bodmas blog

• Wikipedia page on ruler and compass constructions in general and famously impossible constructions
• Graphical Ruler and Compass Editor Java applet allows you to place points on a canvas and then build constructions
• GCSE constructions including midpoint of a line and bisection of an angle
• Constructions for regular polygons and a table of possible constructions (heptagons are not constructable as 7 is a prime number but not a Fermat prime). This nice page includes two constructions for the 17 side regular polygon (heptakaidecagon) and one for a pentagon.
• Mathworld page on ruler and compass constructions with nice diagrams
• Crop circle patterns reduced to ruler and compass This page details a number of standard constructions and how to overlap them to make a ‘crop circle’. A lot of people think that crop circle patterns are too complex to be made overnight by Maths undergraduates with a plank, some rope, a few stout pegs, and a water bottle full of Jim Beam. Me?, I’m staying quiet….

• Dr Robert Moog has handed in his patch cord
• TL-78’s have a lot to answer for
• Remarkable dearth of circuits on the Web – most to do with radio communications (where most of the ideas came from)
• VCOs, VCAs and LFOs as well as envelope shapers I never did finish mine but the control panel looked wicked
• MS Excel Spreadsheet produces sound – by the invincible Erich Neuwirth – acts as fourier synthesiser but alas only for Windows based Excel implementations

Jason Smathers who stole 90 million AoL e-mail addresses and sold them in alphabetical blocks to spammers is sent to prison for a year and a bit. He also has to pay restitution to AoL at the usual inflated level that US courts seem to impose.

• Smathers was prosecuted under the US federal CAN-spam law as well as laws concerning interstate transportation of stolen property.
• There have, as yet, been no prosecutions under the UK anti-spam laws.
• Most spam originates in the US and the Americas generally, less than 2% originates from the UK
• According to the BBC News report , “AOL said Mr Smathers’ act had cost the company at least $300,000 (¬£166,240), although the judge said that figure was speculative. The judge ordered Mr Smathers to pay $84,000 (¬£46,560) in restitution, but he delayed the order so that AOL could prove whether the damages were higher.”
• Nice to see healthy skepticism from a judge regarding the cost estimates put forward by a company in a case like this
• The Register report by John Leyden has more links to the background of this case

Nicholas Negroponte is head of the MIT Media Lab and is a great enthusiast for online learning and getting people connected. His book ‘Being Digital’ while somewhat ‘gee wizz’, is a very strong argument for getting as much stuff and services online as possible.

The $100 laptop project (running Linux, wireless, 500 MHz processor and 1 Gb of storage using flash memory, cheap display adapted from portable DVD players) is aimed at giving as many children as possible access to personal computing.

“Bringing the laptop home engages the family. In one Cambodian village where we have been working, there is no electricity, thus the laptop is, among other things, the brightest light source in the home.” – Nicholas Negroponte

• The $100 laptop project page
• Connectivity using a peer to peer mesh with ‘cheap Internet backbone’ being thought about
• The hole in the wall – a contrasting approach developed in India
• Negroponte is talking about quantities of 100 millon. My question is what language is the keyboard going to accommodate?

There is already a Linux based wireless tablet available from Nokia , due for release third quarter 2005 (which means 2006, sometime, usually).

E-mails sent by naive people can be tracked to the server using information in the header, and laptops used on insecure WiFi access points can still be traced using the MAC address of the network card or wireless card.

Further correspondence illicited an anonymous apology from Johnny, who declined to reveal his identity. However, a hacker mate of Graham’s traced his email address to the Seattle medical centre, at which point Graham urged him to do the decent thing and turn himself in because, as Graham quite reasonably put it: ‘If you’re a nursing student in Seattle and you’re a clown, you’re pretty identifiable.’

From a report in The Register by Lester Haines about a clown stealing a bicycle

“the suspects wrongly believed that the use of an insecure wireless network in commission of the crime would mask their tracks. This failed when police identified the MAC address of the machine used to pull off the theft from a router and linked it to a GE Money laptop”

From a report in The Register by John Leyden about a Finnish computer security executive who decided to commit the perfect crime – and (as always) left a loophole.

• e-mail headers contain information about the route of the e-mail and the e-mail server at the organisation from which the e-mail was sent
• The Media Access Control – MAC - address identifies the network device being used to establish the network connection – the Wireless card in this case. The network card also has an MAC address hard wired into the chip. You can find the MAC addresses of your network and wireless cards easily. However the MAC address can be ‘spoofed’ – see the Wikipedia article above.

Q: How did you come to compose ``The Microsoft Sound’‘?

A: The idea came up at the time when I was completely bereft of ideas. I’d been working on my own music for a while and was quite lost, actually. And I really appreciated someone coming along and saying, ``Here’s a specific problem—solve it.’’

The thing from the agency said, ``We want a piece of music that is inspiring, universal, blah- blah, da-da-da, optimistic, futuristic, sentimental, emotional,’’ this whole list of adjectives, and then at the bottom it said ``and it must be 3 1/4 seconds long.’’

I thought this was so funny and an amazing thought to actually try to make a little piece of music. It’s like making a tiny little jewel.

In fact, I made 84 pieces. I got completely into this world of tiny, tiny little pieces of music. I was so sensitive to microseconds at the end of this that it really broke a logjam in my own work. Then when I’d finished that and I went back to working with pieces that were like three minutes long, it seemed like oceans of time.

From Q and A with Brian Eno June 2nd 1996