Engineering Commons^™

Study Of Control Schemes For Series Hybrid-Electric Powertrain For Unmanned Aerial Systems, Darren A. Dehesa Jr

LSU Master's Theses

Hybrid-Electric aircraft powertrain modeling for Unmanned Aerial Systems (UAS) is a useful tool for predicting powertrain performance of the UAS aircraft. However, for small UAS, potential gains in range and endurance can depend significantly on the aircraft flight profile and powertrain control logic in addition to the subsequent impact on the performance of powertrain components. Small UAS aircraft utilize small-displacement engines with poor thermal efficiency and, therefore, could benefit from a hybridized powertrain by reducing fuel consumption. This study uses a dynamic simulation of a UAS, representative flight profiles, and powertrain control logic approaches to evaluate the performance of a …

Characterizing The Biophysical Properties And Origin Of Extracellular Matrix In The Breast Tumor Microenvironment, Connor T. King

LSU Master's Theses

Tumors derived from breast tissue possess the ability to manipulate and permanently alter their surrounding tissue. Studies demonstrate that tissues surrounding breast tumors have differences in secreted factors as well as extracellular matrix (ECM) deposition and structure. However, some fundamental gaps exist within this paradigm: specifically, what exacerbates this transformation and are these changes maintained between the subtypes of breast tumors? Therefore, a targeted evaluation of the effects of the tumor on the stromal microenvironment in a subtype specific manner will be invaluable. To determine if tumor aggressiveness and subtype differentially regulate the tumor microenvironment, a model must be constructed …

On The Stress Concentration At Sharp V-Notches Under Tension, Trent Mattieu Andrus

LSU Master's Theses

Accurately determining stresses at re-entrant corners using finite element analysis (FEA) is challenging due to the high stresses produced at the corner. Indeed, FEA is unable to obtain quantitatively accurate peak stresses at mathematically sharp re-entrant corners with traditional boundary conditions because these stresses are singular. Imposing a local corner radius by rounding the sharp corner to remove the singular result is an appropriate technique for large radii, but as the corner radius tends to zero and the notch is close to being sharp, we expect there are radii that yield quantitatively inaccurate results with traditional FEA. We seek to …

Modulating Mechanical Properties Of Polymer Composites Via Colloidal Particle Reinforcement, Yusheng Guo

LSU Master's Theses

Additive manufacturing allows the rapid process of complex objects with excellent design flexibility. However, the products often exhibit poor mechanical properties when pure polymer is applied as printable material. In this work, we demonstrate that printability of polymer can be dramatically improved when particle filler is added to form reinforced polymer composites. Furthermore, the interaction between filler and polymer matrix leads to the enhancement in mechanical properties of the printed product. The material reinforcement induced by addition of fillers enables the wide application of polymer composites to print structures with unique features. In the printing of silica-reinforced pNIPAM composite, we …

Developing A Competency Model For Highway Safety Engineers: A Delphi Method, Garrett K. Wheat

LSU Doctoral Dissertations

The primary purpose of this study was to determine the core competencies needed by State DOT Highway Safety Engineers as perceived by Highway Safety experts in the United States. First, a list of competencies was identified. Next, a panel of Highway Safety experts determined the importance of each identified competency for the current year (2020) and for the future (year 2030). Finally, ratings provided by the panel were tested for the presence of consensus.

For this study, the researcher used a Delphi Method as classified by Delbecq, Van de Ven, and Gaustafson (1975). Through this method, a panel of forward-thinking …

Optimizing The Performance Of Multi-Threaded Linear Algebra Libraries Based On Task Granularity, Shahrzad Shirzad

LSU Doctoral Dissertations

Linear algebra libraries play a very important role in many HPC applications. As larger datasets are created everyday, it also becomes crucial for the multi-threaded linear algebra libraries to utilize the compute resources properly. Moving toward exascale computing, the current programming models would not be able to fully take advantage of the advances in memory hierarchies, computer architectures, and networks. Asynchronous Many-Task(AMT) Runtime systems would be the solution to help the developers to manage the available parallelism. In this Dissertation we propose an adaptive solution to improve the performance of a linear algebra library based on a set of compile-time …

Parallel And Asynchronous Distributed Optimization For Power Systems Operation, Ali Mohammadi

LSU Doctoral Dissertations

Distributed optimization approaches are gaining more attention for solving power systems energy management functions, such as optimal power flow (OPF). Preserving information privacy of autonomous control entities and being more scalable than centralized approaches are two primary reasons for developing distributed algorithms. Moreover, distributed/ decentralized algorithms potentially increase power systems reliability against failures of components or communication links.

