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Physics

1993

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Articles 1 - 30 of 334

Full-Text Articles in Physical Sciences and Mathematics

A Theoretical Investigation Of The Geometries, Vibrational Frequencies, And Binding Energies Of Several Mixed Alkali Halide Dimers, Robert J. Cave, Ian Ono '94 Dec 1993

A Theoretical Investigation Of The Geometries, Vibrational Frequencies, And Binding Energies Of Several Mixed Alkali Halide Dimers, Robert J. Cave, Ian Ono '94

All HMC Faculty Publications and Research

Results are presented from ab initio calculations on several mixed alkali halide dimers made up of Li, Na, F, and Cl. All of the dimers are investigated at the restricted Hartree–Fock level to provide ab initio estimates of geometries, vibrational frequencies, and binding energies. The dimer LiNaF2 is then treated using a variety of basis sets at the Hartree–Fock level, as well as at correlated levels (second‐order Møller–Plesset and coupled‐cluster singles and doubles) to examine the sensitivity of the calculations to use of higher levels of theory. The results are then compared to the experimental data available for the LiNaF2 …

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Evidence For Day-To-Night Ion Transport At Low Solar Activity In The Venus Pre-Dawn Ionosphere, J. F. Brannon, Jane L. Fox, H. S. Porter Dec 1993

Evidence For Day-To-Night Ion Transport At Low Solar Activity In The Venus Pre-Dawn Ionosphere, J. F. Brannon, Jane L. Fox, H. S. Porter

Physics Faculty Publications

Periapsis of the Pioneer Venus spacecraft dropped below 180 km on August 28, 1992 near midnight, and 42 orbits of low altitude data at moderately low solar activity in the pre-dawn sector were obtained before contact was lost to the spacecraft in October, 1992. Through a combination of analysis of data from the PV orbiter ion mass spectrometer (OIMS) and modeling, we consider here what can be learned about the relative importance of plasma transport from the dayside and electron precipitation in maintaining the nightside ionosphere during the re-entry period. In particular, we examine here the atomic ion density profiles. …

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Final State Distributions For Electron Capture From Orientated Rydberg Atoms, Jee-Ching Wang, Ronald E. Olson Dec 1993

Final State Distributions For Electron Capture From Orientated Rydberg Atoms, Jee-Ching Wang, Ronald E. Olson

Chemical and Biochemical Engineering Faculty Research & Creative Works

Final state nim distributions are studied for electron capture from orientated circular Rydberg atoms. Strong orientation effects are found for all quantum numbers at collision speeds comparable to the electron orbital speed. Predominant population of large m states is observed when the plane of the circular orbit is nearly perpendicular to the incident direction of the projectile. The Ini distributions show structures due to quasi-Thomas scattering even at low relative collision velocities. © 1993 IOP Publishing Ltd.

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Neutron Reflection Interferometry: Physical Principles Of Surface Analysis With Phase Information, Vladimir Gudkov, G. I. Opat, A. G. Klein Dec 1993

Neutron Reflection Interferometry: Physical Principles Of Surface Analysis With Phase Information, Vladimir Gudkov, G. I. Opat, A. G. Klein

Faculty Publications

It is shown that the analysis of surface layers by neutron reflection interferometry is considerably enhanced by performing the reflectometry with phase information. We discuss two methods of providing such information. One method involves physically adding an extra reference layer, whose amplitude and phase are known theoretically. The other uses the Lloyd's mirror configuration, in which a directly propagating ray that interferes with the reflected ray supplies the phase information. The methods have much in common with holography.

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Giant Energy Product In Nanostructured Two-Phase Magnets , Ralph Skomski, J.M.D. Coey Dec 1993

Giant Energy Product In Nanostructured Two-Phase Magnets , Ralph Skomski, J.M.D. Coey

Ralph Skomski Publications

Exchange hardening of nanostructured two-phase systems composed of an aligned hard phase and a soft phase with high magnetization is investigated using an approach which yields analytic nucleation fields from the micromagnetic vector equation, and accounts for interactions between the soft regions. In suitable structures the nucleation field is proportional to the volume-averaged anisotropy constant. For example, a multilayer composed of alternating 2.4 nm hard-magnetic Sm2Fe17N3 layers and 9 nm Fe65Co35 layers can have an energy product as high as 1 MJ/m3 (120 MG Oe), with a rare-earth content of only …

