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Changes In Wetland Soil Processes And Ecosystem Functions Six Years After Marsh Creation In Barataria Bay, Louisiana, Erol R. Knaus
Changes In Wetland Soil Processes And Ecosystem Functions Six Years After Marsh Creation In Barataria Bay, Louisiana, Erol R. Knaus
LSU Master's Theses
Louisiana contains about 40% of the conterminous United States coastal and estuarine wetlands but also has the highest rates of wetland loss at around 80% of the total. Approximately 4,900 km2 of coastal land in Louisiana has been lost since 1930. Our study location, Barataria Bay, has one of the highest coastal wetland erosion rates in the nation, at ∼41 km2 per year; and therefore, is a high priority for wetland restoration activities. In 2014, sandy sediment dredged from the bed of the Mississippi River was placed in Barataria Bay as part of a restoration effort. Samples were …
Liability Of The Structural Engineer: Establishing, Quantifying, And Managing Risks, Justin Thomas Ittmann
Liability Of The Structural Engineer: Establishing, Quantifying, And Managing Risks, Justin Thomas Ittmann
LSU Doctoral Dissertations
Liability is an important topic to all practicing professionals—including practicing engineers. However, the topic of liability does not receive the necessary attention required relative to other professions. Further, engineers that desire to learn more about liability in relation to their practice do not have many university options within an engineering curriculum or from outside materials available to a non-legally trained engineer. The goal of the study is to provide a comprehensive overview of liability directed towards an intelligent practicing engineer, while avoiding unnecessary over-simplification of the material. This study initially provides an in depth survey of the legal standard of …
Using Github In Large Software Engineering Classes: An Exploratory Case Study, Miroslav Tushev
Using Github In Large Software Engineering Classes: An Exploratory Case Study, Miroslav Tushev
LSU Master's Theses
GitHub has been recently used in Software Engineering (SE) classes to facilitate col- laboration in student team projects. The underlying tenet is that the technical and social feature of GitHub can help students to communicate and collaborate more effectively as a team as well as help teachers to evaluate individual student contribution more objectively. To shed more light on this, in this case study, we explore the benefits and drawbacks of using GitHub in SE classes. Our study is conducted in a software engineering class of 91 students divided into 18 teams. Our research method includes an entry and an …
Engineering Study Abroad As Strategic Exploration, Emily P. Frank, Amanda B. Macdonald
Engineering Study Abroad As Strategic Exploration, Emily P. Frank, Amanda B. Macdonald
Faculty Publications
No abstract provided.
S16rs Sgfb No. 1 (Baja Sae Engr Conference), Gabrielle Triche
S16rs Sgfb No. 1 (Baja Sae Engr Conference), Gabrielle Triche
Student Senate Enrolled Legislation
No abstract provided.
S16rs Sgfb No. 12 (Igv Comp), David Lawrence, Gabrielle Triche
S16rs Sgfb No. 12 (Igv Comp), David Lawrence, Gabrielle Triche
Student Senate Enrolled Legislation
No abstract provided.
Using Stormwater Modeling In Iterative Site Design: An Integration Of Techniques From Engineering And Landscape Architecture, Brooke Erin Morris
Using Stormwater Modeling In Iterative Site Design: An Integration Of Techniques From Engineering And Landscape Architecture, Brooke Erin Morris
LSU Master's Theses
Landscape Architects currently do not have an efficient method for including stormwater quantities in early stages of their design process. With stormwater control infrastructure and theory rapidly shifting in favor of stormwater management with Green Infrastructure or Low Impact Development technologies (LIDs), landscape architects and planners are increasingly making layout and sizing decisions for stormwater design. Due to the development of modeling tools, it is now possible to rapidly produce quantifiable stormwater values for complex site designs at a range of scales. This paper proposes a methodology for the utilization of the EPA – Stormwater Management Model (SWMM), in conjunction …
Visual Representations Of Gender In Engineering Trade Journals Of Professional Societies During 1998-2012: A Content Analysis Of Hierarchy And Stereotypes, Tracy Ettel Morris
Visual Representations Of Gender In Engineering Trade Journals Of Professional Societies During 1998-2012: A Content Analysis Of Hierarchy And Stereotypes, Tracy Ettel Morris
LSU Doctoral Dissertations
Recruiting and retaining women in engineering have stagnated since the mid-1990's partially due to the marginalization of women in education and the workforce. This research analyzed the quality and quantity of representation of women and men in visual images of professional science and engineering trade journals to illuminate the marginalizing climate of engineering. A mixed methods approach using visual content analysis was performed for a 15-year period during 1998-2012 of three different trade journals of professional societies representing various disciplines of engineering: the first has a low percentage of women, the second has a higher percentage of women, and the …
Lsu Research Fall 2014, Louisiana State University And Agricultural & Mechanical College
Lsu Research Fall 2014, Louisiana State University And Agricultural & Mechanical College
Research Magazine
LSU Research is published annually by the Office of Research & Economic Development, Louisiana State University.
