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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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All sourcesNASA NTRSDOE OSTI
DOE OSTI2024

Waste management strategies for military-generated waste in the United States

Sustainable and energy efficient municipal solid waste (MSW) management is vital for the health and performance of deployed soldiers, as they play an important role in the safety and dignity of a country. As the United States targets net-zero carbon-free emission goals, research and development are essential to surpassing current practices for management of MSW at military installations, both at home and abroad. To achieve this, it is important to act upon and implement the policies and instructions set by government agencies such as the Environmental Protection Agency (EPA), the Department of Energy (DOE), and the Department of Defense (DoD). Understanding the composition of waste and disposal methods that are in use at military installations is a crucial step to success. Here, the authors show this through analyzed data from trusted sources, such as government agencies, reports, magazines, journals, and other publications on MSW management techniques. By defining these challenges, possible solutions can be better understood for improved management of MSW at military installations in the United States. Finally, an integrated approach with deployable units capable of waste-to-energy technology using waste reduction, diversion, and recycling strategies shows to be an effective pathway for MSW conversion into energy and other useful products.

09 BIOMASS FUELS↗
DOE OSTI2022

Analysis of Integrated Vapor Transport Biases

Abstract High-fidelity analyses and forecasts of integrated vapor transport (VT) are central to the study of Earth’s hydrological cycle as well as high-impact phenomena such as monsoons and atmospheric rivers. The impact of the in-line analysis correction-based additive inflation (ACAI) on IVT biases and forecast errors is examined within the Navy Earth System Prediction Capability (Navy ESPC) global coupled system. The ACAI technique uses atmospheric analysis corrections from the data assimilation system to approximate model bias and as a representation of stochastic model error to simultaneously reduce systematic and random errors and improve ensemble performance. ACAI reduces the global average magnitude of the 7- and 14-day IVT bias by 16%–17% during Northern Hemisphere summer, reaching 70% reductions in some tropical regions. The global average IVT bias reduction is similar to the bias reduction for low-level wind speed bias and considerably smaller than the bias reduction in total precipitable water. The localized regions where ACAI increases IVT bias occur where the control IVT biases change sign and structure with increasing forecast lead time, such as the South Asian monsoon region. Substituting analyzed wind or moisture fields for the forecast fields when calculating the forecast IVT confirms that, on average, wind errors dominate the IVT error calculation in the tropics, although wind and moisture error contributions are comparable in the extratropics. The existence of regions where using either analyzed winds or analyzed moisture increases IVT bias or mean absolute error reveals areas with compensating errors.

Reynolds, Carolyn A.↗
NASA NTRS2000

[Protein turnover during and after extended space flight]

A 15N-glycine tracer technique was used to study protein turnover in four Russian cosmonauts and two U.S. astronauts who had spent long time aboard the Russian orbital station MIR. As was shown, in space flight protein synthesis falls by 46% on the average, which substantially exceeds estimations made on the basis of data about bed-rested human subjects. Reduction in protein synthesis during space flight is connected with the negative energy balance; therefore, it appears imperative to keep balance between energy intake (foodstuffs) and expenditure by cosmonauts on long-term mission.

manned↗
DOE OSTI2021

Noise reduction in X-ray photon correlation spectroscopy with convolutional neural networks encoder–decoder models

Abstract Like other experimental techniques, X-ray photon correlation spectroscopy is subject to various kinds of noise. Random and correlated fluctuations and heterogeneities can be present in a two-time correlation function and obscure the information about the intrinsic dynamics of a sample. Simultaneously addressing the disparate origins of noise in the experimental data is challenging. We propose a computational approach for improving the signal-to-noise ratio in two-time correlation functions that is based on convolutional neural network encoder–decoder (CNN-ED) models. Such models extract features from an image via convolutional layers, project them to a low dimensional space and then reconstruct a clean image from this reduced representation via transposed convolutional layers. Not only are ED models a general tool for random noise removal, but their application to low signal-to-noise data can enhance the data’s quantitative usage since they are able to learn the functional form of the signal. We demonstrate that the CNN-ED models trained on real-world experimental data help to effectively extract equilibrium dynamics’ parameters from two-time correlation functions, containing statistical noise and dynamic heterogeneities. Strategies for optimizing the models’ performance and their applicability limits are discussed.