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A Random Wave Method For Detecting Phase Imbalance In A Coherent Radar Receiver, Zhenni Wang, Alexander Kostinski Dec 1993

A Random Wave Method For Detecting Phase Imbalance In A Coherent Radar Receiver, Zhenni Wang, Alexander Kostinski

Department of Physics Publications

The question of monitoring the angle between the in-phase (I) and quadrature (Q) channels of a coherent radar receiver is considered in this paper. Random interference-type scattering (e.g., rain echo) is assumed so that the received signal is a random phasor sum. It is also assumed that I and Q voltages have a (90 + ϕ0) phase difference. The effects of nonzero phase imbalance ϕ0 on the I and Q statistics are examined. Joint I and Q as well as amplitude and phase probability distributions are derived. It is shown that the cross-correlation …

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Rock Magnetic Criteria For The Detection Of Biogenic Magnetite, Bruce M. Moskowitz, Richard B. Frankel, Dennis A. Bazylinski Dec 1993

Rock Magnetic Criteria For The Detection Of Biogenic Magnetite, Bruce M. Moskowitz, Richard B. Frankel, Dennis A. Bazylinski

Physics

We report results on the magnetic properties of magnetites produced by magnetotactic and dissimilatory iron-reducing bacteria. Magnetotactic bacterial (MTB) strains MS1, MV1 and MV2 and dissimilatory iron-reducing bacterium strain GS-15, grown in pure cultures, were used in this study. Our results suggest that a combination of room temperature coercivity analysis and low temperature remanence measurements provides a characteristic magnetic signature for intact chains of single domain (SD) particles of magnetite from MTBs. The most useful magnetic property measurements include: (1) acquisition and demagnetization of isothermal remanent magnetization (IRM) using static, pulse and alternating fields; (2) acquisition of anhysteretic remanent magnetization …

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Two-Temperature Discrete Model For Nonlocal Heat Conduction, Sergey Sobolev Dec 1993

Two-Temperature Discrete Model For Nonlocal Heat Conduction, Sergey Sobolev

Sergey Sobolev

The two-temperature discrete model for heat conduction in heterogeneous media is proposed. It is shown that the discrete model contains as limiting cases both hyperbolic and parabolic heat conduction equations for propagative and diffusive regimes, respectively. To obtain these limiting cases two different laws of continuum limit have been introduced. The evolution of the two-temperature system comprises three stages with distinct time scales : fast relaxation of each subsystem to local equilibrium, energy exchange between the subsystems and classical hydrodynamics.

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Onset Of Convection For Autocatalytic Reaction Fronts In A Vertical Slab, J. Huang, D. A. Vasquez, Boyd F. Edwards, P. Kolodner Dec 1993

Onset Of Convection For Autocatalytic Reaction Fronts In A Vertical Slab, J. Huang, D. A. Vasquez, Boyd F. Edwards, P. Kolodner

All Physics Faculty Publications

A fully three-dimensional linear stability analysis shows that ascending autocatalytic reaction fronts in vertical slabs are unstable to convection for large-wavelength perturbations at all finite values of the dimensionless driving parameter S=δga3/νDC. This parameter involves a fractional density difference δ between the unreacted and reacted fluids, the acceleration of gravity g, the slab width a, the kinematic viscosity ν, and the catalyst molecular diffusivity DC. Buoyancy dominates over the competing curvature dependence of the front velocity in a band 0c of unstable dimensionless wave numbers, with qc→S/24 as S→0 and qc …

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Recombination Of 2-Dimensional Electrons With Free Light And Heavy Holes In Alxga1-Xas-Gaas Single Heterojunctions In A Magnetic-Field, D. C. Reynolds, David C. Look, B. Jogai, C. E. Stutz Dec 1993

Recombination Of 2-Dimensional Electrons With Free Light And Heavy Holes In Alxga1-Xas-Gaas Single Heterojunctions In A Magnetic-Field, D. C. Reynolds, David C. Look, B. Jogai, C. E. Stutz

Physics Faculty Publications

Landau-level oscillations are observed in the photoluminescence from an AlxGa1-xAs-GaAs single heterojunction in an applied magnetic field. Extrapolating the oscillations back to zero field gives the energy of the transition from the two-dimensional (2D) electrons to the free heavy holes (hh1 and hh2) and free light holes (lh) weakly confined in the GaAs active layer. The measured energy separation between hh1 and lh is 1.8 meV, which agrees very well with the calculated value of 2.2 meV. The measured energy separation between hh1 and hh2 is 3.8 meV, in good agreement with the calculated value of …

