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At least 505 records · Page 28

Future Trends in Logistics and Sustainment

Airship Industry Study: In 2015, NASA Ames Research Center completed a study of the overall airship industry. The project called for a report that describes airship concepts proposed or projects initiated in recent years, airship performance or capability targets, and the missions these activities were addressing. The resulting report details the principal technical features of these airships, the proposed value/advantages of the features, notional concepts of operation, and challenges associated with such vehicles. The study investigated the current status and near-term prospects of these airship development activities, whether they are active or, if curtailed, the circumstances and possible reasons for that conclusion, including technical, business, or other mitigating factors. This presentation provides highlights of the Airship Industry Study investigations, findings, and recommendations. UAS Carrier Concept: The advantages of utilizing an airship as an airborne carrier for support and deployment of Unmanned Aircraft Systems (UAS) are examined. Whether as a stand-alone platform or in concert with conventional aircraft, the airship UAS carrier provides a number of compelling benefits for both military and civilian missions. As a mobile base it can remain operational despite political fallout that may render ground or ocean based UAS sites unavailable. It offers the psychological impact of a power projection tool that has few geographical limits, and holds promise as a new method for cost-saving intelligence gathering. It is also adaptable for civilian variants for supporting: emergency response, security/surveillance, delivery of medical/food supplies, as well as commercial package delivery to metropolitan and remote communities.

Hochstetler, Ron↗

Unravelling the Components of a Multi-Thermal Coronal Loop Using Magnetohydrodynamic Seismology

Coronal loops, constituting the basic building blocks of the active Sun, serve as primary targets to help understand the mechanisms responsible for maintaining multi-million Kelvin temperatures in the solar and stellar coronae. Despite significant advances in observations and theory, our knowledge on the fundamental properties of these structures is limited. Here, we present unprecedented observations of accelerating slow magnetoacoustic waves along a coronal loop that show differential propagation speeds in two distinct temperature channels, revealing the multi-stranded and multithermal nature of the loop. Utilizing the observed speeds and employing nonlinear force free magnetic field extrapolations, we derive the actual temperature variation along the loop in both channels, and thus are able to resolve two individual components of the multithermal loop for the first time. The obtained positive temperature gradients indicate uniform heating along the loop, rather than isolated foot point heating.

Prasad, S. Krishna↗

Airship Industry Study

In April, 2015 NASA Ames Research Center conducted a study of the airship industry. The project called for a report that would describe airship concepts proposed or projects initiated, airship performance or capability targets, and the missions these activities were addressing. It would detail the principal technical features of these airships; the proposed value/advantages of the features, notional concepts of operation, and challenges associated with the vehicles. Also investigated would be the current status and near-term prospects of these airship development activities, whether they are active or, if curtailed the circumstances and possible reasons for that conclusion including technical, business, or other mitigating factors. For the most active programs an assessment would be conducted to identify the resources or activities required for airships to advance to series construction and operational deployment. The study would also identify impediments to these developments and deployments, with recommendations provided to address existing issues in the airship industry today.

