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Viscoelastic Depinning Of Driven Systems: Mean-Field Plastic Scallops, M. Cristina Marchetti, Alan Middleton, Thomas Prellberg

Physics - All Scholarship

We have investigated the mean field dynamics of an overdamped viscoelastic medium driven through quenched disorder. The model introduced incorporates coexistence of pinned and sliding degrees of freedom and can exhibit continuous elastic depinning or first order hysteretic depinning. Numerical simulations indicate mean field instabilities that correspond to macroscopic stick-slip events and lead to premature switching. The model is relevant for the dynamics of driven vortex arrays in superconductors and other extended disordered systems.

Nanocomposite Copt:C Films For Extremely High-Density Recording, M. Yu, Yi Liu, A. Moser, D. Weller, David J. Sellmyer

David Sellmyer Publications

Nanocomposite CoPt:C films were investigated as potential media for extremely high-density recording. An annealing temperature of over 600 °C is necessary to form nanocomposite CoPt:C films consisting of C matrix and fct CoPt nanocrystallites with grain sizes of 8–20 nm and coercivities of 3–12 kOe. Coercivity and grain size increase with increasing annealing temperature and decreasing C concentration and they are insensitive to film thickness. The average activation volumes are about 0.9×10^-18 cm³. The properties of these nanocomposite CoPt:C films can be tailored to satisfy the thermal stability, coercivity, and media noise requirements for extremely high-density recording.

High-Order Derivative Spectroscopy For Selecting Spectral Regions And Channels For Remote Sensing Algorithm Development, Charles R. Bostater

Ocean Engineering and Marine Sciences Faculty Publications

A remote sensing reflectance model, which describes the transfer of irradiant light within a plant canopy or water column has previously been used to simulate the nadir viewing reflectance of vegetation canopies and leaves under solar induced or an artificial light ur'2 and the water surface reflectance3' Wavelength dependent features such as canopy reflectance leafabsorption and canopy bottom reflectance as well as water absorption and water bottom reflectance have been used to simulate or generate synthetic canopy and water surface reflectance signatures3' ' This paper describes how derivative spectroscopy can be utilized to invert the synthetic or modeled as well …

Book Review: Mathematical Reflections By Peter Hilton, Derek Holton And Jean Pedersen, Ladnor Geissinger

Humanistic Mathematics Network Journal

No abstract provided.

Investigating Ground And Surface Water In The Republican River Basin Of Nebraska Using Water Chemistry And Environmental Isotopes, Jennifer J. Schellpeper

School of Natural Resources: Dissertations, Theses, and Student Research

Recent legal battles concerning water use initiated an investigation of the stream/aquifer relationships in the Republican River Basin located in southwest Nebraska. Ground and surface water was analyzed for tritium, deuterium, ¹⁸O, and major ions. Temperature, pH, conductivity and alkalinity were determined on-site. Samples were collected during 1997 and 1998 from irrigation wells throughout the entire basin. Localized interactions between groundwater and surface water were examined during twenty-four hour pump tests performed on the irrigation wells screened in the alluvium along the river valley and its tributaries. These data show there are differences between the ground and surface waters …

Characterizations Of Classes Of Programs By Three-Valued Operators, Anthony K. Seda, Pascal Hitzler

Computer Science and Engineering Faculty Publications

Several important classes of normal logic programs, including the classes of acyclic, acceptable, and locally hierarchical programs, have the property that every program in the class has a unique two-valued supported model. In this paper, we call such classes unique supported model classes. We analyse and characterize these classes by means of operators on three-valued logics. Our studies will motivate the definition of a larger unique supported model class which we call the class of Phi-accessible programs. Finally, we show that the class of Phi -accessible programs is computationally adequate in that every partial recursive function can be implemented by …

Network Security Versus Network Connectivity: A Framework For Addressing The Issues Facing The Air Force Medical Community, Franklin E. Cunningham Jr.

Theses and Dissertations

The Air Force has instituted Barrier Reef to protect its networks. The Air Force medical community operates network connections that are incompatible with Barrier Reef. To overcome this problem, OASD(HA) directed the Tri-Service Management Program Office (TIMPO) to develop an architecture that protects all military health systems and allows them to link with all three services and outside partners. This research studied the underlying networking issues and formed a framework based on data from network experts from the Air Force's medical centers and their base network organizations. The findings were compared TIMPO and a composite framework was developed that more …

On-Line Bayesian Tree-Structured Transformation Of Hidden Markov Models For Speaker Adaptation, Shaojun Wang, Yunxin Zhao

