Digital Commons Network^™

Evaluation Of Rice Hulls As A Lignocellulosic Substitute In Wood Plastic Composites, P. Jack Bourne

Inquiry: The University of Arkansas Undergraduate Research Journal

Rising raw material costs and shortage of woody materials necessitate alternative sources for lignocellulosic material in wood plastic composites (WPC). This study was conducted to evaluate rice hull (RH), an agricultural residue, as a cellulosic substitute in WPC. Samples were fabricated with approximately 4% zinc stearate, 48% high-density polyethylene obtained from recycled plastics and 48% lignocellulosic material by mass. The composition of the lignocellulosic material was changed from 0 to 100% RH at 20% increments while the remainder was wood flour. The extruded sampled were tested for mechanical properties such as specific gravity, water absorption, linear coefficients of thermal expansion, …

Effect Of Seeding Materials And Mixing Strength On Struvite Precipitation, Jun Wang, Joel Gerard Burken, Xiaoqi Zhang

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Struvite Precipitation Has Increasing Interest as a Technology for Removing and Recovering Phosphorus from Wastewater Streams. Many Chemical Factors Have Been Studied, Such as Optimum PH Values and Component-Ion Molar Ratios, Yet, Understanding of Physical Aspects is Lacking. Two Physical Parameters Were Tested: (1) Seeding Material Addition and (2) Mixing. Objectives Were to Evaluate Three Seeding Materials and to Optimize Mixing Conditions for Struvite-Crystal Precipitation, Growth, and Subsequent Sedimentation. Results Confirm that Mixing Strength and Proper Seeding Materials Increase Crystal Size and Improve Settleability. for Unseeded Solutions, Optimum Phosphorus Removal Was Achieved at a Mixing Strength of G = 76 …

Perchlorate Toxicity And Risk Assessment, David R. Mattie, Joan Strawson, Jay Zhao

United States Air Force: Publications

Ammonium perchlorate is the oxidizer ingredient in solid propellant mixtures for rockets, missiles and munitions such as Titan, Minuteman, Peacekeeper, Hawk, Polaris and the Space Shuttle. Perchlorate salts may also be used in medicine, matches, munitions and pyrotechnics (illuminating and signaling flares, colored and white smoke generators, tracers, incendiary delays, fuses, photo-flash compounds and fireworks). Perchlorate is also found in lubricating oils, finished leather, fabric fixer, dyes, electroplating, aluminum refining, manufacture of rubber, paint and enamel production, as an additive in cattle feed, in magnesium batteries and as a component of automobile air bag inflators.'

In Vivo Laparoscopic Robotics, Mark E. Rentschler, Stephen R. Platt, Jason Dumpert, Shane M. Farritor, Dmitry Oleynikov

Department of Mechanical and Materials Engineering: Faculty Publications

Robotic laparoscopic surgery is evolving to include in vivo robotic assistants. The impetus for the development of this technology is to provide surgeons with additional viewpoints and unconstrained manipulators that improve safety and reduce patient trauma. A family of these robots have been developed to provide vision and task assistance. Fixed-base and mobile robots have been designed and tested in animal models with much success. A cholecystectomy, prostatectomy, and nephrectomy have all been performed with the assistance of these robots. These early successful tests show how in vivo laparoscopic robotics may be part of the next advancement in surgical technology.

Assessing Effects Of Alternative Agricultural Practices On Wildlife Habitat In Iowa, Usa, Mary Santelmann, Kathryn Freemark, Jean Sifneos, Denis White

United States Environmental Protection Agency: Publications

A habitat-change model was used to compare past, present, and future land cover and management practices to assess potential impacts of alternative agricultural practices on wildlife in two agricultural watersheds, Walnut Creek and Buck Creek, in central Iowa, USA. This approach required a habitat map for each scenario based on soil type and land cover, a list of resident species, and an estimate of the suitability of each of 26 habitat classes for every species. Impact on wildlife was calculated from median percent change in habitat area relative to the present. Habitat classes with the highest species richness for native …

