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Full-Text Articles in Engineering

The Evaluation Of Ensemble Sentiment Classification Approach On Airline Services Using Twitter, Zechen Wang Jan 2017

The Evaluation Of Ensemble Sentiment Classification Approach On Airline Services Using Twitter, Zechen Wang

Dissertations

In the field of sentiment classification, much research has been done on reviews of topics such as movies, software and books. Little research has been done in the airline service domain. In the airline industry, the use of social media as a customer service tool has become a growing phenomenon. The research conducted by Wan and Gao (2015) has proposed an ensemble classification approach for airline service sentiment classification using Twitter data. In accordance, the objective of improving the performance of ensemble classification approach is the primary consideration. This research proposed new hybrid classification approach that uses the state-of-art approach …


Development Of Standard Operating Procedure: Admicellar Polymerization Of Polystyrene Thin Film (Aibn) On Polysciences 30-50Μm Glass Beads Using Cetyltrimethyl-Ammonium Bromide Surfactant, David Langford Jan 2017

Development Of Standard Operating Procedure: Admicellar Polymerization Of Polystyrene Thin Film (Aibn) On Polysciences 30-50Μm Glass Beads Using Cetyltrimethyl-Ammonium Bromide Surfactant, David Langford

Honors Theses

Poly(1-phenylethene), commonly referred to as Polystyrene, is one of the world's most common polymers. Made from the monomer styrene (ethenylbenzene), this polymer is used in a wide range of products from packing peanuts to disposable cutlery. The method of polymerization used in this research project is called admicellar polymerization. This process consists of four main steps: admicelle formation, adsolubilization, polymerization, and removal of admicelle and polymer. Admicellar polymerization has a number of advantages over related methods of thin film polymerization including simplicity and low cost of components and process.


Thermal Denox Optimization: A Case Study In Fluid Catalytic Cracking, David E. Rozier Jan 2017

Thermal Denox Optimization: A Case Study In Fluid Catalytic Cracking, David E. Rozier

Honors Theses

This thesis will first provide background information on fluid catalytic cracking (FCC), a highly important unit operation to the process of petroleum refining, and a description of Thermal DeNOx, an environmental treatment system common to FCC units and other process units where high temperature furnaces are used. Next, this thesis will detail a project which I had the chance to lead as a process engineering intern at ExxonMobil's Baton Rouge Refinery in the fall of 2016. The objective of the project was to optimize Thermal DeNOx systems installed on two FCC units at the refinery. Experiments were conducted on these …


Pens Up! The Development Of The Ole Miss Ballpoint Pen, Vera M. Gardner, Andrew M. Huff, Charles B. Mceuen Jan 2017

Pens Up! The Development Of The Ole Miss Ballpoint Pen, Vera M. Gardner, Andrew M. Huff, Charles B. Mceuen

Honors Theses

This thesis will document and analyze the ideation, research and design, production, and optimization processes for the Center for Manufacturing Excellence Senior Capstone design project. The Pens Up! team consisted of six team members- four mechanical engineering majors, one accounting major, and one business major- working together to continuously improve the Ole Miss ballpoint pen's quality, design, and to standardize and eliminate wastes to its production process. After months of preparing and testing various ideas and ironing out kinks and mistakes, Pens Up! was able to produce a quality aluminum pen. This thesis will describe the various obstacles faced as …


The Pharmacodynamic Functions Of Low-Dose Rapamycin As A Model For Universal Influenza Protection, William Gust Jan 2017

The Pharmacodynamic Functions Of Low-Dose Rapamycin As A Model For Universal Influenza Protection, William Gust

Honors Theses

One of the most sought after breakthroughs in modern influenza research is the creation of a universal influenza vaccine that would protect against all strains of avian influenza. An unlikely model for this kind of protection might be found in the mTOR inhibitor rapamycin. Traditionally used to prevent organ transplant rejection, low doses of rapamycin have been found to protect mice against infection with distinct subtypes of influenza. However, it is not understood how a partial block in this pathway provides optimal heterosubtypic immunity. Interestingly, previous experiments have shown that low dose rapamycin inhibits germinal center formation to reduce antibody …


