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Articles 6271 - 6300 of 6890
Full-Text Articles in Entire DC Network
Ionization Of K-Shell Electrons By Highly Relativistic Protons, M. L. Rustgi, P.T. Leung, S. A. Long
Ionization Of K-Shell Electrons By Highly Relativistic Protons, M. L. Rustgi, P.T. Leung, S. A. Long
Physics Faculty Publications and Presentations
A comparative study of three decent theoretical formalisms by Anholt, Scofield, Becker, and coworkers (1978-85) for K-shell ionization by highly relativistic protons has been carried out. The importance of the spin-flip mechanism is emphasized. It is concluded that in the analysis of such inner-shell ionization processes, an accurate description of the projectile-target interaction is of much more significance than the accuracy of the wave functions of the atomic electrons.
Limitation Of The Semirelativistic Approach In Sum Rules And Related Calculations In Atomic Physics, M. L. Rustgi, P.T. Leung, S. A. Long
Limitation Of The Semirelativistic Approach In Sum Rules And Related Calculations In Atomic Physics, M. L. Rustgi, P.T. Leung, S. A. Long
Physics Faculty Publications and Presentations
It is shown that the semirelativistic approach, when applied consistently to atomic calculations involving the Thomas-Reiche-Kuhn sum rule or its applications, may lead to very inaccurate results.
Portland State Magazine, Portland State University. Office Of University Communications
Portland State Magazine, Portland State University. Office Of University Communications
Portland State Magazine
PSU’s alumni magazine, published quarterly. In this issue: PSU faculty experience Middle Eastern and North African cultures through study-travel program; joint program encourages ethnic minorities to become teachers; Portland’s reputation for racist violence; and more.
Fractional Representation Design Of Dynamic Output Controllers For Multiple Time Scale Systems, Robert Stephen Jaffe
Fractional Representation Design Of Dynamic Output Controllers For Multiple Time Scale Systems, Robert Stephen Jaffe
Dissertations and Theses
This dissertation addresses the design of controllers for multi variable finite-dimensional, linear, autonomous dynamical systems with distinct sets of slow and fast dynamics, which thus display multiple time scale behavior. It seeks, specifically, to compose overall controllers from lower-order dynamic output compensators, which are designed separately for slow and fast approximating models of the given plant. Reduction of the dynamic order of the design problem and the avoidance of numerically ill-conditioned interaction between modes of disparate orders of magnitude are among the patent advantages which pertain to such a design. As is well known, the explicit singularly perturbed systems, as …
Medium Resolution Atmospheric Pressure Ionization Mass Spectrometer, Andrew H. Grange, Robert J. O'Brien, Douglas F. Barofsky
Medium Resolution Atmospheric Pressure Ionization Mass Spectrometer, Andrew H. Grange, Robert J. O'Brien, Douglas F. Barofsky
Chemistry Faculty Publications and Presentations
An atmospheric pressure ionization (API) source for a VG 7070E‐HF mass spectrometer has been built and successfully operated at an accelerating potential of 6 kV. Hydrated protons and hydrated organic ions formed in the API source can be either partially or completely disaggregated by collisionally induced dissociation before entering the mass analyzer. The protonated molecular ions of pinacolone and 2,4‐pentanedione can be fully separated (R=2800, m/z 101,
Voltage Controlled Resistance Model For Mos Transistors, Joey Zong-Yi Jia
Voltage Controlled Resistance Model For Mos Transistors, Joey Zong-Yi Jia
Dissertations and Theses
The voltage controlled resistance model is developed for a reliable MOS transistor resistance mapping. The model includes both system and local parameters, and incorporates the effect of rise and fall time variations on the gate delay. MOS transistor resistance mapping is applied in logic simulation and timing verification. Also, it can be used in automatic transistor sizing and critical path analysis.
Safety Related Model And Studies Of Trojan Nuclear Power Plant Electrical Distribution System, Hamidreza Sharifnia
Safety Related Model And Studies Of Trojan Nuclear Power Plant Electrical Distribution System, Hamidreza Sharifnia
Dissertations and Theses
The most important requirement for running a nuclear power plant safely is having a reliable safety system, especially during the emergency shutdown condition. For performing a scrutiny load flow and voltage drop study a detailed and comprehensive electrical model for the emergency electrical distribution system of the Trojan Nuclear Power Plant has been developed. This model includes the representation of the transformers, circuit breakers, motors, cables and load data from 4160 volts level down to the individual 480 volts loads.
Rock Slope Stability Studies In Siskiyou National Forest, Greg Visconty
Rock Slope Stability Studies In Siskiyou National Forest, Greg Visconty
Dissertations and Theses
The line mapping method of Piteau and Martin (1977) was tested on two different rock type road cuts in the Siskiyou National Forest, and was found to be an efficient means of collecting geological data for rock slope stability analysis. The unbiased approach of this method calls for close scrutiny of the outcrops in question, covering more ground than other methods in less time. In turn, this close attention to every crack in the outcrop reveals more about the stability of the slope, and can reveal hidden hazards of rock fall.