Mode Of Action In Relevance Of Rodent Liver Tumors To Human Cancer Risk, Michael P. Holsapple, Henri C. Pitot, Samuel H. Cohen, Alan R. Boobis, James E. Klaunig, Timothy Pastoor, Vicki L. Dellarco, Yvonne P. Dragan

United States Environmental Protection Agency: Publications

Hazard identification and risk assessment paradigms depend on the presumption of the similarity of rodents to humans, yet species specific responses, and the extrapolation of high-dose effects to lowdose exposures can affect the estimation of human risk from rodent data. As a consequence, a human relevance framework concept was developed by the International Programme on Chemical Safety (IPCS) and International Life Sciences Institute (ILSI) Risk Science Institute (RSI) with the central tenet being the identification of a mode of action (MOA). To perform a MOA analysis, the key biochemical, cellular, and molecular events need to first be established, and the …

The Fathead Minnow In Aquatic Toxicology: Past, Present And Future, Gerald T. Ankley, Daniel L. Villeneuve

United States Environmental Protection Agency: Publications

This paper reviews the roles of the fathead minnow (Pimephales promelas) as a small fish model in the field of aquatic toxicology. The species has been (and is) extensively used both for regulatory testing and research, especially in North America. For example, tests with the fathead minnow, ranging from 48-h lethality through partial and full life-cycle assays, are routinely used for regulatory programs aimed at assessing potential risks of new chemicals such as high-production volume materials and pesticides, as well as impacts of complex mixtures like effluents. The species also has been used for a wide variety of …

"Introduction" To Advanced Magnetic Nanostructures, David J. Sellmyer, Ralph Skomski

Materials Research Science and Engineering Center: Faculty Publications

The nanostructures considered here are magnetic and characterized by structural length scales ranging from a few interatomic distances to about one micrometer. The basic length unit is the nanometer (1 nm = 10^–3 μm = 10^–9 m), corresponding to about four interatomic Fe-Fe distances. Magnetic nanostructures pose experimental challenges, exhibit interesting physical phenomena, and have many present or potential applications. An important aspect is that structural lengths affect, but only partly determine, the magnetic length scales encountered in the structures. Examples are domains in semihard nanoparticles, where both the domain size and the domain-wall thickness may be smaller …

Human Transcriptome Corresponding To Human Oocytes And Use Of Said Genes Or The Corresponding Polypeptides To Trans-Differentiate Somatic Cells, Jose Bernardo Cibelli, Arif Murat Kocabas, Bing Lim, Hasan H. Otu

Department of Electrical and Computer Engineering: Faculty Publications

The identification of 101 genes upregulated or differentially expressed by mature human oocytes is provided herein. These genes and the corresponding gene products will facilitate a greater understanding of oogenesis, folliculogenesis, fertilization, and embryonic development. In addition these genes and the corresponding gene products can be used to effect dedifferentiation and/or transdifferentiation of desired somatic cells. The resultant dedifferentiated cells and somatic cells derived therefrom can be used in cell therapies such as in the treatment of cancer, autoimmunity, and other diseases wherein specific types of cells such as hematopoietic cells may be depleted because of the underlying disease or …

A Common Component-Based Software Architecture For Military And Commercial Pc-Based Virtual Simulation, Joshua Lewis

Electronic Theses and Dissertations

Commercially available military-themed virtual simulations have been developed and sold for entertainment since the beginning of the personal computing era. There exists an intense interest by various branches of the military to leverage the technological advances of the personal computing and video game industries to provide low cost military training. By nature of the content of the commercial military-themed virtual simulations, a large overlap has grown between the interests, resources, standards, and technology of the computer entertainment industry and military training branches. This research attempts to identify these commonalities with the purpose of systematically designing and evaluating a common component-based …

User-Centered Virtual Environment Assessment And Design For Cognitive Rehabilitation Applications, Cali Fidopiastis

