The surgical standard of care to partially restore grasping function after a traumatic spinal cord injury is a reconstructive tendon transfer-surgery that connects all four finger flexors to an expendable wrist extensor. While restorative, this surgery has a fundamental problem; the movement of all four fingers flexors is directly coupled,...
Airborne Wind Energy System (AWES) are quickly coming to fruition, with increased energy production while reducing the cost of implementation and materials. This thesis develops a new computational model for a tethered AWES and characterizes a new rapid prototyping method with the objective of supporting the design and rapid prototyping...
Time-dependent crack growth mechanisms in Alloy 617 at 800°C in air were studied using compact tension samples machined in the L-T direction, cracked at temperature using an induction furnace and servo-hydraulic load frame. The application of different loading waveforms, including triangular, hold time, and sustained loading, were studied with relation...
Shoulder injuries, especially those caused by rotator cuff tears, are a pervasive problem in human and canine patients. The ability to quickly and accurately diagnose rotator cuff tears is important for early and targeted treatment. Prior clinical work has demonstrated that ultrasound and magnetic resonance imaging effectively diagnose these tears....
Wood composites are an important renewable structural material which can be a net carbon sink when used in combination with sustainable forest management practices and high rates of log utilization. Adhesive bondlines are an essential part of composites, and for wood composites, they determine the moisture durability and mechanical performance...
Bulk metallic glasses (BMGs) offer a great deal of potential through their near-theoretical strength, potentially high toughness and unique forming and molding traits. However, there are still a number of outstanding issues that bar their widespread use. This thesis describes the investigation of three research questions each designed to further...
Toughened ceramics, or bridging ceramics, are being developed in an attempt
to widen the application base of traditional ceramics, which are brittle and have low
resistance to crack extension. The crack growth resistance of these extrinsically
toughened ceramics has been shown to increase with crack length, and unlike
traditional ceramics,...
A backward fall is a major cause of hip fractures. Hip fractures have the potential to increase the mortality rate of older adults. Thus, the prevention of backward falls by older adults is a critical subject to be studied. Specifically, it remains unknown what effect aging-related losses in muscle strength...
Thousands of children and adults suffer from fine motor skill deficits due to developmental disabilities or brain trauma. In order to acquire or reclaim these precision motor movements, occupational therapists work closely with each patient to develop the muscle memory required for completing tasks such as handwriting or drawing. Although...
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BrianK. Bay
Thousands of children and adults suffer from fine motor skill deficits due to
Because of its attractive material properties like high hardness, high toughness, and excellent high temperature strength, materials like silicon nitride are becoming more common for use in high performance applications. However, there have been limited studies of the fatigue behavior of small cracks in silicon nitride and other materials toughened...
Non-destructive testing methods and applications have become of increasing interest due to the worldwide aging and deteriorating infrastructure network. In the field of Civil Engineering, bridges and bridge components as well as non-structural elements such as roadway pavements for example, are affected. In particular, the Acoustic Emission (AE) technique offers...
Ever since composite laminate technology was introduced into the aerospace and automotive industry, there has been a need to fully understand the damage progression experienced by composite laminated plates in the presence of a notch. While numerous research studies have been conducted on this matter when subjected to in-plane loads,...
Many conventionally reinforced concrete deck girder (RCDG) bridges were built in the US during the 1950s, throughout the expansion of the Interstate System. Designs followed the AASHO standard of the time, which permitted higher shear stress in concrete and reduced detailing requirements than permitted by current specifications. Many of these...
Hydrogels have been proposed as candidates for nucleus pulposus replacement due to
their similarity in mechanical behavior to the native tissue when subjected to transient or
static loading; however, given the viscoelastic nature of soft biological tissues, the lack of
dynamic testing is a significant inadequacy in the studies performed...
The electrical conductivity data of ceramic material at high temperatures can be useful in the application of modeling, solid oxide fuel cell (SOFC), and magnetohydrodynamic (MHD). The existing data is considerably lacking at extreme temperatures. Our research focuses on bridging this gap by reporting the electrical conductivity measurements of sets...
Metallic glasses (also referred to as amorphous metals) have been gaining interest in the materials science community in recent years. These amorphous materials demonstrate promising properties compared to their crystalline counterparts that include much higher strength and elastic strain limit, better corrosion and wear resistance, superior soft magnetism, and an...
