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DOE OSTI2021

Analysis of Previously Classified White Dwarf–Main-sequence Binaries Using Data from the APOGEE Survey

We present analyses of near-infrared spectroscopic data from the Apache Point Observatory Galactic Evolution Experiment (APOGEE) survey for 45 previously confirmed or candidate white dwarf–main-sequence (WDMS) binaries identified by the optical Sloan Digital Sky Survey (SDSS) and LAMOST surveys. Among these 45 systems, we classify three as having red giant primaries in the LAMOST sample and 14 as young stellar object contaminants in the photometrically identified SDSS sample. From among the subsample of 28 systems that we confirm to have MS primaries, we derive and place limits on orbital periods and velocity amplitudes for 14. Seven systems have significant velocity variations that warrant a post-common-envelope (PCE) binary classification, four of which are newly classified, three of which are newly confirmed, and five for which we can derive full orbital parameters. If confirmed, one of these newly discovered systems (2M14544500+4626456) will have the second-longest orbital period reported for a typical compact PCE WDMS binary (P = 15.1 days). In addition to the seven above, we also recover and characterize with APOGEE data the well-known PCE WDMS systems EG UMa and HZ 9. We also investigate the overall metallicity distribution of the WDMS sample, which is a parameter space not often explored for these systems. Of note, we find one system (2M14244053+4929580) to be extremely metal-poor ([Fe/H] = − 1.42) relative to the rest of the near-solar sample. Additionally, the PCE systems in our sample are found to be, on average, higher in metallicity than their wide-binary counterparts, though we caution that with this small number of systems, the sample may not be representative of the overall distribution of WDMS systems.

36 MATERIALS SCIENCE↗

NASA NTRS2002

ASPRS Digital Imagery Guideline Image Gallery Discussion

The objectives of the image gallery are to 1) give users and providers a simple means of identifying appropriate imagery for a given application/feature extraction; and 2) define imagery sufficiently to be described in engineering and acquisition terms. This viewgraph presentation includes a discussion of edge response and aliasing for image processing, and a series of images illustrating the effects of signal to noise ratio (SNR) on images. Another series of images illustrates how images are affected by varying the ground sample distances (GSD).

Ryan, Robert↗

DOE OSTI2022

Probing the Galactic halo with RR Lyrae stars – II. The substructures of the Milky Way

ABSTRACT We identify substructures of the Galactic halo using 3003 type ab RR Lyrae stars with six-dimensional position–velocity information from the Sloan Digital Sky Survey, the Large Sky Area Multi-Object Fiber Spectroscopic Telescope and the Gaia Early Data Release 3. Based on this information, we define the separation of any two of the stars in the integrals of motion space and we identify substructures by utilizing the friends-of-friends algorithm. We identify members belonging to several known substructures: the Sagittarius stream, the Gaia-Enceladus-Sausage (GES), the Sequoia and the Helmi streams. In addition to these known substructures, there are three other substructures possibly associated with globular clusters NGC 5272, 6656 and 5024, respectively. Finally, we also find three remaining unknown substructures, one of which has large angular momentum and a mean metallicity −2.13 dex, which may be a new substructure. As for the GES, we find that it accounts for a large part of substructures in the inner halo and the apocentre distance is in the range 10–34 kpc, which suggests that the GES is mainly distributed in the inner halo. The near one-third proportion of the GES and the peak value of 20 kpc of the apocentre distance suggest that the GES could account for the break in the density profile of the Galactic halo at the Galactocentric distance ~20–25 kpc. The similarity when comparing the kinematic properties of the GES with the Hercules–Aquila Cloud and Virgo Overdensity suggests that the three substructures may have similar origins.

79 ASTRONOMY AND ASTROPHYSICS↗

DOE OSTI2022

Automatic detection of low surface brightness galaxies from Sloan Digital Sky Survey images