Electronic Theses and Dissertations

Virtual environment (VE) design for cognitive rehabilitation necessitates a new methodology to ensure the validity of the resulting rehabilitation assessment. We propose that benchmarking the VE system technology utilizing a user-centered approach should precede the VE construction. Further, user performance baselines should be measured throughout testing as a control for adaptive effects that may confound the metrics chosen to evaluate the rehabilitation treatment. To support these claims we present data obtained from two modules of a user-centered head-mounted display (HMD) assessment battery, specifically resolution visual acuity and stereoacuity. Resolution visual acuity and stereoacuity assessments provide information about the image quality …

A Holistic Usability Framework For Distributed Simulation Systems, Jeffrey Dawson

Electronic Theses and Dissertations

This dissertation develops a holistic usability framework for distributed simulation systems (DSSs). The framework is developed considering relevant research in human-computer interaction, computer science, technical writing, engineering, management, and psychology. The methodology used consists of three steps: (1) framework development, (2) surveys of users to validate and refine the framework, and to determine attribute weights, and (3) application of the framework to two real-world systems. The concept of a holistic usability framework for DSSs arose during a project to improve the usability of the Virtual Test Bed, a prototypical DSS, and the framework is partly a result of that project. …

Automated Scenario Generation System In A Simulation, Hajime Tomizawa

Electronic Theses and Dissertations

Developing training scenarios that induce a trainee to utilize specific skills is one of the facets of simulation-based training that requires significant effort. Simulation-based training systems have become more complex in recent years. Because of this added complexity, the amount of effort required to generate and maintain training scenarios has increased. This thesis describes an investigation into automating the scenario generation process. The Automated Scenario Generation System (ASGS) generates expected action flow as contexts in chronological order from several events and tasks with estimated time for the entire training mission. When the training objectives and conditions are defined, the ASGS …

Examining Route Diversion And Multiple Ramp Metering Strategies For Reducing Real-Time Crash Risk On Urban Freeways, Vikash Gayah

Electronic Theses and Dissertations

Recent research at the University of Central Florida addressing crashes on Interstate-4 in Orlando, Florida has led to the creation of new statistical models capable of calculating the crash risk on the freeway (Abdel-Aty et al., 2004; 2005, Pande and Abdel-Aty, 2006). These models yield the rear-end and lane-change crash risk along the freeway in real-time by using static information at various locations along the freeway as well as real-time traffic data that is obtained from the roadway. Because these models use the real-time traffic data, they are capable of calculating the respective crash risk values as the traffic flow …

Cognitive Training Transfer Using A Personal Computer-Based Game:A Close Quarters Battle Case Study, Michael Woodman

Electronic Theses and Dissertations

Developers of Commercial off the Shelf (COTS) gaming software are making remarkable strides in increasing the realism of their software. This realism has caught the attention of the training community, which has traditionally sought system and operational replication in training systems such as flight simulators. Since games are designed and marketed for entertainment and not designed for training of tasks, questions exist about the effectiveness of games as a training system in achieving the desired transfer of skills to the actual environment. Numerous studies over the past ten years have documented that PC-based simulation training environments can offer effective training …

Fundamental Aspects Of Regenerative Cerium Oxide Nanoparticles And Their Applications In Nanobiotechnology, Swanand Patil

Electronic Theses and Dissertations

Cerium oxide has been used extensively for various applications over the past two decades. The use of cerium oxide nanoparticles is beneficial in present applications and can open avenues for future applications. The present study utilizes the microemulsion technique to synthesize uniformly distributed cerium oxide nanoparticles. The same technique was also used to synthesize cerium oxide nanoparticles doped with trivalent elements (La and Nd). The fundamental study of cerium oxide nanoparticles identified variations in properties as a function of particle size and also due to doping with trivalent elements (La and Nd). It was found that the lattice parameter of …

