4,041 research outputs found
Transpirationally cooled heat ablation system Patent
Transpirationally cooled heat ablation system for interplanetary spacecraft reentry shieldin
Research study for gel precursors as glass and ceramic starting materials for space processing applications research
The development of techniques for the preparation of glass and ceramic starting materials that will result in homogeneous glasses or ceramic products when melted and cooled in a containerless environment is described. Metal-organic starting materials were used to make compounds or mixtures which were then decomposed by hydrolysis reactions to the corresponding oxides. The sodium tungstate system was chosen as a model for a glass with a relatively low melting temperature. The alkoxide tungstates also have interesting optical properties. For all the compositions studied, comparison samples were prepared from inorganic starting materials and submitted to the same analyses
Using permeable membranes to produce hydrogen and oxygen from water
Concept may make it profitable to obtain hydrogen fuel from water. Laboratory tests have demonstrated that method enables decomposition of water several orders of magnitude beyond equilibrium state where only small amounts of free hydrogen are present
Time maintenance of user clocks via the tracking and data relay satellite system
A system is described which uses the Tracking and Data Relay Satellite System (TDRSS) itself to compare the user satellite clock with a clock at the White Sands station that is referenced to Universal Time Coordinated (UTC). No command of the spacecraft by the system is required, and actual on-board clock corrections are made by the spacecraft control center at its discretion. Computer models were constructed using basic orbital parameters for user and TDRS satellites. With only first-order corrections and simple averaging techniques for constant clock rates, error measurement precision of better than one microsecond was obtained. More sophisticated computations should allow considerable improvement over this
An evaluation: The potential of discarded tires as a source of fuel
The destructive distillation of rubber tire samples was studied by thermogravimetry, differential scanning calorimetry, combustion calorimetry, and mass spectroscopy. The decomposition reaction was found to be exothermic and produced a mass loss of 65 percent. The gas evolution curves that were obtained indicate that a variety of organic materials are evolved simultaneously during the decomposition of the rubber polymer
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Earth Science Informatics Community Requirements for Improving Sustainable Science Software Practices: User Perspectives and Implications for Organizational Action
Science software is integral to the scientific process and must be developed and managed in a sustainable manner to ensure future access to scientific data and related resources. Organizations that are part of the scientific enterprise, as well as members of the scientific community who work within these entities, can contribute to the sustainability of science software and to practices that improve scientific community capabilities for science software sustainability. As science becomes increasingly digital and therefore, dependent on software, improving community practices for sustainable science software will contribute to the sustainability of science. Members of the Earth science informatics community, including scientific data producers and distributers, end-user scientists, system and application developers, and data center managers, use science software regularly and face the challenges and the opportunities that science software presents for the sustainability of science. To gain insight on practices needed for the sustainability of science software from the science software experiences of the Earth science informatics community, an interdisciplinary group of 300 community members were asked to engage in simultaneous roundtable discussions and report on their answers to questions about the requirements for improving scientific software sustainability. This paper will present an analysis of the issues reported and the conclusions offered by the participants. These results provide perspectives for science software sustainability practices and have implications for actions that organizations and their leadership can initiate to improve the sustainability of science software
Earth resources-regional transfer activity contracts review
A regional transfer activity contracts review held by the Earth Resources Office was summarized. Contracts in the earth resources field primarily directed toward applications of satellite data and technology in solution of state and regional problems were reviewed. A summary of the progress of each contract was given in order to share experiences of researchers across a seven state region. The region included Missouri, Kentucky, Tennessee, Mississippi, Alabama, Georgia, and North Carolina. Research in several earth science disciplines included forestry, limnology, water resources, land use, geology, and mathematical modeling. The use of computers for establishment of information retrieval systems was also emphasized
How political parties adjust to fixed voter opinions
We propose a new version of the spatial model of voting. Platforms of five
parties are evolving in a two-dimensional landscape of political issues so as
to get maximal numbers of voters. For a Gaussian landscape the evolution leads
to a spatially symmetric state, where the platform centers form a pentagon
around the Gaussian peak. For a bimodal landscape the platforms located at
different peaks get different numbers of voters.Comment: 8 pages, 3 figures. Accepted in Int. J. Modern Phys.
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Community Recommendations for Improving Sustainable Scientific Software Practices
Multiple focus groups were conducted to elicit perspectives from members of the Earth science informatics community on the sustainability of scientific software. Recommendations that the participants offered for near-term community actions and activities are described
Let them speak for themselves: Improving adolescent self-report rate on pre-visit screening
Background
Adolescent pre-visit screening on patient-generated health data is a common and efficient practice to guide clinical decision making. However, proxy informants (e.g., parents or caregivers) often complete these forms, which may lead to incorrect information or lack of confidentiality. Our objective was to improve the adolescent self-report rate on pre-visit screening.
Methods
We conducted an interventional study using an interrupted time-series design to compare adolescent self-report rates (percent of adolescents ages 12-18 years completing their own pre-visit screening) over 16 months in general pediatric ambulatory clinics. We collected data using a computerized clinical decision support system with waiting room electronic tablet screening. Pre-intervention rates were low, and we created and implemented two electronic workflow alerts, one each to the patient/caregiver and clinical staff, reminding them that the adolescent should answer the questions independently. We included the first encounter from each adolescent and evaluated changes in adolescent self-reporting between pre- and post-intervention periods using interrupted time series analysis.
Results
Patients or caregivers completed 2,670 qualifying pre-visit screenings across 19 pre-intervention, 7 intervention, and 44 post-intervention weeks. Self-reporting by younger adolescents nearly doubled with a significant increase of 19.3 percentage points (CI 9.1-29.5) from the baseline 20.5%. Among older adolescents, the stable baseline rate of 53.6% increased by 9.2 absolute percentage points (CI -7.0-25.3). There were no significant pre- or post-intervention secular trends.
Conclusions
Two automated alerts directing clinic personnel and families to have adolescents self-report significantly and sustainably improved younger adolescent self-reporting on electronic patient-generated health data instruments
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