Hochstetler, Ron↗

L’Ralph Integration and Testing

This paper describes the plans, flows, key facilities, components and equipment necessary to fully integrate, functionally test, qualify and calibrate the L’Ralph instrument on the Lucy observatory. Lucy is currently in the final design and fabrication phase (phase C) of mission development. It is scheduled to launch out of Cape Canaveral, Florida, in October 2021. Lucy will be the first space mission to study the Trojan asteroids associated with Jupiter, that are thought to be remnants of the primordial material that formed the outer planets. Lucy will fly by and carry out remote sensing on six different Trojan asteroids. The mission takes its name from the fossilized human ancestor (called “Lucy” by her discoverers) whose skeleton provided unique insight into humanity's evolution. Likewise, the Lucy mission will revolutionize our knowledge of planetary origins and the formation of the solar system. L’Ralph is one of the instruments on Lucy and it is provided by the NASA Goddard Space Flight Center (GSFC). L’Ralph is a combined multi-band visible imager (the Multi-spectral Visible Imaging Camera, MVIC, 0.4-0.85 microns) and wedge-filter infrared spectrometer (Linear Etalon Imaging Spectral Array, LEISA, 1-3.6 microns). LEISA will allow the team to look for the absorption lines that serve as the fingerprints for different silicates, ices and organics that likely will be on the surface of the Trojan asteroids. MVIC will take color images of the Trojan asteroid targets, and help determine how active they are. This paper will focus on the Integration and Test (I&T) activities for L’Ralph while it is at the NASA GSFC. L’Ralph has two assemblies, the telescope detector assembly (TDA) and main electronics box (MEB). The TDA is a single telescope feeding two focal planes, MVIC and LEISA. L’Ralph integration consists of assembly and alignment of the telescope, electronics box integration, thermal systems integration and the final assembly and testing. This I&T phase will be followed by the L’Ralph calibration and characterization, environmental tests which include electromagnetic interference (EMI)/electromagnetic compatibility (EMC), vibration with sine sweep, acoustics, shock, thermal balance, thermal vacuum, mass properties and center of gravity determination. This paper will briefly discuss L’Ralph shipment and delivery to the spacecraft vendor for observatory level I&T as well as some launch preparation activities.

Spaceflight Instruments↗

Preliminary Design of a Distributed Facesheet Acoustic Liner for Broadband Acoustic Attenuation

The purpose of this study is to investigate the acoustic performance of a liner with a distributed facesheet and a uniform depth core for broadband attenuation. The distributed facesheet is comprised of a cluster of three distinct cell resonators of varying hole diameter and porosity replicated over the active liner treatment area. A target frequency range of 1000 to 2000 Hz and an attenuation metric of 10 dB are chosen. An optimizer is used to determine the optimal facesheet designs for flow conditions of Mach 0.0 and Mach 0.3. The samples are tested in the Grazing Flow Impedance Tube at NASA Langley Research Center. The two liners are shown to achieve at least 10 dB attenuation over frequency ranges of 700 and 400 Hz, respectively, when tested at their respective designed flow speeds. This study demonstrate that a distributed facesheet with a uniform depth core can be successfully used to achieve broadband sound absorption.

acoustic liners↗

Low profile pressure disconnect device for lithium ion batteries

Casings for lithium ion batteries are provided that include a container or assembly that defines a base, side walls and a top or lid, and a vent structure associated with the container or assembly. A flame arrestor may be positioned in proximity to the vent structure. The lithium ion battery may also include a pressure disconnect device associated with the casing. The pressure disconnect device may include a deflectable dome-based activation mechanism, and the deflectable dome-based activation mechanism may be configured and dimensioned to prevent burn through, e.g., by increasing the mass of the dome-based activation mechanism, adding material (e.g., foil) to the dome-based activation mechanism, and combinations thereof. Burn through may also be avoided, at least in part, based on the speed at which the dome-based activation mechanism responds at a target trigger pressure.

25 ENERGY STORAGE↗

Optical Control of Dopamine D2-like Receptors with Cell-Specific Fast-Relaxing Photoswitches

Dopamine D2-like receptors (D2R, D3R, and D4R) control diverse physiological and behavioral functions and are important targets for the treatment of a variety of neuropsychiatric disorders. Their complex distribution and activation kinetics in the brain make it difficult to target specific receptor populations with sufficient precision. We describe a new toolkit of light-activatable, fast-relaxing, covalently taggable chemical photoswitches that fully activate, partially activate, or block D2-like receptors. This technology combines the spatiotemporal precision of a photoswitchable ligand (P) with cell type and spatial specificity of a genetically encoded membrane anchoring protein (M) to which the P tethers. These tools set the stage for targeting endogenous D2-like receptor signaling with molecular, cellular, and spatiotemporal precision using only one wavelength of light.

