SEARCH · Search NASA

Results for “shared control”

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.

SourceResearch connectionFrom yearThrough year

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,279 records · Page 71

All sources NASA NTRS DOE OSTI

DOE OSTI2021

Diversity, taxonomy, and evolution of archaeal viruses of the class Caudoviricetes

The archaeal tailed viruses (arTV), evolutionarily related to tailed double-stranded DNA (dsDNA) bacteriophages of the class Caudoviricetes , represent the most common isolates infecting halophilic archaea. Only a handful of these viruses have been genomically characterized, limiting our appreciation of their ecological impacts and evolution. Here, we present 37 new genomes of haloarchaeal tailed virus isolates, more than doubling the current number of sequenced arTVs. Analysis of all 63 available complete genomes of arTVs, which we propose to classify into 14 new families and 3 orders, suggests ancient divergence of archaeal and bacterial tailed viruses and points to an extensive sharing of genes involved in DNA metabolism and counterdefense mechanisms, illuminating common strategies of virus–host interactions with tailed bacteriophages. Coupling of the comparative genomics with the host range analysis on a broad panel of haloarchaeal species uncovered 4 distinct groups of viral tail fiber adhesins controlling the host range expansion. The survey of metagenomes using viral hallmark genes suggests that the global architecture of the arTV community is shaped through recurrent transfers between different biomes, including hypersaline, marine, and anoxic environments.

59 BASIC BIOLOGICAL SCIENCES↗

NASA NTRS1989

The Raid distributed database system

Raid, a robust and adaptable distributed database system for transaction processing (TP), is described. Raid is a message-passing system, with server processes on each site to manage concurrent processing, consistent replicated copies during site failures, and atomic distributed commitment. A high-level layered communications package provides a clean location-independent interface between servers. The latest design of the package delivers messages via shared memory in a configuration with several servers linked into a single process. Raid provides the infrastructure to investigate various methods for supporting reliable distributed TP. Measurements on TP and server CPU time are presented, along with data from experiments on communications software, consistent replicated copy control during site failures, and concurrent distributed checkpointing. A software tool for evaluating the implementation of TP algorithms in an operating-system kernel is proposed.

Bhargava, Bharat↗

NASA NTRS1992

The link evaluation terminal for the advanced communications technology satellite experiments program

The experimental NASA satellite, Advanced Communications Technology Satellite (ACTS), introduces new technology for high throughput 30 to 20 GHz satellite services. Contained in a single communication payload is both a regenerative TDMA system and multiple 800 MHz 'bent pipe' channels routed to spot beams by a switch matrix. While only one mode of operation is typical during any experiment, both modes can operate simultaneously with reduced capability due to sharing of the transponder. NASA-Lewis instituted a ground terminal development program in anticipation of the satellite launch to verify the performance of the switch matrix mode of operations. Specific functions are built into the ground terminal to evaluate rain fade compensation with uplink power control and to monitor satellite transponder performance with bit error rate measurements. These functions were the genesis of the ground terminal's name, Link Evaluation Terminal, often referred to as LET. Connectors are included in LET that allow independent experimenters to run unique modulation or network experiments through ACTS using only the RF transmit and receive portions of LET. Test data indicate that LET will be able to verify important parts of ACTS technology and provide independent experimenters with a useful ground terminal. Lab measurements of major subsystems integrated into LET are presented. Bit error rate is measured with LET in an internal loopback mode.

