Engineering Commons^™

Lateral Dynamics Of Multiple Trailer Trucks In Windy Environments, David Wafer

All Theses

The lateral response of three-trailer commercial vehicles has been assessed using the simulation package TruckSim^TM. Aerodynamic and mechanical characterizations for the vehicle were developed for this investigation. Simulations were carried out with various aerodynamic and load configurations with several different arbitrarily defined crosswinds. The aerodynamic configurations were tested in constant and random crosswinds. The load configurations were tested only in random crosswinds. Each aerodynamic configuration differed by the aerodynamic side-force coefficient for the trailers. Each load configuration consisted of reducing the payload in a single trailer. The tractor was identically defined for each load and aerodynamic configuration. Increasing …

Electric Power Synchrophasor Network Cyber Security Vulnerabilities, Christopher Beasley

All Theses

Smart grid technologies such as synchrophasor devices (Phasor Measurement Units (PMUs)), make real-time monitoring, control, and analysis of the electric power grid possible. PMUs measure voltage and current phasors across the electrical power grid, add a GPS time stamps to measurements, and sends reports to the Phasor Data Concentrators (PDCs) in the control centers. Reports are used to make decisions about the condition and state of the power grid. Since this approach relies on Internet Protocol (IP) network infrastructure, possible cybersecurity vulnerabilities have to be addressed to ensure that it is stable, secure, and reliable. In literature, attacks that are …

Preliminary Evaluation Of Kenaf As A Structural Material, Andrew Sheldon

All Theses

Kenaf (Hibiscus cannabinus L.) is an annual fiber plant that is kin to cotton and okra and native to east-central Africa, though it is currently grown in numerous locations around the globe. The plant's apparent high strength and light weight along with its environmental and sustainability advantages makes it a good candidate for use in structural materials. The goal of this study was to design a kenaf product that resembled parallel strand lumber and required minimal processing of the kenaf. The mechanical properties of the two main components of kenaf, the bast fibers and the core, were evaluated using experimental …

Gis-Based Suitability Modeling And Multi-Criteria Decision Analysis For Utility Scale Solar Plants In Four States In The Southeast Us, Kata Tisza

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Photovoltaic (PV) development shows significantly smaller growth in the Southeast U.S., than in the Southwest; which is mainly due to the low cost of fossil-fuel based energy production in the region and the lack of solar incentives. However, the Southeast has appropriate insolation conditions (4.0-6.0 KWh/m2/day) for photovoltaic deployment and in the past decade the region has experienced the highest population growth for the entire country. These factors, combined with new renewable energy portfolio policies, could create an opportunity for PV to provide some of the energy that will be required to sustain this growth. The goal of the study …

Inverse Problems Using Reduced Basis Method, Phil Gralla

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Inverse Problems is a field of great interest for many applications, such as parameter identification and image reconstruction. The underlying models of inverse problems in many applications often involve Partial Differential Equations (PDEs). A Reduced Basis (RB) method for solving PDE based inverse problems is introduced in this thesis. The RB has been rigorously established as an efficient approach for solving PDEs in recent years. In this work, we investigate whether the RB method can be used as a regularization for solving ill-posed and nonlinear inverse problems using iterative methods. We rigorously analyze the RB method and prove convergence of …

Design Of A High Temperature Subsurface Thermal Energy Storage System, Qi Zheng

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Solar thermal energy is taking up increasing proportions of future power generation worldwide. Thermal energy storage technology is a key method for compensating for the inherent intermittency of solar resources and solving the time mismatch between solar energy supply and electricity demand. However, there is currently no cost-effective high-capacity compact storage technology available (Bakker et al., 2008). The goal of this work is to propose a high temperature subsurface thermal energy storage (HSTES) technology and demonstrate its potential energy storage capability by developing a solar-HSTES-electricity generation system. In this work, main elements of the proposed system and their related state-of-art …

Emc In Power Electronics And Pcb Design, Chentian Zhu

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This dissertation consists of two parts. Part I is about Electromagnetic Compatibility (EMC) in power electronics and part II is about the Maximum Radiated Electromagnetic Emissions Calculator (MREMC), which is a software tool for EMC in printed circuit board (PCB) design. Switched-mode power converters can be significant sources of electromagnetic fields that interfere with the proper operation of nearby circuits or distant radio receivers. Part I of this dissertation provides comprehensive and organized information on the latest EMC developments in power converters. It describes and evaluates different technologies to ensure that power converters meet electromagnetic compatibility requirements. Chapters 2 and …

A Study Of The Effects Of Manufacturing Complexity On Product Quality In Mixed-Model Automotive Assembly, Kavit Ravindra Antani

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The objective of this research is to test the hypothesis that manufacturing complexity can reliably predict product quality in mixed-model automotive assembly.