In this dissertation, we propose multiple distributed optimization algorithms and convergence performance enhancement techniques to solve the OPF problem. We present a multi-level optimization algorithm, based on analytical target cascading, to formulate and solve a collaborative transmission and distribution OPF problem. This …

Using Spatial Analysis And Machine Learning Techniques To Develop A Comprehensive Highway-Rail Grade Crossing Consolidation Model, Samira Soleimani

LSU Doctoral Dissertations

The safety of highway-railroad grade crossings (HRGC) is still an issue in the United States of America (USA). The grade crossing is where a railroad crosses a road at the same level without any over or underpass. To improve the safety of crossings, the crossings’ condition should be explored from several aspects such as engineering design (speed limit, warning signs, etc.), road condition (number of lanes, surface markings, etc.), rail design (the type of track, ballast, etc.), temporal variables (weather, visibility, time of day, lightning, etc.), social variables (population, race, etc.), and last but not least, spatial variables (the type …

Secure High Der Penetration Power Distribution Via Autonomously Coordinated Volt/Var Control, Anto Joseph, Keyue Smedley, Shahab Mehraeen

Faculty Publications

Traditionally voltage control in distribution power system (DPS) is performed through voltage regulating devices (VRDs) including on load tap changers (OLTCs), step voltage regulators (SVRs), and switched capacitor banks (SCBs). The recent IEEE 1547-2018 from March 2018 requires inverter fed distributed energy resources (DERs) to contribute reactive power to support the grid voltage. To accommodate VAR from DERs, well-organized control algorithm is required to use in this mode to avoid grid oscillations and unintended switching operations of VRDs. This paper presents two voltage control strategies (i) static voltage control considering voltage-reactive power mode (IEEE 1547-2018), (ii) dynamic and extensive voltage …

Development, Education, And Implementation Of A Low-Cost Audio Sensor-Based Autonomous Surveillance System For Smart And Connected Transportation Infrastructure Construction And Maintenance, Yong-Cheol Lee, Jin-Woo Choi Ph.D

Publications

Each DOT has to govern and oversee an enormous number of transportation construction and maintenance projects. However, since a transportation construction project entails several miles of a job site including numerous work tasks and equipment operations, it has been increasingly challenging for each DOT to consistently monitor progress of all projects in each State as well as efficiently evaluate work performance. In particular, with limited human resources and time, DOTs in Region 6 States have managed large-scale transportation construction and maintenance projects by a human inspection and recovered direct and indirect damages of transportation infrastructure systems caused from the recent …

Real-Time Work Zone Traffic Management Via Unmanned Air Vehicles, Charles Malveaux Ph.D, Marcio De Queiroz Ph.D, Xin Li Ph.D, Hany Hassan Ph.D, Zewei He Ph.D

Publications

Highway work zones are prone to traffic accidents when congestion and queues develop. Vehicle queues expand at a rate of 1 mile every 2 minutes. Back-of-queue, rear-end crashes are the most common work zone crash, endangering the safety of motorists, passengers, and construction workers. The dynamic nature of queuing in the proximity of highway work zones necessitates traffic management solutions that can monitor and intervene in real time. Fortunately, recent progress in sensor technology, embedded systems, and wireless communication coupled to lower costs are now enabling the development of real-time, automated, “intelligent” traffic management systems that address this problem. The …

Abq Streets: Creating Alternative Residential Street Designs, Gregory Rowangould Ph.D, Nick N. Ferenchak Ph.D

Publications

This research evaluates opportunities for retrofitting residential streets with alterative designs with the overall goal of improving their function, reducing their negative impacts and reducing maintenance costs. This is accomplished through three main research tasks. First, we conduct a comprehensive review of the street design literature with a focus on studies that report how alterative or unique designs that are relevant to the residential street context affect travel behavior, traffic flow, safety, crime and environmental impacts. We then survey residential streets in several study neighborhoods to measure typical design features and cross sections. With this information we then evaluate which …

Selecting The Most Feasible Construction Phasing Plans For Urban Highway Rehabilitation Projects, Kunhee Choi Ph.D, H. David Jeong Ph.D, Yong-Cheol Lee, Yangtian Yin

