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All sourcesNASA NTRSDOE OSTI
NASA NTRSDate not supplied

Operational and Archive Data Records: Surface Elevation Measurements of Lakes, Wetlands, and Rivers for Resources and Hazards

A NASA/USDA funded program offers satellite-derived products for lakes, reservoirs, river reaches, and wetland zones. These are currently being derived from the 10-day and monthly-resolution radar altimeter series. However, observational parameters from the laser based ICESat-2 mission, and the enhanced SWOT KaRIn instrument will also be integrated to meet various end user requirements. The resulting measurements will ultimately be a combination of surface water level and slope, surface water extent, water storage and basin bathymetry, plus a suite of Status Indicators which highlight deviations from long-term and seasonal averages. The main stakeholders are the USDA/Foreign Agricultural Service, the US Geological Survey, USACE/NGA, and various Wetland-related organizations. Applications centre on water and energy resources and fish-catch potential, and on natural hazards (floods and droughts). There is a demand for a global monitoring service, but primary focus is on regions where gauge measurement access is restricted or delayed, or where gauge deployment is hazardous. Ongoing surface acquisition checks and feedback to CNES focusses on the success or failure of the on-board DEM’s on a case-by-case basis. Multiple projects are also underway to improve the surface elevations measurements and the along track resolution (minimum water body width) via exploration of the high resolution (Doppler) Range estimates, the FF-SAR technique, and the high- resolution radiometer based wet tropospheric correction. And while Level3+4 surface water products are being directed by end user requirements, the overriding NASA objectives are the formation of high quality Earth Data Records with high accuracy and uniformity across multiple decades.

Lakes↗
NASA NTRS1998

Enhancing Global Competitiveness: Benchmarking Airline Operational Performance in Highly Regulated Environments

Enhancing competitiveness in the global airline industry is at the forefront of attention with airlines, government, and the flying public. The seemingly unchecked growth of major airline alliances is heralded as an enhancement to global competition. However, like many mega-conglomerates, mega-airlines will face complications driven by size regardless of the many recitations of enhanced efficiency. Outlined herein is a conceptual model to serve as a decision tool for policy-makers, managers, and consumers of airline services. This model is developed using public data for the United States (U.S.) major airline industry available from the U/S. Department of Transportation, Federal Aviation Administration, the National Aeronautics and Space Administration, the National Transportation Safety Board, and other public and private sector sources. Data points include number of accidents, pilot deviations, operational performance indicators, flight problems, and other factors. Data from these sources provide opportunity to develop a model based on a complex dot product equation of two vectors. A row vector is weighted for importance by a key informant panel of government, industry, and consumer experts, while a column vector is established with the factor value. The resulting equation, known as the national Airline Quality Rating (AQR), where Q is quality, C is weight, and V is the value of the variables, is stated Q=C[i1-19] x V[i1-19]. Looking at historical patterns of AQR results provides the basis for establishment of an industry benchmark for the purpose of enhancing airline operational performance. A 7 year average of overall operational performance provides the resulting benchmark indicator. Applications from this example can be applied to the many competitive environments of the global industry and assist policy-makers faced with rapidly changing regulatory challenges.

Bowen, Brent D.↗
NASA NTRS2008

Statistical Short-Range Guidance for Peak Wind Speed Forecasts at Edwards Air Force Base, CA

