Data-reduction technique for determining rapidly rising heating rates to thermally thick walls
Aerodynamic heat flux determined within thermally thick walls for case of rapidly rising heat rates
Dillon, J. L.↗
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Observational and Data Reduction Techniques to Optimize Mineralogical Characterizations of Asteroid Surface Materials
Mineralogy is the key to determining the compositional history of the asteroids and to determining the genetic relationships between the asteroids and meteorites. The most sophisticated remote mineralogical characterizations involve the quantitative extraction of specific diagnostic parameters from reflectance spectra and the use of quantitative interpretive calibrations to determine the presence, abundance and/or composition of mineral phases in a surface material. Although this approach is potentially subject to systematic errors, it provides the only consistent set of asteroid surface material characterizations.
Gaffey, M. J.↗
Principal Components as a Data Reduction and Noise Reduction Technique
The potential of principal components as a pipeline data reduction technique for thematic mapper data was assessed and principal components analysis and its transformation as a noise reduction technique was examined. Two primary factors were considered: (1) how might data reduction and noise reduction using the principal components transformation affect the extraction of accurate spectral classifications; and (2) what are the real savings in terms of computer processing and storage costs of using reduced data over the full 7-band TM complement. An area in central Pennsylvania was chosen for a study area. The image data for the project were collected using the Earth Resources Laboratory's thematic mapper simulator (TMS) instrument.
Imhoff, M. L.↗
Unsteady Aerodynamic Testing Using the Dynamic Plunge Pitch and Roll Model Mount
A final report on the DyPPiR tests that were run are presented. Essentially it consists of two parts, a description of the data reduction techniques and the results. The data reduction techniques include three methods that were considered: 1) signal processing of wind on - wind off data; 2) using wind on data in conjunction with accelerometer measurements; and 3) using a dynamic model of the sting to predict the sting oscillations and determining the aerodynamic inputs using an optimization process. After trying all three, we ended up using method 1, mainly because of its simplicity and our confidence in its accuracy. The results section consists of time history plots of the input variables (angle of attack, roll angle, and/or plunge position) and the corresponding time histories of the output variables, C(sub L), C(sub D), C(sub m), C(sub l), C(sub m), C(sub n). Also included are some phase plots of one or more of the output variable vs. an input variable. Typically of interest are pitch moment coefficient vs. angle of attack for an oscillatory motion where the hysteresis loops can be observed. These plots are useful to determine the "more interesting" cases. Samples of the data as it appears on the disk are presented at the end of the report. The last maneuver, a rolling pull up, is indicative of the unique capabilities of the DyPPiR, allowing combinations of motions to be exercised at the same time.
Lutze, Frederick H.↗
Numerical simulations of thermal detection of disbonds in lap joints
A 2D time-dependent FEM heat-transfer algorithm that is unconditionally stable and implicit is presently used to solve for the time-dependence of a structure's temperature. By examining data-reduction techniques in the framework of simulation data, the contrast enhancement afforded by a given technique can be evaluated without regard to experimental error. The present computational simulations demonstrate that the time-derivative technique can clearly delineate the substructure of lap-joint geometries; in addition, histograms of the front surface images are able to quantitatively measure contrast-enhancements for various inspection and data-reduction techniques.
Howell, P. A.↗
Reduction and analysis of data collected during the electromagnetic tornado experiment
Techniques for data processing and analysis are described to support tornado detection by analysis of radio frequency interference in various frequency bands, and sea state determination from short pulse radar measurements. Activities include: strip chart recording of tornado data; the development and implementation of computer programs for digitalization and analysis of the data; data reduction techniques for short pulse radar data, and the simulation of radar returns from the sea surface by computer models.
Davisson, L. D.↗
D-region blunt probe data analysis using hybrid computer techniques
The feasibility of performing data reduction techniques with a hybrid computer was studied. The data was obtained from the flight of a parachute born probe through the D-region of the ionosphere. A presentation of the theory of blunt probe operation is included with emphasis on the equations necessary to perform the analysis. This is followed by a discussion of computer program development. Included in this discussion is a comparison of computer and hand reduction results for the blunt probe launched on 31 January 1972. The comparison showed that it was both feasible and desirable to use the computer for data reduction. The results of computer data reduction performed on flight data acquired from five blunt probes are also presented.
