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Articles 1111 - 1140 of 2820
Full-Text Articles in Engineering
Operational Impact Of Shadow Evacuation On Regional Road Networks During Short-Notice Emergency Evacuations, Efe Emre Tuncer
Operational Impact Of Shadow Evacuation On Regional Road Networks During Short-Notice Emergency Evacuations, Efe Emre Tuncer
LSU Master's Theses
As part of evacuation planning, development of effective tactical and operational strategies are essential to safely and efficiently mobilize the public away from the threat. Evacuations are classified by the time between notification and the anticipated arrival of the threat which can be categorized as short, or no-notice emergencies. Emergencies involve the computation of the time required to evacuate the area of risk, which is the time to clear a radius of up to about 10-miles around the nuclear power plant, known as the emergency planning zone (EPZ). These evacuation time estimates (ETE) also account for the evacuation of the …
Evaluating Classifiers' Optimal Performances Over A Range Of Misclassification Costs By Using Cost-Sensitive Classification, Ramy Al-Saffar
Evaluating Classifiers' Optimal Performances Over A Range Of Misclassification Costs By Using Cost-Sensitive Classification, Ramy Al-Saffar
LSU Master's Theses
We believe that using the classification accuracy is not enough to evaluate the performances of classification algorithms. It can be misleading due to overlooking an important element which is the cost if classification is inaccurate. Furthermore, the Receiver Operational Characteristic (ROC) is one of the most popular graphs used to evaluate classifiers performances. However, one of the biggest ROC’s shortcomings is the assumption of equal costs for all misclassified data. Therefore, our goal is to reduce the total cost of decision making by selecting the classifier that has the least total misclassification cost. Nevertheless, the exact misclassification cost is usually …
Magnetic Gradient Drilling, Garrett Lowry Nielsen
Magnetic Gradient Drilling, Garrett Lowry Nielsen
LSU Master's Theses
The drilling industry has always had difficulties with staying within the mud weight window. The problems associated with failure to stay within the mud weight window include uncontrolled influxes and wellbore collapse on the low pressure side of the window, and fluid losses and wellbore damage on the high pressure side of the window. When the risk for getting outside of this mud window becomes too great, casing must be set in order to isolate formations from each other. If too many strings of casing are set, or if the damage from getting out of the mud weight window is …
Enhanced Grain Partitioning Of X-Ray Microtomography Segmented Images, Nicholas C. Skrivanos Ii
Enhanced Grain Partitioning Of X-Ray Microtomography Segmented Images, Nicholas C. Skrivanos Ii
LSU Master's Theses
In the field of petroleum engineering, rock samples are often taken from wells during the drilling process. Grain partitioning of digital three-dimensional microtomography segmented images obtained from these samples provides valuable in-situ properties and statistics that allow for accurate particle and structure characterization. This information can be used directly in detailed production and reservoir analysis, and can also be used to generate realistic packing models for advanced simulation. Additionally, the partitioned image can be used as a building block for realistic hydraulic fracture modeling. This technology has applications in other fields as well, such as core analysis in soil sciences …
Effect Of Pipe Rotation On Casing Pressure Within Mpd Applications, Zahrah Ahmed Al Marhoon
Effect Of Pipe Rotation On Casing Pressure Within Mpd Applications, Zahrah Ahmed Al Marhoon
LSU Master's Theses
