Engineering Commons^™

Advanced Ceramics And Composites Based On Rice Hulls, Peigen Zhang

LSU Doctoral Dissertations

As a by-product of the agricultural industry, rice hulls are available at large volume across the world. The disposal of the rice hulls itself is a big problem for the rice millers where the rice paddies are peeled off and rice hulls are produced. There have been many disposal methods developed, but the true value of the rice hulls would be more appreciated when they are employed to produce high value-added advanced ceramics. In this dissertation, advanced ceramics, such as AlN nanowires, SiC whiskers, mullite and SiC/Al2O3 nano-sized composites, were developed and studied based on the rice hulls. The SiC …

Synthesis, Characterization, And Testing Of Atomically-Precise Au Clusters Supported On Tio₂ For Co Oxidation, Sarthak Gaur

LSU Doctoral Dissertations

Supported Au catalysts have been studied extensively for CO oxidation. These catalysts are known to catalyze this reaction even at sub-ambient temperatures. While recent literature demonstrates catalytic activity of gold nanoparticles <2 nm, the next stage in fine tuning this catalysis process is to develop gold clusters prepared with atomic precision. Such atomically precise gold catalysts supported on TiO2 hitherto have not been investigated for CO oxidation. The main objective of this work is to synthesize atomically-precise Au38 clusters in a flask-based method using principles of wet chemistry, to characterize these clusters using various advanced spectroscopic techniques, and to test these clusters as potential catalytic materials for CO oxidation. Furthermore, we have tested TiO2-supported Au38 clusters and a commercially purchased Au/TiO2 catalyst for CO oxidation at 30 °C and 60 °C, and used DRIFTS as a probe spectroscopic technique to correlate kinetics with the mechanism occurring on the surface of both catalysts in order to device the mechanistic pathways for CO oxidation. The work reported in this dissertation is the first spectroscopic observation of the phenomena where sulfur may have beneficial effect on the catalytic activity of Au/TiO2 catalysts. Such an interesting observation where sulfur has beneficial effect on catalytic activity of Au/TiO2 catalysts has never been observed in the past. We have also synthesized and tested Fe3O4@Au core-shell nanoparticles supported on TiO2 for CO oxidation. We show for the first time that, core-shell type nanogold catalysts are better suited compared to pure gold nanoparticles for heterogeneous gas phase catalysis of CO oxidation. By conducting comprehensive experiments towards understanding CO oxidation catalysis using X-ray photoelectron spectroscopy, infrared spectroscopy, and temperature programmed reduction, we show that the enhanced catalytic activity is due to a combination of factors ranging from synergistic interaction between Au and Fe, complete removal of organic capping ligands and the presence of metallic gold (Au0) in the active catalyst.

Novel Surface Modifications And New Nanostructured Titania Synthesis For High-Performance Lithium-Ion Batteries And Solar Cells, Dongsheng Guan

LSU Doctoral Dissertations

With the rapid development of electronic devices, electrical vehicles and space aerocrafts, rechargeable lithium-ion batteries (LIBs) have attract numerous interests due to high energy and power density, long lifespan and low self discharge. Spinel LiMn2O4 is a promising cathode material for novel LIBs thanks to high working potential, easy synthesis and low cost, but its severe capacity drop mostly due to inevitable reactions with electrolytes is a drawback. In the dissertation, ultrathin and highly-conformal Al2O3 coatings are grown on the surface of micro-sized and nanosized LiMn2O4 with atomic layer deposition. Thickness of Al2O3 ALD coatings can be precisely controlled by …

Structural And Dynamical Properties Of Liquid And Solid Phases Of Ionic Liquids Confined Inside Nanoporous Materials, Ramesh Singh

LSU Doctoral Dissertations

The purpose of this research is to investigate the physical properties of ionic liquids (ILs) confined inside nanopores of different materials and morphologies. We are interested to study the effect of pore material, morphology and addition of organic solvents on the properties of confined ILs. Understanding the behavior of ILs inside nanopores is relevant to potential applications of these systems in electrochemical double layer capacitors (EDLCs) and dye sensitized solar cells (DSSCs). Such a fundamental understanding is also crucial to optimize the synthesis of hard-templated 1D nanostructures (nanorods, nanotubes, nanowires) based on organic salts, which may be imparted properties (e.g., …

Development Of Cost-Effective And Benign Lipid Extraction System For Microalgae, Javed Iqbal

