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Full-Text Articles in Physical Sciences and Mathematics

Comparative Analysis Of Forecasting Techniques With Intermittent Demand, John Deforest Dec 2008

Comparative Analysis Of Forecasting Techniques With Intermittent Demand, John Deforest

Industrial Engineering Undergraduate Honors Theses

The world and life are filled with uncertainty. Statistics, and more specifically, forecasting techniques allow us to quantify uncertainty and make decisions based on that information. Many find forecasting advantageous in areas such as predicting consumer demand, stock prices, terrorist attacks, epidemiology, etc. This thesis will focus on forecasting intermittent demand, which is the study of analyzing sporadic demand. One application includes an airplane manufacturer’s sporadic or intermittent demand for spare parts in their distribution center. Since spare parts are not needed on any regular schedule, it is thought of as intermittent. Knowing the projected quantity for a given time …


Service Oriented Transitive Closure Solution, Jonathan Baran Aug 2008

Service Oriented Transitive Closure Solution, Jonathan Baran

Computer Science and Computer Engineering Undergraduate Honors Theses

The goal of this project is a service based solution that utilizes parallel and distributed processing algorithms to solve the transitive closure problem for a large dataset. A dataset may be view conceptually as a table in a database, with a physical structure representing a file containing a sequence of records and fields. Two records are said to be transitively related if and only if they are directly related due to sharing of one or more specific fields, or a sequence may be made from one record to the other under the condition that all intermediate entries are related the …


Developing Subgrade Inputs For Mechanistic-Empirical Pavement Design, Meagan Berlau May 2008

Developing Subgrade Inputs For Mechanistic-Empirical Pavement Design, Meagan Berlau

Computer Science and Computer Engineering Undergraduate Honors Theses

The Resilient Modulus (MR) of a subgrade soil is an essential input into the flexible pavement design models contained in the American Association of State Highway and Transportation Official’s new pavement design guide, the MechanisticEmpirical Pavement Design Guide (MEPDG). For most inputs required for pavement design, there are three levels of input that can be used within the MEPDG system. Level One requires the engineer to enter a value for subgrade Resilient Modulus based on the results of Resilient Modulus tests conducted in the laboratory. Level Two allows the user to input values for other soil property tests including California …


Adding Virtual Rfid To Second Life, Casey Bailey May 2008

Adding Virtual Rfid To Second Life, Casey Bailey

Computer Science and Computer Engineering Undergraduate Honors Theses

Second Life (SL) is a popular online 3D multi-player virtual world where the limits of creating objects and scripting interactions among objects and avatars are based on the player's imagination and scripting skill. Real life, by comparison, is often limited by current technology more than creativity. This thesis investigates a new way to merge reality and virtual reality, in particular, by modeling one emerging real world technology, radio frequency identification (RFID), in the SL virtual world. We investigate how RFID can be deployed and tested in a virtual world, a modeled healthcare facility, as a step before the much more …


Location-Based Hashing For Querying And Searching, Felix Ching May 2008

Location-Based Hashing For Querying And Searching, Felix Ching

Computer Science and Computer Engineering Undergraduate Honors Theses

The rapidly growing information technology in modern days demands an efficient searching scheme to search for desired data. Locality Sensitive Hashing (LSH) is a method for searching similar data in a database. LSH achieves high accuracy and precision for locating desired data, but consumes a significant amount of memory and time. Based on LSH, this thesis presents two novel schemes for efficient and accurate data searching: Locality Sensitive Hashing-SmithWaterman (LSH-SmithWaterman) and Secure Min-wise Locality Sensitive Hashing (SMLSH). Both methods dramatically reduce the memory and time consumption and exhibit high accuracy in data searching. Simulation results demonstrate the efficiency of the …