Publications

Despite the abundance of research that has aimed to understand the effects of highway work zones, very little definitive information is available concerning the determination of work zone length (WZL). Quantitative studies that holistically model WZL are very rare. To fill this gap, this study identifies critical factors affecting WZL and develops decision support models that determine the optimal WZL in a balanced tradeoff between motorists’ inconvenience due to traffic disruption and their opportunity cost. A high-confidence dataset was created by conducting a series of scheduling and traffic simulations and analyses. The results revealed that traffic loading and work zone …

Detection And Estimation Of Inundation And Associated Risks Using Traffic And Monitoring Cameras And Image Processing Under Extreme Flooding Conditions, Suyun Ham Ph.D, Seongjin Noh Ph.D, Dong-Jun Seo Ph.D, Yin Chao Yu, Sangoo Kang

Publications

The main objective of this project is to develop an inundation detection and evaluation framework using images from traffic monitoring cameras and reliable flood monitoring under extreme precipitation conditions. This study presents a comparative assessment of image enhancement and segmentation techniques to automatically identify the flash flooding from the low-resolution images taken by traffic-monitoring cameras. Due to inaccurate equipment in severe weather conditions (e.g., raindrops or light refraction on camera lenses), low-resolution images are subject to noises that degrade the quality of information. De-noising procedures are carried out for the enhancement of images by removing different types of noises. After …

Assessment Of Compatibility Of Mineral Aggregates And Binders Used In Highway Construction And Maintenance Projects, Zahid Hossain Ph.D, Ashraf Elsayed Ph.D, Tandra Bagchi, Sumon Roy

Publications

Stripping and delamination have been deemed as some of the major premature pavement distresses to most state Departments of Transportations (DOTs) and highway agencies including the Arkansas Department of Transportation (ARDOT). It is believed that the poor compatibility between asphalt binders and aggregates is one of the major reasons behind this. This study aims to analyze the compatibility of selected asphalt binders and aggregates used in Arkansas. Asphalt binders used in this study include PG 64-22, PG 70-22, and PG 76-22; each prepared from two different crude courses. Additionally, four different types of aggregates (sandstone, limestone, gravel, and dolomite) from …

Optimizing The Geometric Configuration And Manufacturing Process Of High Mast Illumination Poles, Arturo Montoya Ph.D, Adolfo Matamoros Ph.D, Reza Nasouri, Echizeni Ikpah, Arsalan Majlesi

Publications

This work presents the development of a high-fidelity model that accounts for the cumulative effect of welding and hot- dip galvanizing on the determining the resulting residual stresses and deformations induced during the manufacturing process of high mast illumination poles (HMIPs). This model is meant to elucidate the root causes of weld toe cracks in HMIPs. A TxDOT pole-to-base plate connection detail was used as the reference model in the analysis. Welding was modeled using the plug-in Abaqus Welding Interface (AWI), which automatically implements a series of sequential thermal and mechanical analyses. Then, the welding stress results were used as …

Seismic Ground Motion Data Analyses For North-East Arkansas, Zahid Hossain Ph.D, Ashraf Elsayed Ph.D, Md Ariful Hasan, Md Rafiue Islam

Publications

Estimation of liquefaction resistance and shear velocities are key elements in the assessment of potential earthquake damage of existing and new construction sites. The Arkansas Department of Transportation (ARDOT) and other agencies in the region need ground motion response analysis (GMRA) data of specific construction sites. As part of a recent ARDOT’s Transportation Research Committee (TRC) project, researchers have conducted geophysical investigations several construction sites in northeast Arkansas over the past twelve years. The current study gathered the previously reported test data and estimated seismic hazard properties such as shear wave velocity profiles and seismic hazard coefficients for nearby locations. …

Real-Time Early Detection And Monitoring Of Flooding Using Low-Cost Highly Sensitive Ultrasound Sensing Of Water Level, Suyun Ham Ph.D, Seongjin Noh Ph.D, Dong-Jun Seo Ph.D, Sanggoo Kang, Dafnik Saril Kumar David

Publications

Flooding poses safety hazards to motorists, emergency and maintenance crews and may cause costly damage to transportation infrastructure and its operation. Flash flooding, in particular, causes the most flood-related deaths According to NOAA, in 2017 alone, flash flooding also caused $60.7 billion worth of economic damage. Low-water crossings are among the first places where deaths and significant damages to vehicles occur during flooding. With flash flooding, when a critical corridor is blocked by a high level of water, it affects the safety of the general public. To keep the critical corridors open as long as possible, and to minimize losses …

