Engineering Commons^™

Efficient Generalized Inverse For Solving Simultaneous Linear Equations, S. Kadiam Bose, D. T. Nguyen

Civil & Environmental Engineering Faculty Publications

Solving large scale system of Simultaneous Linear Equations (SLE) has been (and continue to be) a major challenging problem for many real-world engineering and science applications. Solving SLE with singular coefficient matrices arises from various engineering and sciences applications [1]-[6]. In this paper, efficient numerical procedures for finding the generalized (or pseudo) inverse of a general (square/rectangle, symmetrical/unsymmetrical, non-singular/singular) matrix and solving systems of Simultaneous Linear Equations (SLE) are formulated and explained. The developed procedures and its associated computer software (under MATLAB [7] computer environment) have been based on "special Cholesky factorization schemes" (for a singular matrix). Test matrices from …

Lateral-Torsional Buckling Of Frp I-Section Beams, Mojtaba B. Sirjani, Zia Razzaq

Civil & Environmental Engineering Faculty Publications

This paper presents the outcome of an experimental and theoretical investigation into the load-carrying capacity of Fiber Reinforced Polymer (FRP) I-section beams subjected to four-point loading. The overall lateral-torsional buckling, web and flange local buckling as well as material rupture load estimates are also made using the American Society of Civil Engineers Load and Resistance Factor Design (ASCE-LRFD) Pre-Standard for FRP Structures. Lateral-torsional buckling failure mode is found to govern for each of the beams studied. The study also revealed that the height of applied loads relative to the shear center has a very significant influence on lateral-torsional buckling load …

Elasto-Plastic Transient Dynamic Response Of Tubular Section Steel Cantilever Beam Under Impact Loading, Alial Aloosi, Zia Razzaq

Civil & Environmental Engineering Faculty Publications

This paper presents the outcome of an experimental and theoretical investigation into the loadcarrying capacity of Fiber Reinforced Polymer (FRP) I-section beams subjected to four-point loading. The overall lateral-torsional buckling, web and flange local buckling as well as material rupture load estimates are also made using the American Society of Civil Engineers#x2019; Load and Resistance Factor Design (ASCELRFD) Pre-Standard for FRP Structures. Lateral-torsional buckling failure mode is found to govern for each of the beams studied. The study also revealed that the height of applied loads relative to the shear center has a very significant influence on lateral-torsional buckling load …

Transformation Model With Constraints For High Accuracy Of 2d-3d Building Registration In Aerial Imagery, Guoqing Zhou, Qingli Luo, Wenhan Xie, Tao Yue, Jingjin Huang, Yuzhong Shen

Computational Modeling & Simulation Engineering Faculty Publications

This paper proposes a novel rigorous transformation model for 2D-3D registration to address the difficult problem of obtaining a sufficient number of well-distributed ground control points (GCPs) in urban areas with tall buildings. The proposed model applies two types of geometric constraints, co-planarity and perpendicularity, to the conventional photogrammetric collinearity model. Both types of geometric information are directly obtained from geometric building structures, with which the geometric constraints are automatically created and combined into the conventional transformation model. A test field located in downtown Denver, Colorado, is used to evaluate the accuracy and reliability of the proposed method. The comparison …

Relay Selection Strategies For Multi-Hop Cooperative Networks, Hui Sun

LSU Doctoral Dissertations

In this dissertation we consider several relay selection strategies for multi-hop cooperative networks. The relay selection strategies we propose do not require a central controller (CC). Instead, the relay selection is on a hop-by-hop basis. As such, these strategies can be implemented in a distributed manner. Therefore, increasing the number of hops in the network would not increase the complexity or time consumed for the relay selection procedure of each hop. We first investigate the performance of a hop-by-hop relay selection strategy for multi-hop decode-and-forward (DF) cooperative networks. In each relay cluster, relays that successfully receive and decode the message …

Application Of The Variational Fracture Model To Hydraulic Fracturing In Poroelastic Media, Chukwudi Chukwudozie

LSU Doctoral Dissertations

Hydraulic fracturing has persisted through the use of simple numerical models to describe fracture geometry and propagation. Field tests provide evidence of interaction and merging of multiple fractures, complex fracture geometry and propagation paths. These complicated behaviors suggest that the simple models are incapable of serving as predictive tools for treatment designs. In addition, other commonly used models are designed without considering poroelastic effects even though a propagating hydraulic fracture induces deformation of the surrounding porous media. A rigorous hydraulic fracturing model capable of reproducing realistic fracture behaviors should couple rock deformation, fracture propagation and fluid flow in the both …