Kno.e.sis Publications

This paper presents a new recursive Bayesian learning approach for transformation parameter estimation in speaker adaptation. Our goal is to incrementally transform (or adapt) the entire set of HMM parameters for a new speaker or new acoustic enviroment from a small amount of adaptation data. By establishing a clustering tree of HMM Gaussian mixture components, the finest affine transformation parameters for individual HMM Gaussian mixture components can be dynamically searched. The on-line Bayesian learning technique proposed in our recent work is used for recursive maximum a posteriori estimation of affine transformation parameters. Speaker adaptation experiments using a 26-letter English alphabet …

Trace-Level Determination Of Fluorescently Labeled Phenoxy Acid Herbicides And The Study Of Their Crop Uptake And Soil Accumulation, Noura Saeed Al Nuaimi

Theses

A challenging problem facing the determination of phenoxy acid herbicides in samples is their low UV absorptivity and the interference associated with the matrix in which these analytes exist. This thesis is concerned with improving the detection limits of this group of herbicid as well as reduce or eliminate interference associated with the sample matrix.

Native phenoxy acid herbicides could be analyzed by high performance liquid chromatography (HPLC) with ultraviolet detection. Phenoxy herbicides were analyzed by HPLC employing a gradient conditions that allowed baseline resolution of all analytes used in this study in approximately 20 min. However, the average detection …

Experimental Evaluation Of Design Tradeoff In Specialized Virtual Machine For Multimedia Traffic In Active Networks, Sheng-Yih Wang, Bharat Bhargava

Department of Computer Science Technical Reports

No abstract provided.

Calibration, Installation Techniques, And Initial Measurements For Vertical Resistivity Probes Used In Hydrogeologic Investigations, Jeffrey Mark Groncki

Masters Theses

Vertical Resistivity Probes (VRPs) are being increasingly used in a variety of applications where detailed vertical resistivity information in both the vadose and saturated zones is needed. All the different possible array types and spacings must be calibrated for the effect of the 2" (outer diameter) insulating PVC cylinder on which the electrodes are mounted. Apparent resistivities must be corrected by calibration factors. Varying the installation parameters greatly influences the measured apparent resistivity because of the disturbed annulus and the composition of the backfill materials. Bentonite slurry is necessary for the installations to keep the electrodes in good contact with …

A Numerical Simulation Of A Carbon Black Suspension Cell Via A Time-Reversed, Double Layer Compute Algorithm, Gregg T. Anderson

Theses and Dissertations

A numerical simulation of a carbon black suspension cell is explored which models a laser-induced plasma within a liquid ethanol medium of approximately 1 mm thickness. The simulation model assumes a laser pulse with a pulse width of approximately 9 nsecs propagating in the left-to-right direction striking the front surface of the medium and focusing to a spot within the liquid volume. When the energy density within a given irradiated volume is sufficiently high, it ignites the carbon particles and generates a large number of free electrons, i.e., a plasma. The plasma couples with the in-coming laser energy on a …

Measuring Information Quality Of Web Site: Development Of Instrument, P. Katerattanakul, Keng Siau

Research Collection School Of Computing and Information Systems

Web sites have been extensively used to provide information to consumers. While practitioners and researchers have proposed different criteria for effective Web site design based on common sense, intuition, and rules-ofthumb, effective Web site design focusing on the quality of the information it provides has rarely been studied. In this research, we propose a framework and develop an instrument to measure the information quality of individual or personal Web sites. The theoretical foundation of this research is the information quality framework. The proposed framework and instrument were tested in an individual or personal Web site context.

Information System Incidents: The Development Of A Damage Assessment Model, Mark D. Horony

Theses and Dissertations

Information system (IS) incidents are on the rise. With low manning and undertrained information security specialists it is difficult for organizations to stop IS incidents from occurring. Once an incident has occurred it is the IS manager's responsibility to ensure that a full and accurate damage assessment has been accomplished. However, most IS managers lack the necessary tools to assess the damage from an incident. This exploratory thesis developed an IS incident damage assessment model (DAM) that can be part of the IS manager's tool kit. During the development of the model, it became apparent that the model was supported …

Aes Multi-Layer Structural Analysis Of Si Based Anodic Porous Alumina Films And Studies On Its Formation Mechanism, Jun-Hui Wu, Jian-Ping Zou, Qing Zhu, Xi-Mao Bao

Journal of Electrochemistry

400 nm aluminum films were deposited onto a p-type, 0.5 Ω·cm,〈100〉oriented silicon wafers using electron beam evaporation technique. Then, the wafers was immersed in 15 wt% H₂SO₄ for porous-type over-anodization under a constant voltage of DC 60V. During the anodization,the temperature of the electrolyte was maintained at 0 ℃. The obtained samples were investigated by means of transmission electron microscopy, scanning electron microscopy, and AES depth profile for multi-layer structural information. In addition, the basic anodic formation mechanism of the Si-based aluminum films was brielfly discussed.

