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Full-Text Articles in Engineering

Intrinsic Manipulation Of Microstructure And Strength Of Ice-Templated Lithium Titanate, Rohan Parai Oct 2024

Intrinsic Manipulation Of Microstructure And Strength Of Ice-Templated Lithium Titanate, Rohan Parai

Mechanical & Aerospace Engineering Theses & Dissertations

This dissertation focuses on developing a fabrication landscape first time ever for directionally porous lithium titanate (LTO) materials using ice-templating technique. Ice-templating, a promising fabrication technique for porous ceramics, enables the formation of sintered structures with anisotropic pores that are aligned to improve mechanical stability of materials.

The work presented in this dissertation addresses advancements in tuning the porosity, strength, and microstructural characteristics of ice-templated LTO materials through adjustments of intrinsic variables, including sucrose as a water-soluble additive, variations in freezing front velocity, solute concentration, and solid loading. First, this study demonstrated that adding sucrose in LTO suspensions increased the …


Suppression Of Dynamic Aeroelastic Response Of A Semispan Wing Using Traditional And Distributed Sensing, James Ramey Oct 2024

Suppression Of Dynamic Aeroelastic Response Of A Semispan Wing Using Traditional And Distributed Sensing, James Ramey

Mechanical & Aerospace Engineering Theses & Dissertations

Characterization and management of aeroelastic effects are a vital part of aircraft design. Mitigation of these effects often includes control systems to suppress the vibrations. Control systems are constantly being developed and improved, with one such avenue of development being new sensing systems that can increase the information fed into the controller. Fiber Optic Strain Sensing (FOSS) technology is one such system that utilizes Fiber Bragg Gratings (FBGs) on a fiber optic cable to sense the strain on structural elements. This system has promise as a high-density feedback device, and the maturation of the technology has allowed assessment of its …


An Agent-Based Approach For Designing A Sustainable Supplier Selection In Stochastic Environment: A Simulation Study, Sheida Etemadidavan Oct 2024

An Agent-Based Approach For Designing A Sustainable Supplier Selection In Stochastic Environment: A Simulation Study, Sheida Etemadidavan

Engineering Management & Systems Engineering Theses & Dissertations

In the 21st century, businesses are constantly striving for competitive advancement and increasing their economic performance in the rapidly changing market. Collaboration with other businesses and partnerships with them are becoming more common. As such, businesses are starting to invest in finding the right partners to stay competitive in an ever-changing business landscape. Suppliers play a crucial role in businesses' decision-making as they provide the materials, goods, and services necessary for a company to operate and succeed. Therefore, their selection, management, and relationship must be carefully considered to ensure optimal performance and profitability. A sustainable framework in a business's relationship …


Roles Of The His-Purkinje System In Long Qt Syndrome Mediated Arrhythmias, Anthony Owusu-Mensah Oct 2024

Roles Of The His-Purkinje System In Long Qt Syndrome Mediated Arrhythmias, Anthony Owusu-Mensah

Biomedical Engineering Theses & Dissertations

Long QT syndrome (LQTS) is a genetic or drug-induced electrophysiological disorder in the heart that prolongs the QT interval on the electrocardiogram. LQTS is present in considerable proportions (1:3000 to 1:5000) of the general population. LQTS has a high incidence of malignant ventricular arrhythmias during physical and emotional stress and is a significant cause of sudden death in younger subjects. This poses a substantial medical burden on the healthcare system in terms of morbidity, mortality, and finances. Despite extensive genetic research into LQTS, the mechanisms underlying spontaneous initiation and maintenance of arrhythmias are not fully understood. Beta-blockers are the standard …


Concrete Design: Underwater Concrete Forms In A Saltwater Environment, Noah Z. Lau Oct 2024

Concrete Design: Underwater Concrete Forms In A Saltwater Environment, Noah Z. Lau

Construction Management

This following project investigated the effects of salt on the concrete curing process. Concrete possesses numerous strengths, making it extremely versatile. This makes it one of the most utilized construction materials. New improved methods are constantly being developed for concrete’s application as a construction material. While concrete is a flexible material with many strengths, it is not without its flaws. Concrete, while strong in compression is weak in tension. It has long cure times and doesn’t generally handle moisture well. This paper evaluates concrete’s change in strength from letting concrete cure in a salt-based underwater environment. To determine the full …


California Polytechnic Architecture Graveyard Safety And Locational Signage Project, Luke C. Vanderkooij Oct 2024

California Polytechnic Architecture Graveyard Safety And Locational Signage Project, Luke C. Vanderkooij