Evaluation Of Sigma Ligand Az66 Analgesic Potentiation Of Cannabinoids, Jacqueline Morris Jan 2017

Evaluation Of Sigma Ligand Az66 Analgesic Potentiation Of Cannabinoids, Jacqueline Morris

Honors Theses

Sigma receptors have become a popular subject for research the past few decades, but there is still much mystery behind these receptors and how they work. Sigma receptors, like cannabinoid-1 (CB1) receptors, have effects on the human body including appetite regulation, depression, and analgesia. AZ66 is a highly selective sigma receptor ligand that has antagonistic properties. Sigma receptor antagonists have been shown to potentiate the analgesic effects of opiates; however, there are no known literature reports about the interaction between the sigma receptor system and the endocannabinoid system, including CB1 receptors. The purpose of this study is to evaluate AZ66 …


Synthesis Of Difluoromethyl And Monofluoromethyl Ketones For Biological Evaluation At The Gaba-B Receptor, Mallory Maier Jan 2017

Synthesis Of Difluoromethyl And Monofluoromethyl Ketones For Biological Evaluation At The Gaba-B Receptor, Mallory Maier

Honors Theses

The central nervous system communicates using neurotransmitters. Most are excitatory neurotransmitters, such as acetylcholine, dopamine, and serotonin, but


Synthesis And Biological Evaluation Of Cannabinoid Receptor Ligands, Mariah Leigh Cole Jan 2017

Synthesis And Biological Evaluation Of Cannabinoid Receptor Ligands, Mariah Leigh Cole

Honors Theses

The cannabinoid receptors, members of the G-protein coupled receptor (GPCR) superfamily, have been implicated in numerous human physiological functions and diseases. These receptors, cannabinoid type 1 (CB1) and cannabinoid type 2 (CB2), are most concentrated in the central nervous system and immune cells, respectively, and have each become a target of therapeutic interest. Dual CB1/CB2 agonists such as delta-9-tetrahydrocannbinol (THC) have demonstrated efficacy in the treatment of nausea, pain, and glaucoma, but suffer from psychotropic effects mediated by CB1, motivating the search for CB2 selective therapeutic agents. Selective modulation of the CB2 receptor has therapeutic potential in human health disorders …


Reducing The Interfacial Tension Of Magnetic Surfactants In Magnetic Fields, Rachel Anne Stanhope Jan 2017

Reducing The Interfacial Tension Of Magnetic Surfactants In Magnetic Fields, Rachel Anne Stanhope

Honors Theses

This thesis discusses the theory, experimental research methods, and findings of the effects that magnetic fields have on the interfacial tension of magnetic surfactant solutions. Analyzing how magnetic fields affect the properties of magnetic surfactants, including interfacial tension, is the first step to creating low energy, magnetic field induced separations to address the problem of growing energy demands for chemical and biological separations [1]. Surfactants are organic structures that contain both a hydrophilic head group and a hydrophobic tail, which aggregate toward the interface of solutions and decrease the interfacial tension until the critical micelle concentration is reached. Magnetic surfactants …


City Of Gresham Stormwater Retrofit Master Plan, Teresa F. Huntsinger Jan 2017

City Of Gresham Stormwater Retrofit Master Plan, Teresa F. Huntsinger

Civil and Environmental Engineering Master's Project Reports

The Stormwater Retrofit Master Plan identifies more than 50 stormwater retrofit project opportunities across three watersheds in the City of Gresham. The retrofit projects are prioritized in a scoring system to evaluate the costs and benefits of diverse project sizes and types. Project types range from bioswales and planters in city parking lots and along arterial roads, to regional end-of-pipe facilities and retrofits of existing detention ponds. Top projects will move forward for further assessment, design and construction, helping the city achieve its water quality improvement goals. The scoring system may be used to evaluate additional projects in the future.