Visitors to waterways need a way to securely lock up their non-motorized watercrafts to allow for exploration of the local area and communities. The Willamette Water Trail Steering committee recognized this problem and approached the Oregon State University Prototype Development lab to develop and fabricate a solution. The engineering design...
As designers continue to develop the ability to improve a component or system design relative to any number of metrics, priorities and objectives, the need for advanced methodologies which focus efforts and steer design decisions to best meet the needs of the organization becomes increasingly important. This work develops such...
In anatomical education, clinicians, surgeons, and anatomists support the use of human cadavers over digital or artificial alternatives. Cadaver use raises the challenge of preventing tissue dehydration. The OSU cadaver labs attempt to maintain hydration by re-covering the exposed tissues with original skin, layers of plastic wrap, and/or towels and...
In order to generate practical ways to easily design functional flexible lattice structures, this research seeks to find a way to predict reactive forces of compressed hyperelastic cubic lattice structures. Using 3D printed test coupons, material data was collected for use in finite element analysis. Cubic lattice structures with varying...
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BrianBay, Committee Member, representing School of Mechanical, Industrial, and Manufacturing
Degeneration of the intervertebral disc (IVD) is a phenomenon that has yet to be adequately addressed. Treatment options remain limited and incomplete. The ability to effectively cryopreserve IVDs would allow for better allograft transplantations and storage of samples for research purposes. This study aimed to assess how cryopreservation with different...
Chain saws are a common tool used by large logging corporations and family homesteads to manage forests, limb trees and buck lumber. A significant cost of operation is the continuous required supply of bar and chain oil. Consumers and logging corporations desire a lubricant with a high performance to cost...
Flexible aerodynamic surfaces have been shown to favorably influence flight characteristics at low Reynolds numbers by increasing lift, angle of attack at stall, and resistance to perturbation. The objective of the research presented within this thesis is to investigate the influence of two aspects of flight observed in biological flyers,...
Identifying material parameters in composite plates is a necessary first step in a variety of structural applications. For example, understanding the material parameters of carbon fiber composite is important in investigating sensor and actuator placement on micro-air-vehicle wings for control and wing morphing purposes. Knowing the material parameters can also...
Driven by the need for high energy-density power sources, demand has
stimulated the development of small-scale engines. A small-scale engine
with a fuel supply could replace batteries and utilize higher energy-density
liquid hydrocarbon fuels; such an advance could deliver a new age of
portable devices. Currently, operable small-scale engines exist;...
Fiber reinforced polymers have gained considerable attention due to their wide range of applications, leading to significative concerns for end-of-life recyclability and disposal. Natural fibers and recycled carbon fibers, coupled with thermoplastic matrices can provide a sustainable and environmentally friendly alternative to traditional materials.
This study focused on experimental materials...
In order to solve some classic problems in traditional topology optimization, such as unknown material distribution, checker-boarding and curse of dimensionality, this thesis introduces a new method to construct a mechanical structure that can reduce mass and increase stiffness. It uses a graph to represent the skeleton of a structure....
Composites often are able to carry more load after damage due to the structure of laminates. In addition, damage can be difficult to detect in composites compared to homogeneous materials. Understanding the behavior of composite material after damage is vital for composite structural design. Currently, experimental methods exist for classifying...
Cutting operations using blades appear in several different industries such as food processing, surgical operations, gardening equipment, and so forth. As our society continues to increase our technological prowess, there is an ongoing need to better understand the underlying causes of simple tasks such as cutting so that cutting operations...
Since the 1970s, tendon-transfer surgeries have been routinely performed for a variety of conditions such as stroke, paralysis, spinal atrophy, trauma, and birth defects. The surgery involves rerouting a tendon from a disabled muscle and directly suturing it to a functioning muscle in order to partially restore hand function. This...
The use of adhesives in demanding engineering applications is a very common
occurrence in the modern world. These adhesives are taking the role of many traditional
fasteners, especially in the area of fiber reinforced composites. As the use of these
adhesives become more common place, better understanding of their mechanics...
Among the many safety hazards facing chainsaw operators, the phenomenon known as kickback is the most dangerous. Kickback occurs when the chain at the tip of the chainsaw is caused to stop abruptly, and transfers the energy of the cutting chain to motion of the saw. The saw will rotate...
A lightweight carbon fiber reinforced polymer (CFRP) c-channel beam was previously designed using analytical theory and finite element analysis and subsequently manufactured through a pultrusion process. Physical testing revealed the prototype did not meet the bending and torsional stiffness of the beam model. An investigation revealed that the manufactured prototype...
