Engineering Commons^™

Growth Of Silver Nanoparticles On Transparent Substrates From Liquid Precursors: Improvements And Applications, Carlos Andrés Jarro Sanabria

Theses and Dissertations--Electrical and Computer Engineering

Interest in controlling the synthesis of silver nanoparticles in colloidal solutions has increased during the last two decades. There is also growing interest in forming layers of silver nanoparticles on substrates, particularly for surface-enhanced Raman spectroscopy applications. However, methods to grow silver nanoparticles directly on substrates have not been studied extensively, and there are few techniques for controlling the size, shape, density, and location of the particles. This work presents a simple and reliable method to photodeposit silver nanoparticles onto transparent substrates. The size, shape and deposition density of the nanoparticles are influenced by the precursor solution, light intensity, and …

Characterization And Uncertainty Analysis Of Siliciclastic Aquifer-Fault System, Ahmed Saad Elshall

LSU Doctoral Dissertations

The complex siliciclastic aquifer system underneath the Baton Rouge area, Louisiana, USA, is fluvial in origin. The east-west trending Baton Rouge fault and Denham Springs-Scotlandville fault cut across East Baton Rouge Parish and play an important role in groundwater flow and aquifer salinization. To better understand the salinization underneath Baton Rouge, it is imperative to study the hydrofacies architecture and the groundwater flow field of the Baton Rogue aquifer-fault system. This is done through developing multiple detailed hydrofacies architecture models and multiple groundwater flow models of the aquifer-fault system, representing various uncertain model propositions. The hydrofacies architecture models focus on …

Characterization And Verification Of A Closed Loop Wind Tunnel With A Linear Cascade And Upstream Wake Generator, Christopher Foreman

LSU Master's Theses

A closed loop wind tunnel designed to study film cooling was completed in May 2011 along with a removable wake generating device. The test section featured a three blade, four passage linear cascade utilizing the Air Force Office of Scientific Research L1A low pressure turbine blade. The wake generator is unique because its blades are flat plates with round leading and trailing edges instead of circular rods. In this report, the test section of the wind tunnel is characterized and validated through velocity and pressure measurements in the test section. Hot-wire surveys were used to characterize the velocity and turbulence …

High Capacity Digital Beam Steering Technology, Daniel James Hebert

LSU Doctoral Dissertations

A novel method is described in detail for steering light in many directions without moving mechanical parts. The method involves a combination of liquid crystal cells and polarizing beam splitters. The polarization at each beam splitter is controlled by applying a signal to its corresponding liquid crystal cell. A study of light steering techniques is described for efficient beam placement, in a line and plane. These techniques permit accurate, non-mechanical, beam steering limited by the response time of the liquid crystal cells. A theoretical limit to the number of discrete directions is described and closely approached for a one dimensional …

Heterogeneous Volumetric Data Mapping And Its Medical Applications, Huanhuan Xu

LSU Doctoral Dissertations

With the advance of data acquisition techniques, massive solid geometries are being collected routinely in scientific tasks, these complex and unstructured data need to be effectively correlated for various processing and analysis. Volumetric mapping solves bijective low-distortion correspondence between/among 3D geometric data, and can serve as an important preprocessing step in many tasks in compute-aided design and analysis, industrial manufacturing, medical image analysis, to name a few. This dissertation studied two important volumetric mapping problems: the mapping of heterogeneous volumes (with nonuniform inner structures/layers) and the mapping of sequential dynamic volumes. To effectively handle heterogeneous volumes, first, we studied the …

Influence Of Flue Gas Components On The Growth Rate Of Chlorella Vulgaris And Scenedesmus Acutus, Czarena Crofcheck, Aubrey Shea, Michael D. Montross, Mark Crocker, Rodney Andrews

Biosystems and Agricultural Engineering Faculty Publications

Atmospheric carbon dioxide levels have increased since the industrial revolution due to the increase in combustion of fossil fuels. One possible alternative strategy is the use of microalgae for CO₂ capture and recycling. Major components in coal-derived flue gas that may accumulate and effect algae growth include both sulfur oxides and fly ash. However, in practical application, sulfur oxides will be converted quickly to the acid product (H₂SO₄) in the aerobic aqueous conditions of algae cultivation. In this article, the influence of elevated H₂SO₄ levels and the presence of coal-derived fly ash …

