Wikipedia:Reference desk/Archives/Computing/2008 March 23

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[edit] March 23

[edit] QWERTY, Dvorak, Chorded...

What kind of keyboards do world record typists use ( I think I read dvorak ) and how do chorded keyboards compare in speed? What speed can the top 5% fastest typists hope to achieve in each of the three?

Secondly, is there an international dvorak keyboard, for e.g. french accents or a german version thank you!!!!—Preceding unsigned comment added by 79.122.61.150 (talk • contribs)

Further information: Keyboard (computing)
This study, which I presume only tested QWERTY typing, rates the top 5% as capable of 70wpm. I found this using Google Scholar; perhaps further down they includes a study directly comparing QWERTY with another keyboard.
"Barbara Blackburn, the world's fastest typist" (as linked from the Dvorak article) is a Dvorak user; that link (to what appears to be a Dvorak advocacy site) sources the 1985 Guinness Book of World Records, so later keyboard schemes (like the Colemak) weren't in the running when that record was set.
The Dvorak article also mentions non-english configurations, including French and German. It also says these keyboards leave the Roman characters in the same position as the English, which may be not optimized for other languages. (A note from a Norwegian user complains that version has issues.) No standard "international" version is mentioned.
Colemak's pool of users is very small, perhaps only a couple thousand, but speeds are said to be similar to Dvorak or QWERTY. A thread on Colemak forum laments the lack of studies.
According to the article Words per minute, Stephen Hawking peaked at 15wpm. I have tested at 65wpm; however, it took me several seconds to type QWERTY each time above, and again just now. Weird.
The variety of schemes for chorded keyboards, and their uncommonness, makes it hard to find comparative speed studies. Steno typists routinely exceed 200wpm, albeit in an abbreviated, not generally intelligible style that omits much detail. Chorded keyboards (especially if one-handed) are usually much slower because requiring multiple fingers for each character makes it difficult to type short strings of characters in quick combination, a common muscle memory optimization learned in regular (non-chordal) typing; however, many chording schemes support programmable macros for frequently-typed words, which speeds things up a bit. (Macros are also possible on non-chording keyboards.) Few comparative studies seem to exist for chording keyboards; "wearable" computer guru Thad Starner publishes some anecdotal-looking figures here. I have not heard of chording keyboards designed to be faster than QWERTY or Dvorak typing. / edg 01:25, 23 March 2008 (UTC)

thank you!!! Very useful answers :) I wonder how much of stenographers' speed isn't JUST the abbreviations. For example, have any of them who are typists too just tried typing on QWERTY using their abbreviated style?

I made a few changes to the above before I realized it had been replied to. My guess on steno methods in touch typing: theoretically there should be an improvement, but I wouldn't count on steno skills being routinely leveraged to enhance touch typing speed. Typing fluently relies heavily on muscle memory, and I doubt steno methods translate automatically to touch; the mind knows the abbreviations, but the tendons are ignorant.
It was fun reading up on this stuff. Now I want to learn Colemak. / edg 05:22, 23 March 2008 (UTC)
I tried until it gave me a headache o_o :D\=< (talk) 21:00, 23 March 2008 (UTC)
I believe Dvorak keyboard was developed just to overcome the hammer jamming problem on mechanical typewriters. Since mechanical typewriters are not used any more, Dworak keyboard is no better than QWERTY keyboard. And Dworak keyboard was improvement only with some languages. With some other languages, it might have been worse. -- PauliKL (talk) 01:15, 24 March 2008 (UTC)
No, the opposite is true. QWERTY was developed because of typwriters jamming. Dvorak then came about because of the inefficiency of the QWERTY keyboard. --Voyaging (talk) 01:19, 24 March 2008 (UTC)
Yeah, I used to be a semi-nerd on this stuff back when "word processor" meant IBM Selectric and 1) all the serious contenders for typing speed used Dvorak because 2) Dvorak is designed so as much as possible can be typed without ever moving your fingers from the home keys. (added two seconds later: would this mean that Dvorak would not be optimal for other languages then, with different letter frequencies?) Gzuckier (talk) 19:12, 24 March 2008 (UTC)

[edit] Search Providers

Hello. What is the difference between the Wikipedia (English) and Wikipedia (en) search providers in Internet Explorer 7? Thanks in advance. --Mayfare (talk) 00:36, 23 March 2008 (UTC)

They are probably just made by different people. Mac Davis (talk) 00:50, 23 March 2008 (UTC)

[edit] Any free audio output pitch shifter?

