Engineering Commons^™

Training-Informed Air Traffic Control Workforce Scheduling, Eli Winett

Theses and Dissertations

The Radar Control Facility (RCF) at Eglin Air Force Base creates monthly workforce schedules. Adherence to regulations must be verified manually and no evaluation criteria exist to compare schedules. A mixed-integer program model for air traffic controllers allocates workers across 19 positions for a user-defined number of weeks of 24-hour operations. Across eight consecutive months, this model produced schedules to nearly eliminate all shifts with critical shortages from the reference schedules. Without civilian overtime work, gains in positional coverage require a 35% increase in overtime work for military workers and 35% reduction in monthly training instances. We recommend users adopt …

Stress-Dependent Mohr–Coulomb Shear Strength Parameters For Intact Rock, Hao Li, Leo Pel, Zhenjiang You, David Smeulders

Research outputs 2022 to 2026

Rock strength is imperative for the design and stability analysis of engineering structures. The Mohr–Coulomb (M-C) criterion holds significant prominence in geotechnical engineering. However, the M-C criterion fails to accurately capture the nonlinear strength response and neglects the critical state of rocks, potentially leading to inaccuracies in the design phase of deep engineering projects. This study introduces an innovative stress-dependent friction angle and cohesion (SFC) for the M-C criterion to capture the nonlinear strength responses of intact rocks, spanning from non-critical to critical states (brittle to ductile regions). A novel method for determining these stress-dependent parameters at each corresponding σ3 …

Mechanical Properties And Microstructural Investigation Of Aa2024-T6 Reinforced With Al2o3 And Sic Metal Matrix Composites, Hassan Raza Channar, Barkat Ullah, Muhammad Shoaib Naseem, Javed Akhter, Arshad Mehmood, Muhammad Aamir

Research outputs 2022 to 2026

Aluminium metal matrix composites (AMMCs) using alumina (Al2O3) and silicon carbide (SiC) as reinforcement elements are gaining significant interest in various applications because of their excellent properties. In this study, Al2O3/SiC with compositions (0.5 wt.%, 1.5 wt.%, and 2.5 wt.% for each) were used as reinforcement elements in an aluminium alloy (AA2024-T6). The samples prepared were AA2024-T6 + (0.5Al2O3/0.5SiC), AA2024-T6 + (1.5Al2O3/1.5SiC), and AA2024-T6 + (2.5Al2O3/2.5SiC) using a stir-casting technique. The experimental study included density calculation mechanical properties, such as tensile strength, compressive strength and hardness. The study also included a microstructure examination of the fracture surface of the tensile …

A Techno-Economic Perspective On Efficient Hybrid Renewable Energy Solutions In Douala, Cameroon’S Grid-Connected Systems, Reagan Jean Jacques Molu, Serge Raoul Dzonde Naoussi, Mohit Bajaj, Patrice Wira, Wulfran Fendzi Mbasso, Barun K. Das, Milkias Berhanu Tuka, Arvind R. Singh

Research outputs 2022 to 2026

Cameroon is currently grappling with a significant energy crisis, which is adversely affecting its economy due to cost, reliability, and availability constraints within the power infrastructure. While electrochemical storage presents a potential remedy, its implementation faces hurdles like high costs and technical limitations. Conversely, generator-based systems, although a viable alternative, bring their own set of issues such as noise pollution and demanding maintenance requirements. This paper meticulously assesses a novel hybrid energy system specifically engineered to meet the diverse energy needs of Douala, Cameroon. By employing advanced simulation techniques, especially the Hybrid Optimization Model for Electric Renewable (HOMER) Pro program, …

Identifying Payable Cluster Distributions For Improved Reservoir Characterization: A Robust Unsupervised Ml Strategy For Rock Typing Of Depositional Facies In Heterogeneous Rocks, Umar Ashraf, Aqsa Anees, Hucai Zhang, Muhammad Ali, Hung Vo Thanh, Yujie Yuan