Construction Management

Hiking along Poly Canyon Road, towards Cal Poly’s Architecture Graveyard, limited information can be located on the actual trail, with current signage only describing prohibited activities. This project aimed to provide needed safety and locational signage for pedestrians, bikers, and vehicles, clearly outlining maps, safety tips, and emergency contacts. These criteria were led by the desire to proactively limit the risk of traveling along Poly Canyon Road and provide reactive assistance for those in potential danger. These added informational improvements were decided to be included in a bulletin style enclosure with a roof and metal plaque anchored into a reinforced …


Design Of An Above Pavement Wireless Sensor Node (Apwsn) For Real-Time Roadway Monitoring Using Piezoelectric Energy-Harvesting, Jochy Jonathan Perez Sep 2024

Design Of An Above Pavement Wireless Sensor Node (Apwsn) For Real-Time Roadway Monitoring Using Piezoelectric Energy-Harvesting, Jochy Jonathan Perez

Theses and Dissertations

The evolution of Smart Highway and Internet of Things (IoT) technologies offers new opportunities to improve the safety and efficiency of vehicular traffic on roads. This research effort describes the development of a wireless pavement sensor that provides a novel method to detect key pavement parameters while incorporating low-power energy harvesting that leverages the kinetic energy generated by vehicular traffic. The Above Pavement Wireless Sensor Node (APWSN) is the embodiment of the approach. APWSN can facilitate the strategic deployment of sensors on a wide variety of roads to enable real-time data collection to support decision-making processes for road infrastructure maintenance …


A Novel Approach To Evaluate Seatbelt Non-Compliance Of Drivers In New Jersey, Md Arifuzzaman Nayeem Sep 2024

A Novel Approach To Evaluate Seatbelt Non-Compliance Of Drivers In New Jersey, Md Arifuzzaman Nayeem

Theses and Dissertations

This study intends to investigate the non-compliant behavior of drivers with seatbelt use in New Jersey. By examining various factors such as temporal and roadway characteristics, this study seeks to identify the underlying causes of this seatbelt non-compliance behavior. To overcome the limitations of traditional methods like cross-sectional data collection, a novel approach known as moving vehicle method was employed. To gain further insights, hypothesis tests were performed across the entire dataset to pinpoint significant temporal, roadway, and geometric factors contributing to non-compliant behaviors. In the subsequent step, the association of other risky behaviors like speeding and distracted driving with …


Development Of Electrically Conductive Asphalt Pavements For Deicing Applications In Cold Regions, Ashith Marath Padinhare Purakkal Sep 2024

Development Of Electrically Conductive Asphalt Pavements For Deicing Applications In Cold Regions, Ashith Marath Padinhare Purakkal

Theses and Dissertations

Winter conditions often lead to significant traffic delays and safety risks due to ice or snow accumulation on pavement surfaces. This study evaluates the potential of electrically conductive asphalt (ECA) pavements to prevent such accumulations by melting ice and snow under real-world conditions. The study involved preparing ECA mixtures using graphite and carbon fibers, three carbon fiber lengths (3 mm, 6 mm, and 24 mm), and aggregates with two nominal maximum aggregate sizes (NMAS) (4.75 mm and 9.5 mm). Electrical resistivity, rutting susceptibility and cracking resistance of compacted ECA mixtures were evaluated. Results indicated that ECA mixtures with 15% graphite …


Design, Characterization, And Simulation Of A 2d Dual-Rail Quantum Processor, Diego Barrutia Sep 2024

Design, Characterization, And Simulation Of A 2d Dual-Rail Quantum Processor, Diego Barrutia

Dartmouth College Master’s Theses

Bosonic systems, such as three-dimensional (3D) λ/4 coaxial cavities and two-dimensional (2D) λ/2 coplanar waveguide (CPW) resonators, are quantum harmonic oscillators that encode information in phase space, offering a hardware-efficient route toward quantum error correction and simulation in superconducting circuits. In this thesis, we present the design, characterization, and simulation of a dual-rail processor constructed with a 2D λ/2 coplanar waveguide resonators, demonstrating a percent error between experimental and analytical results within a range of 3.31% - 13.16%. The analytical results exhibit high precision but lower accuracy relative to experimental measurements. By integrating both closed-source and open-source software tools, we …


Distracted Driving: Identification, Contributing Factors, And Safety Countermeasures, Ahmed Sajid Hasan Sep 2024

