technology dreams

67th year of computer networking

2006-12-06T23:04:00.000+01:00

In September 1940, Dr. George Robert Stibitz made first transfer of data in history to a computer using telephone line. He used teletype to send commands from Dartmouth College (a private academic institution in Hanover, New Hampshire) to computer based in New York. Let us to a bit calculation to see that now we are entering in 67th year of computer networking and see what a huge impact it has on modern society and world as we know it.

Perhaps the best analogy of computer networking would be the building of road or bridge over river, it has evolutionary role of enhancing economy and today right information in the right moment is foremost priority. As ancient Romans built roads and aqueducts we are now building information routes and connecting.

In this blog I also intend to write about things less known about networking, perhaps ones that are 'too scientific' for modern business related IT magazines. But, in order to understand networking or any science, we have to dive deep inside
ideas that were creating it during its evolution. So, since realm of ideas is realm of poetry - let us embark and enjoy on this voyage to still for many unknown land of computer networking.

update: I will start new blog about networking, so this will be the first post there also. Networking blog can be found on ---> http://networkprimer.blogspot.com

Self-organizing systems

2006-04-01T19:52:00.000+02:00

I was thinking about self-ogranizing systems. I am just reading paper The Meaning of Self-Organization in Computing by Francis Heylighen & Carlos Gershenson, which I found while surfing the excellent Cybernetics and System Theory site. Here is what they say:

|quote|Self-organization then means that a functional structure appears and maintains spontaneously. The control needed to achieve this must be distributed over all participating components. If it was centralized in a subsystem or module, then this module could in principle be removed and the system would lose its organization. Take the processor chip out of a computer and it becomes useless. Take any small piece of tissue out of a living brain (as commonly happens during brain surgery), and the brain will continue to function more or less like before.|end quote|

Has the time come to start forgetting Von Neumann's principles in computer hardware organization, I wonder?

Good old Amstrad Schneider

2006-02-17T23:59:00.000+01:00

In today's TV episode "Only fools and horses", Rodney was doing his homework on Amstrad CPC6128. When I was a kid, I had Schneider CPC464 (it is the similar computer with built in cassete deck instead of floppy disc). Those computers used some funny format of 3 inches floppy discs, not 3,5". I remember that I was dreaming about CPC6128 (keyboard is very nice, and floppy disc was a luxury thing in those years, and of course one always wishes something that he doesn't have). I remember it was pretty expensive to buy a floppy disc drive for CPC464, so cassetes were only solution that remained left to me :) But those were the nice times of learning the Z80 machine code to make your programs faster.

multiple inheritance

2006-02-16T23:59:00.000+01:00

Today I attended the first lecture on C++, and for the first time I heard about the possibility of multiple inheritance, something that was not possible to do in OOP language as JAVA. Well, in JAVA you can inherit subclasses from one superclass, but in C++ you can inherit subclass from two or more superclasses. It is still unclear to me what is the practical point of this - but it develops more freedom in language, and freedom is the best friend of creativity.

curling

2006-02-15T23:59:00.000+01:00

Today I watched Winter Olypics curling on TV. This sport looks boring in first seconds but I wanted to understand the beauty of it. And it is not possible to understand a sport when you do not know its rules. So, I tried very hard to understand the rules just by watching, but it was not easy, so I found nice site with flash animations that explains everything about curling. It is CURLINGBasics.com They certainly did much work to make all those animations.

circuit simulation

2006-02-14T23:59:00.000+01:00

Today I downloaded Electronics Workbench, it is about 200 MB big, so it took some time. As far as I can see it is nice and easy to use software. But I have problems with internet connection, so I cannot turn on Simulate feature, which is the reason why I needed this program. I hope I will solve this problem soon.

There is interesting TV course in practical electronics called "Reality TV for Analog Designers" A good place for learning.

wireless

2006-02-13T23:59:00.000+01:00

I started learning for another exam. Whole day I was pondering about different aspects of electrical resonance...uh! :)

old computers

2006-02-12T13:48:00.000+01:00

I was searching for old computers and found this very nice one from 1989. It is Apple Dynamac with 100 MB hard disc, 8 MB RAM and 2400 baud internal modem. The price was about nine thousand dollars at the time.

