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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 271 records · Page 15
All sourcesNASA NTRSDOE OSTI
NASA NTRS1993

Gravitational microlensing of gamma-ray bursts

A Monte Carlo code is developed to calculate gravitational microlensing in three dimensions when the lensing optical depth is low or moderate (not greater than 0.25). The code calculates positions of microimages and time delays between the microimages. The majority of lensed gamma-ray bursts should show a simple double-burst structure, as predicted by a single point mass lens model. A small fraction should show complicated multiple events due to the collective effects of several point masses (black holes). Cosmological models with a significant fraction of mass density in massive compact objects can be tested by searching for microlensing events in the current BATSE data. Our catalog generated by 10,000 Monte Carlo models is accessible through the computer network. The catalog can be used to take realistic selection effects into account.

Mao, Shude↗
NASA NTRS1992

Sensor fusion V; Proceedings of the Meeting, Boston, MA, Nov. 15-17, 1992

Topics addressed include 3D object perception, human-machine interface in multisensor systems, sensor fusion architecture, fusion of multiple and distributed sensors, interface and decision models for sensor fusion, computational networks, simple sensing for complex action, multisensor-based control, and metrology and calibration of multisensor systems. Particular attention is given to controlling 3D objects by sketching 2D views, the graphical simulation and animation environment for flexible structure robots, designing robotic systems from sensorimotor modules, cylindrical object reconstruction from a sequence of images, an accurate estimation of surface properties by integrating information using Bayesian networks, an adaptive fusion model for a distributed detection system, multiple concurrent object descriptions in support of autonomous navigation, robot control with multiple sensors and heuristic knowledge, and optical array detectors for image sensors calibration. (No individual items are abstracted in this volume)

Schenker, Paul S.↗
NASA NTRS1993

Features in the spectra of gamma-ray bursts

Gravitational lensing of cosmological gamma-ray bursts by objects in the mass range about 10 exp 17 to 10 exp 20 g (femtolensing) may introduce complicated interference patterns that might be interpreted as absorption or emission lines in the bursts' spectra. This phenomenon, if detected, may be used as a unique probe of dark matter in the universe. The BATSE spectral data should allow one to detect such spectral features or to put significant upper limits on the cosmic density of a dark matter component that may be in the femtolensing range. Software to generate theoretical spectra has been developed, and it is accessible over the computer network with anonymous ftp.

Stanek, Krzysztof Z.↗
NASA NTRS1988

A neurocomputing approach to model determination of large space structures

Viewgraphs on a neurocomputing approach to model determination of large space structures are presented. Topics covered include: background on neural networks; math modeling with neural networks; computer architectures for real-time modeling; and hardware and software implementation considerations, OPTIMA/1 data acquisition, modeling, and control workstation.

Travassos, Richard H.↗
NASA NTRS1993

NASA STI Program Coordinating Council Eleventh Meeting: NASA STI Modernization Plan

The theme of this NASA Scientific and Technical Information Program Coordinating Council Meeting was the modernization of the STI Program. Topics covered included the activities of the Engineering Review Board in the creation of the Infrastructure Upgrade Plan, the progress of the RECON Replacement Project, the use and status of Electronic SCAN (Selected Current Aerospace Notices), the Machine Translation Project, multimedia, electronic document interchange, the NASA Access Mechanism, computer network upgrades, and standards in the architectural effort.

Source record↗
NASA NTRS1994

The meteorological monitoring system for the Kennedy Space Center/Cape Canaveral Air Station

The Kennedy Space Center (KSC) and Cape Canaveral Air Station (CCAS) are involved in many weather-sensitive operations. Manned and unmanned vehicle launches, which occur several times each year, are obvious example of operations whose success and safety are dependent upon favorable meteorological conditions. Other operations involving NASA, Air Force, and contractor personnel, including daily operations to maintain facilities, refurbish launch structures, prepare vehicles for launch, and handle hazardous materials, are less publicized but are no less weather-sensitive. The Meteorological Monitoring System (MMS) is a computer network which acquires, processes, disseminates, and monitors near real-time and forecast meteorological information to assist operational personnel and weather forecasters with the task of minimizing the risk to personnel, materials, and the surrounding population. CLIPS has been integrated into the MMS to provide quality control analysis and data monitoring. This paper describes aspects of the MMS relevant to CLIPS including requirements, actual implementation details, and results of performance testing.

Dianic, Allan V.↗
NASA NTRS1995

NASA/DOD Aerospace Knowledge Diffusion Research Project. Paper 52: A comparison of the technical communications practices of Japanese and US aerospace engineers and scientists

To understand the diffusion of aerospace knowledge, it is necessary to understand the communications practices and the information-seeking behaviors of those involved in the production, transfer, and use of aerospace knowledge at the individual, organizational, national, and international levels. In this paper, we report selected results from a survey of Japanese and U.S. aerospace engineers and scientists that focused on communications practices and information-seeking behaviors in the workplace. Data are presented for the following topics: importance of and time spent communicating information, collaborative writing, need for an undergraduate course in technical communications, use of libraries, the use and importance of electronic (computer) networks, and the use and importance of foreign and domestically produced technical reports. The responses of the survey respondents are placed within the context of the Japanese culture. We assume that differences in Japanese and U.S. cultures influence the communications practices and information-seeking behaviors of Japanese and U.S. aerospace engineers and scientists.

