Tuesday, October 13, 2009

Homi Jehangir Bhabha (1909-1966)

Homi Bhabha was born on 30 October 1909 in Mumbai. Son of a
barrister, he grew up in a privileged environment. In Mumbai he attended the
Cathedral & John Connon School and then Elphinstone College, followed by
the Royal Institute of Science. After passing the Senior Cambridge Examination
at the age of sixteen, he joined the Gonvile and Caius College in Cambridge
with an intention to pursue mechanical engineering. His mathematics tutor
was Paul Dirac, and Bhabha became fascinated with mathematics and
theoretical physics. He earned his engineering degree in 1930 and Ph.D. in
1934.
In 1937, together with W. Heitler, a German physicist, Bhabha solved
the riddle about cosmic rays. Cosmic rays are fast moving, extremely small
particles coming from outer space. When these particles enter the earth’s
atmosphere, they collide with the atoms of air and create a shower of electrons.
Bhabha’s discovery of the presence of nuclear particles (which he called
mesons) in these showers was used to validate Einstein’s theory of relativity
making him world famous.
When the war broke out in Europe, Bhabha was on a holiday in India.
In 1940, C.V. Raman, then head of the Physics Department, Indian Institute
of Science, Bangalore, persuaded Bhabha to join the institute as a Reader in
Physics and Bhabha decided to stay back in India. In 1941, Homi Bhabha was
elected Fellow of the Royal Society, London, in recognition of his contributions
to the field of cosmic rays, elementary particles and quantum mechanics.
Bhabha soon realized the need for an institute fully devoted to
fundamental research, and wrote to J.R.D. Tata for funding. This resulted in
the establishment of the Tata Institute of Fundamental Research (TIFR) in
Mumbai in 1945, with Bhabha as the Director, a position he held until his
death. In 1948, Homi Bhabha was appointed the Chairman of the International
Atomic Energy Commission. Under his guidance, nuclear reactors like the
Apsara, Cirus and Zerlina were built. He gained international recognition for
his excellent work and served as the President of the first United Nations
Conference on the Peaceful Uses of Atomic Energy, which was held in Geneva
in 1955. He was the President of the International Union of Pure and Applied
Physics from 1960 to 1963.
A multi-faceted personality, Bhabha was immensely fond of music,
painting and writing. Some of his paintings are displayed in the British Art
Galleries and the TIFR art collection today is rated as one of the best collections
of contemporary Indian art in the country.
He is the recipient of the Adam’s Award, Padma Bhushan, an Honorary
Fellow of the American Academy of Arts and Sciences and Foreign Associate
of the National Academy of Sciences in the United States.

WHAT IF..?

1-What if ........the wire of a UPS(uninterrupted power supply) is connected to one of its own sockets and the UPS is turned on???
Will the UPS charge, or will it beeping?
2- Why must not a spike buster be connected to the output of UPS?



article contributed by: TARUN KUMAR.E. , ECE, MRIET.

Friday, October 9, 2009

u r special

DEAR READER,
In a classroom of so, the speaker asked,"who would like this hundered rupee note?"Hands started going up.He said,'I'm going to give this to one of you but first,let me do this."He proceeded to crumple the note.

He then asked the crowd,"who will want this?"And he dropped it on the ground and started to grind it into the floor with shoe.He picked it up,now all crumpled and dirty."Now who still wants it?"Still hands went into the air.

"My friends you have learned a very valuable lesson.No matter what I did to the money.You still wanted it because it did not decrease in value.It was still worth a hundered.Many times in our lives,we are dropped,crumpled and ground into the dirt by decisions we make, and the circumstances that come our way."

"Do you know you are unique?Taking into consideration the past hundered years and in the future century, no one had or will have your fingerprints, your lip prints, your ear to toe prints.Your DNA is unique.Doctors have shown that the composition of your blood is peculiar to you.You are,infact,a special individual with a capacity to achieve great things."

"Do you remember at school,for example,thinking:how can I do that when ever you were instructed to use a new skill?Yet each time,after pushing yourself,you 'discovered' you had the ability - you even enjoyed it.Once accomplished you never forgot how to ride a bicycle, you had the ability.But you had to draw on yourself as a child to ovrecome the inevitable falls.The secret is that this potential must be called upon.Those who give up,fail in their lives.This is known as 'mind limitation'.