Transcendental PI and its decimals

2006-02-11T18:05:00.000+01:00

Imagine for the moment that you can draw a perfect circle. Now divide the circumference of that circle with its diameter. Do you know what number will you get as a result? Of course, it is PI=3.14159... there is no end and no repeating pattern in its decimals, and it is transcendental number. Babylonians believed that it is somewhat bigger than 3, they had approximation 3 and 1/8, 3.125 Egyptians believed it is 4*(8/9)^2. In geometry angle of 180 degrees is equivalent to PI radians.

German matematician Ludolph van Ceulen calculated first 35 decimals of PI. Those decimals are engraved on his tombstone in Leiden. In wikipedia we can read that one English matematician spend 20 years of his life to calculate about seven hudred decimals:

The English amateur mathematician William Shanks, a man of independent means, spent over 20 years calculating pi to 707 decimal places. His routine was as follows: he would calculate new digits all morning; and then he would spend all afternoon checking his morning's work. His work was made possible by the recent invention of the logarithm and its tables by Napier and Briggs. This was the longest expansion of pi until the advent of the electronic digital computer centuries later. In 1944, D. F. Ferguson (with the aid of a mechanical desk calculator) found that Shanks had made a mistake in the 528th decimal place, and that all succeeding digits were fallacious.

Interesting thing is that the first man who calculated one million decimals of PI, with help of computer has the same surname Shanks. It is Dr. Daniel Shanks and his team at the United States Naval Research Laboratory (N.R.L.) near Washington, D.C, and it is said that there is no family connection with William Shanks, despite the same surname.

There is a lot of interesting stuff connected to PI. Cadaeic Cadenza is 1996 short story by Mike Keith (the beginning is by E. Poe), and in its words it has first 3834 digits of PI. Full text of it you can find in this link. Japanese mental health counsellor Akira Haraguchi holds current world record of memorizing PI decimals. He can memorize 83431 PI decimal places. If you wish to calculate huge number of PI decimal places, you can use PiFast program. And if you want to search for string of numbers (perhaps for your birthdate) you can click here, there is a very fast PI online searching method.

Today is 11th February 2006. I'll try to search for string of decimals 11022006 (DDMMYYYY format). There is such string in number PI, after 115,903,340 decimals (115 million hey :)

XX Winter Olympics Torino 2006

2006-02-10T23:10:00.000+01:00

Festival of joy and peace tonight in Torino. I always adore Olympic games, whether summer or winter, because great part of of humanity is watching the opening ceremony in joy, and you can feel peace and goodwill is spreading all over the planet. Visit XX Winter Olympics in Torino official site for more details about the games. I hope we will all enjoy in the beauty and universal harmony of Olympic games in days to come...

new beginning

2006-02-09T23:17:00.000+01:00

I begin to study C++. I was surfing the web today on the subject and found many hidden tutorial treasures :) And a list of libraries, C++ glossary and FAQ on style and technique, on homepage of Dr. Bjarne Stroustroup, creator of C++.

Over with JAVA exam

2006-02-08T20:16:00.000+01:00

I passed the exam. What to say :)

IDE

2006-02-07T23:59:00.000+01:00

In order to do programming you need compiler, interpreter or assembler, depending on what are you going to do. I downloaded two C++ IDE's, DevC++ and OpenWatcom, and I will see which one suits me best. IDE is short of Integrated Development Enviroment, and beside compiler it has many useful tools, such as source code editor and debugger, so it makes your life easier.

a new begining

2006-02-06T23:59:00.000+01:00

Today I was searching for C++ tutorials on the web. There are quite a few interesting ones, some explaining features that I couldn't presume do exist. Freedom is greater in C++ than in JAVA, but so is responsibility - one has to be careful when writing code, nothing is beyond C++ reach if I understood it well. Today, my dentist friend told me about beauty he experienced when he was learning for his physiology exam years ago. I could understand him, the same is with programming - beauty of understanding processes and mechanisms - a sheer beauty of this common "system methodology" (or cybernetic if you prefer) topic...

nice news

2006-02-05T23:59:00.000+01:00

I think I have done it well, but you know about exams - you can never know until you see the results. And results will be in Wednesday, hopefully.

In the meantime, if someone is inspired to learn more about the concepts of OOP (Object Oriented Programming) there are nice articles on the web. Learn about OOP in JAVA, or in C++, or in C# ...