Electrochemical Studies Of Metal Complexes In Solution, Ye-Xiang Tong, Bei-Sheng Kang, Qi-Qin Yang

Journal of Electrochemistry

The prospectus of electrochemical studies of metal complexes in solution have been introduced as a background of our research work. The electrochemical behaviors of the metal complexes and clusters have been investigated by many kinds of electrochemical methods. The content includes the standard electrode potential and the related equilibrium constant, electrochemical kinetics and the related behavior of structure, electrocatalysis and electrosynthesis of metal complexes. The electrode reaction mechanisms of the complexes have been approached. The methods for measuring some thermodynamic and kinetic parameters of the complexes are also given. Electrochemical studies would provid many kinds of important information for studying …

Electro-Oxidation Of Phenol On Sno2/Ti Electrodes Prepared By Thermal Oxidation, Qing-Song Zhang, Hui-Huang Wu

Journal of Electrochemistry

A SnO₂/Ti electrode prepared by thermal oxidation was used as the anode for galvanostatic electrolysis in acidic solution containing phenol, the time-dependances of phenol concentration, chemical oxygen demand in solution(COD) and instantaneous current efficiency were determined during electrolysis. The results show that with the SnO₂/Ti anode instead of Pt, the COD significantly decreases at the same charge passage, and average current efficiency of oxidation increases by three times. The mechanism for phenol oxidation at two electrodes was discussed.

Rkky Interactions Between Nanomagnets Of Arbitrary Shape, Ralph Skomski

Ralph Skomski Publications

The RKKY interaction between well-separated magnetic particles in a nonmagnetic metallic matrix is calculated. It turns out that the net interaction can be mapped onto an RKKY interaction between two point-like effective moments. The effective moments exhibit a strongly oscillating dependence on the particle's size, shape, and orientation, but their magnitudes are governed by scaling laws. As a rule, magnetostatic interactions tend to suppress the RKKY effect in particles larger than about 1 nm. Surface roughness leaves the effective-moment picture unaltered but tends to yield a moderate reduction of the effective moments. The results are discussed in the context of …

Structural And Magnetic Properties Of Fept:Sio2 Granular Thin Films, C.P. Luo, David J. Sellmyer

David Sellmyer Publications

Nanocomposite FePt:SiO₂ films have been fabricated by annealing the as-deposited FePt/SiO₂ multilayers at temperatures from 450 to 650 °C. These films consist of high-anisotropy tetragonal L1₀ FePt particles embedded in a SiO₂ matrix. The structural and magnetic properties of these films were investigated. We have found that coercivity and grain size are highly dependent on the annealing temperature and SiO₂ concentration. Films with coercivities in the range from 2 to 8 kOe and grain sizes of 10 nm or less were obtained. These films have considerable potential as high-density magnetic recording media.

Mental Models For Introductory Csc Concepts, Jennifer J. Wheeler, Erika Rogers

Computer Science and Software Engineering

If is hypothesized that the development of mental models for a concept can lead to improved learning. The purpose of this paper is to identify, quantify, and analyze the mental models of students beginning to program in the UNIX environment. By focusing on 4 basic concept, this study abstracts current mental models from students and hypothesizes ways of improving these models. Ultimately, the results of the study will be incorporated into the design and implementation of a multimedia tutor. This tutor will attempt to teach people how to develop mental models in order to improve their learning.

Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, Volume 15, Number 9, November 1999, College Of Engineering And Computer Science, Wright State University

BITs and PCs Newsletter

A fourteen page newsletter created by the Wright State University College of Engineering and Computer Science that addresses the current affairs of the college.

A Near-Surface Microstructure Sensor System Used During Toga Coare. Part Ii: Turbulence Measurements, Alexander Soloviev, Roger Lukas, Peter Hacker, H. Schoeberlein, M. Baker, A. Arjannikov

Marine & Environmental Sciences Faculty Articles

New techniques developed for near-surface turbulence measurements during the Tropical Ocean Global Atmosphere (TOGA) Coupled Ocean–Atmosphere Response Experiment (COARE) employ a difference in spatial scales of turbulence and surface waves. According to this approach, high relative speed of the measurements provides separation of the turbulence and surface wave signals. During the TOGA COARE field studies, highresolution probes of pressure, temperature, conductivity, fluctuation velocity, and acceleration were mounted on the bow of the vessel at a 1.7-m depth in an undisturbed region ahead of the moving vessel. The localization in narrow frequency bands of the vibrations of the bow sensors allows …

Student Fact Book, Fall 1999, Twenty Third Annual Edition November 1999, Wright State University, Office Of Student Information Systems, Wright State University

Wright State University Student Fact Books

The student fact book has general demographic information on all students enrolled at Wright State University for Fall Quarter, 1999.

