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The Worst Case Discharge Scenario, Noah Mcgill Apr 2011

The Worst Case Discharge Scenario, Noah Mcgill

Honors Theses

No abstract provided.


Two-Dimensional Numerical Modeling Of A Proposed Freshwater Diversion From The Bonnet Carre Spillway To The Labranche Wetlands, Josef Patrick Hoffmann Jan 2011

Two-Dimensional Numerical Modeling Of A Proposed Freshwater Diversion From The Bonnet Carre Spillway To The Labranche Wetlands, Josef Patrick Hoffmann

LSU Master's Theses

Engineered modifications to the lower Mississippi River within the past century have limited the magnitude and frequency of flood events in wetlands along the Louisiana coast. Without this natural delivery of freshwater, sediment, and nutrients, the ecological health of these wetlands are now degrading. A recent study within the Bonnet Carre Spillway has revealed that the 7,623 acres of floodway between the Mississippi River and Lake Pontchartrain is one of the few areas in Louisiana that is actively accreting land as a result of pulsed sediment-laden freshwater input during high discharge events in the Mississippi River. On the other hand, …


Electrochemical Reduction Of Co2 To Methanol, Minh Tuyen Hoang Le Jan 2011

Electrochemical Reduction Of Co2 To Methanol, Minh Tuyen Hoang Le

LSU Master's Theses

An efficient method to convert CO2 to fuels using renewable energy could displace crude oil without increasing CO2 emission and provide high-density energy storage reservoirs similar to liquid fuels or batteries. Although photoelectrochemical conversion of CO2 is possible, solar-to-fuel efficiencies are lower than the combination of conventional photovoltaics (up to 40% efficiency) and electrochemical cells (up to 80% Faradaic efficiency). In the electrochemical case, electrical energy from renewable sources may be converted to hydrocarbons or alcohols using electrocatalysts. The direct reduction of CO2 to CH3OH is known to occur at several types of electrocatalysts including oxidized Cu electrodes. In this …


An Euler Solver For Nonlinear Water Waves Using A Modified Staggered Grid And Gaussian Quadrature Approach, Qi Fan Jan 2011

An Euler Solver For Nonlinear Water Waves Using A Modified Staggered Grid And Gaussian Quadrature Approach, Qi Fan

LSU Master's Theses

A structured, finite-volume Euler solver for non-hydrostatic, free surface flows is developed to simulate coastal nonlinear dispersive water waves. A semi-implicit projection method which splits the pressure term into hydrostatic and non-hydrostatic parts is employed. A vertically shifted, staggered grid is designed to accommodate a new Gaussian discharge calculator and to facilitate the enforcement of a non-hydrostatic free-surface boundary condition. The Gaussian discharge calculator on the shifted grid increases the dispersion accuracy compared to traditional approaches that calculate discharges on a regular staggered grid. Numerical results are presented to demonstrate the improvements of these methods.


Communication-Constrained Feedback Stability And Multi-Agent System Consensusability In Networked Control Systems, Laurentiu Dan Marinovici Jan 2011

Communication-Constrained Feedback Stability And Multi-Agent System Consensusability In Networked Control Systems, Laurentiu Dan Marinovici

LSU Doctoral Dissertations

With the advances in wireless communication, the topic of Networked Control Systems (NCSs) has become an interesting research subject. Moreover, the advantages they offer convinced companies to implement and use data networks for remote industrial control and process automation. Data networks prove to be very efficient for controlling distributed systems, which would otherwise require complex wiring connections on large or inaccessible areas. In addition, they are easier to maintain and more cost efficient. Unfortunately, stability and performance control is always going to be affected by network and communication issues, such as band-limited channels, quantization errors, sampling, delays, packet dropouts or …


Numerical Studies Of Flow In Porous Media Using An Unstructured Approach, Nathan Matthew Lane Jan 2011

Numerical Studies Of Flow In Porous Media Using An Unstructured Approach, Nathan Matthew Lane

