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2013

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Articles 691 - 720 of 7289

Full-Text Articles in Engineering

D-Sparq: Distributed, Scalable And Efficient Rdf Query Engine, Raghava Mutharaju, Sherif Sakr, Alessandra Sala, Pascal Hitzler Oct 2013

D-Sparq: Distributed, Scalable And Efficient Rdf Query Engine, Raghava Mutharaju, Sherif Sakr, Alessandra Sala, Pascal Hitzler

Computer Science and Engineering Faculty Publications

We present D-SPARQ, a distributed RDF query engine that combines the MapReduce processing framework with a NoSQL distributed data store, MongoDB. The performance of processing SPARQL queries mainly depends on the efficiency of handling the join operations between the RDF triple patterns. Our system features two unique characteristics that enable efficiently tackling this challenge: 1) Identifying specific patterns of the input queries that enable improving the performance by running different parts of the query in a parallel mode. 2) Using the triple selectivity information for reordering the individual triples of the input query within the identified query patterns. The preliminary …

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Editing R2rml Mappings Made Easy, Kunal Sengupta, Peter Haase, Michael Schmidt, Pascal Hitzler Oct 2013

Editing R2rml Mappings Made Easy, Kunal Sengupta, Peter Haase, Michael Schmidt, Pascal Hitzler

Computer Science and Engineering Faculty Publications

The new W3C standard R2RML3 defines a language for ex- pressing mappings from relational databases to RDF, allowing applications built on top of the W3C Semantic Technology stack to seamlessly integrate relational data. A major obstacle in using R2RML, though, is the creation and maintenance of mappings. In this demo, we present a novel R2RML mapping editor which provides a user interface to create and edit mappings interactively even for non-experts.

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Engineered Nanotopography On Electrospun Plla Microfibers Modifies Raw 264.7 Cell Response, Nicholas J. Schaub, Tara Britton, Rupak Rajachar, Ryan J. Gilbert Oct 2013

Engineered Nanotopography On Electrospun Plla Microfibers Modifies Raw 264.7 Cell Response, Nicholas J. Schaub, Tara Britton, Rupak Rajachar, Ryan J. Gilbert

Chemical and Biochemical Engineering Faculty Research & Creative Works

In this study, we created a new method of electrospinning capable of controlling the surface structure of individual fibers (fiber nano topography). The nano topographical features were created by a phase separation in the fibers as they formed. To control the phase separation, a nonsolvent (a chemical insoluble with the polymer) was added to an electrospinning solution containing poly-l-lactic acid (PLLA) and chloroform. The nano topography of electro spun fibers in the PLLA/chloroform solution was smooth. However, adding a small weight (< 2% of total solution) of a single nonsolvent (water, ethanol, or dimethyl sulfoxide) generated nanoscale depressions on the surface of the fibers unique to the nonsolvent added. Additionally, nanoscale depressions on electro spun fibers were observed to change with dimethyl sulfoxide (DMSO) concentration in the PLLA/chloroform solution. A nonlinear relationship was found between the concentration of DMSO and the number and size of nano topographical features. The surface depressions did not alter the hydrophobicity of the scaffold or degradation of the scaffold over a two-day period. To determine if fiber nano topography altered cell behavior, macrophages (RAW 264.7 cells) were cultured on fibers with a smooth nano topography or fibers with nanoscale depressions. RAW 264.7 cells spread less on fibers with nanoscale depressions than fibers with a smooth topography (p < 0.05), but there were no differences between groups with regard to cell metabolism or the number of adherent cells. The results of this study demonstrate the necessity to consider the nano topography of individual fibers as these features may affect cellular behavior. More importantly, we demonstrate a versatile method of controlling electro spun fiber nano topography. © 2013 American Chemical Society.

