Engineering Commons^™

Porcine Neonatal Heart Extracellular Matrix As A Regeneration Platform, Karla Perez

Bioengineering Dissertations - Archive

Each year, an estimated 620,000 Americans have new heart attack and suffer from myocardial infarction (MI) that results in massive heart cell death and decrease in heart function. Various therapeutic strategies, such as pharmacological treatments and reperfusion strategies, have greatly improved short-term MI survival. However, these strategies do not restore normal cardiac function due to the permanent loss of cardiomyocytes. As a promising strategy, cardiac cell therapy delivers repairing cells to damaged areas (scar tissues) to revitalize the infracted heart. However, a key challenge in cardiac cell therapy, i.e. the extremely low survival and engraftment rate of transplanted cells, must …

Environmental And Health Implications Of Mine Tailing-Based Construction Materials In Developing Communities: Current Practices And Ways Forward, Jose Raul Velasquez Vasquez

Civil Engineering Theses - Archive

For many years, artisanal and small-scale mining (ASM) communities around the world have been developing strategies to reduce contaminated mine tailings produced by mineral processing operations. These mine tailings are the by-product of the physical and chemical processes required to extract metals that humans require every day. The strategies developed by these communities cover a wide range of solutions, such as better practices in mineral processing activities as well as alternative technologies that help reduce the environmental impact of mining. Specifically, the recycling of mine tailings to produce construction materials has been of interest to researchers and communities. The use …

A New Geothermal Bridge De-Icing System With Attached Hydronic Heating Loops: Field Tests, Numerical Modeling, And Economic Assessment, Omid Habibzadeh Bigdarvish

Civil Engineering Dissertations - Archive

Each year, ice and snow adversely impact U.S. transportation infrastructure during the cold season, causing an extensive impact on the U.S. economy. Bridges are key elements in the transportation network and the most vulnerable sections of the road to ice and snow. Conventional snow and ice removal system (CSRS) is proven not to be a satisfactory solution as it causes induced damages and issues, such as accelerating bridge deck corrosion, safety issues, travel delays, and environmental damages. Thus, the geothermal heat pump de-icing system (GHDS) is introduced as a sustainable solution for bridge deck de-icing, which utilizes renewable geothermal energy …

Further Development Of Ultra-High-Performance Fiber Reinforced Concrete (Uhp-Frc): 3d Printing, Sifcon, Alternative Fibers, Shrinkage Crack Control, High Temperature, And Lightweight, Bhupendra Raj Acharya

Civil Engineering Theses - Archive

Introduction of artificial intelligence (AI) and machine learning in manufacturing industry also in every service industry, decreasing conventional skilled workforce and stagnated construction industry, probability and past statistics of the accident at the construction sites and difficulty in quality control has led the researchers to think of the solution and alternatives of the conventional construction. A new construction paradigm, known as 3-D concrete printing or additive manufacturing of concrete (AMC) provides such a solution. This research focuses on a preliminary study in 3d printed ultra-high-performance fiber-reinforced concrete (UHP-FRC) and, has developed a novel mix that has balanced extrude-ability and buildability. …

Space-Charge Limited Current In Planar And Cylindrical Crossed-Field Diodes Using Variational Calculus, Adam M. Darr, Ranajoy Bhattacharya, Jim Browning, Allen L. Garner

Electrical and Computer Engineering Faculty Publications and Presentations

No abstract provided.

Characterization And Enhancement Of Mechanical Properties In Thermoplastic Fff Parts Using In-Situ Annealing, Rhugdhrivya Rane

Mechanical and Aerospace Engineering Dissertations - Archive

Fused filament fabrication is one of the most common and widely used additive manufacturing techniques. Owing to its ease of use, availability and cheap feedstock it provides a significant advantage over other AM techniques. But these advantages are overshadowed by the fact that FFF parts show high anisotropy and reduced mechanical properties as compared to conventional manufacturing techniques. Literature review of previous research works show multiple approaches to enhance the mechanical properties of FFF parts but each of these techniques have limitations to either the geometries that can be printed or involve complex expensive setups. In one such technique a …

Shape Modeling, Attitude Estimation, And Classification Of Artificial Resident Space Objects (Rso) Using Photometric Light Curves, Katiyayni Balachandran

