Search NASASearch

SEARCH · Search NASA

Results for “SYMPOSIA”

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 37 records · Page 2

Strategy for outer planets exploration

NASA's Planetary Programs Office formed a number of scientific working groups to study in depth the potential scientific return from the various candidate missions to the outer solar system. The results of these working group studies were brought together in a series of symposia to evaluate the potential outer planet missions and to discuss strategies for exploration of the outer solar system that were consistent with fiscal constraints and with anticipated spacecraft and launch vehicle capabilities. A logical, scientifically sound, and cost effective approach to exploration of the outer solar system is presented.

Source record

Research papers and publications (1981-1987): Workload research program

An annotated bibliography of the research reports written by participants in NASA's Workload Research Program since 1981 is presented, representing the results of theoretical and applied research conducted at Ames Research Center and at universities and industrial laboratories funded by the program. The major program elements included: 1) developing an understanding of the workload concept; 2) providing valid, reliable, and practical measures of workload; and 3) creating a computer model to predict workload. The goal is to provide workload-related design principles, measures, guidelines, and computational models. The research results are transferred to user groups by establishing close ties with manufacturers, civil and military operators of aerospace systems, and regulatory agencies; publishing scientific articles; participating in and sponsoring workshops and symposia; providing information, guidelines, and computer models; and contributing to the formulation of standards. In addition, the methods and theories developed have been applied to specific operational and design problems at the request of a number of industry and government agencies.

Hart, Sandra G.

Program of Research in Structures and Dynamics

The Structures and Dynamics Program was first initiated in 1972 with the following two major objectives: to provide a basic understanding and working knowledge of some key areas pertinent to structures, solid mechanics, and dynamics technology including computer aided design; and to provide a comprehensive educational and research program at the NASA Langley Research Center leading to advanced degrees in the structures and dynamics areas. During the operation of the program the research work was done in support of the activities of both the Structures and Dynamics Division and the Loads and Aeroelasticity Division. During the period of 1972 to 1986 the Program provided support for two full-time faculty members, one part-time faculty member, three postdoctoral fellows, one research engineer, eight programmers, and 28 graduate research assistants. The faculty and staff of the program have published 144 papers and reports, and made 70 presentations at national and international meetings, describing their research findings. In addition, they organized and helped in the organization of 10 workshops and national symposia in the structures and dynamics areas. The graduate research assistants and the students enrolled in the program have written 20 masters theses and 2 doctoral dissertations. The overall progress is summarized.

Source record

Human-computer interaction in distributed supervisory control tasks

An overview of activities concerned with the development and applications of the Operator Function Model (OFM) is presented. The OFM is a mathematical tool to represent operator interaction with predominantly automated space ground control systems. The design and assessment of an intelligent operator aid (OFMspert and Ally) is particularly discussed. The application of OFM to represent the task knowledge in the design of intelligent tutoring systems, designated OFMTutor and ITSSO (Intelligent Tutoring System for Satellite Operators), is also described. Viewgraphs from symposia presentations are compiled along with papers addressing the intent inferencing capabilities of OFMspert, the OFMTutor system, and an overview of intelligent tutoring systems and the implications for complex dynamic systems.

Mitchell, Christine M.

Preliminary results on the fracture analysis of multi-site cracking of lap joints in aircraft skins

This paper presents results of a fracture mechanics analysis relevant to fatigue crack growth at rivets in lap joints of aircraft skins are presented. Multi-site damage (MSD) is receiving increased attention within the context of problems of aging aircraft. Fracture analyses previously carried out include small-scale modeling of rivet/skin interactions, larger-scale two-dimensional models of lap joints similar to that developed here, and full scale three-dimensional models of large portions of the aircraft fuselage. Fatigue testing efforts have included flat coupon specimens, two-dimensional lap joint tests, and full scale tests on specimens designed to closely duplicate aircraft sections. Most of this work is documented in the proceedings of previous symposia on the aging aircraft problem. The effect MSD has on the ability of skin stiffeners to arrest the growth of long skin cracks is a particularly important topic that remains to be addressed. One of the most striking features of MSD observed in joints of some test sections and in the joints of some of the older aircraft fuselages is the relative uniformity of the fatigue cracks from rivet to rivet along an extended row of rivets. This regularity suggests that nucleation of the cracks must not be overly difficult. Moreover, it indicates that there is some mechanism which keeps longer cracks from running away from shorter ones, or, equivalently, a mechanism for shorter cracks to catch-up with longer cracks. This basic mechanism has not been identified, and one of the objectives of the work is to see to what extent the mechanism is revealed by a fracture analysis of the MSD cracks. Another related aim is to present accurate stress intensity factor variations with crack length which can be used to estimate fatigue crack growth lifetimes once cracks have been initiated. Results are presented which illustrate the influence of load shedding from rivets with long cracks to neighboring rivets with shorter cracks. Results will also be included for the effect of residual stress due to the riveting process itself. All the results presented in this paper should be regarded as preliminary in the sense that further work by ourselves and others will be required to validate them and to establish their sensitivity to more embellished modelling assumptions.

