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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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Brief job-related autobiographical sketches of technicians working on NASA aerospace projects are presented. Career and educational guidance is offered to students thinking about entering the field of aerospace technology.
Brief job-related autobiographical sketches of engineers working on NASA aerospace projects are presented. Career and educational guidance is offered to students thinking about entering the aerospace field.
Brief job-related autobiographical sketches of scientists working on NASA space science projects are presented. Career and educational guidance is offered to students thinking about entering the space science field.
The STS-1 mission of the space shuttle is discussed. The launch and orbital operations are described, and the landing is reviewed.
Even though there are surveys in which annoyance decreases as the number of events increases above about 150 a day, the available evidence is not considered strong enough to reject the conventional assumption that reactions are related to the logarithm of the number of events. The data do not make it possible to reject the conventional assumption that the effects of the number of events and the peak noise level are additive. It is found that even when equivalent questionnaire items and definitions of noise events could be used, differences between the surveys' estimates of the effect of the number of events remained large. Three explanations are suggested for inconsistent estimates. The first has to do with errors in specifying the values of noise parameters, the second with the effects of unmeasured acoustical and area characteristics that are correlated with noise level or number, and the third with large sampling errors deriving from community differences in response to noise. It is concluded that significant advances in the knowledge about the effects of the number of noise events can be made only if surveys include large numbers of study areas.
The early years of space flight are discussed. An historical perspective is offered. Satellites and politics, management of large scale technology, the state of the literature of space, the domestic and international ramifications of space activity, and rationales for space exploration are discussed.
The space programs of the Soviet Union, Japan, and China are discussed. The types of launch vehicles they used and the classes of spacecraft they launched are examined. The political motivations of these nations are analyzed.
A brief accounting of MAP oriented research in the Republic of China is given. A stratosphere balloon launching facility and its capabilities are reviewed. Observations of the stratospheric aerosols with a balloon-borne aerosol computer were made. Long term monitoring of stratospheric aerosols induced by volcanic eruptions are made with a ruby lidar. The main parameters of an ST radar system are given. The ionospheric D region is investigated with the method of ionospheric absorption. And photochemical modeling and radiation parameterization of the middle atmosphere are made.
This bibliography contains 253 anotated references to reports and journal articles entered into the NASA scientific and technical information database 1984 to 1988.
This paper will present data related to software development processes and personnel involvement from the perspective of software quality assurance. We examine eight years of data collected from six projects. Data collected varied by project but usually included defect and fault density with limited use of code metrics, schedule adherence, and budget growth information. The data are a blend of AFSCP 800-14 and suggested productivity measures in Software Metrics: A Practioner's Guide to Improved Product Development. A software quality assurance database tool, SQUID, was used to store and tabulate the data.
This paper presents viewgraphs on Knowledge Management (KM) and how these interventions are put into practice by organizations and society. The topics include: 1) The Multiple Paradigm Tool; 2) Four Paradigms: tool for the Analyzing Organizations; 3) Assumptions About the Nature of Social Science; 4) Assumptions About the Nature of Society; 5) Schools of Sociological and Organizational Theory; 6) Meaning and Metaphors in the Four Paradigms; and 7) Possibilities and Conclusions.
Just imagine a mass storage system that consists of a machine with 2 CPUs, 1 Gigabyte (GB) of memory, 400 GB of disk space, 16800 cartridge tapes in the automated tape silos, 88,000 tapes located in the vault, and the software to manage the system. This system is designed to be a data repository; it will always have disk space to store all the incoming data. Currently 9.14 GB of new data per day enters the system with this rate doubling each year. To assure there is always disk space available for new data, the system. has to move data reside from the expensive disk to a much less expensive medium such as the 3480 cartridge tapes. Once the data is archived to tape, it should be able to move back to disk when someone wants to access it and the data movement should be transparent to the user. Now imagine all the tasks that a system administrator must perform to keep this system running 24 hour a day, 7 days a week. Since the filesystem maintains the illusion of unlimited disk space, data that comes to the system must get moved to tapes in an efficient manner. This paper will describe the mass storage system running at the Numerical Aerodynamic Simulation (NAS) at NASA Ames Research Center in both software and hardware aspects, then it will describe all of the tasks the system administrator has to perform on this system.
NASA's founding charter includes the requirement for reporting all scientific results to the public. This requirement is based on the principal that the exploration of space results in real benefits to humanity and that those benefits are to be shared as widely as practical. When NASA was founded, the traditional education and outreach methods were through the news media and the formal and informal (museums, planetariums exhibits, etc.) educational communities. With the nearly ubiquitous availability of the Internet, a third choice presents itself: communicating directly with individuals in their homes. This powerful approach offers benefits and pitfalls that must be addressed to be effective. This paper covers an integrated approach to providing high quality NASA research information to multiple audiences via a family of websites. The paper discuss the content generation, review, and production process and provide metrics on evaluating the results.
