Engineering Commons^™

Design Of Bamboo Reinforced Concrete Beams Considering Variability In Tensile Strength Of Bamboo, Bibek Bhardwaj, Michael Stoner, Weichiang Pang

Publications

In recent years, the price of steel has soared, making steel reinforcement in concrete structures unaffordable for households in low-income countries. Seismic activities in low-income households, particularly those in developing countries, pose a significant threat to life and property to unreinforced concrete structures. The application of bamboo as an alternative to steel in reinforced concrete is still in its early stages of development. Unlike steel, bamboo is a natural material, and its structural properties vary greatly based on species, location, age, and geometric properties. Thus, the design of bamboo-reinforced concrete involves more uncertainties than steel-reinforced concrete. This research investigates the …

Predicting Corrosion Damage In The Human Body Using Artificial Intelligence: In Vitro Progress And Future Applications Applications, Michael A. Kurtz, Ruoyu Yang, Mohan S. R. Elapolu, Audrey C. Wessinger, William Nelson, Kazzandra Alaniz, Rahul Rai, Jeremy L. Gilbert

Publications

Artificial intelligence (AI) is used in the clinic to improve patient care. While the successes illustrate the impact AI can have, few studies have led to improved clinical outcomes. A gap in translational studies, beginning at the basic science level, exists. In this review, we focus on how AI models implemented in non-orthopedic fields of corrosion science may apply to the study of orthopedic alloys. We first define and introduce fundamental AI concepts and models, as well as physiologically relevant corrosion damage modes. We then systematically review the corrosion/AI literature. Finally, we identify several AI models that may be Preprint …

On The Measurement Of Nakazima Testing Based Out-Of-Plane Forming Limit Curves Using 2d Digital Image Correlation, Akshat Agha, Fadi Abu-Farha

Publications

The strain compensation method for measuring in-plane forming limit curves (FLCs) using 2D digital image correlation developed previously [A method of measuring in-plane forming limit curves using 2D Digital Image Correlation, SAE Int. J. Mater. Manf., 2023] was modified and extended to more versatile and popular out-of-plane FLCs. The current study introduces a straightforward strain compensation technique for measuring Nakazima testing based out-of-plane FLCs utilizing an affordable single-camera (2D) DIC system. In this study, forming tests are performed on two automotive-grade sheet metal alloys: DP980 steel and a 6xxx series aluminum alloy using the Nakazima test method. The experiments are …

Composites 4.0: Enabling The Modernization Of Legacy Manufacturing Assets In South Carolina, Amit Makarand Deshpande, Gayatri Keskar, Sai Aditya Pradeep, Saeed Farahani, Srikanth Pilla

Publications

Composites 4.0 is the implementation of Industry 4.0 concepts to plastics and composites manufacturing with the goal to overcome the complexities associated with these materials. Due to very complex process-structure-property relationships associated with plastics and composites, a wide range of process parameters need to be tracked and monitored. Furthermore, these parameters are often affected by the tool and machinery, human intervention and variability and should thus, be monitored by integrating intelligence and connectivity in manufacturing systems. Retrofitting legacy manufacturing systems with modern sensing and control systems is emerging as one of the more cost-effective approaches as it circumvents the substantial …

Thermoplastics Foams: An Automotive Perspective, Sai Aditya Pradeep, Srishti Shukla, Nathaniel Brown, Srikanth Pilla

Publications

The automotive industry has witnessed a massive shift in terms of materials used, ranging from being a metallic heavyweight in the 1950s to employing a hybrid sandwich of multiple material systems. This apparent shift can be attributed to achieving improvements in performance, safety and fuel efficiency, along with responding to the various environmental regulations imposed by different governments. The recent advocacy of Corporate Average Fuel Economy (CAFE) standard of 54.5 MPG by 2025 by the US Environmental Protection Agency (EPA) to reduce greenhouse gas (GHG) emissions [1] has spurred the sector at large towards the use of lightweight materials.

