Demolition technology
by Jagvir Goyal
DEMOLITION is one area India has never bothered to concentrate upon. Ours being a developing country, emphasis has rather been on development. We develop cold feet when it comes to demolishing some structure. There exist innumerable old and unsafe buildings; narrow, half-a-lane bridges that need to be demolished to give way to new multistoreyed buildings; wide and safe flyovers.

New virus arrives as Y2K bug fixer
A new computer virus disguised as Y2K bug fixer, “W95.Babylonia”, which infects the Windows platforms, is invading number of computers connected to the Internet.

Science Quiz
by J. P. Garg

A matter of antimatter
by R.C. Verma and B.R. Sood

IN the beginning, just after the Big Bang announced the birth of our universe, there was plenty of pure energy packed densely in an extremely small primordial fireball. With the big bang were created space and time. Before the clock could tick even the first second the bundle of energy that the universe was underwent many transformations.

It was an action-filled first moment in the real sense of the word. One of the transformations to occur was the creation of material particles out of pristine energy while universe expanded at a fast rate. To be precise energy converted itself into pairs of a particle and its counterpart, an antiparticle. The fundamental particles thus created combined together in various combinations to yield composite particles like a proton, a neutron and plethora of others. Pairs of particles and antiparticles also annihilated each other giving back energy.

This process was over within one second and left behind a small number of material particles. Congregation of particles (both fundamental and composite) and resulting atoms manifested itself in the form of matter. This process dominated for first 10,000 years. The material world of today in the form of innumerable galaxies (created in one to two billion years) is the consequence of coming together of the fundamental and composite particles and their aggregates (nuclei and atoms). In a similar fashion an assembly of antiparticles would lead to antimatter forming anti-galaxies. If such objects exist,however, they must be rare.

It is an established fact that the amount of matter in our universe far exceeds that of antimatter although particles and antiparticles were originally created in equal numbers. It is estimated that for every one lakh kilograms of matter there is only one gram of antimatter. Speculation of the anti-galaxies made purely of antimatter has not been verified within our universe so far.

Scientific history of antiparticles (and of antimatter) started in 1928 when Nobel laureate physicist P.A.M. Dirac predicted on a theoretical basis the existence of a particle that, in certain respects, was similar and in others in contrast with an electron. This particle was observed experimentally in 1932 and was christened positron. A positron, it turned out later, is an antiparticle of the electron. It has the mass equal to that of the electron but opposite charge. There has been no looking back on the story of antiparticles since then.

Later, a basic theorem in physics enunciated that “for every particle that exists in nature there is a corresponding antiparticle”. This theorem further states that the antiparticle has the same mass as its particle, the same lifetime (if the particle is not stable), the opposite charge and the opposite of all other parameters that are called quantum numbers. So far this theorem has been found to hold good universally.

As stated earlier, a pair of a particle and its antiparticle can be created starting from energy. Reverse of this process is also possible. A particle and its own antiparticle upon coming in contact with each other annihilate themselves yielding energy. Phenomena of pair production and particle-antiparticle annihilation prove conclusively the equivalence and mutual convertibility of mass and energy.

Incidentally,this equivalence has been predicted by Albert Einstein much earlier. Antiparticles of various fundamental particles, such as electron, quarks, and neutrinos, have been observed experimentally. also antiparticles of composite particles like proton, neutron and a variety of others in this category have also been observed. Then there are instances in radioactive substances were antiparticle,like positron or antineutrino, is emitted by the nucleus made up of matter.

In recent years researchers have attempted to produce atoms (a better term is antiatoms) made from only antiparticles. Simple antiatom should be antihydrogen formed by a positron orbiting around an antiproton. Antihydrogen production is within the realm of the possible and studies carried on this simple form of antimatter should throw light on the basic principles of physics and of cosmology.