I'm looking for a free audio output pitch shifter for Windows or Mac OS X which can shift the pitch of the output audio just like the one used by Realtek. Funny Voice doesn't work so well because if I select Stereo Mix, the speaker output becomes the input and a feedback occurs. The other software that turned up are shareware. Do you know any free program that can do the above? --KLLvr283 (talk) 06:32, 23 March 2008 (UTC)

[edit] digital kicks

When producing tracks with a lot of digital sythesizers, and trying for a strong bass kick, I often notice a quiet high-pitched whine that accompanies the low-frequency waves, and I've begun noticing the whine present in proper commercial tracks as well (here is an old track from the orb and you can hear the high-pitched whine really clearly). It seems to be most noticeable on warmer, deeper, more pure sounding kicks, as opposed to rough or fat ones. What is this whine? Do all synthesizers produce this wine? Can it be avoided?? And why is it so prominent even in commercial music... do people not really not notice it? Thanks.  freshofftheufoΓΛĿЌ  08:48, 23 March 2008 (UTC)

I didn't really notice it (on the computer speakers..)
First of all you say it accompinanies the base - you mean the beat (thud,thud) all the way through or some particular low frequency bit eg 1.58s in etc
Secondly yes - I'm familiar with this song and seem to remember that when player on a better system it contained a lot of whine - almost like interference noise like when you de tune very slightly a FM radio in addition to all the birdy clicks and whistles.
Q. Is it possible that the noise (whine) is simply electronic noise , and unintentional, - note it would only be audible on low frequency notes because it would be drowned out when synthesising high frequency notes?87.102.16.238 (talk) 10:55, 23 March 2008 (UTC)
You might not be able to tell with little computer speakers that don't pick up quiet frequencies, but I can hear it alright on my laptop. I know what I'm looking for though, and that might be a factor. It accompanies the "thudding" yes, the kick. It doesn't seem to be anything to do with the deepness of the note, rather the amount of punch of the note, hence it doesn't come up anywhere else. It very well could be some kind of "electronic noise", and that's what I assume it is. It's nothing to do with the song really; as long as you can hear the kick clearly (this gave me an idea: NIN - closer has a really clear kick, and I can hear the whiney thing even clearer on that track). I'm starting to wonder if it's some kind of feedback from the speaker coils; I don't have any large speakers to test it on, but I get the same effect when listening on my laptop, with my cheap earbuds, and with my sony monitor headphones that I use for recording. It would make sense because the thud of the kick might cause some excess vibration in the speakers, but what doesn't make sense is that it doesn't seem to matter what volume level you use, and I can actually hear the whine more on my cheap buds, although it's just as obvious with my high quality headphones. One last note is that I can still hear the sound when creating kicks with high quality instruments like Sylenth, so I don't think it has anything to do with audio encoding. Hmm...  freshofftheufoΓΛĿЌ  11:17, 23 March 2008 (UTC)
ok I don't think I can hear it on that - second thud is more buzzy eg (thud, bzthud, repeat) - Maybe I'm too old to hear it (is it very high pitched). I recognise the sort of thing you're talking about - but can't hear it right now.)87.102.16.238 (talk) 11:28, 23 March 2008 (UTC)
Maybe you can find a similar sound here http://www.synthmania.com/Famous%20Sounds.htm 87.102.16.238 (talk) 11:24, 23 March 2008 (UTC)
Well the closest would obviously be the 808 drum kick, but the sample on that site doesn't produce the whine for some reason; I don't think it's quite as sharp enough. Funny thing is, on Youtube again there's a video of a guy with his TR-808 and it's really noticeable on the kicks (link) but now it's starting to sound like it's the compression on Youtube that is causing it, but that wouldn't explain why I can get it on my computer from the instruments directly. It's pretty high, and I thought to myself if it would become invisible with age but I don't think it's quite that high (it's kind of hard to tell), and I'm 25 anyways so there shouldn't be that much of a difference. No big deal I guess, just when I'm trying to get really low sine-wave style bass lines (think of old jungle/dnb) it can take up nearly as much audible space as the bass itself and it bugs me. I'll have to try it out on some full-size speakers to see if it doesn't just disappear.  freshofftheufoΓΛĿЌ  12:28, 23 March 2008 (UTC)
My hearing may have gone, all I can hear is a 'breathy' sound following the 'hits'. Wait for someone a bit younger and less deaf to answer..87.102.16.238 (talk) 14:21, 23 March 2008 (UTC)
i cant check on this yet until I get home, but is it possible it's just your PC? Something to do with the D to A hardware? Gzuckier (talk) 19:10, 24 March 2008 (UTC)
You know what... I knew I had a crappy sound card but for some reason I never thought that it might be the cause of the weird sounds. I've just installed new drivers (Realtek, btw), and the whining is gone! It was so easy... thanks a lot! Sorry for making everyone strain their ears and stuff : (!!!  freshofftheufoΓΛĿЌ  06:10, 26 March 2008 (UTC)
Glad it's gone. It's possible you disabled/reset a DSP when you reinstalled the drivers. I would've suggested another place to check is any sound enhancement features you may have activated — things like software-based equalizers, "3D sound"/"SRS" buttons, or even Windows' own poorly-documented "speaker setup" (Sounds/Multimedia control panel -> Audio -> Sound Playback -> Advanced, which I leave set on 'headphones'). The software EQ for my external soundcard does not do proper filtering and introduces harmonic distortion that sounds like the higher-pitch whines you describe, most noticeably on percussive bass sounds. —mjb (talk) 17:17, 28 March 2008 (UTC)