Mechanical and Aerospace Engineering Dissertations - Archive

Light curve inversion (LCI) has proven valuable in using photometric measurements to optimize various physical parameters of a resident space object (RSO) such as rotational period about its own spin axis, pole orientation and others. Other characteristics such as shape and size are dependent on the surface brightness. To accurately determine size, shape, spin rate, or attitude information of an unresolved resident space object, photometry is required to capture the relatively rapid changes in brightness that these objects can exhibit. LCI has been developed significantly for asteroids, although not fool-proof for artificial RSOs. Satellites and space debris, unlike asteroids, are …

Theoretical And Experimental Analysis And Optimization Of Thermal Conduction In Electrochemical And Latent Heat Energy Storage Systems, Amirhossein Mostafavi

Mechanical and Aerospace Engineering Dissertations - Archive

Phase change materials (PCMs) are used commonly for energy storage purposes. Thermal energy can be stored in a PCM with a variety of configurations such as PCM slabs, cartesian and cylindrical finned systems. Heat transfer in PCM storage systems can be from a heat transfer fluid (HTF) or a heat source at constant temperature to adjacent PCM. The rate of heat transfer is limited by thermal properties. Fin insertion can improve the heat transfer inside the PCM. Chapters 2 and 3 derive and solve the governing energy equations to determine the transient temperature distribution in the PCM due to the …

Reusing Of Recycled Plastic As Pavement Base And Sub-Base Materials, Tanvir Imtiaz

Civil Engineering Dissertations - Archive

A large percentage of waste materials is recycled back into the same product from which they originated. In spite of considerable progress in recycling waste materials generated in urban environments, the materials are sometimes not able to be recycled into the same product due to their quality or technical requirements and are as a result dumped or incinerated. Recycling concrete aggregate (RCCA) and recycled waste plastics are examples of recycled materials that can be used as an alternative to natural aggregates during the construction of newer structures as well as demolition of existing structures like buildings, bridges, and pavements. Materials …

Causes Of Driver Distraction And Incidents At Signalized Intersections, Zannatulferdous Labony

Civil Engineering Dissertations - Archive

Driver distraction causes a major portion of motor vehicle crashes because distractions turn the driver’s attention away from driving the driving task, Intersections represent high risk environments because many conflict points within the intersection exist. At intersections with signalized traffic control, drivers may be more likely to become distracted than at other intersections. While distraction during the red indication may not seem to be a significant concern, this study investigates the role distraction plays in crashes at signalized intersections. Using the SHRP2 naturalistic driving study data, this study focuses on investigating the frequency and types of driver distraction, the causes …

Development Of Non-Prestressed Uhp-Frc Girders For Long-Span Bridges With Dcsr Design Concept And Collapse Assessment Of Smfs With Calibrated Rc And Uhp-Frc Columns Based On Full-Scale Experiments, Seyed Missagh Shamshiri Guilvayi

Civil Engineering Dissertations - Archive

The work presented here is divided in two parts. This summary includes two paragraphs, each summarizing the topics presented in this dissertation. Ultra-high-performance fiber-reinforced concrete (UHP-FRC) is an emerging material and revolutionarily utilize its mechanical properties can offer a new way to design conventional precast prestressed concrete girders. Its ultra-high compressive strength (> 20 ksi) accompanying by exceptional compressive ductility with a maximum useable compressive strain of 0.015–0.03 allow designers to use higher amount of reinforcement. Current design codes (ACI 318 Building Code and AASHTO LRFD Bridge Design Specifications), limits the maximum useable compressive strain, εcu, to 0.003 for conventional …

Rotor Performance Model (Rpm), Chadwick Scott Balfantz

Mechanical and Aerospace Engineering Theses - Archive

Rotorcraft performance modeling is of high interest with multiple industry codes in existence, many of which are high-fidelity and are comprehensive in the analyses that are achievable. Along with the high-fidelity and the comprehensive nature of the industry codes comes an equally high level of complexity in the inputs required to extract meaningful results. The ever-increasing fidelity in the existing codes creates a need for an analysis code that is built to be highly flexible, designed from the top down and implemented from the bottom up in a structured format. The Rotor Performance Model (RPM) was developed to provide high-fidelity …

Shape-Based Time Series Mining For Process Monitoring And Anomaly Detection, Li Zhang