Modeling Autonomous Agents In Military Simulations, Varol Kaptan

Electronic Theses and Dissertations

Simulation is an important tool for prediction and assessment of the behavior of complex systems and situations. The importance of simulation has increased tremendously during the last few decades, mainly because the rapid pace of development in the field of electronics has turned the computer from a costly and obscure piece of equipment to a cheap ubiquitous tool which is now an integral part of our daily lives. While such technological improvements make it easier to analyze well-understood deterministic systems, increase in speed and storage capacity alone are not enough when simulating situations where human beings and their behavior are …

Characterization Of Critical Network Components Of Coupled Oscillators, Gregory Holifield

Electronic Theses and Dissertations

This dissertation analyzes the fundamental limits for the determination of the network structure of loosely coupled oscillators based on observing the behavior of the network, specifically, node synchronization. The determination of the requisite characteristics and underlying behaviors necessary for the application of a theoretical mechanism for determining the underlying network topology in a network of loosely coupled natural oscillators are the desired outcome. To that end, this effort defines an analytical framework where key components of networks of coupled oscillators are isolated in order to determine the relationships between the various components. The relationship between the number of nodes in …

Parameter Estimation In Linear Regression, Kati Ollikainen

Electronic Theses and Dissertations

Today increasing amounts of data are available for analysis purposes and often times for resource allocation. One method for analysis is linear regression which utilizes the least squares estimation technique to estimate a model's parameters. This research investigated, from a user's perspective, the ability of linear regression to estimate the parameters' confidence intervals at the usual 95% level for medium sized data sets. A controlled environment using simulation with known data characteristics (clean data, bias and or multicollinearity present) was used to show underlying problems exist with confidence intervals not including the true parameter (even though the variable was selected). …

A Dynamic Heuristic For The Stochastic Unrelated Parallel Machine Scheduling Problem, Jean-Paul Arnaout, Ghaith Rabadi, Ji Hyon Mun

Engineering Management & Systems Engineering Faculty Publications

This paper addresses the problem of batch scheduling in an unrelated parallel machine environment with sequence dependent setup times and an objective of minimizing the total weighted mean completion time. The jobs' processing times and setup times are stochastic for better depiction of the real world. This is a NP-hard problem and in this paper, new heuristics are developed and compared to existing ones using simulation. The results and analysis obtained from the computational experiments proved the superiority of the proposed algorithm PMWP over the other algorithms presented.

Kentucky Water Resources Research Institute Annual Technical Report Fy 2005, Kentucky Water Resources Research Institute, University Of Kentucky

KWRRI Annual Technical Reports (USGS’s 104b Grant Program)

The 2005 Annual Technical Report for Kentucky consolidates reporting requirements of the Section 104(b) base grant award in a single technical report that includes: 1) a synopsis of each research project supported during the period, 2) related reports and publications, 3) a description of information transfer activities, 4) a summary of student support during the reporting period, and 5) notable achievements and awards during the year.

Kentucky Traffic Collision Facts 2006 Report, Kentucky Transportation Center, Kentucky State Police

Kentucky Transportation Center Research Report

KENTUCKY’S TRAFFIC COLLISION FACTS report for 2006 is based on collision reports submitted to the Kentucky State Police Records Branch. As required by Kentucky Revised Statutes 189.635, “every law enforcement agency whose officers investigate a vehicle accident of which a report must be made...shall file a report of the accident...within ten days after investigation of the accident upon forms supplied by the bureau.” The stated purpose of this requirement is to utilize data on traffic collisions for such purposes as will improve the traffic safety program in the Commonwealth. Data contained in this report are based solely on the observations …

Computational Sciences: At The Intersection Of Science And Engineering--Case Study For Academic And Research Programs, Menas Kafatos, Peter Becker, Zafer Boybeyi̇

Turkish Journal of Electrical Engineering and Computer Sciences

No abstract provided.

The Role Of Energy Pipelines And Research In The United States, Cheryl J. Trench, Thomas O. Miesner

United States Department of Transportation: Publications

Energy from oil and natural gas is essential, and will continue to be essential, to all facets of our daily lives. It fuels most of our transportation needs, heats our homes, schools, offices and shops, and even generates a share of our electricity. Oil and natural gas together supply approximately two-thirds of the U.S. energy needs.