Research outputs 2022 to 2026

The oil and gas industry relies on accurately predicting profitable clusters in subsurface formations for geophysical reservoir analysis. It is challenging to predict payable clusters in complicated geological settings like the Lower Indus Basin, Pakistan. In complex, high-dimensional heterogeneous geological settings, traditional statistical methods seldom provide correct results. Therefore, this paper introduces a robust unsupervised AI strategy designed to identify and classify profitable zones using self-organizing maps (SOM) and K-means clustering techniques. Results of SOM and K-means clustering provided the reservoir potentials of six depositional facies types (MBSD, DCSD, MBSMD, SSiCL, SMDFM, MBSh) based on cluster distributions. The depositional facies …

Synthesis Of Geopolymer Mortar From Biomass Ashes And Forecasting Its Compressive Strength Behaviour, P. J. Ardhira, Sanjay Kumar Shukla, Dhanya Sathyan

Research outputs 2022 to 2026

The global warming dilemma raised an exigency toward sustainability in the construction industry and compelled scientists to hunt for alternative binders in construction materials. The, geopolymerization as a spectacular technology has arisen as a looming solution to this dilemma. This work assesses the features of geopolymer mortar developed with both industrial and agricultural wastes at ambient temperature curing. The geopolymer mix proportion was evolved in this study using main precursor material as fly ash, ground granulated blast furnace slag (GGBFS), sugarcane bagasse ash (SCBA) or rice husk ash (RHA). Workability and mechanical properties, including compressive strength, flexural strength, and split …

Stress-Dependent Instantaneous Cohesion And Friction Angle For The Mohr–Coulomb Criterion, Hao Li, Leo Pel, Zhenjiang You, David Smeulders

Research outputs 2022 to 2026

The strength criterion of rock is essential for stability control and safety design of geotechnical engineering constructions. Due to its widespread adoption, the Mohr–Coulomb (M-C) criterion is prominent among strength criteria. However, the M-C criterion is constrained by three significant limitations: it fails to capture the nonlinear strength response, overlooks the critical state, and disregards σ2. This study introduces a novel Stress-dependent Instantaneous Friction angle and Cohesion (SIFC) model for the M-C criterion to represent the convex strength envelope of intact rock, covering the spectrum from non-critical to critical states. In pursuit of this objective, an innovative approach for calculating …

Portable Multiplexed Ion-Selective Sensor For Long-Term And Continuous Irrigation Water Quality Monitoring, Mojtaba Abdollahzadeh, Yujie Zhu, Bita Bayatsarmadi, Mikko Vepsäläinen, Amir Razmjou, Krishnan Murugappan, Theo Rodopoulos, Mohsen Asadnia

Research outputs 2022 to 2026

In agricultural contexts, the demand for continuous and precise measurement of multiple ions is crucial. While arrays of solid-contact ion-selective electrodes (SCEs) have been developed previously, there has been limited emphasis on their continuous and long-term monitoring of ions. Addressing this gap, our work introduces an innovative sensor array utilizing Ni-HAB MOF as an ion-to-electron transducer, enabling real-time detection of nitrate, potassium, and pH levels. The sensors exhibit exceptional stability, eliminating the need for frequent recalibration. For instance, the K+-selective sensor displays an unprecedentedly low potential drift of 0.05 µV/h, surpassing existing solid-contact sensors by two orders of magnitude. Similarly, …

Surface Interaction Changes In Minerals For Underground Hydrogen Storage: Effects Of Co2 Cushion Gas, Hamid Esfandyari, Alireza Safari, Ali Hashemi, Aliakbar Hassanpouryouzband, Manouchehr Haghighi, Alireza Keshavarz, Abbas Zeinijahromi

