Comment on 'The O2 atmospheric dayglow in the thermosphere' by M. R. Torr, B. Y. Welsh, and D. G. Torr
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Slanger, T. G.↗
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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.
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The MOLICEL(R) rechargeable lithium system: Multicell battery aspects
MOLICEL rechargeable lithium cells were cycled in batteries using series, parallel, and series/parallel connections. The individual cell voltages and branch currents were measured to understand the cell interactions. The observations were interpreted in terms of the inherent characteristics of the Li/MoS2 system and in terms of a singular cell failure mode. The results confirm that correctly configured multicell batteries using MOLICELs have performance characteristics comparable to those of single cells.
Fouchard, D.↗
Recent Sikorsky R and D progress
The recent activities and progress in four specific areas of Sikorsky's research and development program are summarized. Since the beginning of the S-76 design in 1974, Sikorsky has been aggressively developing the technology for using composite materials in helicopter design. Four specific topics are covered: advanced cockpit/controller efforts, fly-by-wire controls on RSRA/X-Wing, vibration control via higher harmonic control, and main rotor aerodynamic improvements.
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Sixteenth NASTRAN (R) Users' Colloquium
These are the proceedings of the Sixteenth NASTRAN Users' Colloquium held in Arlington, Virginia from 25 to 29 April, 1988. Technical papers contributed by participants review general application of finite element methodology and the specific application of the NASA Structural Analysis System (NASTRAN) to a variety of static and dynamic structural problems.
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Comments on 'Saugus-Palmdale, California, field test for refraction error in historical leveling surveys' by Ross S. Stein, Charles T. Whalen, Sanford R. Holdahl, William E. Strange, and Wayne Thatcher
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Reilinger, Robert↗
NASA's Telerobotics R & D Program - Status and future directions
NASA's telerobotics technology program is described as well as the process for the transfer of this technology to the Space Station, and some of the implications of the technology for station design and operations, including those for international cooperation. A diagram is presented of the NASREM control heirarchy with the Office of Aeronautics and Space Technology telerobot testbed architecture superimposed. In telerobotics, the following areas were identified as possible subjects for developing data to support international standards: (1) task boards, (2) system performance measures on task boards, (3) human performance measures on task boards with teleoperation, and (4) autonomous-telerobotic-teleoperated performance comparisons.
Pivirotto, Donna Shirley↗
NASA Earth-to-orbit propulsion R and T
Information is given in viewgraph form on Earth-to-orbit propulsion research and technology, space transportation systems, spacecraft configurations, booster technology and hybrid propellant rocket engines.
Richmond, Robert J.↗
HOST combustion R and T overview
The overall objective of the Turbine Engine Hot Section Technology Combustion Project was to develop and verify improved and more accurate numerical analysis methods for increasing the ability to design with confidence combustion systems for advanced aircraft gas turbine engines. The objective was approached from two directions: computational and experimental. On the computational side, the approach was to first assess and evaluate existing combustor aerothermal analysis models. On the experimental side, three types of experiments are identified; first, fundamental experiments directed toward improved understanding of the flow physics and chemistry; second, experiments run to provide data for the empirical modeling of complex phenomena; and third, benchmark experiments for computer code validation.
Gaugler, Raymond E.↗
HOST surface protection R and T overview
Most of the efforts in the HOST Surface Protection Subproject were focused on thermal barrier coating (TBC) life prediction. Also, a small effort, consisting primarily of wrapping up and reporting the work of previous years, remained on the airfoil deposition modeling. The work performed under the airfoil deposition modeling program element was concerned with modeling the deposition of corrodants onto turbine airfoils. Accomplishments included verification of the chemically frozen boundary (CFBL) theory. Encouraging results were also achieved with the recently developed local thermochemical equilibrium (LTCE) theory. The surface protection subprogram was devoted to thermal-barrier-coating life modeling. This modeling is an essential step in the development of TBC's.
Miller, Robert A.↗
First International Conference on Ada (R) Programming Language Applications for the NASA Space Station, volume 1
Topics discussed include: test and verification; environment issues; distributed Ada issues; life cycle issues; Ada in Europe; management/training issues; common Ada interface set; and run time issues.
Bown, Rodney L.↗
Ada(R) Test and Verification System (ATVS)
The Ada Test and Verification System (ATVS) functional description and high level design are completed and summarized. The ATVS will provide a comprehensive set of test and verification capabilities specifically addressing the features of the Ada language, support for embedded system development, distributed environments, and advanced user interface capabilities. Its design emphasis was on effective software development environment integration and flexibility to ensure its long-term use in the Ada software development community.