Industrial, Manufacturing, and Systems Engineering Dissertations - Archive

Due to the rapid development of computing and sensing technology, Internet of Things (IoT)-enabled monitoring plays a crucial role for people suffering from cardiac problems. It is important to detect the abnormal ECG cycles during the cardiac monitoring for the early treatment. However, most existing methods focused on the full reading of time series, for the cycle-based time series, it is wasting time to read the whole time series while we can find the characteristic patterns instead. Characteristic patterns named shapelets are time series subsequences, which are explainable and discriminative features that can best classify time series. Shapelet-based classification that …

Attracting Diverse Talent To The Engineering Professions Of 2030 Activity 1 Outcomes, Una Beagon

Conference Papers

As the world’s focus turns to the future and not the present, the engineering profession must respond to the ever increasing need to bring about a sustainable future. The objective of this paper is to support the reform of engineering education by acknowledging and building upon the current awareness and understanding of sustainable development held by key stakeholders in the process.

This paper presents the outcomes of a study involving twelve focus groups with Academics, Employers and Students in four European countries (Denmark, Finland, France and Ireland) as part of the A-STEP 2030 European Project. Based on the findings, it …

Credit Assignment In Multiagent Reinforcement Learning For Large Agent Population, Arambam James Singh

Dissertations and Theses Collection (Open Access)

In the current age, rapid growth in sectors like finance, transportation etc., involve fast digitization of industrial processes. This creates a huge opportunity for next-generation artificial intelligence system with multiple agents operating at scale. Multiagent reinforcement learning (MARL) is the field of study that addresses problems in the multiagent systems. In this thesis, we develop and evaluate novel MARL methodologies that address the challenges in large scale multiagent system with cooperative setting. One of the key challenge in cooperative MARL is the problem of credit assignment. Many of the previous approaches to the problem relies on agent's individual trajectory which …

Language As A Factor In Aviation Accidents And Serious Incidents: A Handbook For Accident Investigators Ed. 2, Elizabeth Mathews, Anthony T. Brickhouse, Joan Carson Ph.D., Enrique Valdes

Handbooks

The purpose of this handbook is to support accident investigators in the identification and consideration of possible language factors in aviation accidents and serious incidents. This handbook provides guidance, background information, and tools that will assist accident investigators in conducting a systematic review of possible language factors.

Machine Learning Framework For Nonlinear And Interaction Relationships Involving Categorical And Numerical Features, Shirish Mohan Rao

Industrial, Manufacturing, and Systems Engineering Dissertations - Archive

Traditionally, physical scientific experiments have been conducted extensively to study and understand the behavior of a process or a system. With the advancement of computing technology in recent years, computer codes and algorithms are used as simulators to replicate behavior of a complex system. Such use of computers to study a system is termed as ‘computer experiments.’ The process involves selecting specific points or runs in the design space in order to maximize information about the system in minimal runs. These computer models are high dimensional and can take a long time to simulate. Metamodels (or surrogate models) built using …

Multi-Player H1 Differential Game Using On-Policy And Off-Policy Reinforcement Learning, Peiliang An

Electrical Engineering Theses - Archive

This work studies a multi-player H-infinity differential game for systems of general linear dynamics. In this game, multiple players design their control inputs to minimize their cost functions in the presence of worst-case disturbances. We first derive the optimal control and disturbance policies using the solutions to Hamilton-Jacobi-Isaacs (HJI) equations. We then prove that the derived optimal policies stabilize the system and constitute a Nash equilibrium solution. Two integral reinforcement learning (IRL) -based algorithms, including the policy iteration IRL and o -policy IRL, are developed to solve the differential game online. We show that the off-policy IRL can solve the …

Wi-Fi-Based Indoor Localization Using Model-Based And Data-Driven Approaches, Ayoub Idelhaj

Electrical Engineering Theses - Archive

This thesis investigates model-based and data-driven approaches for indoor localization using the Received Signal Strength Indicator (RSSI) of Wi-Fi signals. We study multiple model-based indoor localization approaches, including the free space path loss model, the log-distance path loss model, the International Telecommunication Union (ITU) model, and a nonlinear regression model. We examine their indoor localization accuracy using raw RSSI values, and filter RSSI values passed through a Moving Average filter and a Kalman filter. For data driven approaches, we employ a family of Extreme Learning Machine (ELM) algorithms including Basic-ELM, Online Sequential-ELM (OS-ELM), Hierarchical-ELM (H-ELM), and Kernel-ELM (K-ELM), to find …