LSU Doctoral Dissertations

Flow and transport in porous media is relevant to many areas of engineering and science including groundwater hydrology and the recovery of oil and gas. Porous materials are characterized by the unique shape and connectivity of the internal void structures which give rise to a large range in macroscopic transport properties. Historically an inability to accurately describe the internal pore-structure has prevented detailed study of the role of pore structure on transport. In recent decades however, the combination of high resolution imaging technologies with computational modeling has seen the development of fundamental pore-scale techniques for studying flow in porous media. …


Polymer Based Microfabrication And Its Applications In Optical Mems And Biomems, Guocheng Shao Jan 2011

Polymer Based Microfabrication And Its Applications In Optical Mems And Biomems, Guocheng Shao

LSU Doctoral Dissertations

Due to its ease of fabrication, low cost and great variety of functionalities, polymer has become an important material in microfabrication. MEMS devices with polymer as the structure material have found applications in various fields, especially in BioMEMS and optical MEMS. In this dissertation, three polymer based microfabricated devices/components have been developed and tested. Various polymer based fabrication techniques, such as high aspect ratio SU-8 photolithography, three dimensional polydimethylsiloxane (PDMS) soft lithography, multi-layer soft lithography and PDMS double casting technique have been developed/studied and employed in the device fabrication process. The main contribution of this dissertation includes: (1) Developed two …


The Effect Of Exopolymers On The Compressibility And Shear Strength Of Kaolinite, Rick Alton Nugent Jan 2011

The Effect Of Exopolymers On The Compressibility And Shear Strength Of Kaolinite, Rick Alton Nugent

LSU Doctoral Dissertations

Erosion and subsidence threaten coastal infrastructure and natural habitats throughout the coastal United States, and this threat is especially significant along the Louisiana coastline since wetland clays are generally weak and highly compressible. Hydraulic pumping of dredged sediment is a common method for combating damage caused by erosion and subsidence, but the high water content slurry deposited is very compressible with low shear strength. Although conventional soil amendments are effective for reducing compressibility and increasing shear strength, these stabilizers are often caustic or toxic, making them too risky to use. Exopolymers, however, have the potential to improve sediment stability without …


Characterization Of Novel Akermanite:Poly-E-Caprolactone Scaffolds For Bone Tissue Engineering Aapplications Combined With Human Adipose-Derived Stem Cells, Andre S. Zanetti Jan 2011

Characterization Of Novel Akermanite:Poly-E-Caprolactone Scaffolds For Bone Tissue Engineering Aapplications Combined With Human Adipose-Derived Stem Cells, Andre S. Zanetti

LSU Doctoral Dissertations

The development of porous materials useful as scaffolds for the sustained three-dimensional (3D) growth of human adipose-derived stem cells (hASC) is of particular interest to facilitate healing after musculoskeletal injuries. In this study, a composite porous material obtained by blending akermanite with poly-e-caprolactone (PCL) is proposed as novel alternative to bone tissue regeneration. The objectives of this study are (1) to characterize the akermanite:PCL scaffold properties; (2) to investigate the in vitro osteogenic potential of hASC loaded to optimal akermanite:PCL scaffolds; (3) to assess the metabolic activity and osteogenesis of hASC loaded to optimal akermanite:PCL scaffolds post-thawing using optimal cryopreservation …


Decoupling User Interface Design Using Libraries Of Reusable Components, Rajesh Sankaran Jan 2011

Decoupling User Interface Design Using Libraries Of Reusable Components, Rajesh Sankaran

LSU Doctoral Dissertations

The integration of electronic and mechanical hardware, software and interaction design presents a challenging design space for researchers developing physical user interfaces and interactive artifacts. Currently in the academic research community, physical user interfaces and interactive artifacts are predominantly designed and prototyped either as one-off instances from the ground up, or using functionally rich hardware toolkits and prototyping systems. During this prototyping phase, undertaking an integral design of the interface or interactive artifact’s electronic hardware is frequently constraining due to the tight couplings between the different design realms and the typical need for iterations as the design matures. Several current …


