Engineering Commons^™

Demonstration Of A Third-Order Hierarchy Of Topological States In A Three-Dimensional Acoustic Metamaterial, Matthew Weiner, Xiang Ni, Mengyao Li, Andrea Alù, Alexander B. Khanikaev

Advanced Science Research Center

Classical wave systems have constituted an excellent platform for emulating complex quantum phenomena, such as demonstrating topological phenomena in photonics and acoustics. Recently, a new class of topological states localized in more than one dimension of a D-dimensional system, referred to as higher-order topological (HOT) states, has been reported, offering an even more versatile platform to confine and control classical radiation and mechanical motion. Here, we design and experimentally study a 3D topological acoustic metamaterial supporting third-order (0D) topological corner states along with second-order (1D) edge states and first-order (2D) surface states within the same topological bandgap, thus establishing …

University-Community Partnership For Water Technology Deployment And Co-Innovation: A Decade Of Engagement, Paul M. Cabacungan, Gregory L. Tangonan, Nerissa G. Cabacungan

Ateneo Innovation Center

The Ateneo de Manila University (Philippines), through its Ateneo Innovation Center (AIC), integrated existing simple technologies into one system – the Water-Electricity-Lighting System (WELS) – to respond to the need for potable water, lighting and communication. WELS is a portable clean water system with provision for lighting and cellular phone charging. It can be connected to a rainwater harvesting facility. Ten years of WELS deployments revealed its flexibility for customization in order to address varied water needs, especially for disaster response. Review of documentations done on past installation experiences highlights the value of engagement between university-based technology providers and community-recipients. …

Adaptive Filtration Of The Uav Movement Parameters Based On The Aoa-Measurement Sensor Networks, Igor Tovkach, Serhii Zhuk

International Journal of Aviation, Aeronautics, and Aerospace

Currently, the urgent task is to assess the small-sized maneuvering UAVs movement parameters. The location of an unknown UAV as a radio source can be determined using AoA measurements of the wireless sensor network. To describe the movement of a maneuvering UAV, a model is used in the form of a dynamic system with switching in discrete time. The values of switching variable determine type of UAV movement. To synthesize trajectory filtering algorithms, the Markov property of the extended process is used, which includes a vector of UAV movement parameters and a switching variable. The optimal trajectory filtering algorithm describes …

Numerical Investigation Of Darrieus Wind Turbine With Slotted Airfoil Blades, Ahmed Elbaz, Omar Sherif Mohamaed, Ahmed Abdelhamid Ibrahim, Ahmed Khaled Etman, Amr A. Abdelfattah

Mechanical Engineering

Low starting torque is considered as one of the major drawbacks of Darrieus type vertical axis wind turbine (VAWT). Design optimization to overcome this problem by modifying the airfoil geometry has received great attention by the wind energy community. Moreover, efforts have been directed towards augmenting the power coefficient of the turbine. In the present work, the effect of employing slotted airfoil as turbine blade on the performance and starting characteristics has been investigated. The slot parameters; slot location, angle of inclination, and dimensions, were optimized for NACA 0018 airfoil which is commonly used in Darrieus turbines. The flow over …

Wastewater Treatment Fatty Acids For Biodiesel Production, Zachary Christman

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

Wastewater scum is the thick oily substance that floats on top of the primary and secondary tanks within a wastewater treatment plant. Scum has a 30% to 60% lipid content making it an excellent resource for the biodiesel industry. Also the use of scum would reduce the cost of current management practices such as landfill disposal or incineration. In this article there is an overview of lipid byproducts currently being produced at wastewater treatment plants today. This is followed by a presentation showing a full length process for turning wastewater scum into biodiesel raw material.

