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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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At least 37 records · Page 2
All sourcesNASA NTRSDOE OSTI
NASA NTRS2004

Recent Developments and Status of the Langley Single Vector Balance Calibration System (SVS)

The Langley Research Center (LaRC) Single Vector Balance Calibration System (SVS) was first introduced in 2000 by Peter Parker. The SVS combines the Design of Experiments (DOE) methodology with a novel load application system. Since that time three systems have been designed and developed with different load range capabilities (ranging from 2 pounds to 3,000 pounds). Approximately fifteen balances have been calibrated and their data compared to conventional techniques. This paper will present results of these comparisons, based on the mathematical models and accuracies, and discuss differences that were observed. In addition, changes in the implementation of the initial load schedules developed using DOE will be highlighted. One of the principles behind DOE is randomization. The initial loading schedules used to date have been randomized in the traditional DOE sense but not for repeat calibrations or experiments. Implementation of this randomization within blocks and its impact on data quality will be reviewed. Areas of potential future development will be presented which include changes in the centers to include loads with the force position system in the pure error estimates.

Jones, Shirley M.↗
NASA NTRS2017

Applications for Freeforms Optics at NASA

Review freeform optic applications as NASA. Describe design study results showing benefits of freeform optics to the instrument size, image quality, and field of view. Review areas of study and improvements needed to freeform manufacturing for future applications.

Design↗
NASA NTRS2010

Special Opportunities for Highly Sampled Areas

This slide presentation reviews the coverage areas for the two instruments that are scheduled to be on board the HyspIRI mission, (i.e.,visible to short wave infrared (VSWIR) and a multispectral thermal infrared (TIR) imager.)

Knox, Robert G.↗
NASA NTRS2016

Editorial: Reviewer Selection Process and New Areas of Expertise in GEMS

One method of selecting potential reviewers for papers submitted to the Journal of Geophysical Research Space Physics is to filter the user database within the Geophysical Electronic Manuscript System (GEMS) by areas of expertise. The list of these areas in GEMS can be self selected by users in their profile settings. The Editors have added 18 new entries to this list, an increase of 33 more than the previous 55 entries. All space physicists are strongly encouraged to update their profile settings in GEMS, especially their areas of expertise selections, and details of how to do this are provided.

Liemohn, Michael W.↗
NASA NTRS1979

Advanced missile technology. A review of technology improvement areas for cruise missiles

Technology assessments in the areas of aerodynamics, propulsion, and structures and materials for cruise missile systems are discussed. The cruise missiles considered cover the full speed, altitude, and target range. The penetrativity, range, and maneuverability of the cruise missiles are examined and evaluated for performance improvements.

Cronvich, L. L.↗
NASA NTRS1980

Plan of research for integrated soil moisture studies. Recommendations of the Soil Moisture Working Group

Soil moisture information is a potentially powerful tool for applications in agriculture, water resources, and climate. At present, it is difficult for users of this information to clearly define their needs in terms of accuracy, resolution and frequency because of the current sparsity of data. A plan is described for defining and conducting an integrated and coordinated research effort to develop and refine remote sensing techniques which will determine spatial and temporal variations of soil moisture and to utilize soil moisture information in support of agricultural, water resources, and climate applications. The soil moisture requirements of these three different application areas were reviewed in relation to each other so that one plan covering the three areas could be formulated. Four subgroups were established to write and compile the plan, namely models, ground-based studies, aircraft experiments, and spacecraft missions.

Source record↗
NASA NTRS1980

On the feasibility of quantitative ultrasonic determination of fracture toughness: A literature review

The three main topics covered are: (1) fracture toughness and microstructure, (2) quantitative ultrasonic and microstructure; and (3) scattering and related mathematical methods. Literature in these areas is reviewed to give insight to the search of a theoretical foundation for quantitative ultrasonic measurement of fracture toughness. The literature review shows that fracture toughness is inherently related to the microstructure and in particular, it depends upon the spacing of inclusions or second particles and the aspect ratio of second phase particles. There are indications that ultrasonic velocity attenuation measurements can be used to determine fracture toughness. The leads to a review of the mathematical models available in solving boundary value problems related to microstructural factors that govern facture toughness and wave motion. A framework towards the theoretical study for the quantitative determination of fracture toughness is described and suggestions for future research are proposed.

Fu, L. S.↗
NASA NTRS1972

Natural Resource Information System, remote sensing studies

Potential applications of remote sensing data were reviewed, and available imagery was interpreted to provide input to a demonstration data base. A literature review was conducted to determine the types and qualities of imagery required to satisfy identified data needs. Ektachrome imagery available over the demonstration areas was reviewed to establish the feasibility of interpreting cultural features, range condition, and timber type. Using the same imagery, a land use map was prepared for the demonstration area. The feasibility of identifying commercial timber areas using a density slicing technique was tested on multispectral imagery available for a portion of the demonstration area.

