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Full-Text Articles in Engineering

Modeling The Effect Of Gusty Hurricane Wind Force On Vehicles Using The Lsu Driving Simulator, Jose Manuel Rodriguez Jan 2014

Modeling The Effect Of Gusty Hurricane Wind Force On Vehicles Using The Lsu Driving Simulator, Jose Manuel Rodriguez

LSU Master's Theses

While traffic planning is important for developing a hurricane evacuation plan, vehicle performance on the roads during extreme weather conditions is critical to the success of the planning process. This study was designed to lay a foundation for modeling driving behavior and vehicle performance as an assessment tool in the decision making process for planning evacuation routes during hurricane and tropical storms. The study explores how the parameters of a driving simulator could be modified to reproduce wind loadings experienced by three vehicle types (a passenger car, an ambulance, and a bus) during gusty hurricane winds, through manipulation of appropriate …


Biogeochemical Controls On Biodegradation Of Mc252 Crude Oil In Coastal Wetland Systems, Matthew Paul Rodrigue Jan 2014

Biogeochemical Controls On Biodegradation Of Mc252 Crude Oil In Coastal Wetland Systems, Matthew Paul Rodrigue

LSU Master's Theses

Weathering of MC252 oil from the Deepwater Horizon oil spill is taking place in coastal Louisiana marsh and mangrove wetland systems. Alkylated phenanthrenes and dibenzothiophenes, which are the most prominent PAHs found at MC252 contaminated sites, are weathering at rates up to 5% per year relative to alkylated chrysenes 3 years after initial oiling. Flux chambers at marsh locations trapped CO2 that exhibited δ13C signatures lower than indigenous organic matter signifying hydrocarbon mineralization to CO2. Weathering rates at each of these locations are heavily influenced by the biogeochemistry of the surrounding environment. High-resolution nutrient profiles were obtained at different locations …


Fabrication And Enhancement Of Aluminum-Based Microchannel Devices, Paul Joseph Hymel Jan 2014

Fabrication And Enhancement Of Aluminum-Based Microchannel Devices, Paul Joseph Hymel

LSU Master's Theses

Microscale molding replication and transient liquid phase (TLP) bonding were used to fabricate Al-based microchannel heat exchangers (MHEs) and micro gas chromatograph (mGC) columns. Metal-based microchannel heat exchangers often experience corrosion as a result of their operating conditions. To address this problem, an internal anodization method was developed in Al microtubes by pulsing the flow of electrolyte through a microtube when the current dropped below a set value. The anodic aluminum oxide (AAO) films were characterized by scanning electron microscopy (SEM), focused ion beam (FIB) cross sections, and X-ray energy dispersive spectroscopy (EDS) to determine their growth rate and morphology. …


Evaluation Of Different Harvesting And Storage Practices: Sweet Sorghum And Energycane, Ana Lucia Amaya Arroyave Jan 2014

Evaluation Of Different Harvesting And Storage Practices: Sweet Sorghum And Energycane, Ana Lucia Amaya Arroyave

LSU Master's Theses

Two attractive potential feed stocks for biofuel production are energycane and sweet sorghum due to the environmental adaptability, sugars concentration and yield. Evaluation and development of harvesting, transportation and storage practices is critical for bringing the production of these crops to industrial levels. This research aims to analyze the supply system of energy crops and evaluate the effect of different harvesting and storage in the yields of the feedstock and the efficiencies of the processes. Harvesting trials were conducted at St. Gabriel, LA for evaluating the feasibility of using energy crops as inputs for ethanol production. The parameters that were …


Biogeochemical Controls On Fate Of Subsurface Oiled Sands On A Coastal Headland Beach, Autumn Anastasia Westrick Jan 2014

Biogeochemical Controls On Fate Of Subsurface Oiled Sands On A Coastal Headland Beach, Autumn Anastasia Westrick