Originally, assembly lines were developed for cost efficient mass-production of standardized products. Today, in order to respond to diversified customer needs, companies have to allow for an individualization of their products, leading to the development of the Flexible Manufacturing Systems (FMS). Assembly line balancing problems (ALBP) consist of assigning the total workload for manufacturing a product to stations of an assembly line as typically applied in the automotive industry. Precedence relationships among tasks are required to conduct partly …

Evaluation Of Turbidity Reduction Using Polyacrylamide With Linear Sediment Control Best Management Practices, Jacob O. Burkey

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Accelerated erosion and highly turbid stormwater runoff from construction sites are known to cause a variety of environmental and economic problems. To reduce turbidity and keep eroded sediment on site, this research was conducted to evaluate the potential for turbidity reduction using polyacrylamide (PAM) flocculants with sediment control best management practices (BMPs).

Previous research has shown significant turbidity reduction when applying granular PAM to linear sediment control BMPs. Numerous studies indicate that PAM loses efficacy if it becomes wet and then dries. This makes PAM reapplication a necessary part of maintaining sediment control BMPs using PAM and suggests that further …

Developing A South Carolina Traffic Incident Management Plan Along The I-26 Corridor Between Columbia And Charleston, Laura Rowe

All Theses

Traffic Incident Management (TIM) programs are used in many states across the nation to efficiently clear interstate incidents and alleviate congestion in response to incidents. The overarching goal of this research is to maintain safety of the motoring public and incident responders while reducing congestion, secondary collisions, and traffic delays from incidents that occur on South Carolina highways. To reduce incident clearance times along the I-26 corridor between Columbia and Charleston through the implementation of a Traffic Incident Management (TIM) Program, several objectives for this thesis were established to move toward the goal, including; defining gaps between national TIM best-practices …

Improved Mixed-Integer Models Of A Two-Dimensional Cutting Stock Problem, William Lassiter

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This paper is concerned with a family of two-dimensional cutting stock problems that seeks to cut rectangular regions from a finite collection of sheets in such a manner that the minimum number of sheets is used. A fixed number of rectangles are to be cut, with each rectangle having a known length and width. All sheets are rectangular, and have the same dimension. We review two known mixed-integer mathematical formulations, and then provide new representations that both economize on the number of discrete variables and tighten the continuous relaxations. A key consideration that arises repeatedly in all models is the …

Monitoring Hospital Safety Climate Using Control Charts Of Non-Harm Events In Reporting Systems, Susan Robinson

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The primary aim of this thesis is to design an approach and demonstrate a methodology to supplement safety culture assessment efforts. The framework affords an enhanced understanding of hospital safety climate, specifically reporting culture, through the use of control charts to monitor non-harm patient safety events documented in reporting systems. Assessing safety culture and climate remains difficult. One of the most common methods to assess safety culture is a self-report survey administered annually. Surveys assess safety climate, because they are a snapshot of the management's and front-line staff's perceptions of safety within their settings. One component of safety culture is …

Privacy Preserving Statistics, Oluwakemi Hambolu

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Over the past few years, there have been an increase in the development and improvement of circumvention tools like Tor and Psiphon. These tools provide an environment for citizens of oppressive regimes to access websites freely without fear of identification, these tools aid democracy activists and journalists in West Africa in using the Internet securely. A similar circumvention tool was developed by us. This tool circumvents DNS and IP address blocking/filtering, by leveraging technologies developed by criminal botnet enterprises. To improve and maintain the circumvention tool we developed, it is important to quantify the number and country of origin of …

Density Functional Theory Study Of The Thermodynamics Of Catalytic Remediation Of Nitrate In Water, Lizzie Bollmann

All Theses

Over 1 billion people worldwide lack access to safe drinking water and 5,000 people die each day due to drinking contaminated water. With the development of new industries, new substances and chemicals are entering the waters every day, and the current water treatment processes are unable to remove them entirely. For example, agriculture is the world's heaviest consumer of water, and nitrates and nitrites from fertilizers are washed away with the water to rivers and streams. These chemicals can cause problems to humans and to the environment. To humans, they can cause methemoglobinemia, also known as 'blue baby syndrome'. To …

Comparison Of The Design-Bid-Build And Construction Manager At Risk Project Delivery Methods Utilized For The Construction Of Public Schools, Noel Carpenter

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Clemson University Science Master's Program In Sustainable And Resilient Infrastructure: A Program Evaluation, Elizabeth O'Sell