Scio me nihil scire :)

2006-02-04T23:59:00.000+01:00

I've been working whole day - but now I am both puzzled and confused about things that I reckoned I understand well. This exam is the highest level of mental abstraction I've encountered so far - so great struggle will be tomorrow... wish me luck :)

first part is over

2006-02-03T20:17:00.000+01:00

Today I went out to see the results of the first part of my JAVA exam. And I passed!!! I cannot believe, it was so hard. Now, I have to prepare for the second part in few days. What to say, I like impossible challenges like this :)

Universal Serial Bus

2006-02-02T23:59:00.000+01:00

Don't know much about USB, but when I see picture like this - I get the inner urge to find out more about it :)

USB vaccine drive

2006-02-01T15:30:00.000+01:00

Company IOCELL produced USB flash drive that is functioning as an antivirus vaccine. Partition of this disc contains antivirus software, which is updated whenever attached to internet (service is free for two years after the date of purchase) Different memory sizes are available (from 128 MB up to 4 GB and USB is 2.0 version which is compatible with older 1.1) When you plug this drive in the computer's USB port - it automatically runs antivirus engine, and monitors the processor and memory in real time. You can use this disc as ordinary USB drive, and you can store on it software and applications from C2 remote server. Vaccine drive ensures the integrity of stored data against viruses, spyware and other malicious codes. One professor of mine refuses to save his lectures on student's flash drive (he demands CD to burn them), because he is afraid that there could be viruses inside. It seems that this VaccineDrive is exactly what his students need, perhaps he would have more faith in them then :)

Details about this product you can see in the pdf brochure.

electronics for real

2006-01-31T23:59:00.000+01:00

Now, practical electronics attracts you - you want to solder some components and to see whole thing is working. But what to do? Of course you can make a circuit with switches and little bulbs, so you can play with that. Problem is - that will be boring unless you are under 10 years old. Well, but there is something interesting one could do, and for it you just need two bipolar transistors, two capacitors, four resistors and a battery - and two LED's (Light Emitting Diodes) just in order to see that something is happening. This circuit in electronics is called astable multivibrator - it means that pulses will be generated so LED's will switch on and off alternately in periods of time that you can control by choosing adequate capacitors and resistors. There is nice java applet that demonstrates how this works.

When I first made this circuit, I used components from one old TV. And it worked. And I was so amazed that something that I soldered is actually working :) As far as I can remember I used 4.5 V battery.

If you want to learn more what is actually happening, there is nice article here. And I found an applet that helps you set components on protoboard (if you have one). No need for soldering in that case. However on the picture above, you can see improved variant of this circuit which is using integrated circuit 555 timer.

spectrum analyzer

2006-01-30T23:59:00.000+01:00

Here is how spectrum analyzer looks like for those who have never seen it in real. Of course, you can find more pictures of those instruments.

filters

2006-01-29T23:59:00.000+01:00

Yesterday I said that we can somehow avoid interfering signal, but I did not specify how. Of course, it can be done by using electronic filter. Most simple filters are those in RC, RL, LC or in RLC circuits. If we keep in mind relation of impedance to frequency change of such combinations we can visualise easily what kind of signals will be filtered.

To quote from Wikipedia:

A filter in which the signal passes through an inductor, or in which a capacitor provides a path to earth, therefore presents less attenuation to low-frequency signals than high-frequency signals and is a low-pass filter. If the signal passes through a capacitor, or has a path to ground through an inductor, then the filter presents less attenuation to high-frequency signals than low-frequency signals and is a high-pass filter.

Topic about filters is a very rich one, so I guess I'll dedicate to it some more posts in the future as my knowledge on that improves. Let me say for now that in real life you are using electronic filters when you are changing (potentiometer) equalisers on your hi-fi. Filters can be used in visual arts as in beautiful picture Utopia by Tony Stanovich (above)

Fourier Transform

2006-01-28T17:47:00.000+01:00

I remember the first time I encountered the idea of Fourier Transform, I was very delighted. It was in grammar school, and of course - not in the detail - just one sentence: any complex signal can be presented as (in)finite sum of sinusoidal signals of different amplitude and different frequencies (harmonics)! But not whatever frequencies - just those ones that are integer multiple of fundamental frequency. Wow, try to imagine that for a second. You take a microphone and record a voice signal which is very complex - and you can translate that signal into sum of very graphically different sinusoidal signals. Amazing, but why is it important? Now, we all know we can see the shape of electrical signal in time, on device called oscilloscope. For example you are measuring signal somewhere, and you expect some kind of shape, but you see on the scope something different than what you expected. What is happening? That means some other signal is interfering with your signal. It is possible to cut off somehow that interfering signal, but first you have to know its frequency and amplitude. In that way you will identify its source. It is practically impossible to distinguish that on time domain oscilloscope scale. We need Fourier Transform which turns time domain in frequency domain - there we will see all that sinusoidal signals as vertical lines long proportionally to amplitude, and on x axis you can read their frequency. Then it is very simple to identify source of interfering signals. Device that can display frequency domain is called spectrum analyzer. It is rather expensive device comparing to oscilloscope, so if you have signal in time, you can apply to it FFT on PC, and see how it looks like in frequency domain without buying spectrum analyzer.