LSU Master's Theses

The fate of subsurface oiled sands collected from Fourchon Beach in Louisiana were determined while modifying biogeochemical controls on the degradation of PAHs. Groundwater on the beach has intrinsically low dissolved oxygen concentrations, which may limit natural biodegradation of the crude oil components. The intent of this research was to characterize the biogeochemical properties and degradability of oiled sands (with >10% of pore filled with MC252 oil) using a combination of laboratory flow-through reactor studies, field measurements and time-series microelectrode profiles of down-flow and cross flow geometries. Reactor experiments indicate that optimal conditions for substantial oil degradation are aerobic under …


Application Of Tubular Crossflow Microfiltration In Harvesting Microalgae, Mostafa Khademi Jan 2014

Application Of Tubular Crossflow Microfiltration In Harvesting Microalgae, Mostafa Khademi

LSU Master's Theses

Separation of microalgal cells from culture medium is a challenging phase of algal production. Application of microfiltration as Stage 1 harvesting technology to pre-concentrate algal suspension from 0.2 g-dry/L to 10 g-dry/L (1% solids) prior to the final dewatering stage by centrifugation (Stage 2) was studied in this research. A bench-scale filtration setup with three tubular crossflow membrane modules (pore sizes: 0.05 µm, 0.1 µm, 0.5µm) equipped with data acquisition systems was constructed. In phase-1 experiments, the influence of algal species and the size of particles in the culture media on the filterability of microalgae were studied. It was found …


Mechanical And Thermal Properties Of Fly Ash-Based Geopolymer Cement, Fenghong Fan Jan 2014

Mechanical And Thermal Properties Of Fly Ash-Based Geopolymer Cement, Fenghong Fan

LSU Master's Theses

The geopolymer concrete is a more durable and green material with less CO2 emission and less energy consuming as compared with the widely used Portland cement (PC) concrete. In this thesis, an experimental study of the thermo-mechanical properties of a cement prepared using a class F fly ash and three different alkali-activators (NaOH activator, NaOH and Na2SiO3 mixture activator, and KOH and Na2SiO3 mixture activator) is presented. The mechanical properties, including the compressive strength, shrinkage, weight loss, and chemical composition, are investigated utilizing several key tools, such as X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM), and Energy Dispersive X-ray Spectroscopy …


Integration Of Network Protector Relays On Downtown Distribution Networks With Penetration Of Renewable Energy, Nigel Ramon Jordan Jan 2014

Integration Of Network Protector Relays On Downtown Distribution Networks With Penetration Of Renewable Energy, Nigel Ramon Jordan

LSU Master's Theses

The demand and use of renewable energy sources such as solar panels is steadily increasing in today’s world. Renewable energy sources in distribution networks effectively reduce the amount of load consumed by customers. Renewable energy sources are also a solution to many environmental concerns. However, when these sources of energy are added to downtown networks they interfere with the normal operation of the protective relays and impose challenges such as unexpected tripping of network protector relays. In this paper, the effects of network protector relay operation is studied as a function of increasing photovoltaic (PV) penetration within the secondary grid …


Ethical Hacking Using Penetration Testing, Bharath Kumar Koopari Roopkumar Jan 2014

Ethical Hacking Using Penetration Testing, Bharath Kumar Koopari Roopkumar

LSU Master's Theses

This thesis provides details of the hardware architecture and the software scripting, which are employed to demonstrate penetration testing in a laboratory setup. The architecture depicts an organizational computing asset or an environment.¬¬¬ With the increasing number of cyber-attacks throughout the world, the network security is becoming an important issue. This has motivated a large number of “ethical hackers” to indulge and develop methodologies and scripts to defend against the security attacks. As it is too onerous to maintain and monitor attacks on individual hardware and software in an organization, the demand for the new ways to manage security systems …


Efficient Dense 3d Reconstruction Using Image Pairs, Padmapriya Ravi Jan 2014

Efficient Dense 3d Reconstruction Using Image Pairs, Padmapriya Ravi

LSU Master's Theses

The 3D reconstruction of a scene from 2D images is an important topic in the _x000C_eld of Computer Vision due to the high demand in various applications such as gaming, animations, face recognition, parts inspections, etc. The accuracy of a 3D reconstruction is highly dependent on the accuracy of the correspondence matching between the images. For the purpose of high accuracy of 3D reconstruction system using just two images of the scene, it is important to _x000C_nd accurate correspondence between the image pairs. In this thesis, we implement an accurate 3D reconstruction system from two images of the scene at …


