Engineering Papers⌕ Search

SEARCH · Engineering Papers

Results for “Systems 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 1,567 records · Page 87

User Instructions for the Policy Analysis Modeling System (PAMS)

PAMS uses country-specific and product-specific data to calculate estimates of impacts of a Minimum Efficiency Performance Standard (MEPS) program. The analysis tool is self-contained in a Microsoft Excel spreadsheet, and requires no links to external data, or special code additions to run. The analysis can be customized to a particular program without additional user input, through the use of the pull-down menus located on the Summary page. In addition, the spreadsheet contains many areas into which user-generated input data can be entered for increased accuracy of projection. The following is a step-by-step guide for using and customizing the tool.

97 MATHEMATICS AND COMPUTING↗

DOD/NASA system impact analysis (study 2.1). Volume 1: Executive summary

Results are reported from a study made to determine engineering and cost analyses regarding the elements of space transportation systems. Specifically, a tug turnaround cost and abort modes and effects analyses were made. Study approach and objectives for both elements are given.

Source record↗

Systems cost/performance analysis (study 2.3). Volume 2, appendix A: Data base

Data are presented on selected payload equipments (components) which were collected for the purpose of exercising the systems cost/performance model. Although most of the data is accurate, approximations based on engineering judgment and experience are used wherever actual data was unavailable. The equipments are organized according to the following subsystems which use the specific components: stabilization and control, auxiliary propulsion, data processing, communication, and electrical power. The data sheet for each component states which subsystem utilizes the component, which configurations require the component, which equipment type the component is categorized as, and the data base identifier or code number assigned to the component. The data describing the component consist of the following four types: performance, safety, cost, and schedule.

Campbell, B. H.↗

System for analysis of LANDSAT agricultural data: Automatic computer-assisted proportion estimation of local areas

The author has identified the following significant results. A conceptual man machine system framework was created for a large scale agricultural remote sensing system. The system is based on and can grow out of the local recognition mode of LACIE, through a gradual transition wherein computer support functions supplement and replace AI functions. Local proportion estimation functions are broken into two broad classes: (1) organization of the data within the sample segment; and (2) identification of the fields or groups of fields in the sample segment.

Nalepka, R. F.↗

Full-Envelope Launch Abort System Performance Analysis Methodology

The implementation of a new dispersion methodology is described, which dis-perses abort initiation altitude or time along with all other Launch Abort System (LAS) parameters during Monte Carlo simulations. In contrast, the standard methodology assumes that an abort initiation condition is held constant (e.g., aborts initiated at altitude for Mach 1, altitude for maximum dynamic pressure, etc.) while dispersing other LAS parameters. The standard method results in large gaps in performance information due to the discrete nature of initiation conditions, while the full-envelope dispersion method provides a significantly more comprehensive assessment of LAS abort performance for the full launch vehicle ascent flight envelope and identifies performance "pinch-points" that may occur at flight conditions outside of those contained in the discrete set. The new method has significantly increased the fidelity of LAS abort simulations and confidence in the results.

Aubuchon, Vanessa V.↗

PLANET-PLANET ECLIPSE AND THE ROSSITER-McLAUGHLIN EFFECT OF A MULTIPLE TRANSITING SYSTEM: JOINT ANALYSIS OF THE SUBARU SPECTROSCOPY AND THE KEPLER PHOTOMETRY

We report a joint analysis of the Rossiter-McLaughlin (RM) effect with Subaru and the Kepler photometry for the Kepler Object of Interest (KOI) 94 system. The system is comprised of four transiting planet candidates with orbital periods of 22.3 (KOI-94.01), 10.4 (KOI-94.02), 54.3 (KOI-94.03), and 3.7 (KOI-94.04) days from the Kepler photometry. We performed the radial velocity (RV) measurement of the system with the Subaru 8.2 m telescope on UT 2012 August 10, covering a complete transit of KOI-94.01 for {approx}6.7 hr. The resulting RV variation due to the RM effect spectroscopically confirms that KOI-94.01 is indeed the transiting planet and implies that its orbital axis is well aligned with the stellar spin axis; the projected spin-orbit angle {lambda} is estimated as -6{sup +13}{sub -11} deg. This is the first measurement of the RM effect for a multiple transiting system. Remarkably, the archived Kepler light curve around BJD = 2455211.5 (date in UT 2010 January 14/15) indicates a 'double-transit' event of KOI-94.01 and KOI-94.03, in which the two planets transit the stellar disk simultaneously. Moreover, the two planets partially overlap with each other, and exhibit a 'planet-planet eclipse' around the transit center. This provides a rare opportunity to put tight constraints on the configuration of the two transiting planets by joint analysis with our Subaru RM measurement. Indeed, we find that the projected mutual inclination of KOI-94.01 and KOI-94.03 is estimated to be {delta} = -1.{sup 0}15 {+-} 0.{sup 0}55. Implications for the migration model of multiple planet systems are also discussed.