Pore-Scale Lattice Boltzmann Simulations Of Inertial Flows In Realistic Porous Media: A First Principle Analysis Of The Forchheimer Relationship, Chukwudi Paul Chukwudozie Jan 2011

Pore-Scale Lattice Boltzmann Simulations Of Inertial Flows In Realistic Porous Media: A First Principle Analysis Of The Forchheimer Relationship, Chukwudi Paul Chukwudozie

LSU Master's Theses

With recent advances in the capabilities of high performance computing (HPC) platforms and the relatively simple representation of complex geometries of porous media, lattice Boltzmann method (LBM) has gained popularity as a means of solving fluid flow and transport problems. In this work, LBM was used to obtain flow parameters of porous media, study the behavior of these parameters at varying flow conditions and quantify the effect of roughness on the parameters by relating the volume averaged flow simulation results to Darcy and Forchheimer equations respectively. To validate the method, flow was simulated on regular and random sphere arrays in …


Performance Assessment Of Innovative Framing Systems Through Building Information Modeling Based Energy Simulation, Santhosh Reddy Chinnayeluka Jan 2011

Performance Assessment Of Innovative Framing Systems Through Building Information Modeling Based Energy Simulation, Santhosh Reddy Chinnayeluka

LSU Master's Theses

While many residential contractors, architects, and home-buyers today are concerned about the environment and interested in sustainable construction technologies, the perceived higher initial costs of innovative materials and methodologies and a lack of life-cycle cost and performance data present significant barriers in the implementation of such techniques. Research regarding an integrated design process has suggested that performance based decision making is key to the successful implementation of sustainable building practices. Therefore, a need exists for the development of whole building design and evaluation models to allow decision making in all phases of a building project. This research seeks information regarding …


Modeling Of First-Flush Reactor For Stormwater Treatment, Shaowei Sun Jan 2011

Modeling Of First-Flush Reactor For Stormwater Treatment, Shaowei Sun

LSU Master's Theses

Stormwater runoff is one of the most common sources of non-point source water pollution to lakes, rivers and estuaries. Nitrate-nitrogen in stormwater runoff is an important limiting factor to the eutrophication phenomenon. While most pollutants and nutrients, including nitrate-nitrogen, in stormwater are discharged into receiving waters during the first-flush period, no existing Best Management Practices (BMPs) are specifically designed to capture and treat the first-flush portion of urban stormwater runoff. In addition, nitrate-nitrogen removal rates of most existing BMPs are relatively low. This thesis presents results from both laboratory experiments and numerical modeling of nitrate-nitrogen removal in a designed first-flush …


Network Traffic Data Analysis, Harish Kapri Jan 2011

Network Traffic Data Analysis, Harish Kapri

LSU Master's Theses

The desire to conceptualize network traffic in a prevailing communication network is a facet for many types of network research studies. In this research, real traffic traces collected over trans-Pacific backbone links (the MAWI repository, providing publicly available anonymized traces) are analyzed to study the underlying traffic patterns. All data analysis and visualization is carried out using Matlab (Matlab is a trademark of The Mathworks, Inc.). At packet level, we first measure parameters such as distribution of packet lengths, distribution of protocol types, and then fit following analytical models. Next, the concept of flow is introduced and flow based analysis …


Boron And Rare Earth Oxide Composite Nanoparticles For Enhancement Of Combustion, Jacob Hanberry Jan 2011

Boron And Rare Earth Oxide Composite Nanoparticles For Enhancement Of Combustion, Jacob Hanberry

