propagation+by+layers
21Earth 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… …
22Underwater acoustics — The field of underwater acoustics is closely related to a number of other fields of acoustic study, including sonar, transduction, acoustic signal processing, acoustical oceanography, bioacoustics, and physical acoustics.HistoryUnderwater sound… …
23Laser diode — Top: a packaged laser diode shown with a penny for scale. Bottom: the laser diode chip is removed from the above package and placed on the eye of a needle for scale …
24cosmos — /koz meuhs, mohs/, n., pl. cosmos, cosmoses for 2, 4. 1. the world or universe regarded as an orderly, harmonious system. 2. a complete, orderly, harmonious system. 3. order; harmony. 4. any composite plant of the genus Cosmos, of tropical… …
25light — light1 lightful, adj. lightfully, adv. /luyt/, n., adj., lighter, lightest, v., lighted or lit, lighting. n. 1. something that makes things visible or affords illumination: All colors depend on light. 2. Physics …
26thunderstorm — /thun deuhr stawrm /, n. a transient storm of lightning and thunder, usually with rain and gusty winds, sometimes with hail or snow, produced by cumulonimbus clouds. Also called electrical storm. [1645 55; THUNDER + STORM] * * * Violent, short… …
27horticulture — horticultural, adj. horticulturist, n. /hawr ti kul cheuhr/, n. 1. the cultivation of a garden, orchard, or nursery; the cultivation of flowers, fruits, vegetables, or ornamental plants. 2. the science and art of cultivating such plants. [1670… …
28Coaxial cable — RG 59 flexible coaxial cable composed of: A: outer plastic sheath B: woven copper shield C: inner dielectric insulator D: copper core Coaxial cable, or coax, has an inner conductor surrounded by a flexible, tubular insulating layer, surrounded by …
29Medium frequency — Frequency range 0.3 to 3 MHz ITU Radio Band Numbers 1 2 3 4 5 6 7 8 9 10 …
30Superlens — 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,… …
