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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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At least 1,009 records · Page 56

Success Path Method: Implementation Guidance

This document provides a guide regarding the application of the Argonne National Laboratory (Argonne) Success Path Method (SPM) for the management of risk(s) of processes associated with organizational objectives. The current work provides an approach to implement the set of standard (higher level) requirements for the SPM. A companion document for Process Specific Applications, which is current under development, provides additional guidance regarding how the general implementation description detailed here can be adapted to the evaluation of specific processes.

97 MATHEMATICS AND COMPUTING↗

The 100 cm solar telescope primary mirror study

The manufacturing impact of primary mirror configuration on the performance of a 100 cm aperture solar telescope was studied. Three primary mirror configurations were considered: solid, standard lightweight, and mushroom. All of these are of low expansion material. Specifically, the study consisted of evaluating the mirrors with regard to: manufacturing metrology, manufacturing risk factors and ultimate quality assessment. As a result of this evaluation, a performance comparison of the configurations was made, and a recommendation of mirror configuration is the final output. These evaluations, comparisons and recommendations are discussed in detail. Other investigations were completed and are documented in the appendices.

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Principles and methods for future low-cost planetary exploration

This paper describes the approach that NASA will use to obtain the mandatory science results with a minimum expenditure of resources for the new thrusts which will be initiated. The specific projects that will be described to illustrate the planned utilization of standardized hardware and software are the Outer Planet Orbiter/Probe (Jupiter) and the Terrestrial Bodies Orbiter (Lunar) missions. This paper describes the coupling between these missions and future missions to a variety of bodies in the solar system and the benefits to be derived by developing a design that will accommodate future missions as opposed to optimized designs for each individual mission.

Kraemer, R. S.↗

Solar-heating system design package

Report describes solar heating system composed of warm-air solar collector, logic control unit, and switching and transport unit, that meets government standards for installation in residential dwellings. Text describes system operation and performance specifications complemented by comprehensive set of subcomponent design drawings.

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Physics through the 1990s: Nuclear physics

The volume begins with a non-mathematical introduction to nuclear physics. A description of the major advances in the field follows, with chapters on nuclear structure and dynamics, fundamental forces in the nucleus, and nuclei under extreme conditions of temperature, density, and spin. Impacts of nuclear physics on astrophysics and the scientific and societal benefits of nuclear physics are then discussed. Another section deals with scientific frontiers, describing research into the realm of the quark-gluon plasma; the changing description of nuclear matter, specifically the use of the quark model; and the implications of the standard model and grand unified theories of elementary-particle physics; and finishes with recommendations and priorities for nuclear physics research facilities, instrumentation, accelerators, theory, education, and data bases. Appended are a list of national accelerator facilities, a list of reviewers, a bibliography, and a glossary.

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Research papers and publications (1981-1987): Workload research program

An annotated bibliography of the research reports written by participants in NASA's Workload Research Program since 1981 is presented, representing the results of theoretical and applied research conducted at Ames Research Center and at universities and industrial laboratories funded by the program. The major program elements included: 1) developing an understanding of the workload concept; 2) providing valid, reliable, and practical measures of workload; and 3) creating a computer model to predict workload. The goal is to provide workload-related design principles, measures, guidelines, and computational models. The research results are transferred to user groups by establishing close ties with manufacturers, civil and military operators of aerospace systems, and regulatory agencies; publishing scientific articles; participating in and sponsoring workshops and symposia; providing information, guidelines, and computer models; and contributing to the formulation of standards. In addition, the methods and theories developed have been applied to specific operational and design problems at the request of a number of industry and government agencies.

