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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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NASA NTRS1992

Running SINDA '85/FLUINT interactive on the VAX

Computer software as engineering tools are typically run in three modes: Batch, Demand, and Interactive. The first two are the most popular in the SINDA world. The third one is not so popular, due probably to the users inaccessibility to the command procedure files for running SINDA '85, or lack of familiarity with the SINDA '85 execution processes (pre-processor, processor, compilation, linking, execution and all of the file assignment, creation, deletions and de-assignments). Interactive is the mode that makes thermal analysis with SINDA '85 a real-time design tool. This paper explains a command procedure sufficient (the minimum modifications required in an existing demand command procedure) to run SINDA '85 on the VAX in an interactive mode. To exercise the procedure a sample problem is presented exemplifying the mode, plus additional programming capabilities available in SINDA '85. Following the same guidelines the process can be extended to other SINDA '85 residence computer platforms.

Simmonds, Boris↗

NASA NTRS1993

Arctic sea ice albedo - A comparison of two satellite-derived data sets

Spatial patterns of mean monthly surface albedo for May, June, and July, derived from DMSP Operational Line Scan (OLS) satellite imagery are compared with surface albedos derived from the International Satellite Cloud Climatology Program (ISCCP) monthly data set. Spatial patterns obtained by the two techniques are in general agreement, especially for June and July. Nevertheless, systematic differences in albedo of 0.05 - 0.10 are noted which are most likely related to uncertainties in the simple parameterizations used in the DMSP analyses, problems in the ISCCP cloud-clearing algorithm and other modeling simplifications. However, with respect to the eventual goal of developing a reliable automated retrieval algorithm for compiling a long-term albedo data base, these initial comparisons are very encouraging.

Schweiger, Axel J.↗

NASA NTRS1997

34th JANNAF Combustion Subcommittee Meeting: MURI Technology - Volume 2

This volume is a compilation of 48 unclassified/unlimited distribution papers presented at the 1997 meeting of the JANNAF 34th Combustion Subcommittee (CS) held jointly with the Propulsion Systems Hazards Subcommittee (PSHS), and the Airbreathing Propulsion Subcommittee. Proceedings of the CS, PSHS and APS meetings are published separately by CPIA. The CS Meeting Proceedings are published in four volumes. The JANNAF papers contained in this volume contributed to the Second Year Progress Review of the Multidisciplinary University Research Initiative Program (MURI) on 'Novel New Ingredients to Stabilize Rocket Motors'. Technical progress made on this program was presented as JANNAF CS papers contained in Volumes 2 and 4. Papers contained in this volume review bi-plateau propellant combustion, AP and metal combustion, solid propellant combustion instability fundamentals and motor applications, gas-phase and condensed-phase kinetics, and measurement techniques.

Fry, Ronald S.↗

NASA NTRS1992

Survey Parameters and Availability of Low-level Aeromagnetic Data for Geomagnetic Field Modelling

Since aeromagnetic surveying started immediately after World War II, a considerable area of the earth's surface both onshore (in excess of 25 million sq. km) has been magnetically surveyed. For about the first 15 years or so, fluxgate magnetometers were employed in aeromagnetic surveys, but the introduction of proton free-precession magnetometers resulted in absolute readings being recorded. Proton precession magnetometers have now been replaced to a large extent by the more sensitive optical absorption magnetometers. Some care has to be taken to calibrate aeromagnetic survey systems and this is best done using a calibration range tied to a magnetic observatory so that accuracies of 10nT or better are achieved for the total field values recorded. Survey navigation has always posed a problem for aeromagnetic surveys, especially offshore. Over land, vertically pointed 35 mm cameras were initially used to recover the aircraft track using a combination of aerial photos and topographic maps. Over featureless areas, it was necessary to utilize existing electronic positioning systems such as Loran C or set up special navigation systems. The advent of the satellite-based Global Positioning Systems (GPS) has to a larger extent solved the navigational problem because there is now almost continuous worldwide coverage to 10 m accuracy in the differential mode. The resultant aeromagnetic data is normally compiled into contour maps in which the diurnal variation and aircraft heading effects are removed. The resultant digital data are normally made publicly available both in gridded and profile form along with the published contour maps. Most aeromagnetic coverage has been obtained in the developed western countries, but elsewhere a considerable amount of surveying has been carried out; as an example, some 80 percent of Africa has been surveyed mostly as a result of aid programs. The data is usually held by the national geological survey or equivalent organizations, but in a number of cases the data (e.g., for the Magnetic Anomaly Map of North America) is also held by the World Data Centres.

