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Filtering by: Creator Alexander, J. Andrew Remove constraint Creator: Alexander, J. Andrew Degree Level Doctoral Remove constraint Degree Level: Doctoral

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  • A taxonomic revision of Astragalus mokiacensis and allied taxa within the Astragalus lentiginosus complex of Section Diphysi

    Creator:
    Alexander, J. Andrew
    Abstract:
    North America, with over 400 species of Astragalus (Fabaceae), is one of three major centers of diversity, all of which comprise the majority of the nearly 1750 species of Astragalus worldwide. One of the most diverse species, Astragalus lentiginosus of Section Diphysi, is a polymorphic complex of over 40 varieties,...
    Resource Type:
    Dissertation
    Full Text:
    THESIS OF J. Andrew Alexander for the degree of Doctor of Philosophy in Botany and Plant Pathology

  • Interactions of wind-driven and tidally-driven circulation in the Oregon coastal ocean

    Creator:
    Osborne, John J.
    Abstract:
    Influences of tidal and slower (subtidal) oceanic flows over the continental shelf and slope off Oregon are studied using a high-resolution ocean circulation model and comparative model-data analyses. The model is based on the Regional Ocean Modeling System (ROMS), a fully nonlinear, three-dimensional model (using hydrostatic and Boussinesq approximations). The...
    Resource Type:
    Dissertation
    Full Text:
    AN ABSTRACT OF THE DISSERTATION OF John J. Osborne V

  • Hybrid computer simulation of wind-driven ocean currents

    Creator:
    Vithayathil, Francis Joseph
    Abstract:
    A simulation method using a hybrid computer is developed in this dissertation to enhance the study of wind-driven ocean circulation. The simulation is based on the mathematical model developed by Ekman. Pure digital simulation is not economical due to excessive computer time required for the solution of the partial differential...
    Resource Type:
    Dissertation
    Full Text:
    OCEAN CURRENTS Abstract approved: Redacted for privacy Associate Professor Gerald/C. Alexander A

  • Out-migration, income and poverty in nonmetropolitan America

    Creator:
    Marre, Alexander
    Abstract:
    Why do rural households leave for urban places? And how does this decision affect their economic well-being? Rural places in the United States have higher poverty and unemployment rates and lower levels of educational attainment relative to urban places. Does leaving a rural place for a city offer a pathway...
    Resource Type:
    Dissertation
    Full Text:
    Alexander William Marré for the degree of Doctor of Philosophy in Agricultural and Resource Economics

  • Ensemble-variational data assimilation for dynamically challenging coastal ocean circulation

    Creator:
    Pasmans, Ivo
    Abstract:
    Currently, forecasts produced by the Oregon-Washington (OR-WA) Coastal Ocean Forecast System are constrained by assimilation of only surface observations. The 4-dimensional variational (4DVAR) data assimilation (DA) algorithm is utilized to combine the model and the data, with the time-independent forecast ("background'') error covariance B. In this study, two possible improvements...
    Resource Type:
    Dissertation
    Full Text:
    Circulation Abstract approved: Alexander L. Kurapov Currently, forecasts produced by the Oregon-Washington

  • Analysis of the D. C. electric field for a pipeline in a three layered earth

    Creator:
    Brandenstein, Albert Edward
    Abstract:
    This paper develops an equation, from an heuristic set of assumptions, which describes the axial current, leakage current, resultant electric field, and resultant earth potential occurring when a pipeline buried within a resistive earth is subjected to a distributed, primary, axial, electrostatic field produced from a high-voltage, direct-current (HVDC) power...
    Resource Type:
    Dissertation
    Full Text:
    approved: G. C. Alexander This paper develops an equation, from an heuristic set of as- sumptions, which

  • Capacitive coupling compensation facilitating single-pole switching on six-phase transmission lines

    Creator:
    Al-Shehri, Abdallah M.
    Abstract:
    In this research, a novel shunt compensation scheme design procedure is developed for unbalanced, untransposed n-phase transmission lines. The main function of the scheme is to reduce the effect of the capacitive coupling on untransposed transmission lines to levels where successful single-pole switching is assured. The analysis procedure is carried...
    Resource Type:
    Dissertation
    Full Text:
    privacy Abstract approved: Gerald C. Alexander In this research, a novel shunt compensation scheme

  • A signal-processed antenna system and the simulation of the effects of balanced-mixer frequency conversion

    Creator:
    Spencer, Kenneth Edward
    Abstract:
    In this paper a signal-processed antenna and receiver system is proposed and analyzed. In addition, a simulation of the balanced-mixer portion of the processing system is made on a hybrid computer to find the bandwidth limitations for the total system. The system utilizes both the amplitude and phase information of...
    Resource Type:
    Dissertation
    Full Text:
    OF BALANCED -MIXER FREQUENCY CONVERSION Abstract approved: Gerald C. Alexander In this paper a

  • Frequency-domain, parameter estimation for a brushless, doubly-fed machine

    Creator:
    Ramchandran, Ashok
    Abstract:
    A Brushless, Doubly Fed Machine (BDFM) attempts to combine the advantages of conventional induction and synchronous types of electrical machines by its unique architecture. The validation of BDFM designs in an actual test environment requires the estimation of the BDFM model parameters from actual experimentation. Accurate values for the parameters...
    Resource Type:
    Dissertation
    Full Text:
    , Parameter Estimation for a Brush less, Doubly-Fed Machine Abstract apt:a: Ned: Gerald C. Alexander A

  • Identification of synchronous machine parameters

    Creator:
    Shaban, Ali Omar
    Abstract:
    The synchronous machine is an essential component of a power system and determination of its parameters accurately is an important task in securing adequate modes of operation through certain control strategies. An estimation technique based on the Powell algorithm was evaluated for the identification of these parameters on the basis...
    Resource Type:
    Dissertation
    Full Text:
    Abstract approved: Redacted for Privacy Gerald Corwin Alexander The synchronous machine is an essential