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Results for “Sensitivity 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.
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Sensitivity Analysis of Air/Carbon Finite-Rate Surface Ablation Models.
Abstract not provided.
Defining and Measuring Forest Dependence in the United States: Operationalization and Sensitivity Analysis
This manuscript helps bridge a gap between theoretical work that advocates for a broad view of forest dependence, and empirical work that has focused narrowly on economic measures. Background: Forest dependence has been widely recognized as a valuable concept for understanding human communities’ well-being and vulnerability to shocks and changes. Past theoretical literature has highlighted the importance of recognizing various types of dependence—environmental, economic, and social—yet past empirical literature on the topic in the United States has almost exclusively relied on measures of economic dependence such as employment and earnings from the traditional forest products sector. Objective and Methods: As a first step to bridge the gap between the theoretical and empirical, we reviewed the existing, publicly available, reliable, wall-to-wall data sources to identify alternate proxy measures for forest dependence. Data availability made the analysis feasible only at the county level—the administrative subdivisions of the state—or higher. Results and Conclusions: We created environmental, economic, and social criteria based on threshold levels of the following proxy variables: forest area, earnings, employment, and indigenous population. Using these criteria, we identified 524 counties to be potentially forest-dependent of 3140 total counties in the United States. The largest concentration was in the Pacific Northwest and Southeast regions, and a higher proportion were non-metro counties than metro. Varying the threshold levels significantly changes the number of counties identified but does not alter the overall geographic trends.
Graphical methods for the sensitivity analysis in discriminant analysis
Similar to regression, many measures to detect influential data points in discriminant analysis have been developed. Many follow similar principles as the diagnostic measures used in linear regression in the context of discriminant analysis. Here we focus on the impact on the predicted classification posterior probability when a data point is omitted. The new method is intuitive and easily interpretative compared to existing methods. We also propose a graphical display to show the individual movement of the posterior probability of other data points when a specific data point is omitted. This enables the summaries to capture the overall pattern of the change.
Evaluating Soil Moisture–Precipitation Interactions Using Remote Sensing: A Sensitivity Analysis
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Temperature sensitivity analysis on mass-spring potential with electrostatic frequency reduction for lunar seismometers
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Mangrove carbon assessment tool: Model development and sensitivity analysis
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Parametric sensitivity analysis for staged propulsive vehicles
Random variable method of analyzing propulsion system performance and stage inert weight of two stage rocket vehicles
Network support simulation and sensitivities analysis for the Saturn-Apollo missions
Real time network support simulation allowing network configuration for nominal or perturbed trajectory for Saturn vehicles, applicable to any flight azimuth
Topological formulation of symbolic network functions and sensitivity analysis of active networks
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A computer program for the use of sensitivity analysis in display evaluation
A description is provided of the Display Evaluation computer program, some results of this program and comparison of these results with a simple experiment. A detailed description of the experiment and data analysis are also included.
Economic and engineering implications of the Project Independence 1985 geothermal energy output goal and the associated sensitivity analysis
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Sensitivity analysis and comparison of salt deposition models for cooling towers
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Design tradeoff studies and sensitivity analysis, appendices B1 - B4
Documentation is presented for a program which separately computes fuel and energy consumption for the two modes of operation of a hybrid electric vehicle. The distribution of daily travel is specified as input data as well as the weights which the component driving cycles are given in each of the composite cycles. The possibility of weight reduction through the substitution of various materials is considered as well as the market potential for hybrid vehicles. Data relating to battery compartment weight distribution and vehicle handling analysis is tabulated.
Sensitivity analysis of upwelling thermal radiance in presence of clouds
Total upwelling radiance at the top of the atmosphere is evaluated theoretically in the presence of clouds. The influence of cloud heights, thicknesses and different cloud covers on the upwelling radiance is also investigated. The characteristics of the two cloud types considered in this study closely correspond to altocumulus and cirrus with the cloud emissivity as a function of its liquid water (or ice) content. For calculation of the integrated transmittance of atmospheric gases such as, H2O, CO2, O3, and N2O, the Quasi Random Band (QRB) model approach is adopted. Results are obtained in three different spectral ranges and are compared with the clearsky radiance results. It is found that the difference between the clearsky and cloudy radiance increases with increasing cloud height and liquid water content. This difference also decreases as the surface temperature approaches the value of the cloud top temperature.
Sensitivity analysis of physiological factors in space habitat design
The costs incurred by design conservatism in space habitat design are discussed from a structural standpoint, and areas of physiological research into less than earth-normal conditions that offer the greatest potential decrease in habitat construction and operating costs are studied. The established range of human tolerance limits is defined for those physiological conditions which directly affect habitat structural design. These entire ranges or portions thereof are set as habitat design constraints as a function of habitat population and degree of ecological closure. Calculations are performed to determine the structural weight and cost associated with each discrete population size and its selected environmental conditions, on the basis of habitable volume equivalence for four basic habitat configurations: sphere, cylinder with hemispherical ends, torus, and crystal palace.
Sensitivity analysis of cool-down strategies for a transonic cryogenic tunnel
Guidelines and suggestions substantiated by real-time simulation data to ensure optimum time and energy use of injected liquid nitrogen for cooling the Langley 0.3-Meter Transonic Cryogenic Tunnel (TCT) are presented. It is directed toward enabling operators and researchers to become cognizant of criteria for using the 0.3-m TCT in an energy- or time-efficient manner. Operational recommendations were developed based on information collected from a validated simulator of the 0.3-m TCT and experimental data from the tunnel. Results and trends, however, can be extrapolated to other similarly constructed cryogenic wind tunnels.
Textural edge detection and sensitivity analysis
An optimum (global) textural edge detection operator based on statistical models for texture was developed. Also the effects of the imaging process on the textural patterns of a scene as it appears in the image were analyzed.