The peak winds near the surface are an important forecast element for Space Shuttle landings. As defined in the Shuttle Flight Rules (FRs), there are peak wind thresholds that cannot be exceeded in order to ensure the safety of the shuttle during landing operations. The National Weather Service Spaceflight Meteorology Group (SMG) is responsible for weather forecasts for all shuttle landings. They indicate peak winds are a challenging parameter to forecast. To alleviate the difficulty in making such wind forecasts, the Applied Meteorology Unit (AMTJ) developed a personal computer based graphical user interface (GUI) for displaying peak wind climatology and probabilities of exceeding peak-wind thresholds for the Shuttle Landing Facility (SLF) at Kennedy Space Center. However, the shuttle must land at Edwards Air Force Base (EAFB) in southern California when weather conditions at Kennedy Space Center in Florida are not acceptable, so SMG forecasters requested that a similar tool be developed for EAFB. Marshall Space Flight Center (MSFC) personnel archived and performed quality control of 2-minute average and 10-minute peak wind speeds at each tower adjacent to the main runway at EAFB from 1997- 2004. They calculated wind climatologies and probabilities of average peak wind occurrence based on the average speed. The climatologies were calculated for each tower and month, and were stratified by hour, direction, and direction/hour. For the probabilities of peak wind occurrence, MSFC calculated empirical and modeled probabilities of meeting or exceeding specific 10-minute peak wind speeds using probability density functions. The AMU obtained and reformatted the data into Microsoft Excel PivotTables, which allows users to display different values with point-click-drag techniques. The GUT was then created from the PivotTables using Visual Basic for Applications code. The GUI is run through a macro within Microsoft Excel and allows forecasters to quickly display and interpret peak wind climatology and likelihoods in a fast-paced operational environment. A summary of how the peak wind climatologies and probabilities were created and an overview of the GUT will be presented.

Dreher, Joseph↗
NASA NTRS1999

Space-to-Space Communications System

The Space-to-Space Communications System (SSCS) is an Ultra High Frequency (UHF) Time-Division-Multiple Access (TDMA) system that is designed, developed, and deployed by the NASA Johnson Space Center (JSC) to provide voice, commands, telemetry and data services in close proximity among three space elements: International Space Station (ISS), Space Shuttle Orbiter, and Extravehicular Mobility Units (EMU). The SSCS consists of a family of three radios which are, Space-to-Space Station Radio (SSSR), Space-to-Space Orbiter Radio (SSOR), and Space-to-Space Extravehicular Mobility Radio (SSER). The SSCS can support up to five such radios at a time. Each user has its own time slot within which to transmit voice and data. Continuous Phase Frequency Shift Keying (CPFSK) carrier modulation with a burst data rate of 695 kbps and a frequency deviation of 486.5 kHz is employed by the system. Reed-Solomon (R-S) coding is also adopted to ensure data quality. In this paper, the SSCS system requirements, operational scenario, detailed system architecture and parameters, link acquisition strategy, and link performance analysis will be presented and discussed

Kwei tU↗
NASA NTRSDate not supplied

Advances to a Global Agroclimatology Solar Insolation and Meteorological Parameter Data Base: Improved Solar Irradiance up to Hourly Temporal Resolution

A primary objective of NASA’s Prediction of Worldwide Energy Resource (POWER) project is to facilitate the use of NASA Earth Science data holdings within the energy, agricultural, and architectural industries. To this end daily averaged solar data from several NASA projects and metrological data from a NASA assimilation model have long been reformatted and via a user friendly web based data portal (https://power.larc.nasa.gov) at the native resolution of each data products. Potential users can access solar and metrological data in a column formatted DSSAT ASCII format by entering single site specific coordinates or from an area by entering the appropriate area coordinates. Upgrades to the POWER data portal have been implemented that result in a complete upgrade of the base solar insolation data products. From the years 1984 through 2000, a new version of the NASA/GEWEX Surface Radiation Budget (SRB) and Clouds is utilized that reduces the RMS relative to surface measurements. Additionally, Clouds and the Earth’s Radiant Energy System (CERES) SYNoptic 1x1 Degree (SYN1Deg) data products are utilized starting from January 1, 2001 through 3 months of real-time. The CERES Fast Longwave and SHortwave radiative Fluxes (FLASHFlux) is still used to provided daily data spanning from the end of SYN1Deg to within 7 days of real-time. Meteorological parameters now are taken from the NASA Modern Era Retrospective-analysis for Research and Applications (MERRA-2) data set which provides higher resolution data products (hourly and 0.5 x 625 degree) covering the entire globe. Besides updating the solar and meteorological data products, this new version features new data products such as photosynthetically active radiation (PAR), more cloud information, estimates of soil temperatures and improved options for long-term climatological data requests. More than 36+ years daily time slices are included in the combined solar and meteorological data sets. However, perhaps the most important innovation of the POWER GIS-enabled Web Services is the provision of hourly solar and meteorological data products beginning in Jan 1, 2001. The hourly values will enable more detailed modeling and crop analysis that incorporates the diurnal variability of these parameters. The new capability is made possible by utilizing both the CERES SYN1Deg and MERRA-2 data products that include parameters at these resolutions. An assessment of both the meteorological and the solar irradiance data are based upon comparisons with globally distributed surface observations. The meteorological observations from the National Center for Environmental Information’s “Integrated Surface Database” as well as the “Global Summary of the Day” (GSOD) data files. The estimates of solar insolation are compared to the Baseline Solar Radiation Network (BSRN) and other high quality surface measurement networks. Results from the uncertainty assessments demonstrates that the NASA’s meteorological and solar irradiance data can represent a viable alternative to surface observations, particularly in data sparse regions of the world.

