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

Digital Commons Network™

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

2012

Discipline
Institution
Keyword
Publication
Publication Type
File Type

Articles 1291 - 1320 of 19376

Full-Text Articles in Entire DC Network

Fem Simulation For Indot Temporary Concrete Anchored Barrier, Efe G. Kurt, Amit H. Varma, Sangdo Hong Dec 2012

Fem Simulation For Indot Temporary Concrete Anchored Barrier, Efe G. Kurt, Amit H. Varma, Sangdo Hong

JTRP Technical Reports

Portable Concrete Barriers (PCBs) are used to redirect errant vehicles to keep them passing to opposing lanes and to ensure safety of the people and any objects behind the barriers. In the state of Indiana, increments to the PCBs, such as L-Shape steel plates, have been applied to enhance the safety performance of these barriers. In this study, Finite Element (FE) analyses are performed to evaluate the safety performance of PCBs with and without the increments and get thorough information about the increments applied. A full-scale crash test (INDOT, 2001) was executed for an impact to the PCBs with a …

Go to article

Sediment Metal Concentrations As A Function Of Land Use In The Charles River, Eastern Massachusetts, Darryl L. Luce Dec 2012

Sediment Metal Concentrations As A Function Of Land Use In The Charles River, Eastern Massachusetts, Darryl L. Luce

Graduate Doctoral Dissertations

Two sediment cores and eleven grab samples collected from the Charles River were analyzed to determine changes to the concentration of metals in sediments due to anthropogenic changes in the watershed. The unique aspect of this research was that sediment cores from the same geologic setting, yet having widely different sources, were compared. The findings from that comparison were used to focus the investigation through the remainder of the Charles River. The radionuclides 210Pb, 214Pb, and 137Cs established the year of deposition in the sediment cores. The concentrations of aluminum (Al), iron (Fe), manganese (Mn), copper (Cu), zinc (Zn), chromium …

Go to article

Sediment Based Turbidity And Bacteria Reduction Analysis In Simulated Construction Site Runoff, James W. Berry Iii Dec 2012

Sediment Based Turbidity And Bacteria Reduction Analysis In Simulated Construction Site Runoff, James W. Berry Iii

All Theses

Large construction projects are highly vulnerable to sediment removal by erosive forces. Turbidity, resulting from this excess sediment, has gained recognition as anindicator of pollution in surface runoff from construction activities. The Environmental Protection Agency (EPA) is currently moving toward regulations that would establish a nationwide maximum turbidity effluent limit discharged from construction sites. Research has shown that current sediment control best management practices (BMPs) are often ineffective at controlling elevated turbidity levels in construction site discharges. Additionally, research confirms that sediment basins may act as reservoirs for bacteria, specifically Escherichia coli (E. coli). During rainfall events, resuspension within sediment …

Go to article

De-Embedding In High Speed Design, Don Degroot, David Dunham Dec 2012

De-Embedding In High Speed Design, Don Degroot, David Dunham

Faculty Publications

No abstract provided.

Go to article

Swift Follow-Up Observations Of Candidate Gravitational-Wave Transient Events, P. A. Evans, J. K. Fridriksson, N. Gehrels, J. Homan, J. P. Osborne, M. Siegel, A. Beardmore, P. Handbauer, J. Gelbord, J. A. Kennea, M. Smith, Q. Zhu, J. Aasi, J. Abadie, B. P. Abbott, R. Abbott, T. D. Abbott, M. Abernathy, T. Accadia, F. Acernese, C. Adams, T. Adams, P. Addesso, R. Adhikari, C. Affeldt, M. Agathos, K. Agatsuma, P. Ajith, B. Allen, A. Allocca, E. Amador Ceron, Tiffany Z. Summerscales Dec 2012

