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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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At least 613 records · Page 34
All sourcesNASA NTRSDOE OSTI
DOE OSTI2018

Engage second wave ECP/CEED applications

The CEED co-design center aims to impact a wide range of ECP application teams through focused 1-to-1 and 1-to many interactions, facilitated by CEED application liaisons, ultimately targeted to provide easy-to-use discretization libraries for high-order FEM-based application simulations. The goal of this milestone was to extend our reach by identifying a second wave of ECP applications that can benefit from the efficient discretization algorithms and software developed in CEED. These applications were added to the list of the CEED first wave ECP applications (ExaSMR and MARBL), which continue to be main targets for our work. As part of the milestone, we also appointed liaisons on the CEED team that will be responsible for engaging each application, identifying its challenging discretization needs, and outlining a plan for interaction with CEED. Working with all CEED thrusts, the liaisons will be ultimately responsible for ensuring the adoption of CEED technologies in each application as well as for demonstrating their benefits. The selected second wave applications and CEED liaisons are: Urban - liaison Aleks Obabko (ANL), ExaWind - liaison Paul Fischer (UIUC), and ExaAM - liaison Tzanio Kolev (LLNL). In addition to details and results from these efforts, in this document we report on other project-wide activities performed in Q1 of FY19, including: engagements with performing scaling on V100 GPUs, collaboration with ECP/MPICH, participation in ECP/ST’s E4S release, the Laghos-2.0 release, papers, presentations, and other outreach efforts.

97 MATHEMATICS AND COMPUTING↗
DOE OSTI2023

Exact Maps to Second Order for Selected Elements in MAD-X Variables

This report presents calculations for exact maps to second order about an arbitrary orbit for certain elements: drifts, solenoids, and rotations about a transverse axis. These expressions were used in recent updates to MAD-X, and thus the phase space variables used are those of MAD-X. Formulas are given here for the final orbit and its first and second derivatives with respect to the incoming phase space coordinates for a drift, solenoid, and coordinate system rotations about transverse axes. I do not claim these results to be new: these expressions are well-known and are presented here only for reference. This document does not collect all maps that could be expressed exactly, in particular dipoles are omitted.

43 PARTICLE ACCELERATORS↗
DOE OSTI2023

Support for the Second MOSAiC Science Conference support (Final Report)

This is a final report for a conference support project. The US Department of Energy’s Atmospheric System Research Program provided funding support for the Second MOSAiC Science Conference. MOSAiC is the Multidisciplinary drifting Observatory for the Study of Arctic Climate, a yearlong, international expedition into the rapidly changing Arctic sea ice. The expedition collected measurements of the atmosphere, sea ice, and ocean to study coupled physical, chemical, and biological processes. The Second MOSAiC Science Conference provided an important opportunity to bring the MOSAiC-interested community together to discuss MOSAiC data, scientific analyses, synthesis, modeling activities, and more. Overall, the conference was a significant success and has motivated and facilitated a great deal of ongoing research. The support provide by this project was used along with support from other agencies to implement a participant support program that enabled participation in the conference by a diverse collection of researchers from many different countries and disciplines, 60% of whom were female. Most of these participants were Early Career Researchers. Participation by these researchers was vital to the overall success of the conference and has helped to build leadership and research skills for the participants that will serve both themselves and the broader scientific community in the future.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2024

Analysis of Second Target Station Target Segment Removal Dose Rates

This report documents the analysis of the dose rate fields in two configurations of the target system of the Second Target Station (STS) at the Spallation Neutron Source (SNS) at Oak Ridge National Laboratory (ORNL) in support of the remote handling target segment removal operation. The two configurations detailed in this report are both assuming 8 hours since beam was incident on the target. The first configuration assumes all shielding is in place just as it was during operation and allows for confirmation of hands-on maintenance capability of the target drive components. The second configuration assumes that a hatch in the target drive room ceiling has been opened to the high bay, the target segment removable core vessel shield block has been removed, and there is a direct line-of-sight to the target segment some 5 m below the target drive room elevation. Dose rate fields in both configurations are documented in this report along with details of the methods of computation. The dose rate fields included in this report are intended to support the engineering of remote handling special equipment and the planning of remote handing operations. The models and analysis detailed in this report are in support of the preliminary design of the STS and future analysis is needed to support the final design of the STS.