36 MATERIALS SCIENCE↗
DOE OSTI2018

A complex approach to assessing porous structure of structured ceramics obtained by SPS technique

Highlights: • A complex approach to microstructural analysis of nanostructured SPS ceramics was presented. • A bunch of gas, intrusion and microscopic methods were applied for open/closed porosity determination in nanoceramics. • Kinetic TPR analysis for structural changes in nanoceramic was carried out. • 3D pore visualization for nanoceramics was provided via SEM/FIB tomography • Porosity calculations were performed via BET, BJH, t-plot, Washburn equation, FEI Avizo 9.1 software results. - Abstract: Spark plasma sintering (SPS) is a highly prospective technology providing rapid consolidation of nano-disperse compositions into structured ceramics with complex structural organization. Characterizing pore structure of such systems remains a challenge due to different types, size and shape of the pores as well as structural defects occurring in the material, thus requiring special methods to quantify certain porosity type. The paper presents a complex approach to studying structure of SPS hematite-based structured ceramics. The method involves a number of gas, intrusion and electron microscopy probing techniques to characterize open and closed pores in the ceramics bulk. Low temperature nitrogen sorption has been implemented to estimate open micro- and mesoporosity in the size range 0.7–50 nm using BET, BJH and t-plot methods to process experimental data. Additionally, structural peculiarities of consolidated structured ceramics have been studied using temperature-programmed reduction (TPR) with the kinetic analysis of the results being carried out. Volume of macropores sized above 50 nm has been measured with mercury intrusion. Closed pores and structural defects have been quantified with SEM and FIB/SEM tomography. By comparing experimental and estimated results we have shown that addressing all porosity types provides a highly precise structural characterization of the material.

77 NANOSCIENCE AND NANOTECHNOLOGY↗
DOE OSTI2025

Bayesian inference of anisotropic 2D small-angle scattering from sparse measurement

Here, we present a Bayesian inference framework for reconstructing anisotropic two-dimensional small-angle scattering (2D SAS) patterns from sparse, noisy, or partially missing data. The method combines a symmetry-aware angular basis with radial Gaussian process priors to enable accurate, training-free interpolation and denoising. Computational benchmarks demonstrate reliable recovery of both isotropic and high-order anisotropic features under severe data reduction. Experimental validations on stretched polymers, sheared wormlike micelles, and carbon fibers show improved fidelity and resolution compared to raw measurements, achieving comparable accuracy with up to 50-fold fewer detected neutrons. This approach enables quantitative structural analysis under low-flux, time-limited, or single-shot conditions, extending the applicability of 2D SAS techniques to compact neutron sources and mechanically driven soft matter systems undergoing transient structural changes.

Tung, Chi-Huan [Oak Ridge National Laboratory (ORN↗
NASA NTRS1977

Impurity concentrations and surface charge densities on the heavily doped face of a silicon solar cell

Increased solar cell efficiencies are attained by reduction of surface recombination and variation of impurity concentration profiles at the n(+) surface of silicon solar cells. Diagnostic techniques are employed to evaluate the effects of specific materials preparation methodologies on surface and near surface concentrations. It is demonstrated that the MOS C-V method, when combined with a bulk measurement technique, yields more complete concentration data than are obtainable by either method alone. Specifically, new solar cell MOS C-V measurements are combined with bulk concentrations obtained by a successive layer removal technique utilizing measurements of sheet resistivity and Hall coefficient.