A Protocol For Coupling Volumetrically Dynamic In Vitro Experiments To Numerical Physiology Simulation For A Hybrid Cardiovascular Model, Abraham Umo, Ethan Kung

Publications

Objective: The Physiology Simulation Coupled Experiment (PSCOPE) is a hybrid modeling framework that enables a physical fluid experiment to operate in the context of a closed-loop computational simulation of cardiovascular physiology. Previous PSCOPE methods coupled rigid experiments to a lumped parameter network (LPN) of physiology but are incompatible with volumetrically dynamic experiments where fluid volume varies periodically. We address this limitation by introducing a method capable of coupling rigid, multi-branch, and volumetrically dynamic in-vitro experiments to an LPN. Methods: Our proposed method utilizes an iterative weighted-averaging algorithm to identify the unique solution waveforms for a given PSCOPE model. We confirm …

Design And Development Of A Multi-Material, Cost-Competitive, Lightweight Mid-Size Sports Utility Vehicle’S Body-In-White, Amit M. Deshpande, Rushabh Rajesh Sadiwala, Nathan Brown, Sai Aditya Pradeep, Leon M. Headings, Ningxiner Zhao, Brad Losey, Ryan Hahnlen, Marcelo J. Dapino, Gang Li, Srikanth Pilla

Publications

Vehicle light-weighting has allowed automotive original equipment manufacturers (OEMs) to improve fuel efficiency, incorporate value-adding features without a weight penalty, and extract better performance. The typical body-in-white (BiW) accounts for up to 40% of the total vehicle mass, making it the focus of light-weighting efforts through a) conceptual redesign b) design optimization using state-of-the-art computer-aided engineering (CAE) tools, and c) use of advanced high strength steels (AHSS), aluminum, magnesium, and/or fiber-reinforced plastic (FRP) composites. However, most of these light-weighting efforts have been focused on luxury/sports vehicles, with a relatively high price range and an average production of 100,000 units/year or …

Numerical Implementation And Validation Of A Viscoelastic-Plastic Material Model For Predicting Curing Induced Residual Stresses In Adhesive Bonded Joints, Akshat Agha, Fadi Abu-Farha

Publications

One of the main challenges in the joining of multi-material components is the assessment of the nature and magnitude of the residual stresses developing in the adhesive bond during the heat curing manufacturing process. Numerical modeling of these residual stresses can provide insights for making informed decisions related to (i) material substrate properties; (ii) adhesive properties i.e., low, medium, or high stiffness; (iii) bondline geometry i.e., bondline width and bead thickness; (iv) curing cycle characteristics; and (v) fixation design i.e., type, spacing, the number of joints. This work presents a cure history-dependent viscoelastic-plastic material description for the modeling of adhesive …

Thermoforming Process Effects On Structural Performance Of Carbon Fiber Reinforced Thermoplastic Composite Parts Through A Manufacturing To Response Pathway, Madhura Limaye, Sai Aditya Pradeep, Anmol Kothari, Sushil Savla, Akshat Agha, Srikanth Pilla, Gang Li

Publications

Thermoforming process of thermoplastic-based continuous CFRP's offer a major advantage in reducing cycle times for large-scale productions, but it can also have a significant impact on the structural performance of the parts by inducing undesirable effects. This necessitates the development of an optimal manufacturing process that minimizes the introduction of undesirable factors in the structure and thereby achieves the targeted mechanical performance. This can be done by first establishing a relationship between the manufacturing process and mechanical performance and successively optimizing it to achieve the desired targets. The current study focuses on the former part, where a manufacturing-to-response (MTR) pathway …

Tunable Blood Shunt For Neonates With Complex Congenital Heart Defects, Ellen Garver, Christopher B. Rodell, Kristen Shema, Krianthan Govender, Samantha E. Cassel, Bryan Ferrick, Gabriella Kupsho, Ethan Kung, Kara L. Spiller, Randy Stevens, Amy L. Throckmorton

Publications

Despite advancements in procedures and patient care, mortality rates for neonatal recipients of the Norwood procedure, a palliation for single ventricle congenital malformations, remain high due to the use of a fixed-diameter blood shunt. In this study, a new geometrically tunable blood shunt was investigated to address limitations of the current treatment paradigm (e.g., Modified Blalock-Taussig Shunt) by allowing for controlled modulation of blood flow through the shunt to accommodate physiological changes due to the patient’s growth. First, mathematical and computational cardiovascular models were established to investigate the hemodynamic requirements of growing neonatal patients with shunts and to inform design …