[edit] C programming

I'm doing a problem in C http://projecteuler.net/index.php?section=problems&id=56 Do I have a problem with this line:

seperate_and_add_digits( Digit[][100],100,100);

I'm getting a syntax error:']'

seperate_and_add_digits is a function with prototype:

seperate_and_add_digits(long double digits[][100],int rows,int columns);

What do you think you're doing with that syntax? You can never have an empty pair of brackets in regular statement like that. In the prototype, they're declaring a pointer. (C function parameters are never actually arrays. The digits parameter is a pointer to an array of 100 long doubles.) Making up syntax that doesn't exist is a sign that you've probably got major conceptual problems that can't be solved by looking at a couple of lines in isolation. --tcsetattr (talk / contribs) 09:35, 23 March 2008 (UTC)

I wanted to initiate a function that takes a two dimensional array, rows and columns as parameters88.203.106.28 (talk) 10:04, 23 March 2008 (UTC)


You can't initialize a variable while calling a function - put the two on separate lines:

long double Digit[][100];
seperate_and_add_digits(Digit, 100, 100);

It's generally a good idea to use a #define to declare the size of an array - this makes it much, much easier if you want to change the size of the array. I generally avoid data[] too, preferring to explicitly say the size of the array (eg data[100]):

#DEFINE SIZE_WHATEVER 100
void foo( long double data[SIZE_WHATEVER][SIZE_WHATEVER] ) { /* ... */ }
void main() {
   long double data[SIZE_WHATEVER][SIZE_WHATEVER];
   foo( data );
}

--h2g2bob (talk) 13:49, 23 March 2008 (UTC)

[edit] WHOIS

I know I can use WHOIS to find out the registrant of a domain name, but is there a way of then finding out all other domain names registered by that individual? --Richardrj talk email 10:37, 23 March 2008 (UTC)

It sounds like Reverse telephone directory. I don't know if it is possible. I hope someone comes to answer this question. Kushal 01:16, 25 March 2008 (UTC)

[edit] news site

Hi. Can someone recommend a great site for the latest computer tech news. I don't want somewhere that mostly covers the latest intel/amd cpus and ati/nvidia graphics cards - more something that covers all 'computer tech' - processors (of all types), manufacturing processes and research, maybe other science related stuff. No 'linux'/'windows'/'apple' biased sites please. Not slashdot.. something sensible.

Any ideas?87.102.16.238 (talk) 12:38, 23 March 2008 (UTC)

slashdot :D:D or Ars Technica :D\=< (talk) 13:22, 23 March 2008 (UTC)
Most news sites have a tech section: Guardian Times BBC. --h2g2bob (talk) 13:25, 23 March 2008 (UTC)

I Don't rely on BBC/Guardian/Times etc - find they get stuff just wrong too often.

