Engineering Commons^™

A Comparison Of Methods To Measure Crop Water Use In South Carolina, Andrew C. Ewing

All Theses

The objective of this thesis was to compare cost-effective methods of measuring crop water use, known as evapotranspiration (ET), in South Carolina’s humid climate. The methods analyzed were the surface renewal method (SR), the Eddy Covariance method (EC), large in-field weighing lysimeters, a newly developed pressure differential device (PDD), a Class A Evaporation pan, and the Penman-Monteith equation. In the first chapter, ET measurements obtained by SR were compared to ET measured by EC and weighing lysimeters. For reference, EC and SR track the energy budget to estimate ET, while the weighing lysimeters used in this study are box-like containers …

Investigating The Presence Of Culture In Engineering Design: A Case Study On Culture In Design Methods, Perception, And Outcomes, Malena Ataa Durowaah Agyemang

All Dissertations

Overwhelming global statistics on economic, social, and health disparities has driven engineers and designers to develop solutions to minimize these disparities [1,2,11,12,3–10]. For the scope of this study, these efforts are referred to as design for humanitarian engineering and global development (HEGD). HEGD solutions are designed to improve access to medical technologies, energy, clean water, and even spark economic development [1–10]. However, many HEGD solutions go unadopted, halting their intended benefits [9,13,22,23,14–21]. Efforts to improve HEGD adoption have focused on ways to incorporate culture in the design solution’s aesthetics or in approaches post-deployment [24,25,34,35,26–33]. However, a review of failed HEGD …

Development And Application Of Sustainable Binders Comprising Of Fly Ash And Ground Glass Fibers In Portland Cement And Geopolymer Concrete, Omar Alsanusi Amer

All Dissertations

Since cement production is responsible for a significant share of anthropogenic CO2 emissions, the sustainability of concrete construction has become one of the most targeted research and construction industry goals. Many suggestions have been in use to encourage sustainability of concrete construction; one such approach is to partially replace cement by industrial byproducts. The most known industrial byproduct used in concrete construction worldwide has been fly ash, which is a byproduct of burning coal for power generation.

Fly ash use in concrete has various benefits. It reduces the water demand, reduces plastic shrinkage, reduces permeability, and thus improving the durability …

A Probabilistic Casualty Model To Include Injury Severity Levels In Seismic Risk Assessment, Weichiang Pang, S. Majdalaweyh, A. Safiey, K. Rokneddin, S. Prabhu, M. Javanbarg, E. Ziaei

Publications

Despite the increasing adoption of Performance-Based Earthquake Engineering (PBEE) in seismic risk assessment and design of buildings, earthquakes resulted in around 1.8 million injuries (three times the number of fatalities) over the past two decades. Several existing PBEE-based methodologies use rudimentary models that may not accurately estimate earthquake-induced casualties. Even when models are suitable for predicting the total number of fatalities and critical injuries, they may fail to adequately differentiate between different levels of injury severity. This paper draws attention to the importance of extending the seismic casualty assessment method by broadening the perspective on injury severity. To this cause, …

Investigating Hierarchical Effects Of Adaptive Signal Control System On Crash Severity Using Random-Parameter Ordered Regression Models Incorporating Observed Heterogeneity, Weimin Jin, Mashrur Chowdhury, M. Sabbir Salek, Sakib Mahmud Khan, Patrick Gerard

Publications

No abstract provided.

Ground Motion Duration Effects On The Seismic Risk Assessment Of Wood Light-Frame Buildings, Weichiang Pang, A. Safiey, S. Majdalaweyh, E. Ziaei, K. Rokneddin, M. Javanbarg

Publications

Wood construction comprises a large portion of building stocks of several countries across the globe with high preparedness for earthquakes including Japan, Canada, and the United States. Built environments of these countries are prone to long-duration ground shakings due largely to the proximity of subduction faulting systems. However, the current seismic design requirements do not adequately emphasize this key feature of ground motions. This study evaluates the impact of long-duration ground motions on seismic risk characteristics of code-conforming wood lightframe buildings. To this end, a study matrix of wood light-frame buildings is developed incorporating with two different heights (i.e., 1-story …

Photovoltaics- And Battery-Based Power Network As Sustainable Source Of Electric Power, Prahaladh Paniyil, Vishwas Powar, Rajendra Singh, Benjamin Hennigan, Pamela Lule, Matthew Allison, John Kimsey, Anthony Carambia, Dhruval Patel, Daniel Carrillo, Zachary Shriber, Truman Bazer, James Farnum, Kushal Jadhav, Dalton Pumputis

