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

Engineering Commons

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

2017

Discipline
Institution
Keyword
Publication
Publication Type
File Type

Articles 1 - 30 of 8774

Full-Text Articles in Engineering

Mems Fabrication Of A Peristaltic Pump, Nicholas Amendola Dec 2017

Mems Fabrication Of A Peristaltic Pump, Nicholas Amendola

Journal of the Microelectronic Engineering Conference

No abstract provided.


Automated Droplet Manipulation Through Electrowetting On Dielectric For Solid-Phase Oligonucleotide Synthesis, Hee Tae An Dec 2017

Automated Droplet Manipulation Through Electrowetting On Dielectric For Solid-Phase Oligonucleotide Synthesis, Hee Tae An

Journal of the Microelectronic Engineering Conference

No abstract provided.


Development Of Economic Water Usage Sensor And Cyber-Physical Systems Co-Simulation Platform For Home Energy Saving, Joe Singer Dec 2017

Development Of Economic Water Usage Sensor And Cyber-Physical Systems Co-Simulation Platform For Home Energy Saving, Joe Singer

Mechanical Engineering Master's Theses

In this thesis, two Cyber-Physical Systems (CPS) approaches were considered to reduce residential building energy consumption. First, a flow sensor was developed for residential gas and electric storage water heaters. The sensor utilizes unique temperature changes of tank inlet and outlet pipes upon water draw to provide occupant hot water usage. Post processing of measured pipe temperature data was able to detect water draw events. Conservation of energy was applied to heater pipes to determine relative internal water flow rate based on transient temperature measurements. Correlations between calculated flow and actual flow were significant at a 95% confidence level. Using ...


16-11 Microsimulation Of The Impact Of Access Management Practices To Pedestrians, Deo Chimba, Kevin Soloka Dec 2017

16-11 Microsimulation Of The Impact Of Access Management Practices To Pedestrians, Deo Chimba, Kevin Soloka

Transportation Research Center Reports

The study applied microsimulation to analyze the impact of access management (AM) to the operational performances of vehicles and pedestrians. A conceptual model was developed in VISSIM and VISWALK to examine the effect of access and signals density on different median types to the travel speed, travel time, delay and stopping. Access density, signal density, and presence of median were simulated in a scenario base analysis. The model scenarios shifted through changing both access density and signal density with no median, raised median and TWLT lane to provide interactions of arterial corridors in Nashville. The effect of access density on ...


16-02 Enhancing Non-Motorized Mobility Within Construction Zones, Upul Attanayake, Abul Fazal Mazumder, Wjdan Dhaif Sahi Sahi, Mathew Mueller, Dustin Black Dec 2017

16-02 Enhancing Non-Motorized Mobility Within Construction Zones, Upul Attanayake, Abul Fazal Mazumder, Wjdan Dhaif Sahi Sahi, Mathew Mueller, Dustin Black

Transportation Research Center Reports

Acquisition of lanes and sidewalks for construction activities increases congestion and delays and compromises safety. Further, work zones impair access to local businesses, bus stops, nearby facilities, etc., while hindering mobility of pedestrians, cyclists, and emergency responders. The emphasis on non-motorized mobility varies significantly when temporary traffic control management plans are developed for small cities. Due to lack of specific instructions given to contractors and the potential liability issues, contractors tend to completely close access to non-motorized traffic without providing alternate routes or detours. Instead of using a detour, pedestrians and cyclists tend to pass through the construction zone or ...


Vulnerability Assessment Of Sign-Support Structures During Transportation And In Service, Saeed Arabi Dec 2017

Vulnerability Assessment Of Sign-Support Structures During Transportation And In Service, Saeed Arabi

Graduate Theses and Dissertations

Dynamic Message Signs (DMSs) are increasingly used in highways as an effective means to communicate time-sensitive information with motorists. To ensure their long-term performance, it is critical to ensure that the truss structures that hold them can resist not only extreme loading events, but also fatigue induced by service loads. For this purpose, a comprehensive study has been conducted on the fatigue performance of this important category of structures. The current study evaluates the fatigue performance of DMS-support structures during transportation under road-induced excitations as well as throughout their service life under loads induced by environmental stressors. In the first ...