LSU Master's Theses

Metallic fuels are of interest as additives in bio-fuel combustion because of their high heating values, and this thesis deals with the experimental investigation of boron nanoparticles and their effect on ethanol combustion. Two grades of boron nanoparticles were commercially purchased and modified to obtain different physical characteristics, by ball milling and sintering. Also, a mixture of rare-earth oxide (CeO2, La2O3, and Gd2O3) nanoparticles was synthesized and added to the boron nanoparticles in varying amounts to form composite mixtures. The effects of rare-earth oxides on boron combustion were investigated using these composites. Particle characterizations were carried out by X-ray diffraction, …


Building Information Management (Bim) Implementation In Naval Construction, Raymond Rohena Jan 2011

Building Information Management (Bim) Implementation In Naval Construction, Raymond Rohena

LSU Master's Theses

Traditional two-dimensional (2D) delivery systems in the construction industry can hinder the way information is communicated between owners, architects, and contractors. This hindrance exists in all phases of a project, from design and construction to the operation and maintenance of the completed facility. Building Information Management (BIM) is an emerging information technology that promotes a collaborative process for the Architectural, Engineering, Construction and Facilities Management (AECFM) industry; it can aid the exchange of information and provide improved project data accessibility to all stakeholders of a construction project. The Naval Facilities Engineering Command (NAVFAC), in conjunction with the facility management (FM) …


Integrating Multiple Clusters For Compute-Intensive Applications, Zhifeng Yun Jan 2011

Integrating Multiple Clusters For Compute-Intensive Applications, Zhifeng Yun

LSU Doctoral Dissertations

Multicluster grids provide one promising solution to satisfying the growing computational demands of compute-intensive applications. However, it is challenging to seamlessly integrate all participating clusters in different domains into a single virtual computational platform. In order to fully utilize the capabilities of multicluster grids, computer scientists need to deal with the issue of joining together participating autonomic systems practically and efficiently to execute grid-enabled applications. Driven by several compute-intensive applications, this theses develops a multicluster grid management toolkit called Pelecanus to bridge the gap between user's needs and the system's heterogeneity. Application scientists will be able to conduct very large-scale …


A Study Of A Smog-Fog-Smog Cycle And The Processing Of Pah And Oxy-Pah By A Fog Cloud, Kalindi Pramod Khadapkar Jan 2011

A Study Of A Smog-Fog-Smog Cycle And The Processing Of Pah And Oxy-Pah By A Fog Cloud, Kalindi Pramod Khadapkar

LSU Master's Theses

Fog is a multiphase dynamic system which can provide a setting for various physicochemical processes affecting the fate of various organic pollutants such as polycyclic aromatic hydrocarbons (PAH) and their oxygenated forms (oxy-PAH) in the atmosphere. This study focuses on the processing of PAH and oxy-PAH during a smog-fog-smog cycle. Two field campaigns were carried out during the winters of year 2010 and year 2011 in the Central Valley of California, sampling two fog events in Fresno and five fog events in Davis. To study the transformations and distributions of PAH and oxy-PAH, different atmospheric species (fog water, gas phase, …


Evaluation Of Simultaneous Water And Gas Injection Using Co2, Shrinidhi Shetty Jan 2011

Evaluation Of Simultaneous Water And Gas Injection Using Co2, Shrinidhi Shetty

LSU Master's Theses

Miscible CO2 injection is the second largest contributor to global enhanced oil recovery, as it has successfully undergone extensive laboratory tests and field applications for recovering residual oil left behind after waterflooding. Prolific incremental recoveries have been obtained for some fields. Although miscible CO2 injections generally have excellent microscopic displacement efficiency they often result in poor sweep efficiency. In order to address sweep problems and maximize recoveries, other schemes of gas injection have been developed. Two such processes are water-alternating-gas (WAG) and simultaneous water-and-gas (SWAG) injection. WAG and SWAG have been successfully used to minimize poor sweep. Improved gas utilization …