Aging Aircraft

Extended ecosystem signatures with application to Eos synergism requirements

The primary objective is to define the advantages of synergistically combining optical and microwave remote sensing measurements for the determination of biophysical properties important in ecosystem modeling. This objective was approached in a stepwise fashion starting with ground-based observations of controlled agricultural and orchard canopies and progressing to airborne observations of more natural forest ecosystems. This observational program is complemented by a parallel effort to model the visible reflectance and microwave scattering properties of composite vegetation canopies. The goals of the modeling studies are to verify our basic understanding of the sensor-scene interaction physics and to provide the basis for development of inverse models optimized for retrieval of key biophysical properties. These retrieval algorithms can then be used to simulate the expected performance of various aspects of Eos including the need for simultaneous SAR and HIRIS observations or justification for other (non-synchronous) relative timing constraints and the frequency, polarization, and angle of incidence requirements for accurate biophysical parameter extractions. This program completed a very successful series of truck-mounted experiments, made remarkable progress in development and validation of optical reflectance and microwave scattering models for vegetation, extended the scattering models to accommodate discontinuous and periodic canopies, developed inversion approaches for surface and canopy properties, and disseminated these results widely through symposia and journal publications. In addition, the third generation of the computer code for the microwave scattering models was provided to a number of other US, Canadian, Australian, and European investigators who are currently presenting and publishing results using the MIMICS research code.

Ulaby, Fawwaz T.

Proceedings of the Third Spaceborne Imaging Radar Symposium

This publication contains summaries of the papers presented at the Third Spaceborne Imaging Radar Symposium held at the Jet Propulsion Laboratory (JPL), California Institute of Technology, in Pasadena, California, on 18-21 Jan. 1993. The purpose of the symposium was to present an overview of recent developments in the different scientific and technological fields related to spaceborne imaging radars and to present future international plans. This symposium is the third in a series of 'Spaceborne Imaging Radar' symposia held at JPL. The first symposium was held in Jan. 1983 and the second in 1986.

Source record

The 1993 Shuttle Small Payloads Symposium

The 1993 Shuttle Small Payloads Symposium is a combined symposia of the Get Away Special (GAS), Hitchhiker, and Complex Autonomous Payloads (CAP) programs, and is proposed to continue as an annual conference. The focus of this conference is to educate potential Space Shuttle Payload Bay users as to the types of carrier systems provided and for current users to share experiment concepts.

Thomas, Lawrence R.

Basic principles of flight test instrumentation engineering, volume 1, issue 2

Volume 1 of the AG 300 series on ´Flight Test Instrumentation´ gives a general introduction to the basic principles of flight test instrumentation. The other volumes in the series provide more detailed treatments of selected topics on flight test instrumentation. Volume 1, first published in 1974, has been used extensively as an introduction for instrumentation courses and symposia, as well as being a reference work on the desk of most flight test and instrumentation engineers. It is hoped that this second edition, fully revised, will be used with as much enthusiasm as the first edition. In this edition a flight test system is considered to include both the data collection and data processing systems. In order to obtain an optimal data flow, the overall design of these two subsystems must be carefully matched; the detail development and the operation may have to be done by separate groups of specialists. The main emphasis is on the large automated instrumentation systems used for the initial flight testing of modern military and civil aircraft. This is done because there, many of the problems, which are discussed here, are more critical. It does not imply, however, that smaller systems with manual data processing are no longer used. In general, the systems should be designed to provide the required results at the lowest possible cost. For many tests which require only a few parameters, relatively simple systems are justified, especially if no complex equipment is available to the user. Although many of the aspects discussed in this volume apply to both small and large systems, aspects of the smaller systems are mentioned only when they are of special interest. The volume has been divided into three main parts. Part 1 defines the main starting points for the design of a flight test instrumentation system, as seen from the points of view of the flight test engineer and the instrumentation engineer. In Part 2 the discussion is concentrated on those aspects which apply to each individual measuring channel, and in Part 3 the main emphasis is on the integration of the individual data channels into one data collection system and on those aspects of the data processing which apply to the complete system.

