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Words, grammatical forms and meanings linked to the ontology.

neper en · NOUN

Etymology

From Joannes Neper, the Latinized name of John Napier, a Scottish mathematician.

Meanings

  1. A non-SI unit of the attenuation (or sometimes gain) of field and power quantities such as electronic signals; the natural logarithm of a ratio, with 1 Np (a ratio of 2.718:1) being equivalent to 8.686 dB.
    • The attenuation constant for the phantom muscle tissue is αₘ = 10.0 nepers/m. 2008, Alan J. Fenn, Adaptive Phased Array Thermotherapy for Cancer, page 105:
    • Values of b, the amplitude attenuation constant, are given for various materials in Table 1.1. Having dimensions of [length]⁻¹, it is usually measured in nepers per centimetre (Np cm⁻¹). 1994, T. G. Leighton, The Acoustic Bubble, page 28:
    • The unit of α is nepers per meter. It can be easily seen that if a line has an attenuation constant of 1 neper/m, a unit amplitude voltage wave will reduce to e⁻¹ over a distance of 1 meter. 2006, R. K. Shevgaonkar, Electromagnetic Waves, page 15:

Forms

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nepers Number=Plur lexicographic

Relateds

Np

wikipedia: John Napier