Distracted Driving: Identification, Contributing Factors, And Safety Countermeasures, Ahmed Sajid Hasan

Theses and Dissertations

Distracted driving is a hazardous behavior responsible for 25% of all fatal traffic crashes in New Jersey. While traditional methods such as surveys, videos, and simulations have been used to identify and evaluate distracted driving events, these approaches primarily provide cross-sectional data that fails to capture the true rate of distraction on the road. This study addresses this limitation by collecting longitudinal data on distracted driving events across selected corridors in New Jersey. A data collection team continuously drove through these corridors, manually counting and video recording driver distraction events. The collected data was then analyzed to assess the significance …


3d Bioactive Thiol-Norbornene Hydrogels For Guiding Stem Cell Mechanosensing And Differentiation, Arielle Gsell Sep 2024

3d Bioactive Thiol-Norbornene Hydrogels For Guiding Stem Cell Mechanosensing And Differentiation, Arielle Gsell

U-RISE Undergraduate Theses

Hydrogels are soft, highly hydrated polymeric networks commonly used as biomaterial scaffolds in tissue engineering. To mimic the extracellular matrix of tissues, hydrogels can be chemically modified to incorporate either bioactive molecules such as peptides, or physically modified with crosslinkers to alter hydrogel stiffness and degradation. Hydrogels with defined characteristics can be synthesized using chemical reaction schemes such as photo-click chemistry, which offers spatial and temporal control over biochemical and physical properties. The goal of this thesis is to leverage thiol-norbornene click chemistry, a subtype of photo-click chemistry, to develop 3D hydrogels with biochemical and biophysical cues that guide mesenchymal …


Development Of A Haptic System For Robot-Assisted Femur Fracture Surgery, Fayez H. Alruwaili Sep 2024

Development Of A Haptic System For Robot-Assisted Femur Fracture Surgery, Fayez H. Alruwaili

Theses and Dissertations

Robot-assisted surgery has emerged within the field of surgical technology, driven by the need for greater accuracy and speed in the ongoing evolution of healthcare. This advancement has influenced numerous areas requiring enhancements to achieve optimal surgical results. However, surgical robotics tends to lack the surgeon’s connection to the operation, creating a gap in the intuitive skill set required for successful operations. The gap is seen through the lack of sense of touch, which may result in tissue damage and additional injury when the robot interacts with the patient. Furthermore, challenges faced during femur fracture surgery have positioned robot-assisted surgery …


Injectable Hydrogels That Can Measure Radiation At Body Temperature, Daniel Joseph Ball Sep 2024

Injectable Hydrogels That Can Measure Radiation At Body Temperature, Daniel Joseph Ball

Theses and Dissertations

Hydrogel-based radiation dosimeters are used to calibrate and validate radiation delivered by linear accelerators used in radiotherapy. Specifically, Fricke hydrogel-based dosimeters containing ferrous ion complexes oxidize upon exposure to radiation, leading to a change in optical density that can be measured via a color change in a photometric reagent. While gelatin-based Fricke hydrogels are routinely used to measure radiation, these hydrogels are unstable at body temperature, and it is currently not possible to noninvasively measure radiation dose inside a patient. This study reports the synthesis and characterization of self-forming hydrogels containing Fricke components that are stable at body temperature. The …


Use Of Pulsed Electric Fields And Hydrogen Peroxide For Pre And Postharvest Strategies To Reduce Microbial Loads On Fresh Produce, Zachary Rosenzweig Sep 2024

Use Of Pulsed Electric Fields And Hydrogen Peroxide For Pre And Postharvest Strategies To Reduce Microbial Loads On Fresh Produce, Zachary Rosenzweig

Theses and Dissertations

Several issues exist within the agricultural industry surrounding failure to prevent pathogen transfer to plants preharvest and failure to decontaminate foods postharvest. Fresh produce, like leafy greens, pose a large threat to public safety if contaminated because they are minimally processed and often eaten raw. Numerous outbreaks have been linked to fresh produce in recent decades, with irrigation water emerging as a potential source. These outbreaks have severe economic repercussions and can contribute to millions of hospitalizations and deaths each year, worldwide. This thesis focuses on the usage of pulsed electric fields (PEF) and hydrogen peroxide (H2O2) as a means …


Experimental Investigations On Mechanical Wear And Corrosion Behaviour Of Sintered Atomet 4601 Based Hybrid Alloys, Palaksha Reddy K Sep 2024

Experimental Investigations On Mechanical Wear And Corrosion Behaviour Of Sintered Atomet 4601 Based Hybrid Alloys, Palaksha Reddy K

Theses and Dissertations

Powder metallurgy enables the development of new materials to manufacture products for applications requiring unique properties. The present research initially investigates the mechanical and tribological behaviour of powder metallurgy alloys made from ATOMET 4601 prealloyed powder and varying amounts of elemental carbon (0, 0.5, and 1.0 wt%) as reinforcement. ATOMET 4601 is a high-strength, water-atomized prealloyed powder capable of being compressed to higher densities, with applications in producing near-net or net-shaped parts for the industrial field.

