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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 307 records · Page 17
All sourcesNASA NTRSDOE OSTI
NASA NTRS1995

Active noise control using noise source having adaptive resonant frequency tuning through stiffness variation

A noise source for an aircraft engine active noise cancellation system in which the resonant frequency of a noise radiating element is tuned to permit noise cancellation over a wide range of frequencies. The resonant frequency of the noise radiating element is tuned by a plurality of force transmitting mechanisms which contact the noise radiating element. Each one of the force transmitting mechanisms includes an expandable element and a spring in contact with the noise radiating element so that excitation of the element varies the spring force applied to the noise radiating element. The elements are actuated by a controller which receives input of a signal proportional to displacement of the noise radiating element and a signal corresponding to the blade passage frequency of the engine's fan. In response, the controller determines a control signal which is sent to the elements and causes the spring force applied to the noise radiating element to be varied. The force transmitting mechanisms can be arranged to either produce bending or linear stiffness variations in the noise radiating element.

Pla, Frederic G.↗
DOE OSTI2012

Packaging and Transportation Support at LANL CTMA 2012

Operations Support Packaging and Transportation (OS-PT) supports LANL in various functions. Some highlights of the past year have been with the work relating to environmental remediation, type B packaging, non-DOT compliant transfers, and special permit training. The TA-21 remediation project was part of the ARRA funding that LANL received. The $212 million in funding was used to demolish 24 buildings at TA-21, excavate the lab's oldest waste disposal site, and install 16 groundwater monitoring wells. The project was completed ahead of schedule and under budget. More than 300 tons of metal was recycled and all the soil excavated from MDA-B was replaced with clean fill. OS-PT supported this projected by transporting more than 7 million pounds of waste to TA-54 Area G with an addendum to their TSD. Because of the public access on the transfer route, Los Alamos County restricted the transfer to happen from 2:00 AM to 4:00 AM. OS-PT conducted 8 transfers in support of this project. Some concerns included the contaminated trailers at receipt facilities when transferring filled Super Sacks. Future Super Sacks were over packed into new IP-2 Super Sacks before shipping. OS-PT is also supporting the remediation of TA-54 Area G. LANL has an agreement with the State of New Mexico to remove all TRU waste currently stored above ground from at Area G. OS-PT supports this initiative with transfers of TRU waste under LANL's TSD and support of TRU shipments to WIPP. Another project supported by our organization is gas cylinder/dewar recycling and remediation. We are focusing on reducing risk associated with unneeded gasses at LANL. To minimized excessive ordering, to save money and time, and to minimize hazards OS-PT is supporting a gas recycling program. This program will allow programmatic organization across LANL to share unused/unneeded gasses. Instead of old dewars being disposed of, OS-PT has began identifying these dewars and sending them for refurbishment. To date, this effort has saved LANL $450K and estimated saving for future efforts will be more than $1.5 million. Some Projects that are happening here at LANL are offsite source recovery, weapon component transfers, and isotope science production. There are specific packages that help support these projects for the shipment of related materials. OS-PT provides support to these packages to ensure they are and will be available to continue this support. The Areva 435-B Overpack will help the Offsite Source Recovery Project recover high activity gamma sources from various locations across the globe. The Safety Analysis for Packaging is scheduled for initial completion June of 2012. The DPP-1 package is designed to replace the Model FL, which was designed by Rocky Flats and began service in 1990. LANL has collaborated on package design with LLNL, Pantex, Y-12, and KCP. LANL is supporting LLNL on component fixture development. Testing to 10 CFR 71 is to be completed in the Fall of 2012 and scheduled for NA-174 approval in 2014. The SAFESHIELD package helps supports LANL's Isotope production projects. This package can transfer highly irradiated materials from LANL's accelerator to material processing facilities. LANL worked to renew the SAFESHEILD's Certification for 5 more years.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
NASA NTRS2023

Automated Global-Scale Detection and Characterization of Anthropogenic Activity using Multi-Source Satellite-Based Remote Sensing Imagery

Satellite-based remote sensing imagery is an effective means for detecting objects and structures in support of many applications. However, detecting the spatial and temporal bounds of a specific activity in satellite imagery is inherently more complex and research in this area is nascent. One reason for this is that describing an activity implies defining both spatial and temporal bounds and while activity is inherently continuous in nature, the geospatial (imagery) time series for any particular swath of ground provided by satellite imagery is relatively sparse and discrete in comparison. The IARPA Space-Based Machine Automated Recognition Technique (SMART)1 program is the first large-scale research program to target advancing the state of the art for automatically detecting, characterizing, and monitoring large-scale anthropogenic activity in global, multispectral satellite imagery. The program has two primary research objectives: 1) the “harmonization” of multiple imagery sources and 2) automated reasoning at scale to detect, characterize, and monitor activities of interest. This paper provides details on the goals, dataset, metrics, and lessons learned of the IARPA SMART program. By releasing the annotated dataset, the program aims to foster additional research in this area by the community at large.