Impact Of Speed On Vehicle Safety On Urban Arterial Roadways, Andrew C. Vosper Jan 2017

Impact Of Speed On Vehicle Safety On Urban Arterial Roadways, Andrew C. Vosper

Civil and Environmental Engineering Master's Project Reports

Vehicle speed has long been one, if not the primary contributing factor to crashes, influencing both the probability and severity. Within the Portland metro area arterials have the highest serious crash rate per road mile and vehicle miles travelled. (Metro, 2012) The purpose of this research is to compile vehicle speeds along select arterial roadways within the Portland metro area and comparing it to applicable crash data. The roadway segment of SE Foster Road between SE 52nd avenues and SE 82nd avenues was selected, due to the simplicity of the physical as-built roadway properties along with available Bluetooth …


Seismic Retrofit Case Study Of Reinforced Concrete Bridges With Buckling Restrained Braces, Michael K. Miotke Jan 2017

Seismic Retrofit Case Study Of Reinforced Concrete Bridges With Buckling Restrained Braces, Michael K. Miotke

Civil and Environmental Engineering Master's Project Reports

Many highway bridges in Oregon have been designed with minimal considerations for seismic hazard and are in need of retrofit. Although buckling restrained braces (BRBs) are not necessarily a new concept, using them to seismically retrofit bridges is. This case study investigates the BRB retrofit concept as compared to traditional retrofit measures for a sample of typical vulnerable bridges in Oregon. The objectives of evaluating these cases were to determine the feasibility of the concept both in terms of performance as well as construction costs. This study builds on the ongoing research at Portland State University into the development of …


Development Of Laboratory Scale Conical Spouted Bed Reactors, James Blake Gegenheimer Jan 2017

Development Of Laboratory Scale Conical Spouted Bed Reactors, James Blake Gegenheimer

LSU Master's Theses

Conical spouted beds (CSBs) are a form of a fluidized bed that is characteristic of its spouting behaviors. The conical spouted bed has a small inlet that diverges through a conical section towards a larger fixed-diameter column which is filled with static spouting media. By injecting a fluid at a sufficient velocity, a small spout will form in which the spouting media will become entrained by the fluid particles and carried to the top of the system where it will circulate back into the system. It has been shown that CSB reactors have the potential for increasing the heat circulation …


Estimation Of Rfid Tag Population Size By Gaussian Estimator, Md Mahmudul Hasan Jan 2017

Estimation Of Rfid Tag Population Size By Gaussian Estimator, Md Mahmudul Hasan

LSU Master's Theses

Radio Frequency IDenti cation (RFID) systems are prevalent in all sorts of daily life endeavors. In this thesis we propose a new method to estimate RFID tag population size. We have named our algorithm "Gaussian Estimation of RFID Tags,"namely, GERT. We present GERT under both {0,1} and {0,1,e} channel models, and in both cases the estimator we use is a well justi ed Gaussian random variable for large enough frame size based on Central Limit Theorem for triangular arrays. The most prominent feature of GERT is the quality with which it estimates a tag population size. We support all the …


Recommending Sustainable Design Practices By Characterizing Activities And Mindsets, Jeremy Faludi Jan 2017

Recommending Sustainable Design Practices By Characterizing Activities And Mindsets, Jeremy Faludi

Dartmouth Scholarship

How do designers, engineers, and managers choose the best sustainable design method for their work? How can different design practices combine to complement each other? This study makes recommendations by deconstructing 14 design methods, guides, certifications, and other practices into their constituent activities and mindsets, then characterizing those activities and mindsets. For example, some of the seven activity categories are analysis, ideation, and goal-setting; some of the eight mindset categories are priorities, abstract versus concrete goals, and environmental versus social goals. Recommendations are given for matching sustainable design practices to different usage contexts by their constituent activities and mindsets. It …


Environmental Impacts Of Selective Laser Melting: Do Printer, Powder, Or Power Dominate?, Jeremy Faludi, Martin Baumers, Ian Maskery, Richard Hague Jan 2017

Environmental Impacts Of Selective Laser Melting: Do Printer, Powder, Or Power Dominate?, Jeremy Faludi, Martin Baumers, Ian Maskery, Richard Hague