Research outputs 2022 to 2026

Hydrogen (H2) offers a promising solution for the energy transition but storing it on a large scale at the surface poses significant technical and environmental challenges. Underground formations provide a practical alternative for large-scale H2 storage, yet understanding H2 behavior under various subsurface conditions is crucial for optimizing storage capacity and efficiency, which are influenced by rock properties such as wettability. This study addresses the gap in literature regarding the wettability of different minerals when CO2 was injected with H2 as a cushion gas. We examined the wettability of various mineral rocks in realistic subsurface circumstances. A series of wettability …

White Hall Green Roof Proposal, Hope Dwyer

Biological and Agricultural Engineering Undergraduate Honors Theses

This project will propose designs for a GR system while determining the potential cost, the feasibility of the system implementation, as well as potential psychological and educational benefits of a GR system. These factors will be examined and evaluated with regard to two different proposed GR designs: extensive and intensive.

Compact Solar-Powered Plasma Water Generator: Enhanced Germination Of Aged Seed With The Corona Dielectric Barrier Discharger, Yiting Xiao, Yang Tian, Haizheng Xiong, Ainong Shi, Jun Zhu

Biological and Agricultural Engineering Faculty Publications and Presentations

Seed aging adversely affects agricultural productivity by reducing germination rates and seedling vigor, leading to significant costs for seed banks and companies due to the need for frequent seed renewals. This study demonstrated the use of plasma-activated water (PAW), generated by a solar-powered corona dielectric barrier discharger, to enhance germination rates of spinach seeds that had been stored at 4 °C for 23 years. Treating seeds with PAW at 17 kV for 15 min improved germination (by 135%) and seedling growth compared to untreated seeds. Through detailed analysis, beneficial PAW properties for seed development were identified, and a molecular mechanism …

Corrosion Behavior Of Laser Powder Bed Fusion Additive Manufacturing Produced Tini Alloy By Micro-Arc Oxidation, Xin Zhao, Yicheng Liu, Chenfan Jia, Hao Chang, Wei Zhang, Yun Bai, Shujun Li, Lai-Chang Zhang, Wei Yuan

Research outputs 2022 to 2026

To improve the corrosion resistance of TiNi alloy fabricated by laser powder bed fusion (LPBF), a porous oxidation layer was synthesized by micro-arc oxidation in a sodium aluminate and sodium silicate electrolyte. The influences of the applied voltage and the processing time on the morphology of oxidation layer were investigated, and the corrosion behavior of the oxidation layer in artificial saliva was evaluated and compared with that of the as-fabricated LPBF alloy. The results indicate that, as increasing the applied voltage and the processing time, the oxidation layer becomes uniform and integrated. The optimum parameters are with an applied voltage …

A Secure Cross-Domain Authentication Scheme Based On Threshold Signature For Mec, Lei Chen, Chong Guo, Bei Gong, Muhammad Waqas, Lihua Deng, Haowen Qin

Research outputs 2022 to 2026

The widespread adoption of fifth-generation mobile networks has spurred the rapid advancement of mobile edge computing (MEC). By decentralizing computing and storage resources to the network edge, MEC significantly enhances real-time data access services and enables efficient processing of large-scale dynamic data on resource-limited devices. However, MEC faces considerable security challenges, particularly in cross-domain service environments, where every device poses a potential security threat. To address this issue, this paper proposes a secure cross-domain authentication scheme based on a threshold signature tailored to MEC’s multi-subdomain nature. The proposed scheme employs a (t,n) threshold mechanism to bolster system resilience and security, …

Hydraulic Boundary Conditions Determine Biofilm Growth Patterns And Permeability In Groundwater, Jason Tyler Mick

Boise State University Theses and Dissertations

Biofilms are naturally occurring consortia of bacteria that colonize porous media such as streambed sediments, soils, and aquifers. Biofilm growth leads to clogging (i.e., bioclogging), which reduces the porosity and permeability of the porous medium and directly influences how nutrients and contaminants are transported and transformed in groundwater. To improve our understanding of how bioclogging regulates nutrient and contaminant fluxes, we must better characterize how flow conditions influence the spatial and temporal progression of biofilm growth within natural porous media geometries, as well as understand how this progression alters fluid flow.