Analysis Of The Causes Of Workforce Shortages: Create Guidelines For Education And Workforce Development In Transportation To Generate Future Careers For The Navajo Nation, Gholam Ehteshami

Publications

Activities were dedicated to the collections, summarizations and categorizing more research articles related to the analysis of the sources of workforce deficiencies. The focus was on the technical and educational solution methods and strategies, guideline relevant to the workforce development. The times also were committed to the development of educational modules related to carrier’s opportunities in the transport industry into a couple of courses. Several NTU STEM students were interviewed, selected and introduced for the summer research internships in transportation areas to LSU Tran SET center. Outreach activities conducted with the community and some of the high school professionals related …

The Impacts Of Increased Adverse Weather Events On Freight Movement, Kyung "Kate" Hyun Ph.D, Stephen P. Mattingly Ph.D, Mehrdad Arabi

Publications

Freight transportation is a major economic backbone of the United States and is vital to sustaining the nation’s economic growth. Ports, as one of the primary components of freight transportation and important means of integrating into the global economic system, have experienced significant growth and increased capacity during the past two decades. The study addresses an important national freight mobility goal to enhance the resilience of the port transportation operations in the event of extreme weather events. This study develops an adaptable resilience assessment framework that evaluates the impact of a disruptive event on transportation operations. The framework identifies dynamic …

Enhancing Evaluation Of Wildlife Detection Systems, Nick N. Ferenchak Ph.D

Publications

Every year in the United States, wildlife-vehicle collisions (WVCs) cause 200 human fatalities, 26,000 human injuries, and substantial harm to wildlife populations, resulting in approximately $8.4 billion in total costs. The research team examined two US 64 bridges located near Lumberton, New Mexico that were designed to allow wildlife to cross underneath. Monitoring stations were positioned at each of the crossings so that both wildlife approaches and passages were observed. Special mounting brackets were designed and fabricated to allow for the installation of monitoring equipment. Wildlife observations were supplemented with WVC counts. Over seven months of study, nearly 100,000 wildlife …

Eco-Friendly Stabilization Of Sulfate-Rich Expansive Soils Using Geopolymers For Transportation Infrastructure, Xinbao Yu, Anand Puppala, Miladin Radovic, Sayantan Chakraborty, Jungyeon Jang, Oscar Huang

Publications

Traditional calcium-based stabilizers, such as lime, to stabilize sulfate-rich expansive soils, are lasting-challenges in geotechnical engineering. The biggest problem with using calcium-based stabilizers is that when calcium and water are exposed to sulfate-rich expansive soils, they form ettringite as an expansive mineral, which causes sulfate-induced heaving. The study aimed to investigate the feasibility of stabilizing sulfate-rich expansive soils using geopolymers for transportation infrastructure. Literature review on sulfate-induced heaving and sulfate-rich soils stabilized with geopolymers suggests a direction for how to stabilize sulfate soils using geopolymers. The engineering tests were conducted to determine the swell, shrinkage, and strength behavior of natural, …

Influence Of Powder Activated Carbon (Pac) In Fly Ash On The Properties Of Concrete, Zahid Hossain, Sumon Roy

Publications

Class C Fly Ash (CFA) is commonly used as supplementary cementitious material (SCM) in producing concrete by ready-mix concrete contractors in Arkansas. However, CFA can be used as a partial replacement of Ordinary Portland Cement (OPC) if it meets certain ASTM requirements. It is believed that the presence of powder activated carbon (PAC) in CFA increases the demand of the air-entraining agent (AEA) to achieve specified air content, and this is a concern to transportation agencies such as the Arkansas Department of Transportation (ARDOT) and concrete producers in recent years. Thus, the main goal of this research is to assess …

Life Cycle Environmental Impact Of Houston Metro System – Evaluation Of Electric Alternatives, Raghava R. Kommalapati Ph.D, Hongbo Du Ph.D, Doeun Choe Ph.D

Publications

In the Greater Houston Area, mobile sources (on-and off-road vehicles) contribute the largest share of nitrogen oxide (NOx) emissions and second-highest share of volatile organic (VOC) emissions. The Houston METRO system is a key element in Houston's infrastructure that can be expanded to lower emissions of criteria air pollutants (CAPs) and greenhouse gases (GHGs) and improve regional air quality. Currently, there is no comparative study for relative emissions and environmental impacts between passenger automobiles and METRO routes in Houston. Our research addressed this critical gap and developed environmental life cycle assessment for conventional diesel buses, diesel hybrid buses, and alternative …

