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Articles 6511 - 6540 of 6889
Full-Text Articles in Entire DC Network
Rheological Properties Of Mudflows Associated With The May 1980 Eruptions Of Mount St. Helens Volcano, Washington, Jonathan H. Fink, Michael C. Malin, Richard E. D'Alli, Ronald Greeley
Rheological Properties Of Mudflows Associated With The May 1980 Eruptions Of Mount St. Helens Volcano, Washington, Jonathan H. Fink, Michael C. Malin, Richard E. D'Alli, Ronald Greeley
Geology Faculty Publications and Presentations
Rheological properties of three recent mudflows at Mount St. Helens were estimated using techniques developed for determining the properties of debris flows based on the geometry of their deposits. Calculated yield strengths of 1100, 1000, and 400 Pa, maximum flow velocities of 10 to 31 m/s, volumetric flow rates of 300 to 3400 m3/s, and plastic viscosities of 20 to 320 Pa-s all compare favorably with measured and estimated values cited in the literature. A method for determining likely sites of future mudflow initiation based on these data is outlined.
Approximate Reasoning, Logics For Self-Reference, And The Use Of Nonclassical Logics In Systems Modeling, Daniel Guy Schwartz
Approximate Reasoning, Logics For Self-Reference, And The Use Of Nonclassical Logics In Systems Modeling, Daniel Guy Schwartz
Dissertations and Theses
This work advances the use of nonclassical logics for developing qualitative models of real-world systems. Abstract mathematics is "qualitative" inasmuch as it relegates numerical considerations to the background and focuses explicitly on topological, algebraic, logical, or other types of conceptual forms. Mathematical logic, the present topic, serves to explicate alternative modes of reasoning for use in general research design and in model construction. The central thesis is that the theory of formal logical systems, and particularly, of logical systems based on nonclassical modes of reasoning, offers important new techniques for developing qualitative models of real-world systems. This thesis is supported …
Police Patrol Deployment In Small Urban Centers: An Application Of Integrated Management Decision-Making, Robert Wayne Taylor
Police Patrol Deployment In Small Urban Centers: An Application Of Integrated Management Decision-Making, Robert Wayne Taylor
Dissertations and Theses
This dissertation was undertaken to examine and review the theoretical issues concerning decision-making. From this analysis, a new and innovative technique for problem-solving was developed, entitled Integrated Management Decision-making. The underlying theoretical framework of this model involved the integration of the organization and the environment. Political, economic, social, cultural, and other community factors were discussed as major influences in the decision-making process. Integrated Management Decision-Making was derived from the combination of four existing theoretical perspectives: (1) decision-making is a process; (2) decision-making involves the ability to make rational choices; (3) decision-making involves the ability to make rational choices; (3) decision-making …
Dialectical Thermodynamics, Martin Zwick
Dialectical Thermodynamics, Martin Zwick
Complex Systems Faculty Publications and Presentations
A lugubrious, though highly abstract, proposition about sociocultural systems is suggested by a union of dialectical and thermodynamic concepts: systems are invariably flawed, not only because of poor --or absence of -design, or ill will, but because the "closedness" of a system necessarily wars on its "openness," and because the actualization of the organizing principle upon which a system is based brings with it the development of its "shadow," its negation. Reconciliation of these contradictions is not assured.
Geophysical And Geochemical Analyses Of Selected Miocene Coastal Basalt Features, Clatsop County, Oregon, Virginia Josette Pfaff
Geophysical And Geochemical Analyses Of Selected Miocene Coastal Basalt Features, Clatsop County, Oregon, Virginia Josette Pfaff
Dissertations and Theses
The proximity of Miocene Columbia River basalts to the "locally-erupted" coastal Miocene basalts in northwestern Oregon, and the compelling similarities between the two groups, suggest that the coastal basalts, rather than being locally erupted, may be the westward extension of plateau basalts derived from eastern Oregon and Washington.
