Engineering Commons^™

A Hybrid Experimental‐Computational Modeling Framework For Cardiovascular Device Testing, Ethan Kung, Masoud Farahmand, Akash Gupta

Publications

Significant advances in biomedical science often leverage powerful computational and experimental modeling platforms. We present a framework named physiology simulation coupled experiment (“PSCOPE”) that can capitalize on the strengths of both types of platforms in a single hybrid model. PSCOPE uses an iterative method to couple an in vitro mock circuit to a lumped-parameter numerical simulation of physiology, obtaining closed-loop feedback between the two. We first compared the results of Fontan graft obstruction scenarios modeled using both PSCOPE and an established multiscale computational fluid dynamics method; the normalized root-mean-square error values of important physiologic parameters were between 0.1% and 2.1%, …

Situation-Aware Left-Turning Connected And Automated Vehicle Operation At Signalized Intersections, Sakib Mahmud Khan, Mashrur Chowdhury

Publications

One challenging aspect of the Connected and Automated Vehicle (CAV) operation in mixed traffic is the development of a situation-awareness module for CAVs. While operating on public roads, CAVs need to assess their surroundings, especially the intentions of non-CAVs. Generally, CAVs demonstrate a defensive driving behavior, and CAVs expect other non-autonomous entities on the road will follow the traffic rules or common driving behavior. However, the presence of aggressive human drivers in the surrounding environment, who may not follow traffic rules and behave abruptly, can lead to serious safety consequences. In this paper, we have addressed the CAV and non-CAV …

Implementing Unbiased Decision-Making In Construction: A Lean Approach, Somik Ghosh, Michelle Robinette, Howard Tapia

The Professional Constructor

Construction project-teams are frequently faced with the task of decision-making as part of their responsibility. The positive effects of the decisions made at various stages of the projects lead to improved project performances, while negative effects can hinder the performances. The project teams take up the task of decision-making surrounded by multiple criteria, which can be arduous and clouded with subjectivity. This paper presents an approach based on the Lean principle of providing more autonomy to the project-teams and supporting collaborative and decentralized process in pursuit of unbiased decision-making. This Lean way of decision-making is formalized as Choosing by Advantage …

Attracting And Retaining Future Top Performing Employees: A Student Perspective, Julia Allen

The Professional Constructor

This essay provides insight as to how construction companies can both attract and retain top performing employees. By making the standard interview and recruiting processes more personal, construction companies can evaluate potential hires to see is they are a good fit for the company for years to come. Once employees are hired, companies then need to provide opportunities for both personal and professional growth. From personal experiences, I share the characteristics I find most important in an ideal employer and emphasize the importance of having an in-depth, genuine conversation with potential hires.

Attracting And Retaining Top Employees By Placing Proper Value On Their Contribution To The Company, Joseph Franklin Iii

The Professional Constructor

Due to an optimistic economic future, construction companies want to attract and retain the best employees to ensure company success. Because of a larger job market, employees now look for the optimal work values to be met in long-term employment opportunities. Construction companies have many challenges when attracting and retaining top employees in a growing market. Therefore; it is beneficial for employers to consider the evolving work values of employees and for these values to be promoted throughout company culture. Offering employees good value for their contribution to the company attracts and retains top employees.

Social Resources Of Mechanical Contracting Management Personnel, Blake Wentz, Sarabeth Gandara

The Professional Constructor

The construction industry in the United States is projected to grow faster than average compared to other industries through 2026. The Baby Boomer generation is leaving a significant gap in the labor force as they reach retirement. Retention of high quality management personnel is a priority for all companies in the construction industry, including mechanical contracting companies. Firms that fail to retain these employees will be left with an understaffed and underqualified workforce, which will hinder their ability to be competitive in the marketplace. In order to aid in retention efforts, mechanical contracting firms need to focus their attention on …

Essay Winners, American Institute Of Constructors

The Professional Constructor

No abstract provided.

Attracting And Retaining Future Top Performing Employees, Caleb Bardin

The Professional Constructor

The goal of this essay is to explore the key factors that influence top-performing employees’ decisions to change companies or remain with their current employers. A few of these factors are salary and benefits, work environment, and corporate advancement. This essay will address such factors and propose solutions using my own educational and professional experience. A key theme to note is the constant evaluation of employees and workplace environment by employers. No company can hope to be successful or have the best people if this skill is not enhanced and implemented well.