ABSTRACT Low surface brightness (LSB) galaxies are galaxies with central surface brightness fainter than the night sky. Due to the faint nature of LSB galaxies and the comparable sky background, it is difficult to search LSB galaxies automatically and efficiently from large sky survey. In this study, we established the low surface brightness galaxies autodetect (LSBG-AD) model, which is a data-driven model for end-to-end detection of LSB galaxies from Sloan Digital Sky Survey (SDSS) images. Object-detection techniques based on deep learning are applied to the SDSS field images to identify LSB galaxies and estimate their coordinates at the same time. Applying LSBG-AD to 1120 SDSS images, we detected 1197 LSB galaxy candidates, of which 1081 samples are already known and 116 samples are newly found candidates. The B-band central surface brightness of the candidates searched by the model ranges from 22 to 24 mag arcsec−2, quite consistent with the surface brightness distribution of the standard sample. A total of 96.46 per cent of LSB galaxy candidates have an axial ratio (b/a) greater than 0.3, and 92.04 per cent of them have $fracDev\_r$ < 0.4, which is also consistent with the standard sample. The results show that the LSBG-AD model learns the features of LSB galaxies of the training samples well, and can be used to search LSB galaxies without using photometric parameters. Next, this method will be used to develop efficient algorithms to detect LSB galaxies from massive images of the next-generation observatories.

79 ASTRONOMY AND ASTROPHYSICS↗

NASA NTRS2003

NASA Tech Briefs, July 2003

Topics covered include: Real-Time, High-Frequency QRS Electrocardiograph; Software for Improved Extraction of Data From Tape Storage; Radio System for Locating Emergency Workers; Software for Displaying High-Frequency Test Data; Capacitor-Chain Successive-Approximation ADC; Simpler Alternative to an Optimum FQPSK-B Viterbi Receiver; Multilayer Patch Antenna Surrounded by a Metallic Wall; Software To Secure Distributed Propulsion Simulations; Explicit Pore Pressure Material Model in Carbon-Cloth Phenolic; Meshed-Pumpkin Super-Pressure Balloon Design; Corrosion Inhibitors as Penetrant Dyes for Radiography; Transparent Metal-Salt-Filled Polymeric Radiation Shields; Lightweight Energy Absorbers for Blast Containers; Brush-Wheel Samplers for Planetary Exploration; Dry Process for Making Polyimide/ Carbon-and-Boron-Fiber Tape; Relatively Inexpensive Rapid Prototyping of Small Parts; Magnetic Field Would Reduce Electron Backstreaming in Ion Thrusters; Alternative Electrochemical Systems for Ozonation of Water; Interferometer for Measuring Displacement to Within 20 pm; UV-Enhanced IR Raman System for Identifying Biohazards; Prognostics Methodology for Complex Systems; Algorithms for Haptic Rendering of 3D Objects; Modeling and Control of Aerothermoelastic Effects; Processing Digital Imagery to Enhance Perceptions of Realism; Analysis of Designs of Space Laboratories; Shields for Enhanced Protection Against High-Speed Debris; Study of Dislocation-Ordered In(x)Ga(1-x)As/GaAs Quantum Dots; and Tilt-Sensitivity Analysis for Space Telescopes.

Source record↗

NASA NTRS2016

Optical Evaluation of DMDs with UV-Grade FS, Sapphire, MgF2 Windows and Reflectance of Bare Devices

Digital Micro-mirror Devices (DMDs) have been identified as an alternative to microshutter arrays for space-based multi-object spectrometers (MOS). Specifically, the MOS at the heart of a proposed Galactic Evolution Spectroscopic Explorer (GESE) that uses the DMD as a reprogrammable slit mask. Unfortunately, the protective borosilicate windows limit the use of DMDs in the UV and IR regimes, where the glass has insufficient throughput. In this work, we present our efforts to replace standard DMD windows with custom windows made from UV-grade fused silica, Low Absorption Optical Sapphire (LAOS) and magnesium fluoride. We present reflectance measurements of the antireflection coated windows and a reflectance study of the DMDs active area (window removed). Furthermore, we investigated the long-term stability of the DMD reflectance and recoating device with fresh Al coatings.

Quijada, Manuel A.↗

DOE OSTI2019

The Arecibo Pisces–Perseus Supercluster Survey. I. Harvesting ALFALFA

We report a multi-objective campaign of targeted 21 cm H i line observations of sources selected from the Arecibo Legacy Fast Arecibo L-band Feed Array (ALFALFA) survey and galaxies identified by their morphological and photometric properties in the Sloan Digital Sky Survey. The aims of this program have been (1) to confirm the reality of some ALFALFA sources whose enigmatic nature suggest additional multiwavelength observations; (2) to probe the low signal-to-noise ratio (S/N) regime, below the ALFALFA reliability limit; and (3) to explore the feasibility of using optical morphology, color, and surface brightness to identify gas-rich objects in the region of the Pisces–Perseus Supercluster (PPS) whose H i fluxes are below the ALFALFA sensitivity limit at that distance. As expected, the reliability of ALFALFA detections depends strongly on the S/N of the H i line signal and its coincidence with a probable stellar counterpart identified by its optical properties, suggestive of ongoing star formation. The identification of low-mass, star-forming populations enables targeted H i line observations to detect galaxies with H i line fluxes below the ALFALFA sensitivity limits in fixed local volumes (D < 100 Mpc). The method explored here serves as the basis for extending the sample of gas-bearing objects as part of the ongoing Arecibo Pisces–Perseus Supercluster Survey (APPSS).

