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Articles 13591 - 13620 of 14851
Full-Text Articles in Entire DC Network
The Psychological Relevance Of Phonological Generalizations In Spanish: An Experiment, David Eddington
The Psychological Relevance Of Phonological Generalizations In Spanish: An Experiment, David Eddington
Faculty Publications
A psycholinguistic experiment aids in determining if the phonological generalizations which appear in the literature on Spanish phonology are psychologically significant for Spanish speakers. The experiment focuses on whether common phonological alternations play a role in native speakers' perceptions of whether two words share a morpheme. The results indicate that they are a significant factor in speakers' perceptions of morphemic relatedness. Therefore, these findings provide some evidence that these phonological generalizations are psychologically valid, and not merely descriptive in nature.
Default Risk And The Effective Duration Of Bonds, David F. Babbel, Craig B. Merrill, William Panning
Default Risk And The Effective Duration Of Bonds, David F. Babbel, Craig B. Merrill, William Panning
Faculty Publications
Basis risk is the risk attributable to uncertain movements in the spread between yields associated with a particular financial instrument or class of instruments, and a reference interest rate over time. There are seven types of basis risk: Yields on
- Long-term versus short-term financial instruments.
- Domestic currency versus foreign currencies.
- Liquid versus illiquid investments.
- Bonds with higher or lower sensitivity to changes in interest rate volatility.
- Taxable versus tax-free instruments.
- Spot versus futures contracts.
- Default-free versus non-default-free securities.
Basis risk makes it difficult for the fixed-income portfolio manager to measure the portfolio's exposure to interest rate risk, heightens the anxiety …
Health Insurance Availability And The Retirement Decision, Jonathan Gruber, Brigitte C. Madrian
Health Insurance Availability And The Retirement Decision, Jonathan Gruber, Brigitte C. Madrian
Faculty Publications
Because individuals aged 55-64 face large and uncertain medical expenditures without the guarantee of public insurance coverage provided by Medicare, the availability of post-retirement health insurance could be an important detenninant in the retirement decisions of this group. We investigate the effect of health insurance on retirement by focusing on state and federal "continuation of coverage" mandates which grant the retiree the right to continue purchasing health insurance through a previous employer for a specified number of months after leaving the firm. We exploit variation in the timing and generosity of these laws to identify the effect of the availability …
Decreases In The Swelling And Porosity Of Bituminous Coals During Devolatilization At High Heating Rates, Thomas K. Gale, Thomas H. Fletcher, Calvin H. Bartholomew
Decreases In The Swelling And Porosity Of Bituminous Coals During Devolatilization At High Heating Rates, Thomas K. Gale, Thomas H. Fletcher, Calvin H. Bartholomew
Faculty Publications
Concern about comparability and validity of different methods for producing coal chars for reactivity experiments has led to research on the effect of devolatilization conditions on the char physical and chemical structure. Particle diameter and porosity changes during devolatilization significantly affect char oxidation rates. In particular, physical properties of chars prepared in drop tube reactors differ greatly from chars prepared in flat flame burner experiments. Recent data indicate that the presence of oxygen in the gas atmosphere has no effect on swelling until char oxidation has begun. The present research concentrates on the effects of heating rate, particle temperature and …
Effects Of Pyrolysis Conditions On Internal Surface Areas And Densities Of Coal Chars Prepared At High Heating Rates In Reactive And Non-Reactive Atmospheres, Thomas K. Gale, Thomas H. Fletcher, Calvin H. Bartholomew
Effects Of Pyrolysis Conditions On Internal Surface Areas And Densities Of Coal Chars Prepared At High Heating Rates In Reactive And Non-Reactive Atmospheres, Thomas K. Gale, Thomas H. Fletcher, Calvin H. Bartholomew
Faculty Publications