Dartmouth Scholarship

This life cycle assessment measured environmental impacts of selective laser melting, to determine where most impacts arise: machine and supporting hardware; aluminum powder material used; or electricity used to print. Machine impacts and aluminum powder impacts were calculated by generating life cycle inventories of materials and processing; electricity use was measured by in‐line power meter; transport and disposal were also assessed. Impacts were calculated as energy use (megajoules; MJ), ReCiPe Europe Midpoint H, and ReCiPe Europe Endpoint H/A. Previous research has shown that the efficiency of additive manufacturing depends on machine operation patterns; thus, scenarios were demarcated through notation listing …


Cyberpdx: A Camp For Broadening Participation In Cybersecurity, Wu-Chang Feng, Robert Liebman, Lois Delcambre, Michael Mooradian Lupro, Tim Sheard, Scott Britell, Gerald W. Recktenwald Jan 2017

Cyberpdx: A Camp For Broadening Participation In Cybersecurity, Wu-Chang Feng, Robert Liebman, Lois Delcambre, Michael Mooradian Lupro, Tim Sheard, Scott Britell, Gerald W. Recktenwald

University Studies Faculty Publications and Presentations

With society’s increasing dependence on technology infrastructure, the importance of securing the computers, networks, data, and algorithms that run our digital and physical lives is becoming critical. To equip the next generation of citizens for the challenges ahead, an effort is underway to introduce security content early in a student’s academic career. It is important that these efforts broaden participation and increase diversity in the field. While many camps and curricula focus on introducing technical content and skills related to cybersecurity, such approaches can prematurely limit how students view career opportunities in the field, potentially limiting those who ultimately pursue …


Experimental Study Of Frequency Oscillations In Islanded Power System, Kevin Daniel Wellman Jan 2017

Experimental Study Of Frequency Oscillations In Islanded Power System, Kevin Daniel Wellman

LSU Master's Theses

Since the introduction of power electronics to the grid, the power system has quickly changed. Fault detection and removal is performed more accurately and at quicker response time, and non-inertia driven loads have been added. This means stability must continue to be a main topic of concern to maintain a stable synchronized grid. In this thesis a lab was designed, constructed, and tested for the purpose of studying transient stability in power systems. Many different options were considered and researched, but the focus of this paper is to describe the options chosen. The lab must be safe to operate and …


Simulation And Analysis Of Switched Reluctance Generator For Renewable Energy Applications, Simone Sartori, Malabika Basu, Michael Farrell, Andrea Tortella Jan 2017

Simulation And Analysis Of Switched Reluctance Generator For Renewable Energy Applications, Simone Sartori, Malabika Basu, Michael Farrell, Andrea Tortella

Conference papers

The purpose of the paper is to investigate the application of a Switched Reluctance Generator (SRG) for future wave energy converters. This machine presents some favourable features as compared to others. The machine optimal operation can be obtained after a detailed assessment of the control strategy. For this purpose, a SRG model is implemented in Matlab® Simulink® environment to find out the values of the switching angles which maximize the converted power and to set up an appropriate control of the power exchange with the grid to which the machine is connected. The simulation results provide evidence that a proper …


The Different Stages Of Prpd Pattern For Negative Point To Plane Corona Driven By A Dc Voltage Containing A Ripple, Tobias Dezenzo, Thomas Betz, Andreas Schwarzbacher Jan 2017

The Different Stages Of Prpd Pattern For Negative Point To Plane Corona Driven By A Dc Voltage Containing A Ripple, Tobias Dezenzo, Thomas Betz, Andreas Schwarzbacher

Articles

This paper presents the different patterns, which can be observed by means of a phase resolved partial discharge analysis, when a negative dc voltage is applied to a point to plane arrangement in air. The required phase relation is obtained due to the ripple being present on the dc voltage generated by a half-wave rectification. Phase resolved partial discharge patterns are given from corona onset to glow inception. Discharge pulses appearing at the test object are used to support physical explanations of the pattern occurrence. It is shown that five clearly identifiable patterns accompany the evolution of corona discharges when …


Assessing Peer Review By Gauging The Fate Of Rejected Manuscripts: The Case Of The Journal Of Artificial Societies And Social Simulation, Niccolò Casnici, Francisco Grimaldo, Nigel Gilbert, Pierpaolo Dondio, Flaminio Squazzoni Jan 2017