Server Assignment In Mirrored Server Environments, Shawn Farlow Jan 2011

Server Assignment In Mirrored Server Environments, Shawn Farlow

LSU Master's Theses

Massively multiplayer online games (MMOGs) may use peer-to-peer, client-server, or mirrored-server environments. Since there exist multiple server options in mirrored server environments, a problem arises when deciding to which server each player should connect. We propose three distinct algorithms that assign players within Quality of Service (QoS) as each player joins and leaves, taking into consideration whether a player already in QoS can be moved to place a newly joining player in QoS without sacrificing QoS for the moved player. Our results show that for certain numbers of servers and values of QoS, our algorithms increase the total number of …


Efficient And Robust Signal Detection Algorithms For The Communication Applications, Lu Lu Jan 2011

Efficient And Robust Signal Detection Algorithms For The Communication Applications, Lu Lu

LSU Doctoral Dissertations

Signal detection and estimation has been prevalent in signal processing and communications for many years. The relevant studies deal with the processing of information-bearing signals for the purpose of information extraction. Nevertheless, new robust and efficient signal detection and estimation techniques are still in demand since there emerge more and more practical applications which rely on them. In this dissertation work, we proposed several novel signal detection schemes for wireless communications applications, such as source localization algorithm, spectrum sensing method, and normality test. The associated theories and practice in robustness, computational complexity, and overall system performance evaluation are also provided.


Working Active Power, Reflected Active Power, And Detrimental Active Power In The Power System, Tracy Nakamura Toups Jan 2011

Working Active Power, Reflected Active Power, And Detrimental Active Power In The Power System, Tracy Nakamura Toups

LSU Master's Theses

Study of decomposition of the active power into components with deeper economical meanings, namely working active power, reflected active power, and detrimental active power is the subject of the thesis. The decomposition of active power will be based on the Current’s Physical Component (CPC) Theory. Working active power is equivalent to useful power that is the rate of energy used to do work, such as mechanical power. Reflected active power is the rate of energy transfer that the load sends back to the supply which dissipates off the supply resistance. This reflected active power is not taken into account on …


A Study Of The Scale-Invariant Feature Transform On A Parallel Pipeline, Phaneendra Vinukonda Jan 2011

A Study Of The Scale-Invariant Feature Transform On A Parallel Pipeline, Phaneendra Vinukonda

LSU Master's Theses

 Untitled Page

In this thesis we study the running of the Scale Invariant Feature Transform (SIFT) algorithm on a pipelined computational platform. The SIFT algorithm is one of the most widely used methods for image feature extraction.

We develop a tile based template for running SIFT that facilitates the analysis while abstracting away lower-level details. We formalize the computational pipeline and the time to execute any algorithm on it based on the relative times taken by the pipeline stages. In the context of the SIFT algorithm, this reduces the time to that of running the entire image through a …


Surface Parameterization Over Regular Domains, Shenghua Wan Jan 2011

Surface Parameterization Over Regular Domains, Shenghua Wan

LSU Master's Theses

Surface parameterization has been widely studied and it has been playing a critical role in many geometric processing tasks in graphics, computer-aided design, visualization, vision, physical simulation and etc. Regular domains, such as polycubes, are favored due to their structural regularity and geometric simplicity. This thesis focuses on studying the surface parameterization over regular domains, i.e. polycubes, and develops effective computation algorithms. Firstly, the motivation for surface parameterization and polycube mapping is introduced. Secondly, we briefly review existing surface parameterization techniques, especially for extensively studied parameterization algorithms for topological disk surfaces and parameterizations over regular domains for closed surfaces. Then …


Design, Fabrication And Characterization Of A New Wind Tunnel Facility – Linear Cascade With A Wake Simulator, Jean-Philippe Junca-Laplace Jan 2011

Design, Fabrication And Characterization Of A New Wind Tunnel Facility – Linear Cascade With A Wake Simulator, Jean-Philippe Junca-Laplace

LSU Master's Theses

A new wind tunnel has been designed and constructed at the LSU Mechanical Engineering Laboratories. The objective was to design a versatile test facility, suitable for a wide range of experimental measurements on turbine blades. The future study will investigate the impact of unsteady inflow conditions on film cooling performance. More specifically, it will study how the unsteady flow due to the upstream passing wakes coming from the front row vane affects the film cooling performances on the turbine blades. The test section consists of a four passage linear cascade composed of three full blades and two shaped wall blades. …


