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At least 613 records · Page 34
All sourcesNASA NTRSDOE OSTI
NASA NTRS1988

C3 generic workstation: Performance metrics and applications

The large number of integrated dependent measures available on a command, control, and communications (C3) generic workstation under development are described. In this system, embedded communications tasks will manipulate workload to assess the effects of performance-enhancing drugs (sleep aids and decongestants), work/rest cycles, biocybernetics, and decision support systems on performance. Task performance accuracy and latency will be event coded for correlation with other measures of voice stress and physiological functioning. Sessions will be videotaped to score non-verbal communications. Physiological recordings include spectral analysis of EEG, ECG, vagal tone, and EOG. Subjective measurements include SWAT, fatigue, POMS and specialized self-report scales. The system will be used primarily to evaluate the effects on performance of drugs, work/rest cycles, and biocybernetic concepts. Performance assessment algorithms will also be developed, including those used with small teams. This system provides a tool for integrating and synchronizing behavioral and psychophysiological measures in a complex decision-making environment.

Eddy, Douglas R.↗
NASA NTRS1986

Space Station Habitability Recommendations Based on a Systematic Comparative Analysis of Analogous Conditions

Conditions analogous to the proposed NASA Space Station are systematically analyzed in order to extrapolate design guidelines and recommendations concerning habitability and crew productivity. Analogous environments studied included Skylab, Sealab, Tektite, submarines, Antarctic stations and oil drilling platforms, among others. These analogues were compared and rated for size and composition of group, social organization, preparedness for mission, duration of tour, types of tasks, physical and psychological isolation, personal motivation, perceived risk, and quality of habitat and life support conditions. One-hundred design recommendations concerning, sleep, clothing, exercise, medical support, personal hygiene, food preparation, group interaction, habitat aesthetics, outside communications, recreational opportunities, privacy and personal space, waste disposal, onboard training, simulation and task preparation, and behavioral and physiological requirements associated with a microgravity environment, are provided.

Stuster, Jack W.↗
NASA NTRS1988

Igneous proceses and closed system evolution of the Tharsis region of Mars

A quantitative petrologic model for the evolution of the Tharsis region on Mars is presented, which is consistent with global gravity and topography data. It is demonstrated that it is possible to form and support the topographic relief of the Tharsis plateau by a closed-system mass-conservative nearly isostatic process involving generation of magmas from a mantle source region. Extrusion and/or intrusion (or underplating) of such magmas allows low-pressure solidification, with a consequent increase in volume relative to that which would be possible in the high-pressure source region, leading to elevated topology. The distribution of densities with depth obtained by the model is quantitatively consistent with the isostatic models of Sleep and Phillips (1979, 1985).

Finnerty, A. A.↗
NASA NTRS1988

A differential approach to microcomputer test battery development and implementation

The present microcomputer-based performance test battery emphasizes psychometric theory and utility for repeated-measures applications during extended exposure to various environmental stressors. In the menu that has been defined at the current state of this system's development, there are more than 30 'qualified' mental tests which stabilize in less than 10 min and possess test-retest reliabilities greater than 0.7 for a three-minute test/work period. The battery encompasses tests of cognition, information processing, psychomotor skill, memory, mood, etc. Several of the tests have demonstrated sensitivity to chemoradiotherapy, sleep loss, hypoxia, amphetamines, thermal stress, sensory deprivation, altitude, fatigue, and alcohol use. Recommendations are presented for 6-, 12-, and 22-min batteries.

Kennedy, R. S.↗
NASA NTRS1988

Aircrew fatigue and circadian rhythmicity

Recent statistical and experimental studies on the role of circadian rhythms in aircrew fatigue and aviation accidents are reviewed from a human-factors perspective, and typical data are presented in extensive graphs. Consideration is given to the biological clock and the limits of endurance, circadian desynchronization, sleep and sleepiness, short-haul and long-haul operational studies, and the potential advantages of cockpit automation.

Graeber, R. Curtis↗
NASA NTRS1988

On the wings of a dream: The Space Shuttle

Described are the organization and some of the interests and missions of NASA, the Space Transportation System, the Space Shuttle orbiter Enterprise, astronaut training and clothing, being launched into space, living and working in weightlessness, extravehicular activity, and the return from space to Earth. The various aspects of living in space are treated in considerable detail. This includes how the astronauts prepare food, how they eat and drink, how they sleep, exercise, change clothes and handle personal hygiene when in space.

Source record↗
NASA NTRS1989

Habitability during long-duration space missions - Key issues associated with a mission to Mars

Isolation and confinement conditions similar to those of a long-duration mission to Mars are examined, focusing on 14 behavioral issues with design implications. Consideration is given to sleep, clothing, exercise, medical support, personal hygiene, food preparation, group interaction, habitat aesthetics, outside communications, recreational opportunities, privacy, waste disposal, onboard training, and the microgravity environment. The results are used to develop operational requirements and habitability design guidelines for interplanetary spacecraft.