One point that needs elaboration is the preponderance of matter over antimatter in our universe. To start with particles and antiparticles were created in equal numbers from energy. Later on the pairs of particle and its antiparticle annihilated. The residue of excess matter left behind constitutes our universe. Possibly some regions of antimatter may exist somewhere, there is a consensus that the universe is mainly matter dominated. The belief is strengthened by the absence of any known mechanism that could have separated the matter from antimatter over large distances in the universe. The basic puzzle is how this excess of matter was generated. Modern theories of fundamental forces of nature predict the existence of new mechanisms which can provide a plausible answer to this puzzle. These theories speculate that superheavy particles were created soon after the big bang. As the universe expanded and cooled down, the superheavy particles decayed asymmetrically producing slightly more particles than antiparticles. This favourable tilt towards the production of particles is responsible for excess of matter. Experimental testing of these theories is going on in various laboratories all over the world.

The writers from the Department of Physics, Punjabi University, Patiala.

Demolition technology
by Jagvir Goyal

DEMOLITION is one area India has never bothered to concentrate upon. Ours being a developing country, emphasis has rather been on development. We develop cold feet when it comes to demolishing some structure. There exist innumerable old and unsafe buildings; narrow, half-a-lane bridges that need to be demolished to give way to new multistoreyed buildings; wide and safe flyovers. Traffic is increasing day by day and business is on the rise thus demanding more and more buildings, offices, commercial buildings, dwelling units and a well-connected and capable road-transport-network. All this is possible only if the old and outlived structures are removed and land is freed for the new ones to come up.

In India, demolition is avoided as if it is something inauspicious, involving wasteful expenditure. Another factor is our crude method of demolition. If we are asked to demolish an old bridge or a building, we put a large labour force armed with chisels and hammers on it. Otherwise we try to ram a bull-dozer into the structure. At the most we deploy some pneumatic jack-hammers to dismantle the RCC or brick-work. There exit no planned methods to execute “demolition”.

Now is the time that India develops demolition technology suitable to Indian conditions. For this, the structures are to be categorised and requirements are to be defined. A blind adoption of the techniques being used in foreign countries may not be conducive to Indian layout.

Indian structures

On a broader scale and from demolition point of view, the Indian structures can be divided into following categories:

1. Tall chimneys of power plants and large sized natural draught cooling towers.

2. Multistoreyed buildings.

3. Heavily reinforced bridges and buildings.

4. Ordinary buildings, houses, brick-structures etc.

Requirements

Thinking of the requirements that the demolition technology should fulfil, the following shall form an ideal list:

1. Quicker demolition.

2. Quieter demolition.

3. Cheaper demolition.

4. Environment-friendly demolition.

5. Demolition causing least disturbance in the neighbourhood.

Therefore, whenever a structure is to be demolished, it must be seen that the method adopted is such that it takes minimum time, produces least level noise, causes no pollution beyond permissible limits, does not disturb the activity or living in the neighbourhood and proves cheaper also. In foreign countries, regulations exist to control dust and noise pollution during demolition. Such regulations can be devised for our country also even though most of the demolitions will fall within the ambit of government departments only.

Physical survey

It is essential to survey the surroundings of the structure to be demolished. The surroundings will decide whether a structure is to be toppled or made to collapse or shattered or imploded or exploded. The position of the water-supply lines, telephone cables and electricity wires is also to be checked. It has to be ensured that the supplies to the adjacent buildings are not disturbed. Whenever explosion-demolition technology is to be used, it is to be seen that the computers and the equipment installed in the nearby buildings are not affected by the vibrations produced by the explosions. If a demolition involves rise of clouds of dust, the ducts of AC systems in the adjacent buildings are to be sealed against entry of dust in them. Overall approach has to be cause least disturbance to the surroundings.

The construction drawings of the structure to be dismantled will not be available as it may be over 40 to 50 years since the time that structure was built. Therefore core tests may be done to have an idea of the concrete strength or density of reinforcement. The position of the expansion joints in the building should also be assessed as it will help in planning the demolition of the building.