Mrda-Mgfsnet: Network Based On A Multi-Rate Dilated Attention Mechanism And Multi-Granularity Feature Sharer For Image-Based Butterflies Fine-Grained Classification, Maopeng Li, Guoxiong Zhou, Weiwei Cai, Jiayong Li, Mingxuan Li, Mingfang He, Yahui Hu, Liujun Li

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Aiming at solving the problems of high background complexity of some butterfly images and the difficulty in identifying them caused by their small inter-class variance, we propose a new fine-grained butterfly classification architecture, called Network based on Multi-rate Dilated Attention Mechanism and Multi-granularity Feature Sharer (MRDA-MGFSNet). First, in this network, in order to effectively identify similar patterns between butterflies and suppress the information that is similar to the butterfly's features in the background but is invalid, a Multi-rate Dilated Attention Mechanism (MRDA) with a symmetrical structure which assigns different weights to channel and spatial features is designed. Second, fusing the …

Development Of A Model To Prioritize Inspection And Condition Assessment Of Gravity Sanitary Sewer Systems, Karthikeyan Loganathan

Civil Engineering Dissertations - Archive

Underground utilities and wastewater collection systems deteriorate over time demanding utility owners to involve in continuous revisions and development of their asset management frameworks to maintain the functionality of their assets. In any asset management framework, inspection of an asset and respective condition assessment plays a vital role in successful operation and maintenance of systems. In the United States, closed-circuit television (CCTV) is the commonly used device for inspecting the inner environment of sewer pipes, which considering the large length of pipe inventory in a city, is a relatively expensive and time-consuming process. Therefore, inspection of every individual sanitary sewer …

Structural Performance Of Distressed Cast-In-Place Concrete Bridge Retaining Wall, Karzan Ms Habeeb

Civil Engineering Dissertations - Archive

Cast-In-Place (CIP) concrete retaining walls have been used in the United States widely in the 20th century. CIP concrete walls have additionally proven to be structurally rigid and cost-effective for low backfill height. This type of wall is also sustainable with design service life of 75 years (TxDOT 2014). However, during service, the wall undergoes distressed movements, structural deficiency, and stability related problems. CIP cantilever concrete retaining walls often do not perform as expected, and the walls are affected by construction and/or structural deficiency, which sometimes leads to failure. The current study was inspired by distressed CIP walls located on …

Modeling Of Hydrogen Sulfide Generation And Rates Of Microbial Induced Concrete Corrosion In Manhole Shafts, Sunakshi Hada

Civil Engineering Dissertations - Archive

Manhole shafts can undergo infrastructure failure due to microbially induced concrete corrosion (MICC). Deterioration of the sewer systems by MICC process occurs due to the volatilization of hydrogen sulfide into the gas phase. The volatized hydrogen sulfide gas reacts with oxygen to form sulfuric acid, resulting in concrete corrosion. If optimum conditions are present, 24 mm of concrete loss can occur in 31 months, and the cost of fixing can range from $10-$30 per square foot. Also, if the manholes are not properly maintained, they can cause serious safety hazards, such as manhole lids falling through the structure, streets giving …

Effectiveness Of Recycled Plastic Pin For Improving Bearing Capacity Of Embankment Over Soft Soil, Md Azijul Islam

Civil Engineering Dissertations - Archive

Construction of embankment over soft foundation soils is incredibly a challenging task due to the risk of bearing failure and excessive settlement of foundation soil. Most of the available conventional methods for addressing these problems are either expensive or time-consuming or both. Therefore, research has been striving to develop a sustainable alternative to the current conventional methods. A noble approach to improve the soft foundation soil could be the use of Recycled Plastic Pins (RPP) in combination with geosynthetics. The load transfer efficiency of a geosynthetic-reinforced and RPP supported embankment is influenced by interactions among embankment fill, geosynthetics, and foundation …

Development And Comparison Of Prediction Models For Sanitary Sewer Pipes Condition Assessment Using Multinomial Logistic Regression And Artificial Neural Network., Daniel Ogaro Atambo