The supportive systems for analyzing the data - stereonets …
Metasomatism Between Amphibolite And Metaultramafic Rocks During Upper Amphibolite Facies Metamorphism, Tobacco Root Mountains, Southwest Montana, William Robert Mcculloch
Metasomatism Between Amphibolite And Metaultramafic Rocks During Upper Amphibolite Facies Metamorphism, Tobacco Root Mountains, Southwest Montana, William Robert Mcculloch
Dissertations and Theses
The purpose of this study is to characterize the metasomatism that has taken place as a result of the chemical incompatibility between mafic and metaultramafic bulk compositions during high-grade regional metamorphism in the Tobacco Root Mountains, southwest Montana. Metasomatism of these rocks took place by both diffusionand infiltration-dominated processes. The result of these processes are characterized mineralogically and geochemically in the rocks.
Discharge Suppression System For A Double Focusing, Atmospheric Pressure Ionization Mass Spectrometer, Andrew H. Grange, Robert J. O'Brien, Douglas F. Barofsky
Discharge Suppression System For A Double Focusing, Atmospheric Pressure Ionization Mass Spectrometer, Andrew H. Grange, Robert J. O'Brien, Douglas F. Barofsky
Chemistry Faculty Publications and Presentations
An electrical discharge suppression system for a medium throughput (∼2 l/s) pumping line has been devised that works up to potentials of ±15 kV. This device permits atmospheric pressure ionization sources to be interfaced to high-resolution, magnetic sector mass spectrometers with source potentials of 6-10 kV
Pupil Mobility And Its Effect On Basic Skills Achievement Growth Rates And The Educational Program, Daniel P. Klee
Pupil Mobility And Its Effect On Basic Skills Achievement Growth Rates And The Educational Program, Daniel P. Klee
Dissertations and Theses
The purpose of the study was to compare the basic skills achievement scores of mobile and non-mobile students within the Portland Public Schools. The problem was to assess the effect of this mobility on basic skills achievement and the total educational program. The study was designed to test differences in reading, language usage and mathematics achievement test scores between pupils in the third through the eighth grades. The instrument that was used was the Portland Achievement Levels Tests of reading, language usage and math. These tests are administered to students in grades 3 - 8 in the fall and spring …
A Study Of Principals' Leadership Behavior In One Suburban School District, Darleen Huber-Dilbeck
A Study Of Principals' Leadership Behavior In One Suburban School District, Darleen Huber-Dilbeck
Dissertations and Theses
The purpose of this study was to investigate the leadership behavior of principals as perceived by the teachers and principals of one suburban school district. Research questions asked were: (1) Are there significant differences between the perceptions of principals and teachers concerning principals' leadership behavior on the twelve subscales of the LBDQ-XII? (2) Are there significant differences in viewing the leadership role when teachers' age, gender, teaching experience, level of training, or teaching assignment is considered?
This descriptive study invited 350 randomly selected teachers and all of the principals from 35 elementary, intermediate, and high schools in one suburban school …
Faculty Senate Monthly Packet December 1987, Portland State University Faculty Senate
Faculty Senate Monthly Packet December 1987, Portland State University Faculty Senate
Faculty Senate Monthly Packets
The December 1987 Monthly packet includes the December agenda and appendices and the Faculty Senate minutes and attachments from the meeting held November 1987.
Faculty Senate Monthly Packet November 1987, Portland State University Faculty Senate
Faculty Senate Monthly Packet November 1987, Portland State University Faculty Senate
Faculty Senate Monthly Packets
The November 1987 Monthly packet includes the November agenda and appendices and the Faculty Senate minutes and attachments from the meeting held October 1987.
Pulse-Train Instabilities In A Mode-Locked Argon Laser: Experimental Studies, Duncan Leo Macfarlane, Lee W. Casperson
Pulse-Train Instabilities In A Mode-Locked Argon Laser: Experimental Studies, Duncan Leo Macfarlane, Lee W. Casperson
Electrical and Computer Engineering Faculty Publications and Presentations
The output train of pulses from an acousto-optically mode-locked argon-ion laser was studied as a function of the loss modulation frequency for small detunings from the optimum c/2L modulation. A shift away from the optimum frequency by as little as 1 part in 10⁴ was found to produce several strong lower-frequency components that amplitude modulate the mode-locked pulse train. Notably, the strongest subharmonic is a frequency near ƒopt/4. Further detuning results in an irregular, slow (of the order of 10⁵ Hz) amplitude envelope on the pulse train. The homodyne spectrum of this phase of operation represents a progressive filling-in behavior …
Classifying Oregon Lake-Watershed Ecosystems For Regional Water Resources Assessment, Randall Alan Jones
Classifying Oregon Lake-Watershed Ecosystems For Regional Water Resources Assessment, Randall Alan Jones
Dissertations and Theses
Natural lake-watershed ecosystems in Oregon compose a diverse and valuable assemblage of land and water resources. With an increasing demand on lakes for recreation, water supplies, and aesthetic values and an increase in available data on Oregon lake systems, there is a need for applicable and timely scientific water management information about lake conditions statewide. This thesis is an attempt to summarize some of the data collected on natural Oregon lake-watershed ecosystems.
