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Adaptive Detection Of Pn-Spread Psk Waveforms In Hf Atmospheric Noise, M. A. Wadsworth

Theses

The purpose of this work is to investigate optimal methods for the detection of short duration (burst) PN-spread PSK waveforms in HF atmospheric noise. As has been shown, the optimal detector for any waveform in Gaussian background noise is a matched filter. However, HF atmospheric noise is non-Gaussian, necessitating alternate detector designs. A theoretical approach to an alternate detector design is taken, based on radar clutter modeling techniques and concepts from detection theory. The industry standard model for HF atmospheric noise is contained in COR Report 322-3 (1986). The CCLR 322 noise model is a graphical, empirical model based on …

Hubble Space Telescope Images And Spectra Of The Remnant Of Sn 1885 In M31, Robert A. Fesen, Christopher L. Gerardy, Kevin M. Mclin, Andrew J. S. Hamilton

Dartmouth Scholarship

Near-UV Hubble Space Telescope images of the remnant of SN 1885 (S And) in M31 show a 070±005 diameter absorption disk silhouetted against M31's central bulge, at SN 1885's historically reported position. The disk's size corresponds to a linear diameter of 2.5±0.4 pc at a distance of 725±70 kpc, implying an average expansion velocity of 11,000±2000 km s-1 over 110 yr. Low-dispersion Faint Object Spectrograph spectra over 3200-4800 Å reveal that the absorption arises principally from Ca II H and K (equivalent width 215 Å), with weaker absorption features of Ca I 4227 Å and Fe I 3720 Å. The …

Peculiar Velocity Dipoles Of Field Galaxies, Riccardo Giovanelli, Martha P. Haynes, Wolfram Freudling, Luiz N. Da Costa, John J. Salzer, Gary Wegner

Dartmouth Scholarship

The Tully-Fisher (TF) relation is applied to obtain peculiar velocities of field spiral galaxies and to calculate dipoles of the peculiar velocity field to cz8000 km s^-1. The field galaxy sample is spatially coextensive with and completely independent of a cluster sample, for which dipole characteristics are given in a separate paper. Dipoles of the peculiar velocity field are obtained separately by applying (1) an inverse version of the TF relation and selecting galaxies by redshift windowing and (2) a direct TF relation, with velocities corrected for the inhomogeneous Malmquist bias and windowing galaxies by TF distance. …

A Note On The Green Dyadic Calculation Of The Decay Rates For Admolecules At Multiple Planar Interfaces, P.T. Leung, R. L. Hartman, Scott M. Cohen

Physics Faculty Publications and Presentations

The Green dyadic formulation for calculating classical decay rates of admolecules at multiple planar interfaces first published by Chance, Prock and Silbey is reexamined. It is pointed out that, for the case of fluorescing molecules sandwiched between a system of super- and substrate interfaces, the original formalism requires significant modifications in order to lead to results consistent with those obtained from the Sommerfeld radiation theory.

Complexity Reduction In State-Based Modeling, Martin Zwick

Complex Systems Faculty Publications and Presentations

For a system described by a relation among qualitative variables (or quantitative variables "binned" into symbolic states), expressed either set-theoretically or as a multivariate joint probability distribution, complexity reduction (compression of representation) is normally achieved by modeling the system with projections of the overall relation. To illustrate, if ABCD is a four variable relation, then models ABC:BCD or AB:BC:CD:DA, specified by two triadic or four dyadic relations, respectively, represent simplifications of the ABCD relation. Simplifications which are lossless are always preferred over the original full relation, while simplifications which lose constraint are still preferred if the reduction of complexity more …

Morphogenesis Of Douglas Fir Buds Is Altered At Elevated Temperature But Not At Elevated Co2, Martha E. Apple, Melissa S. Lucash, David M. Olszyk, David T. Tingey

Environmental Science and Management Faculty Publications and Presentations

Global climatic change as expressed by increased CO₂ and temperature has the potential for dramatic effects on trees. To determine what its effects may be on Pacific Northwest forests, Douglas-fir (Pseudotsuga menziesii ) seedlings were grown in sun-lit controlled environment chambers at ambient or elevated (+4°C above ambient) temperature, and at ambient or elevated (+200 ppm above ambient) CO₂. In 1995–1996 and 1996–1997, elevated CO₂ had no effect on vegetative bud morphology, while the following unusual morphological characteristics were found with greater frequency at elevated temperature than at ambient: rosetted buds with reflexed and loosened outer …