LSU Doctoral Dissertations

A laboratory-made continuous flow lipid extraction system (CFLES) was devised to extract lipids from microalgae Nannochloropsis sp., a potential feedstock for biodiesel fuel, with a focus to assess the workable temperatures and pressures for possible scale-up applications. Using conventional solvents, the CFLES recovered 100% of the lipids recovered with conventional Soxhlet extraction (USEPA method 3540) at moderate 50 psi pressure and 100°C temperature; conditions significantly lower than those normally used in pressurized liquid extractions requiring specialized equipment. Approximately 87% of the extracted oil was successfully transesterified into biodiesel fuel. For exploring the solvent potential of biodiesel, CFLES was also tested …

A Safety Elements Model For The Building Construction Industry, Cliff Dunlap Dunlap

LSU Doctoral Dissertations

The Abstract was sent to Ms. McKenzie as an attachment to an e-mail

Efficacy Of Multifunctionalized Saccharide Constructs For The Attenuation Of Amyloid-Beta Toxicity, Dhruva Dilip Dhavale

LSU Doctoral Dissertations

There is evidence that amyloid-beta (Aβ) toxicity is mediated through interactions and binding with neuronal surface sialic acids in Alzheimer’s disease (AD). The binding affinity is higher if the sialic acids are clustered and toxicity of Aβ was attenuated by removal of neuronal sialic acids. Thus, interfering with cell membrane-Aβ binding using biomimetics that could reproduce the clustered sialic acid structure could present us with a potential target for therapeutic intervention in AD. Based on this hypothesis, we developed several multifunctionalized sialic acid labeled chitosan compounds of different valency, or number of sialic acid per chitosan molecule, to attenuate Aβ …

Controller Reduction For Linear Systems, Lili Kong

LSU Doctoral Dissertations

This dissertation proposes some H-infinity and H2 performance preserving controller reduction methods for linear systems. The proposed methods can guarantee robust stability and performance for the closed-loop system with the reduced order controllers. Several H-infinity stability and performance preserving controller reduction methods are proposed in this dissertation. It is shown that the weighting functions used in the proposed controller reduction methods can be directly obtained from the parametrization of the H-infinity controllers. Hence, comparing with the most existing controller reduction approaches, the proposed controller reduction methods require less computation and are easy to apply. At the same time, several algorithms …

A New Hybrid Approach For Forecasting Interest Rates, David Enke, Nijat Mehdiyev

Engineering Management and Systems Engineering Faculty Research & Creative Works

The dynamic, non-linear, volatile and complex nature of interest rates makes it hard to predict their future movements. in order to deal with these complexities, the authors propose a two-stage neuro-hybrid forecasting model. in the initial data preprocessing stage, multiple regression analysis is implemented to determine the variables that have the strongest prediction ability. the selected variables are then provided as inputs to a Fuzzy Inference Neural Network to forecast future interest rate values. the proposed hybrid model is implemented using data from the U.S. interest rate market. © 2012 Published by Elsevier B.V.

A Distributed Model Predictive Control For Multi-Agent Multi-Rate Systems, Samira Roshany-Yamchi

Theses

In this thesis, a new method is proposed to control multi-agent multi-rate systems with linear dynamics that are coupled via inputs and states. These systems are multi-rate in the sense that either output measurements or input updates are not available at certain sampling. Such systems can arise when the number of sensors is less than the number of variables to be controlled or when measurements of outputs cannot be completed simultaneously because of applicational limitations. The multi-rate nature gives rise to lack of information which will cause uncertainty in the system's performance.

The proposal is to control such systems with …

Development And Deployment Of A Bioreactor For The Removal Of Sulfate And Manganese From Circumneutral Coal Mine Drainage, C. B. Mastin, J. D. Edwards, Christopher D. Barton, Anastasios D. Karathanasis, Carmen T. Agouridis, Richard C. Warner

Forestry and Natural Resources Faculty Publications

Surface mining, in the form of contour mining and mountain-top removal, is a common means for retrieving coal in the Appalachian Coal Belt region of Kentucky. Overburden or excess spoil generated by these two methods is placed in valley fills. Traditionally Constructed fills have been shown to adversely impact headwater ecosystems via stream burial and through alterations to the hydrology, sediment supply, water quality and biological composition of downstream reaches. Mine drainages emanating from the toe of valley fills often contain elevated levels of total dissolved solids and heavy metals. Drainage chemistry from Guy Cove, a valley fill located in …