Technology abroad

Explosive demolition technology has become most popular in foreign countries. High-rise chimneys and massive cooling towers are made to collapse through telescopic technique by placing explosives in such a manner that an almost vertical collapse occurs. Under this technique, large compressive stresses are produced at the base of the structure and it descends in a continuous manner like a house of cards. While the explosives cause the initial collapse, further fragmentation is caused by gravity only. Often such demolitions provide a spectacular show making people wonder at the advance of technology. Technically, this is just a game of following a laid set of guidelines and an expert supervision.

Wherever environmental regulations impose restrictions over use of explosives, chemical techniques are being applied. These techniques also are highly effective. Alloy steel cartridges filled with liquid carbon dioxide and some chemical igniting agent are fixed in position and then detonated from a safe distance. Expanding carbon dioxide gas breaks up steel cartridge and attacks the surrounding material with a cold heaving force. This technique is capable of breaking very hard materials.

Water bursting and water jetting are other techniques being used. Special methods are being devised to dismantle pre-stressed concrete and post-tensioned concrete structures.

Lessons for India

Indian conditions are not fully ripe to adopt explosive demolition technology. Dense population, haphazard growth, non-existence of any byelaws or regulations and our casual approach makes use of explosives a risky affair for us. The complex and dangerous business of use of explosives needs a very strict set of guidelines to be followed in an explicit manner, an expert supervision and a comprehensive planning exercise to determine the sequence of removal of components of the structure and the placement of the charges. Minutest details are to be worked out. For example, the rough end of a steel bar exposed while making holes can cut the detonating cord or detonator lead wires. A record of the vibrations and airblasts produced has to be kept and instruments capable of making these measurements should be installed. Private companies who promise to develop foolproof methodology for explosive demolition should be extended full cooperation and assistance by the Government.

Hydro-demolition is another area India should concentrate upon. Heavyduty hydraulic hammers of 30 to 50 tonne class develop by Krupp industries can operate at 250 to 450 blows per minute and can work underwater also. Other leading companies of the world such as Labounty of USA whose universal processor can rotate at 360 degrees and can demolish concrete as well as steel by fixing alternative jaws, Brokk of Sweden, which is known for noiseless concrete demolition, Conjet of Sweden that can cut concrete and asphalt by water-jet system at twice the speed of sound, NPK of Japan that provides world class hydraulic rammers and Atlas Copco of Sweden which is a master of rock-drilling technology should be allured to collaborate with Indian firms till the time a switch-over of technology takes place.

While the telescopic collapse triggered by explosion technology is most suitable for tall chimneys and cooling towers, hydro-demolition suits multistoreyed buildings and the densely reinforced concrete structures. Ordinary buildings, houses and brick-structures can be demolished by hydraulic hammers, jack rammers, impact breakers or ordinary splitters. Final choice of the technique to be adopted however, depends upon the actual site conditions.

Day by day, redevelopment of walled cities, better utilisation of land and rapid industrial advancement is demanding for development of cost-effective, environment-friendly, quick and quiet demolition technology. It is time we too this aspect too within our stride during our relentless march for progress.

New virus arrives as Y2K bug fixer

A new computer virus disguised as Y2K bug fixer, “W95.Babylonia”, which infects the Windows platforms, is invading number of computers connected to the Internet.

“W95.Babylonia” is the first of a new class of virus that is automatically downloading new components via the Internet, two IT majors Computer Associates and Network Associates said in their press releases.

The new virus infects Windows platform and will attempt to infect every executable and help file in the users Windows environment.

Babylonia is currently disguised as a Y2K Bug fix for Internet Relay Chat (MIRC) users, the largest and well known online chat communities in the world.

Babylonia automatically sends itself to MIRC users and begins polling a hacker’s Internet website every 60 seconds looking for new “plug-ins”.

