Open Access. Powered by Scholars. Published by Universities.®
- Keyword
-
- Hydraulic conductivity (2)
- Kinetics (2)
- Rainfall-runoff (2)
- Air pollution (1)
- Archimedean copula (1)
-
- Biodegradation (1)
- Biofiltration (1)
- Breakthrough (1)
- Cementitious permeable pavement (1)
- Clogging (1)
- Constitutive modeling (1)
- Correlation (1)
- Cosimulation (1)
- Damage in shells (1)
- Dem simulation (1)
- Density fractions (1)
- Dislocation density (1)
- Distribution (1)
- Equilibrium (1)
- Eutrophication (1)
- Filtration (1)
- Flood (1)
- Formation factor (1)
- Fractionation study (1)
- Fungi (1)
- Geophysical logs (1)
- Geostatistics (1)
- Gis (1)
- Granular materials (1)
- Groundwater (1)
Articles 1 - 11 of 11
Full-Text Articles in Engineering
Computational Model For Elasto-Plastic And Damage Analysis Of Plates And Shells, Pawel Benedykt Woelke
Computational Model For Elasto-Plastic And Damage Analysis Of Plates And Shells, Pawel Benedykt Woelke
LSU Doctoral Dissertations
Shells and plates are very important for various engineering applications. Analysis and design of these structures is therefore continuously of interest to the scientific and engineering community. Accurate and conservative assessments of the maximum load carried by the structure, as well as the equilibrium path in both elastic and inelastic range are of paramount importance. Elastic behaviour of shells has been very closely investigated, mostly by means of the finite element method. Inelastic analysis on the other hand, especially accounting for damage effects, has received much less attention from the researchers. A computational model for finite element, elasto-plastic and damage …
Multivariate Hydrological Frequency Analysis And Risk Mapping, Lan Zhang
Multivariate Hydrological Frequency Analysis And Risk Mapping, Lan Zhang
LSU Doctoral Dissertations
In hydrological frequency analysis, it is difficult to apply standard statistical methods to derive multivariate probability distributions of the characteristics of hydrologic or hydraulic variables except under the following restrictive assumptions: (1) variables are assumed independent, (2) variables are assumed to have the same marginal distributions, and (3) variables are assumed to follow or are transformed to normal distribution. Relaxing these assumptions when deriving multivariate distributions of the characteristics of correlated hydrologic and hydraulic variables. The copula methodology is applied to perform multivariate frequency analysis of rainfall, flood, low-flow, water quality, and channel flow, using data from the Amite river …
Experimental Quantification And Dem Simulation Of Micro-Macro Behaviors Of Granular Materials Using X-Ray Tomography Imaging, Yanrong Fu
LSU Doctoral Dissertations
A non-invasive experimental method and a clustering DEM model were developed in this study to investigate micro-macro behaviors of real granular materials with irregular particle shape configurations. The investigated behaviors include global deformations, failure strengths and residual strengths, stress and strain distributions, local coordination number, local void ratio, particle kinematics, and fabric orientation distributions. The experimental method includes an approach to automatically identify and recognize multiple particles using x-ray computed tomography imaging (XCT) and an enhanced approach to digitally represent microstructures of granular materials. The digitally represented microstructure can be directly employed for numerical simulation setup. A compression test and …
Spatial And Temporal Estimation Of Pumping And Recharge In Groundwater System Analysis, Sherly Hartono
Spatial And Temporal Estimation Of Pumping And Recharge In Groundwater System Analysis, Sherly Hartono
LSU Doctoral Dissertations
In many parts of the U.S., groundwater is used as the primary or secondary source of water for the public supply, agricultural, and industrial sectors. In southwestern Louisiana, a majority of the water demand is supplied by the Chicot aquifer. Numerical flow models are useful for managing and optimizing groundwater systems. However, many important model parameters are difficult to quantify, exhibit a certain degree of uncertainty, and may vary both spatially and temporally. Two of the most important and sensitive parameters for a regional groundwater model of the Chicot aquifer are pumping rates and recharge. The use of GIS-based methods …
Speciation, Equilibrium Distribution And Kinetics Of Rainfall-Runoff Phosphorus In Adsorptive-Filtration Unit Operations And Processes, Jia Ma
LSU Doctoral Dissertations
This study examined the influence of hydrology on rainfall runoff phosphorus partitioning between aqueous and particulate-bound phase, and dissolved phosphorus speciation at the upper end of a Cementitious Porous Pavement (CPP) small urban watershed. This study also investigated particulate bound phosphorus temporal distribution during storm event and phosphorus equilibrium distribution on a wide gradation of solids captured by hydrodynamic separator after the storm completed. Results indicate that EMC of urban rainfall runoff phosphorus exceeds EPA water quality criteria, with majority of particulate-bound phosphorus while rainfall by itself contains non-comparable low concentration of phosphorus. Dissolved phosphorus was mainly H2PO4- and HPO4-2 …
Physically Based Multiscale-Viscoplastic Model For Metals And Steel Alloys: Theory And Computation, Farid H. Abed
Physically Based Multiscale-Viscoplastic Model For Metals And Steel Alloys: Theory And Computation, Farid H. Abed
LSU Doctoral Dissertations