Visualization Of An Approach To Data Clustering, Marisabel Guevara May 2008

Visualization Of An Approach To Data Clustering, Marisabel Guevara

Computer Science and Computer Engineering Undergraduate Honors Theses

Using visualization and clustering goals as guidelines, this thesis explores a graphic implementation of a data clustering technique that repositions vertices by applying physical laws of charges and springs to the components of the graph. The resulting visualizations are evidence of the success of the approach as well as of the data sets that lend themselves to a clustering routine. Due to the visual product of the implementation, the algorithm is most useful as an aid in understanding the grouping pattern of a data set. Either for a rapid analysis or to assist in presentation, the visual result of the …


An Efficient Hardware Implementation Of Target Recognition Algorithms And Investigation Of Secure Wireless Communication For A Modified Manet, Stephen Barnes May 2008

An Efficient Hardware Implementation Of Target Recognition Algorithms And Investigation Of Secure Wireless Communication For A Modified Manet, Stephen Barnes

Computer Science and Computer Engineering Undergraduate Honors Theses

This paper presents a scheme for effective wireless security of a open broadcast mobile ad-hoc network, MANET, network without significant loss of bandwidth and data integrity through a double tiered encryption scheme, and the feasibility of reducing the target tracking algorithm in [1] into a compact and efficient hardware package. Due to the open nature of MANET, modifications are necessary to secure wireless data in a potential hostile environment. Furthermore, due to power and processing limitations of small unmanned aerial vehicles (UAVs) and the processing intensive calculations of image processing, a sample hardware implementation of key functions of the target …


Holistic Characterization Of Parallel Programming Models In A Distributed Memory Environment, Christopher Bryan May 2008

Holistic Characterization Of Parallel Programming Models In A Distributed Memory Environment, Christopher Bryan

Computer Science and Computer Engineering Undergraduate Honors Theses

The popularity of cluster computing has increased focus on usability, especially in the area of programmability. Languages and libraries that require explicit message passing have been the standard. New languages, designed for cluster computing, are coming to the forefront as a way to simplify parallel programming. Titanium and Fortress are examples of this new class of programming paradigms. This work holistically characterizes these languages and contrasts them with the standard model of parallel programming, and presents benchmark results of small computational kernels written in these languages and models.


Pitch Correction On The Human Voice, Suzanne Ownbey May 2008

Pitch Correction On The Human Voice, Suzanne Ownbey

Computer Science and Computer Engineering Undergraduate Honors Theses

Singing is an excellent way to achieve fame, granted one can sing on key. Alternatively, a person who does not inherently have this ability or want to spend the time practicing to achieve it could use a programmatic solution to pitch correction. Proprietary products already exist that can correct the pitch of a singer, but the average mediocre singer may not be willing or able to purchase them. The focus of this research is to use the basic frequency altering algorithm of resampling, which alters the length of the wave to correct the pitch of a note. Small parts of …


Multiuav2 Agent Swarming For Distributed Atr Simulation, Kyle White May 2008

Multiuav2 Agent Swarming For Distributed Atr Simulation, Kyle White

Computer Science and Computer Engineering Undergraduate Honors Theses

Traditional automatic target recognition (ATR) is performed by unmanned aerial vehicles (UAVs) depending on a central control tower to provide the high level organization of the system. The UAVs fly through a region of interest to identify targets and relay all communication through a central control tower. The centralized approach to ATR has limited fault-tolerance, scalability with regards to the number of UAVs, and susceptibility to malicious attacks on the central tower [2]. A swarm-driven alternative [1] is extended with a communication control scheme to address fault-tolerance and scalability while utilizing the higher onboard processing power now available for UAVs …


Computer Generation And Processing Of Music: Pitch Correction For The Human Voice, Jason Hardy May 2008

Computer Generation And Processing Of Music: Pitch Correction For The Human Voice, Jason Hardy

Computer Science and Computer Engineering Undergraduate Honors Theses

Music is something everyone can enjoy. Shows like American Idol and Dancing with the Stars show us that most everyone, namely more than those who enjoy voting, does enjoy it. Not everyone can make music, and only a special few can make it well. The musically impaired have an ally, though, and it is technology. There are many synthetic ways one may become the dream superstar, especially if they are willing to pay enough. The majority of music generation, processing, and correction software is highly proprietary to their respective owners and carries a high price. Thus, it is difficult in …