solar irradiance↗
NASA NTRS2005

AIRSAR Automated Web-based Data Processing and Distribution System

In this paper, we present an integrated, end-to-end synthetic aperture radar (SAR) processing system that accepts data processing requests, submits processing jobs, performs quality analysis, delivers and archives processed data. This fully automated SAR processing system utilizes database and internet/intranet web technologies to allow external users to browse and submit data processing requests and receive processed data. It is a cost-effective way to manage a robust SAR processing and archival system. The integration of these functions has reduced operator errors and increased processor throughput dramatically.

WEB SERVICES↗
NASA NTRS2002

Monitoring the Microgravity Environment Quality On-board the International Space Station Using Soft Computing Techniques: Preliminary System Performance Results - Part 2

This paper presents the preliminary performance results of the artificial intelligence monitoring system in full operational mode using near real time acceleration data downlinked from the International Space Station. Preliminary microgravity environment characterization analysis result for the International Space Station (Increment-2), using the monitoring system is presented. Also, comparison between the system predicted performance based on ground test data for the US laboratory "Destiny" module and actual on-orbit performance, using measured acceleration data from the U.S. laboratory module of the International Space Station is presented. Finally, preliminary on-orbit disturbance magnitude levels are presented for the Experiment of Physics of Colloids in Space, which are compared with on ground test data. The ground test data for the Experiment of Physics of Colloids in Space were acquired from the Microgravity Emission Laboratory, located at the NASA Glenn Research Center, Cleveland, Ohio. The artificial intelligence was developed by the NASA Glenn Principal Investigator Microgravity Services Project to help the principal investigator teams identify the primary vibratory disturbance sources that are active, at any moment of time, on-board the International Space Station, which might impact the microgravity environment their experiments are exposed to. From the Principal Investigator Microgravity Services' web site, the principal investigator teams can monitor via a dynamic graphical display, implemented in Java, in near real time, which event(s) is/are on, such as crew activities, pumps, fans, centrifuges, compressor, crew exercise, structural modes, etc., and decide whether or not to run their experiments, whenever that is an option, based on the acceleration magnitude and frequency sensitivity associated with that experiment. This monitoring system detects primarily the vibratory disturbance sources. The system has built-in capability to detect both known and unknown vibratory disturbance sources. Several soft computing techniques such as Kohonen's Self-Organizing Feature Map, Learning Vector Quantization, Back-Propagation Neural Networks, and Fuzzy Logic were used to design the system.

Jules, Kenol↗
DOE OSTI2023

Building 438 Drainage Channel Soil Sampling and Analysis Plan (February 2023)

This Soil Sampling and Analysis Plan (SAP) was prepared by the Environmental Function Area (EFA)/Technical Services Department (TSD) of the Environment, Safety & Health (ES&H) Directorate for the Project Management Office (PMO) for the proposed Building 438 Drainage Channel Project (project) located near Building 438 (B438) in the southern portion, Building 433 (B433) in the middle portion, and Building 543 (B543) in the northern portion (project area as shown on Figure 1). The purpose of the SAP was to describe the procedures for collection and analysis of environmental samples and evaluation of analytical data (chemical and radiological) to determine management options of excavated soil during project construction in accordance with Lawrence Livermore National Laboratory’s (LLNL) Soils Screening and Management Plan (SSMP) (LLNL 2022), which is consistent with U.S. Environmental Protection Agency (EPA) guidance for developing Data Quality Objectives for environmental data (EPA 2006). The SAP was developed in accordance with the SSMP and based on preliminary design information provided to EFA by PMO.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2024