The local-origin hypothesis is based largely on the interpretation of coastal dikes and sills as representing vent areas; however, a complex mechanism, as yet unsatisfactorily defined, would be required to cause the eruption of virtually identical magmas simultaneously from source areas 500 km apart.
This study, therefore, has investigated the coastal basalt …
Stopping Power Of Matter For Alpha Particles At Extreme Relativistic Energies, P.T. Leung, M. L. Rustgi, J. E. Turner
Stopping Power Of Matter For Alpha Particles At Extreme Relativistic Energies, P.T. Leung, M. L. Rustgi, J. E. Turner
Physics Faculty Publications and Presentations
The stopping power of matter for alpha particles at extreme relativistic energies has been calculated by incorporating the charge form factor. A table is presented for aluminum, copper, and lead. It is found that at the highest energies considered, inclusion of form factor reduces the mass stopping power by about 6-8% in comparison with that predicted by Bethe's relativistic formula.
Faculty Senate Monthly Packet December 1980, Portland State University Faculty Senate
Faculty Senate Monthly Packet December 1980, Portland State University Faculty Senate
Faculty Senate Monthly Packets
The December 1980 Monthly packet includes the December agenda and appendices and the Faculty Senate minutes and attachments from the meeting held November 1980.
Dielectric Saturation In Dipolar Fluids. I. The Single-Molecule Distribution Function, John D. Ramshaw
Dielectric Saturation In Dipolar Fluids. I. The Single-Molecule Distribution Function, John D. Ramshaw
Physics Faculty Publications and Presentations
The functional-derivative formalism is used to investigate the form of the equilibrium single-molecule distribution function n(1) in a finite fluid system of rigid polar molecules subjected to a strong external electric field that varies slowly with position. The investigation is based on the assumption that the long-range asymptotic behavior of the direct correlation function is independent of the external field, and is hence the same as in the unperturbed fluid. This assumption implies that n(1) has the form of a single-molecule Boltzmann factor in which the interaction energy is that of a deformable quasidipole with the local Lorentz electric field …
Electrostatic Tem Studies Of Magnetic Domains In Thin Iron Films, Hideaki Karamon
Electrostatic Tem Studies Of Magnetic Domains In Thin Iron Films, Hideaki Karamon
Dissertations and Theses
An electron microscope with electrostatic lenses was used for high resolution studies of magnetic domains in thin iron films.
Observation methods used to determine the directions of local magnetization in iron thin films were the Lorentz method and the Foucault method.
We studied how Bloch line-crosstie pairs and crosstie main walls behave in applied, in-plane magnetic fields. We found that crosstie main walls remain unchanged until crosstie density goes nearly to zero when the field is applied perpendicular to the main wall. A twisted type of domain appears where crossties disappear.
Portland State Perspective; November 1980, Portland State University
Portland State Perspective; November 1980, Portland State University
Portland State Perspective
A quarterly alumni newsletter. In this issue: PSU Loses Its Biggest Fan; Alumni Notes; 1979-1980 Annual Report; Calendar; In the News.
An Analysis Of Gravity Surveys In The Portland Basin, Oregon, Janice C. Perttu
An Analysis Of Gravity Surveys In The Portland Basin, Oregon, Janice C. Perttu
Dissertations and Theses
The geologic setting of the Portland Basin is ideal for gravity surveys because of the large density contrasts between geologic units. The Portland Basin consists of a north-northwest-trending syncline in the Columbia River basalt overlain by Pliocene to Recent alluvium. This study was undertaken to define structures in the Portland Basin which are obscured by the alluvium.
An areal gravity survey of the Portland Basin covering approximately 450 square kilometers was conducted for this study.
