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Elliot, L.

Publications and source records attributed to Elliot, L..

A data management system for engineering and scientific computing

Data elements and relationship definition capabilities for this data management system are explicitly tailored to the needs of engineering and scientific computing. System design was based upon studies of data management problems currently being handled through explicit programming. The system-defined data element types include real scalar numbers, vectors, arrays and special classes of arrays such as sparse arrays and triangular arrays. The data model is hierarchical (tree structured). Multiple views of data are provided at two levels. Subschemas provide multiple structural views of the total data base and multiple mappings for individual record types are supported through the use of a REDEFINES capability. The data definition language and the data manipulation language are designed as extensions to FORTRAN. Examples of the coding of real problems taken from existing practice in the data definition language and the data manipulation language are given.

Elliot, L.

Six-color photometry of Iapetus, Titan, Rhea, Dione and Tethys

The extensive photometric observations of Titan, Iapetus, Rhea, Dione and Tethys have made it possible to separate the solar phase and orbital phase contributions to the observed light variations of these satellites. For Titan, the wavelength dependence of its solar phase coefficient has been obtained. This dependence should prove useful in constructing future model atmospheres. The other four satellites show a surprising array of different photometric behaviors. Despite these differences, all four satellites have similar spectral reflectivities. Clearly Iapetus, Rhea, Dione and Tethys are complex objects, varying substantially from one another in surface structure and/or composition.

Noland, M.