Weinberg, I.↗
NASA NTRS1978

Predetection telemetry analog recording and playback for Pioneer Venus 1978

Prediction telemetry recording and playback capability was implemented in the DSN to meet PV-78 mission requirements. Test data, along with theoretical considerations, gives assurance that the data degradation commitment of 1.5 db will be met, and it is anticipated that in actual performance the design goal of 1.0 db will be met. The major technical problems requiring solution were elimination of image in the OLR and the reduction of analog recorder instabilities. These were solved through the use of single-sideband mixing techniques and the use of newer generation analog recorders.

Kent, S. S.↗
NASA NTRS1985

Application of imaging to the atmospheric Cherenkov technique

Turver and Weekes proposed using a system of phototubes in the focal plane of a large reflector to give an air Cherenkov camera for gamma ray astronomy. Preliminary results with a 19 element camera have been reported previously. In 1983 the camera was increased to 37 pixels; it has now been routinely operated for two years. A brief physical description of the camera, its mode of operation, and the data reduction procedures are presented. The Monte Carlo simultations on which these are based on also reviewed.

Cawley, M. F.↗
NASA NTRS2012

In-Situ Nondestructive Evaluation of Kevlar(Registered Trademark)and Carbon Fiber Reinforced Composite Micromechanics for Improved Composite Overwrapped Pressure Vessel Health Monitoring

NASA has been faced with recertification and life extension issues for epoxy-impregnated Kevlar 49 (K/Ep) and carbon (C/Ep) composite overwrapped pressure vessels (COPVs) used in various systems on the Space Shuttle and International Space Station, respectively. Each COPV has varying criticality, damage and repair histories, time at pressure, and pressure cycles. COPVs are of particular concern due to the insidious and catastrophic burst-before-leak failure mode caused by stress rupture (SR) of the composite overwrap. SR life has been defined [1] as the minimum time during which the composite maintains structural integrity considering the combined effects of stress level(s), time at stress level(s), and associated environment. SR has none of the features of predictability associated with metal pressure vessels, such as crack geometry, growth rate and size, or other features that lend themselves to nondestructive evaluation (NDE). In essence, the variability or surprise factor associated with SR cannot be eliminated. C/Ep COPVs are also susceptible to impact damage that can lead to reduced burst pressure even when the amount of damage to the COPV is below the visual detection threshold [2], thus necessitating implementation of a mechanical damage control plan [1]. Last, COPVs can also fail prematurely due to material or design noncompliance. In each case (SR, impact or noncompliance), out-of-family behavior is expected leading to a higher probability of failure at a given stress, hence, greater uncertainty in performance. For these reasons, NASA has been actively engaged in research to develop NDE methods that can be used during post-manufacture qualification, in-service inspection, and in-situ structural health monitoring. Acoustic emission (AE) is one of the more promising NDE techniques for detecting and monitoring, in real-time, the strain energy release and corresponding stress-wave propagation produced by actively growing flaws and defects in composite materials [3,4,5,6,7,8]. To gain further insight into the mechanisms responsible for composite rupture, broadband modal acoustic emission analysis was used. Also, since AE data reduction proved to be very time consuming, specialized data reduction software was written to automate the process.

Waller, Jess↗
NASA NTRS2012

Top-down Estimate of Dust Emissions Through Integration of MODIS and MISR Aerosol Retrievals With the Geos-chem Adjoint Model

Predicting the influences of dust on atmospheric composition, climate, and human health requires accurate knowledge of dust emissions, but large uncertainties persist in quantifying mineral sources. This study presents a new method for combined use of satellite-measured radiances and inverse modeling to spatially constrain the amount and location of dust emissions. The technique is illustrated with a case study in May 2008; the dust emissions in Taklimakan and Gobi deserts are spatially optimized using the GEOSChem chemical transport model and its adjoint constrained by aerosol optical depth (AOD) that are derived over the downwind dark-surface region in China from MODIS (Moderate Resolution Imaging Spectroradiometer) reflectance with the aerosol single scattering properties consistent with GEOS-chem. The adjoint inverse modeling yields an overall 51% decrease in prior dust emissions estimated by GEOS-Chem over the Taklimakan-Gobi area, with more significant reductions south of the Gobi Desert. The model simulation with optimized dust emissions shows much better agreement with independent observations from MISR (Multi-angle Imaging SpectroRadiometer) AOD and MODIS Deep Blue AOD over the dust source region and surface PM10 concentrations. The technique of this study can be applied to global multi-sensor remote sensing data for constraining dust emissions at various temporal and spatial scales, and hence improving the quantification of dust effects on climate, air quality, and human health.