79 ASTRONOMY AND ASTROPHYSICS↗

Rocketdyne automated dynamics data analysis and management system

An automated dynamics data analysis and management systems implemented on a DEC VAX minicomputer cluster is described. Multichannel acquisition, Fast Fourier Transformation analysis, and an online database have significantly improved the analysis of wideband transducer responses from Space Shuttle Main Engine testing. Leakage error correction to recover sinusoid amplitudes and correct for frequency slewing is described. The phase errors caused by FM recorder/playback head misalignment are automatically measured and used to correct the data. Data compression methods are described and compared. The system hardware is described. Applications using the data base are introduced, including software for power spectral density, instantaneous time history, amplitude histogram, fatigue analysis, and rotordynamics expert system analysis.

Tarn, Robert B.↗

Robust Distributed State Estimator for Interconnected Transmission and Distribution Networks (Final Report RPPR-1)

This project’s objective is to develop a combined transmission and distribution state estimator which accounts for very large system size and model complexity (by way of distributing the computations) and large number of solar PV units connected to the distribution system on multiple feeders. The project not only provides a robust formulation and solution to this problem but also tests the solution by implementing it on a well-established large utility system. It introduces several improvements with respect to the state of the art in existing state estimation software: (a) The developed state estimator (SE) allows robust and accurate monitoring of bidirectional flows in distribution systems which result due to the distributed energy sources which are not observable and thus not incorporated in generation dispatch; (b) Large utility systems with tens of thousands of transmission buses and hundreds of thousands of distribution nodes are difficult to model as a single integrated system. This shortcoming is addressed by developing a “scalable distributed computational framework” which allows splitting the ultra large system models into several small subsystems and coordinating their solution by a robust and practical state estimation formulation; (c) Measurement errors irrespective of their locations are detected and removed by the developed state estimator. Historically, transmission and distribution systems were analyzed and operated as two independent systems. Given the non-transposed short feeder sections, unevenly loaded phases, strictly radial configuration and unidirectional power flows in the absence of remote generation, distribution system analysis was customized to account for these characteristics. However, some of these assumptions are no longer valid (non-radial configuration, bidirectional power flows) and thus distribution system analysis should be revisited. Furthermore, in the past, the interaction between the transmission and distribution systems was quite passive, where distribution substations were modeled as lumped loads in the transmission system model. With substantial generation injected by renewable generation located in the distribution systems, such modeling will no longer be accurate. The developed state estimator facilitates proper monitoring of the interactions between the transmission and distribution systems and enables smart dispatch of these units which are made observable by the state estimator.

24 POWER TRANSMISSION AND DISTRIBUTION↗

Overhead and forward reach capability during exposure to +1 to +6 Gx loads

The lack of reach performance data obtained under space-flight conditions has led to questions regarding the operational impact of higher G loads on crew performance. This investigation studied the effect of increasing G loads on reach capability. Ten subjects were exposed in a stepwise fashion to increasing accelerations resulting in G loads of from +1 to +6 Gx in the Brooks AFB centrifuge. Four subjects wore the pre-Challenger Launch Entry Helmet (LEH) ensemble and six the current Launch Entry Suit (LES). The subjects performed standardized reach sweeps at each G level. These sweeps were recorded on videotape and subsequently analyzed using a 3-dimensional motion analysis system. Significant differences in forward and overhead reach were determined using the General Linear Models (GLM) procedure of the Statistical Analysis System (SAS) program. The results from this study suggest that purposeful movement can be realistically performed in the LEH at the 5 G level and in the LES up to the 4 G level.

G Suits/standards↗

Communications satellite systems capacity analysis

Analog and digital modulation techniques are compared with regard to efficient use of the geostationary orbit by communications satellites. Included is the definition of the baseline systems (both space and ground segments), determination of interference susceptibility, calculation of orbit spacing, and evaluation of relative costs. It is assumed that voice or TV is communicated at 14/11 GHz using either FM or QPSK modulation. Both the Fixed-Satellite Service and the Broadcasting-Satellite Service are considered. For most of the cases examined the digital approach requires a satellite spacing less than or equal to that required by the analog approach.

Browne, L.↗

Code validation of SAM using natural-circulation experimental data from the compact integral effects test (CIET) facility

The primary objective of this study is to validate the system analysis code, SAM, using experimental data from the Compact Integral Effects Test (CIET) experimental loop. SAM is a modern system analysis code being developed at Argonne National Laboratory for safety analysis of designs for advanced non-light water reactors (non-LWRs), such as sodium-cooled fast reactors, high-temperature gas-cooled reactors, and fluoride salt-cooled high-temperature reactors (FHRs). To support SAM code development for the wide range of non-LWR applications, it is of paramount importance to validate the code against experiments highly relevant to these reactor concepts. Additionally, the CIET facility, which was designed to reproduce the thermal-hydraulics response of FHRs under both forced- and natural-circulation conditions, has been identified and selected as one of the benchmark test facilities for SAM code validation. In this study, two sets of available CIET tests were selected for SAM code validation purposes, namely, power step change transient tests and steady-state natural-circulation tests. For all selected tests, SAM-predicted results show very good agreement with experimental data. The successful validation of SAM against these selected CIET experiments demonstrates that the computer code is well suited for thermal-hydraulics analysis of FHR designs.