A Timer Module For An 8051 Microcontroller, Troy England May 2008

A Timer Module For An 8051 Microcontroller, Troy England

Electrical Engineering Undergraduate Honors Theses

A timer module for an 8051 Microcontroller is designed from the ground up. It could potentially be integrated into a larger 8051 for use in lunar and Martian missions. It follows through a synchronous digital design flow from HDL code through layout verification. The timer shows functionality at 100MHz with some minor glitches.


Benefits Of Leed Designs In Arkansas K-12 Schools, Philip Thrift May 2008

Benefits Of Leed Designs In Arkansas K-12 Schools, Philip Thrift

Mechanical Engineering Undergraduate Honors Theses

This paper provides and evaluation of an existing LEED certified sustainable green building for energy-efficiency, environmental impact, economic value, and occupant health. The new Bethel Middle School located in Bryant, Arkansas was the first LEED (Leadership in Energy and Environmental Design) certified public school building in the state. Based on actual building specifications and validated with the first year's utility bills, a simulation model was used to evaluate various design aspects of the school building. The building's baseline energy usage was compared with numerous energy and environmental scenarios. Results include both environmental and economic assessments. Overall, the study found that …


Aquatic Bacteria Removal Using Carbon Nanotubes, Suvish Melanta May 2008

Aquatic Bacteria Removal Using Carbon Nanotubes, Suvish Melanta

Biological and Agricultural Engineering Undergraduate Honors Theses

The purpose of this project is to explore the functionality of carbon nanotubes as a bacterial removal method, specifically towards water-borne bacterial pathogens in wastewater by utilizing its unique magnetic and bacteria-binding properties. The general protocol set for this research follows five steps: 1) Preparation of wastewater media, 2) preparation of CNT culture, 3) preparation of reaction mixture with CNTs for bacterial binding, 4) magnetic separation of bacteria-bound-CNT clusters and, 5) assessment of supernatant. The CNTs effectively removed bacterial contaminants in the wastewater (10%, v/v) after the sand filtration process from the Paul R. Noland Wastewater Facility at Fayetteville, Arkansas. …


Wayne E. Sabbe Arkansas Soil Fertility Studies 2007, Nathan A. Slaton Apr 2008

Wayne E. Sabbe Arkansas Soil Fertility Studies 2007, Nathan A. Slaton

Arkansas Agricultural Experiment Station Research Series

Rapid technological changes in crop management and production require that the research efforts also be presented in an expeditious manner. The contributions of soil fertility and fertilizers are major production factors in all Arkansas crops. The studies described within will allow producers to compare their practices with the university’s research efforts. Additionally, soil test data and fertilizer sales are presented to allow comparisons among years, crops, and other areas within Arkansas.


Projecting The Economic Impact Of The Fayetteville Shale Play For 2008-2012, Katherine A. Deck Mar 2008

Projecting The Economic Impact Of The Fayetteville Shale Play For 2008-2012, Katherine A. Deck

Publications and Presentations

In 2006, the Center for Business and Economic Research released an economic impact study of the newly developing natural gas industry related to the Fayetteville Shale. The Fayetteville Shale is an unconventional gas reservoir located on the Arkansas side of the Arkoma Basin, ranging in thickness from 50 to 325 feet and ranging in depth from 1,500 to 6,500 feet. That study concluded that from 2005 to 2008, economic output of over $5.5 billion and 9,683 jobs would be generated as a result of investments in the Fayetteville Shale. Those estimates were based on the best information available when the …


Runoff Using A Combined Geographic Information System And Curve Number Approach, Keshia M. Koehn Jan 2008

Runoff Using A Combined Geographic Information System And Curve Number Approach, Keshia M. Koehn