Computational And Experimental Determination Of The Mixing Efficiency Of A Microfluidic Serpentine Micromixer, Siril Arockiam Dec 2017

Computational And Experimental Determination Of The Mixing Efficiency Of A Microfluidic Serpentine Micromixer, Siril Arockiam

Theses

In microfluidics, efficiency and mixing time are the greatest disadvantages. These parameters hinder the application of microfluidic devices for biochemical and immunological assays. However, once these disadvantages have been overcome by optimizing th


Formulation Of Uv Curable Resins Utilized In Vat Photo Polymerization For The Additive Manufacturing Of Gun Propulsion Charge In 3d Printers, David T. Bird Dec 2017

Formulation Of Uv Curable Resins Utilized In Vat Photo Polymerization For The Additive Manufacturing Of Gun Propulsion Charge In 3d Printers, David T. Bird

Theses

Formulating resins for Additive Manufacturing (AM), utilizing UV laser stereolithography, is a new technique that makes it possible for the fabrication of complex geometries with high dimensional resolution. This layer by layer photopolymerization appr


Electrical Properties Of Metal/Wse2structures, Zeel Rajiv Gandhi Dec 2017

Electrical Properties Of Metal/Wse2structures, Zeel Rajiv Gandhi

Theses

The formation of low resistance metal contacts on two-Dimensional layer (2-D) of WSe2 is a big challenge. In this research, a comparative study is presented on the electrical properties of metal/WSe2 Schottky barrier diodes with various metals such as


Carbon Fiber Electrodes For In Vivo Neural Recording, Esma Cetinkaya Dec 2017

Carbon Fiber Electrodes For In Vivo Neural Recording, Esma Cetinkaya

Theses

Multi-channel micro electrodes for neural recording is a growing field that thrives on novel materials and fabrication techniques offered by micro fabrication technology. The material and the design of microelectrodes have a critical role on the qualit


Comparative Analysis Of The Dissolution Performance Of Aspirin Tablets In The Usp Apparatus 2 And In A Minivessel Dissolution System, Annmarie C. Walker Dec 2017

Comparative Analysis Of The Dissolution Performance Of Aspirin Tablets In The Usp Apparatus 2 And In A Minivessel Dissolution System, Annmarie C. Walker

Theses

Dissolution testing is a critical component of quality control procedures in the pharmaceutical industry in order to ensure that the final solid dosage forms have consistent dissolution properties. Dissolution tests are also routinely conducted to eval


Assessment Of Nanocomposites Vs. Amorphous Solid Dispersions For Dissolution Enhancement Of Bcs Class Ii Drugs, Meng Li Dec 2017

Assessment Of Nanocomposites Vs. Amorphous Solid Dispersions For Dissolution Enhancement Of Bcs Class Ii Drugs, Meng Li

Dissertations

Nanoparticle-based formulations (nanocomposites) and amorphous solid dispersions, shortly ASDs, are two major pharmaceutical formulation platforms used for the bioavailability enhancement of poorly water-soluble drugs. While they both have several advantages-disadvantages, a scientific comparative assessment of their drug release performance and dissolution mechanisms at different drug doses is not available. With the goal of addressing this issue, the dissertation aims to achieve three major objectives: (1) develop a processing-formulation understanding of wet media milling process for fast-efficient production of drug nanoparticles in stable nanosuspension form, (2) elucidate the impact of various classes dispersants on drug release rate and mechanisms during the ...