May, Brian D.↗

NASA NTRS1992

The Link Evaluation Terminal for the Advanced Communications Technology Satellite Experiments Program

May, Brian D.↗

NASA NTRS2018

International Space Station Medical Projects - Full Services to Mars

The International Space Station Medical Projects (ISSMP) Element provides planning, integration, and implementation services for HRP research studies for both spaceflight and flight analog research. Through the implementation of these two efforts, ISSMP offers an innovative way of guiding research decisions to meet the unique challenges of understanding the human risks to space exploration. Flight services provided by ISSMP include leading informed consent briefings, developing and validating in-flight crew procedures, providing ISS crew and ground-controller training, real-time experiment monitoring, on-orbit experiment and hardware operations and facilitating data transfer to investigators. For analog studies at the NASA Human Exploration Research Analog (HERA), the ISSMP team provides subject recruitment and screening, science requirements integration, data collection schedules, data sharing agreements, mission scenarios and facilities to support investigators. The ISSMP also serves as the HRP interface to external analog providers including the :envihab bed rest facility (Cologne, Germany), NEK isolation chamber (Moscow, Russia) and the Antarctica research stations. Investigators working in either spaceflight or analog environments requires a coordinated effort between NASA and the investigators. The interdisciplinary nature of both flight and analog research requires investigators to be aware of concurrent research studies and take into account potential confounding factors that may impact their research objectives. Investigators must define clear research requirements, participate in Investigator Working Group meetings, obtain human use approvals, and provide study-specific training, sample and data collection and procedures all while adhering to schedule deadlines. These science requirements define the technical, functional and performance operations to meet the research objectives. The ISSMP maintains an expert team of professionals with the knowledge and experience to guide investigators science through all aspects of mission planning, crew operations, and research integration. During this session, the ISSMP team will discuss best-practices approaches for successfully preparing and conducting studies in both the flight and analog environments. Critical tips and tricks will be shown to greatly improve your chances of successfully completing your research aboard the International Space Station and in Spaceflight Analogs.

Pietrzyk, R. A.↗

NASA NTRS2018

Radio-hosted Flight / Ground Interface for Operations Standardization

The interface between a spacecraft and its ground operations segment includes the flow of commands, configuration, and sequencing elements to the spacecraft, and the flow of telemetry and data products from the spacecraft. Creating and implementing a complete definition of this interface simplifies and standardizes mission operations, allowing easy sharing of operations personnel across missions. Early spacecraft featured a simple flight / ground interface (FGI) using hardware command decoding in the radio, driven by technological limitations of the time. Modern spacecraft use command and data handling (CDH) avionics on which flight software executes, which in turn controls and configures the mission, executes subsystem and instrument instructions, and implements critical fault protection actions. Deep space missions feature advanced operations software for running sequenced activities over a period of weeks, which allows them to function with only infrequent ground contact. This approach comes at the cost of increased complexity in the FGI, requiring expensive modifications to heritage flight software and ground systems. By hosting the interface in the radio instead of the CDH avionics, modern missions can approximate the FGI design simplicity of early spacecraft, with significant advantages for vendor competition, lowered costs, standardization of operations, and reduction of implementation risk.

Lock, Patricia D.↗

DOE OSTI2014

ISO 50001 for Commercial Buildings: Lessons Learned From U.S. DOE Pilot Project: Preprint

In the U.S., the ISO 50001 Standard, which establishes energy management systems (EnMSs) and processes, has shown uptake primarily in the industrial sector. The U.S. Department of Energy (DOE) undertook a pilot program to explore ISO 50001 implementation in commercial buildings. Eight organizations participated as pilots, with technical assistance provided by DOE, the National Renewable Energy Laboratory (NREL), the Lawrence Berkeley National Laboratory (LBNL), and the Georgia Institute of Technology (Georgia Tech). This paper shares important lessons learned from the pilot. Staff time was the most critical resource required to establish effective EnMSs in commercial buildings. The pilot also revealed that technical support and template/example materials were essential inputs. Crucial activities included evaluating performance, identifying goals, making connections, communicating operational controls, and tracking/reviewing progress. Benefits realized included enhanced intra-organizational connections, greater energy awareness, increased process efficiencies, and improved ability to make business cases. Incremental benefits for ISO 50001 certification were greater accountability, assurance of best practices, public relations opportunities, and potential to unlock verified savings credits or incentive money. Incremental certification costs included more staff/consultant time, money for certification, and a tendency to limit EnMS scope in order to ensure favorable audit results. Five best practices were identified - utilizing expert technical assistance, training, and other resources; focusing on implementation over documentation; keeping top management involved; considering organizational structure when selecting EnMS scope; and matching the implementation level to an EnMS's scope and scale. The last two practices are particularly relevant to the commercial buildings sector.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗

