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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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Tesseral harmonics of coordinates using Baker- Nunn data and geopotential and dynamical procedures, noting iterative cycle for correction determination
Corrections to station coordinates and nonzonal coefficients of geogravitational potential from Baker-Nunn observations by combined dynamical and geometrical method
Lie series solution of equations resulting from separation of Helmholtz equation in special coordinate systems
This paper introduces a simple decentralized protocol that enables seperate planners to coordinate shared tasks and resolve conflicts over shared and private resources.
This paper describes and evaluates three methods for coordinating multiple agents.
This presentation will discuss the operational status update of the Constellation Coordination System (CCS) Release 7.0 and the development status of CCS Release 7.1.
This will be presented at the Earth Science Constellation Mission Operations Working Group meeting June 13-15, 2017, to discuss Operatioins Coordination Plan Status.
This presentation will be given at the Mission Operations Working Group meeting June 13-15, 2017 to discuss the Constellation Coordination System status.
This will be presented at the Earth Science Constellation Mission Operations Working Group meeting to discuss Operations Coordination Plan Status.
This presentation will discuss the updates made to the Constellation Coordination System (CCS) over the past year in releases 2018.2 and 2018.3. These updates will be highlighted during the live demonstration of the system during the presentation. The future of CCS will then be discussed. The presentation will end with discussion and feedback from the audience.
Doppler Orbitography and Radiopositioning Integrated on Satellite (DORIS)is a tracking technique based on a one-way ground to space Doppler link.For Low Earth Orbit (LEO) satellites, DORIS shows a robust capability interms of data coverage and availability, due to a wide and well-distributedground network, where data are made available by the International DorisService (IDS). However, systematic errors remain in the DORIS data, suchas instabilities of the on-board clock due to radiation encountered in space,which limit the accurate determination of station positions.The DORIS on-board clock frequency stability is degraded by the increased radiation found in the region of the South Atlantic Anomaly (SAA)and has been shown to degrade station position estimation. This paper in-troduces a new model correction to the DORIS data for the frequency ofthe Jason-2 Ultra Stable Oscillator (USO), derived from the Time Transferby Laser Link (T2L2) experiment (Belli and Exertier, 2018). We show thata multi-satellite DORIS solution including this T2L2-corrected data appliedto the frequency modelling for The DORIS data, improves the estimationof station coordinates. We show the tie residuals with respect to collocatedGPS stations are improved by several millimeters. We also demonstratethat the 117-day (Jason-2) draconitic signal in the geophysical parametersis reduced, implying that the origin of this signal is not just solar radiationpressure mis-modeling, but also radiation-induced clock perturbations onthe Jason-2 DORIS Ultra-Stable-Oscillator (USO). Finally we demonstratethrough comparisons with the International Earth Rotations and ReferenceSystems Service (IERS) C04 series for Earth Orientation Parameters (EOP),that the estimation of EOP is improved in both a Jason-2 DORIS-only anda multi-satellite DORIS solution for EOP.
This paper presents a study of the TOPEX/Poseidon and Jason-1 coordinated navigation effort performed by the TOPEX/Poseidon navigation team.
This paper compares and contrasts several coordination schemes for a system that continuously plans to control collections of rovers or spacecraft using collective mission goals instead of goals or command sequences for each spacecraft.
Crown Consulting Inc. has been tasked by NASA to elicit information from operators, vehicle manufacturers, and service suppliers on the expected xTM-ATC coordination. For this presentation, first, an introduction for the task and the process is discussed. The second part of the presentation will go through the results which are broken up into the participant company types that we interviewed to elicit feedback on the issues / barriers associated with the introduction of new vehicles and their system (called xTM) into the National Airspace System. The company types are HAPS (Balloons/HALE), sUAS, Large UAS, UAM, Supersonics, and Supporting Technology Providers.
The determination of relationships between climate variables and the identification of the most significant associations between them in various geographic regions is an important aspect of climate model evaluation. The EDEN visual analytics toolkit has been developed to aid such analysis by facilitating the assessment of multiple variables with respect to the amount of variability that can be attributed to specific other variables. EDEN harnesses the parallel coordinates visualization technique and is augmented with graphical indicators of key descriptive statistics. A case study is presented in which the focus on the Harvard Forest site (42.5378N Lat, 72.1715W Lon) and the Community Land Model Version 4 (CLM4) is evaluated. It is shown that model variables such as land water runoff are more sensitive to a particular set of environmental variables than a suite of other inputs in the 88 variable analysis conducted. The approach presented here allows climate-domain scientists to focus on the most important variables in the model evaluations.
An internal brochure for Clean Cities coordinators that covers key points about the program and mission, with facts about alternative fuels and technologies.
This talk will present NREL's work on developing predictive analytics that enables the optimal coordination of all the available resources in distribution systems to achieve the control objectives of system operators. Two projects will be presented. One focuses on developing short-term state forecasting-based optimal voltage regulation in distribution systems; and the other one focuses on actively engaging electricity consumers to benefit distribution system operations.
This presentation provides a high-level overview of the opportunistic hybrid communications systems for distributed photovoltaic coordination.