Evaluating The Impact Of Adopting 3d Printing Services On The Retailers, Sharareh Rajaei Dehkordi Dec 2017

Evaluating The Impact Of Adopting 3d Printing Services On The Retailers, Sharareh Rajaei Dehkordi

Dissertations

As additive manufacturing technology becomes more responsive to consumers’ demand, one important question for the retailers is whether they should provide 3D printing services in their brick-and-mortar store in addition to the traditional off-the-shelf product? If so, what should be the retailers pricing scheme to achieve a higher profit? What should be the optimal inventory level of off-the-shelf products? What is the optimal capacity of 3D printers? In this study, stochastic models are examined to capture the joint optimal 3D product price and capacity of 3D printers to maximize retailer’s expected profit while considering consumer product choices. Moreover, a ...


Simulation, Performance And Interference Analysis Of Multi-User Visible Light Communication Systems, Adel Aldalbahi Dec 2017

Simulation, Performance And Interference Analysis Of Multi-User Visible Light Communication Systems, Adel Aldalbahi

Dissertations

The emergence of new physical media such as optical wireless, and the ability to aggregate these new media with legacy networks motivate the study of heterogeneous network performance, especially with respect to the design of protocols to best exploit the characteristics of each medium.


Characterization Of Microporous Ectfe Membranes Exposed To Different Liquid Media And ?-Radiation And Nanoparticle Microfiltration Through Such Membranes, Na Yao Dec 2017

Characterization Of Microporous Ectfe Membranes Exposed To Different Liquid Media And ?-Radiation And Nanoparticle Microfiltration Through Such Membranes, Na Yao

Dissertations

Microporous polymeric membranes are used in a variety of applications for separations, purification as well as barrier function. A major application is for microfiltration (MF). Changes in the properties of MF membranes exposed to acids, bases and organic solvents are of interest in semiconductor processing as well as in membrane contactor applications. Microfiltration membranes used for sterilization in beverage, biotechnology and pharmaceutical industries are sterilized by gamma radiation among others. Irradiation-induced degradation in membrane properties should be known. A variety of fluoropolymer-based microporous membranes are available with varying properties. Ethylene chlorotrifluoroethylene (ECTFE) membranes are a new addition and are of ...


Co2 Reduction Over Noble Metal/Carbon Nanotube Catalyst, Yuan Zhu Dec 2017

Co2 Reduction Over Noble Metal/Carbon Nanotube Catalyst, Yuan Zhu

Dissertations

Carbon nanotube-based Pt/Pd and Ru catalysts, independently synthesized by a microwave reaction technique, show good catalytic activity for CO2 reduction in the contexts of dry reforming (DR) of methane (CH4 + CO2 -> 2CO + 2H2) and reverse water gas shift (RWGS) (H2 + CO2 -> CO + H2O). Reaction temperatures range from 773 to 973 K, with system pressure at 30 psig. The feed molar ratios CH4/CO2 and CO2/H2 are varied from 0.5 to 2.0. Reactant conversions in DR and RWGS are strongly influenced by temperature and feed molar ratio, but ...


Optimization Of The Front End Of Cdte Solar Cells, Yunfei Chen Dec 2017

Optimization Of The Front End Of Cdte Solar Cells, Yunfei Chen

Dissertations

The front end of CdTe solar cells consists of two layers: a transparent conducting oxide (TCO) layer and a window layer. New wider band gap materials, ZnMgO are being used to replace CdS as the window layer for the purpose of removing blue loss. For ZnMgO, three important parameters, including the atomic Mg content (x), thickness (t), and doping concentration (n) can play important roles on the performance of CdTe solar cells. In this dissertation, systematic simulation, by solar cell capacitance simulator (SCAPS), and experiments are used to investigate the influences of these parameters on the performance of CdTe ...


