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Articles 6121 - 6150 of 6890
Full-Text Articles in Entire DC Network
Performance Analysis Of Doa Estimation Algorithms Using Physical Parameters, Hui Liu
Performance Analysis Of Doa Estimation Algorithms Using Physical Parameters, Hui Liu
Dissertations and Theses
Analytical performance analysis on Direction-Of-Arrival (DOA) estimation algorithms has attracted much excellent research in recent years, various statistical properties have been revealed. However, in most of these analyses, insights of the performance were masked because of the involvement of singular values and singular vectors which depend on the character of the algorithms and data structures in a complex and nonlinear manner.
Stratigraphy And Structure Of The Southeast Part Of The Portland Basin, Oregon, Kenneth E. Lite Jr.
Stratigraphy And Structure Of The Southeast Part Of The Portland Basin, Oregon, Kenneth E. Lite Jr.
Dissertations and Theses
The southeast part of the Portland Basin has been previously described by other investigators. However, little detailed information existed on the depositional relationships between the units, the various sedimentary fades, or the origin of many of the units.
Nonlinear Dynamics In Oscillating Waterfalls, Michael Schumann
Nonlinear Dynamics In Oscillating Waterfalls, Michael Schumann
Dissertations and Theses
The concern of this thesis was to investigate the nonlinear dynamics inherent in oscillating waterfalls.
Regional Tectonic Deformation Of The Northern Oregon Coast As Recorded By Pleistocene Marine Terraces, Richard Alan Mulder
Regional Tectonic Deformation Of The Northern Oregon Coast As Recorded By Pleistocene Marine Terraces, Richard Alan Mulder
Dissertations and Theses
Pleistocene marine terraces of the northern Oregon coast are an important factor in understanding the tectonics and paleoseismicity of the central Cascadia subduction zone. The lowest marine terrace, tentatively correlated to 80,000 year old Whiskey Run terrace of southern Oregon, is intermittently exposed in the present day sea cliff along an 80 km section of coastline between Tillamook Head and Cape Kiwanda. Terrace sediments consist largely of fine material such as clay, silt and fine sand with several locations containing large amounts of gravel derived from nearby headlands and steep bedrock hills. The terrace sediments are interpreted to be deposited …
Theoretical And Experimental Evaluation Of Hysteresis In Atmospheric Chemistry, Theodore Alan Haigh
Theoretical And Experimental Evaluation Of Hysteresis In Atmospheric Chemistry, Theodore Alan Haigh
Dissertations and Theses
This treatise is a recapitulation of the theoretical and experimental study of hysteresis in atmospheric kinetics. The original problem arose from a theoretical study of a series of reactions for clean air. Upon evaluation a bistable equilibrium was predicted. The steady-state analysis had delineated a metastable region for the set of reactions. This bounded region is the hysteresis that this research project evaluated.
Diffraction Of Light By A Focused Ultrasonic Wave, J. Huang, Joel Alan Nissen, Erik Bodegom
Diffraction Of Light By A Focused Ultrasonic Wave, J. Huang, Joel Alan Nissen, Erik Bodegom
Physics Faculty Publications and Presentations
The measurement of the acoustic pressure of a planar ultrasonic wave by light diffraction is well established. The ability to do similar measurements in the case of spherical waves has been doubted. However, we show that the range of validity can be extended to the focal region of a spherical concave piezoelectric transducer. Light is passed through the focal plane of a spherical concave transducer and is diffracted as a result of the variation in the index of refraction. The peak pressure can be calculated from the diffraction intensity by making the following simplification. We assume that in the focal …
Annual Faculty Senate Minutes October 1992 - June 1993, Portland State University Faculty Senate
Annual Faculty Senate Minutes October 1992 - June 1993, Portland State University Faculty Senate
Annual Compilations of the Faculty Senate Minutes (Minutes Only)
Minutes of the Faculty Senate for October 1992 to June 1993.
