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Morris, D. W.

Publications and source records attributed to Morris, D. W..

Network simulation using the simulation language for alternate modeling (SLAM 2)

The simulation language for alternate modeling (SLAM 2) is a general purpose language that combines network, discrete event, and continuous modeling capabilities in a single language system. The efficacy of the system's network modeling is examined and discussed. Examples are given of the symbolism that is used, and an example problem and model are derived. The results are discussed in terms of the ease of programming, special features, and system limitations. The system offers many features which allow rapid model development and provides an informative standardized output. The system also has limitations which may cause undetected errors and misleading reports unless the user is aware of these programming characteristics.

Shen, S.

Orbiter ECLSS support of Shuttle payloads

The orbiter ECLSS (Environmental Control and Life Support System) provides the functions of atmosphere revitalization, crew life support, and active thermal control. This paper describes these functions as they relate to the support of Shuttle payloads, including automated spacecraft, Spacelab and Department of Defense missions. Functional and performance requirements for the orbiter ECLSS which affect payload support are presented for the atmosphere revitalization subsystem, the food, water and waste subsystem, and the active thermal control subsystem. Schematics for these subsystems are also described. Finally, based on the selected orbiter configuration, preliminary design and off-design thermodynamic data are presented to quantify the baseline orbiter capability; to quantify the payload chargeable penalties for increasing this support; and to identify the significant limits of orbiter ECLSS support available to Shuttle payloads.

Jaax, J. R.

Modular radiator system development for shuttle and advanced spacecraft.

Previous spacecraft heat rejection systems have been tailored to a specific spacecraft and a specific mission. Many different panel designs, fluids, and control methods have been used with no significant degree of commonality. For future spacecraft, it is desirable to have heat rejection systems which can accommodate widely varying loads and have a high degree of commonality to minimize development requirements. A modular radiator system which satisfies this requirement and is adaptable to a variety of future vehicles and missions is described. A test program with two modular panels connected in several flow arrangements, which are representative of candidate shuttle orbiter and other future spacecraft applications, is described.

Dietz, J. B.