Swift Follow-Up Observations Of Candidate Gravitational-Wave Transient Events, P. A. Evans, J. K. Fridriksson, N. Gehrels, J. Homan, J. P. Osborne, M. Siegel, A. Beardmore, P. Handbauer, J. Gelbord, J. A. Kennea, M. Smith, Q. Zhu, J. Aasi, J. Abadie, B. P. Abbott, R. Abbott, T. D. Abbott, M. Abernathy, T. Accadia, F. Acernese, C. Adams, T. Adams, P. Addesso, R. Adhikari, C. Affeldt, M. Agathos, K. Agatsuma, P. Ajith, B. Allen, A. Allocca, E. Amador Ceron, Tiffany Z. Summerscales

Faculty Publications

We present the first multi-wavelength follow-up observations of two candidate gravitational-wave (GW) transient events recorded by LIGO and Virgo in their 2009-2010 science run. The events were selected with low latency by the network of GW detectors (within less than 10 minutes) and their candidate sky locations were observed by the Swift observatory (within 12 hr). Image transient detection was used to analyze the collected electromagnetic data, which were found to be consistent with background. Off-line analysis of the GW data alone has also established that the selected GW events show no evidence of an astrophysical origin; one of them …

Go to article

Motion Capture Study Of Human Movement Recognition, Nicholas Kinerd Dec 2012

Motion Capture Study Of Human Movement Recognition, Nicholas Kinerd

All Theses

In this thesis, we address questions about recognition of human movement through motion
capture. We begin by capturing the martial arts movements of four actors as they each perform
three different techniques. We then conduct a survey to determine if participants in
the survey are able to distinguish the various martial arts techniques and differentiate the
actors that portray said techniques. A secondary consideration of our survey is to determine
if the participants can distinguish the sex of the actors as they perform the martial arts
techniques. Our hypothesis is that people are able to distinguish actors and sex; however, …

Go to article

Development Of Feature Recognition Algorithm For Automated Identification Of Duplicate Geometries In Cad Models, Aravind Shanthakumar Dec 2012

Development Of Feature Recognition Algorithm For Automated Identification Of Duplicate Geometries In Cad Models, Aravind Shanthakumar

All Theses

This research presents a feature recognition algorithm for the automated identification of duplicate geometries in the CAD assembly. The duplicate geometry is one of the seven indicators of the lazy parts mass reduction method. The lazy parts method is a light weight engineering method that is used for analyzing parts with the mass reduction potential. The duplicate geometry is defined as any geometries lying equal to or within the threshold distance with the user-defined orientation between them and have the percentage similarity that is equal to or greater than the threshold value. The feature recognition system developed in this research …

Go to article

Design Automation And Optimization Of Honeycomb Structures For Maximum Sound Transmission Loss, Rohan Galgalikar Dec 2012

Design Automation And Optimization Of Honeycomb Structures For Maximum Sound Transmission Loss, Rohan Galgalikar

All Theses

Cellular materials with macro effective properties defined by repeated meso-structures are increasingly replacing conventional homogeneous materials due to their high strength to weight ratio, and controllable effective mechanical properties, such as negative Poisson's ratio and tailored orthotropic elastic properties. Honeycomb structures are a well-known cellular material that has been used extensively in aerospace and other industries where the premium on the weight reduction with high-strength is required. Common applications of honeycomb cellular structures are their use as the core material in sandwich plates and plates between two face sheets. Honeycomb structures are built from repetition of a common hexagonal unit …

Go to article

Design And Implementation Of A Genre Hybrid Video Game That Integrates The Curriculum Of An Introductory Programming Course, Cory Buckley Dec 2012

Design And Implementation Of A Genre Hybrid Video Game That Integrates The Curriculum Of An Introductory Programming Course, Cory Buckley

All Theses

Video games have a history of being exploited for education. However, all too fre- quently, the resulting educational video game is either transparent in its hijacking of video game media, or the educational content is not intelligently placed within the context of the game. In this paper we analyze existing educational video games and observe popular commercial video game mechanics to form a more player oriented development mindset. Our approach involves mingling game mechanics that are not commonly used together to create a genre hybrid educational video game with a seamlessly integrated introductory programming curriculum. We use a machine architecture …

Go to article

Evaluation Of 26al Method As Star Formation Rate Indicator, Manjeet Singh Dec 2012