Arstechnica is ok, I suppose, anything like that - but better, more complicated, and more exciting?87.102.16.238 (talk) 14:02, 23 March 2008 (UTC)

Ars is the professional journalism face of tech news. If you're willing to sacrifice professionalism and accuracy for something that moves faster, just read slashdot.. :D\=< (talk) 16:32, 23 March 2008 (UTC)
The discussion is part of the appeal of Slashdot too; 100 comments for a story is on the lower end, though it's just about unheard of for other news sites. How much of the appeal it is depends on how much you enjoy trolling, wild guesses and speculation from people who don't read the article, and half the comments being about how Slashdot and its users/editors/moderation system are broken. :D -- Consumed Crustacean (talk) 19:57, 23 March 2008 (UTC)
We should have a moderation system here. If only those slashdotters could stay vaguely on topic, and too many shills there as well...

What about process and microarchitectural improvements, lithography, and more general electronic news (eg high frequency amplifiers etc) as well ... etc ... I find 'ars' to be quite PC centric - something a bit more 'physickey' any one know a good one.87.102.16.238 (talk) 16:50, 23 March 2008 (UTC)

Wired (magazine) had an article called Mother Earth Motherboard, which was very good. Kushal 03:45, 24 March 2008 (UTC)

I'm in the wrong country for that - though I'll read it if it's online? (link?)87.102.16.238 (talk) 11:12, 24 March 2008 (UTC) Scrub that - found it - please no more jetsetting cyber tourists please.87.102.16.238 (talk) 12:00, 24 March 2008 (UTC)

Yes! it is available online. I read it online. The full 56 pages of information and excitement is in this printable html copy here.

Another venue would be New York Times at [1] Cheers,

Kushal 12:59, 24 March 2008 (UTC)

[edit] Storing large numbers in VB 2005

Resolved.

Hello! I'm doing problem 16 from Project Euler, and I wanted to know if it was possible to store the precise value of 21000 in any of Visual Basic 2005 data types. I wrote a program for that question that divides 21000 (stored as double) by 10302 (because there seem to be 302 digits in that number) truncates the integer value, and then subtracts the result*10302 from 21000. I made it a loop so that the power of 10 decreases each time the loop is run. Anyway, I keep getting the wrong result for the sum of the digits of 21000 (to be exact, 1353). I read on the internet that double does not store the precise value, and I realized that was the reason I keep getting the wrong answer. Any suggestions on this?  ARTYOM  12:56, 23 March 2008 (UTC)