DOE OSTI2017

Sustained Low Temperature NOx Reduction

Increasing regulatory, environmental, and customer pressure in recent years led to substantial improvements in the fuel efficiency of diesel engines, including the remarkable breakthroughs demonstrated through the Super Truck program supported by the U.S. Department of Energy (DOE). On the other hand, these improvements have translated into a reduction of exhaust gas temperatures, thus further complicating the task of controlling NOx emissions, especially in low power duty cycles. The need for improved NOx conversion over these low temperature duty cycles is also observed as requirements tighten with in-use emissions testing. Sustained NOx reduction at low temperatures, especially in the 150-200oC range, shares some similarities with the more commonly discussed cold-start challenge, however poses a number of additional and distinct technical problems. In this project we set a bold target of achieving and maintaining a 90% NOx conversion at the SCR catalyst inlet temperature of 150oC. The project is intended to push the boundaries of the existing technologies, while staying within the realm of realistic future practical implementation. In order to meet the resulting challenges at the levels of catalyst fundamentals, system components, and system integration, Cummins has partnered with the DOE, Johnson Matthey, and Pacific Northwest National Lab and initiated the Sustained Low-Temperature NOx Reduction program at the beginning of 2015. Through this collaboration, we are exploring catalyst formulations and catalyst architectures with enhanced catalytic activity at 150°C; opportunities to approach the desirable ratio of NO and NO2 in the SCR feed gas; options for robust low-temperature reductant delivery; and the requirements for overall system integration. The program is expected to deliver an on-engine demonstration of the technical solution and an assessment of its commercial potential. In the SAE meeting, we will share the initial performance data on engine to highlight the path to achieve 90% NOx conversion at the SCR inlet temperature of 150oC.

Zha, Yuhui↗

NASA NTRS1990

Implementation and integration of a counterbalanced CRT-based stereoscopic display for interactive viewpoint control in virtual environment applications

The NASA-Ames Counterbalanced CRT-based Stereoscopic Viewer (CCSV), which is being used as a viewing device for biomechanical CAD environments, is uniquely suited for applications in which the user frequently moves between desk work and virtual environment viewing, or in which high resolution views of the virtual environment are required, or in which the viewing device must be shared among collaborators in a group setting. The CCSV hardware encompasses a dual-CRT-based stereoscopic viewer with wide-angle optics, a video electronics box, a dedicated microprocessor system monitoring joint angles in the linkage, and a host computer interpreting sensor values and running the application which renders the right and left views for reader CRTs.