Well control is one of the most crucial sectors in drilling engineering. Human lives and safety depend on the correct execution of the engineering design. Managed Pressure Drilling (MPD) is a new technology that has recently emerged in the oil and gas industry. It has special well control abilities supported by the RCD to continue drilling or carry operations that involve pipe rotation, while circulating out a gas kick. This thesis examines the effect of pipe rotation on casing pressure profiles within MPD kick circulation application. The analysis was carried on real scale kick experiments. These experiments were carried in …
The Tensile Root Strength Of Emergent Coastal Macrophytes, Lauris Olivia Hollis
The Tensile Root Strength Of Emergent Coastal Macrophytes, Lauris Olivia Hollis
LSU Doctoral Dissertations
Spartina patens is a dominant emergent macrophyte in fresh, intermediate, and brackish marshes along the Atlantic and Gulf coasts of United States where its biomechanical properties are a key component of wetland health and resilience. Its root biomass and tensile root strength are essential for anchorage, erosion protection, and are important determinants of soil strength. Nutrients and the herbicide atrazine are suspected of negatively impacting this wetland plant and others. The objectives of this study were to: 1) ascertain the tensile root strength of five emergent coastal macrophytes in coastal estuaries, and 2) test the effects of nutrient addition, atrazine …
Numerical Simulation Of Uncoiling And Roller Leveling Processes From Steel Coils, Yufei Xiong
Numerical Simulation Of Uncoiling And Roller Leveling Processes From Steel Coils, Yufei Xiong
LSU Master's Theses
Uncoiling and roller leveling play an important role in pipe forming because it is prerequisite to make products with good quality. Uncoiling and roller leveling are used to reduce undesired characteristics such as imperfections in sheet flatness and residual stress. Considering residual stress in steel coil which has been ignored to date, a simplified coiling process is combined with uncoiling and leveling processes to investigate their effects on residual stress and curvature. The objective of this thesis research focuses particularly on studying the influence of coil diameter, uncoiling direction and leveling settings on residual stress and residual strip curvature after …
Microfluidic Technology And Application In Urinal Analysis, Jiwen Xiang
Microfluidic Technology And Application In Urinal Analysis, Jiwen Xiang
LSU Doctoral Dissertations
Microfluidic technology offers numerous advantages in minimizing and integrating the traditional assays. However, the lack of efficient control components of the microfluidic systems has been hindering the widely commercialization of the technology. The research work in this dissertation focused on the development of effective control components for microfluidic applications.
A linear peristaltic pump was firstly designed, fabricated, and tested for conventional microfluidics by synchronously compressing the microfluidic channel with a miniature cam-follower system in Chapter 2. The miniature cam-follower system and microfluidic chip was prototyped using three-dimensional (3D) printing technology and soft lithography technology. Results from experimental test showed that …
Preparation And Characterization Of Nanocellulose And Its Application In Composite Materials, Xiuxuan Sun
Preparation And Characterization Of Nanocellulose And Its Application In Composite Materials, Xiuxuan Sun
LSU Doctoral Dissertations
Transparent cellulose films from 2,2,6,6-tetramethylpiperidine-1-oxyl radical oxidized cellulose nanocrystals (TOCNs) and 64 wt% sulfuric acid treated cellulose nanocrystals (SACNs) were prepared from bleached wood pulps. Film morphology, optical, mechanical, thermal, and surface wettability properties were characterized and compared. The results showed that TOCNs and SACNs had different average length, diameter, and aspect ratio.