The purpose of the thesis is to identify the most typical natural systems out of an initial data base of twenty-four variables, measured over ninety-eight lake-watershed ecosystems. The …
Portland State Magazine, Portland State University. Office Of University Communications
Portland State Magazine, Portland State University. Office Of University Communications
Portland State Magazine
PSU’s alumni magazine, published quarterly. In this issue: for composer Tomas Svoboda, life has been leading slowly, but joyfully, toward international stature; Under the direction of Arthur Emlen, PSU’s human services research has had national impact; Mary Lou Webb, Class of ’69, comes back to the University to guide alumni programs; and more.
Energy-Transfer Theory For The Classical Decay Rates Of Molecules At Rough Metallic Surfaces, P.T. Leung, Thomas F. George
Energy-Transfer Theory For The Classical Decay Rates Of Molecules At Rough Metallic Surfaces, P.T. Leung, Thomas F. George
Physics Faculty Publications and Presentations
The problem of the decay rates for molecules at rough metallic surfaces is considered, where the classical electromagnetic energy-transfer theory of Chance, Prock, and Silbey for a flat surface is generalized to the case of a rough boundary. A dynamical theory is constructed through the combination of the Sommerfeld antenna theory and the integral equation formalism of Maxwell's equations at rough boundaries established mainly by Maradudin, Mills, and Agarwal. Perturbative solutions are obtained and numerical results are given with reference to a shallow sinusoidal grating surface. The results, when compared with those obtained previously from the application of the image …
Geomorphic Character, Age And Distribution Of Rock Glaciers In The Olympic Mountains, Washington, Steven Paul Welter
Geomorphic Character, Age And Distribution Of Rock Glaciers In The Olympic Mountains, Washington, Steven Paul Welter
Dissertations and Theses
Rock glaciers are tongue-shaped or lobate masses of rock debris which occur below cliffs and talus in many alpine regions. They are best developed in continental alpine climates where it is cold enough to preserve a core or matrix of ice within the rock mass but insufficiently snowy to produce true glaciers. Previous reports have identified and briefly described several rock glaciers in the Olympic Mountains, Washington, but no detailed integrative study has been made regarding the geomorphic character, age, and distribution of these features.
The purpose of this study is two-fold. First, surface sediment fabric analysis and relative and …
Molecular Lifetimes In The Presence Of Periodically Roughened Metallic Surfaces, P.T. Leung, Z. C. Wu, Daniel A. Jelski, Thomas F. George
Molecular Lifetimes In The Presence Of Periodically Roughened Metallic Surfaces, P.T. Leung, Z. C. Wu, Daniel A. Jelski, Thomas F. George
Physics Faculty Publications and Presentations
The lifetimes of molecules located close to a sinusoidal grating surface are studied within a classical phenomenological model. The contribution of surface roughness to the molecular decay rate is attributed to the discrepancy between the experiments of Rossetti and Brus and the theory of Chance, Prock, and Silbey. It is found that surface roughness can either enhance or diminish the flat-surface value for the decay rate depending on the emitting frequency, molecule-surface distance, and the molecular orientation.
Explosion Structures In Grande Ronde Basalt Of The Columbia River Basalt Group, Near Troy, Oregon, Leonard Lee Orzol
Explosion Structures In Grande Ronde Basalt Of The Columbia River Basalt Group, Near Troy, Oregon, Leonard Lee Orzol
Dissertations and Theses
Explosion structures occur in flows of Grande Ronde Basalt in the study area near Troy, Oregon. Data from nineteen stratigraphic sites indicate that the maximum number of flows that contain explosion structures at any one site is six. In the informally named Troy flow, explosion structures are widespread.
Each flow that contains explosion structures can be divided into two cooling units. The first cooling units occupy troughs in the pre-eruption topography and are up to 10 meters thick. The second cooling units contain the explosion structures and are up to 100 meters thick. The thickness of flows that contain explosion …
Faculty Senate Monthly Packet June 1987, Portland State University Faculty Senate
Faculty Senate Monthly Packet June 1987, Portland State University Faculty Senate
Faculty Senate Monthly Packets
The June 1987 Monthly packet includes the June agenda and appendices and the Faculty Senate minutes and attachments from the meeting held May 1987.