Graphical Models In Characterizing The Dependency Relationship In Wireless Networks And Social Networks, Phuoc Doan Huu Vu Jan 2014

Graphical Models In Characterizing The Dependency Relationship In Wireless Networks And Social Networks, Phuoc Doan Huu Vu

LSU Master's Theses

Semi-Markov processes have become increasingly important in probability and statistical modeling, which have found applications in traffic analysis, reliability and maintenance, survival analysis, performance evaluation, biology, DNA analysis, risk processes, insurance and finance, earthquake modeling, etc. In the first part of this thesis, our focus is on applying semi-Markov processes to modeling the on-off duty cycles of different nodes in wireless networks. More specifically, we are interested in restoration of statistics of individual occupancy patterns of specific users based on wireless RF observation traces. In particular, we present a novel approach to finding the statistics of several operations, namely down-sampling, …


Minimization Of Transportation, Installation And Maintenance Operations Costs For Offshore Wind Turbines, Tasnim Ibn Faiz Jan 2014

Minimization Of Transportation, Installation And Maintenance Operations Costs For Offshore Wind Turbines, Tasnim Ibn Faiz

LSU Master's Theses

Although it is a sustainable source and there is abundant potential for energy, cost of energy generated from offshore wind is still high compared to other sustainable energy sources. Apart from the manufacturing cost of turbines, cost of energy is significantly affected by costs of transportation and installation operations of wind turbines and maintenance operations of turbine components. Through optimum selection of decision variables, such as turbine installation method and rated power output of each turbine, cost of transportation and installation operations can be minimized. The first model in this study investigates the impact of these decision variables and effect …


Analyses Of Online Monitoring Signals For A Gmaw Process Before And After Improvement, Aniruddha Joshi Jan 2014

Analyses Of Online Monitoring Signals For A Gmaw Process Before And After Improvement, Aniruddha Joshi

LSU Master's Theses

The ability to detect the onset of welding instability is a very powerful tool in welding process monitoring and control. Toward this goal, this study investigates a gas metal arc welding (GMAW) process by analyzing online monitoring signals. Two separate data sets are obtained from the process, which correspond to (a) a stable process after improvement and (b) a relatively unstable process which tends to exhibit spatter and poor weld bead geometry. Voltage, current, wire-feeding speed and line speed signals for both data sets are analysed and features are extracted from the raw signals using different signal processing techniques. Specifically, …


Field And Numerical Investigation Of Wave Power And Shoreline Retreat In Terrebonne Bay, Southern Louisiana, Kyle Ryan Parker Jan 2014

Field And Numerical Investigation Of Wave Power And Shoreline Retreat In Terrebonne Bay, Southern Louisiana, Kyle Ryan Parker

LSU Master's Theses

The marshland in southern Louisiana is a vital resource that many people and wildlife depend on. Terrebonne Bay was chosen for this research because it has experienced one of the largest wetland loss rates among Louisiana estuaries. Investigations of wave power and shoreline retreat rate could provide decision makers with a better understanding of the contributing wave force responsible for local shoreline retreat. A strong relationship has been shown to exist between wave power and shoreline retreat [Schwimmer (2001) and Marani et al. (2011)]. Whether or not this strong relationship exists in Terrebonne Bay is the subject of this research. …


Effect Of Forced Flow Oscillation On Churn And Annular Flow In Vertical Wellbores, Catalina Posada Jan 2014

Effect Of Forced Flow Oscillation On Churn And Annular Flow In Vertical Wellbores, Catalina Posada

