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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 OSTI2014

Underground Test Area Fiscal Year 2013 Annual Quality Assurance Report Nevada National Security Site, Nevada, Revision 0

This report is required by the Underground Test Area (UGTA) Quality Assurance Plan (QAP) and identifies the UGTA quality assurance (QA) activities for fiscal year (FY) 2013. All UGTA organizations—U.S. Department of Energy (DOE), National Nuclear Security Administration Nevada Field Office (NNSA/NFO); Desert Research Institute (DRI); Lawrence Livermore National Laboratory (LLNL); Los Alamos National Laboratory (LANL); Navarro-Intera, LLC (N-I); National Security Technologies, LLC (NSTec); and the U.S. Geological Survey (USGS)—conducted QA activities in FY 2013. The activities included conducting assessments, identifying findings and completing corrective actions, evaluating laboratory performance, and publishing documents. In addition, integrated UGTA required reading and corrective action tracking was instituted.

54 ENVIRONMENTAL SCIENCES↗
NASA NTRS1989

Integrated Cryogenic Experiment (ICE) microsphere investigation

The main objective is to determine the performance of microsphere insulation in a 0-g environment and compare its performance to reference insulations such as multilayer insulation. The Lockheed Helium Extended-Life Dewar (HELD) is used to provide superfluid-helium cold sink for the experiment. The use of HELD allows the low-g dynamic properties of Passive Orbital Disconnect Struts (PODS) to be characterized and provides a flight demonstration of the PODS system. The thermal performance of microspheres in 1 and 0 g was predicted, a flight experiment was designed to determine microsphere thermal performance, and the interface was also designed between the experimental package and the shuttle through HELD and the Hitchhiker-M carrier. A single test cell was designed and fabricated. The cell was filled with uncoated glass microspheres and tested with a liquid-nitrogen cold sink. The data were found to agree with predictions of microsphere performance in 1 g.

Spradley, I.↗
NASA NTRS1959

Investigation of the Characteristics of an Acceleration-Type Take-Off Indicator in a Large Jet Airplane

The characteristics of a proposed acceleration-type take-off indicator were observed during take-off runs of a large jet airplane. The instrument performed its function satisfactorily. It showed an essentially constant reading, which agreed closely with the predicted value, throughout the take-off except for about the first 135 feet of the ground roll during which the starting windup of the indicator pointer occurred. Although oscillating longitudinal accelerations at the instrument location were as much as +/- 50 percent of the steady-state acceleration, the instrument showed only small excursions from the mean reading equivalent to not more than +/- 5 percent of the mean reading and was considered to be satisfactorily readable.

Kolnick, Joseph J.↗
NASA NTRS2011

Magnetically Coupled Calorimeters

Calorimeters that utilize the temperature sensitivity of magnetism have been under development for over 20 years. They have targeted a variety of different applications that require very high resolution spectroscopy. I will describe the properties of this sensor technology that distinguish it from other low temperature detectors and emphasize the types of application to which they appear best suited. I will review what has been learned so far about the best materials, geometries, and read-out amplifiers and our understanding of the measured performance and theoretical limits. I will introduce some of the applications where magnetic calorimeters are being used and also where they are in development for future experiments. So far, most magnetic calorimeter research has concentrated on the use of paramagnets to provide temperature sensitivity; recent studies have also focused on magnetically coupled calorimeters that utilize the diamagnetic response of superconductors. I will present some of the highlights of this research, and contrast the properties of the two magnetically coupled calorimeter types.

Bandler, Simon↗
NASA NTRS2006

Tracking Positions and Attitudes of Mars Rovers

The Surface Attitude Position and Pointing (SAPP) software, which runs on computers aboard the Mars Exploration Rovers, tracks the positions and attitudes of the rovers on the surface of Mars. Each rover acquires data on attitude from a combination of accelerometer readings and images of the Sun acquired autonomously, using a pointable camera to search the sky for the Sun. Depending on the nature of movement commanded remotely by operators on Earth, the software propagates attitude and position by use of either (1) accelerometer and gyroscope readings or (2) gyroscope readings and wheel odometry. Where necessary, visual odometry is performed on images to fine-tune the position updates, particularly on high-wheel-slip terrain. The attitude data are used by other software and ground-based personnel for pointing a high-gain antenna, planning and execution of driving, and positioning and aiming scientific instruments.