Saturation Control For Reduction Of Rotor Blade Lag Vibration, Sayam Saguanrum

Mechanical & Aerospace Engineering Theses & Dissertations

Within the context of this research, the performance of saturation control for reduction in the vibratory lag motion of helicopter rotor blades is investigated. The single-degree-of-freedom plant, which consists of a spring and damper attached to the rotor blade, is perturbed by an aerodynamic force, and produces the unwanted vibration. To restrict this vibration, the second-order controller is provided to couple with the blade system. It works adaptively, when the system is excited and the controller frequency is set at half of the blade lag frequency in accordance with the relationship of both natural frequencies. The nonlinear terms from the …

Variability Analysis Of Discrete Cosine Transform Coefficient (Dctc) Features For Speech Processing, Bingjun Dai

Electrical & Computer Engineering Theses & Dissertations

In this research, the variability of Discrete Cosine Transform Coefficient (DCTC) features was investigated. Additionally, a new pitch-synchronous processing method was explored to increase the stability of features and to reduce window effects when compared to the regular method. The noise sources that lead to feature variability were analyzed, and different smoothing methods were tested. It was found that longer frames, frequency warping, time smoothing of the log spectrum, and DCS level time smoothing, all help reduce DCTC variability and increase classification performance. The pitch­ synchronous method was implemented with Matlab. Important processing methods, including pitch period estimation, time­ domain …

Computer Simulations Of Electromigration Based On A Molecular Dynamics Approach, John Stephen Peake

Electrical & Computer Engineering Theses & Dissertations

Most research on electromigration has centered around macroscopic simulations of electromigration where a value for the diffusion coefficient was assumed to be spatially uniform throughout the material. The research in this thesis goes a step further and, through microscopic molecular dynamics computer simulations, calculates and updates the atomic drift velocity and atomic position as a function of time to analyze how various defects within the conductor affect these quantities. The simulations are carried out with defects in the form of dislocation half-planes placed in different locations within the simulation space. The atomic drift velocity and position changes derived from these …

The Mentoring Experiences Of College And High School Seniors, Clenise Rachelle Platt

Psychology Theses & Dissertations

The purpose of this study was to examine the mentoring experiences of high school seniors and college seniors. One hundred and one Caucasian ( 49 men and 52 women) and 34 African-American (9 men and 24 women) and 14 Other race (8 men and 6 women) college seniors and high school seniors participated in this study. There were 107 high school senior and 50 college senior participants.

The objective of this study was to examine the mentoring experiences of college and high school seniors and their effects on: (a) the educational goals of the participants; (b) the goal facilitating behaviors …

Investigating The Effects Of Subtle Ratee Characteristics In Team Performance Appraisal: The Influence Of Personality And Cohesiveness, Jonathan Quinn Schroeder

Psychology Theses & Dissertations

This study extends the research into systematic bias in performance appraisal to include subtle (i.e., not overtly demographic) ratee characteristics. Specifically examined were the biasing effects of personality and group cohesiveness on performance ratings. It was hypothesized that raters' personality inferences regarding ratees' levels of agreeableness and conscientiousness would correlate with bias in performance ratings. Interpersonal group cohesiveness was also hypothesized to affect rating accuracy. Research participants (n = 90) rated the performance of two videotaped leaderless group discussions. Personality inferences correlated strongly with leniency in performance ratings. In addition, significant differences in accuracy were found between the more and …

Chemical Modification Of Cvd Diamond Electrodes, Robert Matthew Johnson

Chemistry & Biochemistry Theses & Dissertations

The micro-array behavior of boron doped CVD diamond thin film electrodes has been studied in acetonitrile containing two redox couples. The analytical technique employed in these studies was cyclic voltammetry. One system is 0.4 mM ferrocene containing 0.1 M tetrabutylammonium hexafluorophosphate (TBAH). This reversible redox system is not only well-known, but also involves only one electron transfer with no breakage/formation of chemical bonds, thus making it a simple system for analysis. The second test is 0.8 mM cobaltocenium hexafluorophosphate, with 0.4 mM ferrocene as an internal standard. Unlike ferrocene, which is neutral initially, cobaltocenium is positively charged, and is reduced …