General Design Procedure For Free And Open-Source Hardware For Scientific Equipment, Shane W. Oberloier, Joshua M. Pearce Dec 2017

General Design Procedure For Free And Open-Source Hardware For Scientific Equipment, Shane W. Oberloier, Joshua M. Pearce

Department of Materials Science and Engineering Publications

Distributed digital manufacturing of free and open-source scientific hardware (FOSH) used for scientific experiments has been shown to in general reduce the costs of scientific hardware by 90–99%. In part due to these cost savings, the manufacturing of scientific equipment is beginning to move away from a central paradigm of purchasing proprietary equipment to one in which scientists themselves download open-source designs, fabricate components with digital manufacturing technology, and then assemble the equipment themselves. This trend introduces a need for new formal design procedures that designers can follow when targeting this scientific audience. This study provides five steps in ...


Monitoring Of Corrosion Process In Structural Adhesive Using Smart Materials, Yee Yan Lim, Iman Izadgoshasb, Scott T. Smith Dec 2017

Monitoring Of Corrosion Process In Structural Adhesive Using Smart Materials, Yee Yan Lim, Iman Izadgoshasb, Scott T. Smith

Dr Iman Izadgoshasb

The use of structural adhesives, such as epoxy, for the strengthening and repair of civil infrastructure is gaining popularity in the engineering community. Of particular concern to the viability of intervention measure is the degradation of strength and durability of the epoxy over time, especially when exposed to aggressive environments. Monitoring the corrosion process of epoxy is thus essential to ensure safety of the host structure. In this paper, the electromechanical impedance (EMI) technique that employs a smart piezoelectric transducer is used to monitor the degradation process of commercially available epoxy when exposed to corrosive environments. Standard epoxy coupons with ...


Luminescence Of Defects In The Structural Transformation Of Layered Tin Dichalcogenides, Peter Sutter, H.P. Komsa, A. V. Krasheninnikov, Y Huang, Eli A. Sutter Dec 2017

Luminescence Of Defects In The Structural Transformation Of Layered Tin Dichalcogenides, Peter Sutter, H.P. Komsa, A. V. Krasheninnikov, Y Huang, Eli A. Sutter

Faculty Publications from the Department of Electrical and Computer Engineering

Layered tin sulfide semiconductors are both of fundamental interest and attractive for energy conversion applications. Sn sulfides crystallize in several stable bulk phases with different Sn:S ratios (SnS2, Sn2, S3, and SnS), which can transform into phases with a lower sulfur concentration by introduction of sulfur vacancies (VS). How this complex behavior affects the optoelectronic properties remains largely unknown but is of key importance for understanding light-matter interactions in this family of layered materials. Here, we use the capability to induce VS and drive a transformation between few-layer SnS2 and SnS by electron beam irradiation, combined with in-situ cathodoluminescence ...


A Post-American World? Assessing The Cognitive And Attitudinal Impacts Of Challenges To American Exceptionalism, Jason Gilmore, Charles Rowling Dec 2017

A Post-American World? Assessing The Cognitive And Attitudinal Impacts Of Challenges To American Exceptionalism, Jason Gilmore, Charles Rowling

Languages, Philosophy, and Communication Studies Faculty Publications

A number of voices have emerged in U.S. political discourse questioning the legitimacy of American exceptionalism, suggesting we are in a “post-American world.” Our research examines the effects that political messages that explicitly challenge American exceptionalism can have on U.S. public opinion. Drawing upon social identity theory, we find that explicit challenges to American exceptionalism significantly impact Americans’ views toward their own nation, their willingness to denigrate foreign publics, and their broader foreign policy preferences.


Double Hysteresis Loops At Room Temperature In Nanbo3-Based Lead-Free Antiferroelectric Ceramics, Xiaoli Tan, Zunping Xu, Xiaoming Liu, Zhongming Fan Dec 2017

Double Hysteresis Loops At Room Temperature In Nanbo3-Based Lead-Free Antiferroelectric Ceramics, Xiaoli Tan, Zunping Xu, Xiaoming Liu, Zhongming Fan

Materials Science and Engineering Publications

Polarization-field double hysteresis loops have hardly ever been observed at room temperature in polycrystalline NaNbO3, one of a few lead-free antiferroelectric compounds. In this Letter, it is shown that the exposure of a modified NaNbO3 ceramic to bipolar electric fields of ±160 kV/cm at 100°C can preserve the double hysteresis loops at room temperature. These double hysteresis loops can still be observed after 125 days room temperature aging with some decay in maximum polarization. Frequency dependence analysis suggests that the double hysteresis loops originate from the antiferroelectric ↔ ferroelectric phase transition, not the charged defects.

