relative field pattern
21Superlens — A superlens, super lens or perfect lens is a lens which uses metamaterials to go beyond the diffraction limit. The diffraction limit is an inherent limitation in conventional optical devices or lenses.[1] In 2000, a type of lens was proposed,… …
22Fraunhofer diffraction — In optics, Fraunhofer diffraction is a form of wave diffraction, which occurs when field waves are passed through an aperture or slit, causing only the size of an observed aperture image to change Hecht, E. (1987) , p396 Definition of Fraunhofer… …
23Induction motor — An induction motor (IM) is a type of asynchronous AC motor where power is supplied to the rotating device by means of electromagnetic induction. Other commonly used name is squirrel cage motor due to the fact that the rotor bars with short… …
24Negative index metamaterials — A negative index metamaterial causes light to refract, or bend, differently than in more common positive refractive index materials. Negative index metamaterials or negative index materials (NIM) are artificial structures where the refractive… …
25Induction heating — is the process of heating an electrically conducting object (usually a metal) by electromagnetic induction, where eddy currents are generated within the metal and resistance leads to Joule heating of the metal. An induction heater (for any… …
26Effective mode volume — For an optical fiber, the effective mode volume is the square of the product of the diameter of the near field pattern and the sine of the radiation angle of the far field pattern. The diameter of the near field radiation pattern is defined here… …
27Vertical plane — is used in radio to plot an antenna s relative field strength perpendicular to the ground (which directly affects a station s coverage area) on a polar graph. Normally the maximum of 1.000 or 0 dB is at the side (unless there is beam tilt), which …
28defense economics — Field of national economic management concerned with peacetime and wartime military expenditures. It arose in response to the greater scale and sophistication of warfare in the 20th century. Most nations seek to avoid the vast financial and human …
29Earth Sciences — ▪ 2009 Introduction Geology and Geochemistry The theme of the 33rd International Geological Congress, which was held in Norway in August 2008, was “Earth System Science: Foundation for Sustainable Development.” It was attended by nearly… …
30Life Sciences — ▪ 2009 Introduction Zoology In 2008 several zoological studies provided new insights into how species life history traits (such as the timing of reproduction or the length of life of adult individuals) are derived in part as responses to… …