Analysis And Optimization Of Film Cooling Effectiveness, Hessam Babaee

LSU Doctoral Dissertations

In the first part, an optimization strategy is described that combines high-fidelity simu- lations with response surface construction, and is applied to pulsed film cooling for turbine blades. The response surface is constructed for the film cooling effectiveness as a function of duty cycle, in the range of DC between 0.05 and 1, and pulsation frequency St in the range of 0.2-2, using a pseudo-spectral projection method. The jet is fully modulated and the blowing ratio, when the jet is on, is 1.5 in all cases. Overall 73 direct numerical sim- ulations (DNS) using spectral element method were performed to …

Fe(Iii)2o3 Nanoparticle Mediated Molecular Growth And Soot Particle Inception From The Oxidative Pyrolysis Of 1-Methylnaphthalene, Michael Paul Herring

LSU Doctoral Dissertations

The potential for Fe(III)2O3 nanoparticles to participate in the molecular growth and particle inception of soot from 1-methylnapthalene (1-MN) was studied in a dual-zone, high-temperature flow reactor. An iron substituted, dendrimer template was oxidized in the Zone 1 reactor to generate ~5nm Fe(III)2O3 nanoparticles, that were continually seeded to a high sooting 1-MN fuel under oxidative pyrolysis conditions. The Fe(III)2O3 nanoparticles could then influence the otherwise gas-phase reactions of 1-MN. Increased PAH formation, soot number density, soot mass yield, and soot radical intensity were observed as a result of Fe(III)2O3 nanoparticle introduction prior to soot inception. Low Temperature Matrix Isolation-Electron …

A Dynamic Feedback-Control Toll Pricing Methodology : A Case Study On Interstate 95 Manged Lanes, Danhong Cheng

LSU Master's Theses

Recently, congestion pricing emerged as a cost-effective and efficient strategy to mitigate the congestion problem on freeways. This study develops a feedback-control based dynamic toll approach to formulate and solve for optimal tolls. The study compares the performance of the proposed methodology to that of the current strategy deployed on Interstate 95 express lanes. Two objectives are studied: one is to maximize the toll revenue while maintaining a minimum level of service on the managed lanes and the other is to maximize both revenue and throughput on the managed lanes while keeping a minimum level of service. The impact of …

Camber Control In Simply Supported Prestressed Concrete Bridge Girders, Osamah Ibrahim Mahmood

Theses and Dissertations--Civil Engineering

When designing a bridge, serviceability usually controls and is a more important factor than the ultimate capacity of the bridge or the allowable stresses. Therefore, the behavior of the bridge girder deflection and camber must be predicted as accurately as possible. Therefore, excessive camber has become one of the most common problems when constructing concrete bridges. Different methods have been developed to overcome this problem. The most common and widely used is using haunch with adjustable pedestals to overcome the excessive camber. However, this method has limitations that must be considered. Therefore, this study is evaluating the effectiveness of using …

Predicting The Dynamic Behavior Of Coal Mine Tailings Using State-Of-Practice Geotechnical Field Methods, Ali Salehian

Theses and Dissertations--Civil Engineering

This study is focused on developing a method to predict the dynamic behavior of mine tailings dams under earthquake loading. Tailings dams are a by-product of coal mining and processing activities. Mine tailings impoundments are prone to instability and failure under seismic loading as a result of the mechanical behavior of the tailings. Due to the existence of potential seismic sources in close proximity to the coal mining regions in the United States, it is necessary to assess the post-earthquake stability of these tailings dams.

To develop the aforementioned methodology, 34 cyclic triaxial tests along with vane shear tests were …

Applying Cognitive Principles To The Delivery Of Engineering Information By Different Mediums, Gabriel B. Dadi

Theses and Dissertations--Civil Engineering

Construction project performance and worker productivity are often tied to the availability and effective presentation of information, tools, materials, and equipment. While advancements in technology have improved much of the processes on a construction project, the medium of information dissemination at the construction work face has consistently relied on the use of two dimensional drawings and specifications.