The effect of cellulose nanofibers (CNFs) on flow, hydration, morphology, and strength of oil well cement (OWC) was investigated using a range of spectroscopic methods coupled with rheological modeling and strength analysis. The Vom-Berg model showed the best fitting result of the rheology data. The addition of …
Investigation Of Morphological Changes In Small Coastal Rivers During Flood, Tanzina Afrin
Investigation Of Morphological Changes In Small Coastal Rivers During Flood, Tanzina Afrin
LSU Master's Theses
The delivery of fluvial sediment to coastal margins is one of the major concerns for river and coastal morphodynamics. Relevant research has primarily focused on large rivers that transport substantial sediment load and thus are responsible for building deltaic landscapes. However, less research is concentrated on small coastal rivers. A need exists to better understand the sediment dynamics in small coastal rivers that have different backwater regimes than their larger counterparts. The main objective of this research was to examine the influence of backwater on the morphodynamics of a small coastal meandering river during a large flood event. The investigation …
A 2-D Finite Element Modeling And Simulation Of 3-Roll Forming, Wenbo Zhao
A 2-D Finite Element Modeling And Simulation Of 3-Roll Forming, Wenbo Zhao
LSU Master's Theses
Medium to large diameter carbon steel pipes are widely used in various applications such as gas and fluid transportation, tunnels construction and building construction. Based on manufacturing techniques and characteristics, they are mainly categorized into three categories: Seamless pipe, Butt-welded pipe and Spiral pipe. The forming of butt-welded and spiral pipe is often performed by a technique called 3-roller bending. While traditional trial-and-error method is costly, the geometry complexity, along with material nonlinearity makes exact theoretical analysis difficult unless heavy simplified assumptions are made. While the forming parameters in the 3-roller forming process of butt-welded pipe has been studied in …
Image-Based Modeling Of Flow Through Porous Media: Development Of Multiscale Techniques For The Pore Level, Timothy Wayne Thibodeaux
Image-Based Modeling Of Flow Through Porous Media: Development Of Multiscale Techniques For The Pore Level, Timothy Wayne Thibodeaux
LSU Doctoral Dissertations
Increasingly, imaging technology allows porous media problems to be modeled at microscopic and sub-microscopic levels with finer resolution. However, the physical domain size required to be representative of the media prohibits comprehensive micro-scale simulation. A hybrid or multiscale approach is necessary to overcome this challenge. In this work, a technique was developed for determining the characteristic scales of porous materials, and a multiscale modeling methodology was developed to better understand the interaction/dependence of phenomena occurring at different microscopic scales. The multiscale method couples microscopic simulations at the pore and sub-pore scales. Network modeling is a common pore-scale technique which employs …
System Nonlinear Performance Of Low-Rise Buildings Under Database-Assisted Hurricane Loads, Jing He
System Nonlinear Performance Of Low-Rise Buildings Under Database-Assisted Hurricane Loads, Jing He
LSU Doctoral Dissertations
Light-frame wood buildings account for over 95% of all residential structures in the U.S, of which the majority are designed as low-rise buildings. These low-rise residential buildings in the U.S. have performed unsatisfactorily and are the largest source of the damage and fatality during the past extreme wind events. To deepen the understanding and reduce the vulnerability of the infrastructures, the accurate prediction of the hurricane loss has been an urgent need, and the hurricane catastrophe models are developed in response. However, the current hurricane catastrophe models are focused on the economy loss estimation rather than investigating the root causes …
An Evaluation Of The Groundwater Microbial Community's Toluene Biogenesis Potential At A Site In Southeast Louisiana, Michael A. Griffin Jr.
An Evaluation Of The Groundwater Microbial Community's Toluene Biogenesis Potential At A Site In Southeast Louisiana, Michael A. Griffin Jr.
LSU Master's Theses
The broad goal of the research described in this thesis was to better understand the potential for biological toluene production to occur in groundwater at a Superfund Site located in southeast Louisiana. Previous literature reported that bacterial isolates under laboratory test conditions and undefined microbial communities in anaerobic sludge digesters and seasonally stratified lakes can produce toluene biogenically. Most of the research reported on this subject previously, however, has been on systems in Europe and little research has been reported previously on such phenomena in North America.
In the research described here, studies were conducted utilizing groundwater from a Superfund …
Diversionary Behavior During Congestion, Venkata Vamsikrishna Peddisetty
Diversionary Behavior During Congestion, Venkata Vamsikrishna Peddisetty
LSU Master's Theses
Most people in the US prefer to travel on freeways, but when there is congestion they divert onto local routes to avoid travel delay. This study measures the traffic diversion induced by an increase in congestion on I-10 freeway in Baton Rouge during congestion, using a Bluetooth Detection System. The main objective of the study was to identify the difference in the level of congestion on the I-10 between the Mississippi River Bridge and the I-10/I-12 split and the level of congestion on local roads that triggers traffic to divert from the freeway to parallel arterials. Other objectives include measuring …
Simulating The Effects Of Co2 Gas Influx On The Thermodynamic Conditions Inside A Marine Riser Filled With Oil Based Mud, Hassan Al Dawood
Simulating The Effects Of Co2 Gas Influx On The Thermodynamic Conditions Inside A Marine Riser Filled With Oil Based Mud, Hassan Al Dawood
Honors Capstones
No abstract provided.