Concern about comparability and validity of different methods for producing coal chars for reactivity experiments has led to research on the effect of devolatilization conditions on the char physical and chemical structure. Particle diameter and porosity changes during devolatilization significantly affect char oxidation rates. In particular, physical properties of chars prepared in drop tube reactors differ greatly from chars prepared in fiat flame burner experiments. Recent data indicate that the presence of oxygen in the gas atmosphere has no effect on swelling until char oxidation has begun. The present research concentrates on the effects of heating rate, particle temperature and …
Thermophoretic Sampling Of Coal-Derived Soot Particles During Devolatilization, Jinliang Ma, Thomas H. Fletcher, Brent W. Webb
Thermophoretic Sampling Of Coal-Derived Soot Particles During Devolatilization, Jinliang Ma, Thomas H. Fletcher, Brent W. Webb
Faculty Publications
Thermophoretic sampling of soot particles formed during high-temperature coal devolatilization is performed in order to examine soot particle sizes and shapes. Coal particles are injected along the centerline of a laminar flow flat flame burner, where a fuel-rich methane-air flame is used as a heat source. Volatiles released from the coal particles form a cloud of soot particles at high temperatures in the absence of oxygen. A carbon-coated microscope grid is briefly inserted into the soot cloud, where the temperature gradient between the soot particles and the cold grid surface causes the migration of soot particles and results in deposition. …
The 1995 National Asian American Studies Examination In U.S. High Schools, Andrew Chin
The 1995 National Asian American Studies Examination In U.S. High Schools, Andrew Chin
Faculty Publications
No abstract provided.
Masters And Lords: Mid-Nineteenth Century U.S. Planters And Prussian Junkers, By Shearer Davis Bowman, Lacy K. Ford, Jr.
Masters And Lords: Mid-Nineteenth Century U.S. Planters And Prussian Junkers, By Shearer Davis Bowman, Lacy K. Ford, Jr.
Faculty Publications
A review of Masters and Lords: Mid-Nineteenth Century U.S. Planters and Prussian Junkers, by Shearer Davis Bowman
The Nuts & Bolts Of Cooperative Learning In Engineering, Nikos J. Mourtos
The Nuts & Bolts Of Cooperative Learning In Engineering, Nikos J. Mourtos
Faculty Publications
A great number of engineering students work alone. But in industry, teamwork is required most of the time. Incorporating Cooperative Learning (CL) into an engineering program gives students an opportunity to practice problem solving and communication skills in a "simulated" professional environment. The paper briefly discusses the motivation behind using CL in engineering courses. Then, the essential elements to make CL successful in the classroom are examined and examples of how these elements have been incorporated into engineering courses taught by the author are given. Problems that have been encountered along with possible fixes are also mentioned.
Fibrinolytic Responses To Moderate Intensity Exercise: Comparison Of Physically Active And Inactive Men, Linda M. Szymanski, Russell R. Pate
Fibrinolytic Responses To Moderate Intensity Exercise: Comparison Of Physically Active And Inactive Men, Linda M. Szymanski, Russell R. Pate
Faculty Publications
The purposes of this study were to compare fibrinolytic responses to moderate intensity exercise in physically active and inactive men and during morning and evening exercise. Fourteen physically inactive men (mean age, 34.7 ± 4.0 years) and 12 regularly active men (34.8 ± 4.0 years) performed two exercise sessions, morning and evening, at 50% of maximal oxygen consumption. Tissue plasminogen activator (TPA) andplasminogen activator inhibitor-1 (PAI-1) activity were measured before and after exercise. Data were analyzed using a three-way ANOVA with repeated measures. TPA actively increased with exercise in both groups, although the active group demonstrated greater increases than the …
Semiclassical Quantization Of A Nonintegrable System: Pushing The Fourier Method Into The Chaotic Regime, Karl Sohlberg, Randall B. Shirts
Semiclassical Quantization Of A Nonintegrable System: Pushing The Fourier Method Into The Chaotic Regime, Karl Sohlberg, Randall B. Shirts
Faculty Publications
Semiclassical Einstein–Brillouin–Keller (EBK) quantization of the nonintegrable Hénon–Heiles Hamiltonian succeeds using the Fourier transform method of Martens and Ezra. Two innovations are required for this success: (1) the use of tunneling corrected quantizing actions obtained from an approximate, one-dimensional Hamiltonian and (2) exploitation of intermediate-time approximate quasiperiodicity or "vague tori'' wherein the Fourier transform of chaotic motion over 10–100 vibrational periods allows the determination of frequencies and amplitudes which approximate motion during the time interval. Approximate tori, actions, and EBK energy levels are then straightforward. We use an interpolation method to smooth over small resonance zones that are not expected …