Study Of Various Construction Job Functions To Address Workforce Challenge, Abraham Bonilla, Dhaval Gajjar, Kenneth Sullivan

The Professional Constructor

Lack of construction workforce is one of the most predominant challenges faced by the construction industry. It is predicted that the industry will have a major shortage of skilled labor in the next decade due to the retirement of baby boomers and the lack of new talent entering the industry to replace these baby boomers. To attract young talent into the construction industry, it is critical to make them aware about the industry regarding various job functions as it relates to job satisfaction, compensation and career fulfilment. The purpose of this study is to gain insight of various construction job …

Consumer Perception And Willingness To Pay For Extended New Home Warranties, C. Todd Usher, Joseph M. Burgett

The Professional Constructor

Construction standards and methods for building new homes has improved over the last two decades resulting in significant improvements in energy efficiency, comfort, indoor air quality, and durability of new homes. Despite these improvements, the most common builder warranty for a new home in the United States ranges from 6 months to two years in duration. During the past two decades, manufacturer warranties on other durable goods such as automobiles has increased significantly. This study measures consumer perceptions of extended 12 year new home warranties with a survey completed by 162 adults in the United States. The results indicate that …

(Invited) Emerging Role Of Silicon Carbide And Gallium Nitride Based Power Electronics In Power And Transportation Sectors, Prahaladh Paniyil, Rajendra Singh

Publications

Free fuel-based energy sources (solar and wind) are pointing towards a future in which sustainable energy is affordable, abundant and deployed with high energy efficiency. Driven by advancements in the technology of lithium batteries and the availability of low-cost sustainable clean electric power, the electrification of transportation is going through fundamental disruptive transformation. Without any doubt, both power and transportation sectors will provide phenomenal growth of power electronics in the 21st century. Recently, both SiC and GaN are drawing the attention as potential replacement of Si-based power electronics. These may open some new markets where Si based power electronics cannot …

Fiber Element-Based Nonlinear Analysis Of Concrete Bridge Piers With Consideration Of Permanent Displacement, Mokhtar Ansari, Farhad Daneshjoo, Amir Safiey, Naser Safaeian Hamzehkolaei, Maryam Sorkhou

Publications

Utilization of fiber beam-column element has gained considerable attention in recent years due mainly to its ability to model distributed plasticity over the length of the element through a number of integration points. However, the relatively high sensitivity of the method to modeling parameters as well as material behavior models can pose a significant challenge. Residual drift is one of the seismic demands which is highly sensitive to modeling parameters and material behavior models. Permanent deformations play a prominent role in the post-earthquake evaluation of serviceability of bridges affected by a near- fault ground shaking. In this research, the influence …

Design And Analysis Of A Single Stage, Traveling Wave, Thermoacoustic Engine For Bi-Directional Turbine Generator Integration, Mitchell Mcgaughy

All Theses

The demand for clean, sustainable, and cost-effective energy continues to increase due to global population growth and corresponding use of consumer products. Thermoacoustic technology potentially offers a sustainable and reliable solution to help address the continuing demand for electric power. A thermoacoustic device, operating on the principle of standing or traveling acoustic waves, can be designed as a heat pump or a prime mover system. The provision of heat to a thermoacoustic prime mover results in the generation of an acoustic wave that can be converted into electrical power.

Thermoacoustic devices offer highly reliable and transportable power generation with low …

Polymer Injection Forming: A New Age Technology For Manufacturing Polymer-Metal Hybrids, Saeed Farahani

All Dissertations

Due to global competition, manufacturing firms in high-wage countries must target innovation in production processes and technologies that allow the mass manufacturing of customized products through highly efficient processes. Motivated by the concept of the integrative production systems, 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 using a single tooling, machinery, and operating system. During this process, the sheet metal blank inside the injection mold is deformed by means of tool movement and/or by pressure of the polymer melt. As the melt cools, the …

Chemically Active Rheological Modifiers For The Improved Clinical Use Of Cyanoacrylates, Kyle Joseph Garcia

All Dissertations

Over 100 million surgical incisions, 50 million traumatic wounds, and 20 million minor lacerations from cuts and grazes are treated globally each year. One study determined that globally internal and external wounds occur for 40% and 37% of cases respectively for a total of 111 million patients that were treated for wounds. The remaining 23% of patients were treated for minor lacerations and trauma in the emergency room. These wounds require immediate medical attention including pressure application, sutures, clips, tissue cautery, and/or topical hemostatic agents to cease hemorrhage or the exit of other bodily fluids. With blood flow ceased, wound …

Investigation Of Carrier Density And Mobility Variations In Graphene Caused By Surface Adsorbates, Hongmei Li, Xu Han, Anthony C. Childress, Apparao M. Rao, Goutam Koley