Evaluation Of 26al Method As Star Formation Rate Indicator, Manjeet Singh

All Theses

The aim of this work is to evaluate the '26Al method' used to determine the Galactic Star Formation Rate (SFR) and compare it to other alternative methods. 26Al is a radioactive isotope produced mainly in massive star winds and in the ensuing core collapse supernova explosion. The radioactive 26Al decays with a life time of 106 years by emitting γ- ray photons in 1.808 MeV band. The 26Al method involves using the Galactic 26Al radioactive flux as a tracer. This approach based on the γ- ray line measurements does not suffer from extinction and small number statistics.
To evaluate the …

Go to article

Alternative Energy Sources - Integration Of Power Generation Systems Into A Microgrid At Clemson University And An Atmospheric Thermodynamic Driven Mechanical Clock, Shreyas Patel Dec 2012

Alternative Energy Sources - Integration Of Power Generation Systems Into A Microgrid At Clemson University And An Atmospheric Thermodynamic Driven Mechanical Clock, Shreyas Patel

All Theses

Non-renewable energy sources such as coal, crude oil, and natural gas are being consumed at a brisk pace which is promoting a worldwide energy crisis. The burning of fossil fuels produces greenhouse gases such as carbon dioxide and nitrous oxides as well as soot which contribute to atmospheric pollution. Although fossil fuels will continue to be available for many decades, the amount of petroleum remaining in the earth and its associated cost remains an open issue. The utilization of green energy such as solar and wind offer renewable and pollution free sources. A worldwide shift is slowly underway towards the …

Go to article

Detecting Copper Residues In Sediments From Aquatic Copper-Based Pesticide Applications, Ben Willis Dec 2012

Detecting Copper Residues In Sediments From Aquatic Copper-Based Pesticide Applications, Ben Willis

All Theses

Copper-based algaecides and herbicides are commonly used to mitigate risks of problematic algae and weeds, however there are concerns regarding copper accumulation from treatments. Modeling and laboratory experiments can be used to predict copper accumulation and measurement in sediments, as well as benthic invertebrate responses following treatments. Modeling was used to estimate copper residual concentrations in sediments from algaecide and herbicide treatments. Reported and measured method detection limits (MDLs; minimum concentration of an analyte of interest that can be measured with 99 percent confidence in a specific matrix using an analytical method) were compared to model estimated copper residual concentrations …

Go to article

Semantic Similarity Detection In Natural Language Documents, Lianyu Zhao Dec 2012

Semantic Similarity Detection In Natural Language Documents, Lianyu Zhao

All Theses

Data leak prevention (DLP) solutions monitor and control data flow. Current techniques find data that matches user defined syntactic patterns. Unfortunately, large classes of DLP relevant data are defined by information semantics, rather than data syntax. Syntax refers to data format, whereas semantics refers to data meaning. The class of social security numbers can be adequately expressed using data syntax, whereas a new industrial process can only be adequately described using information semantics. In this paper, we propose methods for extracting and identifying document semantics using training sets of limited size (tens of documents). The first method is based on …

Go to article

Hydromechanical Well Testing Using A 3d Fiber Optic Extensometer, Glenn Skawski Dec 2012

Hydromechanical Well Testing Using A 3d Fiber Optic Extensometer, Glenn Skawski

All Theses

Some fractured rock formations hold important resources, such as water, hydrocarbons or heat, whereas others are good candidates for waste disposal. Hydromechanical well tests have been developed to improve characterization of formation properties and parameter distributions by measuring displacement along with pressure while stressing a well. The displacement that occurs during a well test depends on the geometry of fractures or other sources of permeability, as well as the distribution of compliance or elastic modulus. Current methods of hydromechanical well testing, measures axial displacements along a wellbore, which may cause ambiguity in interpretations when 3-D components of deformation are present. …

Go to article

Study On Corrosion Activity Of Carbon Steel In Concrete Simulated Pore Solution Under Static Tensile And Compressive Stresses, Yujie Zhang Dec 2012

Study On Corrosion Activity Of Carbon Steel In Concrete Simulated Pore Solution Under Static Tensile And Compressive Stresses, Yujie Zhang