61 RADIATION PROTECTION AND DOSIMETRY↗
DOE OSTI2025

Second generation non-aqueous solvents (gen2nas) for co 2 capture from natural gas combined cycle plants

This final technical report submitted to DOE/NETL presents all the research activities performed during the Cooperative Agreement DE-FE0032218 entitled Second Generation Non-Aqueous Solvents (GEN2NAS) for CO 2 Capture from Natural Gas Combined Cycle Plants, which spanned from April 2023 through March 2025. In this project, Research Triangle Institute (RTI) International has developed the second-generation of its non-aqueous solvent (NAS), herein referred to as GEN2NAS, to remove carbon dioxide (CO 2 ) from natural-gas combined cycle (NGCC) flue gas. The technology aims to substantially reduce the cost of CO 2 capture while minimizing the environmental impacts through lower secondary emissions and wastewater generated from the CO 2 capture plant.

01 COAL, LIGNITE, AND PEAT↗
DOE OSTI2026

Second Order System Study

During my education in mathematics, engineering and physics, I learned transform pairs and their usage mechanics but I never remember seeing the derivations of the solutions to second order ordinary differential equations (ODE) and difference equations. A solution to a question posed in a potential funder meeting put me on a path to solving second order systems using the five principal Fourier based methods: Fourier transform (FT), Z-transform (ZT), discrete time Fourier transform (DTFT), discrete Fourier transform (DFT) and Laplace transform (LT).

42 ENGINEERING↗
DOE OSTI2016

Gas of 96 Planck cold clumps in the second quadrant

Ninety-six Planck cold dust clumps in the second quadrant were mapped with {sup 12}CO (1–0), {sup 13}CO (1–0), and C{sup 18}O (1–0) lines at the 13.7 m telescope of Purple Mountain Observatory. {sup 12}CO (1–0) and {sup 13}CO (1–0) emissions were detected for all 96 clumps, while C{sup 18}O (1–0) emissions were detected in 81 of them. Fifteen clumps have more than one velocity component. In the 115 mapped velocity components, 225 cores were obtained. We found that 23.1% of the cores have non-Gaussian profiles. We acquired the V {sub lsr}, FWHM, and T {sub A} of the lines. Distances, T {sub ex}, velocity dispersions, N{sub H{sub 2}}, and masses were also derived. Generally, turbulence may dominant the cores because σ{sub NT}/σ{sub Therm}>1 in almost all of the cores and Larson’s relationship is not apparent in our massive cores. Virial parameters are adopted to test the gravitational stability of cores and 51% of the cores are likely collapsing. The core mass function of the cores in the range 0–1 kpc suggests a low core-to-star conversional efficiency (0.62%). Only 14 of 225 cores (6.2%) have associated stellar objects at their centers, while the others are starless. The morphologies of clumps are mainly filamentary structures. Seven clumps may be located on an extension of the new spiral arm in the second quadrant while three are on the known outer arm.

79 ASTRONOMY AND ASTROPHYSICS↗
DOE OSTI2017

Nonlinear Effects in Three-minute Oscillations of the Solar Chromosphere. I. An Analytical Nonlinear Solution and Detection of the Second Harmonic

The vertical propagation of nonlinear acoustic waves in an isothermal atmosphere is considered. A new analytical solution that describes a finite-amplitude wave of an arbitrary wavelength is obtained. Although the short- and long-wavelength limits were previously considered separately, the new solution describes both limiting cases within a common framework and provides a straightforward way of interpolating between the two limits. Physical features of the nonlinear waves in the chromosphere are described, including the dispersive nature of low-frequency waves, the steepening of the wave profile, and the influence of the gravitational field on wavefront breaking and shock formation. The analytical results suggest that observations of three-minute oscillations in the solar chromosphere may reveal the basic nonlinear effect of oscillations with combination frequencies, superposed on the normal oscillations of the system. Explicit expressions for a second-harmonic signal and the ratio of its amplitude to the fundamental harmonic amplitude are derived. Observational evidence of the second harmonic, obtained with the Fast Imaging Solar Spectrograph, installed at the 1.6 m New Solar Telescope of the Big Bear Observatory, is presented. The presented data are based on the time variations of velocity determined from the Na i D{sub 2} and H α lines.

79 ASTRONOMY AND ASTROPHYSICS↗
DOE OSTI2017

Second-order Cosmological Perturbations Engendered by Point-like Masses

In the ΛCDM framework, presenting nonrelativistic matter inhomogeneities as discrete massive particles, we develop the second‐order cosmological perturbation theory. Our approach relies on the weak gravitational field limit. The derived equations for the second‐order scalar, vector, and tensor metric corrections are suitable at arbitrary distances, including regions with nonlinear contrasts of the matter density. We thoroughly verify fulfillment of all Einstein equations, as well as self‐consistency of order assignments. In addition, we achieve logical positive results in the Minkowski background limit. Feasible investigations of the cosmological back-reaction manifestations by means of relativistic simulations are also outlined.