Microfluidic Pore Model Study On Physical And Geomechanical Factors Influencing Fluid Flow Behavior In Porous Media, Shuang Cao
LSU Doctoral Dissertations
Fluid flow in porous media is a subject of fundamental importance and relevant to numerous engineering applications. The comprehensive description of fluid interaction parameters containing wetting properties, fluid-fluid displacement ratio, and capillary pressure, are inevitably needed. Moreover, the fine-grained sediments’ response to various pore fluids and migration in porous media influences reservoir geomechanical properties and pore clogging is essential to a better understanding of fluids flow behavior.
This dissertation provides a detailed study of physical and geomechanical factors influencing fluids flow behavior in porous media. The two-dimensional micromodel tests have been conducted under a wide selection of fluids flow conditions. …
Multiphase Flow Modeling For Design And Optimization Of A Novel Down-Flow Bubble Column, Mutharasu Lalitha Chockalingam
Multiphase Flow Modeling For Design And Optimization Of A Novel Down-Flow Bubble Column, Mutharasu Lalitha Chockalingam
LSU Doctoral Dissertations
The application of the Euler-Euler framework based Computational Fluid Dynamics (CFD) models for simulating the two-phase gas-liquid bubbly flow in down-flow bubble columns is discussed in detail. Emphasis is given towards the modelling and design optimization of a novel down-flow bubble column. The design features of this novel down-flow bubble column and its advantages over a conventional Plunging Jet down-flow bubble column are discussed briefly. Then, some of the present challenges in simulating a conventional Plunging Jet down-flow bubble column in the Euler-Euler framework is highlighted, and a sigmoid function based drag modification function is implemented to overcome those challenges. …
Multi-Hazard Performance Assessment Of High-Rise Buildings, Jad El Khoury Antoun
Multi-Hazard Performance Assessment Of High-Rise Buildings, Jad El Khoury Antoun
LSU Master's Theses
In the last few decades, there has been an important increase in building high-rise constructions in many cities around the world. Since they offer several benefits in populous areas in terms of space efficiency, economy and sustainability, tower buildings attracted practitioners and researchers to understand better their exclusive behavior and response to natural hazards (e.g., hurricanes, earthquakes). Because of their flexibility and their commonly limited damping, skyscrapers are more susceptible to wind and earthquake actions than low- and mid-rise buildings. Moreover, many locations are prone to multiple hazards; hence, it is important to understand thoroughly the structural behavior of structures …
Surface Enhanced Raman Scattering (Sers) Substrates And Probes, Srismrita Basu
Surface Enhanced Raman Scattering (Sers) Substrates And Probes, Srismrita Basu
LSU Doctoral Dissertations
Raman spectroscopy is a well-known technique for complex molecular detection. In Raman spectrometry, laser beam is focused on a sample to generate a unique "fingerprint" of the molecule. The Raman signal is very weak. To overcome this problem nano rough metallic substrates are fabricated to enhance the signal strength. In clinical applications, remote contact and minimally invasive probes inside the specimen are needed.
This research work is divided in: (1) development of Surface Enhanced Raman Scattering (SERS) substrate using gold coated etched aluminum foil, (2) development of the SERS probe using the aluminum based substrate with a single optical fiber …
New Multi-Resolution Shortest-Path Navigation Techniques Using The Ndvi Imagery, Rui Tian
New Multi-Resolution Shortest-Path Navigation Techniques Using The Ndvi Imagery, Rui Tian
LSU Master's Theses
In this thesis work, we study the visible-light and near-infrared images for practical applications. Different colormaps, contours, or pixel-based indicators can be extracted from these optical images. Among them, normalized difference vegetation index (NDVI) has been widely utilized for applications in vegetation-health monitoring, geological survey, and climate forecast, etc. recently. We extend the use of NDVI for the navigation over the uncharted geographical areas. Henceforth, we propose a new algorithm which is called multi-resolution Dijkstra algorithm to find the approximate shortest paths within the large planar graphs representing the real terrains.