Geohazard Potential Of Rainfall Induced Slope Failure On Expansive Clay, Jubair Hossain

Civil Engineering Dissertations - Archive

Each year, rain induced slope failures cause significant damages in highway infrastructures and environments, as well as tragic losses of human lives around the world. Rainfall-induced slope failure is a common problem in areas with slope constructed on high plasticity clays. These post failure costs can be significantly reduced if precautions are taken ahead of time. Development of an early hazard warning system based on weather forecast data can help identify potential slopes susceptible to failure due to rainfall. But development of such system will require a better understanding of the in situ behavior of soil due to rainwater infiltration …

An Evaluation Of Large Diameter Steel Water Pipelines, Tushar Joshi

Civil Engineering Theses - Archive

Steel water pipelines, as a part of America's underground infrastructure, play a key role in maintaining the quality of life and well-being of communities. Thousands of miles of steel water pipelines make up a huge and complex water transmission system. This complexity generates the necessity for research on underground infrastructure in general and steel pipelines in particular. The objective of this research is to evaluate performance of large diameter (24 in. and larger) steel water pipelines. This research objective was achieved by use of a survey of various North American water utilities to provide details about their inventory. This data …

Degradation Of Triclosan By Sulfate Radicals Generated By Metal-Mediated Activation Of Oxidants, Prince Albert Nfodzo

Civil Engineering Dissertations - Archive

The presence of persistent and toxic compounds, especially pharmaceuticals and personal care products (PPCPs) in water resources has generated considerable scientific, regulatory, and public interests, requiring the development of cost-effective technologies for the management of PPCPs-contaminated water resources. In particular, triclosan (TCS, 5-chloro-2-(2,4-dichlorophenoxy)phenol), an important antimicrobial agent widely used in many PPCPs, has attracted significant attention due to its potential endocrine disrupting capabilities. In order to address these concerns, advanced oxidation processes (AOPs), resulting in the generation of stronger oxidizing species, typically hydroxyl radicals (HRs) and sulfate radicals (SRs), have been studied and proposed to be effective to degrade a …

An Improved Model For Predicting Methane Emissions From Landfills Based On Rainfall, Ambient Temperature And Waste Composition, Richa Vijay Karanjekar

Civil Engineering Dissertations - Archive

Accurately estimating the emissions of methane (CH4) and carbon dioxide (CO2) in a landfill is important for quantifying its greenhouse gas (GHG) emissions and power generation potential. Previous studies have shown that variation in waste composition, rainfall and ambient temperature of a landfill significantly influences its methane generation potential. Current methane generation models, namely U.S. Environmental Protection Agency's (EPA) Landfill Gas Generation Model (LandGEM) and Intergovernmental Panel on Climate Change's (IPCC) methane generation model, are overly simplified and do not account for the variations in waste composition, rainfall and ambient temperature. The goal of this research was to improve our …

Development Of A New Device To Evaluate Stabilization Durability Of Expansive Soils By Addressing Wetting/Drying And Leachate Issues, Priya Pravin Lad

Civil Engineering Theses - Archive

Expansive soils have been known to cause deterioration among all aspects of civil infrastructure for many years primarily due to the presence of clay minerals like Montmorillonite. Replacing these problematic soils is not a viable solution in that it is costly and time consuming.Although many stabilization techniques are available, chemical stabilization has proven to be an important tool in arresting the swell/shrink behavior of expansive soil, which is a major source of distress problems for most infrastructures built on this type of soils. Of the chemical stabilizers available in the market, lime and cement stabilizers are the two most widely …

Evaluation Of Algae Concentration In Manure Based Media, Maira Freire Pecegueiro Do Amaral

Theses and Dissertations--Biosystems and Agricultural Engineering

Algae can be used to treat wastewater and manure while producing a feedstock for renewable energy. Algae require nutrients to achieve their maximum growth and manure could provide those nutrients, thereby reducing the cost of algae production and the impact of manure treatment. Algae concentration during cultivation is a critical variable that is difficult to measure due to the high concentration of suspended solids present in manure. This dissertation addresses methods to measure algae concentration in the presence of manure solids.

