Jos Kirps's Popular Science and Technology Blog
Spend your Holidays at the Chernobyl Nuclear Power Plant
March 03, 2009About 23 years ago, on April 26 1986, reactor 4 at the Chernobyl plant exploded after a safety device test during the reactor shutdown rendered the core unstable. The test had been run by an unexperienced crew who had overrun and disabled numerous security systems and had thus ignored many security rules.
After the disaster a protective box was placed over the wrecked reactor, which has become known as the "sarcophagus". It was never designed to last for the 100 years needed to contain the radioactivity found within the remains of reactor 4, and experts even fear that it may collapse one day. This is why a new shelter is planned to be installed within the next few years.
Most people working at the power plant lived in Pripyat, a city located only a few miles from the plant that had been built for the power plant workers and their families. After the accident the 50,000 habitants of Pripyat as well as another 85,000 people within a 30 kilometer zone (the so called "zone of alienation") had to be evacuated.
Today Pripyat is an abandoned city, although some people living in the villages surrounding Pripyat returned to their homes after the accident and still live there today.What most people do not know is the fact that the nuclear plant was not shut down after the accident. The three remaining reactors continued operating, and shortly after the disaster the city of Slavutych was constructed to replace Prypiat. Despite the high levels of radiation thousands of people still worked at the Chernobyl plant until it was finally shut down in December 2000 after massive pressure and payments by western nations. Reactor 2 had already been shut down in 1991 after another severe accident which seriously damanged its reactor building.
Over twenty years after the accident radiation levels are still high in Pripyat, although they are no longer considered to be life threatning for visitors. The core of the reactor 4 still contains a large number of highly radioactive materials, but these don't have direct contact to the atmosphere.
It's now even possible to visit Pripyat for everyone as tourist offices in Kiew offer visits to the abandoned city. The main roads have been decontaminated and most buildings are open to tourists, although it's not recommended to stay too long inside rooms that have not been decontaminated. The bus will even take you to the nuclear power plant so that you may take a closer look at the sarcophagus.
There are still people working at the power plant today, their job is to keep an eye on the shut down reactors and to fix the sarcophagus until a new steel containment structure will be ready to replace it. Sometimes visitors are even allowed to enter the nuclear plant, and on rare occasions you may also enter the control room of reactor 4.
Entering the sarcophagus is, of course, strictly prohibited for tourists, although some workers of the plant enter it on a regular basis to check its structure. Workers are only allowed to remain a few minutes at a time inside the sarcophagus as radiation levels are still quite high here, even if the core itself has been covered by thousands of tons of sand, lead, clay, boron and concrete.
Bookmark This
permalink | 0 comments
Happy Birthday, Apple Macintosh!
January 24, 2009Exactly 25 years ago, on January 24, 1984, Apple Computer launched the first Macintosh computer. It was the first commercially successful computer featuring a mouse and a graphical user interface (GUI). The Macintosh was introduced by the famous "1984" television commercial by Ridley Scott which aired during Super Bowl XVIII.
The original Mac was designed by an Apple development team in the late 1970s, inspired by workstations created by Xerox employees at the Xerox PARC (Palo Alto Research Center). The team was lead by Apple founder Steve Jobs and included famous developers such as Jef Raskin and Bill Atkinson. The computer featured a Motorola 68000 processor running at 8 Mhz, 128 KB RAM, 64 KB ROM, a 9-inch 512x342 pixel monochrome display, a keyboard and a mouse. It also came with two applications, MacWrite and MacPaint.Shortly after the successful launch of the Apple Macintosh, founder Steve Jobs left the company in 1985 after disputes with the new CEO John Sculley. Jobs then founded the NeXT company and started working on workstations based on NeXTstep, a UNIX-like operating system.
In 1985 Apple introduced the LaserWriter and software like MacPublished and PageMaker marked the debut of WYSIWYG (What You See Is What You Get) and the desktop publishing revolution. Soon more professional applications such as Macromedia FreeHand, QuarkXPress, Adobe Photoshop and Illustrator were released and helped the Mac to become the number one platform in the creative business.
In 1987 Apple launched the first upgradable Mac, the Macintosh II. It featured a 16 MHz Motorola 68020 processor, Color QuickDraw (a graphics library that supprted color, various display sizes & multiple monitors) and expansion slots.
Early releases of Microsoft Windows never really threatened the Mac platform, but in 1990 Microsoft finally managed to launch a usable version with Windows 3.0. The launch of System 7 helped to strengthen Apple's position as a GUI market leader, nevertheless they were forced to lower Macintosh prices to remain competitive.
In 1994 Apple successfully switched from the Motorola processor architecture to the PowerPC RISC platform. Software written for the Motorola 68000 architecture could still be executed as the PowerPC version for System 7 included a Motorola 68k emulation software.
In the mid 1990s Apple got into serious trouble. The launch of Windows 95 considerably lowered Apple's market share as it was now possible to get an Apple-like OS without having to buy an expensive Macintosh computer.