Social Traps And Environmental Policy, Robert Costanza
Social Traps And Environmental Policy, Robert Costanza
Institute for Sustainable Solutions Publications and Presentations
In recent years, scientific understanding and public awareness of environmental problems have increased tremendously. Yet our ability to manage these problems effectively has in too many cases gotten worse, not better. By studying real-world social traps and laboratory examples, we can learn effective escapes.
Faculty Senate Monthly Packet May 1987, Portland State University Faculty Senate
Faculty Senate Monthly Packet May 1987, Portland State University Faculty Senate
Faculty Senate Monthly Packets
The May 1987 Monthly packet includes the May agenda and appendices and the Faculty Senate minutes and attachments from the meeting held April 1987.
Reduced-Mass Fock-Tani Representations For A+ + (B+C-) --> (A+C-) + B+ And First-Order Results For {Abc} = {Ppe, Epe, Μpμ, Μdμ, And Μtμ}, Jack C. Straton
Reduced-Mass Fock-Tani Representations For A+ + (B+C-) --> (A+C-) + B+ And First-Order Results For {Abc} = {Ppe, Epe, Μpμ, Μdμ, And Μtμ}, Jack C. Straton
Physics Faculty Publications and Presentations
The Fock-Tani transformation in the Jacobi three ⟶ two-body reduced-mass system is carried out and the first-order T matrix is found to be identical to that for the full three-body transformation. The Fock-Tani transformation in the reduced-mass system in which particle b is fixed at the origin is found to give a first-order T matrix with an error of mc /mb in the initial momentum wave function. First-order differential and total cross sections are calculated for a+ + (b+c-)⟶(a+c-) + b+ where |abc|= { …
Rheologic Properties And Kinematics Of Emplacement Of The Chaos Jumbles Rockfall Avalanche, Lassen Volcanic National Park, California, Dean B. Eppler, Jonathan H. Fink, Raymond Fletcher
Rheologic Properties And Kinematics Of Emplacement Of The Chaos Jumbles Rockfall Avalanche, Lassen Volcanic National Park, California, Dean B. Eppler, Jonathan H. Fink, Raymond Fletcher
Geology Faculty Publications and Presentations
The Chaos Jumbles is a rockfall avalanche deposit that was emplaced by three separate events ~ 300 years ago. Deposits from each event are distinguishable on the basis of morphology, size variation of large dacitic surface clasts, and by the color of both the matrix and entrained dacitic blocks. Steep lateral and distal deposit margins and surface features such as folds and apparent strike-slip faults indicate that each rockfall avalanche had a finite yield strength and was being actively deformed and sheared throughout the body of the moving deposit, rather than strictly along a basal surface. Kinematic analysis of the …
Fourier Transform Of The Product Of N One-Center Hydrogenic Orbitals, Jack C. Straton
Fourier Transform Of The Product Of N One-Center Hydrogenic Orbitals, Jack C. Straton
Physics Faculty Publications and Presentations
Integrating the radial part of the Fourier transform of the product of N hydrogenic orbitals results in an associated Legendre function that can be reduced to a finite series of elementary functions. This transform is found to depend on a polynomial in the wave vector k divided by a binomial in k2 raised to a power that is the sum of principle quantum numbers. This form facilitates the analytical reduction of integrals arising from orthogonalization corrections in atomic processes. Transforms for the product of orbital pairs (1s,1s) through (1s,3d) are given …
Simulation Modeling On The Macintosh Using Stella, Robert Costanza
Simulation Modeling On The Macintosh Using Stella, Robert Costanza
Institute for Sustainable Solutions Publications and Presentations
STELLA (Structured Thinking Experimental Learning Laboratory with Animation) is a computer application for Macintosh that allows model building for the biologist.
Faculty Senate Monthly Packet January 1987, Portland State University Faculty Senate
Faculty Senate Monthly Packet January 1987, Portland State University Faculty Senate
Faculty Senate Monthly Packets
The January 1987 Monthly packet includes the January agenda and appendices and the Faculty Senate minutes and attachments from the meeting held December 1986.
Stratigraphic And Geochemical Evolution Of The Glass Buttes Complex, Oregon, Richard Louis Roche
Stratigraphic And Geochemical Evolution Of The Glass Buttes Complex, Oregon, Richard Louis Roche
Dissertations and Theses
Glass Buttes complex lies at the northern margin of the Basin and Range province in central Oregon and is cut by the northwest-trending Brothers fault zone. An older acrystalline volcanic sequence of high-silica rhyolites (>75% SiO2) forms a broad platform composed of domes and flows with minor pyroclastic deposits. The high-silica rhyolite sequence is divided on the basis of texture into 1) zoned flows and domes, 2) obsidian flows, 3) felsite flows, and 4) biotite-phyric flows and domes.