79 ASTRONOMY AND ASTROPHYSICS↗
DOE OSTI2022

The R-Process Alliance: Abundance Universality among Some Elements at and between the First and Second R-Process Peaks*

Abstract We present new observational benchmarks of rapid neutron-capture process ( r -process) nucleosynthesis for elements at and between the first ( A ∼ 80) and second ( A ∼ 130) peaks. Our analysis is based on archival ultraviolet and optical spectroscopy of eight metal-poor stars with Se ( Z = 34) or Te ( Z = 52) detections, whose r -process enhancement varies by more than a factor of 30 (−0.22 ≤ [Eu/Fe] ≤ +1.32). We calculate ratios among the abundances of Se, Sr through Mo (38 ≤ Z ≤ 42), and Te. These benchmarks may offer a new empirical alternative to the predicted solar system r -process residual pattern. The Te abundances in these stars correlate more closely with the lighter r -process elements than the heavier ones, contradicting and superseding previous findings. The small star-to-star dispersion among the abundances of Se, Sr, Y, Zr, Nb, Mo, and Te (≤0.13 dex, or 26%) matches that observed among the abundances of the lanthanides and third r -process-peak elements. The concept of r -process universality that is recognized among the lanthanide and third-peak elements in r -process-enhanced stars may also apply to Se, Sr, Y, Zr, Nb, Mo, and Te, provided the overall abundances of the lighter r -process elements are scaled independently of the heavier ones. The abundance behavior of the elements Ru through Sn (44 ≤ Z ≤ 50) requires further study. Our results suggest that at least one relatively common source in the early Universe produced a consistent abundance pattern among some elements spanning the first and second r -process peaks.

74 ATOMIC AND MOLECULAR PHYSICS↗
DOE OSTI2018

The Fourteenth Data Release of the Sloan Digital Sky Survey: First Spectroscopic Data from the Extended Baryon Oscillation Spectroscopic Survey and from the Second Phase of the Apache Point Observatory Galactic Evolution Experiment

The fourth generation of the Sloan Digital Sky Survey (SDSS-IV) has been in operation since July 2014. This paper describes the second data release from this phase, and the fourteenth from SDSS overall (making this, Data Release Fourteen or DR14). This release makes public data taken by SDSS-IV in its rst two years of operation (July 2014{2016). Like all previous SDSS releases, DR14 is cumulative, including the most recent reductions and calibrations of all data taken by SDSS since the rst phase began operations in 2000. New in DR14 is the rst public release of data from the extended Baryon Oscillation Sky Survey (eBOSS); the rst data from the second phase of the Apache Point Observatory (APO) Galactic Evolution Experiment (APOGEE-2), including stellar parameter estimates from an innovative data driven machine learning algorithm known as The Cannon; and almost twice as many data cubes from the Mapping Nearby Galaxies at APO (MaNGA) survey as were in the previous release (N = 2812 in total). This paper describes the location and format of the publicly available data from SDSS-IV surveys. We provide references to the important technical papers describing how these data have been taken (both targeting and observation details) and processed for scienti c use. The SDSS website (www.sdss.org) has been updated for this release, and provides links to data downloads, as well as tutorials and examples of data use. SDSS-IV is planning to continue to collect astronomical data until 2020.

79 ASTRONOMY AND ASTROPHYSICS↗
DOE OSTI2019

Swift-XRT Follow-up of Gravitational-wave Triggers in the Second Advanced LIGO/Virgo Observing Run

The Neil Gehrels Swift Observatory carried out prompt searches for gravitational-wave (GW) events detected by the LIGO/Virgo Collaboration (LVC) during the second observing run ("O2"). Swift performed extensive tiling of eight LVC triggers, two of which had very low false-alarm rates (GW170814 and the epochal GW170817), indicating a high confidence of being astrophysical in origin; the latter was the first GW event to have an electromagnetic counterpart detected. In this paper we describe the follow-up performed during O2 and the results of our searches. No GW electromagnetic counterparts were detected; this result is expected, as GW170817 remained the only astrophysical event containing at least one neutron star after LVC's later retraction of some events. A number of X-ray sources were detected, with the majority of identified sources being active galactic nuclei. We discuss the detection rate of transient X-ray sources and their implications in the O2 tiling searches. Finally, we describe the lessons learned during O2 and how these are being used to improve the Swift follow-up of GW events. In particular, we simulate a population of gamma-ray burst afterglows to evaluate our source ranking system's ability to differentiate them from unrelated and uncataloged X-ray sources. We find that ≈60%–70% of afterglows whose jets are oriented toward Earth will be given high rank (i.e., "interesting" designation) by the completion of our second follow-up phase (assuming that their location in the sky was observed), but that this fraction can be increased to nearly 100% by performing a third follow-up observation of sources exhibiting fading behavior.