Quantifying the algae concentration gravimetrically or by optical density was unreliable due to manure solids interfering with the measurement. …

Effect Of Additive Morphology & Chemistry On Wear & Friction Of Greases Under Spectrum Loading, Sujay Dilip Bagi

Material Science and Engineering Theses - Archive

The primary focus of grease development is to minimize friction and improve on wear and load bearing capacity. Traditional method to evaluate wear behavior of grease is based on ASTM D2266 which evaluates the performance of grease at 75°C, 40Kg and 1200 rpm for 1 hour. However, actual applications may require bearings to be subjected to spectrum loading conditions where-in rotations per minute (rpm), load and duration of test are variables. A series of six tests were conducted for all the grease blends; load was treated as the variable in four of the tests while maintaining the frequency constant and …

Design And Production Aspects Of An Electroluminescent Segment Display, Veronica Kopp, Chris Nixon

Graphic Communication

The purpose of this study was to get a better understanding of the different ways printed circuits could be constructed and then implemented into creative, visual designs for printed electroluminescent displays. A variety of circuit design variables, such as area and length, were tested that will help create solutions for printed electronics.

This study tested different variables of circuit design, such as length of silver traces and the size of the image area, to help optimize ways to build a printed circuit. Then, findings were implemented into a segmented graphic display in order to analyze innovative ways to utilize multiple …

Privacy Preserving Distributed Data Mining, Zhenmin Lin

Theses and Dissertations--Computer Science

Privacy preserving distributed data mining aims to design secure protocols which allow multiple parties to conduct collaborative data mining while protecting the data privacy. My research focuses on the design and implementation of privacy preserving two-party protocols based on homomorphic encryption. I present new results in this area, including new secure protocols for basic operations and two fundamental privacy preserving data mining protocols.

I propose a number of secure protocols for basic operations in the additive secret-sharing scheme based on homomorphic encryption. I derive a basic relationship between a secret number and its shares, with which we develop efficient secure …

Measuring Effectiveness Of Address Schemes For As-Level Graphs, Yinfang Zhuang

Theses and Dissertations--Computer Science

This dissertation presents measures of efficiency and locality for Internet addressing schemes.

Historically speaking, many issues, faced by the Internet, have been solved just in time, to make the Internet just work~\cite{justWork}. Consensus, however, has been reached that today's Internet routing and addressing system is facing serious scaling problems: multi-homing which causes finer granularity of routing policies and finer control to realize various traffic engineering requirements, an increased demand for provider-independent prefix allocations which injects unaggregatable prefixes into the Default Free Zone (DFZ) routing table, and ever-increasing Internet user population and mobile edge devices. As a result, the DFZ routing …

Development Of A Bi-Directional Electronics Platform For Advanced Neural Applications, Luca Abbati

USF Tampa Graduate Theses and Dissertations

This work presents a high-voltage, high-precision bi-directional multi-channel system capable of stimulating neural activity through bi-phasic pulses of amplitude up to ∓50 V while recording very low-voltage responses as low as tens of microvolts. Most of the systems reported from the scientific community possess at least one of the following common limitations: low stimulation voltages, low gain capabilities, or insufficient bandwidth to acquire a wide range of different neural activities.

While systems can be found that present remarkable capabilities in one or more specific areas, a versatile system that performs over all these aspects is missing. Moreover, as many novel …

Improving The Throughput And Reliability Of Wireless Sensor Networks With Application To Wireless Body Area Networks, Gabriel Arrobo

USF Tampa Graduate Theses and Dissertations

This dissertation will present several novel techniques that use cooperation and diversity to improve the performance of multihop Wireless Sensor Networks, as measured by throughput, delay, and reliability, beyond what is achievable with conventional error control technology.

We will investigate the applicability of these new technologies to Wireless Body Area Networks (WBANs) an important emerging class of wireless sensor networks. WBANs, which promise significant improvement in the reliability of monitoring and treating people's health, comprise a number of sensors and actuators that may either be implanted in vivo or mounted on the surface of the human body, and which are …

A Radar-Enabled Collaborative Sensor Networking Integrating Cots Technology For Surveillance And Tracking, Robert Kozma, Lan Wang, Khan Iftekharuddin, Ernest Mccracken, Muhammad Khan, Khandakar Islam, Sushil R. Bhurtel, R. Murat Demirer

Electrical & Computer Engineering Faculty Publications

The feasibility of using Commercial Off-The-Shelf (COTS) sensor nodes is studied in a distributed network, aiming at dynamic surveillance and tracking of ground targets. Data acquisition by low-cost (<$50 US) miniature low-power radar through a wireless mote is described. We demonstrate the detection, ranging and velocity estimation, classification and tracking capabilities of the mini-radar, and compare results to simulations and manual measurements. Furthermore, we supplement the radar output with other sensor modalities, such as acoustic and vibration sensors. This method provides innovative solutions for detecting, identifying, and tracking vehicles and dismounts over a wide area in noisy conditions. This study presents a step towards distributed intelligent decision support and demonstrates effectiveness of small cheap sensors, which can complement advanced technologies in certain real-life scenarios.