42 ENGINEERING↗

Partial Support for the Federal Committee for Meteorological Services and Supporting Research

An interagency collaboration initiated between Navy, Air Force and NOAA and expanded to DOE, NASA, and NSF in 2012, for coordination of research to operations of a National earth system analysis and prediction capability. The goal of ESPC is to meet broad but specific agency requirements for an earth system analysis and prediction framework to support one-day to decadal global prediction at appropriate horizontal and vertical resolution; including the atmosphere, ocean, land, cryosphere, and space.

54 ENVIRONMENTAL SCIENCES↗

System reliability analysis through corona testing

In the Reliability and Quality Engineering Test Laboratory at the NASA Lewis Research Center a nondestructive, corona-vacuum test facility for testing power system components was developed using commercially available hardware. The test facility was developed to simulate operating temperature and vacuum while monitoring corona discharges with residual gases. This facility is being used to test various high voltage power system components.

Lalli, V. R.↗

Development of the Oleaginous Yeast Rhodosporidium Toruloides as a New Model Organism for a Systems-Level Analysis of Lipid Productivity

The goal of our project has been to develop one of the most productive oleaginous yeasts, Rhodosporidium toruloides, into a powerful model for systems-level research leading to the production of advanced biofuels. Under carbon-replete growth conditions in which nitrogen, sulfur or phosphorus are limiting, R. toruloides accumulates up to 70% of its dry weight in neutral lipids. We set out to find the genes that underlie this remarkable characteristic. To accomplish this, during the award period our team developed a functional-genomic toolkit for R. toruloides based on barcoded mutagenesis.

09 BIOMASS FUELS↗

The Status of Spacecraft Bus and Platform Technology Development under the NASA In-Space Propulsion Technology Program

NASA's In-Space Propulsion Technology (ISPT) program has been developing technologies for lowering the cost of planetary science missions. The technology areas include electric propulsion technologies, spacecraft bus technologies, entry vehicle technologies, and design tools for systems analysis and mission trajectories. The electric propulsion technologies include critical components of both gridded and non-gridded ion propulsion systems. The spacecraft bus technologies under development include an ultra-lightweight tank (ULTT) and advanced xenon feed system (AXFS). The entry vehicle technologies include the development of a multi-mission entry vehicle, mission design tools and aerocapture. The design tools under development include system analysis tools and mission trajectory design tools.

Anderson, David↗

Products from NASA's In-Space Propulsion Program Applicable to Low-Cost Planetary Missions

NASAs In-Space Propulsion Technology (ISPT) program has been developing technologies for lowering the cost of planetary science missions. The technology areas include electric propulsion technologies, spacecraft bus technologies, entry vehicle technologies, and design tools for systems analysis and mission trajectories. The electric propulsion technologies include critical components of both gridded and non-gridded ion propulsion systems. The spacecraft bus technologies under development include an ultra-lightweight tank (ULTT) and advanced xenon feed system (AXFS). The entry vehicle technologies include the development of a multi-mission entry vehicle, mission design tools and aerocapture. The design tools under development include system analysis tools and mission trajectory design tools.

Anderson, David↗

Parametric Cost Modeling of a Mid-Lift-to-Drag Ratio Vehicle for Human Mars Entry, Descent, and Landing

Cost is one of the biggest obstacles to sending humans to Mars. However, spacecraft costs are typically estimated after the preliminary vehicle and mission concepts have been designed. By automating the cost estimation process, the effect of any change in vehicle or mission design on the mission cost can be determined more rapidly. This paper uses the tool SAPE-C (Systems Analysis for Planetary Entry, Descent, and Landing-Cost). SAPE-C integrates the cost modeling software SEER-H (System Estimation and Evaluation of Resources-Hardware) with a number of systems analysis tools and enables large design tradespace exploration early in the design process. SAPE-C is used to analyze several tradespaces of the Mid-Lift-to-Drag ratio rigid entry vehicle for human Mars missions. Key findings include quantifying the impacts of payload, vehicle length, and main engine specific impulse on the overall cost of the vehicle, and how the payload per lander and number of landers affects the cost of a campaign to Mars.

Mid L/D↗

Parametric Cost Modeling of a Mid-Lift-to-Drag Ratio Vehicle for Human Mars Entry, Descent, and Landing

Cost is one of the biggest obstacles to sending humans to Mars. However, spacecraft costs are typically estimated after the preliminary vehicle and mission concepts have been designed. By automating the cost estimation process, the effect of any change in vehicle or mission design on the mission cost can be determined more rapidly. This paper uses the tool SAPE-C (Systems Analysis for Planetary Entry, Descent, and Landing-Cost). SAPE-C integrates the cost modeling software SEER-H (System Estimation and Evaluation of Resources-Hardware) with a number of systems analysis tools and enables large design tradespace exploration early in the design process. SAPE-C is used to analyze several tradespaces of the Mid-Lift-to-Drag ratio rigid entry vehicle for human Mars missions. Key findings include quantifying the impacts of payload, vehicle length, and main engine specific impulse on the overall cost of the vehicle, and how the payload per lander and number of landers affects the cost of a campaign to Mars.

Paul D Friz↗