79 ASTRONOMY AND ASTROPHYSICS↗

NASA NTRS1994

Locating buildings in aerial photos

Algorithms and techniques for use in the identification and location of large buildings in digitized copies of aerial photographs are developed and tested. The building data would be used in the simulation of objects located in the vicinity of an airport that may be detected by aircraft radar. Two distinct approaches are considered. Most building footprints are rectangular in form. The first approach studied is to search for right-angled corners that characterize rectangular objects and then to connect these corners to complete the building. This problem is difficult because many nonbuilding objects, such as street corners, parking lots, and ballparks often have well defined corners which are often difficult to distinguish from rooftops. Furthermore, rooftops come in a number of shapes, sizes, shadings, and textures which also limit the discrimination task. The strategy used linear sequences of different samples to detect straight edge segments at multiple angles and to determine when these segments meet at approximately right-angles with respect to each other. This technique is effective in locating corners. The test image used has a fairly rectangular block pattern oriented about thirty degrees clockwise from a vertical alignment, and the overall measurement data reflect this. However, this technique does not discriminate between buildings and other objects at an operationally suitable rate. In addition, since multiple paths are tested for each image pixel, this is a time consuming task. The process can be speeded up by preprocessing the image to locate the more optimal sampling paths. The second approach is to rely on a human operator to identify and select the building objects and then to have the computer determine the outline and location of the selected structures. When presented with a copy of a digitized aerial photograph, the operator uses a mouse and cursor to select a target building. After a button on the mouse is pressed, with the cursor fully within the perimeter of the building, the program scans from the position of the cursor to a perimeter position where a shift in grayscale is detected. Once at the perimeter, the process traces along it, around the building, until it eventually returns to the perimeter starting point. Spatial resolution limits cause the perimeter trace to be somewhat course so that a line straightening algorithm is employed. One result is that the building corner positions become more distinctly defined.

Green, James S.↗

NASA NTRS1984

Analysis of the quality of image data acquired by the LANDSAT-4 thematic mapper and multispectral scanners

A seven step procedure developed for evaluating the geometric properties of MSS and TM film produces is being implemented. Some 476 control points were selected of which 238 are being tested and edited for digitization and scaling errors. Tables show statistics established for assessing the spectral characteristics and variability, as well as the spatial resolution and radiometric sensitivity of TM data for a forest environment in an effort to determine the extent to which major forest cover type can be detected and identified on TM digital and image products. Results thus far show that the high quality obtained are more than sufficient for meeting most of the inventory objectives of the renewable resource specialist. The TM data should be extremely valuable for: (1) estimating forest cover types; (2) updating land use survey maps; and (3) determining the size and shape and location of individual forest clearings and water resources.

Colwell, R. N.↗

NASA NTRS1987

Optical and digital pattern recognition; Proceedings of the Meeting, Los Angeles, CA, Jan. 13-15, 1987

The papers presented in this volume provide an overview of current research in both optical and digital pattern recognition, with a theme of identifying overlapping research problems and methodologies. Topics discussed include image analysis and low-level vision, optical system design, object analysis and recognition, real-time hybrid architectures and algorithms, high-level image understanding, and optical matched filter design. Papers are presented on synthetic estimation filters for a control system; white-light correlator character recognition; optical AI architectures for intelligent sensors; interpreting aerial photographs by segmentation and search; and optical information processing using a new photopolymer.

