D라이브러리

매년 15%이상 성장하고 있다. 삼성전자는 레이저다이오드외에 LED(발광다이오드, Light Emitting Diode)의 상품화도 추진하고 있으며 앞으로 고속소자분야에도 진출할 계획이다 ...

(tubes from which all the air has been removed, creating a vacuum) at right angles. In each tube, a beam of laser light would be reflected back and forth a thousand times or so. If the tubes are comletely undisturbed, the light-wave will remain in perfect step.If a gravitational wave sweeps over the tubes, however, one tube would be compressed a very tiny bit more than the other, and that ...

세기가 약해진다. 이때 광섬유 전송선로에 레이저광(LD, Laser Diode)이나 발광다이오드(LED, Light Emitting Diode)로부터 나온 빛을 더해준다. 네오디뮴원자는 이 빛을 받아 광통신에 적합한 1.3μ(1μ은 ${10}^{-6}$m)대 파장의 빛만 정보를 실은 빛에 더해준다. 1.3μ은 현재 광통신시스팀에 가장 많이 활용되고 있는 ...

light waves then tended to skip over them so the objects could not be seen.To get around this, you might use shorter light waves such as ultraviolet. For a while, therefore, scientists used "ultra-microscopes," but these represented only a small improvement. Still shorter waves could not be focused properly.But then, in 1923, a French scientist, Louis de Broglie, pointed out that subatomic ...

everywhere on Earth.It may well be possible, however, to measure the slight changes in the shape of the Earth and the slight movements of its surface from satellites-a kind of "global geodesy" made possible by the view from space. We could get a general picture of the motions of all the plates, the building up of strains everywhere. A computerized analysis may tell us just when the strains ...

probably see many more of them.Why is that important? Because we see galaxies that are 17 billion light-years away by light that took 17 billion years to reach us. We see these galaxies as they were in the early youth of the universe. They can tell us about the manner in which galaxies formed all that long time ago. That is something that astronomers would dearly love to know more about, and ...

just like a resinous torch. This apparently must have been what the primitive inhabitants did-used bonetorches to light their way in the caves, and to keep things warmer when it was cold.Those burnt bones are up to 1,500,000years old, three times as old as the campfires of Zhoukoudian. There were no signs of charred bones buried in older layers in the caves, but once they began to appear, ...

hand, no way of making the burning of coal and oil safe.The best source of energy, of course, would be solar energy. Light and heat from the sun reaches Earth anyway, and if we use that heat before it is absorbed by Earth's surface, that would in no way increase the heat content of Earth or change the atmosphere.Working form the other end, how can we remove the carbon dioxide once it is in the ...

much dust thrown up into the upper atmosphere by the strike, and smoke from the forest fires as well, that the sun's light would have been prevented from reaching the Earth's surface for a period of time. The cold and dark that would then have prevailed would have killed most of Earth's vegetation and the animals that depended upon it.Then, beginning in 1982, some people began to wonder ...