All Theses

Reinforced concrete is a structure material made up of concrete with relatively lower tensile strength containing reinforcements with higher tensile strength and better ductility, which are embedded into fresh concrete to resist tensile stress in certain regions of concrete. Steel reinforced concrete is most widely used around the world in civil engineering structures, water conservancy and highway construction due to its durability strength and reasonable cost.
However, reinforced concrete structures such as bridges and parking lots slabs inevitably experience variable loads and constant degradation from the aggressive environments, such as marine and deicing salts. Therefore, it is imperative to study …

Go to article

Objective Bayesian Inference On The Common Mean Of Normal Distributions, Shiyi Tu Dec 2012

Objective Bayesian Inference On The Common Mean Of Normal Distributions, Shiyi Tu

All Theses

One of the oldest problems in statistical area is to make inference on a common mean of several different normal populations with unknown and probably unequal variances. There are several different ways to make inference on the common mean. The most common methods are point estimation, hypothesis testing, and interval estimation. Point estimation uses sample data to calculate a single value serving as a best guess for the unknown population mean. Hypothesis testing assumes all populations have the same mean as the null hypothesis. Interval estimation is an interval of possible values of the unknown mean.
In this paper, we …

Go to article

Development Of A Two-Dimensional Model Of A Pneumatic Tire, Timothy Lewis Dec 2012

Development Of A Two-Dimensional Model Of A Pneumatic Tire, Timothy Lewis

All Theses

The pneumatic tire has been studied extensively since its invention in 1888. With the advent of high-powered computers and the use of the finite element method, the understanding of the tire's complex non-linear behavior has grown tremendously. However, one weakness of finite element models is that parameter studies are difficult and time consuming to perform. In contrast, an analytical model can quickly and easily perform extensive parameter studies. To the knowledge of the author, all existing analytical models of the tire make assumptions concerning the tire's behavior and construction that while useful for obtaining some of the first-order characteristics, are …

Go to article

Impedance-Based Fault Location Methods For Transmission Line Connecting Wind Farm Plants, Chaoqi Ji Dec 2012

Impedance-Based Fault Location Methods For Transmission Line Connecting Wind Farm Plants, Chaoqi Ji

All Theses

With an increasing capacity of wind power installed in the world, the impact of wind generation during fault condition has been studied. Wind plants equipped with induction generator results in a different fault behavior in transmission networks. In this paper, the validation of existing impedance-based fault location methods are performed on a transmission line connecting wind plant equipped with three different types of induction generators. This work is based on the simulation in real-time digital simulator (RTDS).
Squirrel-cage induction generator (SCIG), wound-rotor induction generator (WRIG) and doubly-fed induction generator (DFIG) are the three common generators used for wind power plants. …

Go to article

Composite Sandwich Structures With Honeycomb Core Subjected To Impact, Lei He Dec 2012

Composite Sandwich Structures With Honeycomb Core Subjected To Impact, Lei He

All Theses

Composite sandwich structures constructed with honeycomb core can be an effective means of absorbing impact in many engineer applications. Conventional hexagonal honeycomb exhibit an effective positive Poisson's ratio, are commonly employed due to their lightweight and high axial stiffness properties. In contrast, auxetic honeycombs offer high in-plane shear stiffness, and exhibit negative Poisson's ratios with lateral extension, instead of contraction, when stretched axially.
In this study, the dynamic response of an aluminum composite panel with a honeycomb core constrained within two thin face sheets is investigated undergoing impact with a rigid ball. The finite element models used to simulate impact …

Go to article

Convex Hull Characterization Of Special Polytopes In N-Ary Variables, Ruobing Shen Dec 2012

Convex Hull Characterization Of Special Polytopes In N-Ary Variables, Ruobing Shen

All Theses

This paper characterizes the convex hull of the set of n-ary vectors that are lexicographically less than or equal to a given such vector. A polynomial number of facets is shown to be sufficient to describe the convex hull. These facets generalize the family of cover inequalities for the binary case. They allow for advances relative to both the modeling of integer variables using base-n expansions, and the solving of n-ary knapsack problems with weakly super-decreasing coefficients.