Burkhard, W. J.↗
HPDR: High-Performance Portable Scientific Data Reduction Framework
The rapid growth in scientific data generation is outpacing advancements in computing systems necessary for efficient storage, transfer, and analysis, particularly in the context of exascale computing. With the deployment of first-generation exascale computing systems and next-generation experimental facilities, this gap is widening and necessitates effective data reduction techniques to manage enormous data volumes. Over the past decade, various data reduction methods, including lossless compression, error-controlled lossy compression, and data refactoring, have been developed to accelerate I/O in scientific workflows. Despite significant reductions in data volume, these methods introduce considerable computational overhead, which can become the new bottleneck in data processing. To mitigate this, GPU-accelerated data reduction algorithms have been introduced. However, challenges remain in their integration into exascale workflows, including limited portability across different GPU architectures, substantial memory transfer overhead, and reduced scalability on dense multi-GPU systems. To address these challenges, we propose HPDR, a high-performance and portable data reduction framework. HPDR is designed to enable the execution of state-of-the-art reduction algorithms across diverse processor architectures while reducing memory transfer overhead to 2.3 % of the original, resulting in up to 3.5× faster throughput compared to existing solutions. It also achieves up to 96% of the theoretical speedup in multi-GPU settings. In addition, evaluations on accelerating I/O operations at scale up to 1,024 nodes of the Frontier supercomputer demonstrate that HPDR can achieve up to 103 TB/s reduction throughput, providing up to 4× acceleration in parallel I/O performance compared to existing data reduction routines. This work highlights the potential of HPDR to significantly enhance data reduction efficiency in exascale computing environments.
Chen, Jieyang [University of Oregon]↗
Strain Gauge Balance Calibration and Data Reduction at NASA Langley Research Center
This paper will cover the standard force balance calibration and data reduction techniques used at Langley Research Center. It will cover balance axes definition, balance type, calibration instrumentation, traceability of standards to NIST, calibration loading procedures, balance calibration mathematical model, calibration data reduction techniques, balance accuracy reporting, and calibration frequency.
Ferris, A. T. Judy↗
The overlapping plate method for asteroid astronomy
The overlapping plate method, first introduced in the early 1960s by Henrich Eichhorn, was originally intended to provide better star catalogs through improved data reduction techniques.
astrometry asteroids data reduction techniques↗
Initial OSSE Sky Survey Observation: Deep Survey in the Virgo Region
The OSSE Virgo survey covered about 1% of the sky, using eight weeks of observing time on the Compton Gamma Ray Observatory, and was performed in conjunction with the EGRET and COMPTEL instruments on CGRO. A fundamental aspect of the survey was the development of data reduction techniques for the scanning data from the OSSE detectors. A direct algebraic approach for spatially deconvolving the data was developed. For the survey work, no background observations isolated from the survey region were acquired, unlike normal discrete source observations. The survey, reduction method covers the mapped region with a grid of pixels, and estimates the flux from each pixel by least-squares agreement with the data, assuming positivity constraints. This technique has led to the detection of compact sources at hard X-ray energies within the Virgo region, and the OSSE survey studies have been extended to the south galactic pole and north Ecliptic pole, with similar analysis techniques.
Cameron, Robert↗
Instrumentation, techniques and data reduction associated with airfoil testing programs at Wichita State University
Two dimensional airfoil testing was conducted at the Wichita State University Beech Wind Tunnel for a number of years. The instrumentation developed and adapted during this period of testing for determination of flow fields along with traversing mechanisms for these probes are discussed. In addition, some of the techniques used to account for interference effects associated with the apparatus used for this two dimensional testing are presented. The application of a minicomputer to the data reduction and presentation is discussed.