2^1000 is going to need 1000bits to store it to integer accuracy, a double is probably only 64 bits...
Two options here - write your own arithmatic programs (use strings or something to store the data)
Or - get a language that supports any length integer (or very long integers) - python can do this, most likely many others, Someone else can advise you better on this subject.87.102.16.238 (talk) 14:06, 23 March 2008 (UTC)
Visual Basic doesn't seem to have what you want see http://msdn2.microsoft.com/en-us/library/47zceaw7(VS.80).aspx maybe you can make a user defined data type or use string as a binary representation.87.102.16.238 (talk) 14:10, 23 March 2008 (UTC)
Ask if you want advise on how to use a string to store a binary number.87.102.16.238 (talk) 14:12, 23 March 2008 (UTC)
Okay, that would be helpful. Please explain if you have time!  ARTYOM  15:48, 23 March 2008 (UTC)
I once wrote VB4 functions to do calculations on arbitrarily long numbers represented as strings. They were written a bit naively but they get the job done. They should work on VB8 as well, and I can copy the code if you want.
Alternatively, if all you want is this particular problem, you can implement it rather easily. It's simple to add two integers represented as strings. So you can start with 1 and add the number to itself 1000 times. Then you just go over the string and add the digits. The result should be 1366. -- Meni Rosenfeld (talk) 14:35, 23 March 2008 (UTC)
Well, I tried to store the number as a string, but VB converts it to string in scientific notation. So far I couldn't make the string display the number itself rather than the *helpless* 1.07150860718626E+301. The answer you gave is correct, though, I would appreciate it if you could explain how you figured it :)  ARTYOM  15:48, 23 March 2008 (UTC)
Well if you're just going to use a string, then you can just do the math out long, the same way you would on paper. That way you'd have many intermediate results and it won't give you scientific notation. It's probably the slowest possible solution, and it might take a few seconds to calculate 2^1000, but it will work and it's easy to program.  freshofftheufoΓΛĿЌ  16:10, 23 March 2008 (UTC)
[ec] I used Mathematica. We didn't mean that you let VB calculate the power in floating point and then convert it to a string, but rather that you do the entire calculation from the ground up using strings. -- Meni Rosenfeld (talk) 16:12, 23 March 2008 (UTC)
HINT first you would need to write a function that adds two strings eg function_addstring(a$,b$) result=c$ (or whatever the equivalent VB syntax) is
So if a$="123" and b$="901" you will be adding 1+3, 2+0, and 9+1
Don't forget to included any carries eg 9+1=0 carry 1
It might help if you use fixed length strings (for simplicity) eg 2^1000 ~ 1000^100 ~ 10^300 so more than 300 digits should do. Therefor use "0000" + about 300 zeros +"002" for two.
Once you've got an 'add function' you can construct a multiply function from the add functions.
eg "1234" x "78" = 0 + "1234" (eight times) + "12340" (seven times)
Remember that multiply times 10 means shift the string one step left and add a zero "0" at the right hand side.
Then starting with 2 just multply by 2 ninehundred and ninety nine times. and sum the digits87.102.16.238 (talk) 16:43, 23 March 2008 (UTC)
Did that make sense?87.102.16.238 (talk) 16:37, 23 March 2008 (UTC)
(To go the whole hog you'd represent binary numbers using an array of booleans eg using true =1 false =0 so that eg an array of ten booleans would mean "0000000010" (binary) - of course you'd need an array of size 1000+ DONT go down this route here it's not neccessary and complicates the decimal sum at the end)87.102.16.238 (talk) 16:43, 23 March 2008 (UTC)
Wow! I made it finally! I'll paste the code of the string here; it's unoptimized, though :)
Dim i, j, m As Short, two1000, endstr As String, p As Byte, sum As Integer
two1000 = "000...01" '302 characters
For i = 1 To 1000
    For j = 1 To 302
        m = CInt(two1000.Substring(302 - j, 1))
        endstr = two1000.Substring(303 - j, j - 1)
        If m < 5 Then
            two1000 = two1000.Substring(0, 302 - j) + CStr(m * 2 + p).Substring(0, 1) + endstr
            p = 0
        Else
            two1000 = two1000.Substring(0, 302 - j) + CStr(m * 2 + p).Substring(1, 1) + endstr
            p = 1
        End If
    Next j
Next i
Then summing the digits of the string is easy. Thank you all very much who helped me implement this!  ARTYOM  16:36, 24 March 2008 (UTC)

One more thing, for anybody else who's interested in something like this: There may be libraries of code already written, to do arithmetic on large numbers. I know there are ones available for C and Perl and built in to Java. I don't know for a fact that there's one out there for VB, but there probably is. The downsides are that it'll be slower than using "machine precision" numbers, and it might be somewhat awkward to write (for instance, using the "GMP" library in C I would do "mpz_add(a,b,c)" instead of "a=b+c"). But it'll do the job. -- Why Not A Duck 00:17, 25 March 2008 (UTC)

[edit] How to program something like Netlimiter

How does one program a network traffic limiter like Netlimiter in Visual C++ (you can limit the bandwidth for each program as well as your whole computer)? I have no idea about how I would do that. --Taraborn (talk) 13:47, 23 March 2008 (UTC)

See Visual C++. This article might be able to help you. Nothing444 19:57, 23 March 2008 (UTC)
You'd replace the networking device driver with something that chainloads the original and throttles traffic while it's at it. :D\=< (talk) 04:44, 24 March 2008 (UTC)

[edit] Connecting two computers with network cables

I have two computers, one with an internet connection. I wish to share that connection with the second computer through a network cable. The computer with the internet is windows NT 2000 and the other XP. How can I do this? I have tried to simply connect them via a network cable but both give the error "a network cable is unplugged". I can confirm that both computers network cards work with other devices such as routers etc. Thank you for any help you can provide. Sincerely, John.

