Open Access. Powered by Scholars. Published by Universities.®

Engineering Commons™

Open Access. Powered by Scholars. Published by Universities.®

Clemson University

Discipline
Keyword
Publication Year
Publication
Publication Type
File Type

Articles 1051 - 1080 of 2584

Full-Text Articles in Engineering

Shrinkage Analysis Of Carbon Micro Structures Derived From Su-8 Photoresist, Rucha Natu, Monsur Islam, Rodrigo Martinez-Duarte May 2016

Shrinkage Analysis Of Carbon Micro Structures Derived From Su-8 Photoresist, Rucha Natu, Monsur Islam, Rodrigo Martinez-Duarte

Publications

We present preliminary results for the analysis of shrinkage of 3D carbon posts obtained by the pyrolysis of SU-8 precursor structures, in a technique known as Carbon MEMS. Though the shrinkage in the carbon structures is highly reproducible, there is a strong dependence of this shrinkage on the initial dimensions of the SU-8 pillars. Our hypothesis is that the shrinkage depends upon the area available for degassing during carbonization. In this work, this idea is used to analyze shrinkage in cylindrical pillars. The results obtained are studied based on the ratio of lateral and top surface area available for degassing …


Analysis Of Large Scale Pv Systems With Energy Storage To A Utility Grid, Joseph M. Lavalliere May 2016

Analysis Of Large Scale Pv Systems With Energy Storage To A Utility Grid, Joseph M. Lavalliere

All Theses

With electric distribution network operators experiencing an exponential increase in distributed energy resource connections to the power grid, operational challenges arise attributable to the traditional methods of building distribution feeders. Photovoltaic (PV) solar systems are the major contributor due to recent technological advancements. Though this renewable energy resource is beneficial to human society, unfavorable electrical conditions can arise from the inherit variability of solar energy. Extreme variability of power injection can force excessive operations of voltage regulation equipment and potentially degrade customer voltage quality. If managed and controlled properly, battery energy storage systems installed on a distribution feeder have the …


Fabrication And Characterization Of An Extracellular Matrix Hydrogel For Aortic Valve Applications, Brady Culbreth May 2016

Fabrication And Characterization Of An Extracellular Matrix Hydrogel For Aortic Valve Applications, Brady Culbreth

All Theses

With an estimated 5 million people suffering from valve disease in the United, valve disease is currently the leading cause of cardiovascular disease. Each year, between 80,000 and 85,000 aortic valve replacements are performed in order to treat the stenotic heart valves. Despite this being a worldwide epidemic, the current valve replacement options that are on the market have distinct limitations. Furthermore, a viable alternative does not exist for the patients that are not candidates for the current treatment methods. Our proposed solution to this epidemic is to create a highly viable injectable scaffold that would allow for the minimally …


Design Of A Wide Area Controller Using Eigenstructure Assignment In Power Systems, Parimal Saraf May 2016

Design Of A Wide Area Controller Using Eigenstructure Assignment In Power Systems, Parimal Saraf

All Dissertations

Small signal stability has become a major concern for power system operators around the world. This has resulted from constantly evolving changes in the power system ranging from increased number of interconnections to ever increasing demand of power. In highly stressed operating conditions, even a small disturbance such as a load change can make the system unstable resulting in small signal instability. The main reason for small signal instability in power systems is an inter-area mode/s becoming unstable. Inter-area modes involve a group of generators oscillating against each other. Traditionally, power system stabilizers installed on the synchrous machines were used …


Low Cost, Carbon-Based Micro- And Nano-Structured Electrodes For High Performance Supercapacitors, Kryssia Pamela Díaz Orellana May 2016

Low Cost, Carbon-Based Micro- And Nano-Structured Electrodes For High Performance Supercapacitors, Kryssia Pamela Díaz Orellana

All Dissertations

Advances in the development of sustainable, low-cost, and reliable energy storage technologies have become a high priority as the demand for high power, and high energy storage devices has risen with emerging technologies in electronics, transportation, and renewable energy systems. Supercapacitors, due to their relatively high energy density and power density, provide an attractive alternative to bridge the gap between conventional batteries and capacitors. Materials ranging from high surface area, inert carbons to Faradaic metal oxides and conducting polymers have been used to achieve a range of performance properties in supercapacitors. However, the development of new technologies faces many challenges, …


The Professional Constructor, Full Issue, Volume 40, Number 01 Apr 2016

The Professional Constructor, Full Issue, Volume 40, Number 01

The Professional Constructor

No abstract provided.