Go to article

An Efficient Image Segmentation Algorithm Using Bidirectional Mahalanobis Distance, Rahul Suresh Dec 2012

An Efficient Image Segmentation Algorithm Using Bidirectional Mahalanobis Distance, Rahul Suresh

All Theses

In this thesis, we present an efficient graph-based image-segmentation algorithm that improves upon the drawbacks of the minimum spanning tree based segmentation algorithm, namely leaks that occur due to the criterion used to merge regions, and the sensitivity of the output to the parameter k. To address these problems, we propose the use of bidirectional Mahalanobis distance, along with a Gaussian model for each region, and an intuitive normalized parameter τ that replaces k and works for all images without having to be changed. Furthermore, we propose an approximation to the algorithm that enables it to run efficiently in O(NlogN) …

Go to article

Study Of Cell Viability During Laser Direct Writing Of Cell-Alginate Suspension, Hemanth Gudapati Dec 2012

Study Of Cell Viability During Laser Direct Writing Of Cell-Alginate Suspension, Hemanth Gudapati

All Theses

Laser-assisted cell printing, developed based on Matrix-assisted pulsed-laser evaporation direct-write (MAPLE DW), a typical LIFT (laser-induced forward transfer) practice, has been emerging as one of the most promising biofabrication techniques. Alginate, particularly sodium alginate, is extensively used as the constituent of bioink in laser-assisted cell printing. However, thus far, studies investigating the effect of alginate gelation on cell viability in laser-assisted cell printing are lacking. The objective of this study is to investigate the effects of gelation, gelation time, sodium alginate concentration, and the effect of operating conditions such as the laser fluence on post-transfer cell viability during laser-assisted cell …

Go to article

Ultraluminous X-Ray Sources In Andromeda Galaxy: Two Recent Discoveries And Their Implications, Amanpreet Kaur Dec 2012

Ultraluminous X-Ray Sources In Andromeda Galaxy: Two Recent Discoveries And Their Implications, Amanpreet Kaur

All Theses

Ultraluminous X-ray sources are believed to be associated with X-ray binaries, in which an accreting black hole generates X-ray luminosities in excess of 10 39 erg/s. The nature of the companion star and the underlying physics of the accretion process is not yet established with certainty. In particular, whether or not the accretion is super/sub Eddington is an open question, as is the mass of the companion star. We discuss the first two ULXs recently discovered in M31 and investigate the nature of their underlying sources. We present the X-ray observations for ULX-1 in detail and discuss its implications for …

Go to article

Investigation Of Auxiliary Winding Harmonic Resonance Phenomena In Single Phase Induction Motors, Gaurav Singh Dec 2012

Investigation Of Auxiliary Winding Harmonic Resonance Phenomena In Single Phase Induction Motors, Gaurav Singh

All Theses

In recent years, the proliferation of single phase power electronics based loads has given rise to a number of power quality issues in the power grid. Harmonics in voltage and current waveforms are one of the biggest problems in this family of power quality issues. Until some years back, power system utilities did not consider harmonics due to small single phase loads to be a big problem. In fact, only large loads were considered as potential hotspots for power quality problems. However, the advent of compact fluorescent lamps (CFLs), personal computers and consumer electronic devices, which utilize rectifier front ends, …

Go to article

Can The Application Of A Landscape Designed Learning Environment Enhance Education?, Virginia Bailey Dec 2012

Can The Application Of A Landscape Designed Learning Environment Enhance Education?, Virginia Bailey

All Theses

There is a need for a restructuring the way that a child's learning environment is designed. Currently, the mainstream educational design process ignores the notion that children have different ways of learning. Furthermore, when there are so many distractions, how we successfully reach a child's mind has become a challenge. The current school system is structured in a manner that does not address the presence of these distractions, often causing overstimulation and inattentiveness. Designing for children should be approached in a way that all senses are engaged. Having opportunities for hands-on learning inside and outside of the classroom is important …