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Cost Of Housing Regulation In Utah Valley-Impact Fees, Rhett M. Turner, Dr. Howard Bashford Oct 2013

Cost Of Housing Regulation In Utah Valley-Impact Fees, Rhett M. Turner, Dr. Howard Bashford

Journal of Undergraduate Research

The purpose of impact fees is to help fund infrastructure needs brought on by new growth. The State of Utah has recently passed legislation which allows cities to charge impact fees for the construction of new homes. These impact fees can be substantial, amounting to thousands of dollars for each home.

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Mammalian Cells Preferentially Internalize Hydrogel Nanodiscs Over Nanorods And Use Shape-Specific Uptake Mechanisms, Rachit Agarwal, Vikramjit Singh, Patrick Jurney, Li Shi, S. Sreenivasan, Krishnendu Roy Oct 2013

Mammalian Cells Preferentially Internalize Hydrogel Nanodiscs Over Nanorods And Use Shape-Specific Uptake Mechanisms, Rachit Agarwal, Vikramjit Singh, Patrick Jurney, Li Shi, S. Sreenivasan, Krishnendu Roy

Faculty Publications

Size, surface charge, and material compositions are known to influence cell uptake of nanoparticles. However, the effect of particle geometry, i.e., the interplay between nanoscale shape and size, is less understood. Here we show that when shape is decoupled from volume, charge, and material composition, under typical in vitro conditions, mammalian epithelial and immune cells preferentially internalize disc-shaped, negatively charged hydrophilic nanoparticles of high aspect ratios compared with nanorods and lower aspect-ratio nanodiscs. Endothelial cells also prefer nanodiscs, however those of intermediate aspect ratio. Interestingly, unlike nanospheres, larger-sized hydrogel nanodiscs and nanorods are internalized more efficiently than their smallest counterparts. …

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Modeling The Relaxation Time Of Dna Confined In A Nanochannel, Douglas R. Tree, Yanwei Wang, Kevin D. Dorfman Oct 2013

Modeling The Relaxation Time Of Dna Confined In A Nanochannel, Douglas R. Tree, Yanwei Wang, Kevin D. Dorfman

Faculty Publications

Using a mapping between a Rouse dumbbell model and fine-grained Monte Carlo simulations, we have computed the relaxation time of λ-DNA in a high ionic strength buffer confined in a nanochannel. The relaxation time thus obtained agrees quantitatively with experimental data [Reisner et al., Phys. Rev. Lett. 94, 196101 (2005)] using only a single O(1) fitting parameter to account for the uncertainty in model parameters. In addition to validating our mapping, this agreement supports our previous estimates of the friction coefficient of DNA confined in a nanochannel [Tree et al., Phys. Rev. Lett. 108, 228105 …

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Global Change Factors On Ecosystem Invasibility, Raj Lal, Jeffrey Dukes, Michael J. Schuster, Nick G. Smith Oct 2013

Global Change Factors On Ecosystem Invasibility, Raj Lal, Jeffrey Dukes, Michael J. Schuster, Nick G. Smith

The Summer Undergraduate Research Fellowship (SURF) Symposium

Current climate and human-induced changes are projected to alter many regimes of ecosystem functioning. It is projected that invasive species, nonnative species that can be of great detriment to an ecosystem, will benefit under these conditions. The Prairie Invasion and Climate Experiment (PRICLE) studies the effects of two global change factors – N addition and altered precipitation – on invasive species success and the traits that are selected for in a mixed-grass prairie ecosystem. PRICLE is a two by two factorial design over three replications in a restored mixed-grass prairie ecosystem. The major findings from the community traits examination of …

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Distel: A Distributed El+ Ontology Classifier, Raghava Mutharaju, Pascal Hitzler, Prabhaker Mateti Oct 2013

Distel: A Distributed El+ Ontology Classifier, Raghava Mutharaju, Pascal Hitzler, Prabhaker Mateti