Hirsh R Goldberg↗
DOE OSTI2019

Offsite Source Recovery Program; High Activity Beta Gamma Removal, Transport and Disposition - 19663

The Department of Energy's (DOE) National Nuclear Security Administration's (NNSA) Office of Radiological Security's (ORS) Off-Site Source Recovery Program (OSRP) has been tasked with the removal and disposition of radioactive sealed sources in the interest of national security and public health and safety. It is the mission of the program to recover radioactive sources to prevent them from falling into the hands of individuals who would use this material for malicious intent. OSRP is a collaborative effort involving Los Alamos National Laboratory (LANL), Idaho National Laboratory (INL), and Lawrence Livermore National Laboratory (LLNL). At the inception of the program, Pu-239 was the only isotope acceptable for recovery. As a wider security scope developed, OSRP expanded its mission to include the recovery of other sources that posed a potential risk to national security, health, and safety. Starting in 2004, OSRP began recovering cesium and cobalt devices, largely from medical, research, and industrial facilities. These disused higher-activity devices present a burden to licensees in terms of security, and demand for OSRP's assistance in removing them has been high. Today, OSRP removes around 40 high-activity devices per year in support of domestic demand as well as ORS's Cesium Irradiator Replacement Project (CIRP). This represents an average of over 50,000 Ci of Cs-137 and Co-60 removed from the private sector each year for permanent disposition. A major component of this effort is the use of the proper shipping container to transport the devices. As a way to increase transportation capabilities ORS has developed two new Type B containers. The most recently completed of these containers, the 435-B, is currently certified to transport Gammators and Gammacell-1000, -3000, and -40 irradiators in an overpack configuration. This provides greater capacity and flexibility to safely and effectively transport these devices, for which acceptable shipping configurations had been previously limited. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
NASA NTRS2008

The Radio Luminosity Function and Galaxy Evolution in the Coma Cluster

We investigate the radio luminosity function and radio source population for two fields within the Coma cluster of galaxies, with the fields centered on the cluster core and southwest infall region and each covering about half a square degree. Using VLA data with a typical rms sensitivity of 28 (mu)Jy per 4.4" beam, we identify 249 radio sources with optical counterparts brighter than r = 22 (equivalent to M(sub r) = -13 for cluster member galaxies). Comprehensive optical spectroscopy identifies 38 of these as members of the Coma cluster, evenly split between sources powered by an active nucleus and sources powered by active star formation. The radio-detected star-forming galaxies are restricted to radio luminosities between about 10(exp 21) and 10(exp 22) W/Hz, an interesting result given that star formation dominates field radio luminosity functions below about 10(exp 23) W/Hz. The majority of the radio-detected star-forming galaxies have characteristics of starbursts, including high specific star formation rates and optical spectra with strong emission lines. In conjunction with prior studies on post-starburst galaxies within the Coma cluster, this is consistent with a picture in which late-type galaxies entering Coma undergo a starburst prior to a rapid cessation of star formation. Optically bright elliptical galaxies (Mr less than or equals -20.5) make the largest contribution to the radio luminosity function at both the high (> approx. 3x10(exp 22) W/Hz) and low (< approx. 10(exp 21) W/Hz) ends. Through a stacking analysis of these optically-bright ellipticals we find that they continue to harbor radio sources down to luminosities as faint as 3x10(exp 19) W/Hz. However, contrary to published results for the Virgo cluster we find no evidence for the existence of a population of optically faint (M(sub r) approx. equals -14) dwarf ellipticals hosting strong radio AGN.

Miller, Neal A.↗
DOE OSTI2012

Efficiency of TTAC's ORTEC IDM

ORNL's Technical Testing and Analysis Center (TTAC) acquired a High Purity Germanium Detector (HPGe) from ORTEC - a variant called an Interchangeable Detection Module (IDM). This detector has excellent energy resolution as well as high intrinsic efficiency. The purpose of this report is to detail the determination of the efficiency curve of the IDM, so future measurements can quantify the (otherwise unknown) activity of sources. Without such a curve, the activity cannot be directly reported by use of the IDM alone - a separate device such as an ion chamber would be required. This builds upon the capability of TTAC. The method for determining the energy-dependent intrinsic efficiency is laid-out in this report. It's noteworthy that this basic technique can be applied to any spectroscopic radiation detector, independent of the specific type (e.g. NaI, CzT, ClYC).