The main requirement of large deformation problems such as high-speed machining, impact, and various primarily metal forming, is to develop constitutive relations which are widely applicable and capable of accounting for complex paths of deformation. Achieving such desirable goals for material like metals and steel alloys involves a comprehensive study of their microstructures and experimental observations under different loading conditions. In general, metal structures display a strong rate- and temperature-dependence when deformed non-uniformly into the inelastic range. This effect has important implications for an increasing number of applications in structural and engineering mechanics. The mechanical behavior of these applications cannot …
Pah And Pcb Distribution In Sediment Fractions And Sorptive Phases, Trudy J. Estes
Pah And Pcb Distribution In Sediment Fractions And Sorptive Phases, Trudy J. Estes
LSU Doctoral Dissertations
Contaminant distribution is integral to environmental evaluations of contaminated sediment on every level. The technical and economic feasibility of treatment or beneficial use is a function of the accessibility or separability of the contaminants within the sediment. The magnitude of release to the environment during dredging and disposal is dependent upon the partitioning behavior of the contaminants. Yet, little attention has been paid to contaminant distribution in the fine sediment fractions. Further, conventional distribution coefficients provide little information regarding the relative contaminant loading of each of the sorptive phases. Bioavailability of contaminants in oil and grease, soot and organic carbon, …
Improvements In Groundwater Flow Modeling Through The Integration Of Resistivity Logs And Hydraulic Conductivity And The Use Of Variogram Uncertainty, Asheka Rahman
LSU Doctoral Dissertations
This study developed a coregionalized model to estimate hydraulic conductivity using spatial cross correlation between hydraulic conductivity and borehole geophysical data (a transform of the formation factor). An experimental pseudocross variogram is used instead of a cross variogram because data are not collocated. Experimental variogram uncertainty is investigated using confidence intervals for the experimental variogram calculated assuming variogram sills are lognormally distributed. These intervals are used for sensitivity modeling using kriging, cokriging, simulation and cosimulation. The hydraulic conductivity fields generated by kriging, cokriging, simulation, and cosimulation are then used in a high-resolution groundwater model created using telescopic mesh refinement (TMR) …
Biofiltration For Treatment Of Gas-Phase Voc Mixtures, Bing Qi
Biofiltration For Treatment Of Gas-Phase Voc Mixtures, Bing Qi
LSU Doctoral Dissertations
Biological processes are increasingly used for treatment of air streams contaminated by biodegradable volatile organic compounds (VOCs). The research described in this dissertation involves systematic investigation of various facets of applying biological processes dominated by fungi to remove mixtures of VOCs representative of emissions from paint application and manufacturing. Screening studies were first conducted to assess the ability of multiple fungal species to degrade various industrially important VOCs. In the following phases of the research, studies were conducted to evaluate performance of laboratory-scale bioreactors inoculated with fungi for treatment of mixtures of VOCs representative of emissions from paint spray booths …
Cementitious Permeable Pavement As A Passive Unit Operation And Process For Stormwater Quality And Quantity Control, Xuheng Kuang
Cementitious Permeable Pavement As A Passive Unit Operation And Process For Stormwater Quality And Quantity Control, Xuheng Kuang
LSU Doctoral Dissertations
With respect to the problems caused by impervious pavements, cementitous permeable pavement (CPP) functions as a passive unit operation and process for stormwater quality and quantity control through infiltration, evaporation, filtration, absorption and reaction mechanisms. CPP pore characteristics were examined through pore connectivity analysis using X-Ray Tomography (XRT). Image resolution influence on image analysis results was evaluated. Relationships between parameters of pore characteristics were evaluated. Factors that significantly influence fluid flow in CPP media include effective porosity, pore connectivity and pore size distribution. A modified Kozeny-Carman model in which effective porosity, specific surface area based on effective pores (SSA)pe, and …
Speciation, Equilibria And Kinetics For Rainfall-Runoff Metals In Adsorptive-Filtration Unit Operations And Processes, Tianpeng Guo
Speciation, Equilibria And Kinetics For Rainfall-Runoff Metals In Adsorptive-Filtration Unit Operations And Processes, Tianpeng Guo
LSU Doctoral Dissertations
Populations transferred by rainfall runoff can have many adverse effects livings and people. Treatment of rainfall-runoff continues to pose unique challenges due to the unsteady nature of processes including mobilization, partitioning and transport of heavy metals as well as other constituent loads. BMPs that incorporate heavy metal removal are generating more attention as the nature of stormwater is better understood. This dissertation focused on metal partitioning and speciation in rainfall-runoff through the in-situ Partial Exfiltration Reactor (PER) and exposed to various redox circumstances, and metal removal by sorptive engineered manganese oxides coated media. Adsorption capacity of three manganese oxides coated …