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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 469 records · Page 26
All sourcesNASA NTRSDOE OSTI
DOE OSTI2023

Method to Investigate Cognitive Aging Effects in Nuclear Operations Using the Rancor Microworld Simulator

Many nuclear power plant (NPP) operators are close to, or at retirement age. Since NPP operators are responsible for tasks that engage different and complex cognitive abilities, human factors researchers recently called for the need to examine cognitive aging effects and potential interactions with modernized control rooms. One way control rooms are being modernized is by replacing paper-based procedures with computer-based procedures (CBPs). This paper outlines a method for testing preference and usability of three types of CBPs as a function of age, in simulated NPP operations. The Rancor Microworld Simulator will be used, which mimics an NPP control room, allowing novices to learn to perform operator tasks quickly. The experiment will have two independent variables: age (young and old) and CBP-type (Type 1, Type 2, and Type 3). The three types of CBPs vary in levels of embedded instrumentation and controls. Adults aged 18–25 years (young group) and =60 years (older group) will be recruited from the general population. The dependent variables will be preference and usability metrics via survey and simulator logs. All participants will perform two scenario types (startup and loss of feedwater operations) and will be randomly assigned to one type of CBP to guide them through the scenario. Analyses of variance (ANOVAs) will be used to determine whether there is a main effect of age and any age x CBP-type interactions on the preference and usability dependent variables.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗
NASA NTRS1981

Combustion experimentation aboard the space transportation system

A description is presented of the preliminary concept, specifications, and general requirements of a proposed Combustion Facility (CF) for the Spacelab payload of the Space Transportation System. The CF will permit an experimenter to use suitably contained liquid, gas, or solid fuels. He can specify and establish the composition and pressure level of the atmosphere in which the combustion will take place. It will be possible to characterize the experiment with common types of instrumentation as well as selected specialized equipment, to study the combustion process visually by direct observation and by motion picture coverage, and to obtain time histories of pertinent experimental parameters. During an experimental period, the CF will depend on Spacelab resources for power, heat rejection, and vacuum. Activating the CF and preparing it for the various experiments, performing the experiments, and shutting down the facility will be largely manual operations performed by flight personnel.

Dewitt, R. L.↗
NASA NTRS2002

Hypersonic Propulsion at Pratt and Whitney: Overview

Pratt & Whitney (P&W) is developing the technology for hypersonic components and engines. A supersonic combustion ramjet (scramjet) database was developed during the National Aero Space Plane (NASP) program using hydrogen fueled propulsion systems for space access vehicles and serves as a point of departure for the current emphasis on hydrocarbon scramjets. The Air Force Hypersonic Technology (HyTech) Office has put programs in place to develop the technologies necessary to demonstrate the operability, performance and structural durability of a liquid hydrocarbon fueled scramjet system that operates from Mach 4 to 8. Fuel-cooled superalloys and lightweight structures are being developed to improve thermal protection and durability and to reduce propulsion system weight. The application of scramjet engine technology as part of combined cycle propulsion systems is also being pursued under NASA and U.S. Air Force sponsorship. The combination of scramjet power and solid rocket booster acceleration is applicable to hypersonic cruise missiles. Scramjets that use gas turbines for low speed acceleration and scramjets using rocket power for low speed acceleration are being studied for application to reusable launch systems and hypersonic cruise vehicles. P&W's recent activities and future plans for hypersonic propulsion will be described.

Kazmar, Richard R.↗
NASA NTRS2015

SSI-ARC Flight Test 3 Data Review

The "Unmanned Aircraft System (UAS) Integration into the National Airspace System (NAS)" Project conducted flight test program, referred to as Flight Test 3, at Armstrong Flight Research Center from June - August 2015. Four flight test days were dedicated to the NASA Ames-developed Detect and Avoid (DAA) System referred to as Autoresolver. The encounter scenarios, which involved NASA's Ikhana UAS and a manned intruder aircraft, were designed to collect data on DAA system performance in real-world conditions and uncertainties with four different surveillance sensor systems. Resulting flight test data and analysis results will be used to evaluate the DAA system performance (e.g., trajectory prediction accuracy, threat detection) and to add fidelity to simulation models used to inform Minimum Operating Performance Standards (MOPS) for integrating UAS into routine NAS operations.

detect and avoid↗
DOE OSTI2019

Performing optimized collective operations in an irregular subcommunicator of compute nodes in a parallel computer

In a parallel computer, performing optimized collective operations in an irregular subcommunicator of compute nodes may be carried out by: identifying, within the irregular subcommunicator, regular neighborhoods of compute nodes; selecting, for each neighborhood from the compute nodes of the neighborhood, a local root node; assigning each local root node to a node of a neighborhood-wide tree topology; mapping, for each neighborhood, the compute nodes of the neighborhood to a local tree topology having, at its root, the local root node of the neighborhood; and performing a one way, rooted collective operation within the subcommunicator including: performing, in one phase, the collective operation within each neighborhood; and performing, in another phase, the collective operation amongst the local root nodes.