Porting Chorus To The Pa-Risc: Overall Evaluation, Jonathan Walpole, Marion Hakanson, Jon Inouye, Ravi Konuru
Porting Chorus To The Pa-Risc: Overall Evaluation, Jonathan Walpole, Marion Hakanson, Jon Inouye, Ravi Konuru
Computer Science Faculty Publications and Presentations
This document is part of a series of reports describing the design decisions made in porting the Chorus Operating System kernel to the Hewlett-Packard 9000 Series 800 workstation. This document summarizes the matches and mis-matches between Chorus and the PA-RISC and outlines the general lessons learned during the project.
This document is intended for people who are interested in (a) the separation of machinedependent micro-kernel code from machine-independent micro-kernel code, (b) the interaction between operating system design and the PA-RISC architecture, and (c) the portability ofthe Chorus operating system.
The first report in the series, Porting Chorus to the PA-RISe: …
Porting The Chorus Supervisor And Related Low-Level Functions To The Pa-Risc, Ravi Konuru, Marion Hakanson, Jon Inouye, Jonathan Walpole
Porting The Chorus Supervisor And Related Low-Level Functions To The Pa-Risc, Ravi Konuru, Marion Hakanson, Jon Inouye, Jonathan Walpole
Computer Science Faculty Publications and Presentations
This document is part of a series of reports describing the design decisions made in porting the Chorus Operating System to the Hewlett-Packard 9000 Series 800 workstation.
The Supervisor is the name given by Chorus to a collection of low-level functions that are machine dependent and have to be implemented when Chorus is ported from one machine to another. The Supervisor is responsible for interrupt, trap and exception handling, managing low-level thread initialization, context switch, kernel initialization, managing simple devices (timer and console) and offering a low-level debugger. This document describes the port of the Supervisor and related low-level functions. …
Porting Chorus To The Pa-Risc: Building, Debugging, Testing And Validation, Ravi Konuru, Marion Hakanson, Jon Inouye, Jonathan Walpole
Porting Chorus To The Pa-Risc: Building, Debugging, Testing And Validation, Ravi Konuru, Marion Hakanson, Jon Inouye, Jonathan Walpole
Computer Science Faculty Publications and Presentations
This document is part of a series of reports describing the design decisions made in porting the Chorus Operating System to the Hewlett-Packard 9000 Series 800 workstation. This document describes the environment for building the Chorus kernel, the various kernel tests, and the debugging environment used for porting the Chorus operating system to the HP PA-RISC.
The information contained in this paper will be of interest to people who wish to:
• Use the PA-Chorus kernel for development and/or modification, • Know about the build environment for Chorus kernel on PA-RISC, • Know about the PA-Chorus approach to debugging, • …
Ignoring Interprocessor Communication During Scheduling, Chintamani M. Patwardhan
Ignoring Interprocessor Communication During Scheduling, Chintamani M. Patwardhan
Dissertations and Theses
The goal of parallel processing is to achieve high speed computing by partitioning a program into concurrent parts, assigning them in an efficient way to the available processors, scheduling the program and then executing the concurrent parts simultaneously. In the past researchers have combined the allocation of tasks in a program and scheduling of those tasks into one operation. We define scheduling as a process of efficiently assigning priorities to the already allocated tasks in a program. Assignment of priorities is important in cases when more than one task at a processor is ready for execution. Most heuristics for scheduling …
A Multiple Coupled Microstrip Transmission Line Model For High-Speed Vlsi Interconnect Simulation, Lawrence Stevan Uzelac
A Multiple Coupled Microstrip Transmission Line Model For High-Speed Vlsi Interconnect Simulation, Lawrence Stevan Uzelac
Dissertations and Theses
A model is presented which incorporates the advantages of a mixed mode simulation to characterize transmission line behavior in multiple coupled Transmission line systems. The model is intended for use by digital circuit designers who wish to be able to obtain accurate transmission line behavior for complex digital systems for which continuous time simulation tools such as SPICE would be time prohibitive.
The model uses a transverse electromagnetic wave approximation to obtain solutions to the basic transmission line equations. A modal analysis technique is used to solve for the attenuation and propagation constants for the transmission lines. Modal analysis done …
Faculty Senate Monthly Packet December 1991, Portland State University Faculty Senate
Faculty Senate Monthly Packet December 1991, Portland State University Faculty Senate
Faculty Senate Monthly Packets
The December 1991 Monthly packet includes the December agenda and appendices and the Faculty Senate minutes and attachments from the meeting held November 1991.