In this study, I conducted microfluidic experiments to test …

Accelerating Microbial-Induced Calcite Precipitation Treatment Protocols Using Calcium-Based Stabilizers Targeting Pavement Construction, Grant Goertzen

Boise State University Theses and Dissertations

The research, development, and implementation of sustainable and resilient infrastructure is a critical mission for all aspects of modern Civil Engineering. The engineering and construction sector accounts for 37% of all global greenhouse gas emissions, comprising the largest proportion of any industry (Kafu-Quvane et al. 2024). Typically comprising 100% of base and subbase layers, 90% of asphalt pavement, and 80% of concrete pavement, it takes approximately 38,000 tons of aggregate to construct a single-lane mile of interstate highway (Feuling 2024). This presents significant environmental challenges due to the negative impacts of quarrying and aggregate transportation such as habitat destruction, biodiversity …

Stability Of Nuclear Thermocouples, Scott Riley

Boise State University Theses and Dissertations

The mission of the Department of Energy, Office of Nuclear Energy (DOE-NE) is to advance nuclear power as a resource capable of meeting the nation’s energy, environmental and national security needs by resolving technical, cost, safety, proliferation resistance, and security barriers through research and development. In the pursuit of safer and more economic energy production from existing nuclear reactors and future generation IV reactors, new cladding, fuel, and structural materials are being developed. However, data on the performance of these materials in accident scenarios and relevant generation IV reactor conditions is limited. Currently, thermocouples are the most commonly used temperature …

Analysis Of Learning Mechanisms In Spiking Neural Networks With R(T) Elements And Memristive Synapses, Farhana Afrin

Boise State University Theses and Dissertations

As Moore's law ends, the conventional von Neumann computer architecture with binary-coded data representation has reached its bottleneck because of having separate computing and memory modules. In this architecture, continuous power is required due to sequential processing, making it challenging to improve efficiency further. The human brain can be regarded as the most energy-efficient computer architecture. In the brain, data is represented as small voltage pulses as spikes. That is why the neural units are called spiking neural networks (SNN). In SNNs, energy is required only when there is a spike, making it more energy efficient than the von-Neumann computer …

Multi-Scale Modeling Of Dna-Templated Aggregates For Excitonic Applications, German Barcenas Moncada

Boise State University Theses and Dissertations

Quantum entanglement occupies a central role in the application of quantum mechanics towards emerging technologies of quantum information systems. Meanwhile, quantum entanglement is believed to be observed at room temperature in photosynthetic complexes in plants and algae through the energy transfer of dye molecules. The goal of this project is to engineer dye properties and their arrangement when dyes and aggregates are covalently attached to DNA so that the emergent property of exciton delocalization is as coherent, predictable, detectable and controllable. The creation of such a platform would enable the continued study of near room-temperature quantum entanglement and the more …

Assembly And Characterization Of 10 Cm × 10 Cm Cold Atmospheric Pressure Plasma Device, Sumona S. Islam

Boise State University Theses and Dissertations

The primary purpose of this thesis is to assemble, demonstrate, and characterize a Cold Atmospheric Pressure dielectric barrier discharge plasma array of large active plasma discharge region (10 cm × 10 cm). The array is fabricated using the Low Temperature Co-Fired Ceramic (LTCC) dielectric material system and silver paste in printing electrodes. It is important to find the optimal operating parameters of the device to achieve uniform emission and to achieve the best response out of the device, which is the main focus of this thesis. The device is assembled from 43 linear discharge elements. Several I-V sweep measurements, capacitance …

Engineered Microalgae Cultivations Systems: Conversion Of Wastewater Nutrients Into Biofuels And Bioplastics, Jacob Watkins

