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Ross, C.

Publications and source records attributed to Ross, C..

Traces of Fallback Breccia on the Rim of Barringer Meteorite Crater (a.k.a. Meteor Crater), Arizona

Barringer Meteorite Crater (a.k.a. Meteor Crater), Arizona, is one of the youngest and best preserved impact craters on Earth. For that rea-son, it provides a baseline for similar craters formed in the geologic past, formed elsewhere in the Solar Sys-tem, and illuminates the astronomical and geological processes that produce them. The crater has not, how-ever, escaped erosion completely. While Shoemaker [1] mapped a breccia with fallback components inside the crater, he did not locate it beyond the crater rim. He only found remnants of that type of debris in re-worked alluvium [1; see also 2]. Fallback breccia and any base-surge deposits have, thus, been missing components in studies of material ejected beyond the transient crater rim.

Erickson, Timmons M.

RHrFPGA Radiation-Hardened Re-programmable Field-Programmable Gate Array

Viewgraphs on the development of the Radiation-Hardened Re-programmable Field-Programmable Gate Array (RHrFPGA) are presented. The topics include: 1) Radiation Test Suite; 2) Testing Interface; 3) Test Configuration; 4) Facilities; 5) Test Programs; 6) Test Procedure; and 7) Test Results. A summary of heavy ion and proton testing is also included.

Sanders, A. B.

Structural optimization with constraints from dynamics in Lagrange

Structural optimization problems are mostly solved under constraints from statics, such as stresses, strains, or displacements under static loads. But in the design process, dynamic quantities like eigenfrequencies or accelerations under dynamic loads become more and more important. Therefore, it is obvious that constraints from dynamics must be considered in structural optimization packages. This paper addresses the dynamics branch in MBB-LAGRANGE. It will concentrate on two topics, namely on the different formulations for eigenfrequency constraints and on frequency response constraints. For the latter the necessity of a system reduction is emphasized. The methods implemented in LAGRANGE are presented and examples are given.

Pfeiffer, F.

HAL/SM system functional design specification

The functional design of a preprocessor, and subsystems is described. A structure chart and a data flow diagram are included for each subsystem. Also a group of intermodule interface definitions (one definition per module) is included immediately following the structure chart and data flow for a particular subsystem. Each of these intermodule interface definitions consists of the identification of the module, the function the module is to perform, the identification and definition of parameter interfaces to the module, and any design notes associated with the module. Also described are compilers and computer libraries.

Ross, C.

HAL/SM language specification

A programming language is presented for the flight software of the NASA Space Shuttle program. It is intended to satisfy virtually all of the flight software requirements of the space shuttle. To achieve this, it incorporates a wide range of features, including applications-oriented data types and organizations, real time control mechanisms, and constructs for systems programming tasks. It is a higher order language designed to allow programmers, analysts, and engineers to communicate with the computer in a form approximating natural mathematical expression. Parts of the English language are combined with standard notation to provide a tool that readily encourages programming without demanding computer hardware expertise. Block diagrams and flow charts are included. The semantics of the language is discussed.

Williams, G. P. W., Jr.