Basal Graph Structures For Geometry Based Organization Of Wide-Baseline Image Collections, Aveek Shankar Brahmachari

USF Tampa Graduate Theses and Dissertations

We propose algorithms for organization of images in wide-area sparse-view datasets. In such datasets, if the images overlap in scene content, they are related by wide-baseline geometric transformations. The challenge is to identify these relations even if the images sparingly overlap in their content. The images in a dataset are then grouped into sets of related images with the relations captured in each set as a basal (minimal and foundational) graph structures. Images form the vertices in the graph structure and the edges define the geometric relations between the images. We use these basal graphs for geometric walkthroughs and detection …

Quantification Of Nox Reduction Via Nitrate Accumulation On A Tio2 Photocatalytic Concrete Pavement, David James Osborn

LSU Master's Theses

Field trials of photocatalytic pavements were recently initiated and are presently being considered by many states (e.g., Virginia, Texas, New York, and Missouri). Results from this study originate from the country’s first air-purifying asphalt and concrete photocatalytic pavements, constructed on Dec. 20, 2010. The test area is a pavement site located on the LSU campus. The objective of the study is to validate field photocatalytic degradation of NOx in a field environment by measuring the day to day accumulation of the oxidized byproduct; nitrate salts. The mass of nitrates, produced by the real life photocatalytic pavement, were measured. The measurement …

The Use Of A Mixed Chlorella Cyanobacteria Culture As A Protein Source For Aquaculture, Marjan Sadat Mohtashamian

LSU Master's Theses

The increase in the global demand for fish feed in the last decades has resulted in the over exploitation of natural resources to produce more fishmeal supplies for aquaculture industry. The supply issues and high prices of fishmeal products have raised the incentives to seek for suitable alternatives to replace fishmeal protein. As a by-product of biofuel production process, residual microalgal biomass may be a low cost feed ingredient to the aquaculture diet. The potential of the use of a post lipid extraction Chlorella vulgaris/Leptolyngbya sp. Co-Culture (Louisiana co-culture) as a protein source in aquaculture feeds could help offset fishmeal. …

Stabilization Of Very Weak Subgrade Soil With Cementitious Stabilizers, Sanjay Kumar Dhakal

LSU Master's Theses

To evaluate the effect of high moisture content on the performance of weak subgrade soil and improve the engineering properties of weak subgrade soil through using cementitious materials, five different soils that represent range of subgrade soil in Louisiana (based on plasticity indices) were collected and considered in this research study. All tests on raw soils and treated/stabilized soils were performed on the soil laboratory at the Louisiana Transportation Research Center (LTRC). Ordinary Portland cement and hydrated lime were selected in this study to treat/stabilize the subgrade soils depending upon the soil type and plasticity index. The repeated load triaxial …

Microencapsulation Of Self-Healing Concrete Properties, James Gilford Iii

LSU Master's Theses

ABSTRACT Recent studies in the literature have demonstrated the ability of self-healing processes to be effective in enhancing the overall life of concrete. The main goal of this project is to evaluate and to control specific parameters for the production of an effective self-healing matrix that can be utilized within the application of self-healing concrete. Therefore, the project objective is to synthesize microcapsules using dicyclopentadine and sodium silicate and to evaluate the effects of pH, temperature, and agitation rate on microcapsule morphology. The microcapsule diameter, yield analysis, and shell thickness were characterized using scanning electron microscopy. During the experimental analysis, …

Experimental And Numerical Investigation Of Pilot Scale Microwave Assisted Transesterification Process For Biodiesel Production, Pranjali D. Muley

LSU Master's Theses

The goal of this study was to design and test a pilot scale process for biodiesel production using advanced microwave technology and develop a numerical model for investigating various parameters affecting this process. Dielectric properties of materials play a major role in microwave design of a process. The dielectric properties (dielectric constant ε’ and dielectric loss ε”) of biodiesel precursors: soybean oil, alcohols and catalyst and their different mixtures were measured at four different temperatures (30°C, 45°C, 60°C and 75°C) and in the frequency range of 154 MHz to 4.5 GHz. Results indicate that the microwave dielectric properties of almost …