You can try to see how it looks like. There are many programs that can do that, for example this 3D scientific calculator, and there are FFT libraries for different programming languages to download. And if you are good in electronics you can even build an analyzer from retro kits, so they say, I haven't tried it.

As for 3D scientific calculator, install and start it. Then choose Analyze Raw Data --> Transform --> Microphone Input. Try to tap microphone with your finger, see pulse like signal in time domain, and see what happens in frequency domain below the first graph (all happens in real time). Then, if you are in mood, you can sing something, and see what happens :)

250th aniversary of Mozart's birth

2006-01-27T23:09:00.000+01:00

Musical genius from Salzburg Wolfgang Amadeus Mozart lived only 35 years, but left about 626 works, and even more to it - his name remain engraved with the golden letters in history of mankind. We do not know where is his grave, but his music escaped open jaws of world's forgetfulness and found its eternal home in musical notebooks all over the world, and in the dreams of those who play it or listen to its splendours.

Today people in Serbia celebrate Saint Sava day, dedicated to medieval prince Rastko Nemanjić, son of founder of Serbian medieval state Stefan Nemanja. Prince Rastko should have inherited the throne, but he had different plans - and went to the monastery (where he took new name Sava). There are not many people in history who renounced such great political power and wealth and went to live life of discipline in solitude (later his parents joined him too) There is, of course, a great example of prince Siddhartha who renounced everything in order to find a way to cessation of human sufferings.

On the picture you can see detail of the Typicon of Kareya which St. Sava wrote in 1199 to determine monastic way of life in monastery Hilandar (Chilandar)

eh, those supercomputers

2006-01-26T16:18:00.000+01:00

Have you ever wondered what is the most powerful supercomputer at the moment? Top500 site is a good place to look answers for such questions. We can see that currently the leader is IBM BlueGene/L with unimaginable 280.6 TFlops and 131072 processors. What does that /L in the end mean? Well it means that currently most powerful computer in the world is operated by (my beloved) GNU/Linux operating system.

But why such 'biological' name? Apart from their common use in nuclear war simulations and climate prediction, supercomputers found their application in predicting the 3D structure of protein folding. As you probably know, proteins are chains of aminoacids. The code which says what is the sequence of amino acids in protein chain is encoded in DNA. Knowing that sequence and with help of a supercomputer, we can understand many processes and find help in inventing new, more efficient vaccines. Since DNA is consisted of genes - hence the name of a supercomputer! Of course there are another ways to help this protein-folding research, and that is by using a grid computing network. 'Rosetta at home' project does that, but more explanation about it I will give in some of next posts.

marathon run

2006-01-25T10:56:00.000+01:00

Browsing Wikipedia, I learned two very interesting facts:

Dr. Turing was an excellent marathon runner. His personal best time for marathon was 2 hours, 46 minutes, 3 seconds which is only 11 minutes slower than the winner in 1948 Olympic games!!! It is so nice to hear that world class scientist was excelling so much in long distance running.

Dr. Shannon invented a rocket-powered pogo stick. Whoo hoo!!! Man, I want to try it. And I am sure that Wile E. Coyote would need it badly :)

This morning the postman brought me a letter from Okinawa. After enjoying for a few moments in beauty of Kanji letters, I opened it - and lo, there are little shells from a beach there! Thank you, my dear friend, shells are so subtle and delicate - they remind me of a beach in introductory chapter of Arthur C. Clarke's "Songs of Distant Earth" (which is the first novel I ever tried to read in English, long ago). In one word, it is like a dream. Arigatou :)

