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Engineering topics

Wagner, P. E.

Publications and source records attributed to Wagner, P. E..

Performance of candidate SEPS solar cells as a function of low temperature and low intensity exposure and 1 MeV electron irradiation

The behavior of 144 high-performance shallow-junction silicon solar cells under conditions of low temperature and intensity was examined. The cells represented nine combinations of thickness, base resistivity, front surface texture, and rear surface treatment. At least 16 cells of each type were individually tested both as active elements under light levels between 0.04 and 1.0 solar constant and in the dark as passive rectifiers under external forward bias. One cell type was also irradiated with 1 MeV electrons up to 2.7 x 10 to the 15th e/sq cm. The inferior cells demonstrated high ohmic and/or non-ohmic shunting. No series resistance or Schottky barrier effects were observed. Fluences beyond 10 to the 13th e/sq cm lowered cell current, probably by increasing volume recombination.

Whitaker, A. F.↗

On measuring the state of the bay

The requirements necessary to establish a comprehensive data base for the Chesapeake Bay are discussed. Three essential questions were addressed: (1) which entities should be measured; (2) how close together should measurements be made in space and time; and (3) what should be done with the data. Possible answers to the questions were evaluated in relation to existing technology, cost effectiveness, and potential uses of the data base.

Wagner, P. E.↗

Role of remote sensing in documenting living resources

Specific cases of known or potentially useful applications of remote sensing in assessing biological resources are discussed. It is concluded that the more usable remote sensing techniques relate to the measurement of population fluctuations in aquatic systems. Sensing of the flora and the fauna of the Bay is considered with emphasis on direct sensing of aquatic plant populations and of water quality. Recommendations for remote sensing projects are given.

Wagner, P. E.↗