Assessing Peer Review By Gauging The Fate Of Rejected Manuscripts: The Case Of The Journal Of Artificial Societies And Social Simulation, Niccolò Casnici, Francisco Grimaldo, Nigel Gilbert, Pierpaolo Dondio, Flaminio Squazzoni

Articles

This paper investigates the fate of manuscripts that were rejected from JASSS-The Journal of Artificial Societies and Social Simulation, the flagship journal of social simulation. We tracked 456 manuscripts that were rejected from 1997 to 2011 and traced their subsequent publication as journal articles, conference papers or working papers. We compared the impact factor of the publishing journal and the citations of those manuscripts that were eventually published against the yearly impact factor of JASSS and the number of citations achieved by the JASSS mean and top cited articles. Only 10% of the rejected manuscripts were eventually published in a …


Computational Studies On Biomechanics Of Concussion And On Efficacy Of Football Helmets, David Labyak Jan 2017

Computational Studies On Biomechanics Of Concussion And On Efficacy Of Football Helmets, David Labyak

Dissertations, Master's Theses and Master's Reports

Football helmets have been used for many years to prevent head injuries to players. Over the years, the helmet design has evolved from a crude leather head covering to the more recent form fitting helmets that are seen today. The one design feature that has been common in the majority of all helmets is a hard polycarbonate shell with a foam cushion padding. The main goal of the padding layer was to reduce the amount of linear acceleration during an impact event. The one feature that has been overlooked is how stiff the padding is in rotation.

The purpose of …


Utilizing Reprap Style 3d Printers For The Manufacturing Of Composite Heat Exchangers, John Laureto Jan 2017

Utilizing Reprap Style 3d Printers For The Manufacturing Of Composite Heat Exchangers, John Laureto

Dissertations, Master's Theses and Master's Reports

The low cost 3D printing market is currently dominated by the application of RepRap (self-replicating rapid-prototyper) variants. Presented in this document are practical utilizations of RepRap technology. Developed are innovative processes to manufacture composite materials systems for thermal management solutions.

First, a laser polymer welder system is validated by quantifying maximum peak load and weld width of linear low density polyethylene (LLDPE) lap welds as a function of linear energy density. The development of practical engineering data, in this application, is critical to producing mechanically durable welds. Developed laser and printer parameter sets allow for manufacturing of LLDPE multi-layered heat …


A Study Of High Temperature Heat Pipes And The Impact Of Magnetic Field On The Flow Of Liquid Metal, Udit Sharma Jan 2017

A Study Of High Temperature Heat Pipes And The Impact Of Magnetic Field On The Flow Of Liquid Metal, Udit Sharma

Dissertations, Master's Theses and Master's Reports

A study of high temperature heat pipe was conducted to understand its characteristics. A review of working fluid, temperature, wick structure, problems, operational limit and applications was done. Alkali metal were concluded as the most viable candidate for the working fluid.

The impact of three parameters namely magnetic field, heat flux and temperature was analyzed on the performance of HTHP (High Temperature Heat Pipe). The presence of magnetic field had the most considerable impact on reducing the pumping limit of the heat pipe while the temperature had almost negligible effect. Magnetic field results in the pressure drop and adversely affect …


Evaluation Of Thermal Stability Of Ausferrite In Austempered Ductile Iron Using Differential Scanning Calorimetry, Karl Warsinski Jan 2017

Evaluation Of Thermal Stability Of Ausferrite In Austempered Ductile Iron Using Differential Scanning Calorimetry, Karl Warsinski

Dissertations, Master's Theses and Master's Reports

Austempered Ductile Iron (ADI) is prone to changes in microstructure and mechanical properties when exposed to elevated service temperatures. Differential Scanning Calorimetry has been used to evaluate the stabilizing effects of copper, nickel, molybdenum, and cobalt on the ausferrite structure. Previous studies have conflated the effects of various alloy additions, and little effort has been made to systematically catalog the effects of individual elements. The focus of the current research has been to identify alloying elements that more strongly stabilize the ausferrite structure in order to improve service life of ADI at elevated temperatures. Nickel has been shown to have …