Inquiry: The University of Arkansas Undergraduate Research Journal

Stormwater runoff can transport nutrients, sediments, chemicals, and pathogens to surface water bodies. Managing runoff is crucial to preserving water quality in rapidly developing urban watersheds like Northwest Arkansas. A watershed containing much of the University of Arkansas campus was identified as the target area for this study because stormwater from this location drains into the West Fork of the White River, designated as an impaired water body due to siltation. The project objective was to develop a methodology to test existing stormwater drainage infrastructure, identify potential areas of improvement, and estimate potentially contaminated runoff by combining two widely used …


The Impact Of Severance Taxes On The Arkansas Natural Gas Market, Tammy Lippert Jan 2008

The Impact Of Severance Taxes On The Arkansas Natural Gas Market, Tammy Lippert

Inquiry: The University of Arkansas Undergraduate Research Journal

The recent development of the Fayetteville Shale Play, an unconventional natural gas reservoir in Central and Eastern Arkansas, has created considerable opportunities for the state and its citizens as the industry has made substantial investment in the region. These developments have resulted in thousands of new jobs for Arkansans, billions of dollars in direct and indirect output, and millions in state and local tax revenues. One of the most visible issues in recent state news has been the controversy surrounding the severance tax levied by the state government on the extraction of natural gas. The question at hand has been …


Taking Another Look: Light N-Capture Element Abundances In Metal-Poor Halo Stars, D. Burris, E. Jones, J. Lusk Jan 2008

Taking Another Look: Light N-Capture Element Abundances In Metal-Poor Halo Stars, D. Burris, E. Jones, J. Lusk

Journal of the Arkansas Academy of Science

Elements are produced in stars through a variety of processes; some are well known, others are still the object of active research. The elements Zirconium (Zr) and Yttrium (Y) are produced via neutron capture (ncapture). These elements reside in the mass range where there is uncertainty about the production mechanism at early time. The rapid n-capture process (r-process) was believed to be responsible for the production, but no study (Burris et al 2000, Gilroy et al 1988 and others) has been able to successfully use the r-process to reproduce the abundance signature for elements in this mass range for metal-poor …


Relative Searching Using An Ordered Token List, Anthony Rosequist Jan 2008

Relative Searching Using An Ordered Token List, Anthony Rosequist

Inquiry: The University of Arkansas Undergraduate Research Journal

Many organizations have large amounts of information, such as consumer data, that need to be processed. Traditional searching algorithms only attempt to find exact matches to particular queries. This is undesirable when data are missing, outdated, or inaccurate. Therefore, a new type of search must be developed to locate records that are considered "interesting" to the user. This research paper examines past attempts to solve this problem and explores a new method involving ordered token lists to achieve this goal. The algorithm was developed, implemented, tested, and optimized.


Ionization Rate, Temperature, And Number Density For Breakdown Waves With A Large Current Behind The Shock Front, S. Norman, Mostafa Hemmati, J. King Jan 2008

Ionization Rate, Temperature, And Number Density For Breakdown Waves With A Large Current Behind The Shock Front, S. Norman, Mostafa Hemmati, J. King

Journal of the Arkansas Academy of Science

A three component, one-dimensional, constant velocity, steady-state fluid model is employed to describe the breakdown waves with a current behind the wave front propagating into a neutral gas subjected to an external electric field. Electron gas partial pressure is much larger than that of the other species and therefore is considered to provide the driving force for the wave. The system of equations includes the equations of conservation of mass, momentum, and energy coupled with Poisson’s equation. Inclusion of current behind the wave front in the system of fluid equations also alters the initial boundary conditions and ionization rate. We …


Life Cycle Analysis For The Cultivation And Combustion Of Miscanthus For Biofuel Compared With Natural Gas, Amanda Ashworth, Charles West, Michael Popp, Mireille Montrejaud-Vignoles, Caroline Sablayrolles, Gabrielle Benoit Jan 2008