Comparative Performance of Three Eye-Tracking Devices in Detection of Mild Traumatic Brain Injury in Acute Versus Chronic Subject Populations

ABSTRACT Introduction Presently, traumatic brain injury (TBI) triage in field settings relies on symptom-based screening tools such as the updated Military Acute Concussion Evaluation. Objective eye-tracking may provide an alternative means of neurotrauma screening due to sensitivity to neurotrauma brain-health changes. Previously, the US Army Medical Research and Development Command Non-Invasive NeuroAssessment Devices (NINAD) Integrated Product Team identified 3 commercially available eye-tracking devices (SyncThink EYE-SYNC, Oculogica EyeBOX, NeuroKinetics IPAS) as meeting criteria toward being operationally effective in the detection of TBI in service members. We compared these devices to assess their relative performance in the classification of mild traumatic brain injury (mTBI) subjects versus normal healthy controls. Materials and Methods Participants 18 to 45 years of age were assigned to Acute mTBI, Chronic mTBI, or Control group per study criteria. Each completed a TBI assessment protocol with all 3 devices counterbalanced across participants. Acute mTBI participants were tested within 72 hours following injury whereas time since last injury for the Chronic mTBI group ranged from months to years. Discriminant analysis was undertaken to determine device classification performance in separating TBI subjects from controls. Area Under the Curves (AUCs) were calculated and used to compare the accuracy of device performance. Device-related factors including data quality, the need to repeat tests, and technical issues experienced were aggregated for reporting. Results A total of 63 participants were recruited as Acute mTBI subjects, 34 as Chronic mTBI subjects, and 119 participants without history of TBI as controls. To maximize outcomes, poorer quality data were excluded from analysis using specific criteria where possible. Final analysis utilized 49 (43 male/6 female, mean [x̅] age = 24.3 years, SD [s] = 5.1) Acute mTBI subjects, and 34 (33 male/1 female, x̅ age = 38.8 years, s = 3.9) Chronic mTBI subjects were age- and gender-matched as closely as possible with Control subjects. AUCs obtained with 80% of total dataset ranged from 0.690 to 0.950 for the Acute Group and from 0.753 to 0.811 for the Chronic mTBI group. Validation with the remaining 20% of dataset produced AUCs ranging from 0.600 to 0.750 for Acute mTBI group and 0.490 to 0.571 for the Chronic mTBI group. Conclusions Potential eye-tracking detection of mTBI, per training model outcomes, ranged from acceptable to excellent for the Acute mTBI group; however, it was less consistent for the Chronic mTBI group. The self-imposed targeted performance (AUC of 0.850) appears achievable, but further device improvements and research are necessary. Discriminant analysis models differed for the Acute versus Chronic mTBI groups, suggesting performance differences in eye-tracking. Although eye-tracking demonstrated sensitivity in the Chronic group, a more rigorous and/or longitudinal study design is required to evaluate this observation. mTBI injuries were not controlled for this study, potentially reducing eye-tracking assessment sensitivity. Overall, these findings indicate that while eye-tracking remains a viable means of mTBI screening, device-specific variability in data quality, length of testing, and ease of use must be addressed to achieve NINAD objectives and DoD implementation.

General & Internal Medicine↗
NASA NTRS1985

Engineering calculations for communications satellite systems planning

Computer-based techniques for optimizing communications-satellite orbit and frequency assignments are discussed. A gradient-search code was tested against a BSS scenario derived from the RARC-83 data. Improvement was obtained, but each iteration requires about 50 minutes of IBM-3081 CPU time. Gradient-search experiments on a small FSS test problem, consisting of a single service area served by 8 satellites, showed quickest convergence when the satellites were all initially placed near the center of the available orbital arc with moderate spacing. A transformation technique is proposed for investigating the surface topography of the objective function used in the gradient-search method. A new synthesis approach is based on transforming single-entry interference constraints into corresponding constraints on satellite spacings. These constraints are used with linear objective functions to formulate the co-channel orbital assignment task as a linear-programming (LP) problem or mixed integer programming (MIP) problem. Globally optimal solutions are always found with the MIP problems, but not necessarily with the LP problems. The MIP solutions can be used to evaluate the quality of the LP solutions. The initial results are very encouraging.