All Graduate Theses and Dissertations, Fall 2023 to Present

Dissolved Nitrogen and Phosphorus in wastewater can contribute to harmful algae blooms if released into the environment. One technology that can be used to recover dissolved nutrients from wastewater is the Rotating Algae Biofilm Reactor (RABR), which supports microalgae growth in an easily-harvested biofilm and produces nitrogenand phosphorus-rich biomass that can be used to produce slow-release fertilizers, biofuels, and compostable bioplastics. This thesis (1) examines the effects of several environmental factors on the biomass production rate and nutrient removal efficiency of RABRs treating municipal wastewater, (2) quantifies the composition and biofuel yields of microalgae biomass cultivated using a RABR at …

Finite-Time Control Strategies For Rendezvous And Proximity Operations, John Tamotsu Akagi

All Graduate Theses and Dissertations, Fall 2023 to Present

One common metric to use when designing a controller is the time that the system will take to reach the desired state. Unfortunately, many approaches to developing controllers only guarantee that the system will approach, but not exactly reach, the desired state. This can become a limitation in time-sensitive situations where rapid and complete convergence is necessary. One group of control methods, known as finite-time control, does guarantee both faster convergence and that the desired state will be reached, but often fails to define exactly what time that will occur, how much control will be used to get there, and …

Analysis Of An Outdoor Pilot-Scale Rotating Algae Biofilm Reactor For Power Optimization, Ash-Enhanced Productivity, And Nutrient Uptake, Peter F. Jeppesen

All Graduate Theses and Dissertations, Fall 2023 to Present

Outdoor testing of a rotating algae biofilm reactor (RABR) was performed to see how well it could remove nutrients from water and produce algae. By adjusting the operation settings, we found the lowest power needed to remove nitrogen and phosphorus. The lowest power values needed were 1.36 kWh per kilogram of nitrogen and 20.1 kWh per kilogram of phosphorus. The algae production rate reached a maximum of 7.09 grams per square meter per day. Detailed analysis showed that the reactor worked like a continuous flow system, and the performance was influenced by factors including light and temperature. The results also …

Examining The Impacts Of Demographics, Individual Experiences, And Perceptions On Range Anxiety And Electric Vehicle Road Trips, Joshua Ward

All Graduate Theses and Dissertations, Fall 2023 to Present

Range anxiety is perhaps the most widely cited barrier to electric vehicle (EV) adoption and use. Range anxiety is generally defined as a general fear that an EV has insufficient battery range or that there is insufficient charging infrastructure to travel from one place to another. Although this barrier is widely cited, there is little research that investigates how EV drivers experience range anxiety and how it might vary based on personal characteristics, perceptions, and experiences. Data on long-distance EV trips is also scarce in the United States and mainly limited to personal stories of an EV road trip.

This …

Techno-Economic Factors Impacting The Intrinsic Value Of Behind-The-Meter Distributed Storage, Ingrid Hopley, Mehrdad Ghahramani, Asma Aziz

Research outputs 2022 to 2026

With the increasing adoption of renewable energy, there is a growing need for efficient storage solutions. Battery storage is becoming an essential tool for maintaining grid reliability and handling the variable nature of renewable energy sources. This research focuses on behind-the-meter, grid-connected household systems in Western Australia, adopting a consumer perspective to evaluate the financial viability of residential batteries. Using the HOMER Grid for techno-economic modeling, eight factors influencing financial viability were analyzed, with results validated through two external case studies. The findings suggest that photovoltaic (PV) systems paired with batteries can be cost-effective at current prices, depending on load …

Understanding Failure Mechanisms For Two Colorectal Anastomosis Techniques, Youssef Sherif Sadek Fahmy

UNLV Theses, Dissertations, Professional Papers, and Capstones

Colorectal Surgery continues to be one of the most common gastrointestinal surgeries performed in the US. A common complication known as Anastomotic Leakage (AL) that threatens up to 30% of patients with this surgery. Many cases of AL can decrease the quality of life for patients or extensively extend hospital stays, and in many cases, lead to death. Researchers have studied this complication in clinical trials, yet few studied the mechanics of stapled anastomosis in controlled environments. The purpose of this research was to understand the mechanical interaction between the staples and the tissue, and to eventually apply it in …

