منابع مشابه
Logarithmic Fourier transformation
INTRODUCTION SUMMARY We present an exact and analytical expression for the Fourier transform of a function that has been sampled logarithmically. The procedure is significantly more efficient computationally than the fast Fourier transformation (FFT) for transforming functions or measured responses which decay slowly with increasing abscissa value. We illustrate the proposed method with an exam...
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Logarithmic transformation of the data has been recommended by the literature in the case of highly skewed distributions such as those commonly found in information science. The purpose of the transformation is to make the data conform to the lognormal law of error for inferential purposes. How does this transformation affect the analysis? We factor analyze and visualize the citation environmen...
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Department of Global Ecology, Carnegie Institution for Science, Stanford, CA 94305, USA Department of Natural Resources and Environmental Management, University of Hawai‘i at Mânoa, Honolulu, HI 96822, USA Institute of Pacific Islands Forestry, USDA Forest Service, Hilo, HI 96720, USA Department of Biological Sciences, University of Wisconsin-Milwaukee, Milwaukee, WI 53211, USA Smithsonian Trop...
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The application of logarithmic transformations to speckle images is sometimes desirable in converting the speckle noise distribution into an additive, constant-variance noise distribution. The optical transmission properties of some bacteriorhodopsin films are well suited to implement such a transformation optically in a parallel fashion. I present experimental results of the optical conversion...
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The membrane potential, arising from uneven distribution of ions across cell membranes containing selectively permeable ion channels, is of fundamental importance to cell signaling. The necessity of maintaining the membrane potential may be appreciated by expressing Ohm's law as current = voltage/resistance and recognizing that no current flows when voltage = 0, i.e., transmembrane voltage grad...
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ژورنال
عنوان ژورنال: Nature
سال: 1946
ISSN: 0028-0836,1476-4687
DOI: 10.1038/158622b0