Liu, Hua-Kuang↗

NASA NTRS1993

Application of a Two Camera Video Imaging System to Three-Dimensional Vortex Tracking in the 80- by 120-Foot Wind Tunnel

A description is presented of two enhancements for a two-camera, video imaging system that increase the accuracy and efficiency of the system when applied to the determination of three-dimensional locations of points along a continuous line. These enhancements increase the utility of the system when extracting quantitative data from surface and off-body flow visualizations. The first enhancement utilizes epipolar geometry to resolve the stereo "correspondence" problem. This is the problem of determining, unambiguously, corresponding points in the stereo images of objects that do not have visible reference points. The second enhancement, is a method to automatically identify and trace the core of a vortex in a digital image. This is accomplished by means of an adaptive template matching algorithm. The system was used to determine the trajectory of a vortex generated by the Leading-Edge eXtension (LEX) of a full-scale F/A-18 aircraft tested in the NASA Ames 80- by 120-Foot Wind Tunnel. The system accuracy for resolving the vortex trajectories is estimated to be +/-2 inches over distance of 60 feet. Stereo images of some of the vortex trajectories are presented. The system was also used to determine the point where the LEX vortex "bursts". The vortex burst point locations are compared with those measured in small-scale tests and in flight and found to be in good agreement.

Meyn, Larry A.↗

DOE OSTI2019

Exploring the Psychometrics of Common Post-Scenario Human Factors Questionnaires of Workload, Situation Awareness, and Perceived Difficulty

Abstract: The United States (U.S.) Department of Energy (DOE) Light Water Reactor Sustainability (LWRS) program has the primary mission of sustaining operation of the existing commercial nuclear power plants (NPPs) through a multi-pathway approach in conducting research and development (R&D). In this effort, the role of human factors engineering (HFE) has been an integral in ensuring new digital upgrades that are part of the overall main control room modernization strategy for various U.S. NPPs optimize human-system performance and do not introduce new human failure modes. In this process, testing and evaluation of concept (i.e., prototype) human machine interfaces (HMIs) are done in operator-in-the-loop studies at various stages of the HFE modification process, such as during design and verification and validation (V&V) [1]. During these studies, licensed operators go through select scenarios using a testbed, such as a full-scale simulator or at a NPP’s training simulator, to identify potential usability issues and provide general design feedback regarding the new digital HMIs. Human-system performance is measured and evaluated through a range of objective and self-report measures that capture aspects of plant performance, task performance, workload, situation awareness, and anthropometric and ergonomic concerns [2]. The use of post-scenario questionnaires is an acceptable method for gathering measures of workload and situation awareness. To this end, the NASA-Task Load Index (TLX) [e.g., 3, 4, & 5] and Situation Awareness Rating Technique (SART) [e.g., 6 & 7] are common standardized questionnaires used for evaluating workload and situation awareness, respectively. When combined, these questionnaires consist of a total of 15 questions, each using a different rating scale. Debriefs are also done through interviews with operators to gather design insight after each scenario. Since operator- and training simulator-time is limited, a concern during this post-scenario period of operator-in-the-loop studies is the limited time available to run scenarios, administer post-scenario questionnaires, and debrief within the allotted simulator time. To address this potential problem, this paper explores the psychometric characteristics of NASA-TLX, SART, and a common one-question post-scenario usability questionnaire (i.e., the single ease question – SEQ [8]) in effort to inform future development of a condensed questionnaire that captures aspects of workload and situation awareness. This exploratory work uses data from four different operator-in-the-loop studies completed under prior LWRS operator-in-the-loop studies. Findings from this paper should support future development of a consolidated questionnaire that may be used in operator-in-the-loop studies, when time is compressed, that conforms to the HFE scientific and regulatory requirements set for NPP control room modernization.

99 GENERAL AND MISCELLANEOUS↗

DOE OSTI2024

The VIBES Are Shifting: Assessing Emergent Capabilities in Multi-Modal Models

Researchers assessing open-source domains such as the internet, and particularly those studying information conflict, often have no single prescribed workflow. In the course of their research, they may need to perform a diverse array of tasks far beyond simply identifying an ever-changing set of objects. These analytical tasks can include ascertaining the provenance of images, understand an image in the context of accompanying text-based data, or identifying indicators of digital image manipulation. They must further be able to do this at the scale of tens of thousands of images or more. Traditional machine vision models have typically lacked the flexibility and breadth of performance sufficient for these needs. The research team from Pacific Northwest National Laboratory assessed the performance of a single baseline CLIP ViT-L model against a series of analytical tasks relevant for the study of online information conflict.