Computer Science and Engineering Faculty Publications

OWL 2 EL ontologies are used to model and reason over data from diverse domains such as biomedicine, geography and road traffic. Data in these domains is increasing at a rate quicker than the increase in main memory and computation power of a single machine. Recent efforts in OWL reasoning algorithms lead to the decrease in classification time from several hours to a few seconds even for large ontologies like SNOMED CT. This is especially true for ontologies in the description logic EL+ (a fragment of the OWL 2 EL profile). Reasoners such as Pellet, Hermit, ELK etc. make …

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Stringsauto And Mapsss Results For Oaei 2013, Michelle Cheatham, Pascal Hitzler Oct 2013

Stringsauto And Mapsss Results For Oaei 2013, Michelle Cheatham, Pascal Hitzler

Computer Science and Engineering Faculty Publications

StringsAuto and MapSSS are two closely related ontology alignment systems. The StringsAuto matcher seeks to explore the limits of a syntactic-only approach to alignment. The MapSSS system then expands on this work by embedding the syntactic matching of StringsAuto within a more complete alignment system that also makes use of semantic and structural information. In this paper we describe the basic operation of the two systems and discuss their performance in the OAEI 2013 evaluation.

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Operation-State Monitoring And Energization-Status Identification For Underground Power Cables By Magnetic Field Sensing, Xu Sun, Chun Kit Poon, Geoffrey Chan, Cher Leung Sum, Wing Kin Lee, Lijun Jiang, Philip W.T. Pong Oct 2013

Operation-State Monitoring And Energization-Status Identification For Underground Power Cables By Magnetic Field Sensing, Xu Sun, Chun Kit Poon, Geoffrey Chan, Cher Leung Sum, Wing Kin Lee, Lijun Jiang, Philip W.T. Pong

Electrical and Computer Engineering Faculty Research & Creative Works

In this paper, a novel nondestructive method based on magnetic field sensing is proposed for underground power cable operation-state monitoring and energization-status identification. The magnetic field distribution of the cable is studied using finite element method (FEM) for the power cable operating in different states, i.e., current-energized state (the cable is energized and carries load current) and voltage-energized state (the cable is energized but carries no load current). This innovative method can reconstruct all the source parameters of the cable based on a set of measured magnetic field values. Stochastic optimization technique is applied to realize the reconstruction based on …

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A Clamped Dual-Ridged Waveguide Measurement System For The Broadband, Nondestructive Characterization Of Sheet Materials, Milo W. Hyde Iv, Michael J. Havrilla Oct 2013

A Clamped Dual-Ridged Waveguide Measurement System For The Broadband, Nondestructive Characterization Of Sheet Materials, Milo W. Hyde Iv, Michael J. Havrilla

Faculty Publications

A novel two-port probe which uses dual-ridged waveguides for the nondestructive, broadband characterization of sheet materials is presented. The new probe is shown to possess approximately 2 to 3 times the bandwidth of traditional coaxial and rectangular/circular waveguide probe systems while maintaining the structural robustness characteristic of rectangular/circular waveguide probe systems. The theoretical development of the probe is presented, namely, by applying Love’s equivalence theorem and enforcing the continuity of transverse fields at the dual-ridged waveguide apertures, a system of coupled magnetic field integral equations is derived. The system of coupled magnetic field integral equations is solved using the method …

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Validating The Critical Engineering Literacy Test (Celt) With Cognitive Interviews, Margot L. Keimig, Senay Purzer Oct 2013

Validating The Critical Engineering Literacy Test (Celt) With Cognitive Interviews, Margot L. Keimig, Senay Purzer

The Summer Undergraduate Research Fellowship (SURF) Symposium

The CELT learning assessment focuses on the critical thinking skills of engineering students and allows for the improvement of information literacy, one’s ability identifying and implementing important information. With the pairing of cognitive interviewing, the CELT will allow for the identification of errors and will better determine the reasoning in the decisions made by the students taking the test. The CELT test uses multiple choice and open response questions to evaluate the students and the areas where improvements need to be made. Over the course of the year, the students’ information literacy skills will be expanded and then re-evaluated at …