Mcdowall, I. E.↗

DOE OSTI2013

Single-faced GRAYQB™: a radiation mapping device

GrayQb{trademark} is a novel technology that has the potential to characterize radioactively contaminated areas such as hot cells, gloveboxes, small and large rooms, hallways, and waste tanks. The goal of GrayQb{trademark} is to speed the process of decontaminating these areas, which reduces worker exposures and promotes ALARA considerations. The device employs Phosphorous Storage Plate (PSP) technology as its primary detector material. PSPs, commonly used for medical applications and non-destructive testing, can be read using a commercially available scanner. The goal of GrayQb{trademark} technology is to locate, quantify, and identify the sources of contamination. The purpose of the work documented in this report was to better characterize the performance of GrayQb{trademark} in its ability to present overlay images of the PSP image and the associated visual image of the location being surveyed. The results presented in this report are overlay images identifying the location of hot spots in both controlled and field environments. The GrayQb{trademark} technology has been mainly tested in a controlled environment with known distances and source characteristics such as specific known radionuclides, dose rates, and strength. The original concept for the GrayQb{trademark} device involved utilizing the six faces of a cube configuration and was designed to be positioned in the center of a contaminated area for 3D mapping. A smaller single-faced GrayQb{trademark}, dubbed GrayQb SF, was designed for the purpose of conducting the characterization testing documented in this report. This lighter 2D version is ideal for applications where entry ports are too small for a deployment of the original GrayQb™ version or where only a single surface is of interest. The shape, size, and weight of these two designs have been carefully modeled to account for most limitations encountered in hot cells, gloveboxes, and contaminated areas. GrayQb{trademark} and GrayQb{trademark} SF share the same fundamental detection system design (e.g., pinhole and PSPs). Therefore, performance tests completed on the single face GrayQB in this report is also applicable to the six- faced GrayQB (e.g., ambient light sensitivity and PSP response). This report details the characterization of the GrayQb{trademark} SF in both an uncontrolled environment; specifically, the Savannah River Site (SRS) Plutonium Fuel Form Facility in Building 235-F (Metallurgical Building) and controlled testing at SRS’s Health Physics Instrument Calibration Facility and SRS’s R&D Engineering Imaging and Radiation Systems Building. In this report, the resulting images from the Calibration Facility were obtained by overlaying the PSP and visual images manually using ImageJ. The resulting images from the Building 235-F tests presented in this report were produced using ImageJ and applying response trends developed from controlled testing results. The GrayQb{trademark} technology has been developed in two main stages at Savannah River National Laboratory (SRNL): 1) the GrayQb{trademark} development was supported by SRNL’s Laboratory Directed Research and Development Program and 2) the GrayQb{trademark} SF development and its testing in Building 235-F were supported by the Office of Deactivation and Decommissioning and Facility Engineering (EM-13), U.S. Department of Energy – Office of Environmental Management.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗

DOE OSTI2017

An Algorithm of an X-ray Hit Allocation to a Single Pixel in a Cluster and Its Test-Circuit Implementation

An on-chip implementable algorithm for allocation of an X-ray photon imprint, called a hit, to a single pixel in the presence of charge sharing in a highly segmented pixel detector is described. Its proof-of-principle implementation is also given supported by the results of tests using a highly collimated X-ray photon beam from a synchrotron source. The algorithm handles asynchronous arrivals of X-ray photons. Activation of groups of pixels, comparisons of peak amplitudes of pulses within an active neighborhood and finally latching of the results of these comparisons constitute the three procedural steps of the algorithm. A grouping of pixels to one virtual pixel, that recovers composite signals and event driven strobes, to control comparisons of fractional signals between neighboring pixels are the actuators of the algorithm. The circuitry necessary to implement the algorithm requires an extensive inter-pixel connection grid of analog and digital signals, that are exchanged between pixels. A test-circuit implementation of the algorithm was achieved with a small array of 32 × 32 pixels and the device was exposed to an 8 keV highly collimated to a diameter of 3-μm X-ray beam. Furthermore, the results of these tests are given in this paper assessing physical implementation of the algorithm.

47 OTHER INSTRUMENTATION↗

DOE OSTI2024

LevSeq: Rapid Generation of Sequence-Function Data for Directed Evolution and Machine Learning

Sequence-function data provides valuable information about the protein functional landscape but is rarely obtained during directed evolution campaigns. Here, we present Long-read every variant Sequencing (LevSeq), a pipeline that combines a dual barcoding strategy with nanopore sequencing to rapidly generate sequence-function data for entire protein-coding genes. LevSeq integrates into existing protein engineering workflows and comes with open-source software for data analysis and visualization. The pipeline facilitates data-driven protein engineering by consolidating sequence-function data to inform directed evolution and provide the requisite data for machine learning-guided protein engineering (MLPE). LevSeq enables quality control of mutagenesis libraries prior to screening, which reduces time and resource costs. Simulation studies demonstrate LevSeq’s ability to accurately detect variants under various experimental conditions. Lastly, we show LevSeq’s utility in engineering protoglobins for new-to-nature chemistry. Widespread adoption of LevSeq and sharing of the data will enhance our understanding of protein sequence-function landscapes and empower data-driven directed evolution.