Some potential damaging plug-ins that the virus author could send remotely are formatting or deleting a user’s hard drive, collecting and sending sensitive credit card information or installing a Y2K specific attack.

This is the first time a virus has the capability of altering its instructions from the virus author remotely and on demand.

CA said users can protect their information by downloading antivirus solution from www.cai.com or www.antivirus.cai.com.

Network Associates said consumers can protect their information by downloading antivirus software from www.nai.com or www.McAfee.com

Babylonia is a complex 32 bit worm distributed via Internet Relay Chat virtual meeting channel, the most popular chat application for the Windows operating system. (TNS)

Science Quiz
by J. P. Garg

1. Name the Indian scientist, known as the father of Green Revolution in India, who was recently conferred with the “Scientist Century” award for developing some high-yielding crops and introducing new methods to increase agricultural production.

2. EDSAC and EDVAC are two terms connected with computers. What do these stand for?

3. The disorder in all the physical systems in the universe is continuously increasing. What name is given to this chaos in science, wherein it expresses the degree to which heat energy can be converted into work. To which particular branch of science is this study related?

4. Out of eight different species of tigers in the world found earlier, three have been declared extinct recently. Can you name these? What for are the tiger bones generally used, that has led to the fast extinction of these species?

5. In old age, the density of bones decreases, the bones become porous and brittle and even a stumble may lead to bone fracture. What is this condition called? Which two main nutrients are required to prevent this disease?

6. Ethanedioic acid is a poisonous, colourless, crystalline organic acid whose salts occur naturally in some plants. It is used for cleaning of metals and textile, and in tanning. What is the popular name of this acid?

7. What is the device called by which an exact copy of written text, figures, photographs etc. can be produced by electronic scanning and also transmitted and received via a telephone system?

8. Environmentalists are worried that this bird may soon become extinct due to its rapidly depleting numbers. A few of these birds were recently spotted in Punjab. Can you name this scavenger bird, which has a very efficient digestive system and generally feeds on carcasses?

9. Which is the farthest object that can be seen with the naked eye? What is its distance from the earth?

10. This spacecraft was designed to act as the first robot that could record sounds on other planets and sends these to earth. But NASA scientists have not been able to establish contact with it despite their recent repeated attempts. Name this spacecraft.

Answers

1. M.S. Swaminathan 2. Electronic Delay Storage Automatic Computer and Electronic Discrete Variable Automatic Computer 3. Entropy; thermodynamics 4. The Bali, the Java and the Caspain tiger; for making rare medicines 5. Osteoporosis; calcium and vitamin D 6. Oxalic acid 7. Fax (Facsimile) 8. Vulture 9. Andromeda Galaxy; 2.2 million light-years (one light-year is 9.5x1012 km) 10. Mars Polar Lander.

Gray Cell’s instant messaging
GRAY Cell has released the beta version of an integrated instant messaging, email management and Internet services tool delivered via mobile devices and desktop PC.

Code-named Unimobile, the first ever Internet consumer product from India, is a desktop software that enables users of mobile devises and PCs to send instant messages, select personal email delivery options and receive customised Internet services — all on a single interface on the desktop, mobile device or both.

The beta preview version of Unimobile is currently available for free download at www.unimobile.com. The product is scheduled for full-feature release in first quarter of 2000.

Cisco wireless Internet
CISCO Systems Inc., the worldwide leader in networking for the Internet has announced that it is joining forces with 10 leading companies to drive open standards for broadband wireless Internet services.

At the core of this coalition is a new technology that delivers two-way data, voice and video communications over the air to both home and business, enabling high speed services comparable to today’s most advanced cable networks.

The new wireless technology works well in congested cities, suburban and rural environments by overcoming the line-of-sight, distance reach, subscriber coverage, installation, and antenna size problems of existing proprietary wireless systems mainly in lower frequency microwave bands.