Reilly, C. H.↗
NASA NTRS1992

Exploratory study on performance measures as indicators of IS effectiveness

The Information Systems Directorate at JSC/NASA has undertaken the reevaluation of its performance measures process and measures. Under the direction of a quality approach it is essential to identify an external perspective of how well an organization is performing. This study was conducted with two major objectives: (1) survey and summarize the academic literature on performance measures as indicators of information systems (IS) effectiveness; and (2) survey organizations for their experience in measuring for IS effectiveness. Four approaches to measuring the effectiveness of IS performance were identified: (1) listen to the customer for the things they need; (2) align with corporate goals; (3) benchmark against well-respected organizations; and (4) ask yourself what critical factors lead to success. The list of known methods for soliciting customer feedback are as follows: (1) executive visit; (2) survey, interview, and focus group; (3) complaints and compliments; and (4) service level agreements. A common set of characteristics that satisfy customers was identified from the literature. The list includes elements such as the following: accuracy, timeliness, relevance, understandability, reliability, and completeness. Future research in this topic area should prove beneficial to determine the metrics for external validity.

Bishop, Peter C.↗
NASA NTRS2004

NASA Glenn's Acoustical Testing Laboratory Awarded Accreditation by the National Voluntary Laboratory Accreditation Program

NASA Glenn Research Center's Acoustical Testing Laboratory (ATL) provides a comprehensive array of acoustical testing services, including sound pressure level, sound intensity level, and sound-power-level testing per International Standards Organization (ISO)1 3744. Since its establishment in September 2000, the ATL has provided acoustic emission testing and noise control services for a variety of customers, particularly microgravity space flight hardware that must meet International Space Station acoustic emission requirements. The ATL consists of a 23- by 27- by 20-ft (height) convertible hemi/anechoic test chamber and a separate sound-attenuating test support enclosure. The ATL employs a personal-computer-based data acquisition system that provides up to 26 channels of simultaneous data acquisition with real-time analysis (ref. 4). Specialized diagnostic tools, including a scanning sound-intensity system, allow the ATL's technical staff to support its clients' aggressive low-noise design efforts to meet the space station's acoustic emission requirement. From its inception, the ATL has pursued the goal of developing a comprehensive ISO 17025-compliant quality program that would incorporate Glenn's existing ISO 9000 quality system policies as well as ATL-specific technical policies and procedures. In March 2003, the ATL quality program was awarded accreditation by the National Voluntary Laboratory Accreditation Program (NVLAP) for sound-power-level testing in accordance with ISO 3744. The NVLAP program is administered by the National Institutes of Standards and Technology (NIST) of the U.S. Department of Commerce and provides third-party accreditation for testing and calibration laboratories. There are currently 24 NVLAP-accredited acoustical testing laboratories in the United States. NVLAP accreditation covering one or more specific testing procedures conducted in accordance with established test standards is awarded upon successful completion of an intensive onsite assessment that includes proficiency testing and documentation review. The ATL NVLAP accreditation currently applies specifically to its ISO 3744 soundpower- level determination procedure (see the photograph) and supporting ISO 17025 quality system, although all ATL operations are conducted in accordance with its quality system. The ATL staff is currently developing additional procedures to adapt this quality system to the testing of space flight hardware in accordance with International Space Station acoustic emission requirements.<