Leachtenauer, J.↗
NASA NTRS1962

Life Sciences Activities Associated with Project Mercury

Fifteen years of speculation and study concerning the problems of placing man into space flight produced a mass of reports which contemplated the hurdles and suggested solutions needed to permit safe flight. The accumulation of problems occurred in all disciplines. This could have been expected because the area of study was in the unknown, and speculation and calculation were the only methods of attack until flight data could be obtained. The Life Sciences community was as prolific in the identification of potential problem areas as the other scientific disciplines. The arrival of the era of manned space flight offers the opportunity to assess the problems directly and to define what is speculation and what is problem. This paper will discuss two areas of life sciences activities during the Project Mercury program. The first area will review the life-support activities associated with the spacecraft development and the provisions for the astronaut. The second area will present a summarization of the data concerning man's ability to live and work in this new environment and will attempt to present an analysis of the significance of the findings in light of future flights.

Physiological response↗
NASA NTRS1984

An aeroelastician's perspective of wind tunnel and flight experiences with active control of structural response and stability

Active controls technology is assessed based on a review of most of the wind-tunnel and flight tests and actual applications of active control concepts since the late sixties. The distinction is made between so-called ""rigid-body'' active control functions and those that involve significant modification of structural elastic response or stability. Both areas are reviewed although the focus is on the latter area. The basic goals and major results of the various studies or applications are summarized, and the anticipated use of active controls on current and near-future research and demonstration aircraft is discussed. Some of the ""holes'' remaining in the feasbility/benefits demonstration of active controls technology are examined.

Hanson, P. W.↗
NASA NTRS1982

VTOL and VSTOL handling qualities specifications, an overview of the current status

The highlights of a comparative analysis between the current helicopter and VSTOL specifications and four representative rotary wing aircraft are presented. Longitudinal, lateral, and directional control power and dynamic stability characteristics were analyzed for hovering conditions. Forward flight static and dynamic stability were analyzed for the longitudinal and lateral-directional axes. Results of the analyses in terms of the applicability/utility of the MIL-H-8501A criteria are presented for each of the above areas. The review of the MIL-H-8301A criteria against those in MIL-F-83300 and AGARD 577 indicate many areas in which MIL-H-8501A does not give adequate design guidance.

Goldstein, K. W.↗
NASA NTRS1985

Space shuttle handling qualities

The initial Orbiter handling qualities requirements, their effect on the vehicle design, and how it all turned out through the first six orbital missions are reviewed. Specific areas consisting of hand controller considerations and the wheelie problem are discussed. The requirements for the pitch axis subsonic flight control system are reviewed. Results of recent simulator evaluations to compare the existing system at landing with several other configurations are presented.

Gilbert, D. W.↗
NASA NTRS1975

A review and preliminary evaluation of methodological factors in performance assessments of time-varying aircraft noise effects

The effects of aircraft noise on human performance is considered. Progress is reported in the following areas: (1) review of the literature to identify the methodological and stimulus parameters involved in the study of noise effects on human performance; (2) development of a theoretical framework to provide working hypotheses as to the effects of noise on complex human performance; and (3) data collection on the first of several experimental investigations designed to provide tests of the hypotheses.

Coates, G. D.↗
NASA NTRS1976

Large Area Crop Inventory Experiment (LACIE). Review of LACIE methodology, a project evaluation of technical acceptability

The author has identified the following significant results. Results indicated that the LANDSAT data and the classification technology can estimate the small grains area within a sample segment accurately and reliably enough to meet the LACIE goals. Overall, the LACIE estimates in a 9 x 11 kilometer segment agree well with ground and aircraft determined area within these segments. The estimated c.v. of the random classification error was acceptably small. These analyses confirmed that bias introduced by various factors, such as LANDSAT spatial resolution, lack of spectral resolution, classifier bias, and repeatability, was not excessive in terms of the required performance criterion. Results of these tests did indicate a difficulty in differentiating wheat from other closely related small grains. However, satisfactory wheat area estimates were obtained through the reduction of the small grain area estimates in accordance with relative amounts of these crops as determined from historic data; these procedures are being further refined.

Source record↗
NASA NTRS2023

Quantitative Gas Property Measurements By Filtered Rayleigh Scattering: A Review

Filtered Rayleigh scattering (FRS) is a laser-based diagnostic technique used to nonintrusively quantify various thermodynamic properties of a light-scattering gas. The backbone of FRS is the molecular filtering of Rayleigh scattered light. This concept was initially introduced by the atmospheric LIDAR community before being adopted within the aerospace research field in the early 1990s. Since then, FRS has matured into a versatile quantitative diagnostic tool and has found use in a variety of flow regimes ranging from sub- to supersonic speeds in both reacting and nonreacting environments. This adoption can be attributed to the wealth of information that can be obtained via FRS, including the gas density, pressure, temperature, velocity, species composition, or, in some cases, several of these properties at once. This article reviews the current state of FRS methodology in recovering such gas properties. As knowledge of the fundamentals of Rayleigh scattering and spectral light filtering is crucial to the design of an FRS experiment, we begin by briefly reviewing these areas. Subsequently, we conduct a survey of experimental design strategies, assumptions, and data reduction methods used to measure different gas properties using FRS. We conclude the review with a short discussion on quantification of experimental uncertainty and future trends in FRS.

filtered Rayleigh scattering↗