Descriptive Epidemiology Of Physical Activity In Adolescents, Russell R. Pate, Barbara J. Long, Gregory W. Heath
Descriptive Epidemiology Of Physical Activity In Adolescents, Russell R. Pate, Barbara J. Long, Gregory W. Heath
Faculty Publications
This paper reviews the descriptive epidemiology of physical activity in adolescents. Large population-based studies were reviewed, along with smaller studies using objective monitoring of physical activity. Estimates showed that adolescents engage in physical activity of any intensity for a mean of one hour per day. Approximately two thirds of males and one quarter of females participate in moderate to vigorous activity for 20 min 3 or more days per week. Activity levels decline with increasing age across adolescence, and this decrease is more marked in females than in males. Comparison of these data to physical activity guidelines for adolescents suggests …
Hernando Desoto And The Indians Of Florida, By Jerald T. Milanich And Charles Hudson, Michael C. Scardaville
Hernando Desoto And The Indians Of Florida, By Jerald T. Milanich And Charles Hudson, Michael C. Scardaville
Faculty Publications
A review of Hernando DeSoto and the Indians of Florida, by Jerald T. Milanich and Charles Hudson
Ultrasonic Enhancement Of Antibiotic Action On Gram-Negative Bacteria, William G. Pitt, Michael O. Mcbride, Jared K. Lunceford, Randall J. Roper, Richard D. Sagers
Ultrasonic Enhancement Of Antibiotic Action On Gram-Negative Bacteria, William G. Pitt, Michael O. Mcbride, Jared K. Lunceford, Randall J. Roper, Richard D. Sagers
Faculty Publications
The effect of gentamicin upon planktonic cultures of Pseudomonas aeruginosa, Escherichia coli, Staphylococcus epidermidis, and Staphylococcus aureus was measured with and without application of 67-kHz ultrasonic stimulation. The ultrasound was applied at levels that had no inhibitory or bactericidal activity against the bacteria. Measurements of the MIC and bactericidal activity of gentamicin against planktonic cultures of P. aeruginosa and E. coli demonstrated that simultaneous application of 67-kHz ultrasound enhanced the effectiveness of the antibiotic. A synergistic effect was observed and bacterial viability was reduced several orders of magnitude when gentamicin concentrations and ultrasonic levels which by themselves did not reduce …
A Vlsi Implementation Of A Parallel, Self-Organizing Learning Model, Tony R. Martinez, George L. Rudolph, Linton G. Salmon, Matthew G. Stout
A Vlsi Implementation Of A Parallel, Self-Organizing Learning Model, Tony R. Martinez, George L. Rudolph, Linton G. Salmon, Matthew G. Stout
Faculty Publications
This paper presents a VLSI implementation of the Priority Adaptive Self-organizing Concurrent System (PASOCS) learning model that is built using a multi-chip module (MCM) substrate. Many current hardware implementations of neural network learning models are direct implementations of classical neural network structures - a large number of sample computing nodes connected by a dense number of weighted links. PASOCS is one of a class of ASOCS (Adaptive Self-Organizing Concurrent System) connectionist models whose overall goal is the same as classical neural networks models, but whose functional mechanisms differ significantly. This model has potential application in areas such as pattern recognition, …
Characterization Of The Near-Interface Region Of Chemical Vapor Deposited Diamond Films On Silicon By Backscatter Kikuchi Diffraction, Brent L. Adams, K. Kunze, S. Geier, R. Hessmer, M. Schreck, B. Rauschembach, B. Stritzker
Characterization Of The Near-Interface Region Of Chemical Vapor Deposited Diamond Films On Silicon By Backscatter Kikuchi Diffraction, Brent L. Adams, K. Kunze, S. Geier, R. Hessmer, M. Schreck, B. Rauschembach, B. Stritzker
Faculty Publications
The lattice orientations near the interface of chemical vapor deposited diamond films on Si(001) have been studied by orientation imaging microscopy. This technique is based on the automated analysis of electron backscatter Kikuchi diffraction patterns. The electron beam has been scanned in discrete steps over the reverse side of the diamond film after having removed the substrate. The obtained data have allowed us to determine the texture and to visualize quantitatively the orientational arrangement of and among individual diamond crystallites in the near-interface region. A comparison with the orientation of the substrate has proved the existence of epitaxially nucleated grains. …
