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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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In this paper, a procedure is described for finding these encounter times using Lambert's theorem and Tisserand's criterion to identify pairs of transfer orbits between the launch planet and intermediate planet and between the intermediate planet and target planet.
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An innovative new telerobotic inspection system called STAR has been developed to asist engineers in the visual and thermal analysis fo flight hardware being tested in a simulated space environment. This paper describes the architecture of the STAR mechanical and control systems and discusses some uses of STAR to date.
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Unexpected energy increases during Earth flybys of both the Galileo and Near Earth Asteroid Rendzvous (NEAR) spacecraft have drawn evidence of spacecraft trajectory modeling errors, an unknown perturbing force or failure of Newtonian gravity.
This paper will further investigate the possible resources of these anomalous delta-V's beyond the work of Kallemeyn.
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The Salinas Valley region of California’s Central Coast is a majorU.S. vegetable producer. Lettuce is a leading commodity, grown on about 100,000 acres with annual value near $1.4B (2022 Monterey County Ag Report). Vegetables crops in the area aretypically well watered and fertilized in pursuit of commercial yield and quality standards. Information on irrigation application efficiency, meanwhile, can enhance waterresource sustainability and mitigate impacts of nitrate infiltrationon groundwater quality. The Crop Consumptive Use Fraction (CCUF), previously recommended by the California Department of Water Resources, is a metric that expresses evapotranspiration (ET) of applied water relative to total applied water. More recently under Assembly Bill 1668 addressing water conservation and drought planning, the metric can be used to help quantify application efficiency to support preparation of agricultural water management plans in the state. This study will report CCUF evaluations from several commercial lettuce plantings in the Salinas Valley during the 2022 dry season (late spring-early fall). The evaluations were derived from satellite-based observations of cropET from the OpenETcloud application, and applied water monitored by in-line flowmetersand supplemented by grower reports of irrigation system runtime. The study will also compare observed (satellite-based) ET with modeled ET from the CropManage irrigationand nutrient management decision-support system operated by Cooperative Extension. Additional study in cool-season vegetables is ongoing in 2023.
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Simulated automated adaptive countdown demonstration test - prelaunch testing
Planetary quarantine program studies involving mathematical models for predicting spacecraft contamination, and clean room design
Blood pressure reprogramming adapter separates the two components of a blood pressure signal, a dc pressure signal and an ac Korotkoff sounds signal, so that the Korotkoff sounds are recorded on one channel as received while the dc pressure signal is converted to FM and recorded on a second channel.
Apparatus for generation of infrared and far infrared new laser lines