Mechanical behaviour studies on sinter-forged ATOMET 4601, ATOMET 4601+0.5C, and ATOMET 4601+1.0C alloy steels revealed increased hardness, tensile strength, and impact strength, with ATOMET …


Nanofiber-Hydrogel Composite Scaffold Fabrication Methods For Peripheral Nerve Regeneration, Jacob Lee Carter Sep 2024

Nanofiber-Hydrogel Composite Scaffold Fabrication Methods For Peripheral Nerve Regeneration, Jacob Lee Carter

Theses and Dissertations

Nerve graft conduits (NGCs) are a rapidly advancing field for treating peripheral nerve injuries that aim to guide the growth of regenerating axons across damaged gaps. A more effective NGC can be manufactured by combining the use of nanofibers to act as guidewires within a 3-D hydrogel that imitates the extracellular matrix of nerve tissue. Several methods have been developed to embed aligned nanofibers in an ordered architecture within a hydrogel matrix. The first method involves layer-by-layer additive manufacturing to create NGCs with rows of polycaprolactone (PCL) nanofibers surrounded by a gelatin methacrylate (GelMe) hydrogel in a 3-D structure. A …


Prediction Of Moisture Resistance Of Aggregate Binder System Through Physicochemical And Mechanical Assessment, Khaja Sameer Sadat Sep 2024

Prediction Of Moisture Resistance Of Aggregate Binder System Through Physicochemical And Mechanical Assessment, Khaja Sameer Sadat

Student Theses and Dissertations

Moisture sensitivity has been a significant factor in pavement deterioration for several decades. The primary objective of the proposed research is to quantify the interface-level adhesion forces between bitumen samples and various types of aggregates. Aggregates and binders from varying sources with an anti-stripping agent were utilized for routine tests, micro-level tests, and elemental analysis. Pneumatic Adhesion Tensile Testing Instrument (PATTI) was discovered to be a more straightforward, simple, and repeatable adhesion testing method. The PATTI test revealed that sandstone exhibited higher adhesion values due to its greater porosity and absorption potential than limestone. The Texas Boiling test removed human …


Application Of Process Mining Algorithms To Surgical Training: A Study Of Healthcare Settings, Fazla Rabbi Sep 2024

Application Of Process Mining Algorithms To Surgical Training: A Study Of Healthcare Settings, Fazla Rabbi

Student Theses and Dissertations

Healthcare professionals must be experts at carrying out complex surgical procedures to fulfill their responsibilities. The aim of the medical treatments is fewer complications, shorter hospital stays, and a better patient experience. They often report on problems with surgical processes, skipped procedures, and lengthy transition times. The event log data allows process mining methods to deliver professionals with understandable findings using Petri Net. This study identifies the parallels and discrepancies between the pre-and post-stages and their respective frequency on each typical Central Venous Catheter (CVC) installation activity, where pre-stage they were given a briefing, and in post-stage they had hands-on …


Air Content Variation In Concrete At Different Stages Of Its Lifecycle, Mohammad Sarfaraz Uddin Sep 2024

Air Content Variation In Concrete At Different Stages Of Its Lifecycle, Mohammad Sarfaraz Uddin

Student Theses and Dissertations

In cold climates, concrete structures are susceptible to deterioration from the freezing and thawing of water within the concrete. The arrangement of air voids is crucial for the concrete to endure the freeze-thaw cycles. This research investigates changes in the air void system within concrete using a super air meter and the properties of both fresh and hardened concrete at various stages, including mixing and after pumping. Laboratory mixes used different dosages of air-entraining admixes and included Rice Husk Ash (RHA) as a supplementary material. Adding RHA to the mix resulted in a decrease in air content of about 2.2%, …


Development Of Bio-Based Organogels For The Replacement Of Silicone Elastomers In Cosmetic & Personal Care Applications, Courtney A. Lemasney Sep 2024

Development Of Bio-Based Organogels For The Replacement Of Silicone Elastomers In Cosmetic & Personal Care Applications, Courtney A. Lemasney