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Visualizing Mechanics: Improving Student Learning Through Video Demonstrations, Blake A. Wetherton, Olumide A. Awofeso, Carolyn E. Creighton, Adam F. Potrzebowski, Charles M. Krousgrill, Jeffrey F. Rhoads Oct 2013

Visualizing Mechanics: Improving Student Learning Through Video Demonstrations, Blake A. Wetherton, Olumide A. Awofeso, Carolyn E. Creighton, Adam F. Potrzebowski, Charles M. Krousgrill, Jeffrey F. Rhoads

The Summer Undergraduate Research Fellowship (SURF) Symposium

The Purdue Mechanics Freeform Classroom (PMFC) is a project that seeks to reform engineering mechanics education by integrating content and technology; enhancing communication between students, their peers, and instructors; accommodating a broader range of learning styles; and facilitating greater depths of understanding. In an attempt to increase the PMFC’s efficacy, a series of demonstration videos has been produced. As demonstrated by the popularity and pervasiveness of websites such as YouTube, short videos have the potential to captivate audiences. As such, these videos have incredible promise in educational contexts. In the PMFC series of videos, entitled Visualizing Mechanics, each imitates the …

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Improving Data Quality For A Dairy Pollutant Emissions Study, Ian K. Hahus, Albert J. Heber Oct 2013

Improving Data Quality For A Dairy Pollutant Emissions Study, Ian K. Hahus, Albert J. Heber

The Summer Undergraduate Research Fellowship (SURF) Symposium

The National Air Emissions Monitoring Study (NAEMS) was sanctioned by the EPA to determine the characteristics of airborne pollutant emissions from confined broiler, egg, pork, and dairy housing. Fifteen representative monitoring sites were selected around the U.S., at which influent and effluent pollutant concentrations were measured in conjunction with airflow and climatic data. Due to the monumental nature of this study and the potential ramifications of its findings, it is of vital importance that the data collected by the researchers and utilized by the EPA be as complete and accurate as possible. To improve the validity of the data collected …

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Active Dense Tensegrity Structure: A Novel Concept For Shape Morphing Structures, Zhiwei Wu, Thomas Siegmund Oct 2013

Active Dense Tensegrity Structure: A Novel Concept For Shape Morphing Structures, Zhiwei Wu, Thomas Siegmund

The Summer Undergraduate Research Fellowship (SURF) Symposium

Shape morphing is of relevance for advanced engineering systems such as future aerospace vehicles. Tensegrity structures, a structure comprised of a set of discontinuous compressed struts held together with a continuous web of tensioned cables, can function as the foundation of a shape morphing system (Keith et al, 2007). However, the classic tensegrity structures may not be ideal in all configurations because the space within the structure is not utilized. As an alternative, the present work proposes a dense tensegrity system as an assembly of cables carrying tensions only and polyhedral elements under compression only. An active dense tensegrity can …

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Cis Map Drawer Visualization System, Hanye Xu, David Ebert Oct 2013

Cis Map Drawer Visualization System, Hanye Xu, David Ebert

The Summer Undergraduate Research Fellowship (SURF) Symposium

U.S. Citizenship and Immigration Services (USCIS) is the government agency that manages immigration to the United States. They are not only working on filing documents, but also analyzing those data they have. They require help from a visualization system to know the trend of immigration among offices across the country over time. We developed a project called CIS Map Drawer that is used to help build a visualization system for USCIS in order to analyze immigration data easily. This system makes use of a map view, a calendar visual representation, line charts, pixel drawing and other analysis tools to improve …

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Detection Of Foodborne Pathogens By Micro-Filtration Using A Continuous Cell Concentrator Device, Klaire E. Jeffries, Eduardo Ximenes, Michael R. Ladisch Oct 2013

Detection Of Foodborne Pathogens By Micro-Filtration Using A Continuous Cell Concentrator Device, Klaire E. Jeffries, Eduardo Ximenes, Michael R. Ladisch