Slow-Binding Inhibition Of The Aminopeptidase From Aeromonas Proteolytica By Peptide Thiols: Synthesis And Spectroscopic Characterization, Kristi M. Huntington, David L. Bienvenue, Yaoming Wei, Brian Bennett, Richard C. Holz, Dehua Pei

Physics Faculty Research and Publications

Peptide-derived thiols of the general structure N-mercaptoacyl-leucyl-p-nitroanilide (1a−c) were synthesized and found to be potent, slow-binding inhibitors of the aminopeptidase from Aeromonas proteolytica (AAP). The overall potencies (K_I*) of these inhibitors against AAP range from 2.5 to 57 nM exceeding that of the natural product bestatin and approaching that of amastatin. The corresponding alcohols (2a−b) are simple competitive inhibitors of much lower potencies (K_I = 23 and 360 μM). These data suggest that the free thiols are involved in the formation of the E·I …

Performance Of The Cleo Iii Lif-Tea Ring Imaging Cherenkov Detector In A High Energy Muon Beam, Raymond Mountain, Marina Artuso, R. Ayad, F. Azfar

Physics - All Scholarship

The CLEO III Ring Imaging Cherenkov detector uses LiF radiators to generate Cherenkov photons which are then detected by proportional wire chambers using a mixture of CH$_4$ and TEA gases. The first two photon detector modules which were constructed, were taken to Fermilab and tested in a beam dump that provided high momentum muons. We report on results using both plane and "sawtooth" shaped radiators. Specifically, we discuss the number of photoelectrons observed per ring and the angular resolution. The particle separation ability is shown to be sufficient for the physics of CLEO III.

Computational Study Of Molecular Hydrogen In Zeolite Na-A. I. Potential Energy Surfaces And Thermodynamic Separation Factors For Ortho And Para Hydrogen, Cherry-Rose K. Anderson , '95, D. F. Coker, J. Eckert, Amy Lisa Graves

Physics & Astronomy Faculty Works

We simulate H-2 adsorbed within zeolite Na-A. We use a block Lanczos procedure to generate the first several (9) rotational eigenstates of the molecule, which is modeled as a rigid, quantum rotor with an anisotropic polarizability and quadrupole moment. The rotor interacts with Na cations and O anions; interaction parameters are chosen semiempirically and the truncation of electrostatic fields is handled with a switching function. A Monte Carlo proceedure is used to sample a set of states based on the canonical distribution. Potential energy surfaces, favorable adsorbtion sites, and distributions of barriers to rotation are analyzed. Separation factors for ortho-parahydrogen …

Method Of Storing Active Zero Valent Zinc Metal, Reuben D. Rieke

Department of Chemistry: Faculty Publications

A novel Zerovalent Zinc species and an organozinc reagent are disclosed. The Zerovalent Zinc species is directly pro duced by reaction of a reducing agent on a Zinc Salt, preferably Zn(CN). The organozinc regent results from the reaction of the Zerovalent Zinc species and an organic compound having one or more stable anionic leaving groups. These organozinc reagents include a wide spectrum of functional groups in the organic radical, and are useful in a variety of reactions Schemes.

Enhanced Biotransformation Of Carbon Tetrachloride By Acetobacterium Woodii Upon Addition Of Hydroxocobalamin And Fructose, Syed A. Hashsham, David L. Freedman

Publications

The objective of this study was to evaluate the effect of hydroxocobalamin (OH-Cbl) on transformation of high concentrations of carbon tetrachloride (CT) by Acetobacterium woodii (ATCC 29683). Complete transfor-mation of 470 􀀀M (72 mg/liter [aqueous]) CT was achieved by A. woodii within 2.5 days, when 10 􀀀M OH-Cbl was added along with 25.2 mM fructose. This was approximately 30 times faster than A. woodii cultures (live or autoclaved) and medium that did not receive OH-Cbl and 5 times faster than those controls that did receive OH-Cbl, but either live A. woodii or fructose was missing. CT transformation in treatments with …

Fall 1999, Nsu Oceanographic Center

Currents

No abstract provided.

1999 Scholars And Artists Bibliography, Michael Schwartz Library, Cleveland State University, Friends Of The Michael Schwartz Library

Scholars and Artists Bibliographies

This bibliography was created for the annual Friends of the Michael Schwartz Library Scholars and Artists Reception, recognizing scholarly and creative achievements of Cleveland State University faculty, staff and emeriti