59 BASIC BIOLOGICAL SCIENCES↗

Genome-wide fetalization of enhancer architecture in heart disease

Heart disease is associated with re-expression of key transcription factors normally active only during prenatal development of the heart. However, the impact of this reactivation on the regulatory landscape in heart disease is unclear. Here, we use RNA-seq and ChIP-seq targeting a histone modification associated with active transcriptional enhancers to generate genome-wide enhancer maps from left ventricle tissue from up to 26 healthy controls, 18 individuals with idiopathic dilated cardiomyopathy (DCM), and five fetal hearts. Healthy individuals have a highly reproducible epigenomic landscape, consisting of more than 33,000 predicted heart enhancers. In contrast, we observe reproducible disease-associated changes in activity at 6,850 predicted heart enhancers. Combined analysis of adult and fetal samples reveals that the heart disease epigenome and transcriptome both acquire fetal-like characteristics, with 3,400 individual enhancers sharing fetal regulatory properties. We also provide a comprehensive data resource (http://heart.lbl.gov) for the mechanistic exploration of DCM etiology.

60 APPLIED LIFE SCIENCES↗

Head-Up Auditory Displays for Traffic Collision Avoidance System Advisories: A Preliminary Investigation

The advantage of a head-up auditory display was evaluated in a preliminary experiment designed to measure and compare the acquisition time for capturing visual targets under two auditory conditions: standard one-earpiece presentation and two-earpiece three-dimensional (3D) audio presentation. Twelve commercial airline crews were tested under full mission simulation conditions at the NASA-Ames Man-Vehicle Systems Research Facility advanced concepts flight simulator. Scenario software generated visual targets corresponding to aircraft that would activate a traffic collision avoidance system (TCAS) aural advisory; the spatial auditory position was linked to the visual position with 3D audio presentation. Results showed that crew members using a 3D auditory display acquired targets approximately 2.2 s faster than did crew members who used one-earpiece head- sets, but there was no significant difference in the number of targets acquired.

Begault, Durand R.↗

Beyond conventional batteries: a review on semi-solid and redox targeting flow batteries-LiFePO{sub 4} as a case study.

Clean and sustainable energy is becoming increasingly crucial to tackle the current energy crisis. However, the intermittent nature of renewable energy sources presents a challenge for their effective implementation. Redox flow batteries (RFBs) have emerged as a promising solution to this problem, as they can help enhance the stability of grid networks and promote the use of renewable energy sources. RFBs are highly modular and scalable systems that can be customized to meet the power and energy requirements of different renewable energy plants. Moreover, they offer several advantages over conventional battery technologies, including cost and safety concerns. However, conventional RFBs have limited energy densities due to the low solubility of their active species in electrolyte. To overcome this limitation, semi-solid (SSRFBs) and redox targeting (RTFBs) flow batteries have been proposed. These systems feature high concentrations of active species and impressive energy densities, making them highly attractive for renewable energy applications. LiFePO4 (LFP) is a highly promising active material for semi-solid and targeting flow batteries. One of the key advantages of LFP is its low raw materials cost, as it is composed of Earth-abundant elements such as iron and phosphorus. This makes it an attractive option for large-scale battery production. The recent developments in SSRFBs and RTFBs using LFP as catholyte hold great promise for the future of sustainable energy storage. The combination of LFP's low cost, safety, durability, and high energy density with the modularity and scalability of flow battery systems make for a compelling solution to the challenges of intermittent renewable energy sources. Ongoing research and development in this area will likely yield even further improvements in the performance and efficiency of LFP-based flow batteries, opening exciting new possibilities for sustainable energy storage.

