london terrorist attack news coverage

well, i'm safe, and importantly, so are all of my friends,,,

however, when watching the rolling news-24 coverage and viewing web news sites, i noticed some things about the disaster reporting that were different to earlier news reports. one thing i discovered was the wikinews collaborative news site. the most interesting was the footage and pictures from the evacuation of an LUL train - they were shot and taken on a camera phone. now, these are images that have never been broadcast before. the tube has been evacuated several times, and people got escorted through the tunnels to safety each time. before now, there was nobody with a camcorder around to document it... now that almost everyone has a camera phone, and video recording mobiles are getting more common, somebody was able to take these pictures

there must be hundreds of other newsworthy events taking place that we only have eyewitness spoken accounts of, which are notoriously unreliable and inaccurate, and these could now be backed up with pictures. also consider official statements and news agency reports about sudden events on the other side of the world - these could be verified by people at the locations being discussed by taking pictures, rather than the usual phone interviedw with a still image of a reporter. viewer's confidence in the truthfulness of the news media would be greatly increased if they knew it was being backed up by evidence from non journalists.

i was able to follow the reporting not only on the BBC site, but also using the flickr photo gallery services. people have been tagging their pictures as londonbombblast or london and bomb so i was able to add an RSS feed of these tagged images to my news aggregator, alongside the official BBC feed. the feed even presents the images in chronological order by timestamp, not in order of upload, to preserve an ordered view of events.
what this means is a lot more news imagery and footage will be available, of things as they happen from an eyewitness perspective, since tools like flickr allow uploading immediately from your mobile. so we will no longer have to wait hours for the camera crews to arrive to verify the official version of events, or be restricted to the one amateur video made by a tourist who happened to be in the right place at the right time. it will also become difficult or impossible to supress or modify images of events since before the police can rip the non-existant film out of the non-existant camera, you have uploaded the picture over the air. i think we are entering an exciting time for news and media, and will see a lot of things that just eye-witnesses experienced before. now, along with the interviews, we will see a slideshow of camera-phone pictures and films as illustration.

the big problem is, of course, managing this information. not as in censorship, but image overload. a flickr RSS feed is fine now, but this will become unmanageable. i think better tagging will allow filtering to be intelligently applied, and when GPS becomes more prevelant, pictures can be sorted by location too, with the attendant possibilities that provides. we will need to have news articles annotated with relevant meta-data to allow automatic linking to picture search engines, and even normal searching. this is just part of the whole 'semantic web' movement, really, where every document is tagged with some meta-data giving it a real-world meaning and context. the semantic tagging allows other programs to provide the links between different content streams in a useful way.

i'm going to the open tech 2005 event on 23 july, so maybe they will have some interesting ideas since BBC backstage (content feed providers) is sponsoring it...

(the other obvious issue is verification of the identity and hence trustworthiness of the photo-taker. this is another problem entirely, however...)

guardian sudoku-ness

i noticed today that the guardian now has its very own sudoku puzzle. since this is puzzle number 24 from saturday, i can surmise that they've had this for less than a month and i've simply not noticed.

the one thing that impresses me is, however, the starting grid for the puzzle. it consists of two squares rotated 45 degrees right in which the numbers 1-9 are placed in order, top to bottom then left to right. one square is at top right, one at bottom left. preserving rotational symmetry (180 degrees about the diagonal) while removing reflectional, two numbers are also placed in the top-left and bottom right squares.

which brings me to another question - is the starting setup of a sudoku puzzle copyright? i guess it probably is, and apologies to the guardioan for the following (although it is fair use, as a quote for review purposes or a citation for educational purposes perhaps?) i also assume that the finishing grid might be copyrighted/able, since it is concievable someone could solve your puzzle then produce another starting position that is derived from your finhing grid... or should i just be pleased with the guardian's hard work on the design of (at the very least) puzzle number twenty four, medium:

...|...|1..                           1  
.5.|..2|.4.                      5   2 4 
6..|.3.|5.7                     6   3 5 7
---+---+---                          6 8 
...|..6|.8.                       1   9  
..1|...|9..                      2 4     
.2.|4..|...                     3 5 7   6
---+---+---                      6 8   2 
3.5|.7.|..6                       9      
.6.|8..|.2.
..9|...|...

now, i've been trundling around the web and found some interesting sudoku related things... firstly, this is an automated web sudoku solver which also gives a list of the steps it took to find the solution. there's a blog which gives the solutions to various newspaper puzzles as well. regarding my query about the total number of sudoku grids possible, this blog thread seems to have come up with an answer - the maths is as hard as i thought it would be, and i'm sure it would have taken me a lot longet to work it out - i was still nowhere near. the number is apparently 6,670,903,752,021,072,936,960 which is equivalent to 9! x 72^2 x 2^7 x 27,704,267,971. see also the wikipedia entry for sudoku for a lot of interesting information...

phone scam hoaxes

i recieved the following email at work today:

Phone Fraud - Warning
We have been advised of a telephone fraud currently in operation - this applies to home and work telephones, landlines and mobiles.