59 BASIC BIOLOGICAL SCIENCES↗

DOE OSTI2022

Low Thermal Conductivity in Heteroanionic Materials with Layers of Homoleptic Polyhedra

Although BiAgOSe, an analogue of a well-studied thermoelectric material BiCuOSe, is thermodynamically stable, its synthesis is complicated by the low driving force of formation from the stable binary and ternary intermediates. Here we have developed a “subtraction strategy” to suppress byproducts and produce pure phase BiAgOSe using hydrothermal methods. Electronic structure calculations and optical characterization show that BiAgOSe is an indirect bandgap semiconductor with a bandgap of 0.95 eV. The prepared sample exhibits lower lattice thermal conductivities (0.61 W·m –1 ·K –1 at room temperature and 0.35 W·m –1 ·K –1 at 650 K) than BiCuOSe. Further, lattice dynamical simulations and variable temperature diffraction measurements demonstrate that the low lattice thermal conductivity arises from both the low sound velocity and high phonon–phonon scattering rates in BiAgOSe. These in turn result primarily from the soft Ag–Se bonds in the edge-sharing AgSe 4 tetrahedra and large sublattice mismatch between the quasi-two-dimensional [Bi 2 O 2 ] 2+ and [Ag 2 Se 2 ] 2– layers. These results highlight the advantages of manipulating the chemistry of homoleptic polyhedra in heteroanionic compounds for electronic structure and phonon transport control.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

DOE OSTI2017

Additive Manufacturing of Fuel Injectors

Additive manufacturing (AM), also known as 3D-printing, has been shifting from a novelty prototyping paradigm to a legitimate manufacturing tool capable of creating components for highly complex engineered products. An emerging AM technology for producing metal parts is the laser powder bed fusion (L-PBF) process; however, industry manufacturing specifications and component design practices for L-PBF have not yet been established. Solar Turbines Incorporated (Solar), an industrial gas turbine manufacturer, has been evaluating AM technology for development and production applications with the desire to enable accelerated product development cycle times, overall turbine efficiency improvements, and supply chain flexibility relative to conventional manufacturing processes (casting, brazing, welding). Accordingly, Solar teamed with EWI on a joint two-and-a-half-year project with the goal of developing a production L-PBF AM process capable of consistently producing high-nickel alloy material suitable for high temperature gas turbine engine fuel injector components. The project plan tasks were designed to understand the interaction of the process variables and their combined impact on the resultant AM material quality. The composition of the high-nickel alloy powders selected for this program met the conventional cast Hastelloy X compositional limits and were commercially available in different particle size distributions (PSD) from two suppliers. Solar produced all the test articles and both EWI and Solar shared responsibility for analyzing them. The effects of powder metal input stock, laser parameters, heat treatments, and post-finishing methods were evaluated. This process knowledge was then used to generate tensile, fatigue, and creep material properties data curves suitable for component design activities. The key process controls for ensuring consistent material properties were documented in AM powder and process specifications. The basic components of the project were: • Powder metal input stock: Powder characterization, dimensional accuracy, metallurgical characterization, and mechanical properties evaluation. • Process parameters: Laser parameter effects, post-printing heat-treatment development, mechanical properties evaluation, and post-finishing technique. • Material design curves: Room and elevated temperature tensiles, low cycle fatigue, and creep rupture properties curves generated. • AM specifications: Key metal powder characteristics, laser parameters, and heat-treatment controls identified.