Debye–Hückel Theory For Particles Of Arbitrary Electrical Structure, John D. Ramshaw
Debye–Hückel Theory For Particles Of Arbitrary Electrical Structure, John D. Ramshaw
Physics Faculty Publications and Presentations
Classical linearized Debye–Hückel theory is formulated for a finite fluid system, of arbitrary shape, composed of rigid particles with arbitrary internal electrical structure. The multipole description is eschewed in favor of the more basic description of a particle in terms of its charge density function. This function is left arbitrary, so the particles may be charged or neutral, polar or nonpolar, etc. The theory implies that the direct correlation function c(12)=−v(12)/k T, where v(12) is the Coulomb interaction energy between the charge densities of particles 1 and 2. In the case of uncharged polar …
Pressure Dependence Of Fluorescent And Photolytic Interferences In Ho Detection By Laser-Excited Fluorescence, Thomas M. Hard, Robert J. O'Brien, T. B. Cook
Pressure Dependence Of Fluorescent And Photolytic Interferences In Ho Detection By Laser-Excited Fluorescence, Thomas M. Hard, Robert J. O'Brien, T. B. Cook
Chemistry Faculty Publications and Presentations
In the measurement of HO concentrations by laser-excited fluorescence, expansion of the sampled air offers a way to reduce fluorescent and photolytic interference by other species. The decrease in [HO] upon expansion is balanced by an increase in HO fluorescence yield over a wide range of pressures. Background air fluorescence is reduced if the responsible species have fluorescence yields higher than those of HO. Preliminary experiments indicate that most of the fluorescence observed in laboratory air is due to such species. Upon expansion, the suppression of fluorescent interference can be no greater than the reduction in pressure, whereas the suppression …
Portland State Perspective; July 1980, Portland State University
Portland State Perspective; July 1980, Portland State University
Portland State Perspective
A quarterly alumni newsletter. In this issue: PSU's Earth Sciences Department studies Mount St. Helens; showcasing the work of Frederick Heidel, winner of the 1980 Branford Price Millar Award for Faculty Excellence; and a report on the future impact of technology on the individual.
1980 Commencement Program, Commencement
1980 Commencement Program, Commencement
Commencement Archives 1980-89
The program for the Portland State University 1980 Spring Commencement ceremony, held at Memorial Coliseum on June 8, 1980, in Portland, Oregon.
Opening remarks by Edith Green, Oregon State System of Higher Education, and Reynold Dale Richwine, Class of 1980.
Report On Racial Integration-Desegregation Issues In The Portland Public Schools, City Club Of Portland (Portland, Or.)
Report On Racial Integration-Desegregation Issues In The Portland Public Schools, City Club Of Portland (Portland, Or.)
City Club of Portland
No abstract provided.
Effective Force Constant Ratios: Iron In Iridium And Rhodium, Dennis Munsterman
Effective Force Constant Ratios: Iron In Iridium And Rhodium, Dennis Munsterman
Dissertations and Theses
Classical methods of analyzing heat capacity data for the characteristic moments of the frequency distribution are applied to iridium and rhodium. Impurity moments are determined from high and low temperature f values. These moments are combined by modern theory to estimate the magnitude of the host-host to host-impurity force constant ratio. Ratios of the various host moments are also examined.
Geology Of The Southcentral Margin Of The Tillamook Highlands; Southwest Quarter Of The Enright Quadrangle, Tillamook County, Oregon, Kenneth Allan Cameron
Geology Of The Southcentral Margin Of The Tillamook Highlands; Southwest Quarter Of The Enright Quadrangle, Tillamook County, Oregon, Kenneth Allan Cameron
Dissertations and Theses
The Tillamook Highlands is a largely unmapped volcanic pile located in the north end of the Coast Range of Oregon. The 36 square miles of T. 1 N., R. 8 W., on the southcentral margin of the Highlands, was chosen for detailed study.
The study area is composed of Eocene age sedimentary and volcanic units which were deposited in a filling basin. The lowest units were deposited in moderate to deep marine waters; the uppermost were deposited subaerially.
