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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.
141

A microcomputer software package to design agricultural drainage plans /

Tremblay, Serge, 1961- January 1987 (has links)
No description available.
142

Meltwater generation and drainage system development on an Antarctic cold-based glacier

MacDonell, Shelley, n/a January 2009 (has links)
Drainage systems on cold-based glaciers are often thought to be simple systems that can be approximated from the supraglacial components of temperate glaciers. Most studies concerning cold-based glacier drainage systems have only considered one facet of the system, with little regard for how the system components interact. Studying each component independently of the whole system constrains our ability to model drainage system function and development. This in turn restricts our potential to predict how drainage systems of cold glaciers may respond to environmental change. The overarching aim of this thesis was to understand drainage system development of a cold-based glacier, and to assess whether our current understanding of supraglacial hydrological systems is consistent with the drainage systems that form on cold-based glaciers. This thesis evaluated the drainage system of the Wright Lower Glacier, McMurdo Dry Valleys, Antarctica, during the 2004/05, 2005/06 and 2006/07 ablation seasons. The study incorporated field, laboratory and numerical analyses, which resulted in a deeper understanding of the spatial and temporal variability of meltwater generation, drainage pathways, water stores and bulk discharge from the glacier. The findings showed that melt variability was driven by sediment and topographic variations, and that water storage in the form of cryoconite holes, intergranular flow, supraglacial ponds and refreezing dictated meltwater transmission to the glacier outlet. These results indicated that the structure, function and variability of the drainage system were inherently more complex than previous studies on supraglacial drainage systems had suggested. These new insights were combined together to construct a new conceptual model of the drainage system structure of a cold-based glacier. However, before the conceptual model can be used to produce a numerical model of drainage system function or development on cold-based glaciers, several issues need to be addressed. These include: refined methods for quantifying meltwater generation in cold, arid environments; methods to measure water storage on and under the glacier surface; further understanding of the development of permeable ice; and a better technique to quantify cryoconite hole connectivity.
143

Pin hole perforations as a filter for drain tubing /

Loong, Seow-phang. January 1983 (has links)
Thesis (M.S.)--Ohio State University, 1983. / Includes bibliographical references (leaves 91-93). Available online via OhioLINK's ETD Center
144

Simulation of bilinear flow in single matrix block drainage

Branajaya, Romi Triaji 17 February 2005 (has links)
This thesis presents modeling of bilinear flow in tight gas wells and its behavior on single matrix block drainage. The objectives of this research are to: simulate a tight gas well using matrix block drainage under constant production pwf and with a constant production rate; be able to predict the behavior of matrix block drainage; study the effect of natural fracture(s) near a well; examine the matrix block drainage in a natural fracture network; and to validate a matrix block drainage model with a hydraulic fracture analytical solution. Two different production scenarios, constant pwf and constant rate, are assigned to a tight gas well in matrix block drainage. Matrix block drainage has two distinct permeabilities; a low permeability matrix serves as the tight gas reservoir with a high permeability streak surrounding the matrix. A well only produces from the high permeability fracture. Models were run with different sensitivity cases toward fracture half length, xf, and fracture permeability kf,. The fracture half-length reflects on a/b aspect ratio. The analytical solution for hydraulic fracture developed by Cinco-Ley and Guppy serves as the validation of matrix block drainage. Analysis on the flow regimes which occurred for different geometries and properties are provided. The log-log diagnostic plot of pseudo-pressure drop/gas rates and the log-log plot of dimensionless pressure derivatives and dimensionless reciprocal production rates are presented. Finally, an attempt to normalize the late time and early time of all geometries and properties is presented to obtain one analytical solution.
145

