Search NASA⌕ Search

SEARCH · Search NASA

Results for “draft”

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.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,117 records · Page 62
All sourcesNASA NTRSDOE OSTI
NASA NTRS1996

Development of Software to Model AXAF-I Image Quality

This draft final report describes the work performed under the delivery order number 145 from May 1995 through August 1996. The scope of work included a number of software development tasks for the performance modeling of AXAF-I. A number of new capabilities and functions have been added to the GT software, which is the command mode version of the GRAZTRACE software, originally developed by MSFC. A structural data interface has been developed for the EAL (old SPAR) finite element analysis FEA program, which is being used by MSFC Structural Analysis group for the analysis of AXAF-I. This interface utility can read the structural deformation file from the EAL and other finite element analysis programs such as NASTRAN and COSMOS/M, and convert the data to a suitable format that can be used for the deformation ray-tracing to predict the image quality for a distorted mirror. There is a provision in this utility to expand the data from finite element models assuming 180 degrees symmetry. This utility has been used to predict image characteristics for the AXAF-I HRMA, when subjected to gravity effects in the horizontal x-ray ground test configuration. The development of the metrology data processing interface software has also been completed. It can read the HDOS FITS format surface map files, manipulate and filter the metrology data, and produce a deformation file, which can be used by GT for ray tracing for the mirror surface figure errors. This utility has been used to determine the optimum alignment (axial spacing and clocking) for the four pairs of AXAF-I mirrors. Based on this optimized alignment, the geometric images and effective focal lengths for the as built mirrors were predicted to cross check the results obtained by Kodak.

Ahmad, Anees↗
NASA NTRS1995

The IUE Mega Campaign: Wind Variability and Rotation in Early-Type Stars

Wind variability in OB stars may be ubiquitous and a connection between projected stellar rotation velocity and wind activity is well established. However, the origin of this connection is unknown. To probe the nature of the rotation connection, several of the attendees at the workshop on Instability and Variability of Hot-Star Winds drafted an IUE observing proposal. The goal of this program was to follow three stars for several rotations to determine whether the rotation connection is correlative or causal. The stars selected for monitoring all have rotation periods less than or equal to 5 days. They were HD 50896 (WN5), HD 64760 (BO.5 Ib), and HD 66811 (zeta Pup; 04 If(n)). During 16 days of nearly continuous observations in 1995 January (dubbed the 'MEGA' campaign), 444 high-dispersion IUE spectra of these stars were obtained. This Letter presents an overview of the results of the MEGA campaign and provides an introduction to the three following Letters, which discuss the results for each star.

Massa, D.↗
NASA NTRS1995

Development of CFC-Free Cleaning Processes at the NASA White Sands Test Facility

The NASA White Sands Test Facility (WSTF) is developing cleaning and verification processes to replace currently used chlorofluorocarbon-113- (CFC-113-) based processes. The processes being evaluated include both aqueous- and solvent-based techniques. The presentation will include the findings of investigations of aqueous cleaning and verification processes that are based on a draft of a proposed NASA Kennedy Space Center (KSC) cleaning procedure. Verification testing with known contaminants, such as hydraulic fluid and commonly used oils, established correlations between nonvolatile residue and CFC-113. Recoveries ranged from 35 to 60 percent of theoretical. WSTF is also investigating enhancements to aqueous sampling for organics and particulates. Although aqueous alternatives have been identified for several processes, a need still exists for nonaqueous solvent cleaning, such as the cleaning and cleanliness verification of gauges used for oxygen service. The cleaning effectiveness of tetrachloroethylene (PCE), trichloroethylene (TCE), ethanol, hydrochlorofluorocarbon-225 (HCFC-225), tert-butylmethylether, and n-Hexane was evaluated using aerospace gauges and precision instruments and then compared to the cleaning effectiveness of CFC-113. Solvents considered for use in oxygen systems were also tested for oxygen compatibility using high-pressure oxygen autoignition and liquid oxygen mechanical impact testing.