Spring 2016 - Volume 40, Number 1, Full Issue Mar 2016

Spring 2016 - Volume 40, Number 1, Full Issue

The Professional Constructor

No abstract provided.


Strategies For Reducing The Environmental Impacts Of Construction, Jordan Moran Mar 2016

Strategies For Reducing The Environmental Impacts Of Construction, Jordan Moran

The Professional Constructor

Sustainable building is a complex goal to reach even for the most seasoned project managers. If theyfocus on the ideas to reduce, reuse, and recycle that goal becomes much more obtainable. The project manager mustset his expectations and priorities from the moment the contract is signed to navigate which routes are most possible toachieve given the project scope and delivery method. The key to success is to relay the long term benefits of sustainablebuilding on to the owner, and make them realize that up-front cost should take a back seat to life cycle. This will save theenvironment and the owner’s …


General Interest Articles, The Professional Constructor Mar 2016

General Interest Articles, The Professional Constructor

The Professional Constructor

No abstract provided.


Contractor Feasibility In Providing Cost Segregation Studies From Detailed Estimates: A Case Study, Ben F. Bigelow, Jeremy Robinson, John Killingsworth Mar 2016

Contractor Feasibility In Providing Cost Segregation Studies From Detailed Estimates: A Case Study, Ben F. Bigelow, Jeremy Robinson, John Killingsworth

The Professional Constructor

Profit margins are tight for general contractors, averaging under 3% (Construction Financial Management Association). Further, competition for projects can be very fierce, so any opportunity for increased profit or a competitive advantage in bidding bears consideration by general contractors. Cost segregation studies represent such an opportunity but the feasibility of a general contractor providing them has not been studied. A cost segregation study allows a property owner to accelerate the depreciation of certain portions of a building thus reducing tax liability and increasing cash flow. Because the information needed for a cost segregation study can be found in a detailed …


A Framework For Analyzing Intraorganizational Congruence Of Safety Practices On Safety Performance – A Pilot Study Of Construction, Benjamin Hill, Mohammed S. Hashem M. Mehany, Richard J. Gebken Mar 2016

A Framework For Analyzing Intraorganizational Congruence Of Safety Practices On Safety Performance – A Pilot Study Of Construction, Benjamin Hill, Mohammed S. Hashem M. Mehany, Richard J. Gebken

The Professional Constructor

Previous research has determined that improving employee congruence on organizational methods and goals leads to improved organizational performance. This research establishes a comprehensive framework of common and recommended safety practices that can be used for intraorganizational congruence data collection regarding safety practices. The research is also developing a method for congruence calculation and examine the congruence effect on the subcontractor’s safety performance metrics through a pilot study. The established framework identified and organized 170 practices under seven conceptual, safety-practice categories. The congruence analysis and the pilot study revealed several areas of high and low congruency along with significant correlations between …


Factors Of Employee Loyalty Among Construction Management Field Personnel, Estimators & Bim/Design Specialists: Insights For General Contractors, Colby Humphrey, Ben F. Bigelow Mar 2016

Factors Of Employee Loyalty Among Construction Management Field Personnel, Estimators & Bim/Design Specialists: Insights For General Contractors, Colby Humphrey, Ben F. Bigelow

The Professional Constructor

Since 2008 construction employment has dropped considerably and has remained below 2007 levels, with construction management positions still about 14% down (U.S. Department of Labor 2015). Despite the boom currently occurring in the construction industry, general contractors (GCs) are finding it difficult to fill project management positions (AGC 2014), and construction firms expect these challenges to continue (Mutikani 2014). With greater demand for managers, retaining quality people is a paramount concern. Everyone knows the adage that “money talks”, but what can a GC do to engender loyalty besides just paying more? To explore that question and attempt to better understand …


Construction Industry Professionals Perception Of Project Management Certification In The Houston Texas Region, Lana K. Coble, Margaret D. Watson Mar 2016

Construction Industry Professionals Perception Of Project Management Certification In The Houston Texas Region, Lana K. Coble, Margaret D. Watson

The Professional Constructor

Individual construction design professionals are evaluated on their abilities by state licensing boards in all 50 states of North America. The construction industry has relied upon construction company licenses in 42% of the United States to ensure that buildings are constructed to local area codes. Current practices have created a credibility gap when comparing construction managers to design professionals. Only since the 1970s, have third party agencies led an effort to provide construction management professionals with a certification to establish baseline competencies. To date, research on construction manager certification has been minimal; therefore, this research attempts to contribute to needed …


Measuring Organizational Learning Success In Commercial Construction During Economic Recession, Evan Danforth, Justin Weidman, Clifton Farnsworth Mar 2016