Hart, Sandra G.↗

Expert mission planning and replanning scheduling system for NASA KSC payload operations

EMPRESS (Expert Mission Planning and REplanning Scheduling System) is an expert system created to assist payload mission planners at Kennedy in the long range planning and scheduling of horizontal payloads for space shuttle flights. Using the current flight manifest, these planners develop mission and payload schedules detailing all processing to be performed in the Operations and Checkout building at Kennedy. With the EMPRESS system, schedules are generated quickly using standard flows that represent the tasks and resources required to process a specific horizontal carrier. Resources can be tracked and resource conflicts can be determined and resolved interactively. Constraint relationships between tasks are maintained and can be enforced when a task is moved or rescheduled. The domain, structure, and functionality of the EMPRESS system is briefly designed. The limitations of the EMPRESS system are described as well as improvements expected with the EMPRESS-2 development.

Pierce, Roger↗

USL/DBMS NASA/PC R and D project system design standards

A set of system design standards intended to assure the completeness and quality of designs developed for PC research and development projects is established. The standards presented address the areas of problem definition, initial design plan, design specification, and re-evaluation.

Dominick, Wayne D.↗

An SSE approach to reusability

The SSE project has engineering analysis and design efforts under way for the development of the SSE reusability library management system. An ad hoc committee on reuse has been meeting for several months identifying design considerations and learning about Ruben Prieto-Diaz faceted classification, CAMP domain analysis, SPC activities, SEI activities, and SPS activities. A standard format was developed for the Ada prologue for reusable components (both specification and body). The SSE reusability process can be viewed as a transformation process with minimized losses and difficulties.

Badal, David L.↗

NASA's strategic plan for education. A strategy for change, 1993-1998

NASA's education vision is to promote excellence in America's education system through enhancing and expanding scientific and technological competence. In doing so, NASA strives to be recognized by the education community as the premier mission agency in support of the National Education Goals and in the development and implementation of education standards. To realize this vision, NASA has clearly defined and developed three specific goals to promote excellence in education. Specific objectives and milestones are defined for each goal in the body of this strategic plan.

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NASA data exchange standards for computational fluid dynamics

This presentation covers the following topics in viewgraph format: purpose of data exchange standards; data exchange in engineering analysis/CFD; geometry data exchange through existing product data exchange standards, NASA Data Exchange Committee, and NASA-IGES (Initial Graphics Exchange Specification); CFD grid and solution data exchange; and data exchange for multi-disciplinary engineering.

Matthew Blake↗

Performance of an Electro-Hydrostatic Actuator on the F-18 Systems Research Aircraft

An electro-hydrostatic actuator was evaluated at NASA Dryden Flight Research Center, Edwards, California. The primary goal of testing this actuator system was the flight demonstration of power-by-wire technology on a primary flight control surface. The electro-hydrostatic actuator uses an electric motor to drive a hydraulic pump and relies on local hydraulics for force transmission. This actuator replaced the F-18 standard left aileron actuator on the F-18 Systems Research Aircraft and was evaluated throughout the Systems Research Aircraft flight envelope. As of July 24, 1997 the electro-hydrostatic actuator had accumulated 23.5 hours of flight time. This paper presents the electro-hydrostatic actuator system configuration and component description, ground and flight test plans, ground and flight test results, and lessons learned. This actuator performs as well as the standard actuator and has more load capability than required by aileron actuator specifications of McDonnell- Douglas Aircraft, St. Louis, Missouri. The electro-hydrostatic actuator system passed all of its ground tests with the exception of one power-off test during unloaded dynamic cycling.

Robert Navarro↗

Locating Stardust-like Particles in Aerogel Using X-Ray Techniques

Silica aerogel is the material that the spacecraft STARDUST is using to collect interstellar and cometary silicates. Anticipating the return of the samples to earth in January of 2006, MANY individual investigators and, especially, the investigators in NASA's SRLIDAP program are studying means of both in situ analysis of particles, as well as particle extraction. To help individual PI's with extraction of particles from aerogel in their own laboratories, we are exploring the use of standard laboratory x-ray equipment and commercial techniques for precisely locating specific particles in aerogel. We approached the evaluation of commercial x-ray techniques as follows. First, we determined the most appropriate detector for use with aerogel and particulates. Then, we compared and contrasted techniques useful for university laboratories.