Low Cost Schottky Barrier Solar Cells Fabricated On Cdse And Sb2S3 Films Chemically Deposited With Silicotungstic Acid, O. Savadogo, K. C. Mandal
Low Cost Schottky Barrier Solar Cells Fabricated On Cdse And Sb2S3 Films Chemically Deposited With Silicotungstic Acid, O. Savadogo, K. C. Mandal
Faculty Publications
No abstract provided.
Automating Workflows For Service Provisioning: Integrating Ai And Database Technologies, Munindar P. Singh, Michael N. Huhns
Automating Workflows For Service Provisioning: Integrating Ai And Database Technologies, Munindar P. Singh, Michael N. Huhns
Faculty Publications
Workflows are the structured activities that take place in information systems in typical business environments. These activities frequently involve several database systems, user interfaces, and application programs. Traditional database systems do not support workflows to any reasonable extent: usually human beings must intervene to ensure their proper execution. We have developed an architecture based on AI technology that automatically manages workflows. This architecture, which executes on top of a distributed computing environment, has been applied to automating service provisioning workflows; an implementation that operates on one such workflow has been developed. This work advances the Carnot Project’s goal of developing …
Spiders: A New User Interface For Rotation And Visualization Of N-Dimensional Point Sets, William A. Barrett, Kirk L. Duffin
Spiders: A New User Interface For Rotation And Visualization Of N-Dimensional Point Sets, William A. Barrett, Kirk L. Duffin
Faculty Publications
We present a new method for creating n-dimensional rotation matrices from manipulating the projections of n-dimensional data coordinate axes onto a viewing plane. A user interface for n-dimensional rotation is implemented. The interface is shown to have no rotational hysteresis.
Contextual Interference Effects In The Acquisition And Retention Of Motor Tasks By Individuals With Mild Mental Handicaps, William J. Vincent, Mary A. Painter, Kathleen B. Inman
Contextual Interference Effects In The Acquisition And Retention Of Motor Tasks By Individuals With Mild Mental Handicaps, William J. Vincent, Mary A. Painter, Kathleen B. Inman
Faculty Publications
The effects of contextual interference on motor skill acquisition and retention were examined in 24 subjects (mean age 13.9 years) with mild mental retardation and 24 chronologically age-matched subjects (mean age 13.11 years) with no disabilities. Subjects from each group were assigned randomly to either a blocked or a random practice schedule. All subjects performed 15 practice trials for each of three different beanbag throwing tasks, 45 trials total. Following a 10-min filled retention interval, 2 trials of each throw (6 total) were performed in a random order by all subjects. Accuracy scores were measured as absolute error from the …
The Structure And Dynamics Of The Cs2 Molecular Ion, Karl Sohlberg, Chan Yibai
The Structure And Dynamics Of The Cs2 Molecular Ion, Karl Sohlberg, Chan Yibai
Faculty Publications
Several common elementary methods of computing molecular properties, prerequisite to molecular dynamics studies, are tested for their validity for CS+2. Judged sufficiently accurate, these methods are then used to aid in investigating the collisionally activated dissociation of CS+2 upon impact with xenon. Rice–Ramsperger–Kassel–Marcus (RRKM) unimolecular decay rate calculations are presented and compared to experimental studies employing collisional activation. RRKM theory is shown to reproduce the experimental results for collision energies near threshold. When corrected for vibrational anharmonicity, the RRKM calculation shows agreement with the experimental results over a slightly wider range of energies. A discussion is given on the applicability …
Thomas Hobbes's "A Discourse Of Laws", Noel B. Reynolds
Thomas Hobbes's "A Discourse Of Laws", Noel B. Reynolds
Faculty Publications
The recent discovery that an anonymously published 1620 essay was an early writing of Thomas Hobbes invites investigation of his early thinking. Hobbes relied on mostly classical sources to advance a basically conventionalist theory of law and to anticipate twentieth century analyses of the principles of rule of law such as that made famous by F. A. Hayek.