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The Clemson University Science Master's Program (SMP) in Sustainable and Resilient Infrastructure is a program which aims to link engineering, materials, construction, environment, architecture, business, and public policy to produce graduates with unique holistic perspective and expertise to immediately contribute to the workforce in the area of sustainable and resilient infrastructure. A program evaluation of the SMP has been performed to study the effectiveness of the SMP and identify areas where the goals and vision of the SMP are achieved and areas where improvements can be made. This was completed by analysis of trends within survey responses, review of Master's …

Analysis And Mitigation Of Impacts Of Plug-In Electric Vehicles On Distribution System During Faults, Himanshu Bihani

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With rising concerns for environment, energy security and gasoline prices, penetration of plug-in electric vehicles (PEV) is bound to increase in the distribution system. The load characteristics of the distribution system with PEVs will be considerably different and hence its effects on the system needs to evaluated. Determination of the characteristics of the impacts will help utilities to prepare methodologies in advance to accommodate this new kind of load. Batteries of most of these vehicles will be charged using a single phase power electronic chargers. To study impact of these chargers on distribution system during fault and fault recovery is …

Adsorption Of Synthetic Organic Chemicals: A Comparison Of Superfine Powdered Activated Carbon With Powdered Activated Carbon, Semra Bakkaloglu

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In literature, manufacturer-supplied powdered activated carbon has been ground to produce submicron particles with mean diameter lower than 1µm for use as an adsorbent during water treatment. Superfine powdered activated carbon (SPAC) can be used for removal of natural organic matter as well as synthetic organic chemicals (SOCs) from water. It has been suggested that SPAC has higher adsorption capacity than powdered activated carbon (PAC) due to larger external surface area and mesopore volume. Another advantage of SPAC over PAC is the faster uptake rate for both NOM and SOC during adsorption owing to small particle size. Therefore, understanding SPAC …

The Effect Of Decorative Foil Stamping On Consumer Attention, Julianne Holmes

All Theses

Packaging plays a key role in communicating product benefits to consumers at the point of sale (Rundh, 2009). Oftentimes, designers use high visibility enhancements to help the package stand out among competitors. Although luxury products often use high-end graphic techniques to convey high quality product, many private label package designers are also using these enhancements to attract attention to their products. Foil stamping is a high visibility enhancement that can create a rich and elegant effect on a package. The process involves transferring a thin layer of foil onto a substrate by using pressure and heat. No quantitative research has …

A Comparative Study: Structural Complexity Metrics Applied Against Function And Assembly Product Graphs In Predicting Market Price And Assembly Time, Sri Ram Mohinder Cherkadu Vasala

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The overarching objective of this research is to investigate the measurement and use of complexity in the prediction of product performance metrics (assembly time and market cost) for two model graph types (assembly models and function structures). This research focusses on analyzing how accurate the prediction of performance metrics are based on these graph types. This research focuses on developing four prediction models: Function Structures to predict Market Price (FS-MP), Assembly Models to predict Assembly Time (AM-AT), Function Structures to predict Assembly Time (FS-AT), and Assembly Models to predict Market Price (AM-MP). These assembly models and function structures are analyzed …

Design And Implementation Of A Real-Time Adaptive Oxygen Transfer Rate Estimator, Li Wang

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Oxygen transfer rate (OTR) is the most signicant signal for aerobic bioprocess control, since most microbic metabolic activity relies on oxygen consumption. However, accurate estimation of OTR is challenging due to the difficulty of determining uncertain oxygen transfer parameters and system dynamics. This paper presents an adaptive estimator, which incorporates exhaust gas, stir speed and dissolved oxygen measurements, to predict the real-time OTR. The design of this estimator takes into account the headspace dilution effect, off-gas sensor dynamics and uncertain oxygen transfer parameters. Accurate and real-time OTR signal is derived by combining the low latency property of stir speed and …

Identifying Target Properties For The Design Of Meta-Material Tank Track Pads, Venkata Sampath Dangeti

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On track vehicle systems, track pads are designed to provide traction and support the weight of the vehicle, they have limited service life due to common failure by blowout. According to the literature, blowout is a failure mode caused by overheating due to hysteresis in elastomeric materials during high speed operations. Elastomers are used primarily for their high compliance, which is essential to protect the suspension components and maintain structural integrity of the track pad. The objective of the work is to explore the use of linear elastic meta-materials with optimized topology to replace elastomers and reduce or eliminate the …

Biomass And Lipid Production Of Chlorella Protothecoides Under Heterotrophic Cultivation On A Mixed Waste Substrate Of Brewer Fermentation And Crude Glycerol, Xiaoyu Feng