Polarization Characteristics Of Dye‐Laser Amplifiers I. Unidirectional Molecular Distributions, Lee W. Casperson, Kendall C. Reyzer
Polarization Characteristics Of Dye‐Laser Amplifiers I. Unidirectional Molecular Distributions, Lee W. Casperson, Kendall C. Reyzer
Electrical and Computer Engineering Faculty Publications and Presentations
Many practical laser amplifiers exhibit anisotropic gain due to polarization of the pumping fields or to a fixed preferential alignment of the active dipoles. Several specific causes and consequences of gain anisotropy are discussed in detail. In the analysis, the emphasis is placed on dye‐laser systems including arbitrary amplitudes, phases, and polarizations of the pump and signal fields. Analytical results are presented for a unidrectional molecular distribution, and it is found that the polarization states of the pump and signal fields change with distance in the amplifier.
Portland State Perspective; April 1980, Portland State University
Portland State Perspective; April 1980, Portland State University
Portland State Perspective
A quarterly alumni newsletter. In this issue: students' spirit sparks alumni pledges; and an update on capital construction projects
Partial Chemical Equilibrium In Fluid Dynamics, John D. Ramshaw
Partial Chemical Equilibrium In Fluid Dynamics, John D. Ramshaw
Physics Faculty Publications and Presentations
An analysis is given for the flow of a multicomponent fluid in which an arbitrary number of chemical reactions may occur, some of which are in equilibrium while the others proceed kinetically. The primitive equations describing this situation are inconvenient to use because the progress rates ω [subscript s] for the equilibrium reactions are determined implicitly by the associated equilibrium constraint conditions. Two alternative equivalent equation systems that are more pleasant to deal with are derived. In the first system, the ω [subscript s] are eliminated by replacing the transport equations for the chemical species involved in the equilibrium reactions …
Laser Power Calculations: Sources Of Error, Lee W. Casperson
Laser Power Calculations: Sources Of Error, Lee W. Casperson
Electrical and Computer Engineering Faculty Publications and Presentations
The physical phenomena that dominate the power characteristics of a laser depend on the detailed nature of the amplifying medium and the resonator structure. In predicting the power characteristics, numerous approximations are always required. The most important approximations are considered here in detail, and error estimates are presented so that a designer can select the appropriate model for a particular application. Emphasis is placed on analytic solutions and specific phenomena considered include longitudinal and transverse spatial hole burning, large single-pass gain, and mixed line broadening.
Closed Systems Also Show Equifinality, Martin Zwick
Closed Systems Also Show Equifinality, Martin Zwick
Complex Systems Faculty Publications and Presentations
The purpose of this note is to address a possible source of confusion in the description, which appears often in the systems literature, of "closed" systems, which seems to derive from the early work of von Bertalanffy (1940, 1950, 1968). Specifically, it is commonly stated (e.g., Rapoport, 1968*; Katz and Kahn, 1974; Kast and Rosenzweig, 1976; Kramer and de Smit, 1977) that "open" systems exhibit the property of equifinality, wherein a particular final state of the system may be reached via different routes from different initial states, in contrast to "closed" systems, where different initial states always result in correspondingly …
The Structure And Stratigraphy Of The Columbia River Basalt In The Chehalem Mountains, Oregon, Abdul-Rahman Mohammed Al-Eisa
The Structure And Stratigraphy Of The Columbia River Basalt In The Chehalem Mountains, Oregon, Abdul-Rahman Mohammed Al-Eisa
Dissertations and Theses
The Chehalem Mountains area, encompassing 70 square kilometers, is at the western extent of the Columbia River Basalt Group as mapped in western Oregon. The flows in the study area were identified as belonging to subdivisions of the Columbia River Basalt Group on the basis of physical characteristics and trace element geochemistry. The basalt flows are poorly exposed in the area and weathering is deep and extensive where the flows have been exposed. Where erosion has exposed the underlying marine sedimentary rocks, the basalt has failed in landslides.