Jurewicz, A. J. G.↗

A Modified LC/MS/MS Method with Enhanced Sensitivity for the Determination of Scopolamine in Human Plasma

Intranasal scopolamine is a choice drug for the treatment of motion sickness during space flight because of its quick onset of action, short half-life and favorable sideeffects profile. The dose administered usually ranges between 0.1 and 0.4 mg. Such small doses make it difficult to detect concentrations of scopolamine in biological fluids using existing sensitive LC/MS/MS method, especially when the biological sample volumes are limited. To measure scopolamine in human plasma to facilitate pharmacokinetic evaluation of the drug, we developed a sensitive LC/MS/MS method using 96 well micro elution plates for solid phase extraction (SPE) of scopolamine in human plasma. Human plasma (100-250 micro L) were loaded onto Waters Oasis HLB 96 well micro elution plate and eluted with 50 L of organic solvent without evaporation and reconstitution. HPLC separation of the eluted sample was performed using an Agilent Zorbax SB-CN column (50 x 2.1 mm) at a flow rate of 0.2 mL/min for 3 minutes. The mobile phase for separation was 80:20 (v/v) methanol: ammonium acetate (30 mM) in water. Concentrations of scopolamine were determined using a Micromass Quattro Micro(TM) mass spectrometer with electrospray ionization (ESI). ESI mass spectra were acquired in positive ion mode with multiple reaction monitoring for the determination of scopolamine m/z = 304.2 right arrow 138.1 and internal standard hyoscyamine m/z = 290.2 right arrow 124.1. The method is rapid, reproducible, specific and has the following parameters: scopolamine and the IS are eluted at about 1.1 and 1.7 min respectively. The linear range is 25-10000 pg/mL for scopolamine in human plasma with correlation coefficients greater than 0.99 and CV less than 0.5%. The intra-day and inter-day CVs are less than 15% for quality control samples with concentrations of 75,300, and 750 pg/mL of scopolamine in human plasma. SPE using 96 well micro elution plates allows rapid sample preparation and enhanced sensitivity for the LC/MS/MS determination of scopolamine in a small volume of biological samples. The new method is also cost effective since it uses a small volume of organic solvents compared to the methods using SPE cartridges or regular 96 well SPE plates. This method can be successfully used for bioavailability and pharmacokinetic evaluations of scopolamine, especially when volumes of biological samples are limited. Further investigation to use automated SPE system with 96 well micro elution plates is planned.

Wang, Zuwei↗

Dynamic Server-Based KML Code Generator Method for Level-of-Detail Traversal of Geospatial Data

Web-based geospatial client applications such as Google Earth and NASA World Wind must listen to data requests, access appropriate stored data, and compile a data response to the requesting client application. This process occurs repeatedly to support multiple client requests and application instances. Newer Web-based geospatial clients also provide user-interactive functionality that is dependent on fast and efficient server responses. With massively large datasets, server-client interaction can become severely impeded because the server must determine the best way to assemble data to meet the client applications request. In client applications such as Google Earth, the user interactively wanders through the data using visually guided panning and zooming actions. With these actions, the client application is continually issuing data requests to the server without knowledge of the server s data structure or extraction/assembly paradigm. A method for efficiently controlling the networked access of a Web-based geospatial browser to server-based datasets in particular, massively sized datasets has been developed. The method specifically uses the Keyhole Markup Language (KML), an Open Geospatial Consortium (OGS) standard used by Google Earth and other KML-compliant geospatial client applications. The innovation is based on establishing a dynamic cascading KML strategy that is initiated by a KML launch file provided by a data server host to a Google Earth or similar KMLcompliant geospatial client application user. Upon execution, the launch KML code issues a request for image data covering an initial geographic region. The server responds with the requested data along with subsequent dynamically generated KML code that directs the client application to make follow-on requests for higher level of detail (LOD) imagery to replace the initial imagery as the user navigates into the dataset. The approach provides an efficient data traversal path and mechanism that can be flexibly established for any dataset regardless of size or other characteristics. The method yields significant improvements in userinteractive geospatial client and data server interaction and associated network bandwidth requirements. The innovation uses a C- or PHP-code-like grammar that provides a high degree of processing flexibility. A set of language lexer and parser elements is provided that offers a complete language grammar for writing and executing language directives. A script is wrapped and passed to the geospatial data server by a client application as a component of a standard KML-compliant statement. The approach provides an efficient means for a geospatial client application to request server preprocessing of data prior to client delivery. Data is structured in a quadtree format. As the user zooms into the dataset, geographic regions are subdivided into four child regions. Conversely, as the user zooms out, four child regions collapse into a single, lower-LOD region. The approach provides an efficient data traversal path and mechanism that can be flexibly established for any dataset regardless of size or other characteristics.