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Biodiesel production using Chlorella protothecoides microalgae species has become an attractive topic due to the intense requirements of renewable energy in past decades. While, the expensive capital cost of the carbon and nitrogen substrates for algae growth is becoming a restrictive problem in this filed. In this study, heterotrophic cultivation of Chlorella protothecoides in the dark was conducted in 500mL shake flasks. Chlorella protothecoides growth in mixed substrate of brewer fermentation and biodiesel crude glycerol by-products containing a relatively high concentration of carbon and nitrogen was discussed and compared with that in microalgae basal medium which was supplied with 30 …

Design Of A Custom Software Application To Monitor And Communicate Cnc Machining Process Information To Aid In Chatter Identification, Valerie Pezzullo

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In any manufacturing environment, it is important to be able to monitor the Computer Numerical Control (CNC) machining process so that high quality parts can be produced in the least amount of time in order to be profitable. This involves acquiring the proper parameters needed from the machine's controller, which can prove to be difficult with proprietary machine tools that tend to limit access to the internal data collected by the controller. This closed approach to controller design also means that many technological advances that have recently become prevalent in society are not being adopted in the manufacturing industry, preventing …

Ultra-Wideband Position Tracking On An Assembly Line, Harikrishnan Ravikrishnan

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This works considers the problem of tracking objects on an assembly line using an ultra-wideband (UWB) positioning system. Assembly line tracking can be accomplished using touch sensors that physically detect when an object reaches a given location. Such tracking requires sensors placed throughout the entire assembly line, and only provides readings at the sensor locations. In contrast, UWB position tracking utilizes a set of sensors surrounding the whole area, enabling continuous position tracking with less infrastructure. Similar tracking can be accomplished using radio frequency identication (RFID) sensing, but this only provides readings when the parts are near RFID readers. The …

Post-Tensioning To Prevent End-Region Cracks In Pretensioned Concrete Girders, Michael Willis

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Web-splitting cracking during and immediately after prestress transfer is a common problem in pretensioned concrete beams, often with lasting effects on the durability and performance. By providing an entry point for chlorides and other corrosives, end-region cracks enable degradation of reinforcing steel and further cracking. Current practices offer a variety of methods for controlling end-region cracking. However, methods for preventing--not just controlling or repairing--end-region cracks are necessary to improve prestressed concrete construction. Vertical end-region post-tensioning is a developing method for preventing web-splitting cracks. The purpose of this document is to explore implementation methods of post-tensioning using the turn-of-the nut procedure, …

Ear Contour Detection And Modeling Using Statistical Shape Models, Satish Ravindran

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Ear detection is an actively growing area of research because of its applications in human head tracking and biometric recognition. In head tracking, it is used to augment face detectors and to perform pose estimation. In biometric systems, it is used both as an independent modality and in multi-modal biometric recognition. The ear shape is the preferred feature used to perform detection because of its unique structure in both 2D color images and 3D range images. Ear shape models have also been used in literature to perform ear detection, but at a cost of a loss in information about the …

Influence Of Different Rubber Modified Binder Variables On Performance Properties Of Porous Asphalt Mixtures, Katelyn Love

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Porous asphalt is a type of pavement in which surface water can permeate down into the subbase below. Open graded friction course (OGFC) is a type of porous asphalt often used as a surface course on top of dense graded pavements on high speed roadways. Due to an increase in waste tires, rubber modified asphalt has become an increasingly popular material around the world, including the US. The rubber modified asphalt is created by utilizing processed rubber particles blended into the mixture. This research investigated the effects of rubber modified binder on the performance of porous asphalt by evaluating the …

Vascular Nanomedicine: Site Specific Delivery Of Elastin Stabilizing Therapeutics To Damaged Arteries, Aditi Sinha

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Elastin, a structural protein in the extra-cellular matrix, plays a critical role in the normal functioning of blood vessels. Apart from performing its primary function of providing resilience to arteries, it also plays major role in regulating cell-cell and cell-matrix interactions, response to injury, and morphogenesis. Medial arterial calcification (MAC) and abdominal aortic aneurysm (AAA) are two diseases where the structural and functional integrity of elastin is severely compromised. Although the clinical presentation of MAC and AAA differ, they have one common underlying causative mechanism--pathological degradation of elastin. Hence prevention of elastin degradation in the early stages of MAC and …

Uv-Assisted Stabilization Of Polyacrylonitrile-Based Carbon Fiber Precursors, Marlon Salvador Morales Sandoval

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Due to their high strength and stiffness coupled with low density, carbon fibers are the preferred reinforcing fibers used in high-performance polymer matrix composites. Consequently, the demand for carbon fibers is expected to grow from 40,000 metric tons to about 150,000 metric tons over the next decade. A large fraction of the increase is anticipated in the industrial sector that is cost-sensitive. Therefore, there is a need for the development of novel processes and precursors to reduce the carbon fiber production cost and expand the use of carbon fibers. This research focuses on the development of an alternative, rapid stabilization …