The Summer Undergraduate Research Fellowship (SURF) Symposium

Protecting consumers from foodborne illness is an important health concern facing the food industry today. An important deficiency exposed by foodborne illness is the inability to track contaminated food back to the source in a timely manner. Although there are established methods that detect bacterial pathogen contamination, they are limited in distinguishing viable bacteria reliably and quickly. Currently, food pathogen testing requires lengthy culture steps, which many times are delayed even longer due to the lack of in-house testing labs. Typically, two to three days elapses between when the food is sampled and the test results are available. This study …

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D-Tunes: Configuration Engine For Geo-Replicated Cloud Storage, Jiawei Wang, Sanjay Rao Oct 2013

D-Tunes: Configuration Engine For Geo-Replicated Cloud Storage, Jiawei Wang, Sanjay Rao

The Summer Undergraduate Research Fellowship (SURF) Symposium

When developing a web-based application, developers are facing stringent requirements to balance the latency, scalability and availability for their cloud database. Application developers need a specific replication configuration strategy based on the requirement of their application. To deal with this problem, some geo-replicated cloud strategy systems have emerged recently, like Cassandra. This project serves to design a web tool that can help configure the best replication strategies for geo-distributed data stores, which uses quorum-based protocols. Currently, our web tool D-Tunes, require a minimum input from users and generate specific scripts based on the inputs user provided. The program running these …

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Radiation Intensity Of A Turbulent Sooting Ethylene Flame, Ryan M. Hartman, Jay P. Gore Oct 2013

Radiation Intensity Of A Turbulent Sooting Ethylene Flame, Ryan M. Hartman, Jay P. Gore

The Summer Undergraduate Research Fellowship (SURF) Symposium

Turbulent sooting flame radiation is relevant to applications ranging from fire safety to gas turbine engines. The complex direct interactions of soot and radiation intensity are of particular importance when creating accurate soot prediction models. Previous studies have measured gas-band and broadband radiation intensity from turbulent sooting flames. The focus of the current study is the characterization of radiation intensity emanating from soot. A high-speed infrared camera (FLIR Phoenix) was used to acquire time-dependent quantitative images of radiation intensity of a turbulent sooting ethylene flame. The flame had a Reynolds number of 15,200 and was stabilized on a burner with …

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Web-Based Visual Analytics For Social Media Data, Jun Xiang Tee, David S. Ebert Oct 2013

Web-Based Visual Analytics For Social Media Data, Jun Xiang Tee, David S. Ebert

The Summer Undergraduate Research Fellowship (SURF) Symposium

Social media data provides valuable information about different events, trends and happenings around the world. Visual data analysis tasks for social media data have large computational and storage space requirements. Due to these restrictions, subdivision of data analysis tools into several layers such as Data, Business Logic or Algorithms, and Presentation Layer is often necessary to make them accessible for variety of clients. On server side, social media data analysis algorithms can be implemented and published in the form of web services. Visual Interface can then be implemented in the form of thin clients that call these web services for …

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Cellulose Nanocrystals As A Material For Microencapsulation, Lauren C. Kennedy, Congwang Ye, Colton Steiner, Carlos Martinez Oct 2013

Cellulose Nanocrystals As A Material For Microencapsulation, Lauren C. Kennedy, Congwang Ye, Colton Steiner, Carlos Martinez

The Summer Undergraduate Research Fellowship (SURF) Symposium

Cellulose is an abundant, biodegradable, and inexpensive renewable polymer that is light in weight with high mechanical strength (Habibi, Lucia, Rojas 2010). Full fibers of cellulose have been used in many products such as plastics and textiles for over a century and a half, but recently, modern extraction techniques have made it possible to investigate uses for minuscule cellulose fibers (Habibi, Lucia, Rojas 2010). Through acid hydrolysis, cellulose fibers become rod-like nanostructures with a high aspect ratio that are known as Cellulose Nanocrystals (CNCs) (Habibi, Lucia, Rojas 2010). Since CNCs are biodegradable and derive from a renewable resource, finding ways …

