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NASA NTRS2013

Evaluation of the Impact of AlRS Radiance and Profile Data Assimilation in Partly Cloudy Regions

Parallel experiments using AIRS L1B and L2 retrieved profiles were run for 29 case study days for early Winter 2011. Forecasts over and downstream regions of low, opaque cloudy regions yield improved T and Z anomaly correlations when non-thinned set of profiles is assimilated instead of radiances. Initial results indicate that GSI does a good job on the whole of determining cloud-free radiances there are some areas coincident with areas of larger profile impact that are misrepresented (compared to MODIS) that may result in reduced analysis impact.

Zavodsky, Bradely↗

NASA NTRSDate not supplied

A Systematic Framework for Investigating Climate Impact-Drivers in NASA GISS ModelE Configurations: Towards Improving ESM Development for Impact Applications

Earth System Model (ESM) development benefits from attention to the downstream applications for nature and society. The evaluation of ESMs often focuses on a limited set of climatic impact-drivers (CIDs)1 and numerous large-scale parameters that are not directly relevant for impact analysis. To address this limitation, we propose a comprehensive framework for impact-relevant model version comparison. This framework explores both the intended and unintended consequences of shifts in model components, parameters, and resolutions, emphasizing the perspectives of the climate impacts community. We have selected a core set of CIDs as a basis for comparing model versions.

earth system models↗

NASA NTRS1991

Hypervelocity Impact Physics

All large spacecraft are susceptible to impacts by meteoroids and orbiting space debris. These impacts occur at extremely high speed and can damage flight-critical systems, which can in turn lead to a catastrophic failure of the spacecraft. Therefore, the design of a spacecraft for a long-duration mission must take into account the possibility of such impacts and their effects on the spacecraft structure and on all of its exposed subsystems components. The work performed under the contract consisted of applied research on the effects of meteoroid/space debris impacts on candidate materials, design configurations, and support mechanisms of long term space vehicles. Hypervelocity impact mechanics was used to analyze the damage that occurs when a space vehicle is impacted by a micrometeoroid or a space debris particle. An impact analysis of over 500 test specimens was performed to generate by a hypervelocity impact damage database.

William P Schonberg↗

NASA NTRS2013

Maintaining the Health of Software Monitors

Software health management (SWHM) techniques complement the rigorous verification and validation processes that are applied to safety-critical systems prior to their deployment. These techniques are used to monitor deployed software in its execution environment, serving as the last line of defense against the effects of a critical fault. SWHM monitors use information from the specification and implementation of the monitored software to detect violations, predict possible failures, and help the system recover from faults. Changes to the monitored software, such as adding new functionality or fixing defects, therefore, have the potential to impact the correctness of both the monitored software and the SWHM monitor. In this work, we describe how the results of a software change impact analysis technique, Directed Incremental Symbolic Execution (DiSE), can be applied to monitored software to identify the potential impact of the changes on the SWHM monitor software. The results of DiSE can then be used by other analysis techniques, e.g., testing, debugging, to help preserve and improve the integrity of the SWHM monitor as the monitored software evolves.

Runtime Monitor↗

NASA NTRS2001

Auburn Micrometeoroid Impact Test Data Analysis

This presentation provides an overview and summary of micrometeoroid impact testing performed by Auburn University and an analysis of the test results. The testing at Auburn utilized existing facilities at Auburn to generate hypervelocity impacts into multiple layers of thin Kapton films representative of the NASA concept for the NGST sunshield. The test data consists of impactor particle mass and velocity, and for each film layer, the number and size of holes generated by the initial impact and resulting impact debris. The analysis consists of combining the test data with existing impact effects models and the micrometeoroid environment at the L2 operating location of NGST to predict sunshield degradation.