Publications

Conductivity, carrier concentration and carrier mobility in graphene were investigated as a function of time in response to ionized donor and acceptor adsorbates. While a reduction in conductivity and hole density in graphene was observed upon exposure to a weak electron donor NH₃, the carrier mobility was found to increase monotonically. The opposite behavior is observed upon exposure to NO₂, which is expected based on its typical electron withdrawing property. Upon exposure to C₉H₂₂N₂, a strong donor, it resulted in the transformation of graphene from p-type to n-type, although …

Development Of Statewide Annual Average Daily Traffic Estimation Model From Short-Term Counts: A Comparative Study For South Carolina, Sakib Mahmud Khan, Sababa Islam, Md Zadid Khan, Mashrur Chowdhury, Nathan Huynh, Mohammad Torkjazi

Publications

Annual Average Daily Traffic (AADT) is an important parameter for traffic engineering analysis. Departments of Transportation continually collect traffic count using both permanent count stations (i.e., Automatic Traffic Recorders or ATRs) and temporary short-term count stations. In South Carolina, 87% of the ATRs are located on interstates and arterial highways. For most secondary highways (i.e., collectors and local roads), AADT is estimated based on short-term counts. This paper develops AADT estimation models for different roadway functional classes with two machine learning techniques: Support Vector Regression (SVR) and Artificial Neural Network (ANN). The models predict AADT from short-term counts. The results …

A Mathematical Remodeling For Crop Portfolio Selection Under Limited Irrigation Resource, Li Zhang

S.C. Water Resources Conference

A mathematical model and optimization framework to aid farmers in selecting crop portfolios were proposed and discussed in (Bokhira et al. 2014; Chrispell et al. 2012). In this paper, we propose a refined mathematical model which reduces the number of constraints by nearly half while the number of decision variables is about the same. Also, the proposed model is easier to implement and maintain due to its generalized structure, and it provides more flexibility for us to expand the problem. Some key sensitive analysis is also provided.

The Professional Constructor, Full Issue, Volume 43, Number 02

The Professional Constructor

No abstract provided.

Examining The Microeconomics Of Bid Difference Of Engineer & Contractor Bids In Highway Construction, Robert Ryan, Randy R. Rapp, Mark Shaurette, Sarah Hubbard

The Professional Constructor

This study examines microeconomic factors that affect Bid Difference between the designer’s Engineer’s Estimate and the contractor’s Winning Bid. Historically, the accuracy of the Engineer’s Estimate and the Winning Bid vary. To account for this discrepancy, the Federal Highway Administration (FHWA) recommends a contingency be included in all Engineer’s Estimates. Statistical analysis was performed to determine if state Departments of Transportation (DOTs) were currently meeting the recommended Bid Difference values. Data was collected from California, North Carolina, and Ohio from 2012 through 2014. Statistical analysis indicates that current practices to develop an Engineer’s Estimate met the FHWA recommended values. With …

Designing A Modular Building: A Case Study For Modular Vs.Conventional Design For An Apartment Building, Christine Piper, Arun Thodupunoori

The Professional Constructor

To alleviate the diminishing number of tradespeople in the US construction industry, modular construction is an alternative construction process that could be used for repetitive construction applications. However, there are some misconceptions about modular construction including: limited architectural design options, design restrictions, lower quality, unaffordable and inability to design for sustainability. Modular construction is a process that streamlines the construction process and saves a significant amount of time while delivering a high quality building. In response to the misconception of design options, this case study presents the design considerations for transforming an apartment building that was designed and constructed using …

Application And Usage Of Design-Build By State Dots, Dennis Bausman, Mashrur Chowdhury, Christopher Cummings, Sasi Selvan

The Professional Constructor

This study examines the usage of design-build by the Department of Transportation (DOT) of the 50 states in the United States. Design-build has been growing in popularity as a procurement form in both the private and public sectors, and in the last ten years many DOTs have started or expanded programs to use design-build for infrastructure projects. However, many DOTs are still struggling to determine the best application of design build and how to incorporate its use as a procurement method for DOT projects. This study examines how state DOTs are using design-build, when they are using this delivery method, …

Assessment Of Electrical Contractors’ Perception And Practices With Project Risk Management, Anthony J. Perrenoud

The Professional Constructor

Project Risk Management is a critical construction management skillset for identifying risks, assessing risks, strategizing, and executing risk mitigation plans. Proactive risk management has been found to reduce negative impacts to project objectives and increase customer satisfaction. To improve project risk management contractors have a method of measuring perceptions and practices of risk management, also known as risk maturity. Previous research has identified a model for measuring five major attributes of risk maturity they are (1) management’s perspective of risk management; (2) organizational risk culture; (3) risk identification; (4) risk analysis; and, (5) standardized risk management process. This study presents …

Collaborative Risk Mitigation Through Construction Planning And Scheduling, Lane Kay Coble

The Professional Constructor

No abstract provided.