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗
NASA NTRS1987

The atmospheres of M dwarfs: Observations

After presenting global properties of M dwarfs, the principal diagnostic of activity phenomena occurring in their atmosphere from the geometrical, energetic, and temporal points of view is stressed. Observations of sunspots, plages, flares, and activity cycles are presented. The major sources of activity are discussed with particular emphasis on the generation, intensification, and measurements of stellar magnetic fields.

Rodono, Marcello↗
NASA NTRS2009

Multiwavelength Challenges in the Fermi Era

The gamma-ray surveys of the sky by AGILE and the Fermi Gamma-ray Space Telescope offer both opportunities and challenges for multi wavelength and multimessenger studies. Gamma-ray bursts, pulsars, binary sources, flaring Active Galactic Nuclei, and Galactic transient sources are all phenomena that can best be studied with a wide variety of instruments simultaneously or contemporaneously. From the gamma-ray side, a principal challenge is the latency from the time of an astrophysical event to the recognition of this event in the data. Obtaining quick and complete multiwavelength coverage of gamma-ray sources of interest can be difficult both in terms of logistics and in terms of generating scientific interest.

Thompson, D. J.↗
NASA NTRS2010

Multiwavelength Challenges in the Fermi Era

The gamma-ray surveys of the sky by AGILE and the Fermi Gamma-ray Space Telescope offer both opportunities and challenges for multiwavelength and multi-messenger studies. Gamma-ray bursts, pulsars, binary sources, flaring Active Galactic Nuclei, and Galactic transient sources are all phenomena that can best be studied with a wide variety of instruments simultaneously or contemporaneously. From the gamma-ray side, a principal challenge is the latency from the time of an astrophysical event to the recognition of this event in the data. Obtaining quick and complete multiwavelength coverage of gamma-ray sources of interest can be difficult both in terms of logistics and in terms of generating scientific interest.

Thompson, D. J.↗
NASA NTRS2011

The Helioseismic and Magnetic Imager (HMI) Investigation for the Solar Dynamics Observatory (SDO)

The Helioseismic and Magnetic Imager (HMI) instrument and investigation as a part of the NASA Solar Dynamics Observatory (SDO) is designed to study convection-zone dynamics and the solar dynamo, the origin and evolution of sunspots, active regions, and complexes of activity, the sources and drivers of solar magnetic activity and disturbances, links between the internal processes and dynamics of the corona and heliosphere, and precursors of solar disturbances for space-weather forecasts. A brief overview of the instrument, investigation objectives, and standard data products is presented.

Helioseismology↗
NASA NTRS2013

The First Fermi-LAT Catalog of Sources Above 10 GeV

We present a catalog of gamma-ray sources at energies above 10 GeV based on data from the Large Area Telescope (LAT) accumulated during the first 3 yr of the Fermi Gamma-ray Space Telescope mission. The first Fermi-LAT catalog of >10 GeV sources (1FHL) has 514 sources. For each source we present location, spectrum, a measure of variability, and associations with cataloged sources at other wavelengths. We found that 449 (87%) could be associated with known sources, of which 393 (76% of the 1FHL sources) are active galactic nuclei. Of the 27 sources associated with known pulsars, we find 20 (12) to have significant pulsations in the range >10 GeV (>25 GeV). In this work we also report that, at energies above 10 GeV, unresolved sources account for 27% +/- 8% of the isotropic γ -ray background, while the unresolved Galactic population contributes only at the few percent level to the Galactic diffuse background. We also highlight the subset of the 1FHL sources that are best candidates for detection at energies above 50-100 GeV with current and future ground-based γ -ray observatories.

catalogs↗
NASA NTRSDate not supplied

Updates in Developing a Prototype Science Pipeline and Full-Volume, Global Hyperspectral Synthetic Data Sets for NASA’s Earth System Observatory’s Upcoming Surface, Biology and Geology Mission