Bridge Construction Monitoring Using Lidar For Quantified, Objective Quality-Control Quality-Assurance (Qoqcqa), Fernando Moreu Ph.D, Chris Lippitt Ph.D, Xinxing Yuan

Publications

Transportation infrastructure construction quality control and quality assurance demands construction monitoring by field inspectors. Currently, these inspectors monitor infrastructure by measuring and photographing structures. These tasks allow them to assess any correction decision during construction or to inform about the quality of the construction process for the future. In order to promote and objective decisions obtained during infrastructure construction, the proposed research project developed and implemented a methodology to measure construction progress and compared it with the designed 3D shape, quantifying the difference. This proposed project includes implementation for the development of DOT standards that could be added in near …

Holistic Network-Level Assessment Of Pavement Flood Damages, Yong-Cheol Lee, Kunhee Choi Ph.D, Moeid Shariatfar

Publications

After recent catastrophic flood disasters in Louisiana in 2016 and Texas in 2017, roadways in Region 6 areas suffer not only from the flood-inundation, but also from the long-term recovery processes that incur enormous maintenance costs. To assess the impacts of flooding disasters on roadways, various studies have investigated sampled roadway damages with pavement engineering techniques such as a direct damage analysis using cores/bores. However, current methods are time-consuming and labor-intensive. In addition, even though existing methods provide a detailed damage analysis of pavement in a particular location for a particular time period, there is still a large practical knowledge …

Advanced Modeling And Design Methodology For Pavements Using Plasticity-Based Shakedown Theory, Shengli Chen, Chao Sun, Xu Wang, Zhiming Zhang

Publications

Pavement design is a process intended to find the most economical combination of layer thickness and material type for the pavement, taking into account the properties of the subgrade soil and the traffic to be carried during the service life of the road. The currently prevalent methods of pavement analysis and design, however, are more or less empirical in U.S., which possess the shortcoming that the important type of pavement distress of rutting related to the accumulation of plastic or permanent deformations cannot be effectively considered. This project proposes an exploratory study on the application of the plasticity theory-based shakedown …

Investigating The Impacts Of Truck Platooning On Transportation Infrastructure In The South-Central Region, Hany Hassan Ph.D, Samer Dessouky, Alireza Talebpour, Md Adilur Rahim

Publications

Truck platooning is an essential application of connected and autonomous vehicles, where several trucks are connected to each other forming a platoon. It is envisioned that truck platooning can assist in minimizing transportation challenges related to freight movements in the US by improving traffic operation, safety and reducing fuel consumption and emission. One of the most valuable truck corridors in the US is in the South-central region. This study investigates the impacts of truck platooning on US highways in that region using both corridor and network-level simulation analysis. Also, the impact of truck platooning on the pavement was quantified using …

Development Of Corrosion Inhibiting Geopolymers Based Cement For Transportation Infrastructure, Homero Castaneda, Miladin Radovic, Changkyu Kim, Oscar Huang

Publications

Geopolymers are gaining attention as affordable, sustainable, and eco-friendly replacement for Ordinary Portland Cement (OPC) in concrete civil structures. More importantly, Geopolymer-based Cement (GPC) provide sustainable and environmentally friendly alternative to OPCs as GPC can be processed at room temperatures from aqueous solutions of waste materials (e.g., fly ash) or abounded natural sources (e.g., clay) and thus reduce significant CO₂ production associated with processing of OPC. Although, a lot of work has been done on improving mechanical properties of GPC over the last two decades, there are only a few studies on effects of GPC concrete on steel rebar …

On The Recovery And Fatigue Life Extension Of Stainless Steel 316 Metals By Means Of Recovery Heat Treatment, Ali Haghshenas, M. M. Khonsari

Faculty Publications

In this paper, we propose a methodology for enhancing the fatigue life of SS316 by performing intermittent recovery heat-treatment (RHT) in the Argon environment at different temperatures. To this end, fully-reversed fatigue bending tests are conducted on the heat-treated SS316 specimens. Damping values are obtained using the impact excitation technique to assess the damage remaining in the material after each RHT and the corresponding fatigue life. Damping is also used to distinguish the three stages of the fatigue phenomenon and the onset of crack initiation. The results show that by performing intermittent RHTs, the density of dislocation is decreased substantially …