El Halya, Nabil↗

Glass Crystallization Constraints for WTP LAW Operations: Assessment of Isothermal Treatments on Crystal Formation

Much work has been done to expand the glass composition region available for operation of the Hanford Waste Treatment and Immobilization Plant. This includes the development of updated glass property-composition models as well as constraints. This report supports this effort by suggesting constraints for avoiding excessive, and likely detrimental, crystallization during melter operation while processing advanced low-activity glass waste forms. The constraints target SnO 2 and ZrO 2 crystals that can form when melter temperatures drop below 1100 °C. These types of crystals were found to be potentially detrimental during processing as they are denser than low-activity waste glass melts. SnO 2 , density of 6.95 g/cm3, and ZrO 2 , density of 5.68 g/cm3, have the potential to form during melter idling and settle to the bottom of the less dense glass melt (approximate density 2.65 g/cm3). If the crystals are present in appreciable amounts, they can result in blockages of the pour-spout riser, which impacts glass pouring and melter operation. Using previously acquired results and results from testing during this effort, constraints were determined and are suggested as options to reduce the risk of forming crystals of the types and concentrations that are likely detrimental to melter operation.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

Decay Dose Shielding Analysis with Hybrid Unstructured Mesh/Constructive Solid Geometry Monte Carlo Calculation and ADVANTG Acceleration

Here, the target segments of the Oak Ridge National Laboratory Second Target Station (STS) neutron production facility become highly activated due to spallation reactions or nuclei transmutation by primary protons and emitted neutrons. Once the target segments are removed from their location within the core vessel, decay dose rates must be accurately quantified to determine the shielding configurations of remote-handling tools and transport casks and to aid in planning maintenance activities. For this analysis, we utilized a hybrid unstructured mesh (UM)/constructive solid geometry approach for calculating spallation products and neutron fluxes, activation calculations using the AARE package that includes the CINDER2008 activation code to calculate the decay photon source at different cooling times, and the ADVANTG code to accelerate the final decay photon transport calculation. Both Type 316 stainless steel (SS-316) and lead were investigated as candidates for shielding materials. The decay photon transport calculation through the thick SS-316 or lead shields exhibited between 25 and 30 orders-of-magnitude attenuations in the radial direction, depending on the shield. Such a difficult shielding calculation required advanced variance reduction. ADVANTG has some missing features, which limits its usability in spallation neutron source applications. It does not support volumetric sources created for MCNP6.2 UM capability. An approximate source was created for this problem. Not only was this approximate source needed for running the ADVANTG calculation to generate the weight windows, but also it was essential to develop source biasing (SB) parameters that were crucial for dramatically accelerating the decay photon transport in this problem. With this approximate source, the analysis was completed in a very reasonable computational time, and the design of the STS remote-handling equipment was finalized. This paper compares the efficiency of Monte Carlo simulations with different weight window and SB parameters calculated using different approximate ADVANTG calculations.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗

Wyoming CarbonSAFE: Advancing Commercialization of Low-Carbon Energy Technologies in Fossil-Rich Wyoming