Civil Engineering Dissertations - Archive

Sanitary sewer pipes infrastructure system in good condition is essential in providing safe conveyance of the wastewater from homes, businesses, and industries to the wastewater treatment plants. For sanitary sewer pipes to deliver the wastewater to the treatment plants, they must be in good condition. Most of the water utilities have aged sanitary sewer pipes. Water utilities inspect sewer pipes to decide which segments of the sanitary sewer pipes need rehabilitation or replacement. The process of inspecting the sewer pipes is described as condition assessment. This condition assessment process is costly and necessitates developing a model that predicts the condition …

Performance Of Recycled Plastic Pins For Increasing Bearing Capacity Of Foundation Soil, Faria Fahim Badhon

Civil Engineering Dissertations - Archive

Mechanically Stabilized Earth (MSE) walls constructed on unsuitable foundation soil are prone to large deformation and bearing capacity failure. A variety of techniques can be applied to address this issue, such as removal and replacement of existing soil with competent soil, staged construction, dynamic compaction, stone columns, geosynthetic reinforcement. One common traditional approach followed by Texas Department of Transportation (TxDOT) for the improvement of unsuitable foundation soil is removal of the in-situ soil and replacement with suitable fill material. However, this method can be time-consuming and expensive. A pile-supported system in combination with geosynthetic reinforcement can provide a sustainable solution …

Agent-Based Model Simulation For Police Deployment Decision-Making In Patrol Operations, Yasaman Ghasemi

Industrial, Manufacturing, and Systems Engineering Dissertations - Archive

Police patrolling plays a key role in responding to 911 calls and reducing crimes. The effectiveness of patrol operations heavily depends on the deployment of police officers – e.g., the number of officers assigned to specific policing districts or beats. The complex nature of the policing system – dynamic and stochastic criminal behavior, compounded with limited policing resources, render current (traditional) police operations, which are often managed in a reactive and stationary manner – often makes it very challenging to manage and control. This study develops an agent-based simulation framework to address the dynamically changing environment in police operations and …

Evaluating The Safety Cultures Of Kentucky Transportation Cabinet Maintenance Crews, Ashtarout Ammar, Zamaan Al-Shabbani, Hala Nassereddine, Chris Van Dyke, Gabriel B. Dadi

Kentucky Transportation Center Research Report

Highway work zones can be dangerous and unpredictable. Between 2003 and 2017, over 1,800 workers died on road construction sites. Eliminating injuries and deaths requires state transportation agencies to adopt robust safety cultures as there is a clear relationship between these cultures and worker behaviors. The Kentucky Transportation Cabinet (KYTC) is committed to improving safety performance by nurturing a positive safety climate among highway maintenance crews. To understand the safety cultures of KYTC maintenance crews, researchers administered a survey based on the Safety Climate Assessment Tool (S-CAT) developed by the Center for Construction Research and Training (CPWR). This is the …

A Mixed-Methods Approach To Explore Student Perceived Needs For Peer Mentorship In A College Of Engineering, Darcie Christensen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

“Nobody makes it alone. Nobody has made it alone” (NOVA SHRM & Dulles SHRM, 2012, p. 5). Mentoring generally has positive outcomes, such as increasing output, staying in work or school, increasing confidence, and others (Campbell & Campbell, 2007; Crisp & Cruz, 2009; Eby et al., 2008; NASEM, 2019; Pfund et al., 2016). This dissertation study focused on student perceived needs for peer mentorship in engineering, which can fill in gaps of traditional mentorship by pairing mentors and mentees at similar levels, increasing comfort and emotional support to mentees (Allen et al., 2017; Haggard et al., 2011; Kram & Isabella, …

Venturi Meter Performance When Installed On The Branch Of A Tee Junction With Converging Run Flow, E. Elliot Naulu

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Venturi flow meters are often installed downstream of disturbances such as a tee junction, valve, or elbow. In such a case, a laboratory calibration may be needed to measure the Venturi meter’s performance under said limitations so that accurate metering is achieved. However, in some cases, laboratory calibration may not be possible.The purpose of this research was to investigate Computational Fluid Dynamics (CFD) ability to simulate a Venturi meter installed on the branch of a tee junction with converging run flow.

This study used CFD to compare against laboratory results to illustrate CFD’s capability as a calibration method. The results …