Binder Saturation, Layer Thickness, Drying Time And Their Effects On Dimensional Tolerance And Density Of Cobalt Chrome - Tricalcium Phosphate Biocomposite, John Ruprecht

All Graduate Theses, Dissertations, and Other Capstone Projects

Traditional metals such as stainless steel, titanium and cobalt chrome are used in biomedical applications (implants, scaffolds, etc.) but suffer from issues such as osseointegration and compatibility with existing bone. One way to improve traditional biomaterials is to incorporate ceramics with these metals so that their mechanical properties can be similar to cortical bones. Tricalcium phosphate is such a ceramic with properties such that it can be used in the human body. This research explores the use of the Binder Jetting based additive manufacturing process to create a novel biocomposite made of cobalt chrome and tricalcium phosphate. Experiments were conducted …

Fault Detection And Classification Of A Single Phase Inverter Using Artificial Neural Networks, Ayomikun Samuel Orukotan

All Graduate Theses, Dissertations, and Other Capstone Projects

The detection of switching faults of power converters or the Circuit Under Test (CUT) is real-time important for safe and efficient usage. The CUT is a single-phase inverter. This thesis presents two unique methods that rely on backpropagation principles to solve classification problems with a two-layer network. These mathematical algorithms or proposed networks are able to diagnose single, double, triple, and multiple switching faults over different iterations representing range of frequencies. First, the fault detection and classification problems are formulated as neural network-based classification problems and the neural network design process is clearly described. Then, neural networks are trained over …

Selective Subtraction: An Extension Of Background Subtraction, Adeel Bhutta

Electronic Theses and Dissertations, 2020-2023

Background subtraction or scene modeling techniques model the background of the scene using the stationarity property and classify the scene into two classes of foreground and background. In doing so, most moving objects become foreground indiscriminately, except for perhaps some waving tree leaves, water ripples, or a water fountain, which are typically "learned" as part of the background using a large training set of video data. Traditional techniques exhibit a number of limitations including inability to model partial background or subtract partial foreground, inflexibility of the model being used, need for large training data and computational inefficiency. In this thesis, …

Understanding And Measuring Net Positive Business Strategies, Luke Ruffner Robinson

Graduate Student Theses, Dissertations, & Professional Papers

Despite their attempts to mitigate ecological impacts through sustainability initiatives, businesses are a major cause of the world's ecological problems. Some progressive businesses are attempting to move beyond “net zero” in terms of achieving neutral environmental impacts and instead are now pursuing a goal of net positive. Net positive refers to the idea that business activities could contribute value-added benefits to earth’s ecological systems, for example, by using technologies that sequester and store carbon. However, except for a handful of high-profile corporate case studies, little is known about how companies are developing their strategies to become net positive and …

In Situ Image Processing And Data Binning Strategy For Particle Engineering Applications, Toufic El Arnaout, Patrick J. Cullen

Articles

Crystallization control can be improved through real-time monitoring technologies. Here, a workflow is demonstrated on rapid batch cooling crystallization of L-glutamic acid. First, in situ images were generated using video microscopy sensors and analyzed, by employing a single, rapid macro code to extract particle data descriptors. A binning procedure (over time) was performed, where every data point represented the counts of particles within a specific size or shape range per 100 images. This binning method was found more informative in tracking of the populations compared to whole image averages or individual particle datapoints. This study provides a step-by-step guide towards …

Cost-Benefit Analysis Of Replacing Lpg Stoves With Induction Stoves In Rural Households Of Kavre District Nepal, Grishma Raj Dahal

Cal Poly Humboldt theses and projects

Nepal imports nearly 260,000 tons of Liquified Petroleum Gas (LPG) and other fossil fuels annually from India. This fuel dependency is one of the main reasons for Nepal’s trade deficit with India. The Government of Nepal has recently started promoting electric induction stoves for cooking as an alternative to LPG. Induction stoves are pollution free at the point of use, and they are meant to reduce Nepal's dependence on LPG.

This study includes a cost-benefit analysis for replacing LPG stoves with induction stoves for households in rural areas of Kavre District, Nepal. The study involved the use of data for …

Ethiopian Construction Project Management Maturity Model Determination And Correlational Prediction Of Project Success, Hailemeskel T. Hailemarkos

Walden Dissertations and Doctoral Studies

In Ethiopia, although the construction industry is booming, the practice of effective project delivery in time, cost, and quality remains a challenge. Construction project success comes through the application of knowledge-based, critically essential factors. The industry's effectiveness is dictated by the level of project management knowledge built in each company. The purpose of this quantitative, correlational study was to evaluate project management maturity level of construction industry and the predictability of project success from project management knowledge maturity of 193 project managers working in contractors, consultants, and clients. The study, which was informed by the project management body of knowledge …

Strategies Road Freight Transport Leaders Use To Increase Driver Retention, Johnny Mumphrey Jr.