Crude oil and natural gas are generally produced in regions located far from consumption centers. This means crude oil must be moved to refineries, and refined products and natural gas must be moved from producing regions to consumption centers.

The U.S. pipeline infrastructure is …

Evolution Of The Snow Area Index Of The Subarctic Snowpack In Central Alaska Over A Whole Season. Consequences For The Air To Snow Transfer Of Pollutants, A.S. Taillandier, F. Domine, W.R. Simpson, M. Sturm, T.A. Douglas, K Severin

United States Army: Publications

The detailed physical characteristics of the subarctic snowpack must be known to quantify the exchange of adsorbed pollutants between the atmosphere and the snow cover. For the first time, the combined evolutions of specific surface area (SSA), snow stratigraphy, temperature, and density were monitored throughout winter in central Alaska. We define the snow area index (SAI) as the vertically integrated surface area of snow crystals, and this variable is used to quantify pollutants’ adsorption. Intense metamorphism generated by strong temperature gradients formed a thick depth hoar layer with low SSA (90 cm² g^-1) and density (200 kg …

Research Needs In Water Resources And Environment: A Panel Discussion, Otto J. Helweg, Joseph Orlins, Dale Bucks, Regan Murray, David Trueman, Raymond Walton

United States Environmental Protection Agency: Publications

Practicing engineers sometimes criticize researchers for answering questions that no one is asking, or at least for conducting research on questions of personal interest or in areas that funding agencies think are important. Although such research has a place in the overall picture of things, it is instructive to consider the practical issues that engineers in the field face. The fields of water resources and environment are very broad, and only a small number of research users could be included on the panel seated by the Education and Research Council at the 2004 World Water and Environmental Resources Congress. One …

A View-Based Deformation Tool-Kit, Master's Thesis, August 2006, Nisha Sudarsanam

All Computer Science and Engineering Research

Camera manipulation is a hard problem since a graphics camera is defined by specifying 11 independent parameters. Manipulating such a high-dimensional space to accomplish specific tasks is difficult and requires a certain amount of expertise. We present an intuitive interface that allows novice users to perform camera operations in terms of the change they want see in the image. In addition to developing a natural means for camera interaction, our system also includes a novel interface for viewing and organizing previously saved views. When exploring complex 3D data-sets a single view is not sufficient. Instead, a composite view built from …

A Thesis On Sketch-Based Techniques For Mesh Deformation And Editing, Raquel Bujans

All Computer Science and Engineering Research

The goal of this research is to develop new and more intuitive ways for editing a mesh from a static camera angle. I present two ways to edit a mesh via a simple sketching system. The first method is a gray-scale editor which allows the user to specify a fall off function for the region being deformed. The second method is a profile editor in which the user can re-sketch a mesh’s profile. Lastly, the types of edits possible will be discussed and our results will be presented.

Use Of Gene Expression Profiling And Machine Learning To Understand And Predict Primary Graft Dysfunction, Monika Ray, Sekhar Dharmarajan, Johannes Freudenberg, Weixiong Zhang, Alexander G. Patterson

All Computer Science and Engineering Research

No abstract provided.

Force Measurements On A Flapping And Pitching Wing At Low Reynolds Numbers, Kakkattukuzhy M. Isaac, Anthony Colozza, Jessica Rolwes

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Force measurements from experiments conducted in water on a flapping-and-pitching thin flat plate wing of semi-elliptic planform at low Reynolds numbers are reported. Time varying force data, measured using a force transducer, provide a means to understand the mechanisms that lead to enhanced performance observed in insect flight compared to fixed wing aerodynamics. Experimental uncertainties associated with low level (∼1N) fluid dynamic force measurements on flapping-and-pitching wings are addressed. a previously proposed pitching mode in which the leading edge and trailing edge switch roles to allow using cambered airfoils has been shown to be viable and may have advantages over …