Measuring Organizational Learning Success In Commercial Construction During Economic Recession, Evan Danforth, Justin Weidman, Clifton Farnsworth

The Professional Constructor

The method through which organizations collect and internalize knowledge, termed organizational learning, has been theorized to significantly influence company performance. Specifically, the speed and accuracy of knowledge transfer boasted by organizational learning proponents is thought to assist companies in dealing with, and even benefiting from, environmental changes such as economic volatility. This research studied the organizational learning of fifteen commercial construction companies in the southwestern United States during the 2008-2009 U.S. recession through semi-structured interviews. It was found that the companies that exhibited dramatically higher or lower levels of organizational learning generally experienced correspondingly higher or lower performance. The contribution …


Strategies For Reducing The Environmental Impacts Of Construction “Improving Erosion And Sedimentation Control Practices On Construction Projects”, Richard Pate Jr Mar 2016

Strategies For Reducing The Environmental Impacts Of Construction “Improving Erosion And Sedimentation Control Practices On Construction Projects”, Richard Pate Jr

The Professional Constructor

There are numerous potential impacts associated with constructing our built environment; one in particular is fresh on contractor’s minds around the country and that is the erosion and sedimentation of our waterways. In this essay, I explain why this issue has become such a pivotal discussion within construction and green building efforts, what strategies have recently become available for addressing these issues, and how their implementation will affect a project’s overall budget and schedule. The strategies I have chosen to discuss are silt fence tieback systems, polyacrylamide (PAM) flocculants, and unmanned aerial vehicle inspections.


Strategies For Reducing The Environmental Impacts Of Construction, Alex Stewar Mar 2016

Strategies For Reducing The Environmental Impacts Of Construction, Alex Stewar

The Professional Constructor

In order to carry out a successful and sustainable construction project, quality project planning isessential. In this paper, I will discuss how design and preconstruction are the most important parts of a sustainableconstruction project. The three main points will be about the importance of selling sustainability to the owner, choosingthe proper project delivery method to integrate team members, and planning for the future when designing the project.Finally, I will touch on how my own education through the Construction Science and Management program at ClemsonUniversity has prepared me for this new era of construction.


Synchronization Of Pulse-Coupled Oscillators To A Global Pacemaker, Felipe Nunez, Yongqiang Wang, Andrew R. Teel, Francis J. Doyle Iii Feb 2016

Synchronization Of Pulse-Coupled Oscillators To A Global Pacemaker, Felipe Nunez, Yongqiang Wang, Andrew R. Teel, Francis J. Doyle Iii

Publications

Pulse-coupled oscillators (PCOs) are limit cycle oscillators coupled by exchanging pulses at discrete time instants. Their importance in biology and engineering has motivated numerous studies aiming to understand the basic synchronization properties of a network of PCOs. In this work, we study synchronization of PCOs subject to a global pacemaker (or global cue) and local interactions between slave oscillators. We characterize solutions and give synchronization conditions using the phase response curve (PRC) as the design element, which is restricted to be of the delay type in the first half of the cycle, interval (0,π)(0,π), and of the advance type in …


A Multi-Objective, Hub-And-Spoke Model To Design And Manage Biofuel Supply Chains, Mohammad S. Roni, Sandra D. Eksioglu, Kara G. Cafferty, Jacob J. Jacobson Jan 2016

A Multi-Objective, Hub-And-Spoke Model To Design And Manage Biofuel Supply Chains, Mohammad S. Roni, Sandra D. Eksioglu, Kara G. Cafferty, Jacob J. Jacobson

Publications

In this paper we propose a multi-objective, mixed integer linear programming model to design and manage the supply chain for biofuels. This model captures the trade-offs that exist between costs, environmental and social impacts of delivering biofuels. The in-bound supply chain for biofuel plants relies on a hub-and-spoke structure which optimizes transportation costs of biomass. The model proposed optimizes the CO2" style="position: relative;" tabindex="0" id="MathJax-Element-1-Frame">CO2 emissions due to transportation-related activities in the supply chain. The model also optimizes the social impact of biofuels. The social impacts are evaluated by the number of jobs created. The multi-objective optimization model is …


Optimization Models To Integrate Production And Transportation Planning For Biomass Co-Firing In Coal-Fired Power Plants, Sandra D. Eksioglu, Hadi Karimi, Burak Eksioglu Jan 2016

Optimization Models To Integrate Production And Transportation Planning For Biomass Co-Firing In Coal-Fired Power Plants, Sandra D. Eksioglu, Hadi Karimi, Burak Eksioglu