Stratigraphy And Sedimentation Of The Spencer Formation In Yamhill And Washington Counties, Oregon, Fathi Ayoub Al-Azzaby
Stratigraphy And Sedimentation Of The Spencer Formation In Yamhill And Washington Counties, Oregon, Fathi Ayoub Al-Azzaby
Dissertations and Theses
The Spencer Formation in Yamhill and Washington Counties, Oregon, is exposed in a narrow belt 27 km long, from 1/4 to 3 km wide and with a maximum thickness of about 400 m. The formation is composed entirely of sandstone with interbedded thin layers of mudstone in the uppermost member. The sedimentary structure and paleoecology indicate a shallow marine depositional environment. The upper member of the Spencer Formation contains more quartz, plagioclase, and hornblende than does the lower member, but K-feldspar is less than that of the lower member. Shallower water conditions for the deposition of the upper member are …
Community Impacts On Organizational Interaction, Frederick Dalton Keast
Community Impacts On Organizational Interaction, Frederick Dalton Keast
Dissertations and Theses
This dissertation addresses the following research question. Do the criteria by which organizations assess the benefits of entering into interagency agreements vary by city? Employing data obtained from 183 human service agencies in six western cities, organizational emphases on two classes of goals as they relate to the decision to interact with other agencies are assessed as functions of six organizational variables and city. The organizational variables include organizational goal, reliance on federal sources for funding, and a range of environmental uncertainty measures. The two classes of organizational goals studied are: first, those which directly accrue to the agency itself, …
Surface Area Of Coal As Influenced By Low Temperature Oxidation Processes, Salvador Leon Arredondo
Surface Area Of Coal As Influenced By Low Temperature Oxidation Processes, Salvador Leon Arredondo
Dissertations and Theses
The possibility of increasing the amount of readily accessible surface area by enlarging the 5 A pore was examined via pretreating the PSOC-371 coal with gases such as nitrogen, nitrogen-oxygen, and ozone-oxygen and hydrogen peroxide solutions. Surface areas were obtained from nitrogen adsorption at 77 K and carbon dioxide adsorption at either 298 or 195 K for each sample before and after treatment.
Transport Of Ozone Across An Air/Water Interface Coupled With Aqueous Decomposition, Ahmad Ali Mehrabzadeh
Transport Of Ozone Across An Air/Water Interface Coupled With Aqueous Decomposition, Ahmad Ali Mehrabzadeh
Dissertations and Theses
Photoacoustic spectroscopy was used to analyze the transport of ozone through the air/water interface. Experimental results showed that the ozone transport rate is similar to rates measured for other gases of low solubility and low reactivity. The transport rate increases with increasing pH. The decomposition rate of ozone was studied in solutions. The decomposition rate also depends on the pH of the solution, and in high pHs both the deposition velocity and the decomposition rate constant of ozone have larger values. The value of the deposition velocity (Kd) is 3.7 ± .9 x 10-3 cm/sec and the decomposition rate …
Stability And Resilience In Business Systems, Donald Bard Wilcox
Stability And Resilience In Business Systems, Donald Bard Wilcox
Dissertations and Theses
The purposes of this research report are (1) to introduce into financial management theory, the concepts of stability, resilience and steady state from general systems theory, (2) to formulate hypotheses about the relationships among rate of return, business risk, stability and resilience as exhibited by business systems, (3) to construct quantifiable surrogates for these concepts in terms of the financial operating characteristics of business systems and (4) to test the hypotheses with an appropriate statistical methodology. Business systems are investigated from two different perspectives or levels of aggregation. The first level treats each individual firm as the business system. The …
Geology Of The Columbia River Basalt In Silver Falls State Park, Oregon, Elizabeth Storm Norman
Geology Of The Columbia River Basalt In Silver Falls State Park, Oregon, Elizabeth Storm Norman
University Honors Theses
Silver Falls State Park is near the southern extent of the Columbia River Basalt Group as mapped in western Oregon. The flows in the park were identified as belonging to subdivisions of the Columbia River Basalt Group on the basis of physical characteristics and trace element geochemistry. The sequence of flows present is as follows: 3-4 flows of the Low-Mg chemical type of the Grande Ronde Basalt, 2 flows of the High-Mg chemical type of the Grande Ronde Basalt, 3 flows of the Frenchman Springs Member of the Wanapum Basalt, and one flow of anomolous geochemistry. The flows dip west …