Molecular Simulation Study Of Oil Hydrocarbons, Dispersants And Other Organics In Atmospheric Air/Water Interfaces, Zenghui Zhang

LSU Doctoral Dissertations

The main objective of this dissertation is to study the interfacial properties of organic contaminants, in particular green leaf volatiles (GLVs), oil hydrocarbons [mainly intermediate-volatile organic compounds (IVOCs) and semi-volatile organic compounds (SVOCs)], as well as surfactant species (i.e. DOSS and Span 80) from Corexit dispersants at atmospheric air/water and air/seawater interfaces. All these compounds can significantly contribute to the formation of secondary organic aerosols (SOAs). Furthermore, our simulation work on IVOCs, SVOCs and Corexit surfactants, combining with experiments from the Valsaraj group, suggests that these compounds can be adsorbed on the surface of seawater droplets and aerosolized into the …

Impacts Of Rock-Brine Interactions On Petrophysical Properties Of A Sandstone Reservoir, Utilizing Geochemical And Pore Network Modeling, Masoud Safari-Zanjani

LSU Doctoral Dissertations

Unfavorable consequences of geochemical reactions, such as calcite and silica scaling, in geothermal power plant surface facilities have been discussed in many recent studies. However, the impact of brine-rock interactions related to geothermal projects on reservoir properties has not been addressed fully. In this study, interactions between geothermal fluid and reservoir rocks in two fields located in Vermilion Parish, LA, and Chocolate Bayou, TX, are examined using geochemical modeling. The studied reservoir belongs to the Frio formation. In the geochemical models, the brine is cooled down to the estimated output temperature of a geothermal heat exchanger and re-equilibrated. Then, brine-rock …

Thermophysical And Thermochemical Property Measurement And Prediction Of Liquid Metal Titanium Alloys With Applications In Additive Manufacturing, Jonathan Richard Raush

LSU Doctoral Dissertations

Accurate high-temperature thermophysical property data for liquid metals and alloys are important for simulation of laser-based 3D printing processes. To understand and better control such additive manufacturing processes, knowledge of density, viscosity, and surface tension of liquid metals and alloys versus composition and temperature is needed. Likewise, thermochemical property data information regarding alloys, including chemical activities and free energies relative to composition and temperature, aid in the understanding and development of phase data important in the material design process. Vacuum electrostatic levitation (ESL) is an important technique through which both thermophysical and thermochemical property measurements can be accomplished without physical …

Application Of The Finite Element Method To Solve Coupled Multiphysics Problems For Subsurface Energy Extraction, Milad Ahmadi

LSU Doctoral Dissertations

Fractures are a source of extra compliance in the rock mass. Fracture compliance can estimate the fracture roughness and the type of fluid filling the fracture. The focus of this research study in chapter 2 is to illustrate how the compliance ratio of rough fractures can diverge from the compliance ratio of smooth fractures. The imperfect interface of the fracture is modeled with saw-tooth-like structures. The defined saw-tooth-like structures of contact asperities impose an in-plane asymmetry in the shear direction. The compliance ratio of the rough fracture is larger than the compliance ratio of the smooth fracture. Interlocking and riding …

Design Of Surface Texture For The Enhancement Of Tribological Performance, Cong Shen

LSU Doctoral Dissertations

Surface texturing is a method of surface modification that fabricates micro patterns on the contacting surfaces to improve the tribological performance in sliding, lubricated system. It is found that the geometric design of textures has a significant influence on the performance of textured surfaces. Some important geometric parameters, such as the area ratio and the depth-over-diameter ratio, have been identified for textures in the form of circular dimples. The current study aims to improve the friction reduction effect of surface texturing by using textures with novel designs. Some new factors considered in the design of textures are: internal structure and …

Nano Cost Nano Patterned Template For Surface Enhanced Raman Scattering (Sers) For In-Vitro And In-Vivo Applications, Hsuan-Chao Hou

LSU Doctoral Dissertations

Raman scattering is a well-known technique for detecting and identifying complex molecular level samples. The weak Raman signals are enormously enhanced in the presence of a nano-patterned metallic surface next to the specimens. This dissertation describes a technique to fabricate a novel, low cost, high sensitive, disposable, and reproducible metallic nanostructure on a transparent substrate for Surface Enhanced Raman Scattering (SERS). Raman signals can be obtained from the specimen surface of opaque specimens. Most importantly, the metallic nanostructure can be bonded on the end of a probe / a needle, and the other end is coupled to a distant spectrometer. …