"we feel worthless, but no matter what has happened, or what will happen you will never loose your value. You are special,don't ever forget it."
For an instance let me give you, few questions which you hear almost at a frequency of every day:
01. Why can't you be good for a change?
02. Why are you so selfish?
03.Why do you have to fight with everybody?
04.Why can't you be like other children?
05.Why must you interrupt everybody?
06.Why can't you keep your mouth shut once in a while?
07.Why are you slow?
08.Why are you so stupid?

It is said 12,000 such negative suggestions (suggestives) are confronted by a child in span of 15years.This greatly affects the self-esteem,learning and other skills,thus hampering academic performance, in most cases.
Just remember as the currency does not diminish in value despite being crumpled,stamped and thrown about, the human value never changes adversely despite several such shabby treatments.
Students should learn to overcome this problem, to become a winner!
Blame and guilt are cry baby words; lets get them out of our talk about edu.
Let us consider the word "responsible' and 'commitment'.

Friday, August 21, 2009

Tech groups join fight against Google books

Amazon, Microsoft and Yahoo! are lining up to fight Google over the search giant's plans to commercialize a huge digital library of books.

The leading technology companies are joining a coalition of library associations and charities called the Open Book Alliance in opposing Google's ambitious book scanning project.

In the first united response to the growing might of Google, they want to challenge Google's class-action settlement with authors and publishers.

Google reached a settlement last year with the Authors Guild and Association of American Publishers on a copyright infringement lawsuit that they filed in 2005 over Google's plan to scan millions of books and put them online.

Under the settlement, Google agreed to establish an independent "Book Rights Registry", which will provide revenue from sales and advertising to authors and publishers who agree to digitise their books.

The settlement, under which Google has agreed to pay $125 million (£75 million), is already facing anti-trust scrutiny from the Justice Department and awaiting court approval. A hearing is set for October 7 in the US District Court in New York.

The system will allow authors and publishers to register works and receive compensation from institutional subscriptions or book sales. Authors and publishers would get 70 per cent from the sale of these books with Google keeping the remaining 30 per cent.

Critics say that the deal gives Google the unimpeded ability to set prices for libraries, once they scan books and put them on the Internet. They also say that it would also allow Google — and only Google — to digitise so-called orphan works, which could pose an antitrust concern. Orphan works are books or other materials that are still covered by US copyright law, but on which ownership rights are not clear.

Google took issue with the criticism. Gabriel Stricker, a spokesman for the company said: "The agreement is not exclusive. If improved by the court, it will expand access to millions of books in the US.

"The agreement stands to inject more competition into the digital book space, so it's understandable why our competitors would fight hard to prevent more competition."

Gary Reback, an anti-trust lawyer in Silicon Valley who is acting as counsel to the Open Book Alliance, told the New York Times that the book deal "has enormous, far-reaching anti-competitive consequences that people are just beginning to wake up to".

Mr Reback, who helped to persuade the Justice Department to file its anti-trust case against Microsoft in the 1990s, said that the group includes the Internet Archive, a San Francisco non-profit organisation that maintains a digital library of websites.

Peter Brantley, a director of the Internet Archive, said that the Special Libraries Association, the New York Library Association and the American Society of Journalists and Authors were planning to join the group.

The American Civil Liberties Union, the Electronic Frontier Foundation and the Samuelson Law, Technology and Public Policy Clinic of the University of California at Berkeley recently wrote to Google's chief executive, Eric Schmidt, expressing concerns about privacy aspects of the deal.

"Given the long and troubling history of government and third-party efforts to compel libraries and booksellers to turn over records about readers, it is essential that Google Books incorporate strong privacy protections in both the architecture and policies of Google Book Search," they said.


