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Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
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Showing 1 to 20 of 52 for “"surface currents"”.
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Evolution of diurnal surface winds and surface currents for Monterey Bay
The diurnal-period fluctuations of winds and surface currents are analyzed for September 1992 in and around Monterey Bay. Wind records are compared for three coastal stations and two mooring sites. Remotely-sensed surface current observations from two CODAR (HF radar) sites are used to explore the …
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Fluctuating surface currents : a new algorithm for efficient prediction of Casimir interactions among arbitrary materials in arbitrary geometries
… Our new technique, which we term the fluctuating-surface-current (FSC) approach to computational Casimir physics, borrows ideas from the boundary-element method of computational electromagnetism to express Casimir energies, forces, and torques between bodies of arbitrary shapes and materials in …
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UNDERSTANDING THE PHYSICAL OCEANOGRAPHY OF THE MISSISSIPPI SOUND: OBSERVATIONAL CLIMATOLOGIES, TRENDS AND RELATIONSHIPS IN THE SOUND AND COMPARISON OF THE SURFACE CURRENTS OF OCEAN MODELS WITH HIGH FREQUENCY RADAR DATA
… been obtained. Additionally, comparison of the surface current components measured from High Frequency Radar and simulated by ocean models has been accomplished to better understand the surface circulation of the Sound, guide through the improvement of the models and get insights about the …
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Retrieval of equivalent currents by the use of an integral representation and the extinction theorem --- radome applications
… radome is diagnosed by recreating the equivalent surface currents on its surface from measured near fields. It is shown how the radome interacts with the field, creating beam deflection, pattern distortion, etc. The phase shift of the field due to the transmission through the radome, i.e., the …
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Structure and Persistence of Surface Ship Wakes
… This includes turbulent hydrodynamics, free-surface effects, environmental forcing through Langmuir-type circulations, generation of surface currents and redistribution of surface-active substances, surface-roughness modification, and simulation of the signature generated by reflection and …
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Study on transformation-based invisibility cloaks
… cloak will induce electric and magnetic surface currents along the 0 direction at the inner boundary of this cloak. These surface currents have no counterparts in the transformation theory because they do not exist before transformation. Secondly, the reciprocity of a spherical cloak is …
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Towards Improved Estimates of Upper Ocean Energetics
… according to the interaction between ocean surface currents and surface wind stress, a number of surface current decompositions can be used to decompose wind work calculations. In this research, geostrophic, ageostrophic, Ekman, and total current decompositions are all used to calculate wind …
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Multiple feed reflector antenna analysis
… to form the total field used in finding the surface currents of the physical optics radiation integral. The technique allows each element to be arbitrarily excited, positioned and oriented. The element patterns may be different allowing mutual coupling to be included.
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Synthesis process using characteristic modes for multiple in situ antennas for system radiation requirements
… order modes on structures. It compares the surface currents for each mode and determines a feed region. The element is then designed based on the feed location and the required direction of the surface current. When the desired pattern is not associated with a modal far field, this …
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Switched aperture surface current measurements
The measurement of induced surface currents on antennas, scatterers, and other structures is important for a variety of reasons, including in-situ measurements and validation of simulated results. Techniques for measuring the complete vector nature of surface currents (magnitude, direction, and …
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Agulhas current variability determined from space : a multi-sensor approach
… more than 6 years of high frequency Sea Surface Temperature (SST) imagery as well as surface current observations derived from 18 years of merged-altimetry and over 2 years of Advanced Synthetic Aperture Radar (ASAR) observations are combined to study the variability of the Agulhas …
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Theory and applications of chirality in microstrip antennas
… aim of this study is to analyze radiation from surface currents lying on an interface between a grounded, planar, lossless, isotropic, chiral slab and a simple lossless dielectric half-space. An eigenvalue-eigenfunction approach, specifically the Ohm-Raleigh method, is employed to obtain a modal …
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Method of Moments Analysis of an Aperture in a Thick Ground Plane
… is almost impossible to determine. Therefore the surface equivalence principle is used to reduce this complex problem into three simpler ones. Each such problem consists of equivalent surface currents radiating in unbounded media. Therefore the free space Green's function is used for each problem. …
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Surface-referenced current meter measurements
… of possible techniques for observation of near-surface currents indicates that the surface-following frame of reference will provide several advantages over the Eulerian or Lagrangian frames. One problem with surface-following measurements is the biasing effects of the waves. A technique for …
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Understanding the physical, chemical and biological processes across the subtropical convergence during austral automn
… were strongly correlated, as expected. The surface currents showed cyclonic motion between 38° - 39°E and 38 - 42°S, with the exception of an eddy-like feature between 39.5°and 40.5"S and generally anti-cyclonic motion to the east of 39°E.
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Directional wavenumber characteristics of short sea waves
Interest in short waves on the ocean surface has been growing over the last three decades because they play an important role in surface electromagnetic (e.m.) scattering. Currently radars and scatterometers which use e.m. scattering to remotely examine the ocean can produce estimates of the …
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Method of Moment Analysis of Partially Shielded Chiral Bodies of Revolution
… are computed. The problem is solved using the surface equivalence principle. The scattered fields outside the structure are assumed to be produced by an equivalent magnetic surface current that exists on the unshielded part of the BOR surface and an external equivalent electric surface current …
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Single and multiple electromagnetic scattering by dielectric obstacles from a resonance perspective
… the SEM is generally considered a theory for surface currents on conducting scatterers, extensions are made which permit, under certain conditions, a singularity expansion representation of the electromagnetic field scattered by a dielectric scatterer. Application of this expansion is then …
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Improvements to a Real-Time, Satellite-Derived Surface Current Product (OSCAR) and Evaluation in the Intra-American Sea
… linear predictive coding for use in the Ocean Surface Currents Analysis, Real-time (OSCAR) is developed and tested. This method is implemented by Earth and Space Research (ESR) to produce operational height fields that are in turn used to calculate the geostrophic component velocity of OSCAR. …
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Physical Controls on Low and Mid-Latitude Marine Primary Productivity
… by changes in the westward transport, via surface currents, of relatively cold, nutrient-rich waters that have been upwelled in the eastern Equatorial Pacific. The importance of horizontal nutrient supply is further evidenced by an analysis of seasonal variability in the subtropical North …
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