Beeson, Harold↗
NASA NTRS1995

MPI-IO: A Parallel File I/O Interface for MPI Version 0.3

Thanks to MPI [9], writing portable message passing parallel programs is almost a reality. One of the remaining problems is file I/0. Although parallel file systems support similar interfaces, the lack of a standard makes developing a truly portable program impossible. Further, the closest thing to a standard, the UNIX file interface, is ill-suited to parallel computing. Working together, IBM Research and NASA Ames have drafted MPI-I0, a proposal to address the portable parallel I/0 problem. In a nutshell, this proposal is based on the idea that I/0 can be modeled as message passing: writing to a file is like sending a message, and reading from a file is like receiving a message. MPI-IO intends to leverage the relatively wide acceptance of the MPI interface in order to create a similar I/0 interface. The above approach can be materialized in different ways. The current proposal represents the result of extensive discussions (and arguments), but is by no means finished. Many changes can be expected as additional participants join the effort to define an interface for portable I/0. This document is organized as follows. The remainder of this section includes a discussion of some issues that have shaped the style of the interface. Section 2 presents an overview of MPI-IO as it is currently defined. It specifies what the interface currently supports and states what would need to be added to the current proposal to make the interface more complete and robust. The next seven sections contain the interface definition itself. Section 3 presents definitions and conventions. Section 4 contains functions for file control, most notably open. Section 5 includes functions for independent I/O, both blocking and nonblocking. Section 6 includes functions for collective I/O, both blocking and nonblocking. Section 7 presents functions to support system-maintained file pointers, and shared file pointers. Section 8 presents constructors that can be used to define useful filetypes (the role of filetypes is explained in Section 2 below). Section 9 presents how the error handling mechanism of MPI is supported by the MPI-IO interface. All this is followed by a set of appendices, which contain information about issues that have not been totally resolved yet, and about design considerations. The reader can find there the motivation behind some of our design choices. More information on this would definitely be welcome and will be included in a further release of this document. The first appendix contains a description of MPI-I0's 'hints' structure which is used when opening a file. Appendix B is a discussion of various issues in the support for file pointers. Appendix C explains what we mean in talking about atomic access. Appendix D provides detailed examples of filetype constructors, and Appendix E contains a collection of arguments for and against various design decisions.

Corbett, Peter↗
NASA NTRS1997

Introduction to Solid Edge(TM)

Solid Edge was conceived and developed to provide breakthrough levels of productivity for engineers and designers by providing tools focused on their daily work. This user-oriented approach led to a focus on five key areas: 1) assembly-focused design, 2) ease of use, 3) plug and play software, 4) superior part modeling, and 5) production drafting. Mechanical designers work primarily with assemblies of parts that together perform a useful function. The parts themselves are principally a consequence of the function of the assembly and the interrelationships between parts. Breakthroughs in productivity will come through a focus on making the design of assemblies easier, with enhanced part design a prerequisite to that. Enhancements already in development are part to part interaction, more assembly features applying to multiple parts, exploded assemblies, assembly playback, enhanced BOM, etc.

Smith, John C.↗
NASA NTRS1997

Research to Support the Determination of Spacecraft Maximum Acceptable Concentrations of Potential Atmospheric Contaminants

In many ways, the typical approach to the handling of bibliographic material for generating review articles and similar manuscripts has changed little since the use of xerographic reproduction has become widespread. The basic approach is to collect reprints of the relevant material and place it in folders or stacks based on its dominant content. As the amount of information available increases with the passage of time, the viability of this mechanical approach to bibliographic management decreases. The personal computer revolution has changed the way we deal with many familiar tasks. For example, word processing on personal computers has supplanted the typewriter for many applications. Similarly, spreadsheets have not only replaced many routine uses of calculators but have also made possible new applications because the cost of calculation is extremely low. Objective The objective of this research was to use personal computer bibliographic software technology to support the determination of spacecraft maximum acceptable concentration (SMAC) values. Specific Aims The specific aims were to produce draft SMAC documents for hydrogen sulfide and tetrachloroethylene taking maximum advantage of the bibliographic software.

Orr, John L.↗
NASA NTRS1997

Solar Cell Calibration and Measurement Techniques

The increasing complexity of space solar cells and the increasing international markets for both cells and arrays has resulted in workshops jointly sponsored by NASDA, ESA and NASA. These workshops are designed to obtain international agreement on standardized values for the AMO spectrum and constant, recommend laboratory measurement practices and establish a set of protocols for international comparison of laboratory measurements. A working draft of an ISO standard, WDI 5387, 'Requirements for Measurement and Calibration Procedures for Space Solar Cells' was discussed with a focus on the scope of the document, a definition of primary standard cell, and required error analysis for all measurement techniques. Working groups addressed the issues of Air Mass Zero (AMO) solar constant and spectrum, laboratory measurement techniques, and the international round robin methodology. A summary is presented of the current state of each area and the formulation of the ISO document.