Hood, Peter↗

NASA NTRS2006

Challenges to modeling the Sun-Earth System: A Workshop Summary

This special issue of the Journal of' Atmospheric and Solar-Terrestrial Physics is a compilation of 23 papers presented at The 2004 Huntsville Modeling Workshop: Challenges to Modeling thc San-Earth System held in Huntsville, AB on October 18-22, 2004. The title of the workshop appropriately captures the theme of what was presented and discussed by the 120 participants. Currently, end-to-end modeling of the Sun-Earth system is a major goal of the National Space Weather and NASA living with a star (LWS) programs. While profound advances have been made in modeling isolated regions of the Sun-Earth system, minimal progress has been achieved in modeling the end-to-end system. The transfer of mass, energy and momentum through the coupled Sun-Earth system spans a wide range of scales inn time and space. The uncertainty in the underlying physics responsible for coupling contiguous regions of the Sun-Earth system is recognized as a significant barrier to progress

Spann, James F.↗

NASA NTRS1971

Space shuttle low cost/risk avionics study

All work breakdown structure elements containing any avionics related effort were examined for pricing the life cycle costs. The analytical, testing, and integration efforts are included for the basic onboard avionics and electrical power systems. The design and procurement of special test equipment and maintenance and repair equipment are considered. Program management associated with these efforts is described. Flight test spares and labor and materials associated with the operations and maintenance of the avionics systems throughout the horizontal flight test are examined. It was determined that cost savings can be achieved by using existing hardware, maximizing orbiter-booster commonality, specifying new equipments to MIL quality standards, basing redundancy on cost effective analysis, minimizing software complexity and reducing cross strapping and computer-managed functions, utilizing compilers and floating point computers, and evolving the design as dictated by the horizontal flight test schedules.

Source record↗

NASA NTRS1989

Visual Information Processing for Television and Telerobotics

This publication is a compilation of the papers presented at the NASA conference on Visual Information Processing for Television and Telerobotics. The conference was held at the Williamsburg Hilton, Williamsburg, Virginia on May 10 to 12, 1989. The conference was sponsored jointly by NASA Offices of Aeronautics and Space Technology (OAST) and Space Science and Applications (OSSA) and the NASA Langley Research Center. The presentations were grouped into three sessions: Image Gathering, Coding, and Advanced Concepts; Systems; and Technologies. The program was organized to provide a forum in which researchers from industry, universities, and government could be brought together to discuss the state of knowledge in image gathering, coding, and processing methods.

Huck, Friedrich O.↗

NASA NTRS1999

MLP: A Parallel Programming Alternative to MPI for New Shared Memory Parallel Systems

Recent developments at the NASA AMES Research Center's NAS Division have demonstrated that the new generation of NUMA based Symmetric Multi-Processing systems (SMPs), such as the Silicon Graphics Origin 2000, can successfully execute legacy vector oriented CFD production codes at sustained rates far exceeding processing rates possible on dedicated 16 CPU Cray C90 systems. This high level of performance is achieved via shared memory based Multi-Level Parallelism (MLP). This programming approach, developed at NAS and outlined below, is distinct from the message passing paradigm of MPI. It offers parallelism at both the fine and coarse grained level, with communication latencies that are approximately 50-100 times lower than typical MPI implementations on the same platform. Such latency reductions offer the promise of performance scaling to very large CPU counts. The method draws on, but is also distinct from, the newly defined OpenMP specification, which uses compiler directives to support a limited subset of multi-level parallel operations. The NAS MLP method is general, and applicable to a large class of NASA CFD codes.

Taft, James R.↗

NASA NTRS2007

Web-Based Environment for Maintaining Legacy Software

Advanced Tool Integration Environment (ATIE) is the name of both a software system and a Web-based environment created by the system for maintaining an archive of legacy software and expertise involved in developing the legacy software. ATIE can also be used in modifying legacy software and developing new software. The information that can be encapsulated in ATIE includes experts documentation, input and output data of tests cases, source code, and compilation scripts. All of this information is available within a common environment and retained in a database for ease of access and recovery by use of powerful search engines. ATIE also accommodates the embedment of supporting software that users require for their work, and even enables access to supporting commercial-off-the-shelf (COTS) software within the flow of the experts work. The flow of work can be captured by saving the sequence of computer programs that the expert uses. A user gains access to ATIE via a Web browser. A modern Web-based graphical user interface promotes efficiency in the retrieval, execution, and modification of legacy code. Thus, ATIE saves time and money in the support of new and pre-existing programs.