Akers, James C.↗
NASA NTRS2008

Precision Cleaning - Path to Premier

ITT Space Systems Division s new Precision Cleaning facility provides critical cleaning and packaging of aerospace flight hardware and optical payloads to meet customer performance requirements. The Precision Cleaning Path to Premier Project was a 2007 capital project and is a key element in the approved Premier Resource Management - Integrated Supply Chain Footprint Optimization Project. Formerly precision cleaning was located offsite in a leased building. A new facility equipped with modern precision cleaning equipment including advanced process analytical technology and improved capabilities was designed and built after outsourcing solutions were investigated and found lacking in ability to meet quality specifications and schedule needs. SSD cleans parts that can range in size from a single threaded fastener all the way up to large composite structures. Materials that can be processed include optics, composites, metals and various high performance coatings. We are required to provide verification to our customers that we have met their particulate and molecular cleanliness requirements and we have that analytical capability in this new facility. The new facility footprint is approximately half the size of the former leased operation and provides double the amount of throughput. Process improvements and new cleaning equipment are projected to increase 1st pass yield from 78% to 98% avoiding $300K+/yr in rework costs. Cost avoidance of $350K/yr will result from elimination of rent, IT services, transportation, and decreased utility costs. Savings due to reduced staff expected to net $4-500K/yr.

Mackler, Scott E.↗
NASA NTRS2012

Efforts to Reduce International Space Station Crew Maintenance Time in the Management of the Extravehicular Mobility Unit Transport Loop Water Quality

The EMU (Extravehicular Mobility Unit) contains a semi-closed-loop re-circulating water circuit (Transport Loop) to absorb heat into a LCVG (Liquid Coolant and Ventilation Garment) worn by the astronaut. A second, single-pass water circuit (Feed-water Loop) provides water to a cooling device (Sublimator) containing porous plates, and that water sublimates through the porous plates to space vacuum. The cooling effect from the sublimation of this water translates to a cooling of the LCVG water that circulates through the Sublimator. The quality of the EMU Transport Loop water is maintained through the use of a water processing kit (ALCLR - Airlock Cooling Loop Remediation) that is used to periodically clean and disinfect the water circuit. Opportunities to reduce crew time associated with ALCLR operations include a detailed review of the historical water quality data for evidence to support an extension to the implementation cycle. Furthermore, an EMU returned after 2-years of use on the ISS (International Space Station) is being used as a test bed to evaluate the results of extended and repeated ALCLR implementation cycles. Finally, design, use and on-orbit location enhancements to the ALCLR kit components are being considered to allow the implementation cycle to occur in parallel with other EMU maintenance and check-out activities, and to extend the life of the ALCLR kit components. These efforts are undertaken to reduce the crew-time and logistics burdens for the EMU, while ensuring the long-term health of the EMU water circuits for a post- Shuttle 6-year service life.

Etter,David↗
NASA NTRS1986

Technology and the Hubble Space Telescope

The components of the Hubble Space Telescope which is a 13.1 m long, 4.27 m in diameter, and weighs 11,000 kg are described. The telescope will be placed in a 600-km circular orbit of 28.5 deg inclination and it has an expected service life of 15 years. The optical telescope assembly contains the hyperbolic Ritchey-Chretin type primary and secondary mirrors and the optical control system. The telescope is to have a field of view of 28 arcmin in diameter. The use of the fine guidance sensors for pointing stability is examined. The optical and scientific system of the telescope are contained in the support system module. A wide-field/planetary camera, ESA-furnished faint object camera, the high-speed photometer, faint-object spectrograph, high resolution spectrograph, and ESA-furnished solar arrays are located on the telescope. The maintenance and refurbishment of the telescope are discussed. The precise lambda/20 optics, stringent cleanliness, and stable pointing of the telescope produce good image quality for astronomical and solar system science studies.

Mitchell, R. E.↗
NASA NTRS2013

Efforts to Reduce International Space Station Crew Maintenance for the Management of the Extravehicular Mobility Unit Transport Loop Water Quality

The EMU (Extravehicular Mobility Unit) contains a semi-closed-loop re-circulating water circuit (Transport Loop) to absorb heat into a LCVG (Liquid Coolant and Ventilation Garment) worn by the astronaut. A second, single-pass water circuit (Feed-water Loop) provides water to a cooling device (Sublimator) containing porous plates, and that water sublimates through the porous plates to space vacuum. The cooling effect from the sublimation of this water translates to a cooling of the LCVG water that circulates through the Sublimator. The quality of the EMU Transport Loop water is maintained through the use of a water processing kit (ALCLR Airlock Cooling Loop Remediation) that is used to periodically clean and disinfect the water circuit. Opportunities to reduce crew time associated with on-orbit ALCLR operations include a detailed review of the historical water quality data for evidence to support an extension to the implementation cycle. Furthermore, an EMU returned after 2-years of use on the ISS (International Space Station) is being used as a test bed to evaluate the results of extended and repeated ALCLR implementation cycles. Finally, design, use and on-orbit location enhancements to the ALCLR kit components are being considered to allow the implementation cycle to occur in parallel with other EMU maintenance and check-out activities, and to extend the life of the ALCLR kit components. These efforts are undertaken to reduce the crew-time and logistics burdens for the EMU, while ensuring the long-term health of the EMU water circuits for a post-Shuttle 6-year service life.