Perrygo, Charles↗

NASA NTRS2014

Carbon-Temperature-Water Change Analysis for Peanut Production Under Climate Change: A Prototype for the AgMIP Coordinated Climate-Crop Modeling Project (C3MP)

Climate change is projected to push the limits of cropping systems and has the potential to disrupt the agricultural sector from local to global scales. This article introduces the Coordinated Climate-Crop Modeling Project (C3MP), an initiative of the Agricultural Model Intercomparison and Improvement Project (AgMIP) to engage a global network of crop modelers to explore the impacts of climate change via an investigation of crop responses to changes in carbon dioxide concentration ([CO2]), temperature, and water. As a demonstration of the C3MP protocols and enabled analyses, we apply the Decision Support System for Agrotechnology Transfer (DSSAT) CROPGRO-Peanut crop model for Henry County, Alabama, to evaluate responses to the range of plausible [CO2], temperature changes, and precipitation changes projected by climate models out to the end of the 21st century. These sensitivity tests are used to derive crop model emulators that estimate changes in mean yield and the coefficient of variation for seasonal yields across a broad range of climate conditions, reproducing mean yields from sensitivity test simulations with deviations of ca. 2% for rain-fed conditions. We apply these statistical emulators to investigate how peanuts respond to projections from various global climate models, time periods, and emissions scenarios, finding a robust projection of modest (<10%) median yield losses in the middle of the 21st century accelerating to more severe (>20%) losses and larger uncertainty at the end of the century under the more severe representative concentration pathway (RCP8.5). This projection is not substantially altered by the selection of the AgMERRA global gridded climate dataset rather than the local historical observations, differences between the Third and Fifth Coupled Model Intercomparison Project (CMIP3 and CMIP5), or the use of the delta method of climate impacts analysis rather than the C3MP impacts response surface and emulator approach.

climate change↗

NASA NTRS1976

Microeconomic analysis of military aircraft bearing restoration

Hein, G. F.↗

NASA NTRS1976

Microeconomic analysis of military aircraft bearing restoration

The risk and cost of a bearing restoration by grinding program was analyzed. A microeconomic impact analysis was performed. The annual cost savings to U.S. Army aviation is approximately $950,000.00 for three engines and three transmissions. The capital value over an indefinite life is approximately ten million dollars. The annual cost savings for U.S. Air Force engines is approximately $313,000.00 with a capital value of approximately 3.1 million dollars. The program will result in the government obtaining bearings at lower costs at equivalent reliability. The bearing industry can recover lost profits during a period of reduced demand and higher costs.

Hein, G. F.↗

NASA NTRS2009

Recent Shuttle Post Flight MMOD Inspection Highlights

Post flight inspections on the Space Shuttle Atlantis conducted after the STS-11.5 mission revealed a 0.11 inch (2.8 mm) hole in the outer face sheet of the starboard payload bay door radiator panel #4. The payload bay door radiators in this region are 0.5 inch (12.7 mm) thick aluminum honeycomb with 0.011 in (0.279 mm) thick aluminum face sheets topped with 0.005 in (0.127 mm) silver-Teflon tape. Inner face sheet damage included a 0.267 in (6.78 mm) long through crack with measureable deformation in the area of 0.2 in (5.1 mm). There was also a 0.031 in (0.787 nun) diameter hole in the rear face sheet. A large approximately l in (25 mm) diameter region of honeycomb was also destroyed. Since the radiators are located on the inside of the shuttle payload bay doors which are closed during ascent and reentry, the damage could only have occurred during the on-orbit portion of the mission. During the August 2007 STS-118 mission to the International Space Station, a micro-meteoroid or orbital debris (MMOD) particle impacted and completely penetrated one of shuttle Endeavour's radiator panels and the underlying thermal control system (TCS) blanket, leaving deposits on (but no damage to) the payload bay door. While it is not unusual for shuttle orbiters to be impacted by small MMOD particles, the damage from this impact is larger than any previously seen on the shuttle radiator panels. One of the largest impacts ever observed on a crew module window occurred during the November 2008 STS-126 mission to the International Space Station. Damage to the window was documented by the crew on orbit. Post flight inspection revealed a 0.4 in (10.8 mm) crater in the window pane, with a depth of 0.03 in (0.76 mm). The window pane was replaced due to the damage caused by this impact. Analysis performed on residue contained in dental mold impressions taken of the site indicated that a meteoroid particle produced this large damage site. The post flight inspection after the subsequent mission, STS-119 in March of 2009, produced a large MMOD impact feature in a wing leading edge reinforced carbon-carbon panel. The crater measured 0.18 in (4.5 nun) in diameter and was nearly 0.037 in (0.93 nun) deep. The thickness of the silicon carbide coating that protects the carbon substrate is nominally 0.02 in (0.5 nun) to 0.04 in (1 mm), making this a significant impact into the RCC. The damage occurred on the upper surface of the panel, which experiences lower heat loads on re-entry. This poster will document the data collected from the impact sites and will include results of the Scanning Electron Microscope/Energy Dispersive X-ray (SEM/EDX) analysis. Evidence will be presented that suggests a source of the impacts.