Go to article

Reverse Osmosis Desalination With Integrated Compressed Air Energy Storage: Conceptual Design And Modeling, Pooja Mahajan Dec 2012

Reverse Osmosis Desalination With Integrated Compressed Air Energy Storage: Conceptual Design And Modeling, Pooja Mahajan

All Theses

Growing fresh water needs have led to an interest in water desalination using reverse osmosis (RO) membranes. Energy consumption has a large share in the expenses incurred to drive a reverse osmosis desalination system. With depleting fossil fuel reserves, tapping renewable sources of energy is a promising alternative to meet the energy requirements. Wind power coupled to an RO desalination system is a potential means of delivering clean water using sustainable energy. This work investigates modeling of a conceptual wind-energy-driven RO desalination system that is made possible because of an air-pressure energy storage mechanism. Bench-scale experiments were performed on an …

Go to article

Visions & Fissures, Sarah Butler Dec 2012

Visions & Fissures, Sarah Butler

All Theses

My work references both Early Renaissance paintings and digital technology through highly-saturated and detailed hybrids of painting styles. The religious narratives combined with digital symbols and artifacts of digital processes suggest the spiritual undercurrents surrounding digital technology in its potential for enlightenment, transcendence, and evoking a sense of the infinite. To further clarify the reasoning behind this connection, I discuss three themes. Firstly, the function of illusion in Early Renaissance and in digital space, secondly, the mythology and promise associated with digital space and lastly, the fact that we currently occupy two spaces simultaneously as computer users, and aligning that …

Go to article

Shock Attenuation In Landing, Bryon Christopher Applequist Dec 2012

Shock Attenuation In Landing, Bryon Christopher Applequist

UNLV Theses, Dissertations, Professional Papers, and Capstones

Shock attenuation (SA) has been well studied in activities such as walking and running (Chu, et al. 2004; Derrick, et al. 2004; Mercer, et al. 2003); however, there is a lack of research regarding SA during landing. Furthermore, there is lack of information regarding which structures attenuate shock. The purpose of this study was to examine SA among the leg-hip, hip-head, and leg-head segments during landing. Each subject (n=10, Age 26.3 ± 2.71 years, Height 1.68 ± 0.08 m, Mass 70.49 ± 16.03 kg) was instrumented with accelerometers at the leg, hip and forehead. Subjects then performed landings from three …

Go to article

Investigating The Impacts Of Conventional And Advanced Treatment Technologies On Energy Consumption At Satellite Water Reuse Plants, Jonathan Roy Bailey Dec 2012

Investigating The Impacts Of Conventional And Advanced Treatment Technologies On Energy Consumption At Satellite Water Reuse Plants, Jonathan Roy Bailey

UNLV Theses, Dissertations, Professional Papers, and Capstones

With the ever increasing world population and the resulting increase in industrialization and agricultural practices, depletion of two of the world's most important natural resources, water and fossil fuels, is inevitable. Water reclamation and reuse is the key to protecting these natural resources. Water reclamation using smaller decentralized wastewater treatment plants, known as satellite water reuse plants (WRP), have become popular in the last decade. With stricter standards and regulations on effluent quality and requirements for a smaller land footprint (i.e. real estate area), additional treatment processes and advanced technologies are needed. This greatly increases the energy consumption of an …

Go to article

Leading Transformational Change In A Large Urban School District, Leslie Jean Brinks Dec 2012

Leading Transformational Change In A Large Urban School District, Leslie Jean Brinks

UNLV Theses, Dissertations, Professional Papers, and Capstones

This abstract reflects the findings of the understanding of the skills necessary to lead transformative change in a non-affluent neighborhood in a large urban district. Current research and understandings of transformative leadership has been limited to traits and organizational concepts rather than the work associated with transforming schools. Studies seldom addressed if leaders even valued the actions central to transformative work or if they have the capacity and expertise to do the task. The purpose of this study was to understand the kinds of knowledge, skills, and dispositions that support what is viewed as transformative leading. Additionally the inquiry probed …

Go to article

First Prev Next Last