Powers And Compensation In Three-Phase Systems With Nonsinusoidal And Asymmetrical Voltages And Currents, Prashanna Dev Bhattarai

LSU Doctoral Dissertations

A contribution to power theory development of three-phase three-wire systems with asymmetrical and nonsinusoidal supply voltages is presented in this dissertation. It includes: • contribution to explanation of power related phenomena • contribution to methods of compensation The power equation of unbalanced Linear Time Invariant (LTI) loads at sinusoidal but asymmetrical voltage is first presented. The different current components of such a load and the phenomenon associated with these current components are described. The load current decomposition is used for the design of reactive balancing compensators for power factor improvement. Next, the current of LTI loads operating at nonsinusoidal asymmetrical …

Antibacterial Properties Of Poly (Octanediol Citrate)/Gallium-Containing Bioglass Composite Scaffolds, Ehsan Zeimaran, Sara Pourshahrestani, Ivan Djordjevic, Belinda Pingguan-Murphy, Nahrizul Adib Kadri, Anthony W. Wren, Mark R. Towler

Chemical and Biochemical Engineering Faculty Research & Creative Works

Bioactive glasses may function as antimicrobial delivery systems through the incorporation and subsequent release of therapeutic ions. The aim of this study was to evaluate the antimicrobial properties of a series of composite scaffolds composed of poly (octanediol citrate) with increased loads of a bioactive glass that releases zinc (Zn²⁺) and gallium (Ga³⁺) ions in a controlled manner. The antibacterial activity of these scaffolds was investigated against both Gram-positive (Staphylococcus aureus) and Gram-negative (Escherichia coli) bacteria. The ability of the scaffolds to release ions and the subsequent ingress of these ions into hard tissue was evaluated …

Inorganic Hemostats: The State-Of-The-Art And Recent Advances, Sara Pourshahrestani, Ehsan Zeimaran, Ivan Djordjevic, Nahrizul Adib Kadri, Mark R. Towler

Chemical and Biochemical Engineering Faculty Research & Creative Works

Hemorrhage is the most common cause of death both in hospitals and on the battlefield. The need for an effective hemostatic agent remains, since all injuries are not amenable to tourniquet use. There are many topical hemostatic agents and dressings available to control severe bleeding. This article reviews the most commonly used inorganic hemostats, subcategorized as zeolite and clay-based hemostats. Their hemostatic functions as well as their structural properties that are believed to induce hemostasis are discussed. The most important findings from in vitro and in vivo experiments are also covered.

Applying Dijkstra Algorithm For Solving Neutrosophic Shortest Path Problem, Florentin Smarandache, Luige Vladareanu, Said Broumi, Assia Bakali, Muhammad Akram

Branch Mathematics and Statistics Faculty and Staff Publications

The selection of shortest path problem is one the classic problems in graph theory. In literature, many algorithms have been developed to provide a solution for shortest path problem in a network. One of common algorithms in solving shortest path problem is Dijkstra’s algorithm. In this paper, Dijkstra’s algorithm has been redesigned to handle the case in which most of parameters of a network are uncertain and given in terms of neutrosophic numbers. Finally, a numerical example is given to explain the proposed algorithm.

A Microfluidic-Based Tactile Sensor For Palpating Mice Tumor Tissues, Yichao Yang, Garett Johnson, Dean Krusienski, Siqi Guo, Cheng Lin, Zhili Hao

Mechanical & Aerospace Engineering Faculty Publications

In light of the need of tissue palpation for Robotics-assisted Minimally Invasive Surgery (RMIS), this paper presents a microfluidic-based tactile sensor for palpating mice tissues for tumor localization. The core of the sensor is a 3x3 sensing-plate/transducer array built into a single polydimethylsiloxane (PDMS) microstructure, with a transducer spacing of 3.75mmx1.5mm. Mounted on a robot, the sensor is pressed against a tissue region with a pre-defined indentation depth pattern, and consequently the stiffness distribution across the tissue region translates to the deflection distribution of the sensing-plate array and is captured by the transducer array underneath as resistance changes. Thus, the …

Heuristic And Exact Algorithms For The Two-Machine Just In Time Job Shop Scheduling Problem, Mohammed Al Salem, Leonardo Bedoya-Valencia, Ghaith Rabadi