Chronic Toxicity Of Nano Metallics On Red Swamp Crayfish (Procambarus Clarkii) In Laboratory And Mesocosm Studies, Jake Andrew Farlow
Chronic Toxicity Of Nano Metallics On Red Swamp Crayfish (Procambarus Clarkii) In Laboratory And Mesocosm Studies, Jake Andrew Farlow
LSU Master's Theses
Nanotechnology has become integrated in commercial, industrial and medical products, and its use has grown exponentially in the past several years. Although potential applications of nanoparticles (NPs) are numerous, concerns about their water quality, environmental, and human health impacts remain unclear. Crayfish are ubiquitous to streams and wetland habitats, are used as a food source, and inhabit areas that could be impacted by water quality issues. Numerous studies have been conducted on the toxicity of various classes of agricultural pesticides and oils to crayfish (Procambarus clarkii) as a non-target organism. However, there is little evidence published on chronic toxicity of …
Lsu Research Fall 2012, Louisiana State University And Agricultural & Mechanical College
Lsu Research Fall 2012, Louisiana State University And Agricultural & Mechanical College
Research Magazine
LSU Research is published annually by the Office of Research & Economic Development, Louisiana State University.
F07rs Sgr No. 3 (Taylor Hall Maps), Jackson, Iseral
F07rs Sgr No. 3 (Taylor Hall Maps), Jackson, Iseral
Student Senate Enrolled Legislation
No abstract provided.
Juvenile Crawfish (Procambarus Clarkii) Lc50 Mortality From South Louisiana Crude, Peanut And Mineral Oil, Okey Umejuru
Juvenile Crawfish (Procambarus Clarkii) Lc50 Mortality From South Louisiana Crude, Peanut And Mineral Oil, Okey Umejuru
LSU Master's Theses
Nearly every continent has species of crawfish that inhabit wetlands or are near coastal areas where petroleum and other oils are produced, transported, and accidentally released. Most crawfish cannot tolerate polluted water. Thus, they could serve as biomonitors of fossil fuel, biofuel, and other oil releases and assess potential negative impacts such oils have on wetland and coastal ecosystems. The objectives of this study were to estimate the acute toxicity of three oils to juvenile crawfish and determine if toxicity was due to poisoning or interference with oxygen transfer across the gills. Juvenile crawfish (Procambarus clarkii) were tested for acute …
Application Of Ozonated Water Technology For Improving Quality And Safety Of Peeled Shrimp Meat, Amrish Suresh Chawla
Application Of Ozonated Water Technology For Improving Quality And Safety Of Peeled Shrimp Meat, Amrish Suresh Chawla
LSU Master's Theses
Ozone is an effective sanitizing agent against a broad spectrum of pathogenic and spoilage organisms. Optimization of treatment applications of ozonated water is needed for increased use in the food industry. An experimental apparatus and process has been developed to digitally measure ozone concentrations in processing water at the point of product application. Two application methods were evaluated. Ozone concentrations were measured rapidly at the point of product application. Shrimp samples were either sprayed or soaked for 20, 40 or 60 seconds with similar volumes of water with dissolved ozone levels of 1, 2, or 3 ppm. Microbial destruction using …
Numerical Simulations Of Incompressible Flows In Complex Geometries., Konstantinos Vogiatzis
Numerical Simulations Of Incompressible Flows In Complex Geometries., Konstantinos Vogiatzis
LSU Historical Dissertations and Theses
A mainly spectral code along with domain-decomposition, a combination that is not widely in use in complex problems, has been developed for the solution of the 3-D unsteady incompressible Navier-Stokes equations. The code uses fully spectral or a combination of spectral-collocation and finite difference approximations and a 3-step splitting time-marching scheme. The developed Poisson solver utilizes matrix diagonalization and incorporates a direct sub-structuring method based on the influence matrix technique. As a first step, laminar and turbulent confined flows were simulated, initially with DNS, then with LES, using a modified Smagorinksi model. The domain-decomposition technique and parallel implementation were tested …
Analysis And Mathematical Modeling Of Autonomously Oscillating Yeast Cultures., Abdelqader M. Zamamiri
Analysis And Mathematical Modeling Of Autonomously Oscillating Yeast Cultures., Abdelqader M. Zamamiri
LSU Historical Dissertations and Theses
