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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.
91

Improved Interflow and Infiltration Algorithms for Distributed Hydrological Models

Liu, Guoxiang January 2010 (has links)
The shallow subsurface controls the partitioning of available energy between sensible and latent heat of the land surface, and the partitioning of available water among evaporation, infiltration, and runoff. It is a key component of both the hydrometeorological system and the terrestrial water cycle. A critical part of any hydrological or hydrometeorological forecast model is therefore the algorithms used to represent the shallow soil processes, which include infiltration, evaporation, runoff, and interflow. For climate models, coupled algorithms called “Land Surface Schemes” (LSSs) are developed to represent the lower boundary conditions that deal with the land-to-atmosphere energy and moisture fluxes. Similar algorithms are implemented in regional watershed models and day-to-day operational water resources forecasting models. It is the primary objective of this thesis to provide improved methods for simulating coupled land surface processes, which can be used as components of LSSs or within existing operational hydrology models. These new methods address a number of specific issues inadequately handled by current models, including the presence of shallow boundary conditions, heterogeneity in infiltration, and infiltration and interflow coupling processes. The main objective of the proposed research is to provide consistent physically-based approach for simulating near surface soil moisture processes, so as to complete the parameterization of the interflow/infiltration algorithm in a Hydrology-Land-Surface scheme MESH. The work mainly focuses on the investigation and development of more physically-based infiltration and interflow algorithms. The hope is to determine appropriate relationships between internal state variables (specifically bulk soil moisture) and system boundary fluxes, while simultaneously reducing the number of nonphysical or unknown model parameters. Fewer parameters lead to reduced calibration requirements for distributed hydrological models and consequently accelerate the transfer of such models to engineering practice. Multiple approaches were taken to provide improved relationships between infiltration and lateral drainage, fluxes and storage. These algorithms were tested by a specialized Richards' equation for sloping soils and Monte Carlo simulations. These tests demonstrated reasonable accuracy and improved representation for the hydrological processes.
92

Infiltration of wind-driven rainfall into plastered straw bale walls

Chase, Matthew 20 August 2009 (has links)
The performance of plastered straw bale walls with respect to wind-driven rainfall was investigated in this thesis. The absorption coefficient, which describes the rate of water infiltration, was measured for 14 plaster types, twelve different earth plasters and cement and lime plasters. The absorption coefficient was measured during uptake of water from a free reservoir. The effective porosity of these plasters, which describes the moisture storage capacity and the degree of protection that a plaster offers to straw bales, was also determined by submersion in water. An analytical model employing the absorption coefficient, the effective porosity, and climatic data was used to predict and compare plaster performance and to demonstrate the usefulness of this type of data. Simulated wind-driven rainfall experiments were also conducted on two plaster types. The results indicate that the static test used to measure the absorption coefficient can reasonably be used to predict actual wind-driven rainfall infiltration.
93

Infiltration of wind-driven rainfall into plastered straw bale walls

Chase, Matthew 20 August 2009 (has links)
The performance of plastered straw bale walls with respect to wind-driven rainfall was investigated in this thesis. The absorption coefficient, which describes the rate of water infiltration, was measured for 14 plaster types, twelve different earth plasters and cement and lime plasters. The absorption coefficient was measured during uptake of water from a free reservoir. The effective porosity of these plasters, which describes the moisture storage capacity and the degree of protection that a plaster offers to straw bales, was also determined by submersion in water. An analytical model employing the absorption coefficient, the effective porosity, and climatic data was used to predict and compare plaster performance and to demonstrate the usefulness of this type of data. Simulated wind-driven rainfall experiments were also conducted on two plaster types. The results indicate that the static test used to measure the absorption coefficient can reasonably be used to predict actual wind-driven rainfall infiltration.
94

礫浜斜面上の流速場と漂砂移動機構に関する研究

馬, 賢鎬, MA, Hyun-Ho, 水谷, 法美, MIZUTANI, Norimi, 江口, 周, EGUCHI, Shu 05 1900 (has links)
No description available.
95

A note on the discoloration and fungal infiltration processes on wood tissues surrounding the gallery system of scolytid beetles

HIJII, Naoki, 肘井, 直樹, KAJIMURA, Hisashi, 梶村, 恒, NISHIBE, Yuuji, 西部, 雄司 12 1900 (has links) (PDF)
農林水産研究情報センターで作成したPDFファイルを使用している。
96

Herstellung von hochschmelzenden Metallmatrix-Verbundwerkstoffen durch Schleudergiessen /

Geldern, Maike van. January 2005 (has links)
Zugl.: Erlangen, Nürnberg, University, Diss., 2005.
97

Big boxes and stormwater

Fite-Wassilak, Alexander H. January 2008 (has links)
Thesis (M. S.)--Architecture, Georgia Institute of Technology, 2009. / Committee Chair: Dagenhart, Richard; Committee Member: Elliott, Michael; Committee Member: Green, David
98

Beschleunigter Stoffaustrag aus Reaktordeponien

Drees, Kornelia Theodora. Unknown Date (has links) (PDF)
Techn. Hochsch., Diss., 2000--Aachen.
99

Elektrische Kenngrößen für die elektroporative Wirkstoff-Einschleusung und den DNA-Transfer in Zentrifugal-Aggregate von CHO-Zellen als Gewebemodell

Schmeer, Marco. Unknown Date (has links) (PDF)
Universiẗat, Diss., 2004--Bielefeld.
100

Structures arborescentes et maillées en hydraulique et hydrologie.

Gaudu, Rémi, January 1900 (has links)
Th.--Math.--Toulouse--I.N.P., 1978. N°: 35.

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