Ali, Khaled↗
NASA NTRS2012

Optical Measurements of Tumbling Rocket Bodies

A component of interest in the active debris removal (ADR) effort in low Earth orbit is spent rocket upper stages. Proximity operations for such missions require an understanding of the tumbling characteristics of these targets. This research was conducted to assist in laying the ground work for realistic ADR mission planning. To better understand the tumbling characteristics of these spent upper stages, the NASA Orbital Debris Program Office has acquired over 400 recorded lightcurves using telescopes located in Colorado and New Mexico. This effort focuses on a population of over 250 Russian SL-8 and SL-16 spent upper stages. The oldest of these have been in orbit for 45 years, and some have exhibited unplanned orbit changes up to 22 years after launch. This paper describes the techniques of how this optical data was acquired and summarizes the optical signatures for this population of targets, including categorization, tumbling period, and investigations into specific targets in which the optical signature changed dramatically over different time periods. Results from period analysis performed on these lightcurves are summarized.

Read, J.↗
NASA NTRS2012

Magnetically Coupled Microcalorimeters

Magnetic calorimeters have been under development for over 20 years targeting a wide variety of different applications that require very high resolution spectroscopy. They have a number of properties that distinguish them from other 10w temperature detectors. In this paper we review these properties and emphasize the types of application to which they are most suited. We will describe what has been learned about the best materials, geometries, and read-out amplifiers and our understanding of the measured performance and theoretical limits. While most magnetic calorimeter research has concentrated on the use of paramagnets to provide the temperature sensitivity, recently magnetically coupled microcalorimeters have been in development that utilize the diamagnetic response of superconductors. We will contrast some of the properties of the two different magnetic sensor types.

Bandler, S. R.↗
NASA NTRS2014

New and Better Near-Infrared Detectors for JWST Near Infrared Spectrograph

ESA and NASA recently selected two 5 m cutoff Teledyne H2RG sensor chip assemblies (SCA) for flight on the James Webb Space Telescope (JWST) Near Infrared Spectrograph (NIRSpec). These HgCdTe SCAs incorporate Teledynes improved barrier layer design that eliminates the degradation that affected earlier JWST H2RGs(Rauscher et al. 2012a). The better indium barrier, together with other design changes, has improved the performance and reliability of JWSTs SCAs. In this article, we describe the measured performance characteristics that most directly affect scientific observations including read noise, total noise, dark current, quantum efficiency (QE), and image persistence. As part of measuring QE, we measured the quantum yield as a function of photon energy,, and found that it exceeds unity for photon energies E (2.65.2) Eg, where Eg is the HgCdTe bandgap energy. This corresponds to. 2 m for NIRSpecs 5 m cutoff HgCdTe. Our measurements agree well with a previous measurement by McCullough et al. (2008) for. 1.3. For 1.3, we find a slower increase in with photon energy than McCullough et al. did. However, and as McCullough et al. note, their two state model of the yield process is not valid for large 1.