Walden Dissertations and Doctoral Studies

The turnover of skilled over-the-road (OTR) truck drivers in the road freight transportation (RFT) industry results in significant yearly financial losses to organizations across the United States. Leaders in the industry continue to struggle to develop successful strategies for retaining these drivers. Grounded in the motivation hygiene theory, the purpose of this multiple case study was to explore strategies 5 transformational leaders from two RFT firms in North Texas used to improve OTR driver retention. Data collection included semi structured face-to-face interviews, a review of company webpages, and an assessment of company documents (e.g., employee handbooks, training manuals, and vision …

Exploring The Career Experiences Of Immigrant Nigerian Women Engineers, Ijeoma Lilian Ozoude

Walden Dissertations and Doctoral Studies

The contribution of immigrant Science, Technology, Engineering and Mathematics (STEM) workers in addressing the projected shortage of U.S. STEM workforce cannot be overemphasized. Despite efforts by U.S. policy makers to provide opportunities for a positive STEM experience and diversify the STEM field by increasing the number of underrepresented minorities and women via The Women and Minorities in STEM Booster Act, changes to the U.S. immigration policy towards Nigeria, including bans on immigrant visas and Diversity visas could impact recruitment of immigrant Nigerian workers in STEM. Using Kingdon’s multiple streams framework and Crenshaw’s intersectionality theory, this study explored the career experiences …

A Narrative Approach To Understanding Career Attrition For Women Engineers, Brian Merritt Scott

Walden Dissertations and Doctoral Studies

More women exit the engineering profession than enter, leaving a talent void that incurs lost business value from unrealized business revenues. Without new insights about how to address the continued attrition of women engineers, the profession is unlikely to sustain the human capital needed to achieve competitive advantages through innovation, increased productivity, and improved firm reputation. This qualitative narrative inquiry explored the career attrition phenomenon of six former women engineers in the Northern Tier States region of the United States who left engineering within the past 4 years and were either an engineer-in-training or professional engineer. The conceptual framework for …

Factors That Influence Throughput On Cloud-Hosted Mysql Server, Eric Brown

Walden Dissertations and Doctoral Studies

Many businesses are moving their infrastructure to the cloud and may not fully understand the factors that can increase costs. With so many factors available to improve throughput in a database, it can be difficult for a database administrator to know which factors can provide the best efficiency to maintain lower costs. Grounded in Six Sigma theoretical framework, the purpose of this quantitative, quasi-experimental study was to evaluate the relationship between the time of day, the number of concurrent users, InnoDB buffer pool size, InnoDB Input/Output capacity, and MySQL transaction throughput to a MySQL database running on a cloud, virtual, …

A Narrative Approach To Understanding Career Attrition For Women Engineers, Brian Merritt Scott

Walden Dissertations and Doctoral Studies

More women exit the engineering profession than enter, leaving a talent void that incurs lost business value from unrealized business revenues. Without new insights about how to address the continued attrition of women engineers, the profession is unlikely to sustain the human capital needed to achieve competitive advantages through innovation, increased productivity, and improved firm reputation. This qualitative narrative inquiry explored the career attrition phenomenon of six former women engineers in the Northern Tier States region of the United States who left engineering within the past 4 years and were either an engineer-in-training or professional engineer. The conceptual framework for …

Table Of Contents Jitim Vol 29 Issue 2, 2020

Journal of International Technology and Information Management

Table of contents

Proteomic Analysis Of Fetal Rat Neural Stem Cells After Treatment With Hericium Erinaceus, Bright Adam Test