Life Cycle Analysis For The Cultivation And Combustion Of Miscanthus For Biofuel Compared With Natural Gas, Amanda Ashworth, Charles West, Michael Popp, Mireille Montrejaud-Vignoles, Caroline Sablayrolles, Gabrielle Benoit

Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences

As negative environmental and economic impacts of fossil fuels have escalated, so has the importance of renewable bioenergy crops whose feedstocks are noncompetitive with food supplies. Compared with fossil fuels, use of lignocellulosic feedstocks offers potential for greenhouse gas reduction and highly positive net energy returns because of low input demand and high yields per unit of land area, thus making them advantageous for the emerging biofuel industry. The aim of this study was to simulate environmental impacts of producing a biofuel grass for combustion use based on the inventory of inputs and their effects on eutrophication of surface waters; …


Using Combined Prediction Models To Quantify And Visualize Stormwater Runoff In An Urban Watershed, Keshia Koehn, Cristina Scarlat, Kristofor Brye Jan 2008

Using Combined Prediction Models To Quantify And Visualize Stormwater Runoff In An Urban Watershed, Keshia Koehn, Cristina Scarlat, Kristofor Brye

Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences

Stormwater runoff can transport nutrients, sediments, chemicals, and pathogens to surface waterbodies. Managing runoff is crucial to preserving water quality in rapidly developing urban watersheds like those in Northwest Arkansas. A watershed containing the majority of the University of Arkansas campus was designated as the study area because stormwater from it drains into the West Fork of the White River, designated as an impaired waterbody due to siltation. The project objective was to develop methodology to test existing stormwater drainage infrastructure, identify potential areas of improvement, and estimate potentially contaminated runoff by combining two widely used prediction models. The U.S. …


Using Biosolids To Enhance Phytoremediation Of Oil-Contaminated Soil, Heather N. Markway, Duane C. Wolf, Kaaron J. Davis, Edward E. Gbur Jan 2008

Using Biosolids To Enhance Phytoremediation Of Oil-Contaminated Soil, Heather N. Markway, Duane C. Wolf, Kaaron J. Davis, Edward E. Gbur

Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences

While the plant rhizosphere and associated microbial processes have been shown to amplify the degradation rate of chemical residues in soils, phytoremediation can be a slow process. The objective of this greenhouse study was to determine if the addition of biosolids as an organic soil amendment would enhance growth of plants in oil-contaminated soil and thus potentially increase effectiveness of phytoremediation. Pearl millet (Pennisetum glaucum (L.) R. Br.) or sudangrass (Sorghum sudanense (Piper) Stapf (Piper)) was grown in a Captina silt loam (finesilty, siliceous, mesic Typic Fragiudults) contaminated with 5% crude oil (v/w) and amended with 24 g biosolids/kg soil. …


Resonance Raman Spectroscopy For The Investigation Of Heteroleptic Ruthenium Polypyridine Complexes, Anwar A. Bhuiyan Jan 2008

Resonance Raman Spectroscopy For The Investigation Of Heteroleptic Ruthenium Polypyridine Complexes, Anwar A. Bhuiyan

Journal of the Arkansas Academy of Science

No abstract provided.


Energy Efficient Removal Of Tds From Ro Reject And Cooling Tower Blowdown, Heath Himstedt, Meredith Bruick, Matthew Correnti, Seth Huber, Pettus Kincannon, Mai Sayarath Dec 2007

Energy Efficient Removal Of Tds From Ro Reject And Cooling Tower Blowdown, Heath Himstedt, Meredith Bruick, Matthew Correnti, Seth Huber, Pettus Kincannon, Mai Sayarath

Chemical Engineering Undergraduate Honors Theses

The southwestern United States, specifically the Albuquerque, NM area, was chosen as the target location for implementation of the Project ZERO design due to the volume of electronics manufacturing facilities in the area and the critical need to conserve water. The WERC RO reject sample, believed to originate in chemical mechanical polishing, contains high amounts of silica, trace heavy metals, and salt compounds that would negatively impact water quality if it were discharged into surface waters. Because of the high levels of silica, special precaution must be taken when utilizing membrane or mechanical evaporation technologies due to fouling and scaling …


