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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Sand layer moved on slope bed and breaking wave characteristic of experimental study

Li, Ji-yu 25 July 2008 (has links)
This experimental technique (doctoral dissertation rough draft) designs the construction by Liao, the affiliation observation sand bed section plane change situation seeks has been moving sediment, reference for nearshore drifted sand quantity appraisal. A series of hydraulic model experiments in wave flume are used to investigate the relationships between sand bed section migration and wave condition. Lays down the uniform slope of 1/30 movable-bed in wave flume, and uses two kinds easily to differentiate the nature close sand particle constitution bottom bed. After the wave action, we can find the moved bed section and unmoved part by observed the situation which is mixed by the wave action. From the sand body section plane change situation understood the wave washes the deep degree to the bottom bed. According to Liao (doctoral dissertation rough draft) parameter of the construction: The movable parameter with the breaking wave eddy current coefficient, with has separately moved the granulated substance quantity on its significance to compare.
12

A geomorphological approach to coarse bed-material movement in alluvial channels, with special reference to a small Appalachian stream.

Laronne, Jonathan B. January 1973 (has links)
No description available.
13

The use of Acoustic Doppler Current Profiler technology to quantify total suspended solids under ice

Weiss, Andrew 18 December 2012 (has links)
The measurement of total suspended solids (TSS) concentrations through water quality monitoring programs is laborious, costly, and time-intensive. Winter conditions further hinder water quality monitoring programs. The use of Acoustic Doppler Current Profilers (ADCPs) is currently being explored as a surrogate for estimating total suspended solids concentrations. TSS concentration and ADCP measurements were collected during the winter at the Lower Nelson River and the Red River such that ADCP backscatter data could be calibrated to TSS concentrations. Different calibration schemes were pursued, some involving flow parameters determined from ADCP data, in order to accurately model the data. Due to limited ranges in the data, further TSS concentration and ADCP measurements were taken during the open water period. Calibrations were achieved with varying degrees of accuracy, however the they failed to perform well beyond the ranges for which they were developed.
14

The use of Acoustic Doppler Current Profiler technology to quantify total suspended solids under ice

Weiss, Andrew 18 December 2012 (has links)
The measurement of total suspended solids (TSS) concentrations through water quality monitoring programs is laborious, costly, and time-intensive. Winter conditions further hinder water quality monitoring programs. The use of Acoustic Doppler Current Profilers (ADCPs) is currently being explored as a surrogate for estimating total suspended solids concentrations. TSS concentration and ADCP measurements were collected during the winter at the Lower Nelson River and the Red River such that ADCP backscatter data could be calibrated to TSS concentrations. Different calibration schemes were pursued, some involving flow parameters determined from ADCP data, in order to accurately model the data. Due to limited ranges in the data, further TSS concentration and ADCP measurements were taken during the open water period. Calibrations were achieved with varying degrees of accuracy, however the they failed to perform well beyond the ranges for which they were developed.
15

Sediment transport beneath an undular hydraulic jump

Broome, Robert 30 May 1978 (has links)
Field observations are made of the formation of backwash ripples on the beachface, formed by undular hydraulic jumps generated by backwash down the beach face colliding with wave bores. Measured ripple wavelengths range from set averages of 48 to 70 cm. Within a particular set of ripples there is a tendency for the spacing to decrease in the offshore direction. These field observations are compared with laboratory experiments where undular jumps are generated in a flume, and with a computer simulation model which models both the flow within an undular hydraulic jump and the resulting sediment transport which gives rise to the backwash ripples. The computer model involves a numerical solution of the Boussinesq equations which govern the fluid flow, and sediment transport equations which relate the sand transport rate to the local mean flow velocity. The computer model permits a study of the detailed time-history of the undular jump development and the formation of the backwash ripples. This model shows good agreement with the field observations of backwash ripples, predicting an offshore decrease in their spacing as observed. The laboratory experiments showed a similar result so long as the Froude number of the supercritical flow before the jump occurs is small, on the order of 1.4. Differences between the computer model and experiments were small and arose principally from the neglect of internal friction and surface tension in the model. The study demonstrates the usefulness of the simultaneous application of computer simulation models and laboratory experiments to understand complex flow and sediment transport conditions such as occur on beaches. / Graduation date: 1979 / Best scan available for figures 1 & 2. Original is a black and white photocopy.
16

Reconstructing long term sediment flux from the Brooks Range, Alaska using shelf edge clinoforms

Kaba, Christina Marie. January 1900 (has links)
Thesis (M.S.)--Joint Program in Oceanography/ Applied Ocean Science and Engineering, Massachusetts Institute of Technology and the Woods Hole Oceanographic Institution, 2003. / Title from Web page (viewed on Mar. 24, 2008). Includes bibliographical references (p. 37-40).
17

An evaluation of the distributions of polychlorinated biphenyls and organic matter in coastal sediments /

Jönsson, Anders, January 2004 (has links)
Diss. (sammanfattning) Stockholm : Univ., 2004. / Härtill 4 uppsatser.
18

Studies on boundary conditions for fine-sediment transport /

Dade, William Brian, January 1992 (has links)
Thesis (Ph. D.)--University of Washington, 1992. / Vita. Includes bibliographical references (leaves [239]-260).
19

Acoustic measurements of cohesive sediment transport : suspension to consolidation /

Ha, Ho Kyung, January 2008 (has links) (PDF)
Thesis (Ph. D.)--College of William and Mary. / Vita. Includes bibliographical references.
20

Trace metal distributions and retention factors in Lake Wingra sediments

Imbrigiotta, Thomas E. January 1982 (has links)
Thesis (M.S.)--University of Wisconsin-Madison, 1982. / eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 149-159).

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