Strelich, Tom↗
Using Ada (R) on a workstation for large projects
Alsys has implemented validated Ada compilers that are hosted and targeted on a variety of microprocessor-based workstations, including the IBM PC/AT. The availability of Ada compilers for these kinds of inexpensive, widely available machines considerably enhances the development options for large efforts such as the NASA Space Station, and this is addressed from both an implementation and a user perspective. First, the issue of large program development on a workstation is discussed: how the compiler must handle this, and how an inherently decentralized approach can be managed. Next, the focus is on code efficiency and the compiler and run-time design decisions that help meet this goal are described. It is concluded with a presentation of benchmarks that are quite encouraging with respect to the run-time efficiency of Ada code compared with other languages.
Avakian, Arra S.↗
Ada (R) assessment: An important issue within European Columbus Support Technology Programme
Software will be more important and more critical for Columbus than for any ESA previous project. As a simple comparison, overall software size has been in the range of 100 K source statements for EXOSAT, 500 K for Spacelab, and will probably reach several million lines of code for Columbus (all element together). Based on past experience, the total development cost of software can account for about 10 pct to 15 pct of the total space project development cost. The Ada technology may support the strong software engineering principles needed for Columbus, provided that technology is sufficiently mature and industry plans are meeting the Columbus project schedule. Over the past 3 years, Informatique Internationale has conducted a coherent program based on Ada technology assessment studies and experiments, for ESA and CNES. This specific research and development program benefits from 15 years experience in the field of space software development and is supported by the overall software engineering expertise of the company. The assessment and experiments of Ada software engineering by Informatique Internationale are detailed.
Vielcanet, P.↗
First International Conference on Ada (R) Programming Language Applications for the NASA Space Station, volume 2
Topics discussed include: reusability; mission critical issues; run time; expert systems; language issues; life cycle issues; software tools; and computers for Ada.
Bown, Rodney L.↗
Lessons learned in creating spacecraft computer systems: Implications for using Ada (R) for the space station
Twenty-five years of spacecraft onboard computer development have resulted in a better understanding of the requirements for effective, efficient, and fault tolerant flight computer systems. Lessons from eight flight programs (Gemini, Apollo, Skylab, Shuttle, Mariner, Voyager, and Galileo) and three reserach programs (digital fly-by-wire, STAR, and the Unified Data System) are useful in projecting the computer hardware configuration of the Space Station and the ways in which the Ada programming language will enhance the development of the necessary software. The evolution of hardware technology, fault protection methods, and software architectures used in space flight in order to provide insight into the pending development of such items for the Space Station are reviewed.
Tomayko, James E.↗
The computerization of programming: Ada (R) lessons learned
One of the largest systems yet written in Ada has been constructed. This system is the Intermetrics Ada compiler. Many lessons have been learned during the implementation of this Ada compiler. Some of these lessons, concentrating on those lessons relevant to large system implementations are described. The characteristics of the Ada compiler implementation project at Intermetrics are also described. Some specific experiences during the implementation are pointed out.
Struble, Dennis D.↗
Seventeenth NASTRAN (R) Users' Colloquium
General application of finite element methodology and the specific application of the NASA Structural Analysis System, NASTRAN, to a variety of static and dynamic structural problems were reviewed.
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Improved performance in NASTRAN (R)
Three areas of improvement in COSMIC/NASTRAN, 1989 release, were incorporated recently that make the analysis program run faster on large problems. Actual log files and actual timings on a few test samples that were run on IBM, CDC, VAX, and CRAY computers were compiled. The speed improvement is proportional to the problem size and number of continuation cards. Vectorizing certain operations in BANDIT, makes BANDIT run twice as fast in some large problems using structural elements with many node points. BANDIT is a built-in NASTRAN processor that optimizes the structural matrix bandwidth. The VAX matrix packing routine BLDPK was modified so that it is now packing a column of a matrix 3 to 9 times faster. The denser and bigger the matrix, the greater is the speed improvement. This improvement makes a host of routines and modules that involve matrix operation run significantly faster, and saves disc space for dense matrices. A UNIX version, converted from 1988 COSMIC/NASTRAN, was tested successfully on a Silicon Graphics computer using the UNIX V Operating System, with Berkeley 4.3 Extensions. The Utility Modules INPUTT5 and OUTPUT5 were expanded to handle table data, as well as matrices. Both INPUTT5 and OUTPUT5 are general input/output modules that read and write FORTRAN files with or without format. More user informative messages are echoed from PARAMR, PARAMD, and SCALAR modules to ensure proper data values and data types being handled. Two new Utility Modules, GINOFILE and DATABASE, were written for the 1989 release. Seven rigid elements are added to COSMIC/NASTRAN. They are: CRROD, CRBAR, CRTRPLT, CRBE1, CRBE2, CRBE3, and CRSPLINE.
Chan, Gordon C.↗