New and Better↗
NASA NTRS2014

Compact Multi-Gas Monitor for Life Support Systems Control in Space: Evaluation Under Realistic Environmental Conditions

Advanced space life support systems require lightweight, low-power, durable sensors for monitoring critical gas components. A luminescence-based optical flow-through cell to monitor carbon dioxide, oxygen, and humidity has been developed and was demonstrated using bench-top instrumentation under environmental conditions relevant to portable life support systems, including initially pure oxygen atmosphere, temperature range from 50 F to 150 F, and humidity from dry to 100% RH and under conditions of water condensation. This paper presents the most recent progress in the development of this sensor technology. Trace gas contaminants in a space suit, originating from hardware and material off-gassing and crew member metabolism, are from many chemical families. The result is a gas mix much more complex than the pure oxygen fed into the space suit, and this complexity may interfere with gas sensor readings. This paper presents an evaluation of optical sensor performance when exposed to the most significant trace gases reported to be found in space suits. A study of the calibration stability of the sensors is also presented. For that purpose, a profile of temperature, pressure, humidity, and gas composition for the duration of an EVA has been defined, and the performance of sensors operated repeatedly under those conditions has been studied. Finally, this paper presents the first compact readout unit for these optical sensors, designed for the volume, power, and weight restrictions of a PLSS.

Alonso, Jesus Delgado↗
DOE OSTI2015

FireHose Streaming Benchmarks

The FireHose Streaming Benchmarks are a suite of stream-processing benchmarks defined to enable comparison of streaming software and hardware, both quantitatively vis-a-vis the rate at which they can process data, and qualitatively by judging the effort involved to implement and run the benchmarks. Each benchmark has two parts. The first is a generator which produces and outputs datums at a high rate in a specific format. The second is an analytic which reads the stream of datums and is required to perform a well-defined calculation on the collection of datums, typically to find anomalous datums that have been created in the stream by the generator. The FireHose suite provides code for the generators, sample code for the analytics (which users are free to re-implement in their own custom frameworks), and a precise definition of each benchmark calculation.

Karl Anderson, Steve Plimpton↗
DOE OSTI2023

Optimized self-designing key-value storage engine

Embodiments of the invention utilize an optimized key-value storage engine to strike the optimal balance between cloud-cost and performance and supports queries, including updates, lookups, range queries, inserts, and read-modify-writes. Cloud cost is manifested in purchasing both storage and processing resources. The improved approach has the ability to self-design and instantiate holistic configurations given a workload, a cloud budget, and optionally performance goals and a set of Service Level Agreement (SLA) specifications. A configuration reflects an optimized storage engine design in terms of, for example, the individual data structures design (in-memory and on-disk) in the engine as well as their algorithms and interactions, a cloud provider, and the exact virtual machines to be used.

Idreos, Stratos↗
DOE OSTI2025

CMS HGCAL ECON-D ASIC : Impact of CMOS fabrication process tuning on performance and radiation tolerance

The CMS experiment’s High Granularity Calorimeter (HGCAL) upgrade will replace CMS’s existing endcap calorimeters in preparation for the High Luminosity LHC. To effectively use over 6 million channels of this “imaging”calorimeter, CMS has developed two novel Endcap Concentrator (ECON) ASICs to perform data compression/selection on detector. The ECON-D ASIC operates on the 750kHz data path, and the ECON-T ASIC on the 40MHz trigger path. These 65 nm CMOS ASICs are radiation tolerant to 200 Mrad and low power, operating at less than 2.5 mW/channel. The first full-functionality prototype ECONs were produced and characterized in 2021-23, and an initial engineering run was performed in 2024. ECON-D radiation testing for the engineering run revealed that the chip’s internal SRAMs produce intermittent read errors for a non-negligible fraction of chips. Further investigation indicated that the SRAM performance is highly sensitive to the exact parameters of the CMOS fabrication process. To both study this process sensitivity and mitigate SRAM performance issues, twenty ECON wafers were produced in 2025 with a range of doping concentrations designed to tune the underlying transistor threshold voltage by 0%, 5%, 10%, and 15% from nominal. This talk will present first measurements of ECON-D performance, power consumption, and radiation tolerance for these four variations of CMOS process.