The conditions that precede the onset of autonomous oscillations in continuous yeast cultures were studied in three different types of experiments. It was found that the final state of the culture depends on the protocol used to start-up the reactor. Reaching the desired operating point by slow dilution rate changes gave rise to different final states, two oscillatory states and one steady state, depending on the rate of change in dilution rate. The multiplicity of stable states at a single operating point is not explained by current distributed models and points towards a segregated mechanism of these oscillations. The ability …
Novel Formulation And Application Of Model Predictive Control., Guang-Yan Zhu
Novel Formulation And Application Of Model Predictive Control., Guang-Yan Zhu
LSU Historical Dissertations and Theses
Model predictive control (MPC) has been extensively studied in academia and widely accepted in industry. This research has focused on the novel formulation of model predictive controllers for systems that can be decomposed according to their nonlinearity properties and several novel MPC applications including bioreactors modeled by population balance equations (PBE), gas pipeline networks, and cryogenic distillation columns. Two applications from air separation industries are studied. A representative gas pipeline network is modeled based on first principles. The full-order model is ill-conditioned, and reduced-order models are constructed using time-scale decomposition arguments. A linear model predictive control (LMPC) strategy is then …
Active Control Of Thermoacoustical Instabilities., Daniel Ulises Campos-Delgado
Active Control Of Thermoacoustical Instabilities., Daniel Ulises Campos-Delgado
LSU Historical Dissertations and Theses
This dissertation presents some advances in active control of thermoacoustic instabilities in combustion chambers. Large-size gaseous and liquid fueled swirl stabilized combustors were used during the studies. Active control was implemented using different types of actuators. Proportional (loudspeakers and fuel valves) and discrete actuators (open-close automotive fuel injectors) were investigated. Acoustic and fuel modulation control were successfully applied. In large-scale combustors, flame stabilization techniques such as swirl add three dimensional characteristics to the flow. Moreover, the induced turbulence creates highly nonlinear interactions in the system. Thus, in order to capture these characteristics nonlinear partial differential equations have to be used. …
Design, Fabrication, And Testing Of Cross Flow Micro Heat Exchangers., Chad Randall Harris
Design, Fabrication, And Testing Of Cross Flow Micro Heat Exchangers., Chad Randall Harris
LSU Historical Dissertations and Theses
Cross flow micro heat exchangers were designed to maximize heat transfer from a liquid (water) to a gas (air) for a given frontal area while holding the pressure drop across the heat exchanger of each fluid to values characteristic of conventional scale heat exchangers (car radiators). The cross flow micro heat exchanger design is unique since it produces a very high rate of heat transfer/volume between dissimilar fluids with low fluid pressure drops. Predicted performance for two types of cross flow micro heat exchangers is compared to each other and to current innovative car radiators. Although the cross flow micro …
Control Of Supply Chain Systems By Kanban Mechanism., Shaojun Wang
Control Of Supply Chain Systems By Kanban Mechanism., Shaojun Wang
LSU Historical Dissertations and Theses
This research studies the control mechanism of a supply chain system to operate it efficiently and economically under the just-in-time (JIT) philosophy. To implement a JIT system, kanbans are employed to link different plants' production processes in a supply pipeline. Supply chain models may be categorized into single-stage, multi-stage, and assembly-line types of production systems. In order to operate efficiently and economically, the number of kanbans, the manufacturing batch size, the number of batches, and the total quantity over one period are determined optimally for these types of supply chains. The kanban operation at each stage is scheduled to minimize …
Plant Uptake Of Desorption Resistant Organic Chemicals From Sediments., Cesar Miguel Gomez Hermosillo
Plant Uptake Of Desorption Resistant Organic Chemicals From Sediments., Cesar Miguel Gomez Hermosillo
LSU Historical Dissertations and Theses