Baxes, Gregory↗

Facility Systems, Ground Support Systems, and Ground Support Equipment General Design Requirements

KSC-DE-512-SM establishes overall requirements and best design practices to be used at the John F. Kennedy Space Center (KSC) for the development of ground systems (GS) in support of operations at launch, landing, and retrieval sites. These requirements apply to the design and development of hardware and software for ground support equipment (GSE), ground support systems (GSS), and facility ground support systems (F-GSS) used to support the KSC mission for transportation, receiving, handling, assembly, test, checkout, servicing, and launch of space vehicles and payloads and selected flight hardware items for retrieval. This standards manual supplements NASA-STD-5005 by including KSC-site-specific and local environment requirements. These requirements and practices are optional for equipment used at manufacturing, development, and test sites.

Ground Support Systems↗

Modulation Classification of Satellite Communication Signals Using Cumulants and Neural Networks

National Aeronautics and Space Administration (NASA)'s future communication architecture is evaluating cognitive technologies and increased system intelligence. These technologies are expected to reduce the operational complexity of the network, increase science data return, and reduce interference to self and others. In order to increase situational awareness, signal classification algorithms could be applied to identify users and distinguish sources of interference. A significant amount of previous work has been done in the area of automatic signal classification for military and commercial applications. As a preliminary step, we seek to develop a system with the ability to discern signals typically encountered in satellite communication. Proposed is an automatic modulation classifier which utilizes higher order statistics (cumulants) and an estimate of the signal-to-noise ratio. These features are extracted from baseband symbols and then processed by a neural network for classification. The modulation types considered are phase-shift keying (PSK), amplitude and phase-shift keying (APSK),and quadrature amplitude modulation (QAM). Physical layer properties specific to the Digital Video Broadcasting - Satellite- Second Generation (DVB-S2) standard, such as pilots and variable ring ratios, are also considered. This paper will provide simulation results of a candidate modulation classifier, and performance will be evaluated over a range of signal-to-noise ratios, frequency offsets, and nonlinear amplifier distortions.

Signal Recognition↗

Modulation Classification of Satellite Communication Signals Using Cumulants and Neural Networks

National Aeronautics and Space Administration (NASA)'s future communication architecture is evaluating cognitive technologies and increased system intelligence. These technologies are expected to reduce the operational complexity of the network, increase science data return, and reduce interference to self and others. In order to increase situational awareness, signal classification algorithms could be applied to identify users and distinguish sources of interference. A significant amount of previous work has been done in the area of automatic signal classification for military and commercial applications. As a preliminary step, we seek to develop a system with the ability to discern signals typically encountered in satellite communication. Proposed is an automatic modulation classifier which utilizes higher order statistics (cumulants) and an estimate of the signal-to-noise ratio. These features are extracted from baseband symbols and then processed by a neural network for classification. The modulation types considered are phase-shift keying (PSK), amplitude and phase-shift keying (APSK),and quadrature amplitude modulation (QAM). Physical layer properties specific to the Digital Video Broadcasting - Satellite- Second Generation (DVB-S2) standard, such as pilots and variable ring ratios, are also considered. This paper will provide simulation results of a candidate modulation classifier, and performance will be evaluated over a range of signal-to-noise ratios, frequency offsets, and nonlinear amplifier distortions.

Signal Classification↗