Bailey, Sheila↗
NASA NTRS1998

A Search for Hydrodynamical Interaction Between the ISM and Radio Jets in IC4296

The ROSAT HRI Data set on IC 4296 has been reduced and analysed. A draft paper on the small-scale structure of x-ray emission and its relation to the radio emission has been written. Mackie left the Smithsonian Astrophysical Observatory in September 1997 and in January 1998 he joined the staff at Carter Observatory, New Zealand. Mackie is currently (May 1998) upgrading computer software at Carter to run IRAF-PROS and XSPEC x-ray software packages in order to reduce and analyze archival ROSAT PSPC data on IC 4296. The PSPC results are needed to investigate the hot gas temperature and abundance properties that will be used in conjunction with the radio jet properties to determine the hydrodynamical interaction status of IC 4296, and finalize the results of a research paper.

Mackie, Glen↗
NASA NTRS1998

Reference Mission Version 3.0 Addendum to the Human Exploration of Mars: The Reference Mission of the NASA Mars Exploration Study Team

This Addendum to the Mars Reference Mission was developed as a companion document to NASA Special Publication 6107, “Human Exploration of Mars: The Reference Mission of the NASA Exploration Study Team.” The Addendum summarizes changes and updates to the Mars Reference Mission the Exploration Office developed since the final draft of SP 6107 was printed in early 1998. The Reference Mission is a tool used by the Exploration Team and the exploration community to compare and evaluate approaches to mission and system concepts that could be used for human exploration missions. It is intended to identify and clarify system “drivers,” or significant sources of cost, performance, risk, and schedule variation. It does not represent a final or recommended approach to human Mars missions. Several alternative scenarios, including human exploration missions to the Moon, asteroids, or other targets beyond Earth orbit as well as employing different technical approaches to solving mission and technology challenges, are currently under study by the Exploration Team. Comparing alternative approaches provides the basis for continual improvement to technology investment plans and general understanding of future human exploration missions. The Addendum represents a “snapshot” of work in progress in support of planning for future human exploration missions through May 1998. Annual publications of revisions to the Reference Mission are planned beginning in late 1998.

Mars↗
NASA NTRS1998

[MODIS Investigation]

The objective of the last six months were: (1) Continue analysis of Hawaii Ocean Time-series (HOT) bio-optical mooring data, and Southern Ocean bio-optical drifter data; (2) Complete development of documentation of MOCEAN algorithms and software for use by MOCEAN team and GLI team; (3) Deploy instrumentation during JGOFS cruises in the Southern Ocean; (4) Participate in test cruise for Fast Repetition Rate (FRR) fluorometer; (5) Continue chemostat experiments on the relationship of fluorescence quantum yield to environmental factors; and (6) Continue to develop and expand browser-based information system for in situ bio-optical data. We are continuing to analyze bio-optical data collected at the Hawaii Ocean Time Series mooring as well as data from bio-optical drifters that were deployed in the Southern Ocean. A draft manuscript has now been prepared and is being revised. A second manuscript is also in preparation that explores the vector wind fields derived from NSCAT measurements. The HOT bio-optical mooring was recovered in December 1997. After retrieving the data, the sensor package was serviced and redeployed. We have begun preliminary analysis of these data, but we have only had the data for 3 weeks. However, all of the data were recovered, and there were no obvious anomalies. We will add second sensor package to the mooring when it is serviced next spring. In addition, Ricardo Letelier is funded as part of the SeaWiFS calibration/validation effort (through a subcontract from the University of Hawaii, Dr. John Porter), and he will be collecting bio-optical and fluorescence data as part of the HOT activity. This will provide additional in situ measurements for MODIS validation. As noted in the previous quarterly report, we have been analyzing data from three bio-optical drifters that were deployed in the Southern Ocean in September 1996. We presented results on chlorophyll and drifter speed. For the 1998 Ocean Sciences meeting, a paper will be presented on this data set, focusing on the diel variations in fluorescence quantum yield. Briefly, there are systematic patterns in the apparent quantum yield of fluorescence (defined as the slope of the line relating fluorescence/chlorophyll and incoming solar radiation). These systematic variations appear to be related to changes in the circulation of the Antarctic Polar Front which force nutrients into the upper ocean. A more complete analysis will be provided in the next Quarterly report.