Steele, John W.↗
NASA NTRS2018

Challenges in Development of Online Visualization and Analysis Tools for Satellite Data

Over the years, various online visualization and analysis tools have been developed to facilitate satellite data access and help scientific users around the world to conduct research and develop applications (e.g., data product evaluation, what-if questions, etc.). For those who are new to satellite data products, using them can be a daunting task due to many obstacles in data processing such as data formats, complex data structures, special software packages, unfamiliar terminology, etc., especially when one is not sure whether a dataset is suitable for his/er research project. Even for experienced users, developing software for data processing and analysis can be a costly and time-consuming task. Online visualization tools can overcome many of these difficulties and allow users to focus on scientific questions. For example, Giovanni (the Geospatial Interactive Online Visualization and Analysis Infrastructure, https://giovanni.gsfc.nasa.gov), developed by the NASA Goddard Earth Sciences Data and Information Services Center (GES DISC), allows access over 1900 satellite and model variables in 82 measurement groups of 8 disciplines without downloading data and software. Main features include basic functions for data analysis and visualization, data provenance, output data in different formats (ASCII, NetCDF, GeoTIFF), and more. Over the years, ~1700 peer-reviewed publications in different disciplines have been benefited from Giovanni in research activities (e.g. initial investigation, what-if questions, product evaluation). Despite the success of online visualization and analysis tools, challenges and new opportunities still exist and more can be done with new requirements and technology. Examples are: a) how to increase the efficiency of dataset search by enhancing intuitive aspects; b) how to facilitate interdisciplinary research; c) how to provide data quality information; d) how to engage users to participate in data quality assessment; and more. NASA Earth Observing System Data and Information System (EOSDIS) satellite-based data products are processed at various levels ranging from Level 0 to Level 4. While most users use data products at higher levels (Level-3 and 4), products at lower levels are still important for case studies, algorithm development, ground validation, etc. In this presentation, we will use Giovanni as an example to present and discuss challenges and near-future opportunities for satellite data online visualization and analysis tools.

Liu, Zhong↗
NASA NTRS2014

Experimental and Computational Sonic Boom Assessment of Boeing N+2 Low Boom Models

Near-field pressure signatures were measured and computational predictions made for several sonic boom models representing Boeing’s Quiet Experimental Validation Concept (QEVC) supersonic transport, as well as for three axisymmetric calibration models. The concept was designed under a NASA Research Announcement (NRA) contract to address environmental and performance goals, specifically for low sonic boom loudness levels and high cruise efficiency, for an aircraft anticipated to enter service in the 2020-timeframe. Wind tunnel tests were conducted on the aircraft and calibration models during Phases I and II of the NRA contract from 2011 to 2013 in the NASA Ames 9- by 7-Foot and NASA Glenn 8- by 6-Foot Supersonic Wind Tunnels. Sonic boom pressure signatures were acquired primarily at Mach 1.6 and 1.8, and force and moment data were acquired from Mach 0.8 to 1.8. The sonic boom test data were obtained using a 2-in. flat-top pressure rail and a 14-in. tapered “reflection factor 1” (RF1) pressure rail. Both rails capture an entire pressure signature in one data point, and successive signatures at varying positions along or above the rail were used to improve data quality through spatial averaging. The sonic boom data obtained by the rails were validated with high-fidelity numerical simulations of offbody pressures. The test results showed good agreement between the computational and experimental data when a variety of testing techniques including spatial averaging of a series of pressure signatures were employed. The two wind tunnels generally produced comparable data.

Durston, Donald A.↗