Constellation Coordination System (CCS) Status
This presentation will be given at the Mission Operations Working Group meeting June 13-15, 2017 to discuss the Constellation Coordination System status.
Constellation coordination system↗
SEARCH · Engineering Papers
Results for “coordinates”
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.
Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.
Operations Coordination Plan Status
This will be presented at the Earth Science Constellation Mission Operations Working Group meeting to discuss Operations Coordination Plan Status.
statu↗
Constellation Coordination System (CCS) 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.
constellation coordination system↗
Impact of Jason-2/T2L2 Ultra-Stable-Oscillator Frequency Model on DORIS stations coordinates and Earth Orientation Parameters
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.
DORIS↗
TOPEX/POSEIDON and JASON-1 coordinated navigation
This paper presents a study of the TOPEX/Poseidon and Jason-1 coordinated navigation effort performed by the TOPEX/Poseidon navigation team.
coordinated↗
From Rovers to Orbiters: Continuous Task-Distribution-Based Coordination
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.
Rovers↗
xTM - ATM Coordination - Knowledge Elicitation Results: xTM Operational Domain
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.
xTM-ATM coordination↗
Clean Cities Coordinator Talking Points; Clean Cities, U.S. Department of Energy
An internal brochure for Clean Cities coordinators that covers key points about the program and mission, with facts about alternative fuels and technologies.
33 ADVANCED PROPULSION SYSTEMS↗
Predictive Analytics for Coordinated Optimization in Distribution Systems
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.
24 POWER TRANSMISSION AND DISTRIBUTION↗
Opportunistic Hybrid Communications Systems for Distributed PV Coordination
This presentation provides a high-level overview of the opportunistic hybrid communications systems for distributed photovoltaic coordination.
24 POWER TRANSMISSION AND DISTRIBUTION↗
Coordinative Voltage Control Strategy with Multiple Resources for Distribution Systems of High PV Penetration: Preprint
This paper presents an optimal voltage control methodology with coordination among different voltage-regulating resources, including controllable loads, distributed energy resources such as energy storage and photovoltaics (PV), and utility voltage-regulating devices such as voltage regulators and capacitors. The proposed methodology could effectively tackle the overvoltage and voltage regulation device distortion problems brought by high penetrations of PV to improve grid operation reliability. A voltage-load sensitivity matrix and voltage-regulator sensitivity matrix are used to deploy the resources along the feeder to achieve the control objectives. Mixed-integer nonlinear programming is used to solve the formulated optimization control problem. The methodology has been tested on the IEEE 123-feeder test system, and the results demonstrate that the proposed approach could actively tackle the voltage problem brought about by high penetrations of PV and improve the reliability of distribution system operation.
14 SOLAR ENERGY↗
Coordinated Ramping Product and Regulation Reserve Procurements Using Probabilistic Solar Power Forecasts
This presentation provides an overview of coordinated ramping product and regulation reserve procurements using probabilistic solar power forecasts.
14 SOLAR ENERGY↗
IAEA coordinated research project on thermal-hydraulics of Supercritical Water-Cooled Reactors (SCWRs)
The Supercritical Water-Cooled Reactor (SCWR) is an innovative water-cooled reactor concept, which uses supercritical pressure water as reactor coolant. It has been attracting interest of many researchers in various countries mainly due to its benefits of high thermal efficiency and simple primary systems, resulting in low capital cost. The IAEA started in 2008 a Coordinated Research Project (CRP) on Thermal-Hydraulics of SCWRs as a forum to foster the exchange of technical information and international collaboration in research and development. This paper summarizes the activities and current status of the CRP, as well as major progress achieved to date. At present, 15 institutions closely collaborate in several tasks. Some organizations have been conducting thermal-hydraulics experiments and analysing the data, and others have been participating in code-to-test and/or code-to-code benchmark exercises. The expected outputs of the CRP are also discussed. Finally, the paper introduces several IAEA activities relating to or arising from the CRP. (authors)
21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS↗
Preserving spherical symmetry in axisymmetric coordinates for diffusion problems
Persevering symmetric solutions, even in the under-converged limit, is important to the robustness of production simulation codes. We explore the symmetry preservation in both a continuous nodal and a mixed finite element method. In their standard formulation, neither method preserves spherical solution symmetry in axisymmetric (RZ) coordinates. We propose two methods, one for each family of finite elements, that recover spherical symmetry for low-order finite elements on linear or curvilinear meshes. This is a first step toward understanding achieving symmetry for higher-order elements. (authors)
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗
The IAEA coordinated research project on modular HTGR safety design: status and outlook - 18608