The Surface Biology and Geology (SBG) mission recently passed mission confirmation review and has entered phase A – design and development. SBG will acquire high resolution solar-reflected spectroscopy and thermal infrared observations at a data rate of ~2.5 TB/day and generate products at ~40 TB/day. Given that the per-day volume is greater than NASA’s total extant airborne hyperspectral data collection, collecting, processing, disseminating, and exploiting the SBG data present new challenges. To meet these challenges, we have developed a prototype science pipeline and a full-volume global hyperspectral synthetic data set to help prepare for SBG’s flight (see poster GC42D-0730). Our science pipeline is based on the science processing technology developed for NASA’s Kepler and TESS planet-hunting missions. The pipeline infrastructure, Ziggy, provides a scalable architecture for robust, repeatable, and replicable science and application products that can be run on a range of systems from a laptop to the cloud or a supercomputer. Ziggy is compliant with NASA Procedural Requirement (NPR) 7150.2C, is at a technical readiness level (TRL) of 7 and has been released to github.com/nasa/ziggy. We integrated Ziggy with EO-1/Hyperion workflows to build a prototype pipeline and ingested the 17-year mission archive that provides globally sampled visible through shortwave infrared spectra that are representative of SBG data types and volumes. We fully implemented the first stage and processed the entire 55 TB Hyperion data set from the raw data (Level 0) to top-of-the-atmosphere radiance (Level 1R). We are currently evaluating the ISOFIT atmospheric correction module to convert the L1R data to surface reflectance (Level 2) before reprocessing the full data set to L2. Crosschecks are being performed with RadCalNet as well as with coincident observations by AVIRIS. We are also investigating modern methods for georectifying the Hyperion scenes. Finally, we describe an analysis of the cost to conduct forward processing and reprocessing campaigns for SBG on HECC with dedicated compute and storage resources using the resurrected Hyperion pipeline as a proxy for full-volume SBG data. The analysis demonstrates that SBG L0 data can be processed to L2 on HECC with full reprocessing campaigns every two years for ~$2.6M over a 7-year lifespan. Moreover, 69% of the system capacity would be available for other activities, possibly enabling future open-source science activities, including algorithm development, L3+ processing, .etc.

ESD↗
DOE OSTI2016

Management of Radioactive Wastes (RWs) and Disused Sealed Radioactive Sources (DSRSs) in Bangladesh: Recent Activities and Challenges Ahead - 16039

The use of radioactive sources in different applications and practices gives rise to various types of RWs that may be detrimental to human health and the environment if not properly managed. Since early sixties of the last century, radioisotopes have found diversified and incremental uses in Bangladesh in the field of medicine, industry, agriculture, food irradiation, research and education and so on. Currently, the country is operating nuclear facilities like 3 MW TRIGA research reactor (TRR), radioisotope production (RIP) facility as well as particle accelerators. Recently, the country has decided to establish nuclear power plants in order to cope with its increasing demand of electric power. The first nuclear power plant is anticipated to come into operation by 2021-2022. Consequently, a notable amount and range of RWs including DSRSs are being expected to be generated from these diversified applications of radioactive materials in near future. Bangladesh has limited facilities and capabilities to manage the RWs which are being currently generated from the conventional activities and practices with radioactive materials. However, the country is also working to improve its necessary capabilities and infrastructures for the management of RWs expected to be generated from both conventional and nuclear activities in future in a comprehensive, integrated and safer manner, ensuring that no undue burden is imposed on present and future generations and on the environment. This paper illustrates the current activities as well as its future plans on the management of RWs and DSRSs in the country. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2024

The importance of delayed neutron precursors in gamma dose calculations for activated primary heat exchanger components in the Molten Salt Breeder Reactor

The Molten Salt Reactor (MSR) Multiphysics Applications technical area in the Nuclear Energy Advanced Modeling and Simulation program has supported the development of 3D Monte Carlo models of the Molten Salt Breeder Reactor (MSBR) over the last couple of years. This MSBR model was previously run with the Shift Monte Carlo code to perform radiation shielding calculations in the reactor cell area. The MSBR is a 2250 MWth (1000 MWe) liquid-fueled molten salt reactor design developed at Oak Ridge National Laboratory in the 1970s. Determining the source terms from activated primary heat exchanger (HX) components is important because delayed and prompt neutron fluxes incident on these components affect the dose rate in the primary HX maintenance areas. This information can be used in the development of remote handling procedures required during shutdown for maintenance. A methodology has been developed and is proposed in this paper to quantify the activated source term from the primary HX components as a result of the movement of the delayed neutron precursors in flowing primary fuel salt through the primary HXs in the MSBR. The goal of this research is to evaluate the gamma dose rates in the maintenance hatches above the primary HX using the activated HX source terms. The study showed that the gamma dose rates are approximately two orders of magnitudes higher when accounting for the neutron activation from the movement of delayed neutron precursors through the HXs than when flowing fuel is not considered. Thus, the movement of delayed neutron precursors must be taken into account for accurately predicting the neutron activation of primary loop components.