University of the Pacific Theses and Dissertations

The fungus, Hericium erinaceus, has outstanding chemical properties, displaying health benefits in digestive, hepatic, and nervous tissues. Its ease of accessibility and use makes it one of the most common substances used for treatment in Eastern medicine. More and more recent research is confirming the incredible health benefits of this fungus, especially the impact that is seen on nervous tissue growth and recovery post-treatment. Such neurite outgrowth and myelin sheath regeneration could illustrate the beginning of the cure to lifelong neurodegenerative diseases such as Multiple Sclerosis. In this first-of-its-kind study, we cultured and differentiated fetal rat neural stem cells while …

Vehicle-Based Structural Health Monitoring Of Bridges, Zhenhua Shi

All ETDs from UAB

Structural health monitoring of bridges serves a critical role in maintaining a safe transportation network. Compared to the traditional resource-consuming direct approaches which usually require labor-intensive inspection and deployment of multiple sensors directly on the bridge, the indirect approach has been gained more and more attention due to its mobility and potential economy characteristics. The indirect approach utilizes the dynamic responses from the vehicle that interacts with the bridge so that the health status of the monitored bridges can be timely and effectively reflected via their structural dynamic characteristics such as frequencies, mode shapes, and damping properties. This research explores …

Epitranscriptomic Regulation Of Fibroblast Activation In Diseased Heart, Zainab Gbongbo Suleiman

All ETDs from UAB

Background: Transforming growth factor β (TGFβ) is a chemokine released during cardiac hypertrophy and remodeling. Evidence has shown that it plays a significant role in fibroblast differentiation/activation to myofibroblasts , which ultimately leads to adverse cardiac remodeling. It is previously suggested that m6A methylation plays important role in cardiac pathology in both ischemic and hypertrophic heart failure [1, 2], however, its role in fibroblast activation/differentiation is largely unknown. Therefore, in this study we investigated the relationship between m6A methylation and fibroblast activation using proinflammatory/profibrotic factor, TGFβ. Methods: Fibroblasts were isolated from neonatal rat heart and activated with TGFβ for 48 …

Assessing The Potential Of Public Transit Utility In Medium-Sized Cities Using Agent-Based Simulation, Taniya Sultana

All ETDs from UAB

At the beginning of the twentieth century, the United States was leading in the public transit sector, but following World War II, private car trips became more affordable and more popular, specially, in the last few decades. Transportation infrastructure investments that increased road capacity enabled the development of suburbs leading to urban sprawl and increase in automobile use at the expense of reduced public transit ridership. With the increase of dependency in automobiles and the continuing growth of private automobile ownership and use, various problems became major challenges in big cities of USA. These include traffic congestion, air pollution, road …

Uav Navigation, Tracking, And Interception Using Deep Reinforcement Learning, Ali Alhaj Darwish

All ETDs from UAB

We propose a self-supervised, model-free deep reinforcement learning architecture with cascade reward for unmanned aerial vehicle navigation and target interception in a 3D environment. The first contribution of the dissertation solves the problem of partial observability when non-linear function approximators are used for learning stochastic policies. The second contribution optimizes the problem of maximizing the total expected rewards. The third contribution trains the agent in a photo-realistic environment with a real physics engine. To achieve these goals, a deep Q-network that combines double and dueling architectures is adopted as a value function approximator, and the prioritized experience replays the sample …

Prediction Of The Optimal Catheter Placement Selection For Therapy Infusion To Treat Brain Tumors, Lisa Hope Antoine

All ETDs from UAB

ABSTRACT In 2020, the National Brain Tumor Society reported that physicians would diagnose more than 87,000 new cases of brain tumors. These cases will add to the approximately 700,000 individuals in the United States living with brain and central nervous system tumors. Almost 18,000 of these cases will prove fatal [1]. The blood-brain barrier (BBB) hinders the effective treatment of brain tumors. The task of this barrier is to protect the brain from composition instabilities in blood plasma and shield the brain from agents that may adversely impact brain functionality. However, by performing its tasks the barrier prevents potential effective …

Use Of Connected Vehicle Data In Support Of Signal Control Optimization, Gokmen Pacal

