• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 4
  • 2
  • 1
  • Tagged with
  • 8
  • 8
  • 4
  • 4
  • 4
  • 3
  • 3
  • 3
  • 3
  • 3
  • 2
  • 2
  • 2
  • 2
  • 2
  • 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

The movement of water and solutes through saturated and unsaturated structured soil

Abdulkabir, Mokhtar O. January 1989 (has links)
No description available.
2

Formulation & Calibration of a Numerical model of the tidal hydraulics of McCormacks Bay

Flanagan, James P A January 1997 (has links)
The experimental investigation in this report was conducted both as indicator of the problems in McCormacks bay, and also as a base for the calibration of a numerical model of the hydraulic characteristics of the bay. There are some issues of public concern associated with the bay at the present time. These are related to dominant algae populations and their related problems, and the desire to preserve the existing bay as a healthy marine environment. Numerical models can be a useful tool to test various management options. A component of this study involved the calibration of a numerical model which described the response of the bay to tidal functions in the estuary. Calibration was achieved using data from measurements taken on the eighteenth of December 1996. The model was based specifically around the main central culvert running under the causeway. The model showed that an increase in the depth of this culvert would increase the range of water levels in the bay by up to 23%. This is significant and would increase the tidal exchange in the bay, thereby promoting circulation.
3

Hydraulické charakteristiky proudění v kavitačních tryskách / Hydraulic characteristics of the cavitation nozzles

Gríger, Milan January 2013 (has links)
The main goal of this thesis is the examination of hydraulic characteristics for different cavity nozzles, influence of liquid rotation and visualization of cavitating flow. Thesis is divided into two parts, theoretical and practical. Theoretical part deals with the description of cavity - creation, development and its extinction. This part also contains description of vortex flow and basic vertex models. Practical part compares nozzles performance experimentally. The aim of experiment was to measure hydraulic characteristics and their comparison. Jet performance was judged using visualizations and measured data was processed in Microsoft Excel and Parametr.
4

Mapeamento geotécnico para análise de feições erosivas concentradas na bacia do Ribeirão do Meio, São Pedro/SP, na escala 1:20.000 / not available

Gomes, Dirlene Moreira 13 December 2002 (has links)
A bacia do Ribeirão do Meio é uma área com sérios problemas associados ao processo de erosão hídrica. A carta de susceptibilidade à erosão foi obtida a partir do uso combinado de um conjunto de ferramentas de trabalhos como: mapeamento geológico-geotécnico e o geoprocessamento; fundamentais para a definição das potencialidades e limitações do meio físico. Os procedimentos adotados durante o mapeamento geológico-geotécnico permitiram obter informações de caráter qualitativo e quantitativo dos materiais inconsolidados, os quais foram submetidos a um processo de análise para a sua caracterização. Dentre as técnicas de trabalho merece destaque o ensaio de infiltração in situ tanto pela qualidade e importância das informações obtidas, quanto pelo baixo custo financeiro. Os critérios estabelecidos para avaliação dos principais fatores associados ao fenômeno de erosão, foram: índice de erodibilidade, declividade do terreno, espessura dos materiais inconsolidados, textura do material, condutividade hidráulica, origem do material, presença ou não da cobertura vegetal e processo de ocupação das terras. Durante o processo de análise das informações as características hidráulicas e os índices de erodibilidade foram correlacionados a todas outras propriedades dos materiais inconsolidados, e revelaram-se fortes parâmetros de avaliação frente aos processos erosivos. Todas essas informações, foram introduzidas no sistema de tratamento de dados do geoprocessamento para a apresentação em forma de documentos cartográficos e cruzamento das informações que culminaram no reconhecimento de cinco classes susceptíveis à erosão por escoamento concentrado. / This research proposes the elaboration of the Ribeirão do Meio river\'s basin erosion susceptibility map. This area was chosen due to serious problems related to the gully erosion observed on the site. This cartographic document was obtained using tools such as the Geological-Geotechnical Mapping and Geoprocessament; essential to define the physical environment\'s potentialities and limitations. The procedures adopted during the geological-geotechnical mapping made it possible to obtain qualitative and quantitative information of the unconsolidated material, which were analyzed and characterized. The in situ infiltration test must be emphasized among the other work techniques due to its quality, low cost and importance of the obtained information. The criteria established to evaluate the main factors were: erodibility index, declivity, the unconsolidated material\'s thickness, material texture, hydraulic conductivity, the material\'s source, possible presence of vegetable covering and antropic activity process. During the information analysis process, the hydraulic characteristics and the erodibility indexes were correlated to all other properties of the unconsolidated materials, and among the parameters used to evaluate the erosive process the hydraulic characteristics and erodibility indexes provided the most consistent results. Cartographic documents and the other information were crossing culminating on the recognition of five susceptibility classes of erosion for concentrated drainage.
5

Mapeamento geotécnico para análise de feições erosivas concentradas na bacia do Ribeirão do Meio, São Pedro/SP, na escala 1:20.000 / not available