Formation Of Positronium In E+ + H- Collisions, Jack C. Straton, Richard J. Drachman
Formation Of Positronium In E+ + H- Collisions, Jack C. Straton, Richard J. Drachman
Physics Faculty Publications and Presentations
Cross sections for positronium formation by capture from the negative hydrogen ion are given. Orthogonalization corrections to the Coulomb (first-order) Born approximation (CBA) differential and total cross sections are calculated using approximate H- wave functions of both Löwdin [Phys. Rev. 90, 123 (1953)] and Chandrasekhar [Astrophys. J. 100, 176 (1944)]. The present calculation of the CBA cross sections using the post interaction for Löwdin’s wave function (LCBAPS) disagrees with the calculation of Choudhury, Mukherjee, and Sural (CMS) [Phys. Rev. A 33, 2358 (1986)], whereas our results using the prior interaction agree. Thus, where CMS found an order …
Comparison Of Spice And Network C Simulation Models Using The Cam System, Wen-Tsung Yen
Comparison Of Spice And Network C Simulation Models Using The Cam System, Wen-Tsung Yen
Dissertations and Theses
The performance of SPICE and Network C (NC) circuit simulator when simulating MOS transistor circuits has been investigated and compared. SPICE analog model, NC analog model and NC MOS_PWL model are the three MOS transistor models being used. The comparison between SPICE and NC includes five areas. They are MOS transistor model, circuit analysis and computational methods, limitation on the ability to simulate circuits containing the MOS transistor diode configuration, run time and the ability to build new circuit component models using derived equations.
The prototype circuit being used is the Content-Addressable Memory (CAM) circuit. The CAM circuit is a …
Stochastic Hydrologic Modeling In Real Time Using A Deterministic Model (Streamflow Synthesis And Reservoir Regulation Model), Time Series Model, And Kalman Filter, Philip Kwok Fan Tang
Stochastic Hydrologic Modeling In Real Time Using A Deterministic Model (Streamflow Synthesis And Reservoir Regulation Model), Time Series Model, And Kalman Filter, Philip Kwok Fan Tang
Dissertations and Theses
The basic concepts of hydrologic forecasting using the Streamflow Synthesis And Reservoir Regulation Model of the U.S. Army Corps of Engineers, auto-regressive-moving-average time series models (including Greens' functions, inverse functions, auto covariance Functions, and model estimation algorithm), and the Kalman filter (including state space modeling, system uncertainty, and filter algorithm), were explored. A computational experiment was conducted in which the Kalman filter was applied to update Mehama local basin model (Mehama is a 227 sq. miles watershed located on the North Santiam River near Salem, Oregon.), a typical SSARR basin model, to streamflow measurements as they became available in simulated …
Limnology Of Two New Lakes, Mount St. Helens, Wa, Valerie Jean Kelly
Limnology Of Two New Lakes, Mount St. Helens, Wa, Valerie Jean Kelly
Dissertations and Theses
Coldwater Lake and Castle Lake are two new lakes which were formed in the aftermath of the volcanic eruption of Mount St. Helens, WA in May, 1980. This research describes the limnology of these lakes ten years later, and includes physical, chemical, and biological parameters. The two lakes are compared and contrasted. Previous research on the eruption and its aftermath, as well as earlier studies of the lakes are described.
Faculty Senate Monthly Packet November 1991, Portland State University Faculty Senate
Faculty Senate Monthly Packet November 1991, Portland State University Faculty Senate
Faculty Senate Monthly Packets
The November 1991 Monthly packet includes the November agenda and appendices and the Faculty Senate minutes and attachments from the meeting held October 1991.