Syal, Chinar [Fermilab]↗
DOE OSTI2018

Systematic and stochastic influences on the performance of the MinION nanopore sequencer across a range of nucleotide bias

Emerging sequencing technologies are allowing us to characterize environmental, clinical and laboratory samples with increasing speed and detail, including real-time analysis and interpretation of data. One example of this is being able to rapidly and accurately detect a wide range of pathogenic organisms, both in the clinic and the field. Genomes can have radically different GC content however, such that accurate sequence analysis can be challenging depending upon the technology used. Here, we have characterized the performance of the Oxford MinION nanopore sequencer for detection and evaluation of organisms with a range of genomic nucleotide bias. We have diagnosed the quality of base-calling across individual reads and discovered that the position within the read affects base-calling and quality scores. Finally, we have evaluated the performance of the current state-of-the-art neural network-based MinION basecaller, characterizing its behavior with respect to systemic errors as well as context- and sequence-specific errors. Overall, we present a detailed characterization the capabilities of the MinION in terms of generating high-accuracy sequence data from genomes with a wide range of nucleotide content. This study provides a framework for designing the appropriate experiments that are the likely to lead to accurate and rapid field-forward diagnostics.

59 BASIC BIOLOGICAL SCIENCES↗
NASA NTRS2007

Visual Acuity Using Head-fixed Displays During Passive Self and Surround Motion

The ability to read head-fixed displays on various motion platforms requires the suppression of vestibulo-ocular reflexes. This study examined dynamic visual acuity while viewing a head-fixed display during different self and surround rotation conditions. Twelve healthy subjects were asked to report the orientation of Landolt C optotypes presented on a micro-display fixed to a rotating chair at 50 cm distance. Acuity thresholds were determined by the lowest size at which the subjects correctly identified 3 of 5 optotype orientations at peak velocity. Visual acuity was compared across four different conditions, each tested at 0.05 and 0.4 Hz (peak amplitude of 57 deg/s). The four conditions included: subject rotated in semi-darkness (i.e., limited to background illumination of the display), subject stationary while visual scene rotated, subject rotated around a stationary visual background, and both subject and visual scene rotated together. Visual acuity performance was greatest when the subject rotated around a stationary visual background; i.e., when both vestibular and visual inputs provided concordant information about the motion. Visual acuity performance was most reduced when the subject and visual scene rotated together; i.e., when the visual scene provided discordant information about the motion. Ranges of 4-5 logMAR step sizes across the conditions indicated the acuity task was sufficient to discriminate visual performance levels. The background visual scene can influence the ability to read head-fixed displays during passive motion disturbances. Dynamic visual acuity using head-fixed displays can provide an operationally relevant screening tool for visual performance during exposure to novel acceleration environments.

Wood, Scott J.↗
NASA NTRS1993

Read buffer optimizations to support compiler-assisted multiple instruction retry

Multiple instruction retry is a recovery mechanism for transient processor faults. We previously developed a compiler-assisted approach to multiple instruction ferry in which a read buffer of size 2N (where N represents the maximum instruction rollback distance) was used to resolve some data hazards while the compiler resolved the remaining hazards. The compiler-assisted scheme was shown to reduce the performance overhead and/or hardware complexity normally associated with hardware-only retry schemes. This paper examines the size and design of the read buffer. We establish a practical lower bound and average size requirement for the read buffer by modifying the scheme to save only the data required for rollback. The study measures the effect on the performance of a DECstation 3100 running ten application programs using six read buffer configurations with varying read buffer sizes. Two alternative configurations are shown to be the most efficient and differed depending on whether split-cycle-saves are assumed. Up to a 55 percent read buffer size reduction is achievable with an average reduction of 39 percent given the most efficient read buffer configuration and a variety of applications.