LSU Master's Theses

Producing oil and gas from marginal hydrocarbon reservoirs and mature fields present particular challenges. One of the challenges for these types of fields is flow instability. Pipeline risers and artificial gas-lift systems experience instabilities, which cause significant reductions in production among others operational drawbacks. Different types of instabilities (static and dynamic) have been identified affecting those systems. However, there is still a lack of systematic investigations associated with the understanding of dynamic instabilities (periodic oscillations) and their impact in production systems. A systematic investigation of the effects of periodic forced oscillations on gas-liquid flows in a 42 m (140-ft) long, …


Distributed Stabilization Of Nonlinear Multi-Agent Systems, Jianming Zhou Jan 2014

Distributed Stabilization Of Nonlinear Multi-Agent Systems, Jianming Zhou

LSU Master's Theses

The study of multi-agent systems (MASs) is focused on systems in which many autonomous agents interact and operate within a limited communication environment. The general goal of the MAS research is to design interconnection control laws such that all the dynamic agents in the group are synchronized to a desired common trajectory by exchanging information with adjacent agents over certain constrained communication networks. Based on the review and modification of existing results concerning the consensus control of linear heterogeneous MASs in Moreau (2004) [21], Scardovi and Sepulchre (2009) [25], Wieland et al (2011) [30], and Alvergue et al. (2013) [1], …


Evaluating The Impact Of Lean On Employee Ergonomics, Safety, And Job Satisfaction In Manufacturing, Amanda Morse Jan 2014

Evaluating The Impact Of Lean On Employee Ergonomics, Safety, And Job Satisfaction In Manufacturing, Amanda Morse

LSU Master's Theses

The goal of this study was to explore the proposed relationship between employee satisfaction, ergonomics, and safety while implementing a Kaizen event. In order to address this goal, two Kaizen events (K1 and K2) were conducted in a heavy equipment manufacturing plant. Before and after both events, levels of employee satisfaction were documented for Kaizen and Non-Kaizen (NK) participants using the Job Diagnostic Survey (JDS). The objective of the first event (K1) was to improve the efficiency of the task of torqueing the rear axle bolts in Station #1- skid assembly. The K1 methodology followed a traditional Kaizen structure, enhanced …


Image-Based Pore-Scale Modeling Of Inertial Flow In Porous Media And Propped Fractures, Yijie Shen Jan 2014

Image-Based Pore-Scale Modeling Of Inertial Flow In Porous Media And Propped Fractures, Yijie Shen

LSU Doctoral Dissertations

Non-Darcy flow is often observed near wellbores and in hydraulic fractures where relatively high velocities occur. Quantifying additional pressure drop caused by non-Darcy flow and fundamentally understanding the pore-scale inertial flow is important to oil and gas production in hydraulic fractures. Image-based pore-scale modeling is a powerful approach to obtain macroscopic transport properties of porous media, which are traditionally obtained from experiments and understand the relationship between fluid dynamics with complex pore geometries. In image-based modeling, flow simulations are conducted based on pore structures of real porous media from X-ray computed tomographic images. Rigorous pore-scale finite element modeling using unstructured …


Bayesian Saltwater Intrusion Prediction And Remediation Design Under Uncertainty, Nima Chitsazan Jan 2014

Bayesian Saltwater Intrusion Prediction And Remediation Design Under Uncertainty, Nima Chitsazan

LSU Doctoral Dissertations

Groundwater resources are vital for sustainable economic and demographic developments. Reliable prediction of groundwater head and contaminant transport is necessary for sustainable management of the groundwater resources. However, the groundwater simulation models are subjected to uncertainty in their predictions. The goals of this research are to: (1) quantify the uncertainty in the groundwater model predictions and (2) investigate the impact of the quantified uncertainty on the aquifer remediation designs. To pursue the first goal, this study generalizes the Bayesian model averaging (BMA) method and introduces the hierarchical Bayesian model averaging (HBMA) method that segregates and prioritizes sources of uncertainty in …


Image Enhancement Methods And Applications In Computational Photography, Qinchun Qian Jan 2014

Image Enhancement Methods And Applications In Computational Photography, Qinchun Qian

