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Electrical damage
by E-bombs
THIS UNIVERSE |
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Electrical damage
by E-bombs The E-bomb technology was first observed during the testing of high altitude nuclear weapons. This works on the principle of electromagnetic pulse (EMP) effect produced during the nuclear explosion. It gives rise to a very short but intensive electromagnetic pulse. The EMP effect is simply an electromagnetic shock wave, which generates a powerful electromagnetic (e.m.) field in the surroundings of the weapon burst. The field can generate a transient voltage of thousands of volts on the exposed electrical wires and conductive tracks on the printed circuit boards. This can cause an irreversible damage to a wide range of electrical and electronic equipment viz transformers, generators, computers, radio and radar systems etc. The main devices used for producing such fields are flux compression generators (FCG) and a range of high power microwaves (HPMs). The FCG can produce electrical pulses of energy of 10 MJ to 100 MJ in a time period of hundred of microseconds. The maximum power delivered which is of order of tens of tera watts, can produce currents upto 1000 times greater than in a typical lightning stroke.
Lethality For a given radius and device design, the strength of electromagnetic field will determine the killing probability for a specific class of target. The lethality of E-bombs depends upon (i) electromagnetic hardness of the target and (ii) coupling efficiency. The latter is the measure of power transferred from the field into the target. When the energy from the field is coupled into the equipment through its antenna, it is termed as front door coupling. In the devices with no antenna, the coupling is achieved through the backdoor process in which the field induces large transient current on fixed electrical wires and cables. These transient currents will damage the power supplies of electrical equipment.
Targeting Like conventional bombs, the targeting of E-bombs firstly requires the ready identification of the targets. This can be done by conventional methods like satellites, radar and electronic reconnaissance operation. The E-bomb is basically an electromagnetic device with electrical energy converter and an energy storage device to pump and sustain the charge on the device after its delivery from the platform. These bombs, on dropping, are ignited by a fusing system either on board or from remote. The onboard system makes the bombs heavier resulting into less warhead operation mass (WOM). Therefore, the ignition is generally executed by the remote system that allows greater WOM. The US fighter planes F-117A and B-2A are capable of delivering such bombs. While dropping such bombs, important point is that the bomber must be allowed to gain sufficient distance
(several miles) from the warhead detonation otherwise the electronic system of the aircraft would get spoiled. To get greater lethality, the E-bomb should offer a better ratio of e.m. device mass to the total bomb mass. To every technology, there is a method to counter it. The most effective protection from E-bombs is firstly to destroy them before their delivery. If it is not achieved, then, the electronic devices must be electromagnetically hardened. This is done by housing the equipment in an electrically conducting chamber, called Faraday cage. This cage prevents the e.m. field from entering into the protected equipment. As the input and out leads of equipment are prone to the e.m. fields, these leads must be fitted with e.m. arresting devices. The communication networks should employ topologies with many redundancies and failure mechanisms to allow the operation with many multiple nodes and links inoperative. This will not allow the E-bomb user to disable the large portion of the network by taking down one or more key nodes with a single attack. Thus, the E-bombs can serve as an affordable force multiplier for military forces to reduce forces size and increasing combat potentials. Those who choose not to use such bombs may become losers in the future wars. |
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Saraswati’s route
The Oil and Natural Gas Commission (ONGC) will look for the long-lost Saraswati river in the desert of Rajasthan. The project, named Saraswati, started off on Tuesday with the digging of well in Jaisalmer’s Dabla sector. A number of deep wells have been dug under the project. The ONGC, till now involved in drilling oil wells, has now taken up the project for the first time to find the route of the now dried up Saraswati river.
— UNI
Making Tamiflu cheap
From late 2005 the threat of a flu pandemic has massively increased demand for oseltamivir - better known by its trade name Tamiflu. Now manufacturer Roche has joined forces with other companies to boost production, and generic drug makers have started producing their own versions. So supplies of the drug look set to meet or even outstrip demand by 2007. But significant questions remain - such as the treatment’s affordability to poorer nations and its efficacy against the H5N1 bird flu virus. While generic versions currently cost as much as Tamiflu, competition will probably drive prices down. More promising news for developing countries, perhaps, is the work of researchers at Harvard University in the United States, who have devised a cheaper way to make the drug.
SciDev.Net
N-science for development
As tensions mount over Iran’s nuclear standoff, the risks of radiation-based technologies are surging back into the headlines and onto public agendas. At the centre of the fray, one UN agency carries the unenviable responsibility of regulating one of modern science’s most controversial advances. The UN’s International Atomic Energy Agency (IAEA) is best known as the world’s nuclear watchdog; an intergovernmental body that argues against the proliferation of nuclear weapons, and sets international standards for the safety and security of radiation sources.
SciDev.Net
Psoriasis breakthrough
The dream of the dermatologists to surmount the serious reactive effects in patients associated with a very popular anti-psoriatic drug, Dithranol, has now become a reality at University Institute of Pharmaceutical Sciences (UIPS) of Panjab University. A team of scientists and researchers led by Prof O.P. Katare, currently the Chairman of the Institute, has reached a landmark success in the discovery of a novel drug delivery product.
— UNI |
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THIS UNIVERSE Kindly tell me why mosquitoes bite one individual and not another. I was travelling in a train with my sister. We were sleeping in the same compartment. While mosquitoes neglected me completely my sister was bitten endlessly. We eat the same kind of food and neither of us wears scented products. Your question correctly implies that mosquitoes seek their prey through their sense of smell. It is amazing that a tiny little creature should have developed a capability of such discrimination. I have read that different species of mosquitoes may have slightly different tastes also implying different capability of smell differentiation. From what I have read the picture looks somewhat like this: The first sensing probably occurs through increase of carbon dioxide in some surrounding. That is a signal that there is living breathing thing that might provide a tasty meal. More sophisticated smelling capabilities then take over. Our perspiration does not smell exactly same for all of us. Our skins exude chemicals that have a slightly different combination. Some of the combinations have an attraction for mosquitoes others do not. Some smells are definitely revolting to them. Others confuse them by overwhelming what they are looking for. If we rub some plant leaves on our skins mosquitoes might leave us alone thinking we are plants. Citronella probably works because of this. They are also driven out of a room where a “havan” has been performed or “agarbattis” have been lighted. Heavy additional smells confuse the mosquitoes. Some people say that mosquitoes leave garlic eaters alone — I am not sure if it is true. Some scientists are working to identify dozens of chemical odours from our skin that are attractive to mosquitoes and others that are not. Perfect mosquito repellents are yet to be found. Why don’t you do an experiment? Let your sister include lot of garlic in her diet for a few weeks and then see if she becomes as protected from mosquitoes as you are! I do not imply, of course, that you are an enthusiastic garlic eater. Everyone has a right to discover his personal protector.
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Till date, the air power had been the most effective means of crushing the opponent’s information processing and transmission systems. This has already been displayed in Desert Storm operation unleashed by US forces in Iraq war. But it has played havoc with the life of human beings and resulted in immense loss to property. The development of electromagnetic bombs (E-bombs) has proved a very effective tool for electrical damage to the strategic targets sans loss to human life.