MODIS aerosol retrievals↗
NASA NTRSDate not supplied

Particle and Trace Gas Emissions Indices Measured During the 2021 Boeing ecoDemonstrator Emissions Ground Test

We present particle and trace gas emissions indices sampled on the ground at 30 meters behind the CFM LEAP-1B engines of the 2021 Boeing ecoDemonstrator, an Alaska Airlines 737-9 aircraft. Testing was carried out at Boeing Field in Seattle, WA, USA in Fall of 2021. Four different fuels were investigated including a 100% sustainable aviation fuel (SAF), a petroleum-based Jet A fuel, and two SAF blends. Total and non-volatile particle number concentrations were measured with a pair of condensation particle counters with one operating behind a custom-built thermal denuder heated to 350 degrees Celsius. Similarly, total and non-volatile particle number size distributions were measured with a pair of Scanning Mobility Particle Sizers (SMPSs). Non-volatile particle mass was estimated from particle light absorption techniques using an assumed mass absorption coefficient, while particle chemical speciation was measured by an Soot Particle Aerosol Mass Spectrometer (SP-AMS). A detailed list of instruments is given on the project website [1]. Overall, the results are consistent with expectations based on ICAO Emissions Databank certification data for the LEAP-1B with a stark reduction in non-volatile particle number and mass observed for the higher thrust conditions when the combustor was staged. The production of volatile particles under these conditions as well as experimental considerations related to background subtraction methods will be discussed. References: [1] Boeing ecoDemonstrator Science and Engineering Team (2022). 2021 Boeing ecoDemonstrator Emissions Ground Test Dataset

Richard H Moore↗
NASA NTRSDate not supplied

Particle and Trace Gas Emissions Indices Measured During the 2021 Boeing ecoDemonstrator Emissions Ground Test

We present particle and trace gas emissions indices sampled on the ground at 30 meters behind the CFM LEAP-1B engines of the Boeing ecoDemonstrator 737-9 aircraft. Testing was carried out at Boeing Field in Seattle, WA, USA in Fall of 2021. Four different fuels were investigated including a 100% sustainable aviation fuel (SAF), a petroleum-based Jet A fuel, and two SAF blends. Total and non-volatile particle number concentrations were measured with a pair of condensation particle counters with one operating behind a custom-built thermal denuder heated to 350 degrees Celsius. Similarly, total and non-volatile particle number size distributions were measured with a pair of Scanning Mobility Particle Sizers (SMPSs). Non-volatile particle mass was estimated from particle light absorption techniques using an assumed mass absorption coefficient, while particle chemical speciation was measured by an Soot Particle Aerosol Mass Spectrometer (SP-AMS). A detailed list of instruments is given on the project website [1]. Overall, the results are consistent with expectations based on ICAO Emissions Databank certification data for the LEAP-1B with a stark reduction in non-volatile particle number and mass observed for the higher thrust conditions when the combustor was staged. The production of volatile particles under these conditions as well as experimental considerations related to background subtraction methods will be discussed.

Benjamin A. Nault↗
DOE OSTI2019

DRILLING OPTIMIZATION OF A CANEY SHALE WELL USING OFFSET WELL DRILLING DATA

Cost reduction can be achieved by utilizing drilling simulators to efficiently optimize new wells to be drilled using available adjacent or offset well drilling data. Different approaches involving simulators that use inverted rate of penetration (ROP) models have been implemented to help improve the drilling performance of wells primarily within the Caney shale. A complete simulation and optimization technique is presented herein which utilizes drilling data from a nearby or offset well (Garrett well) to create an optimized drilling program for a new well to be drilled (Gallaway well).