LSU Doctoral Dissertations

Computational photography is currently a rapidly developing and cutting-edge topic in applied optics, image sensors and image processing fields to go beyond the limitations of traditional photography. The innovations of computational photography allow the photographer not only merely to take an image, but also, more importantly, to perform computations on the captured image data. Good examples of these innovations include high dynamic range imaging, focus stacking, super-resolution, motion deblurring and so on. Although extensive work has been done to explore image enhancement techniques in each subfield of computational photography, attention has seldom been given to study of the image enhancement …


Development Of Remote Sensing Assisted Water Quality Nowcasting And Forecasting Models For Coastal Beaches, Zaihong Zhang Jan 2014

Development Of Remote Sensing Assisted Water Quality Nowcasting And Forecasting Models For Coastal Beaches, Zaihong Zhang

LSU Doctoral Dissertations

A remote sensing assisted water quality modeling framework is developed in this dissertation for nowcasting and forecasting recreational water quality of Holly Beach in Louisiana, USA. The modeling framework is composed of four models/systems: (1) an Artificial Neural Network (ANN) model (Model 1) and an US EPA Virtual Beach (VB) Program-based model for predicting early morning enterococci (ENT) levels in beach waters; (2) an ANN model (Model 2) and an VB model for predicting early morning Fecal Coliform (FC) levels in beach waters; (3) a remote sensing assisted modeling system (Model 3) for predicting near real time ENT levels during …


Damage Prediction Of Low-Rise Buildings Under Hurricane Winds, Fang Pan Jan 2014

Damage Prediction Of Low-Rise Buildings Under Hurricane Winds, Fang Pan

LSU Doctoral Dissertations

Low-rise buildings are defined as the buildings with a mean roof height less than the least horizontal dimension and less than 18.3 m in ASCE 7-10. They represent the majority of commercial, residential, and industrial buildings. Approximate 90% of the existing low-rise residential buildings are constructed as wood light-frame buildings that are not fully engineered and thus more vulnerable to extreme wind pressures, wind borne debris and rain water intrusion. The resulting hurricane-induced economic loss is primarily attributed to the insufficient performance of building envelope instead of the catastrophic failure of their main structural system for Category 1 to 4 …


The Effects Of Asymmetric Micro Ratchets On Pool Boiling Performance, Lance Austin Brumfield Jan 2014

The Effects Of Asymmetric Micro Ratchets On Pool Boiling Performance, Lance Austin Brumfield

LSU Doctoral Dissertations

Nucleate boiling is an attractive method for achieving high heat flux at low superheat temperatures. It is frequently used for industrial applications such as heat exchangers and is being considered to cool advanced central processing units (CPU) which produce heat fluxes on the order of 1 MW/m2 and are becoming increasingly less efficient to cool via forced conduction of air. The issue with implementing nucleate boiling as a cooling mechanism lies in the difficulty of quantifying the numerous and complex mechanisms which control the process. A comprehensive nucleate boiling model has yet to be formulated and will be required in …


Advanced Statistical Signal Processing Methods In Sensing, Detection, And Estimation For Communication Applications, Hongting Zhang Jan 2014

Advanced Statistical Signal Processing Methods In Sensing, Detection, And Estimation For Communication Applications, Hongting Zhang

LSU Doctoral Dissertations

The applications of wireless communications and digital signal processing have dramatically changed the way we live, work, and learn over decades. The requirement of higher throughput and ubiquitous connectivity for wireless communication systems has become prevalent nowadays. Signal sensing, detection and estimation have 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 sensing, detection and estimation techniques are still in demand since there emerge more and more practical applications which rely on them. In this dissertation work, …


Piezoelectric Based Energy Harvesting On Low Frequency Vibrations Of Civil Infrastructures, Ye Zhang Jan 2014

Piezoelectric Based Energy Harvesting On Low Frequency Vibrations Of Civil Infrastructures, Ye Zhang

LSU Doctoral Dissertations

Piezoelectric-based energy harvesting is an efficient way to convert ambient vibration energy into usable electric energy. The piezoelectric harvester can work as a sustainable and green power source for different electric devices such as sensors and implanted medical devices. However, its application on civil infrastructures has not been fully studied yet. This dissertation aimed to study and improve the piezoelectric-based energy harvesting on civil infrastructures, especially on bridge structures. To reach the objective, a more accurate model for piezoelectric composite beams was built first, which can be adopted for the modeling of different kinds of energy harvesters. The model includes …