Theses and Dissertations

Silicone elastomers (SE) are a major component in many cosmetic and personal care products, providing excellent spreading properties, leaving a dry, silky feel on the skin. Unfortunately, the manufacturing of silicone is a high energy consuming process, and these products are not biodegradable. Capryloyl/glycerin/sebacic acid (CGS) copolymers are an economical, nontoxic platform for synthesizing bio-based materials with tailored properties. These polyester networks are formed through esterification with water as its only side product. By altering feed ratios and reaction conditions, final products can vary from branched fluids to highly crosslinked elastomers. This thesis investigated controlling the crosslink density of the …


Effective Integration Of Waste Plastics In Hot Mix Asphalt Mixtures: Towards Sustainable Infrastructure, Venkatsushanth Revelli Sep 2024

Effective Integration Of Waste Plastics In Hot Mix Asphalt Mixtures: Towards Sustainable Infrastructure, Venkatsushanth Revelli

Theses and Dissertations

The study investigated the potential of waste plastics such as low density polyethylene(LDPE), high density polyethylene(HDPE), polyethylene terephthalate(PET) and polystyrene (PS) for designing superior performing asphalt mixtures. Both wet mixing and dry mixing methods were adopted for designing plastic modified asphalt mixtures. Initially LDPE and HDPE were selected for developing plastic modified binders, based on melting characterization, determined from differential scanning calorimeter(DSC). In wet mixing process, the influence of dosage, size of plastic, blending duration and interaction between plastic and asphalt were assessed. Plastics were found to exhibit phase separation with asphalt, while finer particles take only longer to segregate …


Mechanical Behavior Of Nixcr Alloys With Ti3sic2 Nanoparticle Inclusions Using Molecular Dynamics, Brendan Martin Crutchfield Sep 2024

Mechanical Behavior Of Nixcr Alloys With Ti3sic2 Nanoparticle Inclusions Using Molecular Dynamics, Brendan Martin Crutchfield

Student Theses and Dissertations

Many materials used for solid lubrication are expensive and difficult to replace after abrasive wear, thus new compounds have to be considered and explored for their feasibility in solid lubrication. Nickel-chromium alloys are a potential replacement due to its high chemical and thermal stability, and Ti3SiC2 nanoparticle inclusions are considered to improve the wear rate of these materials. In this study, molecular dynamics (MD) simulations are utilized to assess the mechanical behavior of NixCr (x = 1, 2, 3, 4) alloys with and without Ti3SiC2 nanoparticle inclusions of radii 13, 20, and 27 Å. MD uniaxial tension tests are conducted …


Understanding And Enhancing Linux Kernel-Based Packet Switching On Wifi Access Points, Shiqi Zhang Sep 2024

Understanding And Enhancing Linux Kernel-Based Packet Switching On Wifi Access Points, Shiqi Zhang

Computer Science and Engineering Master's Theses

As the number of WiFi devices and their traffic demands continue to rise, the need for a scalable and highperformance wireless infrastructure becomes increasingly essential. Central to this infrastructure are WiFi Access Points (APs), which facilitate packet switching between Ethernet and WiFi interfaces. Despite APs’ reliance on the Linux kernel’s data plane for packet switching, the detailed operations and complexities of switching packets between Ethernet and WiFi interfaces have not been investigated in existing works. This paper makes the following contributions towards filling this research gap. Through macro and micro-analysis of empirical experiments, our study reveals insights in two distinct …


The Role Of Micromobility In The Changing Urban Mobility Landscape, Mostafa Jafarzadehfadaki Sep 2024

The Role Of Micromobility In The Changing Urban Mobility Landscape, Mostafa Jafarzadehfadaki

All ETDs from UAB

The growing prevalence of micromobility has significantly impacted urban mo-‎bility, offering a sustainable and convenient alternative for short trips in urban settings. ‎As cities grapple with increasing congestion, pollution, and the demand for efficient ‎mobility solutions, micromobility options like e-scooters and e-bikes have emerged as ‎popular modes of transportation, particularly in densely populated areas. While earlier ‎research has contributed to understanding micromobility and its impact on urban set-‎tings, significant knowledge gaps still exist. Therefore, a comprehensive study is neces-‎sary to explore the multifaceted dimensions of e-scooter adoption, usage patterns of mi-‎cromobility, and their implications for urban transportation systems and traffic …


Reduced Order Modeling (Rom) Using Machine Learning Techniques For Analyzing Fluid Flow Around A Ground Vehicle, Emmanuel Ong'aro Ramogi Sep 2024