Construction Disputes In The United States And The United Kingdom: A Comparison, Anusree Saseendran, Ben F. Bigelow, Zofia Rybkowski, Dawn Jourdan

The Professional Constructor

Construction disputes are on the rise globally. They adversely affect the progress and quality of a construction project by resulting in cost overruns and delays. They are also time-consuming and expensive to resolve. Hence it is valuable to identify the most disputed topics in construction in the US and compare them to those in a different country. This helps better understand disputes, and the influence that culture and the difference in the nature of construction in the regions may have on disputes. This study was an attempt to identify and compare the most disputed topics in construction in the United …

Evaluation Of Seismic Performance Of Mid-Rise Reinforced Concrete Frames Subjected To Far-Field And Near-Field Ground Motions, Mokhtar Ansari, Masoud Ansari, Amir Safiey

Publications

Damages to buildings affected by a near-fault strong ground motion are largely attributed to the vertical component of the earthquake resulting in column failures, which could lead to disproportionate building catastrophic collapse in a progressive fashion. Recently, considerable interests are awakening to study effects of earthquake vertical components on structural responses. In this study, detailed modeling and time-history analyses of a 12-story code-conforming reinforced concrete moment frame building carrying the gravity loads, and exposed to once only the horizontal component of, and second time simultaneously the horizontal and vertical components of an ensemble of far-field and near-field earthquakes are conducted. …

Mechanically Assisted Electrochemical Degradation Of Alumina-Tic Composites, Hetal Umesh Maharaja, Guigen Zhang

Publications

Alumina-TiC composite material is a tough ceramic composite with excellent hardness, wear resistance and oxidation resistance in dry and high-temperature conditions. In aqueous conditions, however, it is likely to be electrochemically active facilitating charge transfer processes due to the conductive nature of TiC. For application as an orthopedic biomaterial, it is crucial to assess the electrochemical behavior of this composite, especially under a combined mechanical and electrochemical environment. In this study, we examined the mechanically assisted electrochemical performance of alumina-TiC composite in an aqueous environment. The spontaneous electrochemical response to brushing abrasion was measured. Changes in the magnitude of electrochemical …

Highway Cross Slope Measurement Using Airborne And Mobile Lidar, Alireza Shams Esfandabadi

All Dissertations

Ensuring adequate pavement cross slope on highways can improve driver safety by reducing the potential for water sheeting and ponding. Collecting cross slope data is typically only based on small sample because efficient technology and means to collect accurate cross slope data has been evasive. The advent of Light Detection and Ranging (LiDAR) scanning technology has proven to be a valuable tool in the creation of 3D terrain models. Combined with other technologies such as Global Positioning Systems (GPS) and Inertial Measurement Unit devices (IMU) it is now possible to collect accurate 3D coordinate data in the form of a …

First Principles-Based Microkinetic Modeling Of Ethanol From Syngas On Bimetallic Co-Pd Catalysts, Anuradha Gundamaraju

All Dissertations

In the future, the availability of reliable alternative fuels will be crucial for any country to become energy independent. One such alternative is ethanol as it can be used both as a fuel and as a fuel additive. Most of the ethanol produced in the world today is derived from biomass. The biomass feedstocks and fermentation broths used in ethanol production both contain high amounts of water and therefore, the energy efficiency of the process is lessened by product separation processes (azeotropic separation of water and ethanol) that are non-trivial and highly inefficient (due to the evaporation of water). An …

Particle Slip Velocity Influences Inertial Focusing Of Particles In Curved Microchannels, Saurabh Deshpande, Phanindra Tallapragada

Publications

Size based separation and identification of particles in microfluidics through purely hydrodynamic means has gained significant interest due to a number of possible biomedical applications. Curved micro-channels, particularly spiral micro-channels with rectangular cross-section and the dynamics of particles in such channels have been extensively researched to achieve size based separation of particles. In this paper we present evidence that sheds new light on the dynamics of particles in such curved channels; that a unique particle slip velocity is associated with the focusing positions in the cross sections, which leads to a balance of forces. Our experiments therefore imply that the …