Industry initiatives are driving increased collaboration through three dimensional BIM (Building Information Modeling) models. However, the added dimension partially loses its effect when presented on a two dimensional computer monitor. Other computer forms of presentation intended for mobility (PDAs, laptops, and tablets) can …

Water Quality Sensor Placement Guidance For Small Water Distribution Systems, Stacey L. Schal

Theses and Dissertations--Civil Engineering

Water distribution systems are vulnerable to intentional, along with accidental, contamination of the water supply. Contamination warning systems (CWS) are strategies to lessen the effects of contamination by delivering early indication of an event. Online quality monitoring, a network of sensors that can assess water quality and alert an operator of contamination, is a critical component of CWS, but utilities are faced with the decision of what locations are optimal for deployment of sensors. A sensor placement algorithm was developed and implemented in a commercial network distribution model (i.e. KYPIPE) to aid small utilities in sensor placement. The developed sensor …

Development Of A Constitutive Model Of Compacted Shales And Determination Of The Effect Of Weathering On Its Parameters, Isabel Cristina Gomez-Gutierrez

Theses and Dissertations--Civil Engineering

Compacted shales cause problems because they tend to degrade with time due to weathering. Degradation results in the shale deteriorating from a hard rock-like material to a soft fine-grained soil mass with lower shear strength and high deformability. Consequently, common problems that occur in embankments constructed with compacted shales include settlement and instabilities. Therefore, accelerating weathering prior to compaction by wetting and breaking down the shales before placement can reduce the deterioration during the service life of the construction. Extensive laboratory testing was performed in order to characterize the mechanical behavior of compacted shales.

Critical State theory is a clever …

Pressure Measurement At The Ballast-Tie Interface Of Railroad Track Using Matrix Based Tactile Surface Sensors, Michael T. Mchenry

Theses and Dissertations--Civil Engineering

The pressure distribution at the ballast-tie interface of railroad track plays a key role in overall track support. Failure of the ballast or tie can result from excessive loads that were not designed for, requiring increased maintenance and reducing railroad operating efficiency. Understanding the forces acting on the ballast and tie are required to design higher performance and longer lasting track. To further this understanding, the use of Matrix Based Tactile Surface Sensors (MBTSS) is employed to measure the actual pressure distribution at the ballast-tie interface, characterized by individual ballast particle contact points and non-uniform pressures. The research explores this …

Optimal Consignment Stocking Policies For A Supply Chain Under Different System Constraints, Hui Zhi Yi

LSU Doctoral Dissertations

The research aims are to enable the decision maker of an integrated vendor-buyer system under Consignment Stock (CS) policy to make the optimal/sub-optimal production/replenishment decisions when some general and realistic critical factors are considered. In the system, the vendor produces one product at a finite rate and ships the outputs by a number of equal-sized lots within a production cycle. Under a long-term CS agreement, the vendor maintains a certain inventory level at the buyer’s warehouse, and the buyer compensates the vendor only for the consumed products. The holding cost consists of a storage component and a financial component. Moreover, …

The Uplift Resistance Of Spartina Alterniflora In A Louisiana Salt Marsh, James Madison Bouanchaud Iii

LSU Master's Theses

The uprooting resistance of Spartina Alterniflora was measured in Terrebonne Bay and Bay Jimmy, both of which are located in Louisiana. The parameters collected included plant uprooting resistance, stem diameter, and stem height. Seasonal variations and site specific properties were considered. A device was designed and constructed that was able to perform the specific testing under the constraints of the field site. The device consisted of a winch mounted to a tripod and connected to an inline load cell to measure the uprooting resistance. The data sets were analyzed to determine the relationship between the uprooting resistance and the physical …

Coastal Plants For Biofuel Production And Coastal Preservation, Chester Charles Malveaux

LSU Master's Theses

ABSTRACT Sustainable and renewable biofuels as well as coastal preservation are important to the State of Louisiana which is losing its coastline at the rate of up to 100 square kilometers per year. This has important implications for other coastal areas worldwide. By managing water hyacinth in canals and lakes in coastal Louisiana the biomass of this fast growing aquatic plant can reduce coastal erosion by absorbing wave energy, and remediate waste water through bioabsorption of contaminants, while also providing a source of biofuel. This research has shown that coastal vegetation can play a part in lessening the impact of …

Induction Motors With Rotor Helical Motion, Ebrahim Amiri

LSU Doctoral Dissertations

Performance analysis of the twin-armature rotary-linear induction motor, a type of motor with two degrees of mechanical freedom, is the subject of this dissertation. The stator consists of a rotary armature and linear armature placed aside one another. Both armatures have a common rotor which can be either solid or cage rotor. The rotor can move rotary, linearly or with helical motion. The linear motion generates dynamic end effect on both linear and rotary armature. Modeling such an effect in rotary armature is a significant challenge as it requires a solution considering motion with two degrees of mechanical freedom. In …