Advanced Anti-Buckling Device Coupled With Real-Time Digital Image Correlation For Complex Cyclic Tension-Compression Testing Of Lightweight Materials, Akshat Agha, Fadi Abu-Farha

Publications

In sheet metal forming and stamping operations, modeling the behavior of sheet metal alloys for springback prediction is known to be very challenging, not only because of the complex models needed to account for kinematic hardening (such as the Yoshida-Uemori Model) but more importantly because of the experimental limitations of our ability to perform the complex tests needed to calibrate such models. For instance, reliable monotonic uniaxial compression tests and then cyclic tension-followed-by-compression tests are essential for characterizing the response of the material under those loading conditions, providing quantitative evaluation of the Bauschinger Effect and tension/compression asymmetry in the material, …

Pediatric Cardiac Devices: Recent Progress And Remaining Problems, Kyle Crawford, Martine Leberge, Dan Simionescu, Naren Vyavahare

Publications

Pediatric cardiology is a field that largely relies on translation of innovation in its adult counterpart in order to improve patient outcomes and introduce new technology to the field. Few FDA-approved pediatric cardiac devices are available for clinical use, thus leading to widespread off-label use within the field. Nonetheless, adaption of devices and technology from the adult field has proven to improve patient outcomes and overall wellness. However, the diversity of congenital heart disease, in terms of basic anatomy and treatment response, continues to complicate results. The combination of diversity of anatomy and small population size make it difficult for …

Systematic Review And Regression Modeling Of The Effects Of Age, Body Size, And Exercise On Cardiovascular Parameters In Healthy Adults, Aseem Pradhan, John Scaringi, Patrick Gerard, Ross Arena, Jonathan Myers, Leonard A. Kaminsky, Ethan Kung

Publications

Purpose

Blood pressure, cardiac output, and ventricular volumes correlate to various subject features such as age, body size, and exercise intensity. The purpose of this study is to quantify this correlation through regression modeling.

Methods

We conducted a systematic review to compile reference data of healthy subjects for several cardiovascular parameters and subject features. Regression algorithms used these aggregate data to formulate predictive models for the outputs—systolic and diastolic blood pressure, ventricular volumes, cardiac output, and heart rate—against the features—age, height, weight, and exercise intensity. A simulation-based procedure generated data of virtual subjects to test whether these regression models built …

Plaque Contact Surface Area And Flow Lumen Volume Predict Stroke Risk In Extracranial Carotid Artery Stenosis, Ryan Gendey, Ethan Kung, Veena Mehta, Adam Brown, Matthew Bridges, Ravi Veeraswamy

Publications

The standard indication for intervention in asymptomatic disease is currently percent stenosis in the internal carotid artery as measured by the NASCET method, which remains limited in discriminating power. CT angiography (CTA) is widely used to calculate NASCET stenosis but also offers the opportunity to analyze carotid artery plaques from a morphological perspective that has not been widely utilized. We aim to improve stroke risk stratification of patients with carotid artery stenosis using plaque 3D modeling and image analysis. Patients with CTAs appropriate for 3D reconstruction were identified from an NIH designated stroke center database, and carotid arteries were segmented …

Viscoelastic Model To Capture Residual Stresses In Heat Cured Dissimilar Adhesive Bonded Joints, Akshat Agha, Fadi Abu-Farha

Publications

The thermal loading during the curing process of an adhesive-bonded joint induces residual stresses in the joint, thereby affecting its performance. The problem becomes worse in the case of a multi-material joint involving varying coefficients of thermal expansion (CTE) for different parts. A novel approach was developed to model the properties of automotive grade structural adhesives during the heat curing process. The material model was divided into two components: curing kinetics model and viscoelastic mechanical model. The models were calibrated using experimental data from Differential Scanning Calorimetry (DSC) and Dynamic Mechanical Analysis (DMA) tests performed on an epoxy-based single-component adhesive. …

Stand-Alone Direct Current Power Network Based On Photovoltaics And Lithium-Ion Batteries For Reverse Osmosis Desalination Plant, Vishwas Powar, Rajendra Singh