02 PETROLEUM↗
DOE OSTI2023

Classical and quantum compression for edge computing: the ubiquitous data dimensionality reduction

Edge computing aims to address the challenges associated with communicating and transferring large amounts of data generated remotely to a data center in a timely and efficient manner. A central pillar of edge computing is local (i.e., at- or near-source) data processing capability so that data transfer to a data center for processing can be minimized. Data compression at the edge is therefore a natural component of edge workflows. Here we present a survey of data compression algorithms with a focus on edge computing. Not all compression algorithms can accommodate the data type heterogeneity, tight processing and communication time constraints, or energy efficiency requirement characteristics of edge computing. We discuss specific examples of compression algorithms that are being explored in the context of edge computing. We end our review with a brief survey of emerging quantum compression techniques that are of importance in quantum information processing, including the proposed concept of quantum edge computing.

97 MATHEMATICS AND COMPUTING↗
NASA NTRS1995

Effect of pressure on a burning solid in low-gravity

Venting, or depressurization, has been discussed as a possible technique for extinguishing fires on aircraft and spacecraft. Fire suppression plans for the International Space Station Alpha (ISSA) discuss the use of depressurization as a method for extinguishing fires. In the case of an uncontrollable fire, the affected compartment would be vented from an initial pressure of 1.0 atm (14.7 psia) to a final pressure 0.33 atm (4.8 psia) within 10 minutes. However, the lack of low pressure flammability data for solid materials in a low-gravity environment presents an uncertainty for the use of the venting technique. There are also transient effects that need to be considered. It is possible that the flows induced by the venting could intensify the fire. This occurred during flammability tests conducted on board Skylab. In addition, the extinction pressure could be a function of the depressurization rate. Studies conducted with solid propellants have shown that if the pressure is reduced quickly enough, the pressure at extinction will be greater than the steady-state extinction limit. This project, which was started in 1992, is examining both the quasi steady-state and transient effects of pressure reduction on a burning solid in low-gravity. This research will provide low-g extinguishment data upon which policies and practices can be formulated for fire safety in orbiting spacecraft.

Goldmeer, Jeffrey S.↗
NASA NTRS1975

Spacelab user interaction

The results of the third and final phase of a study undertaken to define means of optimizing the Spacelab experiment data system by interactively manipulating the flow of data were presented. A number of payload applicable interactive techniques and an integrated interaction system for each of two possible payloads are described. These interaction systems have been functionally defined and are accompanied with block diagrams, hardware specifications, software sizing and speed requirements, operational procedures and cost/benefits analysis data for both onboard and ground based system elements. It is shown that accrued benefits are attributable to a reduction in data processing costs obtained by, generally, a considerable reduction in the quantity of data that might otherwise be generated without interaction. One other additional anticipated benefit includes the increased scientific value obtained by the quicker return of all useful data.

Source record↗
NASA NTRS1997

Measurements of Ice Nucleating Aerosols in the Upper Troposphere and Lower Stratosphere

Our major accomplishments during Year 1 were: Development of aerosol and crystal collection techniques. Development of single-particle chemical characterization techniques. Modification of system design for DC-8 and initial testing. Our major accomplishments during Year 2 were: Completion of system design and proof-of-concept experiments. Participation in SUCCESS mission. Reporting of theoretical and laboratory findings in the scientific literature. Reporting of initial SUCCESS results at scientific meetings. Our major accomplishments during Year 3 were: Data reduction and submission of all SUCCESS data to the archive. Participation in SUCCESS data comparison workshops. Reporting of SUCCESS results at the AEAP Meeting. Organization of CN counter intercomparison workshop. Preparation of three manuscripts submitted to the GRL SUCCESS Special Issue.

Kreidenweis, S. M.↗