97 MATHEMATICS AND COMPUTING↗

NASA NTRS1993

Digital mammography, cancer screening: Factors important for image compression

The use of digital mammography for breast cancer screening poses several novel problems such as development of digital sensors, computer assisted diagnosis (CAD) methods for image noise suppression, enhancement, and pattern recognition, compression algorithms for image storage, transmission, and remote diagnosis. X-ray digital mammography using novel direct digital detection schemes or film digitizers results in large data sets and, therefore, image compression methods will play a significant role in the image processing and analysis by CAD techniques. In view of the extensive compression required, the relative merit of 'virtually lossless' versus lossy methods should be determined. A brief overview is presented here of the developments of digital sensors, CAD, and compression methods currently proposed and tested for mammography. The objective of the NCI/NASA Working Group on Digital Mammography is to stimulate the interest of the image processing and compression scientific community for this medical application and identify possible dual use technologies within the NASA centers.

Clarke, Laurence P.↗

NASA NTRS2012

Wideband Agile Digital Microwave Radiometer

The objectives of this work were to take the initial steps needed to develop a field programmable gate array (FPGA)- based wideband digital radiometer backend (>500 MHz bandwidth) that will enable passive microwave observations with minimal performance degradation in a radiofrequency-interference (RFI)-rich environment. As manmade RF emissions increase over time and fill more of the microwave spectrum, microwave radiometer science applications will be increasingly impacted in a negative way, and the current generation of spaceborne microwave radiometers that use broadband analog back ends will become severely compromised or unusable over an increasing fraction of time on orbit. There is a need to develop a digital radiometer back end that, for each observation period, uses digital signal processing (DSP) algorithms to identify the maximum amount of RFI-free spectrum across the radiometer band to preserve bandwidth to minimize radiometer noise (which is inversely related to the bandwidth). Ultimately, the objective is to incorporate all processing necessary in the back end to take contaminated input spectra and produce a single output value free of manmade signals to minimize data rates for spaceborne radiometer missions. But, to meet these objectives, several intermediate processing algorithms had to be developed, and their performance characterized relative to typical brightness temperature accuracy re quirements for current and future microwave radiometer missions, including those for measuring salinity, soil moisture, and snow pack.

Gaier, Todd C.↗

NASA NTRS1974

Application of ERTS-1 imagery to the study of caribou movements and winter dispersal in relation to prevailing snowcover

The author has identified the following significant results. A multiband classification scheme was applied to ERTS-1 MSS digital tape data in a portion of the Yukon Flats area. Primary analytic objectives of mapping the extent of recent wildfire burns and mature forest were realized illustrating application to moose and caribou biology. Additionally, the analysis indicated the presence of new lakes as well as disappearance of lakes present in 1956. Because this is an important waterfowl production area, similar analyses may have significant application potential to waterfowl biology for rapid updating of habitat information. Further field confirmation of this finding is required.

Lent, P. C.↗

DOE OSTI2019

A Multi-band Catalog of 10978 Star Clusters, Associations, and Candidates in the Milky Way

We present a catalog of Galactic star clusters, associations and candidates with 10978 entries. This multi-band catalog was constructed over 20 years, starting with visual inspections on the Digital Sky Survey and incremented with the 2MASS, WISE, VVV, Spitzer, and Herschel surveys. Large and small catalogs, as well as papers on individual objects have been systematically cross-identified. The catalog provides Galactic and equatorial coordinates, angular diameters, and chronologically ordered designations, making it simple to assign discoveries and verify how often the objects were cataloged by different authors, search methods, and/or surveys. Detection in a single band is the minimum constraint to validate an entry. About 3200 objects have measured parameters in the literature. A fundamental contribution of the present study is to present an additional ≈7700 objects for the first analyses of nature, photometry, spectroscopy and structure. The present focus is not to compile or determine fundamental parameters, but to provide a catalog uniformly characterizing the entries. A major result is that now 4234 embedded clusters are cataloged, a factor of ≈1.5 larger than open clusters. In addition to cross-identifications in different references and wavelength domains, we also communicate the discovery of 638 star clusters and similar objects. The present general catalog provides previously studied objects and thousands of additional entries in a homogeneous way, a timely contribution to Gaia-related works.

79 ASTRONOMY AND ASTROPHYSICS↗

NASA NTRS1974

Triangulation of multistation camera data to locate a curved line in space

A method is described for finding the location of a curved line in space from local azimuth as a function of elevation data obtained at several observation sites. A least-squares criterion is used to insure the best fit to the data. The method is applicable to the triangulation of an object having no identifiable structural features, provided its width is very small compared with its length so as to approximate a line in space. The method was implemented with a digital computer program and was successfully applied to data obtained from photographs of a barium ion cloud which traced out the earth's magnetic field line at very high altitudes.

Fricke, C. L.↗