Wyoming’s Powder River Basin (PRB) is the most prolific coal producer and exporter in the United States and the State of Wyoming’s largest oil-producing basin. In addition to being a leading energy producer, the PRB is the site of research programs whose aim is to develop and integrate low-carbon technologies into existing fossil fuel energy industries. Much of the PRB’s low-carbon research is focused around Dry Fork Station (DFS), which is the newest coal-fired power station in the western US. Currently, DFS hosts five carbon capture projects, including pilot-scale capture projects that utilize different capture technologies and a full front-end engineering and design (FEED) study, a commercial CO 2 pipeline for nearby CO 2 -enhanced oil recovery industry, and is also co-located with the Wyoming Integrated Test Center, which is a host facility for unconventional carbon utilization research (i.e. flue gas carbon-to-products innovations). DFS is also the host site for the Wyoming CarbonSAFE project. Wyoming CarbonSAFE, funded by the Department of Energy/National Energy Technology Laboratory, is a multi-phased program (currently in Phase II) whose core objective is developing and validating storage sites within a complex capable of storing 50 million metric tonnes of CO 2 over a 30 year project period using carbon capture, utilization and storage (CCUS). This paper will provide an overview of the project to-date, showing that CarbonSAFE goals are achievable with respect to geologic, environmental, regulatory, CO 2 source and economic conditions, and why the State of Wyoming offers one of the more favorable environments to advance the commercialization studies. In 2019, the project team designed and completed a ~10,000 foot stratigraphic test well just south of DFS. From this well, the team collected over 600 feet of core, fluid samples from target injection zones, and a full petrophysical log suite. In addition, legacy 2D seismic lines were acquired and a 3D seismic survey was acquired in the fall of 2020. The objective of these field activities has been to identify and characterize target storage reservoirs and associated caprock. This complex has several reservoirs that could meet commercial injection goals, and over 4000 feet of associated caprock. Simulations of site performance suggest that stacked injection provides the most effective storage strategy, and would necessitate several sites within the greater complex to meet final project injection goals. Other work within this project includes the development of a business-case around proximal fields with CO 2 -enhanced oil recovery potential and existing tax credits, assessment of regulatory conditions, including pore space ownership and Class VI injection well permitting requirements, implementation of a robust public outreach Electronic copy available at: https://ssrn.com/abstract=3821220 GHGT-15 McLaughlin 2 program, and surface site characterization activities that have focused on environmental factors. In the PRB and at DFS, the State of Wyoming and other entities have made carbon management a priority of its future energy industry by providing a regulatory and business framework that is favorable to advancing these technologies. These endeavors will become more realistic with the successful implementation of Wyoming CarbonSAFE, and its ability to secure and validate commercial-scale CCUS at the center of Wyoming’s premier low-carbon research efforts.

McLaughlin, Fred↗

Methods for producing radionuclides using minimal targeting material

Among the various aspects of the present disclosure is the provision of methods for producing radioisotopes and improving the specific activity of radioisotopes (e.g., Cu-64 chloride). As described herein, the method includes matching of the target material and the proton beam strike area, resulting in improved specific activity while reducing the amount of target material used.

Gaehle, Gregory↗

Measurement Sets and Sites Commonly Used for Characterization

Scientists at NASA's Earth Science Applications Directorate are creating a well-characterized Verification & Validation (V&V) site at the Stennis Space Center. This site enables the in-flight characterization of remote sensing systems and the data they acquire. The data are predominantly acquired by commercial, high spatial resolution satellite systems, such as IKONOS and QuickBird 2, and airborne systems. The smaller scale of these newer high resolution remote sensing systems allows scientists to characterize the geometric, spatial, and radiometric data properties using a single V&V site. The targets and techniques used to characterize data from these newer systems can differ significantly from the techniques used to characterize data from the earlier, coarser spatial resolution systems. Scientists are also using the SSC V&V site to characterize thermal infrared systems and active LIDAR systems. SSC employs geodetic targets, edge targets, radiometric tarps, and thermal calibration ponds to characterize remote sensing data products. This paper presents a proposed set of required measurements for visible through long-wave infrared remote sensing systems and a description of the Stennis characterization. Other topics discussed include: 1) The use of ancillary atmospheric and solar measurements taken at SSC that support various characterizations; 2) Additional sites used for radiometric, geometric, and spatial characterization in the continental United States; 3) The need for a standardized technique to be adopted by CEOS and other organizations.

Pagnutti, Mary↗

Stennis Space Center Verification & Validation Capabilities

Scientists within NASA s Applied Sciences Directorate have developed a well-characterized remote sensing Verification & Validation (V&V) site at the John C. Stennis Space Center (SSC). This site enables the in-flight characterization of satellite and airborne high spatial and moderate resolution remote sensing systems and their products. The smaller scale of the newer high resolution remote sensing systems allows scientists to characterize geometric, spatial, and radiometric data properties using a single V&V site. The targets and techniques used to characterize data from these newer systems can differ significantly from the techniques used to characterize data from the earlier, coarser spatial resolution systems. Scientists are also using the SSC V&V site to characterize thermal infrared systems and active lidar systems. SSC employs geodetic targets, edge targets, radiometric tarps, atmospheric monitoring equipment, and thermal calibration ponds to characterize remote sensing data products. The SSC Instrument Validation Lab is a key component of the V&V capability and is used to calibrate field instrumentation and to provide National Institute of Standards and Technology traceability. This poster presents a description of the SSC characterization capabilities and examples of calibration data.