22 GENERAL STUDIES OF NUCLEAR REACTORS↗
NASA NTRSDate not supplied

Numerical Implementation of Source Terms to Evaluate Active Porosity Control using a Transpiration Cooled Thermal Protection System

Transpiration cooling has renewed interest of study as a renewable system of thermal protection for atmospheric entry systems. The presence of coolant within the void space of a porous material changes its effective porosity and theorized to lend the external heatshield as a potential means of porous surface control. Effective porosity is explored in two forms: saturation of void space where exiting coolant creates ‘blowing’ over the surface, and partial evacuation of the void space where withdrawal of the coolant creates ‘suction’ on the surface. Thus this study evaluates using transpiration cooling as a as means of active aerodynamic control. The feasibility of the system is evaluated numerically using Reynolds-averaged Navier Stokes based computational fluid dynamics for the aerodynamic assessments by coding source terms of transpiration cooling products at a heat shield surface boundary at the wind side shoulder, creating an asymmetric scheme. Study results show induced moments about the pitch axis incurred following the source terms of a cooling fluid at a near-shoulder location on the heat shield. Lift and drag saw increasing modulation with increase in mass flux rate. Pitch moment was altered a total of 388 N-m between lowest and highest ‘suction’ rates and changed 194 N-m maximum between ‘blowing’ rates.

transpiration cooling↗
DOE OSTI2014

Detection of Petawatt Laser-Induced Muon Source for Rapid High-Z Material Detection

A proof-of-concept investigation of a rapid detection system for shielded high-Z material using a petawatt laser-based muon source is presented. Unlike cosmic-ray muons, a laser-induced muon beam has unique characteristics that can be exploited for use in a rapid detection system. These characteristics include: (1) a near-point source of muons, (2) well-characterized muon energies, and (3) directionality of the beam. A detector system is being developed that combines multiple muon detection technologies to characterize an active muon source. This detection system and the associated data acquisition and analysis techniques are designed to search for deflections of the muon beam as it passes through high-Z materials. Additionally, the ability of the system to differentiate muons from the expected secondary particles, such as high-energy gammas and electrons, is being explored. The detector system’s ability to differentiate muons from other particles, show muon angular distribution, and measured muon flux will be discussed.

scintillation detector, petawatt laser-based muon ↗
DOE OSTI2015

Adsorption of basic Red 46 using sea mango (Cerbera odollam) based activated carbon

Sea mango or Cerbera Odollam is another source of carbonaceous material that can be found abundantly in Malaysia. In this research, it is used as a new agricultural source of activated carbon. Sea mango activated carbon was prepared by chemical activation using potassium hydroxide (KOH). The sea mango was soaked in KOH at impregnation ratio of 1:1 and followed by carbonization at temperature of 600°C for 1 hour. The sample was then characterized using Scanning Electron Microscope (SEM) for surface morphology, while Brunauer-Emmett-Teller (BET) was used to study the surface area. The result shown that sea mango activated carbon (SMAC) developed new pores on its surface and the BET surface area measured was 451.87 m{sup 2}/g. The SMAC performance was then tested for the removal of Basic Red 46 in batch process. The removal of Basic Red 46 (50 mg/L, natural pH, 0.1 g SMAC) was more than 99% in 15 minutes where it reached equilibrium in 30 minutes.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2014

Source localization of brain activity using helium-free interferometer

To detect extremely small magnetic fields generated by the human brain, currently all commercial magnetoencephalography (MEG) systems are equipped with low-temperature (low-T{sub c}) superconducting quantum interference device (SQUID) sensors that use liquid helium for cooling. The limited and increasingly expensive supply of helium, which has seen dramatic price increases recently, has become a real problem for such systems and the situation shows no signs of abating. MEG research in the long run is now endangered. In this study, we report a MEG source localization utilizing a single, highly sensitive SQUID cooled with liquid nitrogen only. Our findings confirm that localization of neuromagnetic activity is indeed possible using high-T{sub c} SQUIDs. We believe that our findings secure the future of this exquisitely sensitive technique and have major implications for brain research and the developments of cost-effective multi-channel, high-T{sub c} SQUID-based MEG systems.

71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