36 MATERIALS SCIENCE↗

DOE OSTI2018

Connecting LWRS Human Factor Engineering R&D to NUREG-0711 Elements and Modification Activities in Nuclear Power Plants

This Report documents the connection between DOE INL LWRS HFE R&D activities and the technical content of NUREG-0711 Results Summary Reports. Since the current and most recent LWRS HFE activities are associated with modernization and modification of nuclear power electric generating stations, this Report will limit its scope to these topics. NUREG-0711 Results Summary Reports content is shared with US nuclear generating stations by INL HFE staff through HFE Technical Reports to identify potential HEDs with planned upgrades. With such information, utilities have confidence that their upgraded HMIs, operating procedures, conduct of operations, and training with the upgraded systems will ensure their continued safe control of the nuclear plant. The utilities use the HFE Technical Reports as basis documents in their licensing processes used to modify the plant (LAR or 10CFR50.59). For plant modifications, LWRS HFE R&D activities commence as early as an agreement is reached between the utility and the LWRS Program staff. The multiple interfaces usually result in the two organizations meeting at INL, at the utility’s site, and at the vendor’s facility. Since there generally is a shortage of utility based HFE experience, INL HFE staff supports the HFE related utility modernization & modification (obsolescence) activities whenever requested.

10 CFR 50.59↗

DOE OSTI2026

Protocol for Engineered Compositional Asymmetry Within Nanodiscs

Membrane proteins remain the most challenging targets for structural characterization, yet their elucidation provides valuable insights into protein function, disease mechanisms, and drug specificity. Structural biology platforms have advanced rapidly in recent years, notably through the development and implementation of nanodiscs—discoidal lipid–protein complexes that encapsulate and solubilize membrane proteins within a controlled, native-like environment. While nanodiscs have become powerful tools for studying membrane proteins, faithfully reconstituting the compositional asymmetry intrinsic to nearly all biological membranes has not yet been achieved. Proper membrane leaflet lipid distribution is critical for accurate protein folding, stability, and insertion. Here, we share a protocol for reconstituting tailored compositional asymmetry within nanodiscs through membrane extraction from giant unilamellar vesicles (GUVs) treated with a leaflet-specific methyl-β-cyclodextrin (mβCD) lipid exchange. Nanodisc asymmetry is verified through a geometric approach: biotin-DPPE-preloaded mβCD engages in lipid exchange with the outer leaflet of POPC GUVs solubilized by the lipid-free membrane scaffold protein (MSP) Δ49ApoA-I to form nanodisc structures. Once isolated, nanodiscs are introduced to the biotin-binding bacterial protein streptavidin. High-speed atomic force microscopy imaging depicts nanodisc–dimer complexes, indicating that biotin-DPPE was successfully reconstituted into a single leaflet of the nanodiscs. This finding outlines the first step toward engineering tailored nanodisc asymmetry and mimicking the native environment of integral proteins—a potentially powerful tool for accurately reconstituting and structurally analyzing integral membrane proteins whose functions are modulated by lipid asymmetry.

Biological and medical sciences↗

NASA NTRS1989

Design for steering accuracy in antenna arrays using shared optical phase shifters

Uniform linear phased arrays where many radiating elements share a relatively small number of phase shifters are investigated. Such architectures arise in arrays which derive the time delays in the signal paths from a small group of independent phase shifters. In particular, a true time-delay device which has been suggested recently for optically controlled arrays is used as the basic phase shifter. Different architectures, viz. alternative procedures of deriving the necessary time delay for each antenna in the face of phase-shifter inaccuracies, are examined. The variance of the steered beam's direction is used as the performance criterion. The direction-optimal architecture is obtained by means of quadratic programming, and is shown not to be unique. The nonuniqueness of the optimal architecture is exploited to improve other characteristics of the array's beam shape, and the optimal solution is shown to compare favorably with a suboptimal interleaved solution which is easier to implement.

Kam, Moshe↗

NASA NTRS1994

High Performance FORTRAN

High performance FORTRAN is a set of extensions for FORTRAN 90 designed to allow specification of data parallel algorithms. The programmer annotates the program with distribution directives to specify the desired layout of data. The underlying programming model provides a global name space and a single thread of control. Explicitly parallel constructs allow the expression of fairly controlled forms of parallelism in particular data parallelism. Thus the code is specified in a high level portable manner with no explicit tasking or communication statements. The goal is to allow architecture specific compilers to generate efficient code for a wide variety of architectures including SIMD, MIMD shared and distributed memory machines.

Mehrotra, Piyush↗