Publications

Plummeting reserves and increasing demand of freshwater resources have culminated into a global water crisis. Desalination is a potential solution to mitigate the freshwater shortage. However, the process of desalination is expensive and energy-intensive. Due to the water-energy-climate nexus, there is an urgent need to provide sustainable low-cost electrical power for desalination that has the lowest impact on climate and related ecosystem challenges. For a large-scale reverse osmosis desalination plant, we have proposed the design and analysis of a photovoltaics and battery-based stand-alone direct current power network. The design methodology focusses on appropriate sizing, optimum tilt and temperature compensation techniques …

Hemodynamic Response To Device Titration In The Shunted Single Ventricle Circulation - A Patient Cohort Modeling Study, Chet Villa, Farha Zafar, Angela Lorts, Ethan Kung

Publications

Clinical outcomes of ventricular assist device (VAD) support for shunted single ventricle patients trail the larger population due in part to the challenges in optimizing VAD support and balancing systemic and pulmonary circulations. We sought to understand the response to VAD titration in the shunted circulation using a lumped-parameter network modeling six patient-specific clinical cases. Hemodynamic data from six patients (mean body surface area = 0.30 m²) with a systemic-to-pulmonary shunt was used to construct simulated cases of heart failure and hemodynamic response to increasing VAD flow from 5 to 10 L/min/m². With increasing VAD flow, …

Adaptive Signal System Safety Impacts Final Report, Mashrur Chowdhury, Weiman Jin, M. Sabbir Salek, Sakib Mahmud Khan, Katherine Brunk, Patrick Gerard, Nathan Huynh, Mohammad Torkjazi

Publications

The research team conducted a literature review and a nation-wide survey at the beginning of the research. The literature review revealed that Adaptive Signal Control System (ASCS) was effective in reducing crashes in some studies, while in other studies, the crash reduction due to ASCS was not statistically significant. Twenty-eight states participated in the nation-wide survey and helped the research team identify corridor characteristics, such as the design speed and Annual Average Daily Traffic (AADT) of an ASCS corridor, which would allow for the best operational and safety outcomes. Then, to determine the safety effects of ASCS, the research team …

Investigating The Impacts Of Crash Prediction Models On Quantifying Safety Effectiveness Of Adaptive Signal Control Systems, Weimin Jin, Mashrur Chowdhury, Sakib Mahmud Khan, Patrick Gerard

Publications

Introduction: Adaptive Signal Control System (ASCS) can improve both operational and safety benefits at signalized corridors. Methods: This paper develops a series of models accounting for model forms and possible predictors and implements these models in Empirical Bayes (EB) and Fully Bayesian (FB) frameworks for ASCS safety evaluation studies. Different models are validated in terms of the ability to reduce the potential bias and variance of prediction and improve the safety effectiveness estimation accuracy using real-world crash data from non-ASCS sites. This paper then develops the safety effectiveness of ASCS at six different corridors with a total of 65 signalized …

Design, Development And Temporal Evaluation Of An Mri-Compatible In-Vitro Circulation Model Using A Compliant Aaa Phantom, Mirunalini Thirugnanasambandam, Tejas Canchi, Senol Piskin, Christof Karmonik, Ethan Kung, Prahlad Menon, Stephanie Avril, Ender A. Finol

Publications

Biomechanical characterization of abdominal aortic aneurysms (AAA) has become commonplace in rupture risk assessment studies. However, its translation to the clinic has been greatly limited due to the complexity associated with its tools and their implementation. The unattainability of patient-specific tissue properties leads to the use of generalized population-averaged material models in finite element analyses, which adds a degree of uncertainty to the wall mechanics quantification. In addition, computational fluid dynamics modeling of AAA typically lacks the patient-specific inflow and outflow boundary conditions that should be obtained by non-standard of care clinical imaging. An alternative approach for analyzing AAA flow …

Experimental Methods To Capture Curing Induced Effects In Adhesive Bonded Joints, Akshat Agha, Fadi Abu-Farha

Publications

The rapidly increasing use of structural adhesives, especially in the joining of automotive body structures has motivated various investigations of the effects of adhesive curing process on joints. The automotive-grade structural adhesives require heat curing, which, in the meantime, performs thermal loading on the substrates and causes undesirable effects in the joint. For example, the curing process results in complex residual stresses in the adhesive bond which are detrimental to the performance of the adhesive bond and thereby the automobile body structure, particularly the crashworthiness. To thoroughly evaluate such effects, this paper consists of two parts. The first part presents …

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 …

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 …

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 …