channels (data transmission)

Overview of magnetospheric research

During the funding period for NASA Grant NAG5-1480 which prior to December, 1, 1990 was known as NASA Grant NAGW-78, the group has made substantial progress on the various topics originally proposed. The research performed has resulted in two Ph.D. Theses, more than 50 refereed papers in various journals and conference proceedings, and 31 invited and 104 contributed talks at conferences and symposia throughout the world. The main results from this work are summarized in each of the sections outlined in the original proposal, followed by a complete list of the group publications associated with this grant, a list of all invited talks given during the last three years, and finally a listing of the contributed talks. Research topics include global magnetohydrodynamic simulations, structure of the dayside magnetopause, merging at the dayside magnetopause, polar wind, plasma waves in the distant magnetotail, slow shocks in the distant magnetotail, collisionless tearing instabilities in the magnetotail, and other problems.

Ashour-Abdalla, Maha

The Long Duration Exposure Facility (LDEF) annotated bibliography

A major objective of the Space Act of 1958 which led to the establishment of the National Aeronautics and Space Administration (NASA) was the dissemination of science and technology. Today, under NASA administrator Daniel Goldin and the White House, there is a reemphasis on the dissemination and transfer of NASA science and technology to U.S. industry: both aerospace and non aerospace. The goal of this transfer of science and technology is to aid U.S. industries, making them more competitive in the global economy. After 69 months in space, LDEF provided new and important information on the space environment and how this hostile environment impacts spacecraft materials and systems. The space environment investigated by the LDEF researchers included: ionizing radiation, ultraviolet radiation, meteoroid and debris, atomic oxygen, thermal cycling, vacuum, microgravity, induced contamination and various synergistic effects. The materials used as part of LDEF and its experiments include polymers, metals, glass, paints and coatings. Fiber optic, mechanical, electrical, and optical systems were also used on LDEF. As part of the effort to disseminate and transfer LDEF science and technology, an annotated bibliographic database is being developed. This bibliography will be available electronically, as well as in hard copy. All LDEF domestic and foreign publications in the open literature, including scientific journals, the NASA LDEF Symposia volumes, books, technical reports and unrestricted contractor reports will be included in this database. The hard copy, as well as the electronic database, will be categorized by section in the scientific and technical discipline.

Levine, Arlene S.

Exploration of Venus and Mars Atmospheres; Symposium C2 and Symposium C5 of the COSPAR Plenary Meeting, 29th, Washington DC, 28 August - 5 September, 1992

Two symposia related to the exploration of the Venus and Mars atmospheres produced papers which described the results of spacecraft-based and ground-based observations of these two planets. The topics addressed included solar wind interactions, molecular ions, planetary magnetospheres, planetary ionospheres, planetary thermospheres, gravity waves, the homopause, radiative transfer, radiative balance, atmospheric water, planetary lightning, very low frequency bursts, cosmic-ray ionization, planetary loss, and future missions to study Mars aeronomy, energetic particles near Mars, radar exploration of Mars, and the Mars Environmental Survey (MESUR) mission.

Keating, G. M.

Fluid mechanics phenomena in microgravity; ASME Winter Annual Meeting, Anaheim, CA, Nov. 8-13, 1992

This paper is the first in a series of symposia presenting research activity in microgravity fluid mechanics. General topics addressed include two-phase flow and transport phenomena, thermo-capillary flow, and interfacial stability. Papers present mathmatical models of fluid dynamics in the microgravity environment. Applications suggested include space manufacturing and storage of liquids in low gravity.

Siginer, Dennis A.

The 1995 Shuttle Small Payloads Symposium

The 1995 Shuttle Small Payloads Symposium is a combined symposia of the Get Away Special (GAS) and Hitchhiker programs, and is proposed to continue as an annual conference. The focus of this conference is to educate potential Space Shuttle Payload Bay users as to the types of carrier systems provided and for current users to share experiment concepts.

Goldsmith, Frann

Standardization Activities in TMF Test Methodologies

No standard test practice currently exists for strain-controlled thermomechanical fatigue (TMF) testing. This paper discusses recent activities which lay the foundation for standardization of TMF test methods. Specifically, the paper documents the results of two interlaboratory TMF test programs, identifies key TMF symposia and workshops, and discusses efforts toward drafting a TMF standard test practice.

Verrilli, M. J.