major (just below center of the picture) - ISO1600, f/4, 31sec with Sigma 10-20mm at 10mm.
An here's and article about the sunspot and flare that generated all this: http://www.nasa.gov/mission_pages/sunearth/news/News092511-ar1302.html
This one has been enhanced a little (additional contrast, darkening the shadows) - exposure was 30s and ISO800, f/4 with Sigma 10-20mm lens (focal length was 10mm).
And an "unadulterated" which includes Ursa Major (just below center of the picture) - ISO1600, f/4, 31sec with Sigma 10-20mm at 10mm.
An here's and article about the sunspot and flare that generated all this: http://www.nasa.gov/mission_pages/sunearth/news/News092511-ar1302.html
Monday, 19 September 2011
Ba? Fa!
Two posts on Bad Astronomy today (one of Neptune) and this....
Must admit, Bad Astronomy is a seriously fantastic blog...
Ba? Fa!
Via MadArtLab comes this amazing optical/aural illusion that you have to see and hear to believe!
Cool, isn’t it? I’ve heard (haha) of this illusion before — it’s called the McGurk effect — but it’s still fun to see it done this way. When the man is shown side-by-side saying it, switch your attention back and forth between them with each syllable. Even knowing it’s an illusion, it’s still overwhelming. I can’t not hear it.
Must admit, Bad Astronomy is a seriously fantastic blog...
Neptune (in infrared)
Skymania has an article on Neptune taken with the Keck 10m telescope in infrared. Given the distance to Neptune the quality of the pictures is incredible especially if compared with the Voyager 2 pictures from 1989.
This also appeared on the Bad Astronomy blog: Neptune is *really* far away...which also explains something about the distance to Neptune and the difficulties of taking pictures...
Stunning snaps of Neptune and Triton
Posted by Paul Sutherland on September 18th, 2011
Here are a couple of views of Neptune as you have probably never seen the planet before. They were captured earlier today by astronomer Mike Brown using a 10-meter (33 ft) telescope at the W. M. Keck observatory on Hawaii.
This also appeared on the Bad Astronomy blog: Neptune is *really* far away...which also explains something about the distance to Neptune and the difficulties of taking pictures...
Sunday, 18 September 2011
Probably the best office in the Universe...
Currently, I guess this is the best office in the known Universe....
Thursday, 15 September 2011
A Russian Experiment
My Family’s Experiment in Extreme Schooling
By CLIFFORD J. LEVY , Published: September 15, 2011
Fascinating article in the New York Times about one family's move to Moscow and their experiences in a Russian private school. Apart from the discussions about the linguistic challenges (3 non Russian speaking American children) and the cultural differences, the teaching style employed is extremely interesting as exemplified here:
New Humanitarian had standard subjects, like history and math, and Danya had many hours of homework a week. But Bogin added courses like antimanipulation, which was intended to give children tools to decipher commercial or political messages. He taught a required class called myshleniye, which means “thinking,” as in critical thinking. It was based in part on the work of a dissident Soviet educational philosopher named Georgy Shchedrovitsky, who argued that there were three ways of thinking: abstract, verbal and representational. To comprehend the meaning of something, you had to use all three.
When I asked Bogin to explain Shchedrovitsky, he asked a question. “Does 2 + 2 = 4? No! Because two cats plus two sausages is what? Two cats. Two drops of water plus two drops of water? One drop of water.”
From there, the theories became more complex. In practice, though, the philosophy meant that Bogin delighted in barraging children with word problems and puzzles to force them to think broadly. It was the opposite of the rote memorization of the Soviet system.
At dinnertime, the kids taunted me with riddles. “Ten crows are sitting on a fence,” Arden announced. “A cat pounces and eats one crow. How many are left?” “Umm, nine,” I said, fearing a trap. “No, none!” she gleefully responded. “Do you really think that after one crow is eaten, the others are going to stick around?”
Philosophy and classes on "thinking" should be mandatory everywhere!
Tuesday, 6 September 2011
Apollo Landings
Amazing pictures from NASA's LRO Moon orbiter of some of the Apollo landing sites - complete with footsteps, remains of the moon lander and moon buggies....
and as always, The Register have a report too...
Media briefing materials associated with this story can be found here.For example, Apollo 12's landing site complete with their visit to the Surveyor 3 lander:
NASA's Lunar Reconnaissance Orbiter (LRO) captured the sharpest images ever taken from space of the Apollo 12, 14 and 17 landing sites. Images show the twists and turns of the paths made when the astronauts explored the lunar surface.
and as always, The Register have a report too...
Eyes on the Solar System
This is seriously cool!
http://solarsystem.nasa.gov/eyes/
"Eyes on the Solar System" is a 3-D environment full of real NASA mission data. Explore the cosmos from your computer. Hop on an asteroid. Fly with NASA's Voyager 2 spacecraft. See the entire solar system moving in real time. It's up to you. You control space and time.
http://solarsystem.nasa.gov/eyes/
"Eyes on the Solar System" is a 3-D environment full of real NASA mission data. Explore the cosmos from your computer. Hop on an asteroid. Fly with NASA's Voyager 2 spacecraft. See the entire solar system moving in real time. It's up to you. You control space and time.
Saturday, 3 September 2011
Severn Tunnel, 125 years
Severn Tunnel linking Wales to England is 125 years old
3 September 2011 Last updated at 08:35 GMTCarwin Jones
The Severn Tunnel rail link which joins south Wales and England, is 125 years old.
About 200 trains pass through this feat of Victorian engineering every day, but given its age, is it still fit for 21st Century use?
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