Green's Law Revisited: Tidal Long-Wave Propagation In Channels With Strong Topography, David A. Jay
Green's Law Revisited: Tidal Long-Wave Propagation In Channels With Strong Topography, David A. Jay
Civil and Environmental Engineering Faculty Publications and Presentations
Green's Law states that tidal long-wave elevation ζ and tidal transport Q vary with width b and depth h according to ζ ≌ b−1/2h−1/4 and Q ≌ b+1/2h+/4. This solution is of limited utility because it is restricted to inviscid, infinitesimal waves in channels with no mean flow and weak topography (those with topographic scale L ≫ wavelength λ). An analytical perturbation model including finite-amplitude effects, river flow, and tidal flats has been used to show that (1) wave behavior to lowest order is a function of only two nondimensional parameters representing, respectively, …
Constrained-Latency Storage Access: A Survey Of Application Requirements And Storage System Design Approaches, Richard Staehli, Jonathan Walpole
Constrained-Latency Storage Access: A Survey Of Application Requirements And Storage System Design Approaches, Richard Staehli, Jonathan Walpole
Computer Science Faculty Publications and Presentations
Applications with Constrained Latency Storage Access (CLSA) are those that have large storage needs and hard constraints on the amount of latency they can tolerate. Such applications present a problem when the storage technology that is cost effective and large enough cannot meet their latency constraints for demand fetching. Examples are found in the developing field of multimedia computing and, to a lesser extent, in real-time database literature. This paper examines the nature of timing constraints at the application-storage interface and defines a classification for both the synchronization constraints of the application and the latency characteristics of the storage system. …
Field-Equation Approximations And Amplification In High-Gain Lasers: Numerical Results, Lee W. Casperson
Field-Equation Approximations And Amplification In High-Gain Lasers: Numerical Results, Lee W. Casperson
Electrical and Computer Engineering Faculty Publications and Presentations
It has recently been shown that a field-equation time-derivative approximation that is commonly used in studies of laser-oscillator dynamics is not necessary and can lead to significant errors for some lasers. A related space-derivative approximation is widely used in studies of steady-state laser amplifiers. A more rigorous amplifier formalism is developed here, and the results are exact solutions of Maxwell’s equations. The improved model predicts a spatial instability, single mirror oscillation, and other interesting field behavior.
Field-Equation Approximations And Amplification In High-Gain Lasers: Analytical Results, Lee W. Casperson
Field-Equation Approximations And Amplification In High-Gain Lasers: Analytical Results, Lee W. Casperson
Electrical and Computer Engineering Faculty Publications and Presentations
In a related study the equations governing a high-gain laser amplifier have been solved numerically without making the usual slowly-varying-amplitude derivative approximation in Maxwell’s equations, and thus the field amplitudes are not restricted to vary negligibly in a distance of one wavelength. The results reveal an instability that involves reflections and oscillatory growth of perturbations away from steady state. In the present study steady-state solutions of the field equations are obtained analytically, and transformations are described for converting the equations to alternative intensity-equation sets. These intensity equations are linearized and solved for the growth rate and oscillation period of the …
An Experimental Investigation Of The Finite Time Efficiency Of A Peltier Refrigeration Device, Thomas Schneider
An Experimental Investigation Of The Finite Time Efficiency Of A Peltier Refrigeration Device, Thomas Schneider
Dissertations and Theses
Since the need of energy conservation has become more and more urgent in the past decades, there has been an increased interest in the study and development of more efficient energy conversion systems. One of the fields that have arisen from that endeavor is a branch of physics called Finite Time Thermodynamics (FIT). It may be said that FIT was initiated through the famous paper by Curzon and Ahlborn (1975) that established new bounds on the efficiency of a finite time Carnot heat engine. Before, the traditional treatments gave a fundamental upper limit on the efficiency of any heat engine. …
Hydrogeology Of An Alluvial Aquifer In The Blue Lake Area, East Multnomah County, Oregon, James Mitchell Wilkinson
Hydrogeology Of An Alluvial Aquifer In The Blue Lake Area, East Multnomah County, Oregon, James Mitchell Wilkinson
Dissertations and Theses
This thesis evaluates the hydraulic relationship between the Blue Lake gravel aquifer, the Columbia River, and Blue Lake. Hydrogeology, water levels, and stable isotopes were used to establish these hydraulic relationships.