computer chess

2006-01-24T15:13:00.000+01:00

As for computer chess it is very interesting to learn how it all started. If we say that Dr. Shannon is founding father of telecommunications and information technology, for sure we can say that the founding father of computer science is Dr. Alan Turing (Princeton PhD). Dr. Turing was a legend from WWII because he
devised electromehanical machine which could find settings for german Enigma ciphering machine. If Enigma code had not been deciphered during the war who knows who would win the WWII. Exact history of computer chess you can find in this timeline and nice article too on chessbase page. What is most interesting for me is so called Shannon Number. He was first to estimate game tree complexity in chess. Now we know that the number of legal positions goes up to 10exp50. It can be compared to number of atoms in this Universe (between 4×10exp78 and 6×10exp79). And what do you think how much time would a computer need to calculate every position? It's next to impossible! :) So he wanted to find a sort of pruning technique, algorithm that would not take in account every line in chess tree, but only potentionally strong ones. Of course, he needed some function that would estimate "weight" of a position - so again he was to objectivize something that was abstract at the time. What did he do? He assigned usual material numbers to all figures (1 to pawn, 3 to bishop, 5 to rook and so on), and added his estimations of positional features, like adding 0.1 to each legal move (mobility factor), minus 0.5 for every doubled, isolated and backward pawn, and 200 points for checkmate. Thus he made an evaluation function in which he substracted the value of the black position from the value of the white position. Now he had something upon which algorithm could decide for every move, so he applied minimax procedure for chess.

First chess program that really played on computer was programmed in Los Alamos National laboratory, on famous Univac MANIAC I machine. Because of computer's humble speed of only 11 kHz, bishops are excluded and table was 6x6 instead of 8x8. In that way it needed 12 minutes to search 4 moves deep. If we add two bishops as in real chess, for 4 moves it would need 3 hours! It was a computer from good ole times that has 2400 vacuum tubes. MANIAC is abbreviation of Mathematical Analyzer, Numerical Integrator, and Computer or Mathematical Analyzer, Numerator, Integrator, and Computer and it played chess in 1956. Programs that emulate this 6x6 Los Alamos chess can be found here.

Dr. Claude Shannon

2006-01-23T15:29:00.000+01:00

Telecommunications are all around us. WWW, mobile phones, satellite comunications. They are affecting everything, from everyday lives to world politics. But who is the founding father of electrical communications - Claude Shannon, of course! American (MIT PhD) mathematician and electrical engineer who in 1948 wrote his famous scientific work Mathematical Theory of Communication, and so everything started. Perhaps you wonder how analog signal (which is continuous change of voltage in time) is transformed into digital signal (sequence of bits). Without that there would be no CD's, DVD's, digital telephony and GPRS, no internet and of course we would listen to LP's (someone perhaps likes it that way). Well here is the sampling theorem that explains necessary preconditions. Shannon is very interesting to me because he is the first man who said that information can be measured. I always thought that information is something abstract, but he made equation in which objectivized quantity of information. It is important because now we can calculate the needed channel bandwith for some source to transmit a message.

Although in telecommunications professor Shannon is considered to be a science saint, very few people in ICT sector know that he is the first person to program computer to play chess. I asked some famous professors and they didn't know that. Shannon wrote paper "Programming a Computer for Playing Chess" in 1950. More details I will give in next post.

IBM 1403 - a musical printer

2006-01-22T17:02:00.000+01:00

It seems that someone was musically oriented among engineers, when he noticed that some combinations of characters produced "tones" of different pitch and duration, while IBM 1403 (an old printer from sixties) was printing. Soon people realized that even the type of paper affects the music - and whole new art was born. Printer IBM 1403 was operated by first massively produced digital business computer IBM 1401 (introduced in 1959), and music was saved on punched cards. If you wish to hear masterpieces of this early digital art, you can find mp3's here. Sounds interesting, don't you think...

This printer took part in Kubrick's movie Dr. Strangelove, and you can read more about this ancient printer in Wikipedia.

dreams in silence

2006-01-21T05:02:00.000+01:00

Hello world :) My professor once said that engineering has nothing to do with poetry. I believe she was wrong. How can we make technology if we do not know how to dream? Just try to find ICT & computer magazines from 80's, and see how much enthusiasm people had about 8-bit machines...yes, those running BASIC interpreter. Or when they wrote text adventure games (interactive fiction) for computers such as PDP-10 in 1975, or even for famous pocket HP41C (which seemed impossible to do). Can you be a poet and dream not? Never. Are there no dreams in technology? Impossible. Famous inventor of alternate current, Nikola Tesla, arrived in USA with a book of his poetry! Dear professor, just think it over again...

And this blog I dedicate to technology and dreams of past, present and future.