Water Quality Sampling, Analysis And Annual Load Determinations For Nutrients And Sediment At The Arkansas Highway 45 Bridge On The White River Just Above Beaver Lake, Marc Nelson, Wade Cash, Keith Trost, Jennifer Purtle, J.V. Brahana Jun 2007

Water Quality Sampling, Analysis And Annual Load Determinations For Nutrients And Sediment At The Arkansas Highway 45 Bridge On The White River Just Above Beaver Lake, Marc Nelson, Wade Cash, Keith Trost, Jennifer Purtle, J.V. Brahana

Arkansas Water Resources Center Technical Reports

This report is for water quality sampling, water sample analysis and annual pollutant load calculations at the Arkansas Highway 45 Bridge on the White River for calendar year 2006.


Illinois River 2006, Water Quality Assessment At The Arkansas Highway 59 Bridge, Marc A. Nelson, Wade Cash, Keith Trost, Jennifer Purtle Jun 2007

Illinois River 2006, Water Quality Assessment At The Arkansas Highway 59 Bridge, Marc A. Nelson, Wade Cash, Keith Trost, Jennifer Purtle

Arkansas Water Resources Center Technical Reports

Automatic water sampler and a U. S. Geological Survey gauging station were established in 1995 on the main stem of the Illinois River at the Arkansas Highway 59 Bridge. Since that time, continuous stage and discharge measurements and water quality sampling have been used to determine pollutant concentrations and loads in the Arkansas portion of the Illinois River. This report represents the results from the measurement and sampling by the Arkansas Water Resources Center -Water Quality Lab for January 1, 2006 to December 31, 2006.


Water Quality Sampling, Analysis And Annual Load Determinations For Tss, Nitrogen And Phosphorus At The Ballard Creek Near Arkansas/Oklahoma Line, Marc Nelson, Wade Cash, Keith Trost, Jennifer Purtle, J.V. Brahana, Ken Steele Jun 2007

Water Quality Sampling, Analysis And Annual Load Determinations For Tss, Nitrogen And Phosphorus At The Ballard Creek Near Arkansas/Oklahoma Line, Marc Nelson, Wade Cash, Keith Trost, Jennifer Purtle, J.V. Brahana, Ken Steele

Arkansas Water Resources Center Technical Reports

The Illinois River Basin has experienced water quality impairment from non-point source pollution for many years. This fact was well documented in the State of Arkansas' Water Quality Assessment report, the Soil Conservation Service River Basin Study, and several University of Arkansas studies. Thirty-seven sub-watersheds have been identified by the SCS in the Arkansas portion of the Illinois River basin. In the Arkansas portion of the Basin, the Illinois River, Evansville Creek, Baron Fork, Cincinnati Creek, Muddy Fork, Moores Creek, Clear Creek, Osage Creek and Flint Creek were all classified as not supporting their designated use as primary contact recreation …


Continuation Of Water Quality Monitoring Of The Osage Creek Above The Highway 112 Bridge Near Cave Springs, Arkansas, Marc Nelson, Luanna Diffin May 2007

Continuation Of Water Quality Monitoring Of The Osage Creek Above The Highway 112 Bridge Near Cave Springs, Arkansas, Marc Nelson, Luanna Diffin

Arkansas Water Resources Center Technical Reports

The City of Rogers is one of the fastest growing communities in Arkansas. Located in Northwest Arkansas, Rogers lies in two primary watersheds; the Illinois River Watershed and Beaver Lake Watershed. The Illinois River Watershed receives municipal wastewater discharge from most of the metropolitan communities in Northwest Arkansas, along with nonpoint source urban and agricultural runoff. The Illinois River originates in Arkansas and flows west into Oklahoma where it is classified as a scenic river. The river has been a source of interstate disputes for a number of years. A federal interstate compact commission was established to mediate these disputes, …