I believe you'll have to bridge the connection. However you go about doing that, I don't know. Useight (talk) 15:26, 23 March 2008 (UTC)
Firstly, to directly connect the 2 computers you'll need a crossover cable rather than the standard one you'd use to patch into a switch or router. As the name suggests, this is simply a matter of swapping some of the wires over en route, so adapters are readily available to stick on the end of "normal" Ethernet cables.
Secondly, you'll need to set the computers up to talk to each other, and specifically to share the Internet connection hosted by the Windows 2000 box. I've never used it, but I think what you need is Windows Internet Connection Sharing - the external links at the bottom of that article look promising...
Good luck! - IMSoP (talk) 15:34, 23 March 2008 (UTC)
Just FYI: Many modern Ethernet interfaces can be interconnected without needing a specific "crossover" cable. That is, they figure out that they're talking to another end interface and not a bridge and negotiate the required "crossover" action automatically.
Atlant (talk) 20:34, 23 March 2008 (UTC)
Well, you learn something every day! :) - IMSoP (talk) 21:00, 23 March 2008 (UTC)
With a router you can plug one into one port using ethernet and the other into another (also using ethernet). George D. Watson (Dendodge).TalkHelp 22:36, 23 March 2008 (UTC)
i can confirm this; last time i had to upgrade, i just unplugged the ethernet cable from the cable modem and plugged it into the new computer, then shared folders on the old computer and pulled them over from the new computer. And that was a pretty old couple of Dells. Gzuckier (talk) 19:07, 24 March 2008 (UTC)

[edit] What is DHE for torrent clients?

In my torrent client (bitcomet) i saw in the peers list some of the client types Bitcomet 0.93*DHEv2*,utorrent*DHE*. what exactly is this DHE? Does it help in increasing download speed? if so where can i get it?what exactly is the difference between bitcomet 0.93 & bitcomet 0.93*DHEv2*?

A quick look at the diambiguation page for DHE, and then at BitTorrent suggests this may refer to support for (or switching on the option of?) BitTorrent protocol encryption - DHE being an acronym for Diffie-Hellman key exchange, the first stage of many network encryption protocols.
But I could be completely wrong, of course. - IMSoP (talk) 15:20, 23 March 2008 (UTC)
I believe it stands for Data Header Encryption.. utorrent doesn't support DHEv2 but Bitcomet does. It's just one of many many client-specific protocol tack-ons like DHT (and Azureus's separate DHT network), PEX, UDP trackers, and secure announces :D\=< (talk) 16:29, 23 March 2008 (UTC)

[edit] .rar

hi,

as simply as you can tell me; if i downloaded a '.rar' torrent (music) how do i change it to normal .mp3 format, (using windows XP)......thanks--81.76.2.87 (talk) 20:46, 23 March 2008 (UTC)

A RAR file is a type of compressed archive, like a ZIP file (that is, files are stored within it and compressed to save space). You have to extract the files from it first. There are many programs to do this; I'm partial to 7-Zip on Windows. -- Consumed Crustacean (talk) 20:54, 23 March 2008 (UTC)
And if you didn't know that chances are that you didn't actually download the rar, you just downloaded the .torrent.. you need a bittorrent client and peers to actually download the archive :D\=< (talk) 20:59, 23 March 2008 (UTC)

[edit] Creators and/or owners of an HDTV logo

Resolved.

I have seen many places and things, including a TV Guide insert (years ago), the Samsung SIR-T151, and tek.advancedmn.com, show this logo or variants thereof. (It shows a white H on a blue circle, next to DTV with a checkmark-styled "V" in black.)

I was thinking it was made or owned by ATSC or some US company/ies; fontblog.de says it's from "RCA" (which would imply Thomson, or maybe even Audiovox). Can anyone confirm that (or otherwise) for sure? --an odd name 23:00, 23 March 2008 (UTC)

A quick search of the USPTO reveals a number of "HDTV" trademarks, none of which seem to be the one you're asking about. —mjb (talk) 17:29, 28 March 2008 (UTC)
The same fontblog.de page links to this RCA page; an archive of the page contains two TIFF versions of the logo. The RCA website has a Press Room; as of today, some of its pages, including this, link to thomsonmedialibrary.com, and searching for hdtv +logo yields the logo (and others), describing it as the "CEA logo for HDTV". Searching at CEA's site yields their "DTV Product Marks" page, which effectively directs usage inquiries to "CEA's product mark administrator". So I'm now pretty sure it's a CEA mark. --an odd name 00:33, 29 March 2008 (UTC)