Engineering Management & Systems Engineering Faculty Publications

The problem addressed in this paper is the two-machine job shop scheduling problem when the objective is to minimize the total earliness and tardiness from a common due date (CDD) for a set of jobs when their weights equal 1 (unweighted problem). This objective became very significant after the introduction of the Just in Time manufacturing approach. A procedure to determine whether the CDD is restricted or unrestricted is developed and a semirestricted CDD is defined. Algorithms are introduced to find the optimal solution when the CDD is unrestricted and semirestricted. When the CDD is restricted, which is a much …

Panic That Spreads Sociobehavioral Contagion In Pedestrian Evacuations, Terra Elzie, Erika Frydenlund, Andrew J. Collins, R. Michael Robinson

VMASC Publications

Crowds are a part of everyday public life, from stadiums and arenas to school hallways. Occasionally, pushing within the crowd spontaneously escalates to crushing behavior, resulting in injuries and even death. The rarity and unpredictability of these incidents provides few options to collect data for research on the prediction and prevention of hazardous emergent behaviors in crowds. This study takes a close look at the way states of agitation, such as panic, can spread through crowds. Group composition—mainly family groups composed of members with differing mobility levels—plays an important role in the spread of agitation through the crowd, ultimately affecting …

Towards A Systems Theory-Based Curriculum For Complex Systems Governance, Polinpapilinho Katina, Joseph M. Bradley

Engineering Management & Systems Engineering Faculty Publications

The purpose of this paper is to explore challenges associated with the development of a curriculum for an emerging field of Complex System Governance (CSG) that could be used for instruction and teaching leaders, managers, and students interested in increasing their knowledge, skills, and abilities about CSG. CSG has been suggested as a means to (1) expose deep system issues impacting performance, (2) introduce practitioners to new thinking, technologies, tools, and methods to address these issues, and (3) institutionalize capabilities to continuously advance governance. As with all new approaches, a curriculum in an emerging field is an essential element for …

Forced Convection Cooling Of Electric Motors Using Enhanced Surfaces, Mohammed Almaghrabi

Electronic Theses and Dissertations

Electric motors are extensively engaged in industrial and commercial applications such as electrical cars, energy-conversion systems, elevators, and actuators for aircrafts. Due to the significant internal heat generation, it is usually a challenge to design and manufacture high power density, high reliability, and low cost electric motors with superior performance. One of the efficient ways to dissipate the heat generated in the electrical motor is by using extended surfaces (i.e. heat sinks). These surfaces are extruded from the motor casing and air is forced though them by a cooling fan. This cooling approach is simple to be implemented and has …

Assessing Public Health Burden Associated With Exposure To Ambient Black Carbon In The United States, Ying Li, Daven K. Henze, Darby Jack, Barron H. Henderson, Patrick L. Kinney

ETSU Faculty Works

Black carbon (BC) is a significant component of fine particulate matter (PM_2.5) air pollution, which has been linked to a series of adverse health effects, in particular premature mortality. Recent scientific research indicates that BC also plays an important role in climate change. Therefore, controlling black carbon emissions provides an opportunity for a double dividend. This study quantifies the national burden of mortality and morbidity attributable to exposure to ambient BC in the United States (US). We use GEOS–Chem, a global 3-D model of atmospheric composition to estimate the 2010 annual average BC levels at 0.5 x 0.667° …

Can You Hack It? Validating Predictors For It Boot Camps, Courtney Gear

All Graduate Theses, Dissertations, and Other Capstone Projects

Given the large number of information technology jobs open and lack of qualified individuals to fill them, coding boot camps have sprung up in response to this skill gap by offering a specialized training program in an accelerated format. This fast growth has created a need to measure these training programs and understand their effectiveness. In the present study, a series of analyses examined whether specific or combinations of predictors were valid for training performance in this coding academy. Self-rated, daily efficacy scores were used as outcome variables of training success and correlation results showed a positive relationship with efficacy …

Use Of Bridging Strategy Between The Ensemble Kalman Filter And Particle Filter For The Measurements With Various Quasi-Gaussian Noise, Sumathi Prabhakaran Jeyakumari

All Graduate Theses, Dissertations, and Other Capstone Projects

Filtering and estimation are two important tools of engineering. Whenever the state of the system needs to be estimated from the noisy sensor measurements, some kind of state estimator is used. If the dynamics of the system and observation model are linear under Gaussian conditions, the root mean squared error can be computed using the Kalman Filter. But practically, noise frequently enters the system as not strictly Gaussian. Therefore, the Kalman Filter does not necessarily provide the better estimate. Hence the estimation of the nonlinear system under non-Gaussian or quasi-Gaussian noise is of an acute interest. There are many versions …