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An Approximation Method For Solving Complex Electromagnetics Problems Using The Volume Integral Equation, Ryan Nobis, Dan Jiao, Saad Omar Oct 2013

An Approximation Method For Solving Complex Electromagnetics Problems Using The Volume Integral Equation, Ryan Nobis, Dan Jiao, Saad Omar

The Summer Undergraduate Research Fellowship (SURF) Symposium

Solving complex electric field problems can lead researchers to a host of electronic characteristics about an inhomogeneous, complex object. However due to the complexity of these electric fields, a computer needs to be used in order to solve them. Due to the size of the matrices for some problems, methods for improving speed and performance for these algorithms are absolutely necessary. A Volume Integral Equation was used to solve the Electric Field Displacement, D, and approximate the differential term in this equation. The problem was next discretized using phasors, so that it can computationally be solved. Data used to form …

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Next Generation Crystal Viewing Tool, Zach Schaffter, Gerhard Klimeck Oct 2013

Next Generation Crystal Viewing Tool, Zach Schaffter, Gerhard Klimeck

The Summer Undergraduate Research Fellowship (SURF) Symposium

The science and engineering community is limited when it comes to crystal viewing software tools. Each tool lacks in a different area such as customization of structures or visual output. Crystal Viewer 2.0 was created to have all of these features in one program. This one tool simulates virtually any crystal structure with any possible material. The vtkvis widget offers users advanced visual options not seen in any other crystal viewing software. In addition, the powerful engine behind Crystal Viewer 2.0, nanoelectronic modeling 5 or (NEMO5), performs intensive atomic calculations depending on user input. A graphical user interface, or GUI, …

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The Use Of Near Infrared And Microwave Sensing For On-Line Real Time Monitoring Of Moisture Content And Composition Of Powder Blend, Ryan V. Mcdonnell, Anshu Gupta, John Austin, Michael T. Harris, Gintaras V. Reklaitis Oct 2013

The Use Of Near Infrared And Microwave Sensing For On-Line Real Time Monitoring Of Moisture Content And Composition Of Powder Blend, Ryan V. Mcdonnell, Anshu Gupta, John Austin, Michael T. Harris, Gintaras V. Reklaitis

The Summer Undergraduate Research Fellowship (SURF) Symposium

Online process analytics has been a topic of interest by pharmaceutical companies as a method of determining how operating parameters affect the final quality of their products. One form of online process analytics that has been found to be effective is microwave sensing. While it has been found that microwave resonance sensing can be used to measure parameters such as moisture content and density, it has yet to be discovered if such sensors have the ability to measure changes in content uniformity of raw materials pharmaceutical companies use. Data was collected using a spin riffler fitted with a microwave sensor …

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Efficiently Dispersing Carbon Nanotubes In Polyphenylene Sulfide, Kevin M. Sommer, R. Byron Pipes Oct 2013

Efficiently Dispersing Carbon Nanotubes In Polyphenylene Sulfide, Kevin M. Sommer, R. Byron Pipes

The Summer Undergraduate Research Fellowship (SURF) Symposium

Thermal plastics are replacing conventional metals in the aerospace, sporting, electronics, and other industries. Thermal plastics are able to withstand relatively high temperatures, have good fatigue properties, and are lighter than metals. Unfortunately, they are not very electrically conductive. However, adding carbon nanotubes to thermal plastics such as polyphenylene sulfide (PPS) can drastically increase the plastic's conductivity at a low weight percent of nanotubes called the percolation threshold. The percolation threshold is the point where adding a little more carbon nanotubes brings together the network of nanotubes and greatly increases the conductivity. We need to learn how to increase the …

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Optimization Of Polymer Separation By Gradient Polymer Elution Chromatography, Gideon R. Liem, Linda Nien-Hwa Wang Oct 2013

Optimization Of Polymer Separation By Gradient Polymer Elution Chromatography, Gideon R. Liem, Linda Nien-Hwa Wang