Dirlene Moreira Gomes 13 December 2002 (has links)
A bacia do Ribeirão do Meio é uma área com sérios problemas associados ao processo de erosão hídrica. A carta de susceptibilidade à erosão foi obtida a partir do uso combinado de um conjunto de ferramentas de trabalhos como: mapeamento geológico-geotécnico e o geoprocessamento; fundamentais para a definição das potencialidades e limitações do meio físico. Os procedimentos adotados durante o mapeamento geológico-geotécnico permitiram obter informações de caráter qualitativo e quantitativo dos materiais inconsolidados, os quais foram submetidos a um processo de análise para a sua caracterização. Dentre as técnicas de trabalho merece destaque o ensaio de infiltração in situ tanto pela qualidade e importância das informações obtidas, quanto pelo baixo custo financeiro. Os critérios estabelecidos para avaliação dos principais fatores associados ao fenômeno de erosão, foram: índice de erodibilidade, declividade do terreno, espessura dos materiais inconsolidados, textura do material, condutividade hidráulica, origem do material, presença ou não da cobertura vegetal e processo de ocupação das terras. Durante o processo de análise das informações as características hidráulicas e os índices de erodibilidade foram correlacionados a todas outras propriedades dos materiais inconsolidados, e revelaram-se fortes parâmetros de avaliação frente aos processos erosivos. Todas essas informações, foram introduzidas no sistema de tratamento de dados do geoprocessamento para a apresentação em forma de documentos cartográficos e cruzamento das informações que culminaram no reconhecimento de cinco classes susceptíveis à erosão por escoamento concentrado. / This research proposes the elaboration of the Ribeirão do Meio river\'s basin erosion susceptibility map. This area was chosen due to serious problems related to the gully erosion observed on the site. This cartographic document was obtained using tools such as the Geological-Geotechnical Mapping and Geoprocessament; essential to define the physical environment\'s potentialities and limitations. The procedures adopted during the geological-geotechnical mapping made it possible to obtain qualitative and quantitative information of the unconsolidated material, which were analyzed and characterized. The in situ infiltration test must be emphasized among the other work techniques due to its quality, low cost and importance of the obtained information. The criteria established to evaluate the main factors were: erodibility index, declivity, the unconsolidated material\'s thickness, material texture, hydraulic conductivity, the material\'s source, possible presence of vegetable covering and antropic activity process. During the information analysis process, the hydraulic characteristics and the erodibility indexes were correlated to all other properties of the unconsolidated materials, and among the parameters used to evaluate the erosive process the hydraulic characteristics and erodibility indexes provided the most consistent results. Cartographic documents and the other information were crossing culminating on the recognition of five susceptibility classes of erosion for concentrated drainage.
6

Použití programu Rosetta k odhadu retenčních čar půdní vlhkosti z experimentální plochy Bohaté Málkovice / Using program Rosetta to estimate of soil moisture retention curves from experimental size Bohaté Málkovice

Čermák, Petr January 2015 (has links)
Hydraulic characteristics are the most important properties of soil, i.e. retention curve of soil moisture and hydraulic conductivity. Hydraulic conductivity of soil characterizes the ability of the soil to conduct water. Retention curve expresses the relationship between moisture and moisture potential of soil. The running of retention curve is influenced by many factors, eg. grain size and mineralogical composition, content of humus, reduce bulk density and structure of soil. Measurement of retention curves takes a lot of time and money in laboratory conditions therefore pedotransfer functions seem to be an alternative solution. The thesis aims to estimate moisture retention curves of soil in a selected area of interest in South Moravia using program Rosetta (Schaap, 2003). Data of granularity (% content of clay, sand and dust), bulk density of soil and hydrolimits field water capacity and wilting point were used as predictors in individual models of program Rosetta. Data of grain were matched by FAO / USDA system. Retention curves of soil moisture were measured on a sand tank and overpressure devices. The measured retention curves were parameterized by RETC program. Estimated retention curves were graphically compared with measured to determine the quality of the estimate. The accuracy of the estimate was assessed by correlation coefficient R of determination coefficient R2 and standard error SMRE. Usability own derivatives pedotransfer functions is hard to say due to the size of the input data file. I would recommend further verification of data at the other localities in south Moravia.
7

Stanovení hydraulických charakteristik půdy ve vybraném zájmovém území / Determination of hydraulic characteristics of soil in a selected area

Salač, Jan January 2018 (has links)
The diploma thesis is focused on issues of measurement and evaluation of hydraulic characteristics of soil. In the literary research, the definitions of hydraulic conductivity and retention curve of soil moisture, their measurements in laboratory and field conditions and the prediction of these characteristics by using of pedotransfer functions. In the practical part of the diploma thesis, an evaluation of the hydraulic conductivity of soil from the experimental areas near the village Bohaté Málkovice. Two-cylindrical and mini-disc infiltration meters were used for field measurements, and a constant-gradient permeameter was used in the laboratory. Physical and empirical equations were used to evaluate the hydraulic conductivity. The results were processed numerically, tabulated and then compared.
8

Stanovení hydraulických charakteristik půdy ve vybrané lokalitě / Determination of soil hydraulic characteristics in the selected location

Stoklásková, Adéla January 2012 (has links)
This thesis deals with direct and indirect determination of soil hydraulic characteristics (retention curve and hydraulic conductivity) in the locality of Bohaté Málkovice. For laboratory determination of soil moisture retention curve is used sand tank and pressure relief device. For the indirect determination of soil hydraulic characteristics is used computer software Rosetta, which includes 5 models of pedotransfer functions. For estimatiton of retention curves are applied previously derived pedotransfer function (continuous parametric PTF and point PTF).

Page generated in 0.1093 seconds