Environmental Factors Impacting Coastal Beach Health, Kevin Michael Chenier Jan 2011

Environmental Factors Impacting Coastal Beach Health, Kevin Michael Chenier

LSU Master's Theses

The objectives of this research were to 1) determine the variability of fecal-indicator bacteria in Gulf of Mexico marine waters, 2) determine the effect of environmental variables on enterococci concentrations, 3) determine if beach sand at Holly Beach, LA was capable of acting as a reservoir for fecal-indicator bacteria, and 4) determine if a model could be developed to reduce the time it takes to issue a beach swim advisory. Fecal-indicator bacteria concentrations varied from year to year in historical data collected from a Gulf Coast beach. Afternoon fecal-indicator bacteria concentrations were consistently lower than morning concentrations, demonstrating daily variability. …


Gas Turbine Blade Tip And Near Tip Heat Transfer With Film Cooling, Gregory Kramer Jan 2011

Gas Turbine Blade Tip And Near Tip Heat Transfer With Film Cooling, Gregory Kramer

LSU Master's Theses

Gas turbine blade tips experience very high thermal loads due to high temperature combustion gases and tip leakage flows. This leads to the tip region being very susceptible to experiencing failures. To better understand these effects, experiments were performed in a suction-type low speed wind tunnel cascade to determine heat transfer coefficients and film cooling effectiveness distributions on a highly-loaded 2-D gas turbine blade model in the tip and near-tip regions. The blade shape was generated to match the pressure coefficients of the operating turbine blade design. The model featured multiple tip and pressure side film cooling holes and a …


Measurement Of Spatial Variation Of Density Of Compacted Powder Using Synchrotron Microtomography, Yi Yang Jan 2011

Measurement Of Spatial Variation Of Density Of Compacted Powder Using Synchrotron Microtomography, Yi Yang

LSU Master's Theses

This research considers density change in powder metallurgy when compacting a powder blend in a die. In order to provide insights into particle behavior during compaction, atomized aluminum powders with an average particle size of 100 µm were used in two different compaction configurations. The compaction dies are cylindrical in shape: compaction configuration I displays an upper punch, a die, a lower punch, and a spacer. Compaction configuration II displays an upper punch, two dies, a lower punch, and a spacer with different geometry. The Synchrotron Microtomography scans were conducted on both compaction configurations. For compaction configuration I, the scan …


Small Footprint High Flow Rate Microdevice For Rare Target Cell Capture, Taehyun Park Jan 2011

Small Footprint High Flow Rate Microdevice For Rare Target Cell Capture, Taehyun Park

LSU Doctoral Dissertations

A novel high flow rate cell capture design was introduced to overcome the limitations of the current technologies or methods for rare target cell capture. Even though the rare target cell capture using BioMEMS technology has great potential for cancer diagnosis, previous rare cell capture research could not overcome the limitations of low flow rate or low recovery rate. Rare cell research requires precise sample preparation for accurate results. A new method of preparation for a single or a precise number of target cell was introduced. Current sample preparation methods which are not suitable for rare cell research, such as …


Lqg/Ltr Control Of Induction Motor, Girish Arvind Yajurvedi Jan 2011

Lqg/Ltr Control Of Induction Motor, Girish Arvind Yajurvedi

LSU Master's Theses

Induction motors are the most rugged electrical equipment which are widely used in the industry. Owing to the non-linearity in its behaviour, it is not a trivial problem to solve and hence we are interested in using it as a control platform. Through several decades of research a wide number of control schemes have been developed for implementing the closed loop control. Based upon the merits and demerits of various schemes we choose a control scheme called the indirect vector control of Induction motor. Using the electrical dynamics of the motor model we design a LQG/LTR controller. We employ a …