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Kozma, A.

Publications and source records attributed to Kozma, A..

Modeling of SAR signatures of shallow water ocean topography

A hydrodynamic/electromagnetic model was developed to explain and quantify the relationship between the SEASAT synthetic aperture radar (SAR) observed signatures and the bottom topography of the ocean in the English Channel region of the North Sea. The model uses environmental data and radar system parameters as inputs and predicts SAR-observed backscatter changes over topographic changes in the ocean floor. The model results compare favorably with the actual SEASAT SAR observed backscatter values. The developed model is valid for only relatively shallow water areas (i.e., less than 50 meters in depth) and suggests that for bottom features to be visible on SAR imagery, a moderate to high velocity current and a moderate wind must be present.

Shuchman, R. A.

Optimal read/write memory system components

Two holographic data storage and display systems, voltage gradient ionization system, and linear strain manipulation system are discussed in terms of creating fast, high bit density, storage device. Components described include: novel mounting fixture for photoplastic arrays; corona discharge device; and block data composer.

Kozma, A.

Optical read/write memory system components

The optical components of a breadboard holographic read/write memory system have been fabricated and the parameters specified of the major system components: (1) a laser system; (2) an x-y beam deflector; (3) a block data composer; (4) the read/write memory material; (5) an output detector array; and (6) the electronics to drive, synchronize, and control all system components. The objectives of the investigation were divided into three concurrent phases: (1) to supply and fabricate the major components according to the previously established specifications; (2) to prepare computer programs to simulate the entire holographic memory system so that a designer can balance the requirements on the various components; and (3) to conduct a development program to optimize the combined recording and reconstruction process of the high density holographic memory system.

Kozma, A.