Analysis Of Aeroelastic Effects On The 3-Dimensional Interference Of Wind-Turbine Rotors, Anurag Rajan Jan 2017

Analysis Of Aeroelastic Effects On The 3-Dimensional Interference Of Wind-Turbine Rotors, Anurag Rajan

Dissertations, Master's Theses and Master's Reports

Greater penetration of wind energy demands better utilization of available wind. This has led to a formidable increase in the rotor diameter over the past few years. Bigger rotors call for lighter, more flexible blades to reduce loads and improve fatigue life. As a result, future blades will deform substantially more than the relatively stiff blades of the past. More efficient use of wind power also calls for incorporating advanced active and passive control strategies and increasing the range of velocities over which wind energy is captured. Hence an improvement in the quality of numerical simulations capable of capturing the …


Control Of A Powered Ankle-Foot Prosthesis: From Perception To Impedance Modulation, Guilherme Aramizo Ribeiro Jan 2017

Control Of A Powered Ankle-Foot Prosthesis: From Perception To Impedance Modulation, Guilherme Aramizo Ribeiro

Dissertations, Master's Theses and Master's Reports

Active ankle prostheses controllers are demonstrating gaining smart features to improve the safety and comfort offor users. The perception of user intention to modulate the ankle dynamics is a well-known example of such feature. But not much work focused on the perception of the environment, nor how the environment should be included in the mechanical design and control of the prosthesisprostheses. The proposed work aims to improve the feasibility of integrate the environment perception integration intoto the prostheses controllersler, and to define the desired ankle dynamics, as mechanical impedance, duringof the human walk on different environmental settings. As a preliminary …


Life Cycle Assessment (Lca) Of Ore Transportation Route Alternatives For Eagle Mine, Soumith Kumar Oduru Jan 2017

Life Cycle Assessment (Lca) Of Ore Transportation Route Alternatives For Eagle Mine, Soumith Kumar Oduru

Dissertations, Master's Theses and Master's Reports

Transportation sector at large is a major consumer of fossil fuels and constitutes more than a quarter of the global greenhouse gas emissions. When making infrastructure route and mode choice decisions for new freight-oriented projects, it is important that environmental and emissions considerations are included as an integral part of the selection process. Emissions from freight transportation projects related to mining and natural resource industry are especially critical, as they involve high volumes and tonnages often in pristine environments. The most logical time for emissions analysis is during modal and route analysis that are often conducted in the planning stage …


Molecular Modeling Of Aerospace Polymer Matrices Including Carbon Nanotube-Enhanced Epoxy, Matthew Radue Jan 2017

Molecular Modeling Of Aerospace Polymer Matrices Including Carbon Nanotube-Enhanced Epoxy, Matthew Radue

Dissertations, Master's Theses and Master's Reports

Carbon fiber (CF) composites are increasingly replacing metals used in major structural parts of aircraft, spacecraft, and automobiles. The current limitations of carbon fiber composites are addressed through computational material design by modeling the salient aerospace matrix materials. Molecular Dynamics (MD) models of epoxies with and without carbon nanotube (CNT) reinforcement and models of pure bismaleimides (BMIs) were developed to elucidate structure-property relationships for improved selection and tailoring of matrices.

The influence of monomer functionality on the mechanical properties of epoxies is studied using the Reax Force Field (ReaxFF). From deformation simulations, the Young’s modulus, yield point, and Poisson’s ratio …


Model-Based Control Of An Rcci Engine, Akshat Abhay Raut Jan 2017

Model-Based Control Of An Rcci Engine, Akshat Abhay Raut

Dissertations, Master's Theses and Master's Reports

Reactivity controlled compression ignition (RCCI) is a combustion strategy that offers high fuel conversion efficiency and near zero emissions of NOx and soot which can help in improving fuel economy in mobile and stationary internal combustion engine (ICE) applications and at the same time lower engine-out emissions. One of the main challenges associated with RCCI combustion is the difficulty in simultaneously controlling combustion phasing, engine load, and cyclic variability during transient engine operations.

This thesis focuses on developing model based controllers for cycle-to-cycle combustion phasing and load control during transient operations. A control oriented model (COM) is developed by using …