Davis, Kristan D.↗
DOE OSTI2021

Performing optimized collective operations in a irregular subcommunicator of compute nodes in a parallel computer

In a parallel computer, performing optimized collective operations in an irregular subcommunicator of compute nodes may be carried out by: identifying, within the irregular subcommunicator, regular neighborhoods of compute nodes; selecting, for each neighborhood from the compute nodes of the neighborhood, a local root node; assigning each local root node to a node of a neighborhood-wide tree topology; mapping, for each neighborhood, the compute nodes of the neighborhood to a local tree topology having, at its root, the local root node of the neighborhood; and performing a one way, rooted collective operation within the subcommunicator including: performing, in one phase, the collective operation within each neighborhood; and performing, in another phase, the collective operation amongst the local root nodes.

Davis, Kristan Suzanne D.↗
NASA NTRS1980

Solar energy system performance evaluation: Seasonal report for Contemporary Newman, Newman, Georgia

A hot solar heating and hot water system's operational performance from June 1979 through April 1980 is evaluated. Solar energy satisfied 42 percent of the total measure load (hot water plus space heating), which was somewhat higher than the solar fraction of 32 percent. When system losses into the heating space from duct leaks and storage are included, the heating solar fraction increases from 42 to 64 percent. Net electrical energy savings were 5.47 million BTUs.

Source record↗
NASA NTRS2007

The NASA Dryden Flight Research Center Unmanned Aircraft System Service Capabilities

Over 60 years of Unmanned Aircraft System (UAS) expertise at the NASA Dryden Flight Research Center are being leveraged to provide capability and expertise to the international UAS community. The DFRC brings together technical experts, UAS, and an operational environment to provide government and industry a broad capability to conduct research, perform operations, and mature systems, sensors, and regulation. The cornerstone of this effort is the acquisition of both a Global Hawk (Northrop Grumman Corporation, Los Angeles, California) and Predator B (General Atomics Aeronautical Systems, Inc., San Diego, California) unmanned aircraft system (UAS). In addition, a test range for small UAS will allow developers to conduct research and development flights without the need to obtain approval from civil authorities. Finally, experts are available to government and industry to provide safety assessments in support of operations in civil airspace. These services will allow developers to utilize limited resources to their maximum capability in a highly competitive environment.

Bauer, Jeff↗
NASA NTRS2007

The NASA Dryden Flight Research Center Unmanned Aircraft System Service Capabilities

Over 60 years of Unmanned Aircraft System (UAS) expertise at the National Aeronautics and Space Administration (NASA) Dryden Flight Research Center are being leveraged to provide capability and expertise to the international UAS community. The DFRC brings together technical experts, UAS, and an operational environment to provide government and industry a broad capability to conduct research, perform operations, and mature systems, sensors, and regulation. The cornerstone of this effort is the acquisition of both a Global Hawk (Northrop Grumman Corporation, Los Angeles, California) and Predator B (General Atomics Aeronautical Systems, Inc., San Diego, California) unmanned aircraft system (UAS). In addition, a test range for small UAS will allow developers to conduct research and development flights without the need to obtain approval from civil authorities. Finally, experts are available to government and industry to provide safety assessments in support of operations in civil airspace. These services will allow developers to utilize limited resources to their maximum capability in a highly competitive environment.

Bauer, Jeff↗
NASA NTRS2011

Legacy of Operational Space Medicine During the Space Shuttle Program

The Johnson Space Center s Medical Science Division branches were involved in preparing astronauts for space flight during the 30 year period of the Space Shuttle Program. These branches included the Flight Medicine Clinic, Medical Operations and the Behavioral Health Program. The components of each facet of these support services were: the Flight Medicine Clinic s medical selection process and medical care; the Medical Operations equipment, training, procedures and emergency medical services; and the Behavioral Health and Performance operations. Each presenter will discuss the evolution of its operations, implementations, lessons learned and recommendations for future vehicles and short duration space missions.