Saturday, July 25, 2009

LIFE IS NOT PLAIN

A TRUE LIFE INCIDENTIt was wee hour of the day, I woke up and started with my daily exercise for about half an hour and started with my daily chore!This was a special day for me; I have a driving license test at NAGOLE RTO. My slot was confirmed at 10:00 am to 11:00 am! .I was late by 20 minutes. I didn’t know that I’d to be there one hour before the time of report. Went straight into the office in order to confirm my booking but the official there was very strict. He refused to my late coming. He made me stand for one hour, all the time gazing at me if I would give him money or not. I didn’t give him a bug. Somehow I was able to manage getting permission for driving on a track. Government officials make us to move all the way and our files move from one place to another pointing out on missing. Even I thought that not government offices are dumb but today I’d realized that all resources of govt. offices work only with black money. It’s not how legal you are, it is that how much you pay to the official, to get your work done. In olden days, they used to take money after the work is done, but now-a-days work is accelerated with the quality of fuel you pour.I forgot to take insurance of my bike. As usual constable didn’t allow me to take the test. I waited for half an hour, he made me roam like a mad dog, to table A, again from him to this guy, again from this guy to table C, and finally I was fed up and tiered of that. All this way an agent was observing me and came to me, took my documents, signed and asked me to take the test. I happily rushed to my track which was slippery (due to rain). I had to make “8” and some curves and come out! Actually I was told that we can put our leg ones anywhere in the track, I put my leg at my final position 10 seconds before leaving the track, was disqualified.After all these, I requested constable sitting near my track inspecting me about why I’d put my leg, he has refused to listen to me. There was one gentle man who came with an agent paying him some bugs, got through the track placing his legs twice on the ground but even then was selected and he is going to receive his license within 7 days.I’d got to book my slot again and reappear for the test wasting more money. Finally I left the place and in my way back home, traffic constable stopped my vehicle asked me to show my license. I’d only LLR with me, got to pay him 300 bugs. I said I have only 100 bugs and gave him that amount.I’VE NOT TOLD THIS TO YOU TO GAIN YOUR SYMPATHY. MY IDEA IS HOW BEST EVER YOU ANTICIPATE, THERE ARE CERTAIN LOOP HOLES OR TWISTS OR JUNCTIONS IN YOUR PLAN, WHICH YOU MAY OFTEN NOT KNOW THEM THAT THEY WOULD ARAISE! HAVING LEARNT HOW TO MANAGE THINGS, MAY POSSIBLY AVOID CONFUSIONS IN YOUR BATTLE OF LIFE!!!!
AVOID BRIBING, ASK FOR CHALLANS IF FORCED TO GIVE MONEY.RESPECT THE LEGAL SYSTEM..

Wednesday, February 18, 2009

Tunnelling Effect

In quantum mechanics, quantum tunnelling (or the tunnel effect) is a nanoscopic phenomenon in which a particle violates the principles of classical mechanics by penetrating a potential barrier or impedance higher than the kinetic energy of the particle.[1] A barrier, in terms of quantum tunnelling, may be a form of energy state analogous to a "hill" or incline in classical mechanics, which classically suggests that passage through or over such a barrier would be impossible without sufficient energy.
On the quantum scale, objects exhibit
wave-like behaviour; in quantum theory, quanta moving against a potential energy "hill" can be described by their wave-function, which represents the probability amplitude of finding that particle in a certain location at either side of the "hill". If this function describes the particle as being on the other side of the "hill", then there is the probability that it has moved through, rather than over it, and has thus "tunnelled".

By 1928, George Gamow had solved the theory of the alpha decay of a nucleus via tunnelling. Classically, the particle is confined to the nucleus because of the high energy requirement to escape the very strong potential. Under this system, it takes an enormous amount of energy to pull apart the nucleus. In quantum mechanics, however, there is a probability the particle can tunnel through the potential and escape. Gamow solved a model potential for the nucleus and derived a relationship between the half-life of the particle and the energy of the emission.

Alpha decay via tunnelling was also solved concurrently by Ronald Gurney and Edward Condon. Shortly thereafter, both groups considered whether particles could also tunnel into the nucleus.

After attending a seminar by Gamow, Max Born recognized the generality of quantum-mechanical tunnelling. He realized that the tunnelling phenomenon was not restricted to nuclear physics, but was a general result of quantum mechanics that applies to many different systems. Today the theory of tunnelling is even applied to the early cosmology of the universe.

Quantum tunnelling was later applied to other situations, such as the cold emission of electrons, and perhaps most importantly semiconductor and superconductor physics. Phenomena such as field emission, important to flash memory, are explained by quantum tunnelling. Tunnelling is a source of major current leakage in Very-large-scale integration (VLSI) electronics, and results in the substantial power drain and heating effects that plague high-speed and mobile technology.

Another major application is in electron-tunnelling microscopes (see scanning tunnelling microscope) which can resolve objects that are too small to see using conventional microscopes. Electron tunnelling microscopes overcome the limiting effects of conventional microscopes (optical aberrations, wavelength limitations) by scanning the surface of an object with tunnelling electrons.