Tigges, Michael↗

NASA NTRS1990

Calculating Performances Of Fabry-Perot Etalons

Effects of changes in design determined quickly. Etalon Model computer program implements stand-alone mathematical model of an etalon. Designed to perform calculations over many wavelengths. Used to determine sensitivity of filter to changes in temperature, thickness tolerances, or alignment angles of etalon design. Calculates several performance parameters of etalons by use of equations in closed form, and calculates transmission as function of wavelength and uses transmission data to determine additional performance parameters. Developed on IBM PS/2 Model 80-071 computer using Microsoft version 4.01 FORTRAN compiler.

Cross, Patricia L.↗

NASA NTRS1978

The programming language EFL

EFL is a comprehensive language designed to make it easy to write portable, understandable programs. It provides a rich set of data types and structures, a convenient operator set, and good control flow forms. The lexical form is easy to type and to read. Whenever possible, EFL uses the same forms that Ratfor does; in this sense EFL may be viewed as a superset of Ratfor. EFL is a well-defined language; this distinguishes it from most FORTRAN preprocessors which only add simple flow of control constructs to FORTRAN. The EFL compiler generates (possibly tailored) Standard FORTRAN as its output. EFL should catch and diagnose all syntax errors.

Feldman, S. I.↗

NASA NTRS1987

The Galilean satellite geological mapping program, 1986

The Galilean Satellite Geological Mapping Program was established to illuminate detailed geologic relations on the four large satellites of Jupiter. The program involves some 40 investigators from various universities, research institutes, and government offices in the United States, U.K., West Germany, and Italy. A total of 24 researchers was assigned to map 15 quadrangles on Ganymede, 15 to map 6 quadrangles on Io, and 3 to map 2 quadrangles on Europa. Maps of these three bodies are at a scale of 1:5 M except for three on Io that cover selected areas where high-resolution pictures permit compilation at 1:2 and 1:1 M scales. A 1:15,000,000 scale map of Callisto has been assigned; from it, quadrangles containing useful geologic information will be extracted later for mapping at a scale of 1:5,000,000.

Lucchitta, B. K.↗

NASA NTRS1997

A Generative Control Capability for a Model-based Executive

This paper describes Burton, a core element of a new generation of goal-directed model-based autonomous executives. This executive makes extensive use of component-based declarative models to analyze novel situations and generate novel control actions both at the goal and hardware levels. It uses an extremely efficient online propositional inference engine to efficiently determine likely states consistent with current observations and optimal target states that achieve high level goals. It incorporates a flexible generative control sequencing algorithm within the reactive loop to bridge the gap between current and target states. The system is able to detect and avoid damaging and irreversible situations, After every control action it uses its model and sensors to detect anomalous situations and immediately take corrective action. Efficiency is achieved through a series of model compilation and online policy construction methods, and by exploiting general conventions of hardware design that permit a divide and conquer approach to planning. The paper presents a formal characterization of Burton's capability, develops efficient algorithms, and reports on experience with the implementation in the domain of spacecraft autonomy. Burton is being incorporated as one of the key elements of the Remote Agent core autonomy architecture for Deep Space One, the first spacecraft for NASA's New Millenium program.

Williams, Brian C.↗

NASA NTRS2002

AVST Morphing Project Research Summaries in Fiscal Year 2001

The Morphing project at the National Aeronautics and Space Agency's Langley Research Center is part of the Aerospace Vehicle Systems Program Office that conducts fundamental research on advanced technologies for future flight vehicles. The objectives of the Morphing project are to develop and assess advanced technologies and integrated component concepts to enable efficient, multi-point adaptability in air and space vehicles. In the context of the project, the word "morphing" is defined as "efficient, multi-point adaptability" and may include micro or macro, structural or fluidic approaches. The current document on the Morphing project is a compilation of research summaries and other information on the project from fiscal year 2001. The focus of this document is to provide a brief overview of the project content, technical results and lessons learned from fiscal year 2001.