Publications

With the rise in the utilization of free fuel energy sources, namely solar and wind, across the globe, it has become necessary to study and implement models of a sustainable power network. This paper focuses on the design of a conceptual power network based on photovoltaics (PV) for power generation and lithium-ion batteries for storage. The power system showcases the various metrics that are involved in a grid-tied PV- and battery-based power network. It also encompasses the various design parameters and sizing considerations to design and conceptualize such a power network. The model focuses on the importance of the conservation …

Sharing Is Caring: Assessing Willingness To Share Autonomous Vehicles For Evacuation And Disaster Relief, Thomas Alan Shirley

All Theses

Coastal areas in the southeastern United States face the threat of hurricanes each year. Some of the greatest danger associated with these storms is experienced by citizens without personal means to evacuate. Along with storms comes the inevitable post-disaster relief process of evaluating losses and delivering supplies. With the rapid development of autonomous vehicle technology, this study examines the potential use of autonomous vehicles, publicly or privately owned, to assist in these evacuation and disaster relief efforts. Examining this new field of study, the researchers hosted three focus groups and received 1050 responses to an online survey. Based on the …

Production And Characterization Of Uranium Sol Gel Surrogates Produced With Cerium Acetate And Cerium Nitrate, Matthew Brett Alford

All Dissertations

For the production of ceramic microspheres for future space travel, new methods of processing must be explored. The sol gel method proves promising for the production of uranium-based ceramic microspheres that are consistent enough in size and shape for such an application. A process for producing these microspheres has already been established, but there are avenues for improvement.

Handling of radioactive material like uranium is not always possible or warranted. As such, a non-radioactive surrogate that greatly resembles the processing of its actual radioactive counterpart. Herein this work a cerium-based surrogate is developed to closely resemble an already established process …

Characterization Of Mechanical, Thermodynamic And Surface Properties Of The Butterfly Proboscis, Tatiana Stepanova

All Theses

The butterfly proboscis is a fascinating fiber designed to probe and transport fluids. The built-in sensors and actuators make this fiber multifunctional. The proboscis consists of 2 hollow C-shaped tubes that are united when the butterfly comes out of the pupa. A single galea consists of a solid cuticular wall, muscles, nerves, and tracheae. The proboscis cuticular wall is mainly composed of polymers and small amounts of metals and non-metals. The proboscis is a porous material, and its water content is high, up to 50%. When the butterfly is not hungry, its proboscis is tightly coiled; when the butterfly is …

Static Pressure Recovery Effects Of Conical Diffusers With Swirling Inlet Flow, James Ray Wright Iii

All Theses

Conical diffusers are used in hundreds of engineering applications in various industries. Some of the operating conditions that they operate under cause swirling flow to enter the diffuser. It is generally well documented that the addition of swirl to the flow of a diffuser allows for greater divergence angles without wall separation, resulting in better overall performance of the diffuser and the machine it’s attached to. It is also known that as swirl strength is increased, the flow will eventually breakdown, resulting in internal flow recirculation and decreased diffuser performance. However, the relationship between the diffuser geometry and its performance …

Delineating The Relationship Between Cardiovascular Physiology And Subject Characteristics Using Computational Modeling And Systemic Review, Aseem Pradhan

All Theses

Lumped Parameter Networks (LPN) are computational models that can capture the systemic responses of the cardiovascular system. An LPN describes the systemic behavior by providing outputs such as the blood pressure, flowrate, and heart chamber volume at the points defined in the network. To use the LPN for medical applications, it needs to provide output values that represent the physiology of realistic subjects. The cardiovascular system exhibits short-term and long-term adaptations to factors such as aging, weight gain, exercise, etc. Therefore, subject characteristics such as age, height, weight, etc. affect the output values of the LPN. Current literature reports the …

Mechanical Analysis Of Double Network Hydrogels To Determine Suitability As An Articular Cartilage Substitute, Casey Virginia Young

All Theses

The Center for Disease Control has found that between 2013-2015, 26% of women and 19% of men reported doctor-diagnosed cartilage disease or damage. Currently, there exists a substantial population with cartilage damage or disease needing a solution to increasing pain and decreasing function and mobility. Many of these individuals are young and thus looking for a treatment to delay a total knee replacement. Many others are elderly and thus looking to avoid major surgeries, as the riskiness of these procedures increases with age. As researchers look towards a method of cartilage replacement, hydrogels show measurable potential as a synthetic substitute …

Predictive Models For Pulmonary Artery Size In Fontan Patients, Akash Gupta, Chris Gillett, Patrick Gerard, Michael M.H. Cheung, Jonathan P. Mynard, Ethan Kung