Modeling Temporal And Spatial Variations In Dissolved Oxygen In Amite River, Vahid Zahraeifard

LSU Doctoral Dissertations

A watershed-based modeling framework is developed in this dissertation for simulating temporal and spatial variations in DO in lowland rivers with organic-rich fine-grained sediment. The modeling framework is based on three major contributions/new models, including (1)VART-DO model for improved estimation of reaeration coefficient (K2) in natural streams, (2)VART-DOS model for simulation of temporal variations in DO in response to sediment resuspension, and (3)VART DO-3L model for simulation of spatial variations in DO. A major advantage of VART-DO model is the capability of simulating DO exchange across the water-sediment interface through the hyporheic exchange mechanism in addition to the air-water exchange. …

The Investigation Of Valve Operators' Torque Production Capabilities And Optimal Handwheel Height, Angle, And Opening Technique, Saif K. Al-Qaisi

LSU Doctoral Dissertations

This research consists of two projects concerned with handwheel-valve operations. The objectives of poject-1 were to: (1) introduce an ergonomically-modified valve-wrench and compare it to conventional valve-opening methods, in terms of efficiency (time to open valve), perceived physical exertion (Borg-scale), and muscle loading of shoulder and trunk muscles; and (2) determine whether the torque setting (15 Nm and 30 Nm) of the valve affects the preferred valve-opening method. Four methods were evaluated, including using bare hands (BH), conventional wrench-restricted (CW-R, assumes presence of obstructions), conventional wrench-unrestricted (CW-U, assumes no obstructions), and modified wrench (MW). Electromyography (EMG) activities were measured from …

Electric Field Influence On The Combustion Of Fuel Droplets, Solomon Benghan

LSU Master's Theses

Improving the combustion efficiency of fuels in combustion devices has become imperative in the face of the diminishing rate of the discovery of new energy sources and an ever increasing demand for energy. While there are other ways of improving combustion efficiency, this study investigated the effect of electric field on the combustion of fuel droplets. In order to model the physics of the problem, a mass transfer evaporation model, heat transfer evaporation model and a simple burning droplet model were considered and their result compared to existing result from literature. A burning rate constant of 1.380mm2/s, 14.910mm2/s and 0.612mm2/s …

Liposomal Uptake Of Silver And Gold Nanoparticles, Dipon Chanda

LSU Master's Theses

The main objective of this work is to study the liposomal uptake of silver and old nanoparticles. Liposomes were prepared in Heating Method. The phospholipids used to prepare liposomes are 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (16:0 PC); 1,2-dipalmitoyl-sn-glycero-3-phospho-(1'-rac-glycerol) (16:0 PG); 1,2-distearoyl-sn-glycero-3-phosphocholine (18:0 PC); 1,2-distearoyl-sn-glycero-3-phospho-(1'-rac-glycerol) (sodium salt) (18:0 PG).Four different combinations of phospholipids were used to prepare liposomes. In all four combinations two types of phospholipids were used. The liposomes were incubated for 30 minute, 1 hour, 2 hour and 4 hour with silver and gold nanoparticles in streptavidin coated glass slide. All four liposomal formulations had a biotinylated lipid (1-oleoyl-2-[12-biotinyl(aminododecanoyl)]-sn-glycero-3-phosphocholine) which has a string …

Automatic Performance Level Assessment In Minimally Invasive Surgery Using Coordinated Sensors And Composite Metrics, Sami Taha Abu Snaineh

Theses and Dissertations--Computer Science

Skills assessment in Minimally Invasive Surgery (MIS) has been a challenge for training centers for a long time. The emerging maturity of camera-based systems has the potential to transform problems into solutions in many different areas, including MIS. The current evaluation techniques for assessing the performance of surgeons and trainees are direct observation, global assessments, and checklists. These techniques are mostly subjective and can, therefore, involve a margin of bias.