Quantum tunnelling has been shown to be a mechanism used by enzymes to enhance reaction rates. It has been demonstrated that enzymes use tunnelling to transfer both electrons and nuclei such as hydrogen and deuterium. It has even been shown, in the enzyme glucose oxidase, that oxygen nuclei can tunnel under physiological conditions

Monday, January 26, 2009

Line Follower ROBOT















This Robot use two motors control rear wheels and the single front wheel is free. It has 4-infrared sensors on the bottom for detect black tracking tape, when the sensors detected black color, output of comparator, LM324 is low logic and the other the output is high.
Microcontrollor AT89C2051 and H-Bridge driver L293D were used to control direction and speed of motor.



CIRCUIT DIAGRAM OF INFRARED SENSORS AND COMPARATORS




Position of sensors, left hand side is side view and right hand side is top view.
Software
Software for write to AT89C2051 is robot1.hex ,which was written by C-language ,the source code is robot1.ccompiled by using MC51 in TINY model with my start up code robot.asm .

NANOTECHNOLOGY improves battery life

Researchers at the Shenyang National Laboratory for Materials Science in China have been investigating how to improve the kind of rechargeable batteries that are used in mobile phones, MP3 players, personal digital assistants and laptop computers.

They found that after 20 cycles of the semi-cell experiments, the sugar-coated Si-CNT composite material achieved a discharge capacity of 727 mAh per g. In contrast, the charge capacity of the simple sugar-coated particles had dropped to 363 mAh per g.

Hui-Ming Cheng and colleagues have turned to carbon nanotubes (CNTs) to help them use silicon (Si) as the battery anode but avoid the material's usual problem of large volume change during alloying and de-alloying that can lead to faster capacity loss.

Li-Ion batteries suffer from degradation, especially when they get too hot or too cold, and eventually lose the capacity to be fully recharged. The problem of the slow degradation of Li-Ion batteries is usually due to the formation of a solid electrolyte interphase film that increases the batteries' internal resistance and prevents a full recharge.

The researchers grew carbon nanotubes on the surface of tiny particles of silicon using a technique known as chemical vapour deposition, in which a carbon-containing vapour decomposes and then condenses on the surface of the silicon particles forming the nanoscopic tubes.

They then coated these particles with carbon released from sugar at a high temperature in a vacuum. A separate batch of silicon particles produced using sugar but without the CNTs was also prepared.

With the Si-CNT anode material to hand, the team then investigated how well it functioned in a prototype Li-Ion battery and compared the results with the material formed from sugar-coated silicon particles.

The growth of carbon nanotubes on silicon suppresses the structure destruction of the composite during charge cycling, resulting in the improvement of cyclability, according to the researchers.

Researchers demonstrate ‘AVALANCHE EFFECT’ in solar cells



Proof that the ‘avalanche effect’ by electrons occurs in specific, very small semi conducting crystals could pave the way for cheap high-output solar cells.

Researchers at TU Delft and the FOM Foundation for Fundamental Research on Matter have discovered this phenomenon.

Solar cells provide opportunities for future large-scale electricity generation. However, there are currently significant limitations, such as the relatively low output of most solar cells (typically 15%) and high manufacturing costs.

One possible improvement could develop from a solar cell made of semiconducting nanocrystals which could lead to theoretical maximum output of 44%.

In conventional solar cells, one photon can release precisely one electron. The creation of these free electrons ensures that the solar cell works and can provide power.

The more electrons released, the higher the output of the solar cell.

In some semiconducting nanocrystals, however, one photon can release two or three electrons, hence the term 'avalanche effect'.

The avalanche effect was first measured by researchers at the Los Alamos National Laboratories in 2004. Since then, the scientific world has raised doubts about the value of these measurements. Does the avalanche effect really exist or not?

Within the Joint Solar Programme TU Delft’s Prof Laurens Siebbeles has now demonstrated that the avalanche effect does indeed occur in lead selenide (PbSe) nanocrystals.

It has been established, however, that the effect in this material is smaller than previously assumed. Siebbeles claims his results are more reliable than those of other scientists due to more careful and more detailed measurement using ultra-fast laser methods.

Siebbeles believes that this research paves the way for further unravelling the secrets of the avalanche effect.

Tuesday, December 23, 2008

INTEGRATED CIRCUITS




The first integrated circuit

In electronics the integrated circuits( also known as IC microcircuit,microchip etc.,) is a miniaturized circuit(consists of mainly semiconductor devices and also passive elements) that have been manufactured in the surface of thin substrate of semiconductor material. Now a days the integrated circuit devices are use all electronic devices like computer mobiles etc.There are many generations of this circuit. This was first invented by Jack kilby

for more information on generation refer the magazine