If you receive one of these fraudulent calls, upon answering the telephone you will hear a recorded message congratulating you on winning an all expenses trip to an exotic location. You will then be asked to press 9 to hear further details. If you press 9 you will be connected to a premium rate line that costs approximately ?20 per minute. Even if you disconnect immediately, it will remain connected for a minimum of 5 minutes costing around ?100. The final part of the call involves you being asked to key in your postcode and house number, which has other serious consequences. After a further 2 minutes you will receive a message informing you that you are not one of the lucky winners. The total bill by then will be ?100 (though Trading Standards have confirmed to me that there's some question about the actual costs, but they're still extortionate) .

Since the calls are originating from outside the UK, BT and other telephone companies are left relatively powerless to act. The only safe solution is to HANG UP before the message prompts you to dial 9, even safer HANG UP on any unsolicited 'free offer calls'.

There is another scam operating on mobile phones as well. A missed call comes up. The number is 0709 020 3840, the last four numbers may vary, but certainly the first four will remain the same. If you call this number back you will be charged ?50 per minute. People have complained about their phone bills, once they have realised the cost of the call, but apparently this is completely legal. So beware, do not call back numbers beginning with '0709'.

needless to say, it's all a hoax or urban myth. basically, there are no phone lines that cost more that GBP 1.50 per minute. any that do cost this much will start '09' - these numbers are regulated by ICSTIS. anyway, when called by someone, pressing digits on your phone will never cause any amount to be added to your bill - this is just impossible. as long as someone else calls you, they will be paying for the call. the number '9' has no special functions when pressed during a call.

any phone number beginning with '0709' is a 'find me anywhere' personal number, as defined by OFCOM, and they have been allocated to various companies. admittedly, the pricing structure for these numbers can be somewhat confusing, ranging from local rate to mobile-equivalent rate, and including fixed price per call. however the BT pricelist lists the rate bands. these will be charged by BT at no more than 50p per minute.

a summary of the charges, in pence per minute is shown below:

0709 01         k       37.5p
0709 02         pn2     50.0p
0709 03         pn3     49.0p
0709 04         pn4     26.0p
0709 05         pn6     20.0p
0709 06         j       32.0p
0709 07         pn2     50.0p
0709 08         k       37.5p
0709 09         k       37.5p
07091           k       37.5p
0709 20         k       37.5p
0709 21         k       37.5p
0709 22         k       37.5p
0709 23         k       37.5p
0709 24         k       37.5p
0709 25         k       37.5p
0709 26         k       37.5p
0709 27         k       37.5p
0709 28         k       37.5p
0709 29         k       37.5p
0709 40         pn2     50.0p
0709 41         pn4     26.0p
0709 42         k       37.5p
0709 43         k       37.5p
0709 44         pn9     23.5p
0709 45         j       32.0p
0709 46         pn2     50.0p
0709 47         k       37.5p
0709 48         e        5.0p
0709 49         k       37.5p
0709 65         pn2     50.0p
0709 66         pn2     50.0p
0709 67         pn2     50.0p
0709 68         pn7      4.0p (plus 50.0p fixed cost)
0709 69         pn5     17.0p
07099 0         d       16.7p
07099 2         f       30.0p
07099 4         pn2     50.0p
07099 5         k       37.5p
07099 6         k       37.5p
07099 8         pn2     50.0p

ajax applications

i've been looking at 'ajax' web applications, which are basically things like google maps, google gmail, amazon a9 and other interactive pages that don't rely on server round-tripping to deliver a response to the user. ajax applications provide most of the front-end interaction in a javascript layer running on the browser, which fetches XML and XHTML behind the scenes and uses the DOM to display and manipulate the data. the word 'ajax' is actually an acronym, meaning 'asynchronous javascript and XML' (or '... and XMLHTTPRequest' or '... and XHTML/CSS' according to some people) and is best explained by this essay by adaptive path. also woth a look on the technical side is this blog on XMLHTTPRequest development.

anyway, the company 37 signals produce several pretty useful ajax applications. i particularly like tadalists for web browseable todo lists, and 'backpack' for managing notes and other information, although this costs real money for the most useful features...

here is a list of good ajax resources:

• ajax design patterns wiki
  
• aricles and tutorials about ajax
  
• ajaxian, an ajax blog
  
• openajax, another ajax blog
  

su-doku questions...?

spurred on by occular's post, i decided to try and write my own deterministic sudoku solver. at the moment i'm using java, but i think that prolog or any other AI language would be ideal. anyway, i had a few thoughts while doing this, which i don't know the answers to (yet...)

• how many finished 9x9 sudoku grids are there?
  
• how do you create the starting grids - is it simply backtracking from a finished square that fulfills the constraints?
  
• in connection with the previous, it should be noted that most starting grids i've seen have 180 degree rotational symmetry about a diagonal, sometimes 90 degree about both or reflectional about both, just like crossword grids
  
• is there a way to determine the 'difficulty' of a particular starting grid deterministically, or is it purely subjective?
  

if anyone has any ideas, i'd be interested...