Publications

We developed models of pulmonary artery (PA) size in Fontan patients as a function of age and body surface area (BSA) using linear regression and breakpoint analyses based on data from 43 Fontan patients divided into two groups: the extracardiac conduit (ECC) group (n = 24) and the non-ECC group (n = 19). Model predictions were compared against those of a non-Fontan control group (n = 18) and published literature. We observed strong positive correlations of the mean PA diameter with BSA (r = 0.9, p < 0.05) and age (r = 0.88, p < 0.05) in the ECC group. The absolute percentage differences between our BSA and age model predictions against published literature were less than 16% and 20%, respectively. Predicted PA size for Fontan patients was consistently smaller than the control group. These models may serve as useful references for clinicians and be utilized to construct 3D anatomic models that correspond to patient body size or age.

A Protocol For Automated A Posteriori Adaptive Meshing With Simvascular: A Test Case, Akash Gupta, Ethan Kung

Publications

Objective

Operational details regarding the use of the adaptive meshing (AM) algorithm available in the SimVascular package are scarce despite its application in several studies. Lacking these details, novice users of the AM algorithm may experience undesirable outcomes post-adaptation such as increases in mesh error metrics, unpredictable increases in mesh size, and losses in geometric fidelity. Here we present a test case using our proposed iterative protocol that will help prevent these undesirable outcomes and enhance the utility of the AM algorithm. We present three trials (conservative, moderate, and aggressive settings) applied to a scenario modelling a Fontan junction with …

Integration Concept Of Injection, Forming And Foaming: A Practical Approach To Manufacture Hybrid Structures, Saeed Farahani, Sai Aditya Pradeep, Srikanth Pilla

Publications

Motivated by the concept of the integrative production systems, the hybrid process of polymer injection molding and sheet metal forming, known as polymer injection forming (PIF), has been introduced to manufacture sheet metal-polymer components in a single operation. Despite the wide potential application of this technology, its implementation in actual industrial production has been hindered due to several challenges; a thick layer of polymer where there is deep deformation, non-uniform deformation due to pressure loss and the opposite phenomena of shrinkage and springback. To mitigate these practical issues, the novel idea of integrating supercritical fluid (Sc.F.) technology with the PIF …

Target Flow-Pressure Operating Range For Designing A Failing Fontan Cavopulmonary Support Device, Masoud Farahmand, Minoo N. Kavarana, Phillip M. Trusty, Ethan Kung

Publications

Fontan operation as the current standard of care for the palliation of single ventricle defects results in significant late complications. Using a mechanical circulatory device for the right circulation to serve the function of the missing subpulmonary ventricle could potentially stabilize the failing Fontan circulation. This study aims to elucidate the hydraulic operating regions that should be targeted for designing cavopulmonary blood pumps. By integrating numerical analysis and available clinical information, the interaction of the cavopulmonary support via the IVC and full assist configurations with a wide range of simulated adult failing scenarios was investigated; with IVC and full assist …

High Gravity Fermentation Of Sugarcane Bagasse Hydrolysate By Saccharomyces Pastorianus To Produce Economically Distillable Ethanol Concentrations: Necessity Of Medium Components Examined, Sarah W. Harcum, Thomas P. Caldwell

Open Access Publishing Fund

A major economic obstacle in lignocellulosic ethanol production is the low sugar concentrations in the hydrolysate and subsequent fermentation to economically distillable ethanol concentrations. We have previously demonstrated a two-stage fermentation process that recycles xylose with xylose isomerase to increase ethanol productivity, where the low sugar concentrations in the hydrolysate limit the final ethanol concentrations. In this study, three approaches are combined to increase ethanol concentrations. First, the medium-additive requirements were investigated to reduce ethanol dilution. Second, methods to increase the sugar concentrations in the sugarcane bagasse hydrolysate were undertaken. Third, the two-stage fermentation process was recharacterized with high gravity …

Risks And Benefits Of Using A Commercially Available Ventricular Assist Device For Failing Fontan Cavopulmonary Support: A Modeling Investigation, Masoud Farahmand, Minoo N. Kavarana, Ethan Kung

Publications

Fontan patients often develop circulatory failure and are in desperate need of a therapeutic solution. A blood pump surgically placed in the cavopulmonary pathway can substitute the function of the absent sub-pulmonary ventricle by generating a mild pressure boost. However, there is currently no commercially available device designed for the cavopulmonary application; and the risks and benefits of implanting a ventricular assist device (VAD), originally designed for the left ventricular application, on the right circulation of failing Fontan patients is not yet clear. Moreover, further research is needed to compare the hemodynamics between the two clinically-considered surgical configurations for cavopulmonary …