Pagnutti, Mary↗

High Resolution Spectroscopy of AGN in Outburst: The Gaseous Nuclear Environment and the WIGM

This grant is associated to a successful XMM-A02 proposal to observe blazars in outburst states, to X-ray the intergalactic medium, searching for intervening ionized absorption. The observation was triggered on August 31 2003, on the blazar 1H 0414+009 (2=0.287), when the target was showing a level of activity of about 20 mCrab in the total XTE-ASM band. The observation was performed 1 day later (on September 1, 2003) and lasted for 79 ks (79 % of the requested time). Unfortunately, assuming that the XTE-ASM notification was real, the target had recovered his quiescent level of approx. 0.35 mCrab, when the XMM RGS observed it. This, combined with the lower-than-requested exposure, produced an XMM-RGS spectrum containing only - 40 counts per resolution element in the 24.1 less than lambda(A) less than 30 range, insufficient to detect even the strongest predicted lines from the OVII WHIM. However, we do detect the Local Group WHIM OVII system in the spectrum of this blazar.

Mushotzky, Richard↗

The Cloud Feedback Model Intercomparison Project (CFMIP) contribution to CMIP6.

The primary objective of CFMIP is to inform future assessments of cloud feedbacks through improved understanding of cloud-climate feedback mechanisms and better evaluation of cloud processes and cloud feedbacks in climate models. However, the CFMIP approach is also increasingly being used to understand other aspects of climate change, and so a second objective has now been introduced, to improve understanding of circulation, regional-scale precipitation, and non-linear changes. CFMIP is supporting ongoing model inter-comparison activities by coordinating a hierarchy of targeted experiments for CMIP6, along with a set of cloud-related output diagnostics. CFMIP contributes primarily to addressing the CMIP6 questions 'How does the Earth system respond to forcing?' and 'What are the origins and consequences of systematic model biases?' and supports the activities of the WCRP Grand Challenge on Clouds, Circulation and Climate Sensitivity. A compact set of Tier 1 experiments is proposed for CMIP6 to address this question: (1) what are the physical mechanisms underlying the range of cloud feedbacks and cloud adjustments predicted by climate models, and which models have the most credible cloud feedbacks? Additional Tier 2 experiments are proposed to address the following questions. (2) Are cloud feedbacks consistent for climate cooling and warming, and if not, why? (3) How do cloud-radiative effects impact the structure, the strength and the variability of the general atmospheric circulation in present and future climates? (4) How do responses in the climate system due to changes in solar forcing differ from changes due to CO2, and is the response sensitive to the sign of the forcing? (5) To what extent is regional climate change per CO2 doubling state-dependent (non-linear), and why? (6) Are climate feedbacks during the 20th century different to those acting on long-term climate change and climate sensitivity? (7) How do regional climate responses (e.g. in precipitation) and their uncertainties in coupled models arise from the combination of different aspects of CO2 forcing and sea surface warming? CFMIP also proposes a number of additional model outputs in the CMIP DECK, CMIP6 Historical and CMIP6 CFMIP experiments, including COSP simulator outputs and process diagnostics to address the following questions. 1. How well do clouds and other relevant variables simulated by models agree with observations? 2. What physical processes and mechanisms are important for a credible simulation of clouds, cloud feedbacks and cloud adjustments in climate models? 3. Which models have the most credible representations of processes relevant to the simulation of clouds? 4. How do clouds and their changes interact with other elements of the climate system?

carbon dioxide↗