Simulation of bilinear flow in single matrix block drainage

Branajaya, Romi Triaji 17 February 2005 (has links)
This thesis presents modeling of bilinear flow in tight gas wells and its behavior on single matrix block drainage. The objectives of this research are to: simulate a tight gas well using matrix block drainage under constant production pwf and with a constant production rate; be able to predict the behavior of matrix block drainage; study the effect of natural fracture(s) near a well; examine the matrix block drainage in a natural fracture network; and to validate a matrix block drainage model with a hydraulic fracture analytical solution. Two different production scenarios, constant pwf and constant rate, are assigned to a tight gas well in matrix block drainage. Matrix block drainage has two distinct permeabilities; a low permeability matrix serves as the tight gas reservoir with a high permeability streak surrounding the matrix. A well only produces from the high permeability fracture. Models were run with different sensitivity cases toward fracture half length, xf, and fracture permeability kf,. The fracture half-length reflects on a/b aspect ratio. The analytical solution for hydraulic fracture developed by Cinco-Ley and Guppy serves as the validation of matrix block drainage. Analysis on the flow regimes which occurred for different geometries and properties are provided. The log-log diagnostic plot of pseudo-pressure drop/gas rates and the log-log plot of dimensionless pressure derivatives and dimensionless reciprocal production rates are presented. Finally, an attempt to normalize the late time and early time of all geometries and properties is presented to obtain one analytical solution.
146

A study of soil moisture and soil temperature in relation to tile drainage /

Palmer, Melville Louis. January 1955 (has links)
Thesis (M.S.)--Ohio State University, 1955. / Includes bibliographical references (leaves 41-42). Available online via OhioLINK's ETD Center
147

Critical hydraulic gradients for some soil--drain envelope combinations / Soil--drain envelope combinations.

Bonnell, Robert Boyd. January 1984 (has links)
No description available.
148

Highway grading and drainage

Papageorge, George Thomas 05 1900 (has links)
No description available.
149

The Applicability of Passive Treatment Systems for the Mitigation of Acid Mine Drainage at the Williams Brothers Mine, Mariposa County, California: Bench- and Pilot-Scale Studies

Clyde, Erin Jane 30 January 2008 (has links)
The Williams Brothers Mine is located in Mariposa County, California. Surface waters from the site drain into the south fork of the Merced River and the San Joaquin River Basin. The mine was developed in the 1980s and mined intermittently until 1996. In 1998, concerns of acidic drainage at the site arose. Effluent sampling by Engineering Remediation Resources Group (ERRG) found acid mine drainage (AMD) characterized by a pH of 3.9, sulphate concentrations of 100 mg/L and low metal concentrations of 0.074, 4.60, 1.23, 0.047 and 0.133 mg/L for Cu, Fe, Mn, Ni and Zn, respectively. The aim of this research was to evaluate passive treatment system alternatives for the mitigation of the AMD to meet water quality objectives for the San Joaquin River Basin. A bench-scale study was undertaken which consisted of 3 systems treating synthetic AMD: (1) a peat biofilter to remove dissolved metals followed by an anoxic limestone drain (ALD) to increase alkalinity and pH; (2) a sulfate reducing bacteria (SRB) bioreactor followed by an ALD, in which SRB reduce sulphate to sulfides, generating alkalinity and decreasing metal concentrations via metal sulfide precipitation; and (3) a SRB bioreactor. Synthetic AMD was produced to represent AMD characteristics observed at the site. The peat-ALD system effluent pH was 6.9 and concentrations of Fe and Cu decreased to below water quality objectives with concentrations of 0.008 and 0.06, respectively. The SRB-ALD and SRB system effluents met water quality objectives for pH and Cu, Ni and Zn metal concentrations. The effluent pH for both systems was 6.5. The SRB-ALD system reduced Cu, Ni and Zn to concentrations of 0.004, 0.016 and 0.025 mg/L, respectively. The SRB system reduced metal concentrations for Cu, Ni and Zn 0.006, 0.010 and 0.027 mg/L, respectively. Based on the bench-scale study, the pilot-scale system consisted of a combined passive treatment system containing a peat biofilter, SRB bioreactor and a limestone drain. Pilot-scale testing commenced on May 23rd, 2007. To date, some metal attenuation has been observed, with average effluent concentrations of Cu, Fe, Mn, Ni and Zn equal to <0.005, 0.92, 0.45, <0.005 and 0.049 mg/L, respectively. / Thesis (Master, Geological Sciences & Geological Engineering) -- Queen's University, 2008-01-29 12:42:03.58
150

The capacity of corrugated plastic tubing to support earth loads.

Bolduc, Gilles. January 1982 (has links)
No description available.

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