Engineering Papers⌕ Search

SEARCH · Engineering Papers

Results for “DATA ANALYSIS”

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.

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

At least 973 records · Page 54
All sourcesNASA NTRSDOE OSTI
NASA NTRS1995

Estimating errors in least-squares fitting

While least-squares fitting procedures are commonly used in data analysis and are extensively discussed in the literature devoted to this subject, the proper assessment of errors resulting from such fits has received relatively little attention. The present work considers statistical errors in the fitted parameters, as well as in the values of the fitted function itself, resulting from random errors in the data. Expressions are derived for the standard error of the fit, as a function of the independent variable, for the general nonlinear and linear fitting problems. Additionally, closed-form expressions are derived for some examples commonly encountered in the scientific and engineering fields, namely ordinary polynomial and Gaussian fitting functions. These results have direct application to the assessment of the antenna gain and system temperature characteristics, in addition to a broad range of problems in data analysis. The effects of the nature of the data and the choice of fitting function on the ability to accurately model the system under study are discussed, and some general rules are deduced to assist workers intent on maximizing the amount of information obtained form a given set of measurements.

Richter, P. H.↗
NASA NTRS1981

CF 6 engine diagnostics

A summary of the activities which led to defining deterioration rates of the CF6 family of engines, a description of what was learned, and an identification of means of conserving fuel based upon the program findings are presented. The program to define the deterioration levels and modes for the CF6 family of engines involved four distinct phases: analysis of inbound engine test results, analysis of airline cruise data, analysis of airline test cell data resulting from testing of refurbished engines, and inspection of engine hardware.

Stricklin, R.↗
DOE OSTI2025

Calorimeter Pileup Deconvolution for Online Trigger Primitives

In high energy physics experiment, as the luminosity increases, pile-up issues on detectors such as calorimeters become non-negligible. Deconvolution approaches with mathematic pre-assumptions such as Sparse Representation are developed for data analysis stage. For online computation tasks such as for trigger primitive creation, signal availability is significantly different as in offline data analysis stage, and therefore, different (yet simpler) algorithms should be explored. In this document, several approaches of deconvolution suitable for FPGA implementation are discussed.

Wu, Jin-yuan [Fermilab] (ORCID:0000000344329521)↗
NASA NTRS1983

LANDSAT-4 image data quality analysis

Analysis during the quarter was carried out on geometric, radiometric, and information content aspects of both MSS and thematic mapper (TM) data. Test sites in Webster County, Iowa and Chicago, IL., and near Joliet, IL were studied. Band to band registration was evaluated and TM Bands 5 and 7 were found to be approximately 0.5 pixel out of registration with 1,2,3,4, and the thermal was found to be misregistered by 4 30 m pixels to the east and 1 pixel south. Certain MSS bands indicated nominally .25 pixel misregistration. Radiometrically, some striping was observed in TM bands and significant oscillatory noise patterns exist in MSS data which is possibly due to jitter. Information content was compared before and after cubic convolution resampling and no differences were observed in statistics or separability of basic scene classes.

Anuta, P. E.↗
NASA NTRS1986

Interplanetary optical navigation - Voyager Uranus encounter

Optical observations were necessary during the Voyager II Uranus approach and encounter in order to meet mission navigational requirements. In this paper, the overall optical navigation system and operation at Uranus are outlined. The formulation of the optical observables are presented, as well as their subsequent integration into the overall orbit determination products. Optical data analysis and some resulting orbit determination results from Uranus are shown. Certain scientifically important results were natural outcomes of the optical data analysis, and these are also reviewed. Finally, certain optical navigation related problems are anticipated at the forthcoming Neptune encounter in 1989; these are briefly discussed as are plans to deal with them.

Synnott, S. P.↗
NASA NTRS1992

Preliminary calibration results for the BATSE instrument on CGRO

Preliminary results pertaining to spectral reconstruction using Burst and Transient Source (BATSE) Large Area Detector measurements of solar flares are presented. The solar flare measurements are currently being used to fine tune the calibration of our data analysis software. The current status of the stability of spectral analysis, given the systematic errors present in burst location, are given. A brief description is given of enhancements to the input data for the atmospheric scattering algorithm that will be implemented in the data analysis software.

Pendleton, G. N.↗
NASA NTRS1984

Data engineering systems: Computerized modeling and data bank capabilities for engineering analysis

The Data Engineering System (DES) is a computer-based system that organizes technical data and provides automated mechanisms for storage, retrieval, and engineering analysis. The DES combines the benefits of a structured data base system with automated links to large-scale analysis codes. While the DES provides the user with many of the capabilities of a computer-aided design (CAD) system, the systems are actually quite different in several respects. A typical CAD system emphasizes interactive graphics capabilities and organizes data in a manner that optimizes these graphics. On the other hand, the DES is a computer-aided engineering system intended for the engineer who must operationally understand an existing or planned design or who desires to carry out additional technical analysis based on a particular design. The DES emphasizes data retrieval in a form that not only provides the engineer access to search and display the data but also links the data automatically with the computer analysis codes.