Hyed, James L.↗

NASA NTRS2010

Hypervelocity Impact Testing of IM7/977-3 with Micro-Sized Particles

Ground-based hypervelocity imapct testing was conducted on IM7/977-3 quasi-isotropic flat panels at normal incidence using micron-sized particles (i.e. less than or equal to 100 microns) of soda lime glass and olivine. Testing was performed at room temperature (RT) and 175 C with results from the 175 C test compared to those obtained at RT. Between 10 and 30 particles with velocities ranging from 5 to 13 km/s impacted each panel surface for each test temperature. Panels were ultrasonically scanned prior to and after impact testing to assess internal damage. Post-impact analysis included microscopic examination of the surface, determination of particle speed and location, and photomicroscopy for microcrack assessment. Internal damage was observed by ultrasonic inspection on panels impacted at 175 C, whereas damage for the RT impacted panels was confined to surface divets/craters as determined by microscopic analysis.

Smith, J. G.↗

NASA NTRS1974

The NASA Ames integral aircraft passenger seat concept - A human engineering approach

A new NASA Ames concept for an aircraft passenger seat has been under research and development since 1968. It includes many human-factor features that will provide protection to the passenger from vibration, jostle, and high impact. It is comfortable and safer than any of the seats presently in use. An in-depth design, fabrication, and impact analysis was conducted in order to design a seat that will maximize passenger protection in high g impacts (20 g horizontal -Gx, 36 g vertical +Gz, 16 g lateral Gy). The method for absorbing impact energy was accomplished with a combination of stretching stainless steel cables, thread breaking of stitches, hydraulic mechanism and the special Temper Form cushions. The restraint system for the seat consisted of a lap belt and shoulder harness inertia reel combination.

Kubokawa, C. C.↗

NASA NTRS1975

Generating social impact scenarios: A key step in making technology assessment studies

The MITRE methodological studies were conducted to define relevant questions in relation to the concept of total impact analysis and to provide a procedure for integrating diverse checklists of questions which trace the initial and secondary impacts of any major technological application or of society's attempts to respond to or redirect that application. Some of the results of that study are presented in tabular form.

Jones, M. V.↗

NASA NTRS2014

Multi-Mission System Analysis for Planetary Entry (M-SAPE) Version 1

This report describes an integrated system for Multi-mission System Analysis for Planetary Entry (M-SAPE). The system in its current form is capable of performing system analysis and design for an Earth entry vehicle suitable for sample return missions. The system includes geometry, mass sizing, impact analysis, structural analysis, flight mechanics, TPS, and a web portal for user access. The report includes details of M-SAPE modules and provides sample results. Current M-SAPE vehicle design concept is based on Mars sample return (MSR) Earth entry vehicle design, which is driven by minimizing risk associated with sample containment (no parachute and passive aerodynamic stability). By M-SAPE exploiting a common design concept, any sample return mission, particularly MSR, will benefit from significant risk and development cost reductions. The design provides a platform by which technologies and design elements can be evaluated rapidly prior to any costly investment commitment.

Samareh, Jamshid↗

NASA NTRS1979

Development of crashworthy passenger seats for general-aviation aircraft

Two types of energy absorbing passenger seat concepts suitable for installation in light twin-engine fixed wing aircraft were developed. An existing passenger seat for such an aircraft was used to obtain the envelope constraints. Ceiling suspended and floor supported seat concept designs were developed. A restraint system suitable for both concepts was designed. Energy absorbing hardware for both concepts was fabricated and tension and compression tests were conducted to demonstrate the stroking capability and the force deflection characteristics. Crash impact analysis was made and seat loads developed. The basic seat structures were analyzed to determine the adequacy of their strength under impact loading.

