3,384 research outputs found

    An estimate of the influence of sediment concentration and type on remote sensing penetration depth for various coastal waters

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    Under the assumptions of collimated light, a homogenous water column, zero molecular scattering, and constant ratio of volume scattering function to scattering coefficient, estimates of the remote sensing depth parameter, Z90, are made for various coastal waters at 540 nm. Calculations indicate that sediment concentration and type have a strong influence on remote sensing depth when concentrations are below 5 mg/theta. Above 5 mg/theta, the absorption coefficient of the sediments becomes large in comparison to that of water, causing Z90 values to be less than 2 m with only small differences between various sediment types

    A regression technique for evaluation and quantification for water quality parameters from remote sensing data

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    The objective of this paper is to define optical physics and/or environmental conditions under which the linear multiple-regression should be applicable. An investigation of the signal-response equations is conducted and the concept is tested by application to actual remote sensing data from a laboratory experiment performed under controlled conditions. Investigation of the signal-response equations shows that the exact solution for a number of optical physics conditions is of the same form as a linearized multiple-regression equation, even if nonlinear contributions from surface reflections, atmospheric constituents, or other water pollutants are included. Limitations on achieving this type of solution are defined

    Calibration of a turbidity meter for making estimates of total suspended solids concentrations and beam attenuation coefficients in field experiments

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    Management of water resources such as a reservoir requires using analytical models which describe such parameters as the suspended sediment field. To select or develop an appropriate model requires making many measurements to describe the distribution of this parameter in the water column. One potential method for making those measurements expeditiously is to measure light transmission or turbidity and relate that parameter to total suspended solids concentrations. An instrument which may be used for this purpose was calibrated by generating curves of transmission measurements plotted against measured values of total suspended solids concentrations and beam attenuation coefficients. Results of these experiments indicate that field measurements made with this instrument using curves generated in this study should correlate with total suspended solids concentrations and beam attenuation coefficients in the water column within 20 percent

    The influence of surface waves on water circulation in a mid-Atlantic continental shelf region

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    The importance of wave-induced currents in different weather conditions and water depths (18.3 m and 36.6 m) is assessed in a mid-Atlantic continental-shelf region. A review of general circulation conditions is conducted. Factors which perturb the general circulation are examined using analytic techniques and limited experimental data. Actual wind and wave statistics for the region are examined. Relative magnitudes of the various currents are compared on a frequency of annual occurrence basis. Results indicated that wave-induced currents are often the same order of magnitude as other currents in the region and become more important at higher wind and wave conditions. Wind-wave and ocean-swell characteristics are among those parameters which must be monitored for the analytical computation of continental-shelf circulation

    Criteria for the use of regression analysis for remote sensing of sediment and pollutants

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    Data analysis procedures for quantification of water quality parameters that are already identified and are known to exist within the water body are considered. The liner multiple-regression technique was examined as a procedure for defining and calibrating data analysis algorithms for such instruments as spectrometers and multispectral scanners

    Sub-Poissonian atom number fluctuations by three-body loss in mesoscopic ensembles

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    We show that three-body loss of trapped atoms leads to sub-Poissonian atom number fluctuations. We prepare hundreds of dense ultracold ensembles in an array of magnetic microtraps which undergo rapid three-body decay. The shot-to-shot fluctuations of the number of atoms per trap are sub-Poissonian, for ensembles comprising 50--300 atoms. The measured relative variance or Fano factor F=0.53±0.22F=0.53\pm 0.22 agrees very well with the prediction by an analytic theory (F=3/5F=3/5) and numerical calculations. These results will facilitate studies of quantum information science with mesoscopic ensembles.Comment: 4 pages, 3 figure

    Alien Registration- Whitlock, Letitia C. (Gorham, Cumberland County)

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    https://digitalmaine.com/alien_docs/31793/thumbnail.jp

    [There is So Much Blood in Us]

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    [There is So Much Blood in Us] is an ambiguously alternate universe in which absolutely nothing is true but almost everything could be. In these poems, tension between the absurd and the possible synthesize into one linguistically and psychologically driving force – discomfort. More than anything, I am writing about discomfort. America’s media representations of women are almost always defined by a singular, and often sexualized experience. Yet, when I talk to the many wonderful / brilliant / badass / etc. women in my life, most of our truly defining experiences are impressively unsexy. Our womanity, if you will, orbits around the gravitational pulls of maternal relationships, vulnerability, and, yes – also periods. Thus, in these poems I place my anatomy into desexualized and uncomfortable moments, in order to emphasize my human corporeality over my sexual corporeality. With [There is So Much Blood in Us], I am challenging societal dehumanization of female bodies, and reminding America that our bodies are occupied

    Alien Registration- Whitlock, Wendle C. (Portland, Cumberland County)

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    https://digitalmaine.com/alien_docs/21996/thumbnail.jp

    Turbid water measurements of remote sensing penetration depth at visible and near-infrared wavelength

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    Remote sensing of water quality is dicussed. Remote sensing penetration depth is a function both of water type and wavelength. Results of three tests to help demonstrate the magnitude of this dependence are presented. The water depth to which the remote-sensor data was valid was always less than that of the Secchi disk depth, although not always the same fraction of that depth. The penetration depths were wavelength dependent and showed the greatest variation for the water type with largest Secchi depth. The presence of a reflective plate, simulating a reflective subsurface, increased the apparent depth of light penetration from that calculated for water of infinite depth
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