Two types of wetland plants, a woody species, black willow ( Salix nigra), and a non-woody, the macrophyte three-square bulrush (Scirpus olneyi), were used in laboratory studies to evaluate relationships between sorption, plant uptake, translocation and transpiration of phenanthrene, a model polycyclic aromatic hydrocarbon and chlorobenzene, a model chlorinated benzene from the reversible and desorption-resistant compartment of a sediment for Phenanthrene (PHEN) and a wetland soil for chlorobenzene (CB). The wetland soil is from The Petro Processors Inc. site (PPI), a 77-acre CERCLA facility located about 10 miles north of Baton Rouge, Louisiana. Other studies have evaluated the plant uptake …
A Study Of The Applicability Of Intrusion Technology For Evaluating Resilient Modulus Of Subgrade Soil., Ananda H. M. P. J Herath
A Study Of The Applicability Of Intrusion Technology For Evaluating Resilient Modulus Of Subgrade Soil., Ananda H. M. P. J Herath
LSU Historical Dissertations and Theses
The cone penetration test may be applied for estimation of the resilient modulus of subgrade soil. The main objectives of this study were to assess the applicability of the intrusion technology in evaluating the resilient characteristics of subgrade soil, develop models among the cone penetration test parameters, resilient modulus, soil properties, and stresses of subgrade soil, and to validate these models. Field cone penetration and laboratory tests were performed on different soil types. Disturbed and undisturbed soil samples were obtained close to the cone penetration test locations. Laboratory tests were also performed to obtain the resilient modulus, strength parameters, compaction …
Robust Control Of Uncertain Time -Delay Systems., Yun-Ping Huang
Robust Control Of Uncertain Time -Delay Systems., Yun-Ping Huang
LSU Historical Dissertations and Theses
Time-delay systems are common in industries. Direct analysis and synthesis of control systems with time delays are complicated and approximation methods such as Pade approximation are usually applied. However, the issues of control system robustness with respect to model uncertainties and approximation errors have not been sufficiently addressed. This dissertation focus on robustness of time-delay systems, especially robustness with respect to time delays, which has been discussed extensively using Lyapunov second method. We propose two methods in this dissertation to reformulate the problems into standard mu or Hinfinity problems. The first method involves representing the systems in linear functional transformation …
Mass Transfer Of 2,4,6-Trinitrotoluene And Lower Chlorinated Benzenes From Sediment Into Water., Marti Charleen Blad
Mass Transfer Of 2,4,6-Trinitrotoluene And Lower Chlorinated Benzenes From Sediment Into Water., Marti Charleen Blad
LSU Historical Dissertations and Theses
Bioremediation and phytoremediation are in their infancy and this research addresses concerns for application of these technologies. This laboratory and mathematical modeling effort predicts the pollutant flux from soils and sediments to the overlying waters. Little work has been done on transport in surface waters such as the slow moving and stagnant areas of the southern U.S. Mass transfer is a proposed rate limiting factor for biological transformation when using phytoremediation or natural attenuation. The research quantified mass transport of two dfferent contaminants, TNT and chlorinated benzenes, under different advective conditions. The TNT study was part of a "riffle-bed reactor" …
Development And Characterization Of Velocity Workspaces For The Human Knee., John Eric Fuller
Development And Characterization Of Velocity Workspaces For The Human Knee., John Eric Fuller
LSU Historical Dissertations and Theses
The knee joint is the most complex joint in the human body. A complete understanding of the physical behavior of the joint is essential for the prevention of injury and efficient treatment of infirmities of the knee. A kinematic model of the human knee including bone surfaces and four major ligaments was studied using techniques pioneered in robotic workspace analysis. The objective of this work was to develop and test methods for determining displacement and velocity workspaces for the model and investigate these workspaces. Data were collected from several sources using magnetic resonance imaging (MRI) and computed tomography (CT). Geometric …