Rodgers, E. J.↗
The Celescope survey and the galactic distribution of interstellar absorption
The instrumentation and data-reduction techniques used in the Celescope experiment conducted on board OAO-2 are reviewed. A brief summary is presented of the principles of UV astronomy, the Celescope optical package and bay E4 electronic module assembly are described, and the distribution of the Celescope pictures is plotted in galactic coordinates. Described data-reduction techniques include the determination of the U-B and B-V colors, removal of interstellar extinction effects, and construction of model atmospheres for the observed stars. Some difficulties and apparent contradictions encountered in the data interpretation are noted.
Davis, R. J.↗
Optimum radars and filters for the passive sphere system
Studies have been conducted to determine the influence of the tracking radar and data reduction technique on the accuracy of the meteorological measurements made in the 30 to 100 kilometer altitude region by the ROBIN passive falling sphere. A survey of accuracy requirements was made of agencies interested in data from this region of the atmosphere. In light of these requirements, various types of radars were evaluated to determine the tracking system most applicable to the ROBIN, and methods were developed to compute the errors in wind and density that arise from noise errors in the radar supplied data. The effects of launch conditions on the measurements were also examined. Conclusions and recommendations have been made concerning the optimum tracking and data reduction techniques for the ROBIN falling sphere system.
Luers, J. K.↗
CCD surface photometry of galaxies
We present here the results based on analysis of broad band optical images of radio loud and radio quiet galaxies selected from a set of x-ray galaxies. Data reduction techniques, and surface photometry using the IRAF data reduction package are described. The radial surface brightness profile of each galaxy is obtained. The disc, bulge, and nucleus of the galaxy are modeled based on the estimated brightness profile. The model of the galaxy is constructed, which is subtracted from the observed image to enhance the small scale features in the galaxy. Color maps of the galaxy are obtained and compared with those of normal galaxies. The optical properties of the galaxy are compared with its x-ray and radio properties.
Anupama, G. C.↗
Machine Learning Techniques for Data Reduction of Climate Applications
Scientists conduct large-scale simulations to compute derived quantities-of-interest (QoI) from primary data. Often, QoI are linked to specific features, regions, or time intervals, such that data can be adaptively reduced without compromising the integrity of QoI. For many spatiotemporal applications, these QoI are binary in nature and represent presence or absence of a physical phenomenon. We present a pipelined compression approach that first uses neural-network-based techniques to derive regions where QoI are highly likely to be present. Then, we employ a Guaranteed Autoencoder (GAE) to compress data with differential error bounds. GAE uses QoI information to apply low-error compression to only these regions. This results in overall high compression ratios while still achieving downstream goals of simulation or data collections. Experimental results are presented for climate data generated from the E3SM Simulation model for downstream quantities such as tropical cyclone and atmospheric river detection and tracking. These results show that our approach is superior to comparable methods in the literature.
Li, Xiao [University of Florida]↗
Automated Reduction of Data from Images and Holograms
Laser techniques are widely used for the diagnostics of aerodynamic flow and particle fields. The storage capability of holograms has made this technique an even more powerful. Over 60 researchers in the field of holography, particle sizing and image processing convened to discuss these topics. The research program of ten government laboratories, several universities, industry and foreign countries were presented. A number of papers on holographic interferometry with applications to fluid mechanics were given. Several papers on combustion and particle sizing, speckle velocimetry and speckle interferometry were given. A session on image processing and automated fringe data reduction techniques and the type of facilities for fringe reduction was held.
Lee, G.↗
Spectroscopic observations of winds on Venus. I - Technique and data reduction
Methods of measurement and reduction of high-dispersion photographic spectra of Venus are presented. Preliminary results are consistent with slow direct or no rotation at the level sample, and disagree strongly with a 4-day retrograde rotation. A serious systematic error, which affects much published work, is due to blending of solar lines in the sky with those reflected from the planet. This always tends to produce a spurious retrograde 'rotation'. Only data obtained in a dark sky, or daytime observations from which the sky lines have been accurately subtracted, can be relied upon. All such data give low wind speeds.
Young, A. T.↗