Apple also didn't manage to finalize their next-generation operating system, MacOS 8. After it became clear that MacOS 8 would never be completed, Apple had to look for a MacOS successor outside the company. They finally bought NeXT, the company Steve Jobs founded after his departure in 1985. As a result, Steve Jobs returned to the company.
In 1998, Apple introduced the all-in-one iMac, which turned out to become a phenomenal success and helped the company to return to profitability. It was followed by the iBook protable computer and updated desktop computers.
MacOS X, the UNIX-like MacOS successor based upon the NeXTstep OS, was finally released in 2000 and 2001. It introduced a modern OS foundation as well as the all new Aqua user interface. Classic MacOS 9 applications could still be used as MacOS X included a copy of MacOS 9 running in a secured "classic box".
In 2006 finally switched to the Intel x86 platform, abandoning the PowerPC. Intel Macs can still execute PowerPC applications as MacOS X for Intel Macs includes a PowerPC processor emulation software called Rosetta, but they no longer support the classic box and MacOS 9.
During the past few years Apple managed to regain some of the market share it lost during the 1990s, and today the company is shipping more Macs than ever before.
Bookmark This
permalink | 0 comments
Merry Christmas and a Happy New Year!
December 24, 2008
Bookmark This
permalink | 0 comments
CorneliOS becoming more and more successful...
September 29, 2008During the weekend I checked my stats and noticed that CorneliOS is now the most successful software project I ever started, powering multiple PR5, PR6 and Alexa Top 500k websites. Over 8000 users worldwide are either using the software directly or are subscribed to CorneliOS powered services, most of them are from the US, the UK, Australia, India and Germany.
New CorneliOS based projects are emerging, so I think I'll soon create a non-profit label for free and open source software, this label shall then be used for CorneliOS based software as well as for derivate applications and software works...
Bookmark This
permalink | 0 comments
Why I hate Cuil
July 31, 2008On Monday a new search engine has been launched, it's named Cuil but pronounced Cool (huh?) and it got a lot of really bad reviews which made me really happy.
So why do I hate Cuil?
Well, a few months ago we started noticing more and more traffic on our company websites, caused by a crawler called Twiceler. Twiceler was run by a company called "Cuil" and claimed to be some kind of an experimental search engine robot. A few days later the same crawler also started affecting my personal websites.
The Twiceler bot is probably the most stupid crawler I've ever seen, it just downloads everything it can find and it seems that it just won't ever stop. If there's a page using dynamic input in a URL (a calendar for example) it will download the same page 100,000 and more times, simply by following all kinds of dynamic links it can find without using any kind of intelligent limitation.
By downloading thousands of pages per hour on each website it can cause an incredible traffic on a server, and dynamic scripts (written in Perl, Python or PHP for example) start causing an immense CPU load that may even take your entire server down (as reported by several webmasters). Twiceler is really harmful and can cost both money and downtime. A well written crawler such as Googlebot or Slurp (Yahoo) would never affect a website in such a malicious way.
After googling for Twiceler we found out that many webmasters experienced such problems with Cuil. Of course we thought that such a crappy crawler - which doesn't seem to care about similar content, website performance, bandwidth and traffic costs - had to be some kind of a malicious spam bot.
As the stupid Cuil/Twiceler bot just won't stop the first thing you'll do as a webmaster or system administrator is setting up a robots.txt file which tells Twiceler not to index any more pages (or at least blocks some of the directories that shall not be indexed, such as dynamic scripts for example).
Cuil claims that their Twiceler crawler respects the robots.txt file, but even days after setting it up nothing changed, the damn bot continued indexed anything it could get and completely ignored all robots.txt rules (google for Twiceler and you'll see that this is what other webmasters are experiencing too).
So finally we blocked the entire Cuil bot on our servers, just as many other people recommend in webmaster forums. On our company servers we blocked all incoming connections that could be identified as a Cuil/Twiceler bot, on my personal websites I blocked all of Cuil's IP addresses using .htaccess files.
It was a funny moment when the Cuil search engine went live on Monday and they claimed to have the world's biggest index. Of course they have! Their damn bot seems to be indexing each dynamic web page a million times, no matter if it's always the same content of if you're clearly saying that this page should not be indexed at all (via robots.txt).
Maybe this also explains the poor quality of their search results - their index may be the largest on this planet, but it's probably full of crap and duplicates.
If you're a webmaster/website owner and you're currently experiencing high bandwidth or traffic problems, then you should check your access_log because there's a good chance that your problems are caused by Cuil. If this is the case I can just recommend to block all of Cuils IP addresses on your server because that seems to be the only thing that really works.
To finish I'd like say that I think Cuil should start focusing on the quality of their algorithms and their content instead of completely relying on the marking of doubtful numbers.
Bookmark This
permalink | 4 comments
Now displaying 5 of 98 blog entries on page 1 of 20
Select a page: next | last
1996-2009 Jos Kirps | All rights reserved | Privacy Policy | Site Map | Rate this site