The MRO/HiRISE Operations Center provides a mechanism for Mars investigators to particaipate in selection of targets and access to the aquired images. Additional information is contained in the original extended abstract.
The NCCS's mass data storage system allows scientists to store and manage the vast amounts of data generated by these computations, and its high-speed network connections allow the data to be accessed quickly from the NCCS archives. Some NCCS users perform studies that are directly related to their ability to run computationally expensive and data-intensive simulations. Because the number and type of questions scientists research often are limited by computing power, the NCCS continually pursues the latest technologies in computing, mass storage, and networking technologies. Just as important as the processors, tapes, and routers of the NCCS are the personnel who administer this hardware, create and manage accounts, maintain security, and assist the scientists, often working one on one with them.
The first objective for this report was to perform a comprehensive research of industry models currently being used for similar purposes, in order to provide the Center with ideas of what is being done in area by private companies and government agencies. The second objective was to evaluate the use of taxonomies or ontologies to describe and catalog the areas of expertise at GSFC. The creation of a knowledge taxonomy is necessary for information extraction in order for The Expert Seeker to adequately search and find experts in a particular area of expertise. The requirements to develop a taxonomy are: provide minimal descriptive text; have the appropriate level of abstration; facilitate browsing; ease of use and speed of data entry are critical for success; customized to the organization and its culture; extent of knowledge areas; expandable, so new skills could be develop; could be complemented with free text fields to allow users the option to describe their knowledge in detail.
Twenty healthy elderly subjects (12 female, 8 male; mean age 81 years, range 67-87 years) each experienced a 15-day time isolation protocol in which they lived individually in a special laboratory apartment in which sleep and circadian rhythm measures could be taken. There were two experiments: one (6 females, 4 males) involved a 6-h phase advance of the sleep/wake cycle, and the other (6 females, 4 males) a 6-h phase delay. Each started with 5 baseline days, immediately followed by the phase shift. The subject was then held to the phase shifted routine for the remainder of the study. Rectal temperatures were recorded minute-by-minute throughout the entire experiment and each night of sleep was recorded using polysomnography. A directional asymmetry in phase-shift effects was apparent, with significantly more sleep disruption and circadian rhythm amplitude disruption after the phase advance than after the phase delay. Sleep disruption was reflected in reduced time spent asleep, and in changed REM latency, which increased in the phase advance direction but decreased in the phase delay direction. Although the phase advance led to a significant increase in wakefulness in the first half of the night, the phase delay did not lead to an equivalent increase in wakefulness during the second half of the night. Examination of both raw and 'demasked' circadian rectal temperature rhythms confirmed that phase adjustment was slow in both directions, but was less slow (and more monotonic) after the phase delay than after the phase advance. Subjective alertness suffered more disruption after the phase advance than after the phase delay.
To provide baseline data for various research studies at the University of Pittsburgh over a 10-year period, 266 healthy subjects (144 male, 122 female, aged 20-50 years) meeting certain criteria each completed a 14-night sleep diary. For each night, the diary allowed the subjective measurement of bedtime, wake time, time in bed (TIB), sleep efficiency, number of minutes of wake after sleep onset (WASO), alertness on awakening, and percentage of morning needing an alarm (or a person functioning as one). Weeknight versus weekend night differences in TIB (TIBdiff), weekday altertness, and reliance on alarms were examined as possible indicators of sleep debt. In addition, general descriptive data were tabulated. On average, bedtimes were at 23:48 and wake times at 07:23, yielding a mean TIB of 7 hours 35 minutes. As expected, bedtimes and wake times were later on weekend nights than on weeknights. Bedtimes were 26 minutes later, wake times 53 minutes later, yielding a mean weekend TIB increase of 27 minutes. Overall, subjects perceived their sleep latency to be 10.5 minutes, reported an average of one awakening during the night (with an average of 6.4 minutes of WASO), had a diary sleep efficiency of 96.3%, and awoke with an alterness rating of 69.5%. These variables differed little between weeknight and weekend nights. Subjects used an alarm (or a person functioning as an alarm) on 60.9% nights overall, 68.3% on weeknights, 42.5% on weekends. When TIBdiff was used as an estimate of sleep debt (comparing subjects with TIBdiff > 75 minutes with those with a TIBdiff < 30 minutes), the group with more "catch-up sleep" on weekends had shorter weeknight TIB durations (by about 24 minutes) and relied more on an alarm for weekday waking (by about 22%), indicating the possible utility of these variables as sleep debt indices.