The current automated approaches are all implemented using mechanical or electromagnetic sensors, which suffer limitations and influence the surgeon’s motion. Thus, evaluating the skills of the MIS surgeons and trainees …

Algorithms For Fault Tolerance In Distributed Systems And Routing In Ad Hoc Networks, Qiangfeng Jiang

Theses and Dissertations--Computer Science

Checkpointing and rollback recovery are well-known techniques for coping with failures in distributed systems. Future generation Supercomputers will be message passing distributed systems consisting of millions of processors. As the number of processors grow, failure rate also grows. Thus, designing efficient checkpointing and recovery algorithms for coping with failures in such large systems is important for these systems to be fully utilized. We presented a novel communication-induced checkpointing algorithm which helps in reducing contention for accessing stable storage to store checkpoints. Under our algorithm, a process involved in a distributed computation can independently initiate consistent global checkpointing by saving its …

Variability Of Extreme Precipitation In Coastal River Basins Of The Southern Mexican Pacific Region, Nancy Perez-Morga, Thomas Kretzschmar, Tereza Cavazos, Stephen V. Smith, Francisco Munoz-Arriola

Biological Systems Engineering: Papers and Publications

Extreme wet and dry years (± 1 standard deviation, respectively), as well as the top 95 percentile (P95) of daily precipitation events, derived from tropical cyclone (TC) and nontropical cyclone (NTC) rainfall, were analyzed in coastal river basins in Southern Oaxaca, Mexico (Río Verde, Río Tehuantepec, and the Southern Coast). The study is based on daily precipitation records from 47 quality-controlled stations for the 1961 to 1990 period and TC data for the Eastern Tropical Pacific (EPAC). The aim of this study was to evaluate extreme (dry and wet) trends in the annual contribution of daily P95 precipitation events and …

Impact Of Water And Nitrogen Management Strategies On Maize Yield And Water Productivity Indices Under Linear-Move Sprinkler Irrigation, Daran Rudnick, Suat Irmak

Biological Systems Engineering: Papers and Publications

With uncertainty in future irrigation water availability and regulations on nutrient application amounts, experimentally determined effects of “controllable” management strategies such as nitrogen (N), water, and their combination on crop water productivity (CWP, also known as crop water use efficiency) and actual evapotranspiration (ET_a) are essential. The effects of various N application rates (0, 84, 140, 196, and 252 kg ha^-1) under fully irrigated (FIT), limited irrigation (75% FIT), and rainfed conditions on maize (Zea mays L.) yield and various CWP indices were investigated in 2011 and 2012 growing seasons under linear-move sprinkler irrigation in south …

Evapotranspiration And Surface Energy Balance Of A Common Reed-Dominated Riparian System In The Platte River Basin, Central Nebraska, Isa Kabenge, Suat Irmak, John E. Gilley, George E. Meyer, Stevan Z. Knezevic, Timothy J. Arkebauer, Duane Woodward, Milton Moravek

Biological Systems Engineering: Papers and Publications

Quantifying actual evapotranspiration (ET_a) of riparian zones is important for more robust water balance analyses that will enable better planning, managing, and allocating of water resources as well as developing strategies to protect delicate riparian ecosystem functions. The ET_a, sensible heat flux (H), net radiation (R_n), soil heat flux (G), meteorological variables (air temperature, T_a; incoming shortwave radiation, R_s; wind speed, u₃; relative humidity, RH; vapor pressure deficit, VPD; precipitation, etc.), and albedo were measured on an hourly time step, and leaf area index (LAI) and plant height …

Acetyl-Coa Carboxylases Are Checkpoints In Adipocyte Differentiation, Elizabeth Lyn Cordonier, Daniel Camara Teixeira, Zhonghi Han, Angela K. Pannier, Janos Zempleni

Biological Systems Engineering: Papers and Publications

No abstract provided.

Avhrr-Ndvi-Based Crop Coefficients For Analyzing Long-Term Trends In Evapotranspiration In Relation To Changing Climate In The U.S. High Plains, Denis Mutiibwa, Suat Irmak

Biological Systems Engineering: Papers and Publications

Studies in regions of extensive irrigation practices have revealed a significant influence of evaporative cooling on regional temperatures as a result of surface energy redistribution during evaporation. In the U.S. High Plains, maximum temperatures during the last quarter of the 20th century have been decreasing. We investigated the trends in evapotranspiration (ET or latent heat) fluxes originating from increasing irrigation practices in the High Plains region from 1981 to 2008. We estimated actual ET (ETc) over the entire High Plains from the spatial crop coefficients (Kc) and spatial reference (potential) ET (ETref). We proposed …