The Effects Of Gender On Career Decision Problems In Young Adults, Jeffry H. Larson, Mark Butler, Stephan Wilson, Nilufer Medora, Scot Allgood
The Effects Of Gender On Career Decision Problems In Young Adults, Jeffry H. Larson, Mark Butler, Stephan Wilson, Nilufer Medora, Scot Allgood
Faculty Publications
The authors investigated gender differences in psychological problems in the career decision-making (CDM) process of young adults. Specifically, problems with decision anxiety, life-goal awareness, luck-fate orientation, authority orientation, and secondary gain motivation were investigated. Methodology involved administering the Career Decision Diagnostics Assessment (CDDA) instrument to 1,006 college students from four universities. Results indicated no gender differences in global levels of problems in CDM. Women reported more problems with life-goal awareness and authority orientation than did men. Men reported more problems with secondary gain motivations than did women. The results are discussed in terms of implications for gender-differentiated career counseling.
Performance Analysis Of Antennas For Hand-Held Transceivers Using Fdtd, Michael A. Jensen, Yahya Rahmat-Samii
Performance Analysis Of Antennas For Hand-Held Transceivers Using Fdtd, Michael A. Jensen, Yahya Rahmat-Samii
Faculty Publications
The design of antennas for hand-held communications devices depends on the implementation of simulation tools that can accurately model general topologies. The paper presents the analysis of small antennas mounted on hand-held transceivers using the finite-difference time-domain (FDTD) method. The key features of the FDTD implementation are discussed, with particular emphasis placed upon modeling of the source region. The technique is used to predict the gain patterns and broadband input impedance behavior of monopole, planar inverted F, and loop antenna elements mounted on the handset. Effects of the conducting handset chassis, the plastic casing around the device, and lumped elements …
Characterization Of The Near-Interface Region Of Chemical Vapor Deposited Diamond Films On Silicon By Backscatter Kikuchi Diffraction, Brent L. Adams, K. Kunze, S. Geier, R. Hessmer, B. Rauschembach, M. Schreck, B. Stritzker
Characterization Of The Near-Interface Region Of Chemical Vapor Deposited Diamond Films On Silicon By Backscatter Kikuchi Diffraction, Brent L. Adams, K. Kunze, S. Geier, R. Hessmer, B. Rauschembach, M. Schreck, B. Stritzker
Faculty Publications
B.L.A. and K.K. gratefully acknowledge support under a Materials Research Group Award by the National Science Foundation No. DMR-9001278. Also the software support by Th. Bollmeier is greatly appreciated. The lattice orientations near the interface of chemical vapor deposited diamond films on Si(001) have been studied by orientation imaging microscopy. This technique is based on the automated analysis of electron backscatter Kikuchi diffraction patterns. The electron beamhas been scanned in discrete steps over the reverse side of the diamond film after having removed the substrate. The obtained data have allowed us to determine the texture and to visualize quantitatively the …
Providing An Escape For Inner-City Children: Creating A Federal Remedy For Educational Ills Of Poor Urban Schools, Amy J. Schmitz
Providing An Escape For Inner-City Children: Creating A Federal Remedy For Educational Ills Of Poor Urban Schools, Amy J. Schmitz
Faculty Publications
Children in impoverished, urban areas attend dangerous and decrepit schools, where they receive low quality education which fails to prepare them for meaningful participation in the community. Many states, however, provide no legislative or judicial remedy for these children, who desperately need vocational and educational skills to enable them to escape from the deprivation of their urban landscape. Meanwhile, federal officials speak