Reilly, M. J.↗

NASA NTRS1989

New computing systems and their impact on structural analysis and design

A review is given of the recent advances in computer technology that are likely to impact structural analysis and design. The computational needs for future structures technology are described. The characteristics of new and projected computing systems are summarized. Advances in programming environments, numerical algorithms, and computational strategies for new computing systems are reviewed, and a novel partitioning strategy is outlined for maximizing the degree of parallelism. The strategy is designed for computers with a shared memory and a small number of powerful processors (or a small number of clusters of medium-range processors). It is based on approximating the response of the structure by a combination of symmetric and antisymmetric response vectors, each obtained using a fraction of the degrees of freedom of the original finite element model. The strategy was implemented on the CRAY X-MP/4 and the Alliant FX/8 computers. For nonlinear dynamic problems on the CRAY X-MP with four CPUs, it resulted in an order of magnitude reduction in total analysis time, compared with the direct analysis on a single-CPU CRAY X-MP machine.

Noor, Ahmed K.↗

NASA NTRS2020

An Integrated Model of Models for Global Flood Alerting

A dramatic increase in frequency of minor to major flooding since 2000 has caused significant damage to infrastructure and economic losses across the world. To mitigate and recover from these losses, actions have been taken to build resilient communities and infrastructures. Situational awareness in near real-time is essential to ensure community resilience and enhance response and recovery efforts. Several hydrologic and hydraulic flood models are available at various spatial and temporal resolutions at regional to global scale. Given the global coverage of two operational flood models - GloFAS (Global Flood Awareness System) and GFMS (Global Flood Monitoring System), the first component of this project first focuses on integrating the outputs from these two models to classify flood severity and send alerts based on potential for impacts similar to the USGS PAGER (used for severity alerting and impact analysis for earthquakes). The second component of the project focuses on using flood outputs derived from earth observation data to validate, update and add additional exposure and impact products to flood alerts. The flood impacts and severity information will be disseminated as alerts and maps through the DisasterAWARE platform, operated by the Pacific Disaster Center (PDC), that provides global multi-hazard alerting and Situational Awareness information to the emergency management community and public. In this presentation, the following objectives will be covered: (i) the effective integration of the flood models, (ii) accuracy of the flood model outputs (flood extent and depth) for specific flood events both in the United States and globally in comparison with each other and earth observation data.

Glasscoe, Margaret↗

NASA NTRS1989

Space Station accommodation of life sciences in support of a manned Mars mission

Results of a life science impact analysis for accommodation to the Space Station of a manned Mars mission are discussed. In addition to addressing such issues as on-orbit vehicle assembly and checkout, the study also assessed the impact of a life science research program on the station. A better understanding of the effects on the crew of long duration exposure to the hostile space environment and to develop controls for adverse effects was the objective. Elements and products of the life science accommodation include: the identification of critical research areas; the outline of a research program consistent with the mission timeframe; the quantification of resource requirements; the allocation of functions to station facilities; and a determination of the impact on the Space Station program and of the baseline configuration. Results indicate the need at the Space Station for two dedicated life science lab modules; a pocket lab to support a 4-meter centrifuge; a quarantine module for the Mars Sample Return Mission; 3.9 man-years of average crew time; and 20 kilowatts of electrical power.

Meredith, Barry D.↗

NASA NTRS2010

Space Weather Models, Tools and Services at the Community Coordinated Modeling Center

The Community Coordinated Modeling center (CCMC) is a multi-agency partnership to support the research and developmental work necessary to substantially increase space weather modeling capabilities and to facilitate advanced models deployment in forecasting operations. The CCMC conducts unbiased model testing and validation and evaluates model readiness for operational environment. Space weather models and coupled model chains hosted at the CCMC range from the solar corona to the Earth's upper atmosphere. CCMC has developed a number of real-time modeling systems, as well as a large number of modeling and data products tailored to address the space weather needs of NASA's robotic missions. The presentation will demonstrate the rapid progress towards development the system allowing using products derived from space weather models in applications associated with National Space Weather needs. The adaptable Integrated Space Weather Analysis (ISWA) System developed at CCMC for NASA-relevant space weather information combines forecasts based on advanced space weather models hosted at CCMC with concurrent space environment information. The system is also enabling post-impact analysis and flexible dissemination of space weather information.

Kuznetsova, M. M.↗