The Summer Undergraduate Research Fellowship (SURF) Symposium

High Performance Liquid Chromatography (HPLC) has been a versatile separation method for polymers for many years. Analysis of different polymers by HPLC is typically done by utilizing the differential solubility of the polymers by mixing a good solvent and an anti-solvent in various compositions. This method is called Gradient Polymer Elution Chromatography (GPEC). While GPEC has been used extensively, it commonly uses a linear gradient to separate components. Linear solvent gradients consume a lot of solvent and take a relatively long time (> 30 minutes) to complete. The goal of this study is to develop a step gradient from a …

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Elementary Studies Of Twisted Bilayer Graphene, Branden P. Burns, Yong P. Chen Oct 2013

Elementary Studies Of Twisted Bilayer Graphene, Branden P. Burns, Yong P. Chen

The Summer Undergraduate Research Fellowship (SURF) Symposium

In the nanotechnology field, some existing materials and applications are harmful to the environment, not efficient for certain tasks, or too expensive to be fully utilized. Graphene is a strong and cheap material that can be used to improve current nanotechnologies for more practical uses in society. Twisted bilayer graphene (TBG) is an orientation of graphene layers that exhibit different properties than regular bilayer graphene. It is made by placing a single layer of graphene on top of another at an angle with respect to the other lattice orientation. Understanding the characteristics of TBG is important to uncover more physics …

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Computer Simulation Study Of Slipper Lubrication In Hydraulic Machines, Jordyn B. Miller, Monika Ivantysynova Oct 2013

Computer Simulation Study Of Slipper Lubrication In Hydraulic Machines, Jordyn B. Miller, Monika Ivantysynova

The Summer Undergraduate Research Fellowship (SURF) Symposium

Hydraulic pumps and motors are vital components used in many applications today. Specifically, the axial piston pump is important because it is reliable, relatively compact, and has a high horsepower-to-weight ratio. These features make this type of pump very advantageous in hydraulic systems. Maintaining proper lubrication between surfaces in an axial pump, such as the slipper and swashplate, is imperative in order to have smooth operation of the system and prevent metal-to-metal contact. The aim of this research is to find the optimal slipper design and fluid film thickness to simultaneously maintain a balanced pressure and decrease power loss in …

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Thin Electrical Double Layer Simulation Of Micro-Electrochemical Supercapacitors, Kaitlyn Fisher, Guoping Xiong, Timothy S. Fisher Oct 2013

Thin Electrical Double Layer Simulation Of Micro-Electrochemical Supercapacitors, Kaitlyn Fisher, Guoping Xiong, Timothy S. Fisher

The Summer Undergraduate Research Fellowship (SURF) Symposium

The deteriorating state of the environment has drawn many people to hybrid electric vehicles. Electrochemical micro-supercapacitors are of interest in this field because of their high power density relative to other micro-power sources. However, little is known about how the properties of the electrolyte used affect the performance of such devices. The first step of this investigation was to use thermoreflectance microscopy to measure the temperature change of the electrodes while charging and discharging supercapacitor samples. The components of these samples were graphitic petal electrodes with a Ti/Au covering (for enhanced light reflectance) on a SiO2 base, with a …

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Prism - Materials Simulation Tool, Ryan Widjaja, Marisol Koslowski Oct 2013

Prism - Materials Simulation Tool, Ryan Widjaja, Marisol Koslowski

The Summer Undergraduate Research Fellowship (SURF) Symposium

MEMS (Micro-electromechanical System) is a combined electrical and mechanical nano-scaled device with rapidly growing applications. We have developed a contacting radio frequency capacitive MEMS that is commonly used as capacitive switches and contact actuators in PRISM (Prediction of Reliability, Integrity and Survivability of Microsystems) lab at Purdue University. Our research team has focused on creating a simulation of MEMS’s survivability towards crazing and cracking. Our particular objective in this project is to create a tool that can help users perform complex quantitative calculations regarding the properties of different materials. This tool will generate various plots visualizing the properties, such as …

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