Kopp, H.↗
NASA NTRS1998

Examination of two methods for statistical analysis of data with magnitude and direction emphasizing vestibular research applications

When the dependent (or response) variable response variable in an experiment has direction and magnitude, one approach that has been used for statistical analysis involves splitting magnitude and direction and applying univariate statistical techniques to the components. However, such treatment of quantities with direction and magnitude is not justifiable mathematically and can lead to incorrect conclusions about relationships among variables and, as a result, to flawed interpretations. This note discusses a problem with that practice and recommends mathematically correct procedures to be used with dependent variables that have direction and magnitude for 1) computation of mean values, 2) statistical contrasts of and confidence intervals for means, and 3) correlation methods.

Vestibule↗
NASA NTRS1972

An interdisciplinary analysis of ERTS data for Colorado mountain environments using ADP techniques. An early analysis of ERTS-1 data

There are no author-identified significant results in this report. The principal problem encountered has been the lack of good quality, small scale baseline photography for the test areas. Analysis of the ERTS-1 data for the San Juan Site will emphasize development of a preliminary spectral classification defining grass cover categories, and then selection of subframes for intensive investigation of the forestry, geologic, and hydrologic properties of the area. Primary work has been devoted to the selection and digitization of areas for topographic modeling, and compilation of ground based data maps necessary for computer analysis. Study effort has emphasized: geomorphic features; macro-vegetation; micro-vegetation; snow-hydrology; insect/disease damage; and blow-down. Analysis of a frame of the Lake Texoma area indicates a great deal of potential in the analysis and interpretation of ERTS imagery. Preliminary results of investigations of geologic, forest, range, cropland, and water resources of the area are summarized.

Hoffer, R. M.↗
NASA NTRS1995

Global tropospheric experiment at the Hong Kong Atmosphere Chemistry Measurement Station

The major activities of the Global Tropospheric Experiment at the Hong Kong Atmospheric Chemistry Measurement Station are presented for the period 1 January - 31 December 1995. Activities included data analysis, reduction, and archiving of atmospheric measurements and sampling. Sampling included O3, CO, SO2, NO, TSP, RSP, and ozone column density. A data archive was created for the surface meteorological data. Exploratory data analysis was performed, including examination of time series, frequency distributions, diurnal variations and correlation. The major results have been or will be published in scientific journals as well as presented at conferences/workshops. Abstracts are attached.

Carroll, Mary Ann↗
NASA NTRS2001

Preliminary Results From The First Flight of ATIC

The Advanced Thin Ionization Calorimeter (ATIC) instrument is designed to measure the composition and energy spectra of Z = 1 to 28 cosmic rays over the energy range approximately 10 GeV - 100 TeV. The instrument was calibrated in September 1999 at CERN using accelerated electron, proton and pion beams. ATIC was launched as a long duration balloon test flight on 12/28/00 local time from McMurdo, Antarctica. After flying successfully for about 16 days the payload was recovered in excellent condition. Absolute calibration of the detector response was made using cosmic-ray muons. The data analysis algorithm which was developed with Monte Carlo simulations and validated with the CERN beam test will be used for the flight data analysis. Preliminary results of the proton and helium spectra will be reported in this paper.

Seo, E. S.↗
NASA NTRS2001

Preliminary Results From the First Flight of ATIC

The Advanced Thin Ionization Calorimeter (ATIC) instrument is designed to measure the composition C and energy spectra of Z = 1 to 28 cosmic rays over the energy range approximately 10 GeV - 100 TeV. The instrument was calibrated in September 1999 at CERN using accelerated electron, proton and pion beams. ATIC was launched as a long duration balloon test flight on 12/28/00 local time from McMurdo, Antarctica. After flying successfully for about 16 days the payload was recovered in excellent condition. Absolute calibration of the detector response was made using cosmic-ray muons. The data analysis algorithm which was developed with Monte Carlo simulations and validated with the CERN beam test will be used for the flight data analysis. Preliminary results of the protons and C helium spectra will be reported in this paper.

Seo, E. S.↗
NASA NTRS2026

Recommended Practice for Use of ExB Probes in Electric Propulsion Testing

An ExB probe is an electric propulsion plume diagnostic that has at its core a Wien filter. Ions entering the instrument experience perpendicular electric and magnetic fields and are filtered based on their velocity. While the ExB probe can be used to estimate the ion velocity distribution function, in the electric propulsion community, it is commonly used to measure species fractions. There are numerous probe designs, implementation and operation procedures, and data analysis approaches described and in use across the community. This paper provides recommendations and descriptions of best practices for design, implementation, and data analysis for the ExB probe, with a particular emphasis on Hall and ion thrusters. This work contributes to the broader community goal to standardize the use of diagnostics in electric propulsion testing.