Rubber Roads For The Rubber City: Testing The Suitability Of Rubberized Asphalt For Roads In Northeast Ohio, Jessica M. Fraser

Williams Honors College, Honors Research Projects

This research paper explores the benefits of using rubberized asphalt concrete (RAC) versus normal asphalt concrete (NAC) and why it is environmentally important. New road construction and repair of roadways due to potholes are always occurring in Northeast Ohio. Recently, the city of Akron’s transportation budget has increased, which includes projects such as reconstructing asphalt and resurfacing pavements throughout the city of Akron. Using rubberized asphalt may improve the quality of our roads and reduce roadway degradation which will likely save cities money.

Using rubberized asphalt recycles old tires, which do not decompose, and creates a positive use for them …

Wettability Of Magnesium Based Alloys, Victor Manuel Ornelas

Open Access Theses & Dissertations

The premise of this project was to determine the wettability behavior of Mg-based alloys using three different liquids. Contact angle measurements were carried out along with utilizing the Zisman method for obtaining values for the critical surface tension. Adhesion energy values were also found through the use of the Young-Dupre equation. This project utilized the Mg-based alloy Mg-2Zn-2Gd with supplemented α-Minimum Essential Medium (MEM), Phosphate Buffer Saline solution (PBS), and distilled water. These three liquids are commonly used in cell cultivation and protein adsorption studies. Supplemented α-MEM consisted of α-MEM, fetal bovine serum, and penicillin-streptomycin. Mg-2Zn-2Gd was used because of …

Stem Cell Induction Via Inkjet-Mediated Gene Transfection, Gilbert Paquian Jr.

Open Access Theses & Dissertations

In 2009 and 2011, it was shown that micropores in the cell membrane that form during inkjet cell printing are a potential vector for gene transfection1,2. These papers showed that porcine aortic endothelial cells and Chinese hamster ovary cells were coprinted with green fluorescent protein-coding (GFP) plasmids onto collagen or gelatin "biopaper" substrates. Printed cells showed a viability of ~90% with transfection efficiencies ranging from 2-30%1,2. Using inkjet-mediated gene transfection (IMGT) to insert a plasmid coding for the Yamanaka stem cell induction factors, it may be possible to offset common drawbacks of the induction process, such as low efficiency, throughput, …

Optimal Energy Management System For A Net Zero Building Using Multi-Agent Systems Approach, Arzhang Ghassemi Pashakalaei

Open Access Theses & Dissertations

Buildings have a significant impact on energy usage and the environment. Much of the research in architectural sustainability has centered on economically advanced countries because they consume the most energy and have the most resources. However, sustainable architecture is important in developing countries, where the energy consumption of the building sector is increasing significantly. The aims of this Thesis are investigating using the hybrid system, which formed by interconnecting two source of renewable energy as solar (PV arrays) and wind (turbine) along with city grid for compensation purposes wherever it is required. In this Thesis, after literature review, we consider …

Application Of Secondary Analyses On Industrial Data Sets, Luis G. Perez

Open Access Theses & Dissertations

Secondary analysis on quantitative data sets is the in-depth analysis of relationships, trends, patterns or behaviors that are not obvious from a superficial examination of data but that can be very germane in the application of that data. The present work presents a framework for investigators to use in applying secondary analysis on big data that correlates to the research topic. The framework can facilitate the illumination of possible data behaviors or patterns that could be useful in arriving at an answer to a question. Behavior of monitored equipment (analyzers, meters, etc.) can easily be depicted and can be used …

Evaluation Of Point Of Use Reverse Osmosis Systems For Drinking Water In Colonias, Oscar Daniel Ramirez

Open Access Theses & Dissertations

Clean drinking water is often considered a right and not a privilege, especially in first world countries. However, thousands of residents of colonias (settlements in the U.S. that lack access to basic infrastructure) struggle to obtain clean drinking water, including some in the Paso del Norte Region. Residents of colonias located in Doña Ana County, NM, and El Paso County, TX typically rely on domestic wells and hauled water, respectively, but these sources may be of inadequate quality, potentially posing a health risk due to microbiological contamination, presence of arsenic, or elevated concentration of total dissolved solids. This project brings …