All ETDs from UAB

Traffic control signals are used to assign the right-of-way to traffic movements at intersections. By doing so, they facilitate the orderly movement of vehicles and pedestrians, improve the traffic-handling capacity of intersections and reduce the number of conflicts between movements, thus improving traffic safety. The most widely implemented method of traffic control is the fixed-time signals. Fixed-time traffic controllers use a simple electric mechanism that allow the signals to change at predefined time intervals; however, these simple mechanisms were not able to adjust to changes in traffic demand during the day. To address this issue, contemporary traffic signal controllers are …

Novel Methods For Image Analysis To Evaluate Relationships Between Biomarkers In Alzheimer's Disease, Fabio Raman

All ETDs from UAB

Neuroimaging biomarkers, including pathological amyloid and tau measured with positron emission tomography (PET) and neurodegeneration measured with magnetic res-onance (MR), are part of the research framework for Alzheimer’s disease (AD). Abnormal brain amyloid is currently the earliest established phenotypic marker of AD, and other imaging biomarkers such as tau-PET become abnormal later in the progression of AD pathophysiology. The ability to measure amyloid and predict both tau status and cogni-tion using a single amyloid-PET study through a method readily employed in both re-search and clinical settings would provide a valuable tool in assessing AD. The first goal of this dissertation …

Multi-Physics-Based Approach To Active Microwave Thermography, Seyed Ali Mirala

Doctoral Dissertations

“The goal of this work is to advance a novel nondestructive testing (NDT) method for controlled, rapid, and effective inspection of a structure through the integration of microwave NDT and thermography, referred to as Active Microwave Thermography (AMT). In AMT, the structure under test is exposed to microwave radiation and the thermal profile of the structure is monitored via a thermal camera in order to obtain desired information regarding the structure. This new technique is applicable across a wide range of NDT needs including detection of voids, delamination, water ingress, debonding, and cracks in numerous structures such as carbon fiber …

Predicting Complex System Behavior Using Hybrid Modeling And Computational Intelligence, Vinayaka Gude

Doctoral Dissertations

“Modeling and prediction of complex systems is a challenging problem due to the sub-system interactions and dependencies. This research examines combining various computational intelligence algorithms and modeling techniques to provide insights into these complex processes and allow for better decision making. This hybrid methodology provided additional capabilities to analyze and predict the overall system behavior where a single model cannot be used to understand the complex problem. The systems analyzed here are flooding events and fetal health care. The impact of floods on road infrastructure is investigated using graph theory, agent-based traffic simulation, and Long Short-Term Memory deep learning to …

Mesh Networking And Full-Duplex Communication For Wireless Networks, Arul Mathi Maran Chandran

Doctoral Dissertations

“Connectivity with large coverage area; and an increase in spectral efficiency of communications are highly desired features for any wireless network. The presented research work addresses these two feature improvements. First, the work analyzed mesh networks to enhance connectivity for wireless networks. The work analyzed both homogeneous and heterogeneous mesh networks. The work includes the development of an Android application to enable smartphones with multiple interfaces, such as Wi-Fi, Bluetooth, and cellular services, to become convergence devices. These convergence devices are then used to build a heterogeneous mesh network improving connectivity and coverage area. Second, the work explored full-duplex communications, …

An Integrated Wellbore Stability Study To Mitigate Expensive Wellbore Instability Problems While Drilling Into Zubair Shale/Sand Sequence, Southern Iraq, Ahmed Khudhair Abbas

Doctoral Dissertations

”The Zubair Formation is the most prolific reservoir in Iraq, which is comprised of sandstones interbedded with shale sequences. Due to the weak nature of the shale sequence, the instability of a wellbore is one of the most critical challenges that continuously appears during drilling across this formation. Historically, over 90% of wellbore problems in the Zubair Formation were due to wellbore instability. Problems associated with wellbore instability, such as tight hole, shale caving, stuck logging tools along with subsequent fishing, stuck pipe, and sidetracking result in increasing the non-productive time. This non-productive time has cost an enormous amount of …