The outline of this thesis is briefed as follows. …
High-Throughput Droplet Barcoding And Automated Image Analysis In Microfluidic Droplet Trapping Array, Manibarathi Vaithiyanathan
High-Throughput Droplet Barcoding And Automated Image Analysis In Microfluidic Droplet Trapping Array, Manibarathi Vaithiyanathan
LSU Master's Theses
Molecularly-targeted therapeutics and personalized medicine have dramatically increased the median survival rate of patients suffering from cancer. However, cellular heterogeneity and the personalized nature of cancer have resulted in the limited success of single drug treatments which has led to the use of multiple therapeutic combinations. This has required the development of new analytical methods capable of multiplexed high-throughput screening (HTS) technologies necessary to identify is single or multi-agent therapies are effective in ex vivo samples like liquid biopsies. Droplet microfluidic devices have garnered significant interest to facilitate high-throughput, single cell analysis of heterogeneous populations. However, these devices are still …
Nonlinear Model-Based Control For Neuromuscular Electrical Stimulation, Ruzhou Yang
Nonlinear Model-Based Control For Neuromuscular Electrical Stimulation, Ruzhou Yang
LSU Doctoral Dissertations
Neuromuscular electrical stimulation (NMES) is a technology where skeletal muscles are externally stimulated by electrodes to help restore functionality to human limbs with motor neuron disorder. This dissertation is concerned with the model-based feedback control of the NMES quadriceps muscle group-knee joint dynamics. A class of nonlinear controllers is presented based on various levels of model structures and uncertainties. The two main control techniques used throughout this work are backstepping control and Lyapunov stability theory.
In the first control strategy, we design a model-based nonlinear control law for the system with the exactly known passive mechanical that ensures asymptotical tracking. …
Mechanistic Modeling Of Nanoparticle-Stabilized Supercritical Co2 Foams And Its Implication In Field-Scale Eor Applications, Doris Patricia Ortiz Maestre
Mechanistic Modeling Of Nanoparticle-Stabilized Supercritical Co2 Foams And Its Implication In Field-Scale Eor Applications, Doris Patricia Ortiz Maestre
LSU Master's Theses
Previous experimental studies show that nanoparticle-stabilized supercritical CO2 foams (or, NP CO2 foams) can be applied as an alternative to surfactant foams, in order to reduce CO2 mobility in gas injection enhanced oil recovery (EOR). These nanoparticles, if chosen correctly, can be an effective foam stabilizer attached at the fluid interface in a wide range of physicochemical conditions.