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System Design Analysis Of A Lightweight Laser Satellite Terminal, Brian C. Page Dec 1993

System Design Analysis Of A Lightweight Laser Satellite Terminal, Brian C. Page

Theses and Dissertations

This study investigated the technological feasibility of a man- portable satellite laser communications system. Areas of interest were an end- to-end system analysis on the communications link evaluation of atmospheric effects and evaluation of semi-conductor lasers as the laser source. A literature search revealed that satellite laser communication research is primarily directed at inter-satellite links. There have been some proposed systems for space-to-ground laser communications systems, but they all utilize large fixed ground stations. The focus of this research effort is directed at a small man-portable ground station capitalizing on recent advances in semiconductor laser devices. Baseline satellite communication systems …

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Neutron-Diffraction And Mössbauer-Effect Studies Of Pr₂(Fe₁₋ₓmnₓ)₁₄B, Oran Allan Pringle, Jie Fu, Gary J. Long, William Joseph James, Decai Xie, William B. Yelon, Fernande Grandjean Dec 1993

Neutron-Diffraction And Mössbauer-Effect Studies Of Pr₂(Fe₁₋ₓmnₓ)₁₄B, Oran Allan Pringle, Jie Fu, Gary J. Long, William Joseph James, Decai Xie, William B. Yelon, Fernande Grandjean

Physics Faculty Research & Creative Works

A neutron-diffraction investigation of a series of Pr2(Fe 1-xMnx)14B samples, with x values of 0.00, 0.11, 0.22, 0.30, and 0.35, reveals a preference for the manganese to occupy the 8j2 transition-metal site,the transition-metal site with the largest Wigner-Seitz cell volume. Similar site occupancies have been reported previously for Er2(Fe1-xMnx) 14B and Y2(Fe1-xMnx) 14B. An analysis of the 295-K Mössbauer spectrum of Pr2(Fe0.89Mn0.11)14B indicates that the internal hyperfine fields on the …

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The Structural Homogeneity Of Boron Carbide Thin Films Fabricated Using Plasma-Enhanced Chemical Vapor Deposition From B5H9+Ch4, Sunwoo Lee, J. Mazurowski, W.L. O'Brien, Q.Y. Dong, J.J. Jia, T.A. Callcott, K.E. Miyano, D.L. Ederer, D.R. Mueller, Peter A. Dowben Dec 1993

The Structural Homogeneity Of Boron Carbide Thin Films Fabricated Using Plasma-Enhanced Chemical Vapor Deposition From B5H9+Ch4, Sunwoo Lee, J. Mazurowski, W.L. O'Brien, Q.Y. Dong, J.J. Jia, T.A. Callcott, K.E. Miyano, D.L. Ederer, D.R. Mueller, Peter A. Dowben

Peter Dowben Publications

Boron carbide thin films of several B/C ratios have been deposited on Si(111) using plasma-enhanced chemical vapor deposition from nido-pentaborane(9) (B5H9) and methane (CH4). X-ray diffraction studies of boron carbide thin films on Si(111) exhibited characteristic microcrystalline diffraction lines. Soft x-ray emission spectroscopy was used to verify that the local electronic structure and composition of each sample corresponded to a homogeneous solid solution boron carbide phase.

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Short Terahertz Pulses From Semiconductor Surfaces: The Importance Of Bulk Difference‐Frequency Mixing, Peter N. Saeta, Benjamin I. Greene, Shun Lien Chuang Dec 1993

Short Terahertz Pulses From Semiconductor Surfaces: The Importance Of Bulk Difference‐Frequency Mixing, Peter N. Saeta, Benjamin I. Greene, Shun Lien Chuang

All HMC Faculty Publications and Research

The crystallographic orientation dependence of the far‐infrared (FIR) light generated at the (001) surface of a zincblende semiconductor is shown to derive principally from bulk difference‐frequency mixing. A strong modulation is observed for 1‐GW/cm2 pulses on InP, which demonstrates that the radiated FIR wave produced by bulk optical rectification is comparable to that generated by the transport of photoinjected carriers. Using the bulk rectification light as a clock, we show that more than 95% of the light produced from an InP (111) crystal by 100‐fs, 100‐μJ pulses is generated in a time shorter than the excitation pulse.

