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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.
1

Sedimentary facies associations of the lower reaches of the Zayandeh river and the Gavkhoni Playa Lake Basin (Esfahan province, Iran)

Pakzad, Hamid Reza. January 2003 (has links) (PDF)
Clausthal, Techn. University, Diss., 2003.
2

Chemical features of the Columbia River plume off Oregon

Cissell, Milton Charles 18 April 1969 (has links)
An intensive chemical investigation, that includes the determinations of salinity, oxygen, nutrients, pH, alkalinity, and total carbon dioxide of the Columbia River plume off the Oregon coast in July 1967 shows the following unique features: 1. Along the axis of the river plume both the salinity minimum and temperature maximum occur. The location of these extrema at zero, ten, twenty meters depths differ considerably, suggesting different patterns of water flow at different depths. 2. Throughout the plume region, at salinities less than 32.5%, the plume water is supersaturated with respect to dissolved oxygen, and a subsurface oxygen maximum exists at the depths of 3.0-50 meters. 3. The relationship between apparent oxygen production by marine organisms and nutrient concentrations shows biological production of dissolved oxygen is a definite cause for the oxygen supersaturation in the plume region. 4. The plume area off Oregon is a source of oxygen transfer from the ocean into the atmosphere. / Graduation date: 1969
3

Physical parameters as tracers of Columbia River water

Evans, Richard H. 03 November 1971 (has links)
Hydrographic and bathythermograph data taken off the Oregon coast during a two week period in August of 1969 were analyzed to determine if heat content and mixed layer depth may be used as indicators of Columbia River plume water. Heat content was found to be a poor indicator of plume water because of large additions of heat to the plume as the waters flowed southward and because the layer over which heat content was integrated (0 to 20 meters) was inconsistent with the depth of the plume. High variability among observations made analysis of mixed layer depth difficult and reduced its utility as an indicator of plume waters. Hydrographic sections taken during the summer months off Oregon from 1960 through 1969 were also examined. The axis of the Columbia River plume was located in 70 instances. The salinity axis was found to lie inshore of the temperature axis by a mean distance of 8.5 nautical miles. This displacement increased downstream and was most pronounced in July and August. A simple model showed the displacement to be the result of a large temperature gradient across the nearshore portion of the plume pynocline. / Graduation date: 1972
4

Prediction of hazardous Columbia River bar conditions

Enfield, David B. 25 May 1973 (has links)
In this study methods were developed for the prediction of wave conditions that are hazardous to navigation at river entrances, with emphasis on applicability to the Columbia River. There are two basic components to the prediction system: (1) a semi-automated spectral method for forecasting the significant height and average period of waves in deep water, and (2) an index of navigation hazard at river entrances that depends on the significant height and average period in deep water and on the mean current and water depth at the entrance. The computerized, deep water forecast method is a hybrid scheme that combines the spectral principles of the Pierson-Neumann-James method with the graphical input techniques of Wilson and the fetch limited spectrum of Liu. The significant heights generated by the method are well verified by winter wave measurements at Newport, Oregon. The hazard index is based on the probability of wave-breaking in water of arbitrary depth and current. The breaking probability is derived under the assumption that wave heights and squared periods are statistically independent and distributed according to a Rayleigh probability density function. The breaking-wave probability and the hazard index depend on the wave steepness in deep slack water and on the depth (relative to the wave period squared) and current (relative to the period) at the river entrance. The dependence on depth and current is achieved in two ways: (1) the limiting steepness (breaking index) k found as a function of relative depth and relative current, and (2) the wave spectrum in water of arbitrary depth and current is found by transformation of the spectrum in deep slack water. The transformation is performed by requiring that the rate of wave energy propagation remain constant. The hazard index is closely related to the probability of breaking swell. At water depths that are typical of river entrances, the hazard index depends strongly on the significant wave height, mean current and depth, but only weakly on the mean wave period (since the breaking height of swell at such depths is only weakly dependent on period). Hindcasts of deep water significant wave heights and hazard indices compared reasonably well with measured heights and Columbia River bar closure periods. Forecasts based on accurate prognostic weather charts should provide similar results. / Graduation date: 1974
5

Natural environments as resources: a case study of the Churchill River diversion of northern Manitoba

Bailey, Ronald D. January 1974 (has links)
No description available.
6

The velocity reversal hypothesis and the implications to the sustainability of pool-riffle bed morphology /

Caamaño, Diego. January 1900 (has links)
Thesis (Ph. D., Civil Engineering)--University of Idaho, December 2008. / Major professor: Peter Goodwin. Includes bibliographical references. Also available online (PDF file) by subscription or by purchasing the individual file.
7

L'Oronte étude de fleuve

Weulersse, Jacques, January 1940 (has links)
Thèse complémentaire--Université de Paris. / "Bibliographie": p. [81].
8

Međunarodnopravni položaj Dunava s osvrtom na ekonomski i politički značaj

Stojković, Momir M. January 1970 (has links)
Thesis--Belgrad, 1964 under title: Dunavska komisija. / At head of title: Momir M. Stojković. Summary in Russian and French. Bibliography: p. 127-134.
9

Der Kagera-Nil, ein Beitrag zur Physiographie Deutsch-Ostafrikas.

Fitzner, Rudolf, January 1899 (has links)
Inaug. Diss.--Friedrichs-Universität. / Vita. Includes bibliographical references.
10

Le Danube et l'application du principe de la liberté de la navigation fluviale ...

Radovanovitch, Voyslav M., January 1925 (has links)
Thèse--Geneva. / Bibliography: p. 319-329.

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