A novel electrical treatment ...


Microfluidic Pore Model Study On Physical And Geomechanical Factors Influencing Fluid Flow Behavior In Porous Media, Shuang Cao Dec 2017

Microfluidic Pore Model Study On Physical And Geomechanical Factors Influencing Fluid Flow Behavior In Porous Media, Shuang Cao

LSU Doctoral Dissertations

Fluid flow in porous media is a subject of fundamental importance and relevant to numerous engineering applications. The comprehensive description of fluid interaction parameters containing wetting properties, fluid-fluid displacement ratio, and capillary pressure, are inevitably needed. Moreover, the fine-grained sediments’ response to various pore fluids and migration in porous media influences reservoir geomechanical properties and pore clogging is essential to a better understanding of fluids flow behavior.

This dissertation provides a detailed study of physical and geomechanical factors influencing fluids flow behavior in porous media. The two-dimensional micromodel tests have been conducted under a wide selection of fluids flow conditions ...


Texture Development And Coercivity Enhancement In Cast Alnico 9 Magnets, Wenyong Zhang, Shah Valloppilly, Xingzhong Li, Lanping Yue, Ralph Skomski, Iver E. Anderson, Matthew J. Kramer, Wei Tang, Jeff Shield, David J. Sellmyer Dec 2017

Texture Development And Coercivity Enhancement In Cast Alnico 9 Magnets, Wenyong Zhang, Shah Valloppilly, Xingzhong Li, Lanping Yue, Ralph Skomski, Iver E. Anderson, Matthew J. Kramer, Wei Tang, Jeff Shield, David J. Sellmyer

Ames Laboratory Accepted Manuscripts

The effect of Y addition and magnetic field on texture and magnetic properties of arc-melted alnico 9 magnets has been investigated. Small additions of Y (1.5 wt.%) develop a (200) texture for the arc-melted alnico 9 magnet. Such a texture is hard to form in cast samples. To achieve this goal, we set up a high-field annealing system with a maximum operation temperature of 1250 °C. This system enabled annealing in a field of 45 kOe with subsequent draw annealing for the solutionized buttons; we have been able to substantially increase remanence ratio and coercivity, from 0.70 and ...


Smart-Based Monitoring Of Epoxy Using Piezoelectric Transducers, Yee Yan Lim, Iman Izadgoshasb, Scott T. Smith Dec 2017

Smart-Based Monitoring Of Epoxy Using Piezoelectric Transducers, Yee Yan Lim, Iman Izadgoshasb, Scott T. Smith

Dr Iman Izadgoshasb

Structural adhesives are an important component of strengthening and repair techniques for structures. Adequate and proper curing of such materials is essential to achieve its desired strength and durability. In this study, the curing process of epoxy type Sikadur 330 is monitored using the electromechanical impedance (EMI) technique employing smart piezoelectric material, namely Lead Zirconate Titanate (PZT). Experimental results show that the PZT transducer embedded into the epoxy in liquid state is effective in monitoring the initial setting and the subsequent hardening process of a lab scale epoxy coupon. Rightward movement of both the PZT resonance peaks and the structural ...