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The Behlen Observatory Variable Star Survey: Finding Charts And Light Curves For The First Ninety-Three Stars, Edward G. Schmidt, Darwin E. Reiswig Dec 1993

The Behlen Observatory Variable Star Survey: Finding Charts And Light Curves For The First Ninety-Three Stars, Edward G. Schmidt, Darwin E. Reiswig

Edward Schmidt Publications

In a previous paper, photometry for the first ninety-three stars in a photometric survey of variable stars was discussed. Finding charts, accurate coordinates, and light curves for those stars are presented here. The reliability of the coordinates from the General Catalogue of Variable Stars is discussed. The magnitude scale of the present photometry is compared with that of the Hubble Space Telescope Guide Star Catalogue.

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Far-Ultraviolet Stellar Photometry: A Field In Orion, Edward G. Schmidt, George R. Carruthers Dec 1993

Far-Ultraviolet Stellar Photometry: A Field In Orion, Edward G. Schmidt, George R. Carruthers

Edward Schmidt Publications

Far-ultraviolet photometry for 625 objects in Orion is presented. These data were extracted from electrographic camera images obtained during sounding rocket flights in 1975 and 1982. The 1975 images were centered close to the belt of Orion while the 1982 images were centered ~9° further north. One hundred and fifty stars fell in the overlapping region and were observed with both cameras. Sixty-eight percent of the objects were tentatively identified with known stars using the SIMBAD database while another 24% are blends of objects too close together to separate with our resolution. As in previous studies, the majority of the …

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The Effects Of Optical Feedback On Polarization Of Vertical Cavity Surface Emitting Lasers, Gregory J. Vansuch Dec 1993

The Effects Of Optical Feedback On Polarization Of Vertical Cavity Surface Emitting Lasers, Gregory J. Vansuch

Theses and Dissertations

Vertical Cavity Surface Emitting Lasers VCSELs are a type of semiconductor laser with a cavity oriented orthogonally to the planes of material growth. These lasers differ from conventional edge emitting lasers in several important ways. They have symmetric output beams and they are easily built into two dimensional arrays, making them very attractive as photonic components. The characteristic of interest in this thesis is polarization. While the asymmetric cavities of edge emitters exhibit a clear preference for light polarized in a particular direction, the cylindrically symmetric cavity of a VCSEL has no clear preference. Therefore, it should be relatively easy …

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Spectroscopic And Vibrational Energy Transfer Studies In Molecular Bromine, Courtney D. Holmberg Dec 1993

Spectroscopic And Vibrational Energy Transfer Studies In Molecular Bromine, Courtney D. Holmberg

Theses and Dissertations

Vibrational transfer and electronic quenching in the lower vibrational levels (v' < 3) of the B3π(0u+) state of 79Br2 were investigated using spectrally resolved, temporally resolved laser induced fluorescence techniques. Spectrally resolved emissions from collisionally populated Br2(B) vibrational levels were observed for Br2 and rare gas collision partners. Vibrational transfer was efficient in the non-predissociative vibrational levels and was adequately described by the Montroll-Shuler model for harmonic oscillators. A single fundamental rate coefficient for vibrational transfer from v' = 1 to v' = 0, kv(1,0), characterizes vibrational relaxation. For Br2, the …

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Infrared Fluorescence Studies Of Electronic-To-Vibrational Energy Transfer In A Br2:No System, Michael R. Hawks Dec 1993

Infrared Fluorescence Studies Of Electronic-To-Vibrational Energy Transfer In A Br2:No System, Michael R. Hawks

Theses and Dissertations

Steady-state photolysis techniques were used to study electronic-to- vibrational energy transfer mechanisms from atomic bromine to nitric oxide. Molecular bromine was photodissociated by 488nm radiation to produce equal parts Br(2P1/2) and Br(2P3/2). Side fluorescence intensity from Br(2P1/2) at 2.7 µm and from NO (v=1 and 2) around 5.3 µm measured as a function of bromine pressure and nitric oxide pressure. The branching ratio collisional transfer into the first and second states of NO was determined, and previously reported rates for quenching of NO by molecular bromine were verified.

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Predicting Nonlinear Time Series, James C. Gainey Jr. Dec 1993

Predicting Nonlinear Time Series, James C. Gainey Jr.