Stuster, Jack↗
NASA NTRS1990

Characteristics of trapped proton anisotropy at Space Station Freedom altitudes

The ionizing radiation dose for spacecraft in low-Earth orbit (LEO) is produced mainly by protons trapped in the Earth's magnetic field. Current data bases describing this trapped radiation environment assume the protons to have an isotropic angular distribution, although the fluxes are actually highly anisotropic in LEO. The general nature of this directionality is understood theoretically and has been observed by several satellites. The anisotropy of the trapped proton exposure has not been an important practical consideration for most previous LEO missions because the random spacecraft orientation during passage through the radiation belt 'averages out' the anisotropy. Thus, in spite of the actual exposure anisotropy, cumulative radiation effects over many orbits can be predicted as if the environment were isotropic when the spacecraft orientation is variable during exposure. However, Space Station Freedom will be gravity gradient stabilized to reduce drag, and, due to this fixed orientation, the cumulative incident proton flux will remain anisotropic. The anisotropy could potentially influence several aspects of Space Station design and operation, such as the appropriate location for radiation sensitive components and experiments, location of workstations and sleeping quarters, and the design and placement of radiation monitors. Also, on-board mass could possible be utilized to counteract the anisotropy effects and reduce the dose exposure. Until recently only omnidirectional data bases for the trapped proton environment were available. However, a method to predict orbit-average, angular dependent ('vector') trapped proton flux spectra has been developed from the standard omnidirectional trapped proton data bases. This method was used to characterize the trapped proton anisotropy for the Space Station orbit (28.5 degree inclination, circular) in terms of its dependence on altitude, solar cycle modulation (solar minimum vs. solar maximum), shielding thickness, and radiation effect (silicon rad and rem dose).

Armstrong, T. W.↗
NASA NTRS1991

Design methodology for a community response questionnaire on sonic boom exposure

A preliminary draft questionnaire concerning community response to sonic booms was developed. Interviews were conducted in two communities that had experienced supersonic overflights of the SR-71 airplane for several years. Even though the overflights had ceased about 6 months prior to the interviews, people clearly remembered hearing sonic booms. A total of 22 people living in central Utah and 23 people living along Idaho/Washington state border took part in these interviews. The draft questionnaire was constantly modified during the study in order to evaluate different versions. Questions were developed which related to annoyance, startle, sleep disturbance, building vibration, and building damage. Based on the data collected, a proposed community response survey response instrument was developed for application in a full-scale sonic boom study.

Farbry, John E., Jr.↗
NASA NTRS1990

Development of an Artificial Gravity Sleeper (AGS)

The design and construction of a 2-meter radius 'human compatible' centrifuge termed the Artificial Gravity Sleeper (AGS) is considered. The centrifuge will accommodate up to four subjects at a time, operate at a broad range of speeds, and have safety features. Experiments that will be conducted on the AGS will help to investigate the quality of sleep during 100 percent gradient centrifugation. A microgravity simulation also will be studied using bed rest to assess the ability of 100 percent gradient centrifugation to function as a countermeasure to cardiovascular deconditioning.

Cardus, David↗
NASA NTRS1992

Photic effects on sustained performance

Research is described which evaluates manipulating environmental light intensity as a means to attenuate fatigue. A counter balanced, within-subjects design was used to compare nine male subjects exposed to dim (100 lux) and bright (3000 lux) light conditions. Oral temperature values were greater for the bright light group over the dim light condition. Melatonin levels were suppressed by bright light treatment. Also, the frequency of eye blink rate was less for subjects during bright over dim light exposure. Light exposure was without effect on subjective fatigue. However, irrespective of light condition, significant effects on confusion, fatigue, and vigor mood dimensions were found as a result of 30 hour sleep deprivation. The findings suggest that bright lights may be used to help sustain nocturnal activity otherwise susceptible to fatigue. Such findings may have implications for the lighting arrangements on space flights during the subjective night for astronauts.

French, J.↗
NASA NTRS1991

Alertness management in flight operations - Strategic napping

Strategic napping in two different flight operation environments is considered to illustrate its application as a fatigue countermeasure. Data obtained from commercial short-haul and long-haul operations demonstrated the utility and current practices of strategic napping. A preplanned cockpit nap acted as an acute 'safety valve' for the sleep loss, circadian disruption, and fatigue that occurs in long-haul flying.

Rosekind, Mark R.↗
NASA NTRS1992

Therapeutic effectiveness of medications taken during spaceflight

The therapeutic effectiveness of medications during spaceflight is considered in light of extensive anecdotal and experimental evidence. Attention is given to a range of medications for space motion sickness, sleeplessness, and physical discomfort. About 70 individual cases are reviewed in which crewmembers used such medications as: (1) scopolamine hydrobromide, dextroamphetamine sulfate, and promethazine hydrochloride for motion sickness; (2) metoclopramide hydrochloride and naloxone hydrochloride for bowel motility; and (3) aspirin and acetaminophen for headache and back pain. The effectiveness of orally ingested medications for space motion sickness is shown to be very low, while promethazine hydrochloride is effective when administered intramuscularly. The medications for pain are shown to be generally effective, and the use of sleep-inducing medications is limited by potentially detrimental performance effects.