Frequency Shifts Of Molecules At Rough Metal Surfaces, M. H. Hider, P.T. Leung
Frequency Shifts Of Molecules At Rough Metal Surfaces, M. H. Hider, P.T. Leung
Physics Faculty Publications and Presentations
The frequency shifts for dipolar transitions of molecules at rough metallic surfaces are studied in a phenomenological model following the approach of the authors' previous work [Phys. Rev. B 36, 4664 (1987)], with the surface roughness modeled by a shallow grating profile in most cases. The main findings here are as follows: (1) such surface-induced shifts are indeed observable for molecular frequencies away from the surface-plasmon resonance frequency of the metal; (2) the presence of surface roughness can either enhance or suppress the flat-surface-induced shifts, leading to extra morphology-dependent resonances originated from the radiative coupling between the molecular emission and …
An Information Theoretic Framework For Exploratory Multivariate Market Segmentation Research, Jamshid C. Hosseini, Robert R. Harmon, Martin Zwick
An Information Theoretic Framework For Exploratory Multivariate Market Segmentation Research, Jamshid C. Hosseini, Robert R. Harmon, Martin Zwick
Complex Systems Faculty Publications and Presentations
State-of-the-art market segmentation often involves simultaneous consideration of multiple and overlapping variables. These variables are studied to assess their relationships, select a subset of variables which best represent the subgroups (segments) within a market, and determine the likelihood of membership of a given individual in a particular segment. Such information, obtained in the exploratory phase of a multivariate market segmentation study, leads to the construction of more parsimonious models. These models have less stringent data requirements while facilitating substantive evaluation to aid marketing managers in formulating more effective targeting and positioning strategies within different market segments. This paper utilizes the …
Fock-Tani Hamiltonian For Reactions Involving Two-Electron Atoms, Jack C. Straton
Fock-Tani Hamiltonian For Reactions Involving Two-Electron Atoms, Jack C. Straton
Physics Faculty Publications and Presentations
The Fock-Tani Hamiltonian is found for scattering processes involving up to two ions and two electrons. Possible bound-state species include one or two electrons bound on an ion fixed at the origin, and a one-electron projectile atom. A diagrammatic technique is illustrated that simplifies the algebra of the transformation. Coulomb- or plane-wave states are automatically generated by the same asymptotic Hamiltonian for all arrangement channels.
Behavior Of An Ion In A Bubble In The Ground State, Joung Hoon Oh
Behavior Of An Ion In A Bubble In The Ground State, Joung Hoon Oh
Dissertations and Theses
Deuterons might be trapped in a bubble embryo which occur s due to statistical fluctuation in heavy water. The size of the bubble embryo is expected to be an order of a small molecule. The ground state energy level which the deuteron may occupy in the bubble is calculated by solving the Schroedinger equation, and by considering the interaction between the trapped deuteron by a spherical bubble and the surrounding polarized liquid medium (heavy water). From the dependence of the energy eigenvalue of the ground state on the bubble radius, the pressure exerted on the bubble wall is obtained. It …
The Dimension Of A Chaotic Attractor, Roslyn Gay Lindquist
The Dimension Of A Chaotic Attractor, Roslyn Gay Lindquist
Dissertations and Theses
Tools to explore chaos are as far away as a personal computer or a pocket calculator. A few lines of simple equations in BASIC produce fantastic graphic displays. In the following computer experiment, the dimension of a strange attractor is found by three algorithms; Shaw's, Grassberger-Procaccia's and Guckenheimer's. The programs were tested on the Henon attractor which has a known fractal dimension. Shaw's and Guckenheimer's algorithms were tested with 1000 data points, and Grassberger's with 100 points, a data set easily handled by a PC in one hour or less using BASIC or any other language restricted to 640K RAM. …
Interpretation Of The Thermal Behavior Of Groundwater In An Alluvial Terrace: Bonneville Dam, Columbia Gorge, Oregon, Richard Stephen Malin
Interpretation Of The Thermal Behavior Of Groundwater In An Alluvial Terrace: Bonneville Dam, Columbia Gorge, Oregon, Richard Stephen Malin
Dissertations and Theses
Groundwater temperature data, collected at an alluvial terrace located on the Oregon shore of the Columbia River downstream from Bonneville Darn, was analyzed in order to characterize and formulate a conceptual model of the thermal data for the groundwater system in the terrace. There is concern that an unlined entrance channel for a new navigation lock, to be located down the middle of the terrace, will widen the range of temperatures in the fish hatchery-groundwater supply. The analysis of temperature behavior in the terrace supports the hydraulic observations derived from analysis of pump test data, but with greater definition of …