Analysis Of Hydrodynamic Drag Forces Acting On Suspended Fine Particle In Porous Media, Seyed Amin Mirsaeidi Farahani Jan 2014

Analysis Of Hydrodynamic Drag Forces Acting On Suspended Fine Particle In Porous Media, Seyed Amin Mirsaeidi Farahani

LSU Doctoral Dissertations

An important class of flow and transport problems occurring in porous media involves the interactions between suspended fine particles and the moving fluid at Stokes limit. Historically, due to the complicated geometries of porous media, researchers have had to resort to simplifying assumptions to conceptualize the underlying physics. However, the advent of high performance computing, in recent decades, has made it possible to vigorously investigate this problem at the streamline scale level. In this work, the flow problem is solved by means of a finite-element model. The simulations results are used to compute the drag forces experienced by suspended fine …


Power System Differential Model With Application To Grid Dynamic Simulation, Boyu Wang Jan 2014

Power System Differential Model With Application To Grid Dynamic Simulation, Boyu Wang

LSU Master's Theses

Nonlinearity of power system is always one of the difficulties when dealing with dynamic simulation of power systems. Solving differential-algebraic equations representing power systems are difficult without losing nonlinearity, especially for large power systems. This thesis shows an alternative method to solve nonlinear dynamical power system by producing a purely differential representation of the power systems. This new representation converts the algebraic equations to differential equations in order to have an absolute differential system. By using Runge-Kutta algorithm to solve this differential system, the results of the power system simulations are compared to trapezoidal integration algorithm commonly used to solve …


Innovative Heat Transfer Augmentation Techniques In Mechanical Face Seal, Nian Xiao Jan 2014

Innovative Heat Transfer Augmentation Techniques In Mechanical Face Seal, Nian Xiao

LSU Doctoral Dissertations

Excessive heat generated at the face seal contact interface has been recognized as one of main causes of failure of mechanical seals. In the past few decades various efforts have been attempted to remove heat from the contact interface uniformly in order to reduce the interfacial temperature, eliminate thermally-induced failure, and thus increase the life of a mechanical seal. Two innovative heat transfer augmentation techniques - surface texturing and built-in phase change device - have been developed in our laboratory to effectively enhance the heat transfer in mechanical face seal. Surface texturing can increase the surface area, change the near …


Energy Dissipation And Entropy Generation During The Fatigue Degradation: Application To Health Monitoring Of Composites, Ali Kahirdeh Jan 2014

Energy Dissipation And Entropy Generation During The Fatigue Degradation: Application To Health Monitoring Of Composites, Ali Kahirdeh

LSU Doctoral Dissertations

In this dissertation, an experimental approach for characterizing energy dissipation and degradation evolution in a woven Epoxy/Glass (G10/FR4) laminate subjected to fully reversed bending fatigue test is presented. Infrared thermography and acoustic emission are utilized to characterize the degradation progression. The results show similar evolutionary response indicating the presence of three degradation stages. The effect of the surface cooling on the fatigue life of the laminates is investigated both experimentally and analytically. The results show that the life of the laminate is highly dependent on the temperature and that surface cooling can significantly increase the fatigue life of the laminate. …


Cyber-Physical Security Strategies, Sarah Davis Jan 2014

Cyber-Physical Security Strategies, Sarah Davis

LSU Master's Theses

Cyber-physical security describes the protection of systems with close relationships between computational functions and physical ones and addresses the issue of vulnerability to attack through both cyber and physical avenues. This describes systems in a wide variety of functions, many crucial to the function of modern society, making their security of paramount importance. The development of secure system design and attack detection strategies for each potential avenue of attack is needed to combat malicious attacks. This thesis will provide an overview of the approaches to securing different aspect of cyber-physical systems. The cyber element can be designed to better prevent …