Reduced Order Modeling (Rom) Using Machine Learning Techniques For Analyzing Fluid Flow Around A Ground Vehicle, Emmanuel Ong'aro Ramogi

All ETDs from UAB

Predicting wind and temperature fields around military vehicles during extended missions is crucial to avoid detectability by infrared (IR) devices. Also, the abrupt shifting of wind direction can have a significant impact on vehicle stability. This is a challenging task due to the vehicles' geometric complexity and the unpredictable nature of wind direction, which can shift abruptly. Computational Fluid Dynamics (CFD) is routinely used for calculating the flow fields around ground vehicles. However, this requires extensive computational time and memory, making it unsuitable for real-time analysis. To address these challenges, this research focuses on machine learning (ML) techniques for accurate …


Low-Power Sensor Design And Fusion To Edge Devices For High-Speed Object Detection And Enhanced Soldier Situational Awareness, Scott Patrick Wood Sep 2024

Low-Power Sensor Design And Fusion To Edge Devices For High-Speed Object Detection And Enhanced Soldier Situational Awareness, Scott Patrick Wood

Theses and Dissertations

Threat detection and physiological monitoring of soldiers from fused sensor data collected in real time is currently limited to running deep neural networks with substantial computing needs. The lack of data acquisition from sensor readings and efficient detection of novel enemy signatures motivates the need for a low-power, low-cost, wireless multisensor fusion computing system. We propose the current trends in Internet of Things to deploy a chargeable, wireless multi-channel acquisition system that can be interfaced to a high speed, Single Board Computer (SBC) such as the NVIDIA Jetson Orin capable of running object detection models, such as YOLOv7-tiny to enable …


Smart Toys For Sensing And Soothing Distress In Pediatric Patients, Jonathan Daniel Bonilla Sep 2024

Smart Toys For Sensing And Soothing Distress In Pediatric Patients, Jonathan Daniel Bonilla

Dartmouth College Master’s Theses

This thesis develops and evaluates child-centered technologies to support remote monitoring of pediatric patients, with an emphasis on childhood cancer and pediatric chronic pain. For these and many other health conditions, current therapies tend to focus on treating physical symptoms yet neglect the psycho-emotional aspects of managing the illness. However, such mental states play a major role in recovery. Research has shown that cancer patients with better mental health have better prognoses, higher possibilities of remission, and faster healing processes, while chronic pain patients with better mental health report lower levels of pain. To enable more personalized, continuous, and scalable …


Improved Parameters Of Anand Model And Advanced Fea Technique For Low-Cycle Fatigue Life: Finite Element Analysis Models For Pb-Free Solder And Pb Solder In Real Life Ball Gird Ally Package, Hamidreza Nahavandi Sep 2024

Improved Parameters Of Anand Model And Advanced Fea Technique For Low-Cycle Fatigue Life: Finite Element Analysis Models For Pb-Free Solder And Pb Solder In Real Life Ball Gird Ally Package, Hamidreza Nahavandi

Dissertations and Theses

The present study uses the finite element method to evaluate the fatigue life of solder joints of plastic ball grid array packages (PBGA) under thermal-cycling conditions. A Series of precise 3D FE models for solder joints of plastic ball grid array packages is created to improve reliability prediction accuracy. Damage parameters are obtained from the FEA results and used to estimate solder balls’ thermal fatigue life. The Coffin-Manson equation is employed. The predicted thermal fatigue lives are discussed in detail.

Due to marketing and legislative pressures, Pb-free solder is fast becoming a reality in electronic manufacturing. The industry has concluded …


Methods For Efficient Computation Of Neutron Multiplicity Distributions And Snm Sample Characterization, Jawad Ribhi Moussa Sep 2024

Methods For Efficient Computation Of Neutron Multiplicity Distributions And Snm Sample Characterization, Jawad Ribhi Moussa

Nuclear Engineering ETDs

This dissertation advances neutron multiplicity counting (NMC) by developing a hierarchy of computational methods that combine deterministic and stochastic techniques with modern machine learning for improved special nuclear material (SNM) characterization. A system state-updating Monte Carlo method is introduced in addition to a dynamic point kinetic model based on a backward Master equation (BME) formulation. These models, along with newly developed distribution reconstruction methods, enable more efficient computation of neutron count distributions in a fixed detector time-gate. NMC limitations associated with finite-size and neutron phase effects are also addressed by extending the BME model to account for time-gated neutron count …