Publications

Co-firing biomass is a strategy that leads to reduced greenhouse gas emissions in coal-fired power plants. Incentives such as production tax credit (PTC) are designed to help power plants overcome the financial challenges faced during the implementation phase. Decision makers at power plants face two big challenges. The first challenge is identifying whether the benefits from incentives such as PTC can overcome the costs associated with co-firing. The second challenge is identifying the extent to which a plant should co-fire in order to maximize profits. We present a novel mathematical model that integrates production and transportation decisions at power plants. …


Fully Magnetic Printing By Generation Of Magnetic Droplets On Demand With A Coilgun, Vladislav Vekselman, Luke Sande, Konstantin G. Kornev Dec 2015

Fully Magnetic Printing By Generation Of Magnetic Droplets On Demand With A Coilgun, Vladislav Vekselman, Luke Sande, Konstantin G. Kornev

Publications

In this paper, we exhibit a coilgun-based approach to drop-on-demand printing of liquids laden with magnetic particles. In contrast to other drop-on-demand technologies designed to print droplets only in gaseous environments, this methodology allows one to print magnetic droplets inside any gaseous or liquid media using the same coilgun. Furthermore, we demonstrate the basic principles of magnetic drop-on-demand generation and show the physico-chemical parameters controlling the process.


Design Of A Meta-Material With Targeted Nonlinear Deformation Response, Zachary Satterfield Dec 2015

Design Of A Meta-Material With Targeted Nonlinear Deformation Response, Zachary Satterfield

All Theses

The M1 Abrams tank contains track pads consist of a high density rubber. This rubber fails prematurely due to heat buildup caused by the hysteretic nature of elastomers. It is therefore desired to replace this elastomer by a meta-material that has equivalent nonlinear deformation characteristics without this primary failure mode. A meta-material is an artificial material in the form of a periodic structure that exhibits behavior that differs from its constitutive material. After a thorough literature review, topology optimization was found as the only method used to design meta-materials. Further investigation determined topology optimization as an infeasible method to design …


An Examination Of Microbial Community Composition At Tba-Degrading Versus Non-Degrading Sites, Courtney Thompson Dec 2015

An Examination Of Microbial Community Composition At Tba-Degrading Versus Non-Degrading Sites, Courtney Thompson

All Theses

Understanding how fuel oxygenates interact with microorganisms in the subsurface is important for the remediation of contaminated sites and designing and optimizing remedial strategies. The current understanding of methyl tertiary butyl ether (MTBE) and tertiary butyl alcohol (TBA) degradation in the environment has been developed primarily through gas chromatography GC analysis and culture-based laboratory studies. Microbial communities can be very diverse, and while microcosm studies provide valuable data, few metagenomic studies have been performed. To elucidate the significant microorganisms and pathways involved in the breakdown of MTBE and TBA, the compositions of entire indigenous microbial populations must be investigated and …


Experimental Investigation Of Heat Leakage And Air Leakage In Domestic Refrigerators, Shervin Shoai Naini Dec 2015

Experimental Investigation Of Heat Leakage And Air Leakage In Domestic Refrigerators, Shervin Shoai Naini

All Theses

The optimization of the energy consumption in household refrigerators should consider the influence of the gasket which determines the heat transfer and air infiltration rate. In this research project, engineering methods are developed to evaluate the heat leakage due to the gasket and air infiltration in domestic refrigerators. In the first study, experimental and numerical approaches are applied to evaluate the gasket heat transfer based on the “Reverse Heat Load Method”. The main objective is to find the effective heat leakage with the dimensions of energy leakage per gasket length per temperature difference (W/m.K). An insulated cubic box with a …


Parking Lot Monitoring System Using An Autonomous Quadrotor Uav, Venkataraman Ganesh Dec 2015

Parking Lot Monitoring System Using An Autonomous Quadrotor Uav, Venkataraman Ganesh

All Theses

The main goal of this thesis is to develop a drone-based parking lot monitoring system using low-cost hardware and open-source software. Similar to wall-mounted surveillance cameras, a drone-based system can monitor parking lots without affecting the flow of traffic while also offering the mobility of patrol vehicles. The Parrot AR Drone 2.0 is the quadrotor drone used in this work due to its modularity and cost efficiency. Video and navigation data (including GPS) are communicated to a host computer using a Wi-Fi connection. The host computer analyzes navigation data using a custom flight control loop to determine control commands to …


A Study On General Assembly Line Balancing Modeling Methods And Techniques, Bryan Pearce Dec 2015

A Study On General Assembly Line Balancing Modeling Methods And Techniques, Bryan Pearce