McGowan, Anna-Maria R.↗

NASA NTRS1988

Space station integrated propulsion and fluid systems study. Space station program fluid management systems databook

Commonality and integration of propulsion and fluid systems associated with the Space Station elements are being evaluated. The Space Station elements consist of the core station, which includes habitation and laboratory modules, nodes, airlocks, and trusswork; and associated vehicles, platforms, experiments, and payloads. The program is being performed as two discrete tasks. Task 1 investigated the components of the Space Station architecture to determine the feasibility and practicality of commonality and integration among the various propulsion elements. This task was completed. Task 2 is examining integration and commonality among fluid systems which were identified by the Phase B Space Station contractors as being part of the initial operating capability (IOC) and growth Space Station architectures. Requirements and descriptions for reference fluid systems were compiled from Space Station documentation and other sources. The fluid systems being examined are: an experiment gas supply system, an oxygen/hydrogen supply system, an integrated water system, the integrated nitrogen system, and the integrated waste fluids system. Definitions and descriptions of alternate systems were developed, along with analyses and discussions of their benefits and detriments. This databook includes fluid systems descriptions, requirements, schematic diagrams, component lists, and discussions of the fluid systems. In addition, cost comparison are used in some cases to determine the optimum system for a specific task.

Bicknell, B.↗

NASA NTRS2009

The 50 Constellation Priority Sites

The Constellation program (CxP) has developed a list of 50 sites of interest on the Moon which will be targeted by the LRO narrow angle camera. The list has also been provided to the M~ team to supplement their targeting list. This list does not represent a "site selection" process; rather the goal was to find "representative" sites and terrains to understand the range of possible surface conditions for human lunar exploration to aid engineering design and operational planning. The list compilers leveraged heavily on past site selection work (e.g. Geoscience and a Lunar Base Workshop - 1988, Site Selection Strategy for a Lunar Outpost - 1990, Exploration Systems Architecture Study (ESAS) - 2005). Considerations included scientific, resource utilization, and operational merits, and a desire to span lunar terrain types. The targets have been organized into two "tiers" of 25 sites each to provide a relative priority ranking in the event of mutual interference. A LEAG SAT (special action team) was established to validate and recommend modifications to the list. This SAT was chaired by Dr. Paul Lucey. They provided their final results to CxP in May. Dr. Wendell Mendell will organize an on-going analysis of the data as they come down to ensure data quality and determine if and when a site has sufficient data to be retired from the list. The list was compiled using the best available data, however, it is understood that with the flood of new lunar data, minor modifications or adjustments may be required.

Noble, S.↗

NASA NTRS1989

Advanced Software Development Workstation Project

The Advanced Software Development Workstation Project, funded by Johnson Space Center, is investigating knowledge-based techniques for software reuse in NASA software development projects. Two prototypes have been demonstrated and a third is now in development. The approach is to build a foundation that provides passive reuse support, add a layer that uses domain-independent programming knowledge, add a layer that supports the acquisition of domain-specific programming knowledge to provide active support, and enhance maintainability and modifiability through an object-oriented approach. The development of new application software would use specification-by-reformulation, based on a cognitive theory of retrieval from very long-term memory in humans, and using an Ada code library and an object base. Current tasks include enhancements to the knowledge representation of Ada packages and abstract data types, extensions to support Ada package instantiation knowledge acquisition, integration with Ada compilers and relational databases, enhancements to the graphical user interface, and demonstration of the system with a NASA contractor-developed trajectory simulation package. Future work will focus on investigating issues involving scale-up and integration.

Lee, Daniel↗

NASA NTRS1986

The Advanced Solar Observatory. Executive summary

The topics covered include the following: (1) an overview of the Advanced Solar Observatory program and instrumentation; (2) the scientific motivation for the Advanced Solar Observatory; (3) a brief review of recent advances in solar physics; (4) a scientific strategy for solar physics; (5) the scientific objectives of the Advanced Solar Observatory; (6) the configuration of the Advanced Solar Observatory; (7) the development of the Advanced Solar Observatory; (8) the performance of the Advanced Solar Observatory; (9) scientific operation of the Advanced Solar Observatory; and (10) present status of the Advanced Solar Observatory. A compilation of major scientific problems in solar physics is presented in the appendix.

Walker, A. B. C., Jr.↗