Friday, September 12, 2008

SLAX - OS in the pocket

I installed slax to my pen drive yesterday. it's a smart and a beautiful OS. and it also have a good booting speed. But the sad thing is there are no much modules which are compatible to slax. i downloaded many but some are not working.
Try it, it is a good OS...

Go to Slax official site >>
Some more KDE apps >>




Monday, August 11, 2008

Invisibility cloak one step closer, scientists say

I jst saw this on web.

By Maggie Fox, Health and Science Editor

WASHINGTON (Reuters) - Scientists have created two new types of materials that can bend light the wrong way, creating the first step toward an invisibility cloaking device.

One approach uses a type of fishnet of metal layers to reverse the direction of light, while another uses tiny silver wires, both at the nanoscale level.

Both are so-called metamaterials -- artificially engineered structures that have properties not seen in nature, such as negative refractive index.

The two teams were working separately under the direction of Xiang Zhang of the Nanoscale Science and Engineering Center at the University of California, Berkeley with U.S. government funding. One team reported its findings in the journal Science and the other in the journal Nature.

Each new material works to reverse light in limited wavelengths, so no one will be using them to hide buildings from satellites, said Jason Valentine, who worked on one of the projects.

"We are not actually cloaking anything," Valentine said in a telephone interview. "I don't think we have to worry about invisible people walking around any time soon. To be honest, we are just at the beginning of doing anything like that."

Valentine's team made a material that affects light near the visible spectrum, in a region used in fiber optics.

"In naturally occurring material, the index of refraction, a measure of how light bends in a medium, is positive," he said.

Read the full article >>>

Friday, August 1, 2008

Love

--
H.Madhawa Ranga
"No one knows what he can do till he tries."

Thursday, May 22, 2008

Sri Pada (Adam's Peak)

A photo of mount Sri Pada. (During out last trip)

"Saama Chaithyaya" ("Saama" dageba). You meet this when you are climbing Sri Pada.

Applications of superconductors

Superconducting magnets are some of the most powerful electromagnets known. They are used in MRI and NMR machines and the beam-steering magnets used in particle accelerators. They can also be used for magnetic separation, where weakly magnetic particles are extracted from a background of less or non-magnetic particles, as in the pigment industries.

Superconductors have also been used to make digital circuits (e.g. based on the Rapid Single Flux Quantum technology) and RF and microwave filters for mobile phone base stations.

Superconductors are used to build Josephson junctions which are the building blocks of SQUIDs (superconducting quantum interference devices), the most sensitive magnetometers known. Series of Josephson devices are used to define the SI volt. Depending on the particular mode of operation, a Josephson junction can be used as photon detector or as mixer. The large resistance change at the transition from the normal- to the superconducting state is used to build thermometers in cryogenic micro-calorimeter photon detectors.

Other early markets are arising where the relative efficiency, size and weight advantages of devices based on HTS outweigh the additional costs involved.

Promising future applications include high-performance transformers, power storage devices, electric power transmission, electric motors (e.g. for vehicle propulsion, as in vactrains or maglev trains), magnetic levitation devices, and Fault Current Limiters. However superconductivity is sensitive to moving magnetic fields so applications that use alternating current (e.g. transformers) will be more difficult to develop than those that rely upon direct current.