Abbott, Mark R.↗
NASA NTRS1998

OhioView: Distribution of Remote Sensing Data Across Geographically Distributed Environments

Various issues associated with the distribution of remote sensing data across geographically distributed environments are presented in viewgraph form. Specific topics include: 1) NASA education program background; 2) High level architectures, technologies and applications; 3) LeRC internal architecture and role; 4) Potential GIBN interconnect; 5) Potential areas of network investigation and research; 6) Draft of OhioView data model; and 7) the LeRC strategy and roadmap.

Ramos, Calvin T.↗
NASA NTRS1998

Algorithm for Estimating the Plume Centerline Temperature and Ceiling Jet Temperature in the Presence of a Hot Upper Layer

The experiments were designed to provide insight into the behavior of jet fuel fires in aircraft hangars and to study the impact of these fires on the design and operation of a variety of fire protection systems. As a result, the test series included small fires designed to investigate the operation of UV/IR detectors and smoke detectors as well as large fires which were used to investigate the operation of ceiling mounted heat detectors and sprinklers. The impact of the presence or absence of draft curtains was also studied in the 15 m hangar. It is shown that in order to predict the plume centerline temperature within experimental uncertainty, the entrainment of the upper layer gas must be modeled. For large fires, the impact of a changing radiation fraction must also be included in the calculation. The dependence of the radial temperature profile of the ceiling jet as a function of layer development is demonstrated and a ceiling jet temperature algorithm which includes the impact of a growing layer is developed.

ALGORITHMS↗
NASA NTRS1959

Hydrodynamic Impact-Load Alleviation with a Penetrating Hydro-Ski

A penetrating hydro-ski was mounted below a model tested previously in the study reported in NACA Technical Note 4401, and a series of impacts were made in the Langley impact basin to determine load alleviation with this type of hydro-ski. The hydro-ski was designed to penetrate through seaway irregularities with a minimum of drag and with small impact loads. The penetrating hydro-ski was small (beam-loading coefficient of 111) and of a streamline shape with the bottom designed for flush retraction into the main model. A series of impacts at fixed trim angles of 8, 16, and 30 deg were made in smooth water and at a fixed trim angle of 8 deg in rough water. The loads and motions of the model were recorded, and photographic observations of the flow and cavities generated in the water by the penetrating hydro-ski were made. The data are presented and the maximum impact loads and maximum drafts of the model with the penetrating hydro-ski are compared with those of the model obtained without the penetrating hydro-ski. Maximum load reductions of 30 to 70 percent in smooth water and of 50 to 80 percent in rough water are indicated. Cavity and flow generation by the penetrating hydro-ski are discussed, and it is indicated that the penetrating hydro-ski moved smoothly through the water and generated deep cavities which are shown by stereophotographs.

Edge, Philip M., Jr.↗
NASA NTRS1959

Effect of Convex Longitudinal Curvature on the Planing Characteristics of a Surface Without Dead Rise

A hydrodynamic investigation was made in Langley tank no. 1 of a planing surface which was curved longitudinally in the shape of a circular arc with the center of curvature above the model and had a beam of inches and a radius of curvature of 20 beams. The planing surface had length-beam ratio of 9 and an angle of dead rise of 0 deg. Wetted length, resistance, and trimming moment were determined for values of load coefficient C(sub Delta) from -4.2 to 63.9 and values of speed coefficient C(sub V) from 6 to 25. The effects of convexity were to increase the wetted length-beam ratio (for a given lift), to decrease the lift-drag ratio, to move the center of pressure forward, and ta increase the trim for maximum lift-drag ratio as compared with values for a flat surface. The effects were greatest at low trims and large drafts. The maximum negative lift coefficient C(sub L,b) obtainable with a ratio of the radius of curvature to the beam of 20 was -0.02. The effects of camber were greater in magnitude for convexity than for the same amount of concavity.