Stepaniakm, P.↗
NASA NTRSDate not supplied

A Prototype Early Planetary Organic Processor Assembly (OPA) Based on Dual-Stage Anaerobic Membrane Bioreactor (AnMBR) for Fecal and Food Waste Treatment and Resource Recovery

Long-duration, deep-space exploration and habitation missions demand robust and reliable technologies to ensure crew health, safety, and mission success. Local food production will be essential for crew nutrition and morale. However, at $10,000/lb, the payload costs and mass/volume limitations to transport and provide the necessary resources, including fertilizer, for an anticipated 30-month mission become challenging over time. For mission success and sustainability, the Environmental Control and Life Support System (ECLSS) of the near future will need to recover resources from all “waste” sources and be near-closed loop. Organic wastes (e.g., fecal and food) offer a renewable source of C, N, P, water and other trace elements necessary to sustain crop production. However, these high solidwastes are often difficult to treatdue to factors includingheterogeneity, complexity, high organic strength, and the presence of pathogens. To date, there is no flight-ready technology capable of treating mixed organic wastes, creating a technology gap for future space missions. To address this need, a prototype Organic Processor Assembly (OPA) was developed through collaboration between the University of South Florida (USF) and NASA’s Kennedy Space Center (KSC). The OPA is based on the anaerobic membrane bioreactor (AnMBR), a hybrid technology coupling high-rate anaerobic digestion with membrane filtration. The system is designed for an early planetary base (EPB) scenario to aid in closing the resource recovery loop and decreaseresupply dependence. This presentation discusses initial research pertaining to: 1) design challenges in maximizing hydraulic/organic throughputandReliability, Availability, Maintainability, and Safety(RAMS)while minimizingmass and volume; 2) create capabilities for treating simulated high solids waste under steady and non-steady state conditions; and 3) measuresolids performance parameter(s). Future research and development pertaining to further optimization on system operation, performance, and expanded treatment capabilities arepresented.

Bioreactor↗
NASA NTRS1988

Modeling and optimum time performance for concurrent processing

The development of a new graph theoretic model for describing the relation between a decomposed algorithm and its execution in a data flow environment is presented. Called ATAMM, the model consists of a set of Petri net marked graphs useful for representing decision-free algorithms having large-grained, computationally complex primitive operations. Performance time measures which determine computing speed and throughput capacity are defined, and the ATAMM model is used to develop lower bounds for these times. A concurrent processing operating strategy for achieving optimum time performance is presented and illustrated by example.

Mielke, Roland R.↗
NASA NTRS2017

Validation of Minimum Display Requirements for a UAS Detect and Avoid System

The full integration of Unmanned Aircraft Systems (UAS) into the National Airspace System (NAS), a prerequisite for enabling a broad range of public and commercial UAS operations, presents several technical challenges to UAS developers, operators and regulators. A primary barrier is the inability for UAS pilots (situated at a ground control station, or GCS) to comply with Title 14 Code of Federal Regulations sections 91.111 and 91.113, which require pilots to “see and avoid” other aircraft in order to maintain well clear. UAS pilots’ removal from the flight deck of the aircraft necessitates the development of a UAS-specific system for detecting nearby traffic and displaying traffic information to the pilot to support their ability to maintain an objectively defined “DAA well clear” threshold from other aircraft. This new UAS-specific function of remaining DAA well clear is called traffic avoidance. The resulting Detect and Avoid (DAA) system, however, will be subject to a collection of requirements that manufacturers will be obligated to meet in order to certify their equipment. RTCA Special Committee 228 (SC-228), a consortium of representatives from government, industry and academia, is responsible for developing and documenting the Minimum Operational Performance Standards (MOPS) for UAS DAA systems. The present study is the final in a series of human-in-the-loop (HITL) experiments designed to explore and test the various display and alerting requirements being incorporated into the DAA MOPS. Whereas the prior DAA HITLs examined a wide variety of DAA display features and concepts, the current experiment aims to validate the latest minimum display requirements for Phase 1 of the DAA MOPS. Rather than test different display concepts, this study tests two configurations of a MOPS-compatible DAA display: a version that is integrated into the primary navigation and control display of the GCS and a version that is physically separated from the primary display. This manipulation tests the draft minimum requirement that allows the DAA traffic display to be a separate, or standalone, configuration. This type of configuration is a more achievable near-term technology solution since it does not stipulate additional certification or integration requirements on UAS manufacturers. However, a standalone display configuration has the potential to result in pilot performance issues resulting from the cognitive costs of switching between the primary DAA display and the primary navigation and control display. This configuration is also particularly susceptible to errors if the displays are in different orientations (e.g., north-up versus track-up). Both the integrated and standalone display configurations were presented to 16 active UAS pilots in a medium-fidelity simulation, which included confederate air traffic controllers and pseudo pilots operating simulated manned traffic. Pilots were tasked with navigating two different mission routes while maintaining DAA well clear with scripted conflicts. Pilot response times (i.e., measured response) and ability to remain DAA well clear are reported. Primary results indicate that both display configurations resulted in favorable response times and well clear rates. While there were clear trends of pilots objectively performing better in the integrated display condition, with several measured response metrics reaching statistical significance, the differences between the two displays were typically moderate. While the primary variable of DAA display location did not have an especially large impact on pilot performance on its own, when examined alongside the type of DAA threat the pilot was facing (a caution-level versus a warning-level alert), the response time benefits associated with the integrated display were amplified. The implications of these American Institute of Aeronautics and Astronautics 2 results on the Phase 1 DAA MOPS and the connection of this data to previous studies is also discussed.