TrueNet for better efficiency
KRONE Communications and Prestolite Wire Corporation have jointly launched TrueNet, the world’s first cabling system to effectively prevent throughout loss in local area networks. TrueNet is tuned to protect the total efficiency of the network.

TrueNet goes beyond ensuring category 5, 5e or 6 compliance. The structured cabling comes with a revolutionary warranty, offering a five year throughout warranty guaranteeing zero bit error rate performance over and above the 20-year all inclusive industry standards compliance guarantee.

Many companies have undiagnosed problems where mismatched components cause impedance in their Ethernet cabling systems. These problems can diminish network performance without the users ever realising that it is the cabling system that is causing data errors and slowing down throughout.

Dell launches new notebook PCs
DELL Computer Corporation, the world’s leading direct computer systems company, has announced two new latitude, C-family corporate notebook PCs with faster processor, dual-pointing options and enhanced graphics capabilities that offer customers a range of performance and value options. Dell also introduced a new CD-Read/Write module for all latitude C-family notebooks.

The Latitude CPx H500GT features the latest Intel Mobile Pentium III processor at 500 Mhz. The Latitude CPx also features the new Dell Dual Point design that integrates two cursor pointing devices — a touch pad and a pointing stick. Designed to improve usability, DualPoint lets customers use either device or both.

The notebook comes with 8 MB of video RAM and 2X AGP support for smooth video performance on its 14.1 inch TFT display. It also supports up to 512 MB RAM, one of the largest capacities in the industry.

Dell also announced a new addition to its CPt line that is targeted to price-sensitive institutional customers such as government and education. Like the high performance CPx, the CPt offers the Dell DualPoint device and 8 MB of Video memory.

The company also introduced new computer systems with the fastest Intel Pentium ITI processors based on the 0.18 micron process manufacturing technology, advanced transfer cache with advanced system buffering capabilities, thus providing significant performance enhancements over processors of the same clock speed with older technology.

Cognos launches visualizer
COGNOS has launched visualizer in India, which is a business management and measurement solution that leverages human visual perception enabling users to see large amount of date with multiple date dimensions or data with a strong geographical element which turns data into tangible infomation.

Fully integrated with Cognos enterprise reporting and online analytical processing solutions, Cognos visualizer lets users quickly and intuitively gain insight to scorecard their business activities and make better decisions.

Cognos visualizer has a range of business applications and is ideally suited to scorecard- style solutions because the intuitive nature of visualisations allow decision makers to quickly understand a large number of measures, data relationships and trends that characterise their business. Large amount of data from one or many sources may be combined into succinct visual reports and virtual rooms of information. Through custom-designed or wizaed-driven templates, users may tailor their reports, place data into maps, apply filters, create animations and set multiple views of their 2D or 3D visualisations.

First CCIE test lab in India
Cisco Systems has started its first Cisco Certified Internetwork Expert (CCIE) test lab in Bangalore. Equipped with state-of-the-art technologies, the lab will provide the CCIE hands-on testing leading to certification for networking professionals in the area of routing and switching.

The CCIE programme which is the industry’s most respected net working certification vehicle, sets the professional benchmark for internet working expertise, providing knowledge of established and newer technologies. Three areas of certification offered are routing and switching. WAN switching and ISP-Dial. SNA/IP integration will also be introduced soon.

IDT FIFO memories
Integrated device technologies (IDT), the industry’s leading supplier of first-in first-out (FIFO) memories, has launched a new family of 4 Mbit 36-bit by -directional FIFI memories.

IDT has achieved the industry’s highest density,and increasing the clock speed of existing members of the FIFI family to 100 MHz.

The company has also increased the speed of its 3.3-volt 36-bit synchronous dual-port memory devices to 133 MHz creating the industry’s fastest 36-bit dual port family.

The FIFO are optimised for high-performance systems with speed and densities,that enable the extremely high data throughout and high bandwidth required by LANs. WANs and storage area networks(SANs), all of which are used to transfer and process information over the Internet as well as data and computation-intensive applications.