Alewine, N. J.↗
NASA NTRS2024

SUPIN: A Tool for the Aerodynamic Design and Analysis of Supersonic Inlets

The Supersonic Inlet Design and Analysis Tool (SUPIN) is a computational program that performs geometric modeling and aerodynamic design and analysis of a set of supersonic inlets whose types include the axisymmetric pitot, three-dimensional pitot, axisymmetric, two-dimensional, two-dimensional bifurcated-duct, and streamline-traced inlets. The inlets are modeled by dividing the inlet flowpath into components that start at the freestream and ends at the engine face. The primary components of the inlet include the external supersonic diffuser, throat section, and subsonic diffuser. Each component is characterized by a set of inputs that include geometric and aerodynamic factors. Examples of the geometric factors are angles, lengths, area ratios, and coordinates that describe the geometry of the components. Examples of the aerodynamic factors are Mach numbers, flow ratios, and pressure ratios that set constraints or desired aerodynamic properties of the component. These input factors are specified within a text-based input data file that is read into SUPIN. SUPIN is a Fortran 95 program that performs the inlet design and analysis as a batch or non-interactive process. SUPIN writes output data files describing the inlet geometry and aerodynamic performance. SUPIN uses analytic, empirical, and numerical methods to perform the inlet design and analysis. The inlet geometry is constructed using planar and three-dimensional geometry constructs and is represented by coordinates, angles, areas, profiles, and surfaces. Surfaces are output in the form of a Plot3D surface grid file. SUPIN does have some capability to automatically generate planar and three-dimensional, multi-block, structured grids for computational fluid dynamics (CFD) analysis. The aerodynamic analysis performed by SUPIN computes quasi-one-dimensional properties, such as Mach numbers, pressures, and temperatures, through the inlet flowpath. Planar aerodynamic properties, such as those for shock and Mach waves, are computed for the supersonic compression of the external supersonic diffuser and throat section. The inlet performance is characterized by the inlet flow rates, total pressure recovery, and inlet drag. The primary intent of this document is to describe the usage of SUPIN. The methods used within SUPIN are documented and may serve as a useful reference for understanding the aerodynamic design and analysis of supersonic inlets.

supersonic inlets↗
NASA NTRS1980

Wall proximity corrections for hot-wire readings in turbulent flows

This note describes some details of recent (successful) attempts of wall proximity corrections for hot-wire measurements performed in a three-dimensional incompressible turbulent boundary layer. A simple and quite satisfactory method of estimating wall proximity effects on hot-wire readings is suggested.

Hebbar, K. S.↗
DOE OSTI2019

False positives in PIRADS (V2) 3, 4, and 5 lesions: relationship with reader experience and zonal location

Purpose: To investigate the effect of reader experience and zonal location on the occurrence of false positives (FPs) in PIRADS (V2) 3, 4, and 5 lesions on multiparametric (MP)-MRI of the prostate. Materials and methods: This retrospective study included 139 patients who had consecutively undergone an MP-MRI of the prostate in combination with a transrectal ultrasound MRI fusion-guided biopsy between 2014 and 2017. MRI exams were prospectively read by a group of inexperienced radiologists (cohort 1; 54 patients) and an experienced radiologist (cohort 2; 85 patients). Multivariable logistic regression analysis was performed to determine the association of experience of the radiologist and zonal location with a FP reading. FP rates were compared between readings by inexperienced and experienced radiologists according to zonal location, using Chi-square (χ{sup 2}) tests. Results: A total of 168 lesions in 139 patients were detected. Median patient age was 68 years (Interquartile range (IQR) 62.5–73), and median PSA was 10.9 ng/mL (IQR 7.6–15.9) for the entire patient cohort. According to multivariable logistic regression, inexperience of the radiologist was significantly (P = 0.044, odds ratio 1.927, 95% confidence interval [CI] 1.017–3.651) and independently associated with a FP reading, while zonal location was not (P = 0.202, odds ratio 1.444, 95% CI 0.820–2.539). In the transition zone (TZ), the FP rate of the inexperienced radiologists 59% (17/29) was significantly higher (χ{sup 2}P = 0.033) than that of the experienced radiologist 33% (13/40). Conclusion: Inexperience of the radiologist is significantly and independently associated with a FP reading, while zonal location is not. Inexperienced radiologists have a significantly higher FP rate in the TZ.

62 RADIOLOGY AND NUCLEAR MEDICINE↗