All Dissertations

The borders of the assembly line balancing problem, as classically drawn, are as clear as any other operations research topic in production planning, with well-defined sets of assumptions, parameters, and objective functions. In application, however, these borders are frequently transgressed. Many of these deviations are internal to the assembly line balancing problem itself, arising from any of a wide array of physical or technological features in modern assembly lines. Other issues are founded in the tight coupling of assembly line balancing with external production planning and management problems, as assembly lines are at the intersection of multiple related problems in …


Improving The Implementation Of Pavement Preservation Strategies In South Carolina, Franklin Reed Dec 2015

Improving The Implementation Of Pavement Preservation Strategies In South Carolina, Franklin Reed

All Theses

With compounding budget constraints on infrastructure, cost effective solutions to maintain roadways are becoming increasingly important. Pavement preservation provides a cost effective option to keep the roadway network at an acceptable level. However, pavement preservation is a relatively new concept that many states have not fully implemented successfully. This research supports efforts to improve the pavement preservation practices in the state of South Carolina. It analyzes the current pavement preservation practices in South Carolina as well as other states to identify where improvements could be made. The research also outlines a treatment tracking program for the state of South Carolina …


Co-Design Of Dynamic Real-Time Scheduling And Cooperative Control For Human-Agent Collaboration Systems Based On Mutual Trust, Xiaotian Wang Dec 2015

Co-Design Of Dynamic Real-Time Scheduling And Cooperative Control For Human-Agent Collaboration Systems Based On Mutual Trust, Xiaotian Wang

All Theses

Mutual trust is a key factor in human-human collaboration. Inspired by this social interaction, we analyze human-agent mutual trust in the collaboration of one human and (semi)autonomous multi-agent systems. In the thesis, we derive time-series human-agent mutual trust models based on results from human factors engineering. To avoid both over- trust and under-trust, we set up dynamic timing models for the multi-agent scheduling problem and develop necessary and sufficient conditions to test the schedulability of the human multi-agent collaborative task. Furthermore, we extend the collaboration between one human and multiple agents into the collaboration between multi-human network and swarm-based agents …


A Robust Data Exchange Framework For Connected Vehicle Technology Supported Dynamic Transit Operations, Yucheng An Dec 2015

A Robust Data Exchange Framework For Connected Vehicle Technology Supported Dynamic Transit Operations, Yucheng An

All Theses

Transit systems are an integral part of surface transportation systems. A connected vehicle technology (CVT) supported transit system will assist the users to manage trips both dynamically and efficiently. The primary focus of this research is to develop and evaluate the performance of a secure, scalable, and resilient data exchange framework. In the developed data exchange framework, a new data analytics layer, named Transit Cloud, is used to receive data from different sources, and send it to different users for a Dynamic Transit Operations (DTO) application. The DTO application allows the transit users to request trip information and obtain itineraries, …


Decellularized Bovine Nucleus Pulposus As A Biomimetic Scaffold For Intervertebral Disc Regeneration, Christopher Fernandez Dec 2015

Decellularized Bovine Nucleus Pulposus As A Biomimetic Scaffold For Intervertebral Disc Regeneration, Christopher Fernandez

All Theses

Low back pain (LBP) is a significant burden with a lifetime prevalence of 84% and estimated expenditures of $85.9 billion.[1,2] Although LBP is multifactorial; it has been shown that LBP can originate from degenerating intervertebral discs (IVDs); a process which initiates in the nucleus pulposus (NP); a hydrated tissue primarily composed of type 2 collagen and proteoglycan. Current therapies for IVD degeneration (IDD) are palliative and merely delay surgical management. While these procedures may relieve pain temporarily, they fail to address the underlying cause of degeneration and make no attempt to regenerate the effected tissue. Additional concerns with the use …


Electrical Characterization Of Gold And Platinum Thin Film Electrodes With Polyaniline Modified Surfaces, John Aggas Dec 2015

Electrical Characterization Of Gold And Platinum Thin Film Electrodes With Polyaniline Modified Surfaces, John Aggas

All Theses

Recent studies into soft organic electronics have burgeoned as a result of discoveries of conducting polymers such as polyaniline, polythiophene, and polypyrrole. However, in order to make these conducting polymers suitable for in vivo soft organic electronics, they must be developed so that they can be biocompatible and provide accurate sensing. Chitosan, a naturally occurring polymer structure found in exoskeletons of crustaceans, has been studied for its biocompatible properties. Composites of polyaniline (PAn), an intrinsically conductive polymer (ICP) and chitosan (Chi), a biopolymer, were developed and applied to gold and platinum Thin Film Electrode (TFE) devices. Electropolymerization and drop cast …