The IAEA Coordinated Research Project (CRP) on Modular High Temperature Gas-cooled Reactor (HTGR) Safety Design started in December 2014 and is now in its second year of implementation. The project investigates and makes proposals on safety design criteria by not only considering the existing water cooled reactors safety requirements for nuclear power plant design but also making use of past and current experience of HTGR licensing in the IAEA member states. Two approaches are being followed to establish the criteria. The first is to develop and apply a safety design process to specific reactor de-signs. The second is to use the existing IAEA specific safety requirements for designs based on water cooled reactor technology and then through expert judgment and review propose changes that is needed to make it applicable to HTGRs. The detailed project content and a description of modular HTGRs and its safety features are given. This informs the comments made on the applicability of the existing requirements and the examples of newly pro-posed HTGR specific safety requirements under development. (authors)
21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS↗
Vapor–Fed Electrolyzers for Carbon Dioxide Reduction Using Tandem Electrocatalysts: Cuprous Oxide Coupled with Nickel–Coordinated Nitrogen–Doped Carbon
We report ethylene is particularly attractive due to its major importance as a feedstock for various applications including the polymer industry. As such, catalyst and electrolyzer developments are crucial to achieve industrially relevant ethylene production and efficiency levels. In this work, a tandem electrocatalyst composed of copper nanocubes and nickel-coordinated nitrogen-doped carbon (NiNC) is presented, which is integrated into gas diffusion electrodes (GDEs) for direct conversion of vapor-fed CO 2 into ethylene. Evaluation of tandem GDEs in the vapor-fed flow electrolyzer shows significantly increased ethylene selectivity in terms of faradaic efficiency and C 2 H 4 /CO ratio compared to a non-tandem copper GDE. The enhancements are attributed to the increased local CO availability near the copper surface via effective CO 2 to CO conversion on neighboring NiNC. The experimental results are validated by 3D resolved continuum simulations, which show increased flux of higher-order prod-ucts with the added CO flux from NiNC. The practical viability of Cu/NiNC catalyst is further evaluated in a membrane electrode assembly electrolyzer, achieving 40% FE toward ethylene at 150 mA cm -2 and 3.2 V. These find-ings highlight the high selectivity and formation rate of ethylene achieved by successful device integration of the Cu/NiNC catalyst, demonstrating the potential for implementation in large-scale sustainable CO 2 electrolyzers.
36 MATERIALS SCIENCE↗
Crosslinked Poly(tetrahydrofuran) as a Loosely Coordinating Polymer Electrolyte
Abstract Solid polymer electrolytes (SPEs) promise to improve the safety and performance of lithium ion batteries (LIBs). However, the low ionic conductivity and transference number of conventional poly(ethylene oxide) (PEO)‐based SPEs preclude their widespread implementation. Herein, crosslinked poly(tetrahydrofuran) (xPTHF) is introduced as a promising polymer matrix for “beyond PEO” SPEs. The crosslinking procedure creates thermally stable, mechanically robust membranes for use in LIBs. Molecular dynamics and density functional theory (DFT) simulations accompanied by 7 Li NMR measurements show that the lower spatial concentration of oxygen atoms in the xPTHF backbone leads to loosened O–Li + coordination. This weakened interaction enhances ion transport; xPTHF has a high lithium transference number of 0.53 and higher lithium conductivity than a xPEO SPE of the same length at room temperature. It is demonstrated that organic additives further weaken the O–Li + interaction, enabling room temperature ionic conductivity of 1.2 × 10 −4 S cm −1 with 18 wt% N,N ‐dimethylformamide in xPTHF. In a solid‐state LIB application, neat xPTHF SPEs cycle with near theoretical capacity for 100 cycles at 70 °C, with rate capability up to 1 C. The plasticized xPTHF SPEs operate at room temperature while maintaining respectable rate capability and capacity. The novel PTHF system demonstrated here represents an exciting platform for future studies involving SPEs.
Mackanic, David G.↗
Effects of penta‐coordinated Al 3+ sites and Ni defective sites on Ni/ Al 2 O 3 for CO methanation
Abstract Engineering sophisticated structure of Al 2 O 3 and controlling the structure of counterpart metal active sites remain challenges to achieve a high catalytic‐performance in heterogeneous catalysis. Herein, we present a confinement strategy to stabilize homogeneous Ni by penta‐coordinated Al 3+ anchoring sites in Al 2 O 3 . This approach is involved in using a metal–organic framework as host to load Ni 2+ ions, by the aim of producing a confined Ni/Al 2 O 3 catalyst after a standard calcination. Metal–support interaction between Ni and Al 2 O 3 was tailored to be medium to avoid the formation of inactive NiAl 2 O 4 , which favors the generation of more available Ni active sites accessible to the reactants. The resultant Ni/Al 2 O 3 exhibited superior catalytic performance in comparison with the control Ni/Al 2 O 3 in CO methanation owing to the presence of defective sites on sufficient Ni 0 surface. Furthermore, the presence of oxygen vacancies on Al 2 O 3 and hydrogen spillover contributed toward excellent coke resistance properties in the reaction.
Engineering↗