Pool, Sam L.↗
NASA NTRS1992

NASA Space Human Factors Program

This booklet briefly and succinctly treats 23 topics of particular interest to the NASA Space Human Factors Program. Most articles are by different authors who are mainly NASA Johnson or NASA Ames personnel. Representative topics covered include mental workload and performance in space, light effects on Circadian rhythms, human sleep, human reasoning, microgravity effects and automation and crew performance.

Source record↗
NASA NTRS1990

NASA/NSF Workshop on Antarctic Research

Viewgraphs that accompanied an Ames Research Center presentation address Ames' currently-supported life sciences activities. These include crew factor issues such as human, automation, and telecommunication systems; strategic behavior and workloads; sleep, fatigue, and circadian rhythms; and virtual reality and spatial instrumentation. The need, background, and examples of pertinent research are provided.

Connors, Mary M.↗
NASA NTRS1993

A comparison of low-gravity measurements on-board Columbia during STS-40

The first NASA Spacelab Life Sciences mission (SLS-1) flew 5 Jun. to 14 Jun. 1991 on the orbiter Columbia (STS-40). The purpose of the mission was to investigate the human body's adaptation to the low-gravity conditions of space flight and the body's readjustment after the mission to the 1 g environment of earth. In addition to the life sciences experiments manifested for the Spacelab module, a variety of experiments in other scientific disciplines flew in the Spacelab and in Get Away Special (GAS) Canisters on the GAS Bridge Assembly. Several principal investigators designed and flew specialized accelerometer systems to better assess the results of their experiments by means of a low-gravity environment characterization. This was also the first flight of the NASA Microgravity Science and Applications Division (MSAD) sponsored Space Acceleration Measurement System (SAMS) and the first flight of the NASA Orbiter Experiments Office (OEX) sponsored Orbital Acceleration Research Experiment accelerometer (OARE). A brief introduction to seven STS-40 accelerometer systems are presented and the resulting data are discussed and compared. During crew sleep periods, acceleration magnitudes in the 10(exp -6) to 10(exp -5) g range were recorded in the Spacelab module and on the GAS Bridge Assembly. Magnitudes increased to the 10(exp -4) g level during periods of nominal crew activity. Vernier thruster firings caused acceleration shifts on the order of 10(exp -4) g and primary thruster firings caused accelerations as great as 10(exp -2) g. Frequency domain analysis revealed typical excitation of Orbiter and Spacelab structural modes at 3.5, 4.7, 5.2, 6.2, 7, and 17 Hz.

Rogers, Melissa J. B.↗
NASA NTRS1993

Body fluid alterations during head-down bed rest in men at moderate altitude

To determine the effects of hypoxia on fluid balance responses to simulated zero-gravity, measurements were made in six subjects before and during -5 deg continuous head-down bed rest (HDBR) over 8 d at 10,678 ft. The same subjects were studied again at this altitude without HDBR as a control (CON) using a cross-over design. During this time, they maintained normal upright day-time activities, sleeping in the horizontal position at night. Fluid balance changes during HDBR in hypoxia were more pronounced than similar measurements previously reported from HDBR studies at sea level. Plasma volume loss was slightly greater and the diuresis and natriuresis were doubled in magnitude as compared to previous studies in normoxia and sustained for 4 d during hypoxia. These changes were associated with an immediate but transient rise in plasma atrial natriuretic peptide (ANP) to day 4 of 140 percent in HDBR and 41 percent in CON (p less than 0.005), followed by a decline towards baseline. Differences were less striking between HDBR and CON for plasma antidiuretic hormone and aldosterone, which were transiently reduced by HDBR. Plasma catecholamines showed a similar pattern to ANP in both HDBR and CON, suggesting that elevated ANP and catecholamines together accounted for the enhanced fluid shifts with HDBR during hypoxia.

Loeppky, J. A.↗
NASA NTRS1993

'And we were tired' fatigue and aircrew errors

Cooper, White, and Lauber analyzed jet-transport accidents worldwide for the period 1968 to 1976 and found more than 60 in which breakdowns of the crew-performance and decision-making process played a pivotal role. It is the contention of this paper that the results reported by Cooper, et al., are related to fatigue and that fatigue is related to sleep deprivation, circadian desynchronosis, and lack of good nutrition. It is further argued, and supporting research is cited, that fatigue does not cause loss of skill in flying the aircraft but may have disastrous effects on judgmental and decision-making functions.

Ritter, Richard D.↗