detect and avoid↗
DOE OSTI2026

Findings from Large Bench-Scale Testing of Denitration Electrolyzers for the EDCGe Project

This report highlights the key findings and outcomes relevant to the processability of waste supernatant at Hanford using a denitration electrolyzer. The Electrosynthesis Company issued a Phase 1 report to the Savannah River National Laboratory (SRNL), summarizing the evaluation of large bench-scale denitration electrolyzers to support the electrochemical denitration and caustic generation (EDCGe) project. The Electrosynthesis Company’s report (attached as Appendix A) provides insights into the initial steps required to implement an electrolyzer system at Hanford. Phase 1 experiments focused on validating the denitration electrolyzer’s performance, operating parameters, and reaction products. The robustness of the electrochemical denitration process was demonstrated by two electrolyzer flow cell systems (a 100 cm 2 ElectroCell MP and a 150 cm 2 NESI NS01 cell), both of which achieved significant nitrate and nitrite removal (>50%) with a current efficiency of ~95% for both systems. Higher current densities (500 mA cm –2 ) improved nitrate and nitrite removal rates compared to lower current densities (333 mA cm –2 ), while maintaining a current efficiency of ~94%. The NS01 cell achieved a nitrate species removal rate of ~0.41 mol h –1 at 5 kA m –2 (equiv. to 500 mA cm –2 ). The primary reaction product was ammonia (NH 3 ), constituting 78.3–91.6% of the products (excluding OH – formation). NH 3 was predominantly retained in the catholyte liquid phase rather than being off-gassed. Additionally, the NS01 cell reported an NH 3 generation rate of ~0.36 mol h –1 at 5 kA m –2 . Other gas formation included ~7% N 2 , ~7% H 2 , and trace amounts of N 2 O. The estimated power requirement (extrapolated from the 0.015 m 2 cell data) for a full-scale denitration electrolyzer is approximated to be ~1.6 MW (DC-only) to treat 50% of nitrate and nitrite in a waste stream and generates ~2.1 kmol h –1 of NH 3 with an initial concentration of 4 M NO 3 – /NO 2 – at 300 gal h –1 . Simulated waste containing aluminate, carbonate, oxalate, and halogens exhibited no adverse effects on denitration performance. A preliminary experiment comparing alkaline anolyte (5 M NaOH) with a nickel based anode to acidic media (2 M H 2 SO 4 ) with a DSA-O 2 anode showed a lower operating voltage and generated less H 2 than the acid media. Maintaining a stable 5 M OH – concentration in the anolyte through periodic additions of caustic did not significantly impact denitration performance. This operational mode will be required for long-term experiments. All the experiments demonstrated that electrochemical denitration is a promising approach for treating nitrate and nitrite in simulated waste streams, achieving significant conversion and robustness across varying experimental conditions and electrochemical cell configurations. Lastly, the ability to generate a nearly pure NH 3 stream may prove advantageous for processing at other locations within the Hanford site.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