ExB probe↗
NASA NTRS1994

Trajectory analysis of Polar Patrol Balloon (PPB) flights in the stratosphere over Antarctica in summer and spring: A preliminary result

Actual trajectories of two PPB's which flew in the Antarctic stratosphere in austral summer and spring are compared with those calculated based on objective analysis data of Japan Meteorological Agency (JMA). The differences between the actual and calculated trajectories are discussed to check reliability of the JMA objective analysis data for the stratosphere, and to detect subsynoptic scale variability due to gravity waves and others.

Kanzawa, Hiroshi↗
DOE OSTI2026

Uncertainty-Aware Machine Learning for Small-Angle X-ray Scattering Analysis in Autonomous Experimentation

Small-angle X-ray scattering (SAXS) is a powerful high-throughput characterization tool for probing nanoscale structure in native sample environments, providing real-time morphological information such as nanoparticle size and shape during synthesis. However, automated SAXS data analysis for extracting meaningful structural parameters is non-trivial and remains a bottleneck in closed-loop experimentation towards autonomous materials discovery, which demands fast, reliable, and uncertainty-aware data analysis. Here, we develop a machine-learning approach for automated SAXS analysis tailored to closed-loop nanoparticle synthesis. A Random Forest (RF) regression model is trained on 100,000 synthetic SAXS curves generated from polydisperse spherical nanoparticles with realistic background contributions. Using normalized one-dimensional SAXS intensity profiles as input, the RF model directly predicts nanoparticle radius, size polydispersity, and background parameters, while the ensemble standard deviation across trees provides built-in uncertainty quantification (UQ). On synthetic data, we show that combining fit-quality metrics (R 2 , MAE) with thresholds on prediction uncertainty reliably identifies accurate parameter estimates without access to ground truth. We then apply the trained model to 365 experimental SAXS profiles of citrate-reduced gold nanoparticles synthesized using an automated droplet-flow microreactor with in situ SAXS at a synchrotron beamline, classifying the results into high- and low-confidence subsets based on UQ metrics. Finally, we integrate RF-based SAXS analysis into a simulated closed-loop optimization campaign using Gaussian process Bayesian optimization to minimize nanoparticle polydispersity, benchmarking against conventional automated Levenberg–Marquardt fitting. The RF-guided campaign exhibits substantially faster convergence and lower relative opportunity cost (∼0.07 vs ∼0.3), demonstrating that uncertainty-aware machine-learning SAXS analysis significantly enhances the efficiency and robustness of autonomous nanomaterials synthesis workflows.

Bayesian optimization↗
NASA NTRS1991

SEAPAK user's guide, version 2.0. Volume 2: Descriptions of programs

The SEAPAK is a user-interactive satellite data analysis package that was developed for the processing and interpretation of Nimbus-7/Coastal Zone Color Scanner (CZCS) and the NOAA Advanced Very High Resolution Radiometer (AVHRR) data. Significant revisions were made since version 1.0, and the ancillary environmental data analysis module was greatly expanded. The package continues to be user friendly and user interactive. Also, because the scientific goals of the ocean color research being conducted have shifted to large space and time scales, batch processing capabilities for both satellite and ancillary environmental data analyses were enhanced, thus allowing for large quantities of data to be ingested and analyzed.

Mcclain, Charles R.↗
DOE OSTI2025

SAXS Assistant: Automated SAXS analysis for structural discovery in biologics and polymeric nanoparticles

Small-angle x-ray scattering (SAXS) is a powerful technique for assessing macromolecular structure. High-throughput SAXS is limited by the time-consuming and, at times, subjective nature of SAXS data interpretation. Here, we present SAXS Assistant, a Python-based script that streamlines SAXS data analysis to extract features for machine learning (ML) and key structural parameters, including the Guinier radius of gyration (R g ), pair distance distribution function (PDDF)-derived R g , maximum particle dimension (D max ), and Kratky plots. The script builds upon BioXTAS RAW and validates reliability via Guinier/PDDF R g agreement, an important indicator of well-measured data sets. For assistance in D max estimation, a multilayer perceptron regressor was trained with 1940 data files from the Small Angle Scattering Biological Data Bank. The model achieved a test set performance R 2 = 0.90 and mean absolute error = 11.7 Å. Training exclusively with experimental data translates analyses from researchers, including experts in the field, to the ML model, which helps assess D max estimations from PDDF. Gaussian mixture model clustering was implemented to classify profiles into structural classes based on entries in the Small Angle Scattering Biological Data Bank. Users may therefore assess the similarity between experimental samples and known biomolecular shapes within the mapped repository entries. This probabilistic clustering aids in quantifying information from Kratky and generating shape-descriptive features. SAXS Assistant accelerates SAXS data analysis through enforced quality control, ML-ready outputs, and flags for low-confidence results. In addition to providing the ability to analyze large data sets at high throughput, this tool is versatile and may serve researchers in both biological and synthetic polymer research fields.

36 MATERIALS SCIENCE↗