Mottard, Elmo J.↗
NASA NTRS1998

Testing and Further Development of Improved Etches and Etching Methods for the Analysis of Bridgman Grown Semiconductor Crystals with an Emphasis on Lead-Tin-Telluride

The goals outlined for the research project for this year have been completed, and the following supporting documentation is attached: 1. A copy of the proposal outlining the principal goals: (a) Improve the characterization of semiconductor crystals through new etches and etching procedures. (b) Developed a novel voltammetric method to characterize semiconductor crystals as a result of searching for improved etches for lead-tin-telluride. (c) Presented paper at ACCG- 10. (d) Prepared manuscripts for publication. Completed additional testing suggested by reviewers and re-submitted manuscripts. (e) Worked with an undergraduate student on this project to provide her an opportunity to have a significant research experience prior to graduation. 2. In addition to the anticipated goals the following were also accomplished: (a) Submitted the newly developed procedures for consideration as a patent or a NASA Tech Brief. (b) Submitted a paper for presentation at the forthcoming ICCG- 12 conference. 3. A copy of the final draft of the publication as submitted to the editors of the Journal of Crystal Growth.

Barber, Patrick G.↗
NASA NTRS1998

OCTS and SeaWiFS Bio-Optical Algorithm and Product Validation and Intercomparison in US Coastal Waters

The successful launch of the National Space Development Agency of Japan (NASDA) Ocean Color and Temperature Sensor (OCTS) in August 1996, and the launch of Orbital Science Corporation's (OSC) Sea-viewing Wide-Field-of-view Sensor (SeaWiFS) in August 1997 signaled the beginning of a new era for ocean color research and application. These data may be used to remotely evaluate 1) water quality, 2) transport of sediments and adhered pollutants, 3) primary production, upon which commercial shellfish and finfish populations depend for food, and 4) harmful algal blooms which pose a threat to public health and economies of affected areas. Several US government agencies have recently expressed interest in monitoring U.S. coastal waters using optical remote sensing. This renewed interest is broadly driven by 1) resource management concerns over the impact of coastward shifts in population and land use on the ecosystems of estuaries, wetlands, nearshore benthic environments and fisheries, 2) recognition of the need to understand short time scale global change due to urbanization of sensitive land-margin ecosystems, and 3) national security issues. Satellite ocean color sensors have the potential to furnish data at the appropriate time and space scales to evaluate and resolve these concerns and problems. In this draft technical memorandum, we outline our progress during the first year of our SIMBIOS project to evaluate ocean color bio-optical algorithms and products generated using OCTS and SeaWiFS data in coastal US waters.

Brown, Christopher W.↗
NASA NTRS1992

Legislative Origins of the National Aeronautics and Space Act of 1958

A transcript of a 1992 collective oral history with several individuals who helped to draft the Space Act in 1958 is presented. Contributors include: Paul G. Dembling, Willis H. Shapley, Eilene M. Galloway, Glen P. Wilson, George Reedy, H. Guyford Stever and George Siegel.

Logsdon, John M.↗
NASA NTRS1998

EGRET High Energy Capability and Multiwavelength Flare Studies and Solar Flare Proton Spectra

The accomplishments of the participation in the Compton Gamma Ray Observatory Guest investigator program is summarized in this report. The work involved the study of Energetic Gamma Ray Experiment Telescope (EGRET)/Total Absorption Shower Counter(TASC) flare data. The specific accomplishments were the use of the accelerator neutron measurements obtained at the University of New Hampshire to verify the TASC response function and to modify the TASC fitting program to include a high energy neutron contribution, and to determine a high energy neutron contribution to the emissions from the 1991 June 11, solar flare. The next step in the analysis of this event was doing fits to the TASC energy-loss spectra as a function of time. A significant hardening of the solar proton spectrum over time was found for the flare. Further data was obtained from the Yohkoh HXT time histories and images for the 1991 October 27 flare. The results to date demonstrate that the TASC spectral analysis contributes crucial information on the particle spectrum interacting at the Sun. The report includes a paper accepted for publication, a draft of a paper to be delivered at the 26th International Cosmic Ray Conference and an abstract of a paper to be presented at the Meeting of the American Physical Society.

Chupp, Edward L.↗