Modifications To Commercial Printers To Enable Multi-Material Fabrication Of 3d Cellular Scaffolds, Lucas D. Albrecht Dec 2017

Modifications To Commercial Printers To Enable Multi-Material Fabrication Of 3d Cellular Scaffolds, Lucas D. Albrecht

Theses - ALL

The scarcity of organs for patients that need transplants has led to exceedingly

lengthy waits for organ transplants for sick patients. Fabrication of tissues and organ

constructs in-vitro has potential to end the shortage, however many of the machines

used to create these tissues and organs are expensive, not easy to use, and do not

have any further practical applications. Bioprinting technology has the potential to

revolutionize the fabrication of biological constructs that can be used as in vitro model

tissues and vivo substitutes. Bioprinting is the process of using conventional 3D printing

methods and computer-aided-design (CAD) to create patient ...


Cell Laden Hydrogel Microspheres Using 3d Printed Microfluidics, Sanika Nitin Suvarnapathaki Dec 2017

Cell Laden Hydrogel Microspheres Using 3d Printed Microfluidics, Sanika Nitin Suvarnapathaki

Theses - ALL

Cell laden hydrogel microspheres using 3D printed microfluidics

Abstract

By

Sanika Suvarnapathaki

Current tissue engineering therapies use macro-scale three dimensional (3D) scaffolds to treat tissue defects surgically. Uneven cell seeding and oxygen and media perfusion cause low cell viability in these macro-scale scaffolds. Microencapsulation, a technique of encapsulating cells in biocompatible polymers or hydrogels, has the potential to address these key issues, and therefore this technology has been used for numerous healthcare applications over the last two decades. Cell microencapsulation in hydrogels that mimic the tissue physiology and biochemistry has made it possible to use natural hydrogels like gelatin methacrylate ...


Online Learning With Bandits For Coverage, Mahmuda Rahman Dec 2017

Online Learning With Bandits For Coverage, Mahmuda Rahman

Dissertations - ALL

With the rapid growth in velocity and volume, streaming data compels decision support systems to predict a small number of unique data points in due time that can represent a massive amount of correlated data without much loss of precision. In this work, we formulate this problem as the {\it online set coverage problem} and propose its solution for recommendation systems and the patrol assignment problem.

We propose a novel online reinforcement learning algorithm inspired by the Multi-Armed Bandit problem to solve the online recommendation system problem. We introduce a graph-based mechanism to improve the user coverage by recommended items ...


Adsorption Of Iodine And Water On Silver-Exchanged Mordenite, Yue Nan Dec 2017

Adsorption Of Iodine And Water On Silver-Exchanged Mordenite, Yue Nan

Dissertations - ALL

The reprocessing of used nuclear fuel to recover the fissile materials generates off gases including radioactive nuclides namely 3H (tritiated water, H3HO), 129I, 85Kr, 135Xe, and 14C. Due to its high quantity in off-gas streams and long half-life (1.59 million years), 129I removal from the off-gas streams is a significant objective of off-gas treatment.

129I retention by solid adsorbents was recognized a better strategy in comparison to liquid scrubbers due to the simplicity of system design and low cost. Among the studied adsorbents, reduced silver-exchanged mordenite (Ag0Z) was widely recognized as the state-of-art adsorbent for iodine removal. It has ...


A Life-Cycle Benefit/Cost Analysis Framework For Its Deployments, Xifan Chen Dec 2017

A Life-Cycle Benefit/Cost Analysis Framework For Its Deployments, Xifan Chen

Dissertations - ALL

The primary objective of Transportation Systems Management and Operation (TSM&O) strategies, or Intelligent Transportation Systems (ITS) is to optimize the capacity of existing transportation infrastructure by reducing congestion. Over past decades, agencies and researchers investigated the use of various strategies such as deployment of adaptive traffic control systems (ATCS), ramp metering systems (RMS), surveillance through closed circuit TV (CCTV) cameras, and information sharing systems to achieve this objective. Life Cycle Agency Cost Agency Analysis (LCCA) of various alternative intelligent transportation strategies has received particular attention to identify the strategy with the lowest cost. However, increasing concerns over the impacts ...