With growing concerns on environment impact of industrial product development, the product developers are seeking better solutions to achieve desired environmental benign requirements by the regulators and customers besides economic growth. During the last decade, some of the most successful product development companies (such as HP) have established their own...
Computing agents require state information to make coherent and useful decisions. A state representation is a numerical translation of the environment and conditions that are pertinent factors in an agent's decision making. Although many representations, when paired with clever learning algorithms, are able to coordinate and capture prey in specific...
Biocompatible hydrogels composed of covalently crosslinked, chemically modified hyaluronan (HA), gelatin (Gtn), and heparin (Hp) were synthesized for controlled release of human vascular endothelial growth factor (VEGF) or basic fibroblast growth factor (bFGF). We hypothesized that inclusion of small quantities of heparin in these gels would result in regulated growth...
Back pain is the leading cause of disability worldwide, entailing a significant socioeconomic impact. A primary source of back pain can be attributed to intervertebral disc (IVD) degeneration allowing nerve ingrowth, facet joint arthritis, disc bulging, and osteophyte formations that press on nearby nerve roots or the spinal cord. While...
This dissertation demonstrated that the electrical properties of complex oxide-based perovskite materials could be controlled through the careful modification of both material composition and structure. This was first shown through the modification of lead zirconate titanate (Pb(Zr0.52Ti0.48)O3, PZT) solid solutions with bismuth indate (BiInO3, BI) where the relative stability of...
Structural Health Monitoring (SHM) is known as the process of implementation of damage detection and characterization strategy. The method is widely used in modern critical equipment to minimize the risk of failures. While a significant effort has been devoted by researchers for the detection of faults in situations including periodic...
The study outlined in this dissertation elucidate the thermal and structural properties of ZrB2 based ceramics as choice materials for high temperature applications. Thermal properties were investigated to improve understanding on aspects that are affected by point defects and impurities at nanoscale and electron level using a combination of lattice...
The primary purpose of the present study is to explore the effect of wearing the hijab in a Western society on Muslim women’s well-being, their motivation to wear it, and the different modifications that they have made on their hijabs. To investigate the relationship between the hijab and Muslim women’s...
The objective of this paper is to demonstrate a method for mechanically characterizing a 25 μm thick elastoviscoplastic hemodialysis membrane and for quantifying the force required to use that membrane in compression sealing. First, methods are developed for mechanically characterizing the thin elastoviscoplastic membrane. Then, a finite element model is...
Engineers have long been inspired by nature's flyers. Such animals navigate complex environments gracefully and efficiently by using a variety of evolutionary adaptations for high-performance flight. Biologists have discovered a variety of sensory adaptations that provide flow state feedback and allow flying animals to feel their way through flight. A...
Little, if any, quantifications have been made on the contribution of the vertebral column during jumping in quadrupedal mammals. Previous studies of jumpers have focused on the morphological and physiological specializations of the hindlimbs. In this study, such specialization was measured during the supramaximal jumps of the Pacific jumping mouse...
Grapes (e.g. Vitis vinifera L.) are one of the more important fruit crops from an economic standpoint with world market values over 550 million US dollars in 2007 and 2008, second to apples (United States Department of Agriculture). While a satisfactory level of ripeness is of primary concern, the quality...
The importance of wood bonding increased in the last decades due to the
increased usage of wood composites whose performance depends to a large extent on
the adhesive penetration and subsequent bonding of the adherends. The presented
research used XMT (x-ray microtomography) to perform a non-destructive, threedimensional
analysis of the...
Although female athletes are at greater risk of non-contact knee injuries than men, the factors that contribute to these injuries are not well understood. One important question is whether intense exercise influences the risk of knee injury, both acutely
and over the following days. The purpose of this study was...
Selective laser melting (SLM) is an additive manufacturing (AM) process that uses a laser beam to melt metal powder as it is spread onto the build surface using a roller or scraper, followed by rapid solidification to manufacture a 3D component, one layer at a time.
In SLM process, density...
Creating effective packaging is about finding a balance between product protection during shipping and time consumption in the design process. Given time and cost constraints, it is hard to produce sufficiently protective padding while having it not be thicker than it needs to be. This thesis describes a method to...
Manufacturing exists as a stronghold for continuous growth and development of economies, a trend that is likely to continue as the demand for commodities and products grow. Manufacturing drives innovation and productivity in developed nations, as well as promoting economic stability and development in developing nations. However, manufacturing activities pose...