Two Dimensional, Time Dependent Modeling And Simulation Of Semi-Insulating Gaas High-Power Photoconductive Switches, Prakasit Kayasit

Electrical & Computer Engineering Theses & Dissertations

The current-voltage (I-V) characteristics and photoconductive behavior of semi-insulating GaAs (SI GaAs) high-power switches have been investigated by using a two-dimensional, time dependent, drift diffusion transport model. The dc current-voltage behavior as predicted by the results of this model was compared with available experimental data to evaluate the accuracy and validity of the model. The results show very good agreement, Next, research was carried out to investigate the behavior of the switches under high-field operation.

Simulations at high voltages emphasize on the two following processes: (a) The mechanism of impact ionization and the effect of this mechanism on device stability …

Design Optimization Of Magnetic Bearings And Magnetic Suspension Systems, V. Dale Bloodgood Jr.

Mechanical & Aerospace Engineering Theses & Dissertations

Magnetic suspension systems were first demonstrated as practical by Holmes and Beams in the 1930's. Since then, numerous academic researchers have worked with various types of these systems. Commercial applications have largely been limited to magnetic bearings for rotating machinery. Other applications that have held considerable promise include wind tunnel model suspensions, space payload pointing and vibration isolation systems, satellite momentum storage and control devices and electromagnetic launch systems. However, none of these have progressed significantly beyond the prototype stage. Maglev trains have not reached serious commercial service but are being aggressively developed in Germany and Japan.

Design methods for …

September 30, 1998 Cal Poly Report, Public Affairs Office

Cal Poly Report

No abstract provided.

09-30-98 (The Liberty Champion, Volume 16, Issue 5)

1998 -- 1999

No abstract provided.

Spartan Daily, September 30, 1998, San Jose State University, School Of Journalism And Mass Communications

Spartan Daily (School of Journalism and Mass Communications)

Volume 111, Issue 22

Hexapod Herald - Vol. 10, No. 8, September 30, 1998

Hexapod Herald and Other Entomology Department Newsletters

Faculty news

Publications

Graduate news

Travel

Museum news

Speakers: E. O. Wilson. October 13, 1998

Conferences

Calendar of events

The Pan American (1998-09-29), Javier J. Mancha

UTPA Archives - The Pan American Newspaper

47th Year, No. 8

On Campus, September 28, 1998, Coastal Carolina University

On Campus Newsletter

A Newsletter for Faculty and Staff of Coastal Carolina University. Volume 8, Number 15

Commonwealth Times 1998-09-28

Commonwealth Times, 1969-

No abstract provided.

Grand Valley Forum, Volume 023, Number 09, September 28, 1998, Grand Valley State University

1998-1999, Volume 23

Grand Valley Forum is Grand Valley State's faculty and staff newsletter, published from 1976 to the present.

Faculty Newsnotes 1998 No. 311, Office Of The Provost

Faculty Newsnotes (1972-2010)

No abstract provided.

Monitor Newsletter September 28, 1998, Bowling Green State University

Monitor

Official Publication of Bowling Green State University for Faculty and Staff

Undergraduate Curriculum And Academic Policy Minutes, September 28, 1998 And 1998-1999 Committee Member List

Undergraduate Curriculum and Academic Policy Committee Minutes

Committee member list and minutes from the Wright State University Faculty Senate Undergraduate Curriculum and Academic Policy Committee meeting held on September 28, 1998.

September 28, 1998 Reporter, University Of Alabama At Birmingham

eReporter (campus newsletter)

No abstract provided.

University Of Northern Iowa Faculty Senate Meeting Agenda, September 28, 1998, University Of Northern Iowa. Faculty Senate.

Documents - Faculty Senate

Meeting agenda from the Faculty Senate of the University of Northern Iowa.

University Of Northern Iowa Faculty Senate Meeting Minutes, September 28, 1998, University Of Northern Iowa. Faculty Senate.

Documents - Faculty Senate

Meeting minutes from the Faculty Senate of the University of Northern Iowa.

75th Annual Harding University Lectureship Program (1998), Harding University

Lectureship Programs

This document contains the printed lectureship schedule.

1998 Otterbein Vs John Carroll University Football Program, Otterbein University

Football Programs

No abstract provided.