Material Properties And Characteristics For Development Of An Expert System For Coal -Tar Sealers., James Edwin Shoenberger
Material Properties And Characteristics For Development Of An Expert System For Coal -Tar Sealers., James Edwin Shoenberger
LSU Historical Dissertations and Theses
Coal-tar sealers are used to protect asphalt pavements from damage by fuel spillage. The durability of these coal-tar sealers has been limited by the formation of cracks that occur in both in trafficked and non-trafficked areas and in all climatic regions. This cracking severely limits the useful life of the coal-tar sealer. Various coal-tar mixtures were evaluated through existing standard test methods. The mixtures varied through the source of the coal-tar emulsion, amount of aggregate, and amount of polymer used in the mixtures. The material properties of these mixtures were determined through curing, thermal, bending, tensile and stress-relaxation testing. The …
Biodegradation Of Desorption -Resistant Organic Contaminants In Wetland Soils., Sangjin Lee
Biodegradation Of Desorption -Resistant Organic Contaminants In Wetland Soils., Sangjin Lee
LSU Historical Dissertations and Theses
Contaminant bioavailability depends on physicochemical processes such as adsorption/desorption, diffusion, and dissolution. The rates of sorption and desorption of trichloroethylene (TCE) and 1,3-Dichlororbenzene (1,3-DCB) were studied. Desorption kinetics of 3-month and 5-month old contaminated soils showed that progressively less amount of contaminant was available for facile desorption compared to freshly contaminated soil in an empirical non-linear model. Microcosm batch studies were conducted to study the biodegradation of 1,3-DCB in the aqueous and soil phase containing a freshly contaminated soil and a soil containing only the desorption resistant fraction. The presence of the soil reduced the rates of biodegradation. It is …
Investigation Of Amphoteric Materials For Treatment Of Heavy Metals In Storm Water., Dingfang Liu
Investigation Of Amphoteric Materials For Treatment Of Heavy Metals In Storm Water., Dingfang Liu
LSU Historical Dissertations and Theses
Urban storm water runoff mobilizes and transports significant loads of heavy metals. Promulgation of NPDES Phase II regulations has spurred development of Best Management Practices (BMPs) for in-situ control of heavy metals. In this study, Amphoteric materials such as manganese oxides and iron oxides on the various substrates including silica sands, polymeric beads and cementitious particles were investigated. Surface characterization results indicated that oxide coatings ranged from 20 to 200-mum in depth, and surface areas were significantly increased by greater than a factor of one thousand compared to uncoated media. Point of zero charge (PZC) for manganese oxide coated media …
A Neural Network Approach To Dependent *Reliability Estimation., Roya Javadpour
A Neural Network Approach To Dependent *Reliability Estimation., Roya Javadpour
LSU Historical Dissertations and Theses
This research presents the creation of a new model for automating the generation of component and system reliability estimates from simulated field data for tightly coupled systems. The model utilizes the CMAC neural network architecture, which resembles the human cerebellum and is capable of approximating nonlinear functions. An analysis and testing of the network as a tool for reliability prediction of dependent components within an assembly has been performed. In order to evaluate the performance of the model, the network has been tested on simulated data and provided over 90% performance accuracy in learning non-linear functions that represent the dependency …
Ergonomic Evaluation Of Manually Operated Valves., Eileen Bordelon Hoff
Ergonomic Evaluation Of Manually Operated Valves., Eileen Bordelon Hoff
LSU Historical Dissertations and Theses
Due to the large number of facilities that produce oil and gas with numerous valves used, a review of valve handwheel operation was of interest. Review of literature on two handed handwheel tasks yielded very little and raised questions about what amount of torque a user could exert on a handwheel. The objectives of this research were to determine the effects of height of exertion, orientation of the handwheel and type of handwheel while making two-handed torque exertions, test a custom designed handwheel against commonly distributed handwheels and to determine the effects of gloves commonly used in the oil and …