By using NP CO2 foam experiments available in the literature, this study performs two tasks: (i) presenting how a mechanistic foam model can be used to fit experimental data and determine required model parameters, and (ii) investigating the …
Development Of Artificial Intelligence Approach To Nowcasting And Forecasting Oyster Norovirus Outbreaks Along The U.S. Gulf Coast, Shima Shamkhali Chenar
Development Of Artificial Intelligence Approach To Nowcasting And Forecasting Oyster Norovirus Outbreaks Along The U.S. Gulf Coast, Shima Shamkhali Chenar
LSU Doctoral Dissertations
Oyster norovirus outbreaks pose increasing risks to human health and seafood industry worldwide. This study presents an Artificial Intelligence (AI)-based approach to identifying the primary cause of oyster norovirus outbreaks, nowcasting and forecasting the growing risk of oyster norovirus outbreaks in coastal waters. AI models were developed using Artificial Neural Networks (ANNs) and Genetic Programming (GP) methods and time series of epidemiological and environmental data. Input variable selection techniques, including Random Forests (RF) and Forwards Binary Logistic Regression (FBLR), were used to identify the significant model input variables among six independent environmental predictors including water temperature, solar radiation, gage height, …
A Multi-Scale Approach For Modeling Shock Ignition And Burn Of Granular Hmx, Pratap Thamanna Rao
A Multi-Scale Approach For Modeling Shock Ignition And Burn Of Granular Hmx, Pratap Thamanna Rao
LSU Doctoral Dissertations
Deflagration-to-detonation transition (DDT) in confined, low-density granular HMX (65%-85% Theoretical Maximum Density, TMD) occurs by a complex mechanism that involves compaction shock interactions within the material. Piston driven DDT experiments indicate that detonation is abruptly triggered by the interaction of a strong burn-supported secondary shock and a piston-supported primary (input) shock, where the nature of the interaction depends on initial packing density and primary shock strength. These interactions influence transition by affecting hot-spot formation within the micro-structure during pore collapse. In this study, meso-scale simulations of hot-spot formation in shock loaded granular HMX are used to guide the development of …
Field Investigation And Performance Evaluation Of Interface Bonding Between Pavement Layers, Ramendra N. Das
Field Investigation And Performance Evaluation Of Interface Bonding Between Pavement Layers, Ramendra N. Das
LSU Master's Theses
Proper bonding between pavement layers is essential to provide a monolithic pavement structure that allows distribution of loading over a larger area. Inadequate interface bonding may cause debonding or shear failure at the interface due to the accumulation of concentrated tensile stresses at the bottom of the overlay. Tack coat, a light application of asphaltic cement emulsion is applied on the existing surface to create a strong adhesive bond between pavement layers. The objectives of this study are to investigate the effects of various factors affecting bond strength between hot-mix asphalt (HMA) overlay and underlying pavement layers in the field. …
Sustained Flow Index: A Stochastic Measure Of Freeway Performance, Siavash Shojaat
Sustained Flow Index: A Stochastic Measure Of Freeway Performance, Siavash Shojaat
LSU Doctoral Dissertations
The capacity of a road addresses its quantitative traffic carrying ability. The estimation of capacity as a parameter to assess traffic flow performance on freeway facilities has received considerable attention in the literature. Research into the traffic operation at high volumes reveals that the capacity of freeways is not a fixed number, but rather a random variable. Thus, in a stochastic approach to freeway capacity of estimation, the capacity is treated as a random variable generated from a population of flow observations, stemmed from a certain distribution function. Since the type of capacity distribution function is generally not known with …
Microgrid Energy Management With Flexibility Constraints: A Data-Driven Solution Method, Okan Ciftci
Microgrid Energy Management With Flexibility Constraints: A Data-Driven Solution Method, Okan Ciftci
LSU Master's Theses
Microgrid energy management is a challenging and important problem in modern power systems. Several deterministic and stochastic models have been proposed in the literature for the microgrid energy management problem. However, more accurate models are required to enhance flexibility of the microgrids when accounting for renewable energy and load uncertainties. This thesis proposes key contributions to solve the energy management problem for smart building (or small-scale microgrid). In Chapter 3, a deterministic energy management model is presented taking into account system flexibility requirements. Energy storage systems are deployed to enhance the grid flexibility and ramping capability. The objective function of …
Prevention Of Alkali-Silica Reaction (Asr) In Lightweight Wellbore Cements Containing Silica-Based Microspheres, Dylan Albers
Prevention Of Alkali-Silica Reaction (Asr) In Lightweight Wellbore Cements Containing Silica-Based Microspheres, Dylan Albers
LSU Master's Theses
Drilling through low pressure formations, either offshore or through depleted formations, requires the use of low density fluids to prevent lost circulation ensuring proper placement of cement for proper zonal isolation and structural integrity. Achieving these densities in cements can be done through foaming the cement, increasing water content, or using silica-based microspheres. Water extended cements are useful at densities down to 13 ppg below which only foaming and silica-based microspheres can be used. Each of these methods coming with individual limitations, with foamed cements being sensitive to high pressures and silica-based microspheres having chemical instability in the high alkalinity …