The Answering Machine Generation - Who Are They And What Problem Do They Pose For Survey Research, Robert W. Oldendick, Michael W. Link
The Answering Machine Generation - Who Are They And What Problem Do They Pose For Survey Research, Robert W. Oldendick, Michael W. Link
Faculty Publications
Increased incidence of telephone answering machines and the use of such devices to screen calls pose a potential threat to the representativeness of samples in telephone surveys. Using data from nine statewide surveys, this analysis examines the extent to which answering machines are used to screen calls and the demographic characteristics associated with answering machine use and call screening. Results show that at most two to three percent of households use answering machines to screen calls, and that such screening is more likely to take place in households with higher family incomes, outside rural areas, and which include individuals who …
Aging And Exercise: A Health Perspective, Joanna L. Bokovoy, Steven N. Blair
Aging And Exercise: A Health Perspective, Joanna L. Bokovoy, Steven N. Blair
Faculty Publications
Habitual exercise provides protection against fatal coronary heart disease, extends longevity, and enhances quality of life. National surveys show less physical activity in older men and women compared with middle-aged and younger persons; older women are particularly sedentary. Although there are still few longitudinal studies on exercise and physical activity in older individuals, the data support a positive relationship between physical activity and health function in older individuals. The data further show that with regular physical activity, health and fitness are maintained or even increased over time in older individuals. Studies on physical activity requirements for beneficial health effects in …
Raman Spectroscopic Study Of The Formation Of T-Mosi2 From Mo/Si Multilayers, Ming Cai, David D. Allred, A. Reyes-Mena
Raman Spectroscopic Study Of The Formation Of T-Mosi2 From Mo/Si Multilayers, Ming Cai, David D. Allred, A. Reyes-Mena
Faculty Publications
We have used Raman spectroscopy, large- and small-angle x-ray diffraction spectroscopy of sputter-deposited, vacuum-annealed, soft x-ray Mo/Si thin-film multilayers to study the physics of silicide formation. Two sets of multilayer samples with d-spacing 8.4 and 2.0 nm have been studied. Annealing at temperatures above 800 °C causes a gradual formation of amorphous MoSi2 interfaces between the Si and Mo layers. The transition from amorphous to crystalline MoSi2 is abrupt. The experimental results indicate that nucleation is the dominant process for the early stage and crystallization is the dominant process after nucleation is well advanced. In the thicker multilayer, a portion …
Emitted Current Instability From Silicon Field Emission Emitters Due To Sputtering By Residual Gas Ions, W.I. Karain, Larry V. Knight, David D. Allred, A. Reyes-Mena
Emitted Current Instability From Silicon Field Emission Emitters Due To Sputtering By Residual Gas Ions, W.I. Karain, Larry V. Knight, David D. Allred, A. Reyes-Mena
Faculty Publications
We have fabricated arrays of silicon field emitters using semiconductor lithography techniques. The density of the tips was 10^5/cm^2. The maximum current that can be extracted from each emitter is limited by resistive heating. We have investigated how the electron current emitted changes under constant applied voltage. We found that the current is very sensitive to the vacuum conditions. We attribute this to sputtering of the emitters due to ionized residual gas molecules. The poorer the vacuum, the higher the instability in the current. We studied this phenomenon at 10^6 and 10-x Torr. The model of two concentric spherical shells …