Development Of Uranium Fluoride Microstructures, Harry Jang

UNLV Theses, Dissertations, Professional Papers, and Capstones

Uranium microstructured materials with controlled size and shape have found applications in several branches of the nuclear industry including as targets for medical isotopes production, fuels for nuclear reactors, standards for analytical measurements, and energy sources for space exploration. Morphological studies of actinide materials are also highly relevant to nuclear forensics-related work. Other potential applications include information storage, catalysis, sensors, and luminescent devices. Most studies on uranium microstructured materials have focused on binary oxides, nitrides, carbides, and fluorides, with the spherical shape being the dominant morphology. Prior to the work reported in this dissertation, aside from UF4 microspheres (ms) and …

Investigation Ionic Polymer Metal Composite Capacitors Through Fabrication, Experimentation, And Modeling, Liya S. Napollion

UNLV Theses, Dissertations, Professional Papers, and Capstones

The increasing demand for greater energy storage capacity alongside the need to minimize the size of various devices, such as hybrid electric vehicles, medical devices, and pulsed power systems—has highlighted the necessity for advanced polymer film capacitors with high energy density. While traditional batteries and electronic devices have generally sufficed for many applications, their inherent size limitations hinder their ability to deliver the high levels of peak power required for certain demanding applications. This shortfall highlights the critical ongoing challenge within the energy storage sector to improve technology and more effectively meet these growing power requirements. Flexible Ionic Polymer Metal …

Control Of X-Delta Arm And Self-Leveling Robot Systems For Uav Applications, Prathibha Sobha

UNLV Theses, Dissertations, Professional Papers, and Capstones

The water droplet penetration test (WDPT) is an environmental assessment method for analyzing soil properties by measuring the penetration of water droplets into soil. This test provides insights into soil moisture retention and resilience, especially valuable in fire-prone or arid regions where soil recovery and erosion control are essential. Although this project does not conduct an actual WDPT, it investigates two key robotic systems designed to support such applications: an X-delta robot arm, which simulates precise droplet delivery patterns, and a self-leveling platform that ensures stability on uneven terrain, where the X-delta robot is mounted. Together, these systems examine the …

Fast Neutron & Gamma-Ray Scintillation And Broadband Photoluminescence From Gallium Nitride & Gallium Oxide: Developing Radiation-Hard Diagnostic Platforms, Daniel Jesus Valdes

UNLV Theses, Dissertations, Professional Papers, and Capstones

Integrated scintillation and electronics processing materials are of critical importance in environments exposed to high levels of radiation, such as nuclear fusion diagnostics and space missions. This dissertation focuses on the radiation detection capabilities of gallium oxide (Ga2O3) and gallium nitride (GaN), exploring their responses to fast neutrons and gamma rays. Using high-energy neutron beam facilities at Los Alamos Neutron Science Center (LANSCE) Flight Path 4FP60R, we exposed both Ga2O3 and GaN crystals to neutron irradiation spanning an energy spectrum ranging from 1 to 400 MeV. A Pi-Max 4 fast-gated Intensified CCD (ICCD) camera captured the transient scintillation responses for …

Impact Of Weather Systems On Uav Parameters Using Computational Fluid Dynamics, Saif Aljuhaishi, Yaseen K. Al-Timimi, Basim I. Wahab

Karbala International Journal of Modern Science

Since drones cannot fly in any kind of weather, they are not safe for time-sensitive activities. The study examines how the passage of weather systems in Iraq leads to the ban on drone flights, and how these weather conditions impact the aerodynamic forces of the drone. Hourly climate data for the study area were obtained from ECMWF ERA5 and CAMS in NetCDF format for four climate stations (Erbil, Baghdad, Rutbah, and Basrah). A ScanEagle drone was chosen for this study. The Python programming language was used to perform mathematical operations to calculate the ban on drone flights. ArcGIS 10.8 was …