Theses and Dissertations

Predicting future values of a time series has many practical uses in real-time signal processing and understanding. This thesis implements an Adaptive Time Delay Neural Network ATNN capable of user-defined degeneration to the more common Time Delay Neural Network TDNN. Time delays along axons or at the synapses, which vary in biological systems, motivate this research. The ATNNTDNN test results and time series prediction capabilities are compared to those of the Real-Time Recurrent Learning RTRL algorithm. To show the advantages and disadvantages of using TDNN and ATNN for prediction versus the RTRL, the networks were applied to two problems incommensurate …

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Improved Quality Of Reconstructed Images Through Sifting Of Data In Statistical Image Reconstruction, Craig A. Stoudt Dec 1993

Improved Quality Of Reconstructed Images Through Sifting Of Data In Statistical Image Reconstruction, Craig A. Stoudt

Theses and Dissertations

The U.S. Air Force employs adaptive optics systems to produce images of exo-atmospheric objects. Typically, a large set of short exposure images are collected, re-centered to compensate for random image motion, averaged together to improve the signal to noise ratio, and then processed to form a reconstructed image. It is known that some short exposure images will be better than others, so some researchers have suggested that image quality can be improved by selecting a subset of the short exposure images according to some quality criterion, and then processing the average of this subset to form a single, high quality …

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A Non-Homogeneous, Spatio-Temporal, Wavelet Multiresolution Analysis And Its Application To The Analysis Of Motion, Thomas J. Burns Dec 1993

A Non-Homogeneous, Spatio-Temporal, Wavelet Multiresolution Analysis And Its Application To The Analysis Of Motion, Thomas J. Burns

Theses and Dissertations

This research presents a multiresolution wavelet analysis tool for analyzing motion in time sequential imagery. A theoretical framework is developed for constructing an L2R wavelet multiresolution analysis from three non-identical spatial and temporal L2R wavelet multiresolution analyses. This framework provides the flexibility to tailor the spatio-temporal frequency characteristics of the three dimensional wavelet filter to match the frequency behavior of the analyzed signal. An unconventional, discrete multiresolution wavelet decomposition algorithm is developed which yields a rich set of independent spatio-temporally oriented frequency channels for analyzing, the size and speed characteristics of moving objects. Unlike conventional wavelet decomposition methods, this algorithm …

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High Resolution Fourier Transform Absorption Spectrum Of 79Br2 B3Π(0U+) ← X1ΣG+, Robert E. Franklin Dec 1993

High Resolution Fourier Transform Absorption Spectrum Of 79Br2 B3Π(0U+) ← X1ΣG+, Robert E. Franklin

Theses and Dissertations

High Resolution Fourier Transform Spectroscopy has been conducted for the 79Br2 B3π(0u+) ← X1Σg+ system of 79Br2. A total of 64 vibrational levels, including v"= 0-3 and v' = 10-33, have been observed and assigned. Rotational levels as high as J=76 were observed. A global fitting routine has been developed to fit the rotational spectra to the Dunham Expansion. Using Bv and Dv for both the X and B state, rotational transitions were calculated to within 0. 02 cm-1. The expansions of …

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Characterization Of An Lcd For Use As A Programmable Phase Shifter To Produce A Single-Lobed Far-Field Pattern In A Phased Array, Gregory S. Kenyon Dec 1993

Characterization Of An Lcd For Use As A Programmable Phase Shifter To Produce A Single-Lobed Far-Field Pattern In A Phased Array, Gregory S. Kenyon

Theses and Dissertations

The liquid crystal display LCD from an inexpensive pocket television was converted to a spatial light modulator SLM for the purpose of altering the phase front of a ten element diode laser array to produce a single lobe far field pattern. Characterization of the SLM determined the amount of phase shift, amplitude modulation and polarization rotation properties. Nonuniformities within the phase shifter and insufficient phase shift prevented the formation of a single lobe. However, a very limited phase grating was created and analyzed. LCDs from inexpensive commercial pocket televisions were found unsuitable for use as phase shifting spatial light modulators.