79 ASTRONOMY AND ASTROPHYSICS↗
DOE OSTI2018

The Geoengineering Model Intercomparison Project- Introduction to the Second Special Issue

The Geoengineering Model Intercomparison Project (GeoMIP) has just concluded its second special issue, which this article introduces. Here we discuss the history of GeoMIP, what was learned in the first special issue, why a second special issue was needed, the additional knowledge that was provided in that issue, and some next steps for GeoMIP and the field of geoengineering research. We focus on response and uncertainty across climate models, questions for which GeoMIP is particularly well suited.

42 ENGINEERING↗
NASA NTRS1961

Results of the Second U.S. Manned Suborbital Space Flight, July 21, 1961

This document presents the results of the second United States manned suborbital space flight. The data and flight description presented form a continuation of the information provided at an open conference held under the auspices of the National Aeronautics and Space Administration, in cooperation with the National Institutes of Health and the National Academy of Sciences, at the U.S. Department of State Auditorium on June 6, 1961. The papers presented herein generally parallel the presentations of the first report and were prepared by the personnel of the NASA Manned Spacecraft Center in collaboration with personnel from other government agencies, participating industry, and universities. The second successful manned suborbital space flight on July 21, 1961, in which Astronaut Virgil I. Grissom was the pilot was another step in the progressive research, development, and training program leading to the study of man's capabilities in a space environment during manned orbital flight. Data and operational experiences gained from this flight were in agreement with and supplemented the knowledge obtained from the first suborbital flight of May 5, 1961, piloted by Astronaut Alan B. Shepard, Jr. The two recent manned suborbital flights, coupled with the unmanned research and development flights, have provided valuable engineering nd scientific data on which the program can progress. The successful active participation of the pilots, in much the same way as in the development and testing of high performance aircraft, has. greatly increased our confidence in giving man a significant role in future space flight activities. It is the purpose of this report to continue the practice of providing data to the scientific community interested in activities of this nature. Brief descriptions are presented of the Project Mercury spacecraft and flight plan. Papers are provided which parallel the presentations of data published for the first suborbital space flight. Additional information is given relating to the operational aspects of the medical support activities for the two manned suborbital space flights.

Source record↗
NASA NTRS1965

Second Symposium on Protection Against Radiations in Space

All space vehicles will be exposed to natural charged particle radiation fields. The effects and possible problems imposed by such radiations are of great concern to those actively engaged in the exploration of space. Materials and components, which may be damaged by the radiation, frequently can be replaced by more radiation resistant items; however, replacement systems are not always possible or practical and, hence, protective measures in the form of shielding must be employed. (One of the more radiation-sensitive systems to be flown in space is man himself.) Many groups are engaged in research on the attenuation and penetration of high-energy space radiation and on the development of methods for the design of shielding which affords protection against the radiation. The purpose of the Second Symposium on Protection Against Radiations in Space, like that of the First, was to bring these groups together to exchange information and share ideas. These proceedings are the written record of the Second Symposium. Invited papers covering the space radiation environment, radiobiological effects, and radiation effects on materials and components comprised the first three sessions. By defining the radiation problems in space and providing for the proper assessment of the radiation effects and shielding requirements, these papers helped to establish the necessary background for the shielding papers which followed in the fourth session.

radiation protection↗
NASA NTRS1968

A second-generation /high-speed/ maximum power tracker for space applications.

During the past few years, considerable effort has been exerted by both industry and government to improve the performance of space power systems. One of the significant advances has been the development of practical Maximum Power-Point Tracking (MPPT) systems. This paper presents the background and evolution of a second-generation (high-speed) MPPT system capable of operation with solar arrays with rapidly fluctuating parameters due to mission operation (e.g., spin-stabilized spacecraft). An experimental model of the high-speed MPPT system has been constructed and tested. Results from these tests are presented herein. The second-generation MPPT system provides a means of efficient power conditioning that can result in significant increases over conventional systems in space-power system capability. Of additional importance is the applicability of the basic technology to all types of spacecraft, and the wide variety of power-system configurations with which the high-speed MPPT system concept may be used.

Clement A. Berard, Jr.↗