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Performance Comparison Of Shearing Interferometer And Hartmann Wave Front Sensors, Timothy L. Pennington Dec 1993

Performance Comparison Of Shearing Interferometer And Hartmann Wave Front Sensors, Timothy L. Pennington

Theses and Dissertations

The resolution of optical imaging systems is severely degraded from the diffraction limit by the random effects of the atmosphere. Techniques exist to compensate for the atmospheric turbulence, one of which is adaptive optics. A critical component in the adaptive optics system is the wavefront sensor. Presently, two types of sensors are being used-the Hartmann-Shack Wavefront Sensor and the Shearing Interferometer. Previous studies have compared these two sensors and found them to perform identically for a point source. However, to date, no comparison has been performed for an extended source and subaperture spacing larger than the correlation length of the …

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Characterization Of Nonlinear Effects In Optically Pumped Vertical Cavity Surface Emitting Lasers, Scott L. Brown Dec 1993

Characterization Of Nonlinear Effects In Optically Pumped Vertical Cavity Surface Emitting Lasers, Scott L. Brown

Theses and Dissertations

The nonlinear characteristics of optically pumped Vertical Cavity Surface Emitting Lasers VCSELs are identified, isolated, and quantified. Three different VCSELs are evaluated including two with gain regions of bulk GaAs operating at 875nm and one multi-quantum well MQW InGaAs VCSEL operating at 950nm. The nonlinearities evaluated include those due to cavity temperature, carrier injection, and internal lasing field. The VCSELs are pumped by a picosecondfemtosecond TiSapphire laser which is configured to operate in CW, gated CW minimum gate width was 200ns, picosecond, and gated picosecond modes. A linear relationship is shown between wavelength and substrate temperature, cavity temperature, and injected …

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Optical Wavelet Transform For Fingerprint Identification, Robert P. Macdonald Dec 1993

Optical Wavelet Transform For Fingerprint Identification, Robert P. Macdonald

Theses and Dissertations

The Federal Bureau of Investigation FBI has recently sanctioned a wavelet fingerprint image compression algorithm developed for reducing storage requirements of digitized fingerprints. This research implements an optical wavelet transform of a fingerprint image, as the first step in an optical fingerprint identification process. Wavelet filters are created from computer generated holograms of biorthogonal wavelets, the same wavelets implemented in the FBI algorithm. Using a detour phase holographic technique, a complex binary filter mask is created with both symmetry and linear phase. The wavelet transform is implemented with continuous shift using an optical correlation between binarized fingerprints written on a …

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Experimental Verification Of Tomographic Reconstruction Of Turbulent Air Flow Structure Using Optical Wavefront Measurements, Bryon L. Pedersen Dec 1993

Experimental Verification Of Tomographic Reconstruction Of Turbulent Air Flow Structure Using Optical Wavefront Measurements, Bryon L. Pedersen

Theses and Dissertations

The performance of an aircraft based optical system is degraded by aero-optic turbulence. The varying index of refraction within the turbulent field causes phase perturbation in an optical wave. In order to compensate for aero-optic turbulence effects, the nature of the turbulence must be understood. Large scale, organized structure within the turbulence has been found to contribute significantly to the overall phase perturbation caused by a turbulent field. A unique approach was devised to determine the turbulence structure using tomographic reconstruction techniques. Tomography provides an excellent means to determine the underlying structure within a turbulent field. The tomographic reconstruction produces …

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A Theoretical Investigation Of Electrically Tunable Birefringent Optical Filters As The Special Discriminator In Hyperspectral Imaging Systems, Duane A. Sauve Dec 1993

A Theoretical Investigation Of Electrically Tunable Birefringent Optical Filters As The Special Discriminator In Hyperspectral Imaging Systems, Duane A. Sauve

Theses and Dissertations

This study investigated electrically tunable birefringent optical filters for use as the spectral discriminator in hyperspectral imaging systems. Spectral discrimination requirements for hyperspectral systems were defined using specification from two state-of-the-art hyperspectral imaging systems. The spectral discrimination requirements led to the definition of the ideal tunable optical filter for spectral discrimination purposes. Analytical and computer an analysis was performed for known birefringent filters which showed promise of electrical tunability excluding acousto-optic filters. No perfect match was found to the ideal tunable optical filter for hyperspectral imaging defined in this thesis. Both Lyot and Solc based filters exhibited two drawbacks for …

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Handwritten Word Recognition Based On Fourier Coefficients, Gary F. Shartle Dec 1993

Handwritten Word Recognition Based On Fourier Coefficients, Gary F. Shartle

Theses and Dissertations

A machine which can read unconstrained words remains an unsolved problem. For example, automatic entry o handwritten documents into a computer is yet to be accomplished. Most systems attempt to segment letters o a word and read words one character at a time. Segmenting a handwritten word is very difficult and often, the confidence of the results is low. Another method which avoids segmentation altogether is to treat each word as a whole. This research investigates the use of Fourier Transform coefficients, computed from the whole word, for the recognition of handwritten words. To test this concept, the particular pattern …

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