Pinelli, Thomas E.↗
NASA NTRS1995

NASA/DOD Aerospace Knowledge Diffusion Research Project. Paper 54: The technical communications practices of engineering technology students: Results of the NASA/DOD Aerospace Knowledge Diffusion Research Project phase 3 student surveys

Engineering technology programs are characterized by their focus on application and practice, and by their approximately 50/50 mix of theory and laboratory experience. Engineering technology graduates are employed across the technological spectrum and are often found in areas that deal with application, implementation, and production. Yet we know very little about the communications practices and information-use skills of engineering technology students. In this paper, we report selected results of an exploratory study of engineering technology students enrolled in three U.S. institutions of higher education. Data are presented for the following topics: career goals and aspirations; the importance of, receipt of, and helpfulness of communications and information-use skills instruction; collaborative writing; use of libraries; and the use of electronic (computer) networks.

Pinelli, Thomas E.↗
NASA NTRS1995

Cloud Properties Derived From GOES-7 for Spring 1994 ARM Intensive Observing Period Using Version 1.0.0 of ARM Satellite Data Analysis Program

This document describes the initial formulation (Version 1.0.0) of the Atmospheric Radiation Measurement (ARM) program satellite data analysis procedures. Techniques are presented for calibrating geostationary satellite data with Sun synchronous satellite radiances and for converting narrowband radiances to top-of-the-atmosphere fluxes and albedos. A methodology is documented for combining geostationary visible and infrared radiances with surface-based temperature observations to derive cloud amount, optical depth, height, thickness, temperature, and albedo. The analysis is limited to two grids centered over the ARM Southern Great Plains central facility in north-central Oklahoma. Daytime data taken during 5 Apr. - 1 May 1994, were analyzed on the 0.3 deg and 0.5 deg latitude-longitude grids that cover areas of 0.9 deg x 0.9 deg and 10 deg x 14 deg, respectively. Conditions ranging from scattered low cumulus to thin cirrus and thick cumulonimbus occurred during the study period. Detailed comparisons with hourly surface observations indicate that the mean cloudiness is within a few percent of the surface-derived sky cover. Formats of the results are also provided. The data can be accessed through the World Wide Web computer network.

Minnis, Patrick↗
NASA NTRS1994

A PC based time domain reflectometer for space station cable fault isolation

Significant problems are faced by astronauts on orbit in the Space Station when trying to locate electrical faults in multi-segment avionics and communication cables. These problems necessitate the development of an automated portable device that will detect and locate cable faults using the pulse-echo technique known as Time Domain Reflectometry. A breadboard time domain reflectometer (TDR) circuit board was designed and developed at the NASA-JSC. The TDR board works in conjunction with a GRiD lap-top computer to automate the fault detection and isolation process. A software program was written to automatically display the nature and location of any possible faults. The breadboard system can isolate open circuit and short circuit faults within two feet in a typical space station cable configuration. Follow-on efforts planned for 1994 will produce a compact, portable prototype Space Station TDR capable of automated switching in multi-conductor cables for high fidelity evaluation. This device has many possible commercial applications, including commercial and military aircraft avionics, cable TV, telephone, communication, information and computer network systems. This paper describes the principle of time domain reflectometry and the methodology for on-orbit avionics utility distribution system repair, utilizing the newly developed device called the Space Station Time Domain Reflectometer (SSTDR).

Pham, Michael↗
NASA NTRS1996

A Comparison of the Technical Communications Practices of Japanese and U.S. Aerospace Engineers and Scientists

To understand the diffusion of aerospace knowledge, it is necessary to understand the communications practices and the information-seeking behaviors of those involved in the production, transfer, and use of aerospace knowledge at the individual, organizational, national, and international levels. In this paper, we report selected results from a survey of Japanese and U.S. aerospace engineers and scientists that focused on communications practices and information-seeking behaviors in the workplace. Data are presented for the following topics: importance of and time spent communicating information, collaborative writing, need for an undergraduate course in technical communications, use of libraries, the use and importance of electronic (computer) networks, and the use and importance of foreign and domestically produced technical reports. The responses of the survey respondents are placed within the context of the Japanese culture. We assume that differences in Japanese and U.S. cultures influence the communications practices and information-seeking behaviors of Japanese and U.S. aerospace engineers and scientists.

Pinelli, Thomas E.↗
NASA NTRS1997

NASA/DOD Aerospace Knowledge Diffusion Research Project. Paper 60: Culture and Workplace Communications: A Comparison of the Technical Communications Practices of Japanese and US Aerospace Engineers and Scientists

The advent of global markets elevates the role and importance of culture as a mitigating factor in the diffusion of knowledge and technology and in product and process innovation. This is especially true in the Large Commercial Aircraft (LCA) sector where the production and market aspects are becoming increasingly international. As firms expand beyond their national borders, using such methods as risk- sharing partnerships, joint ventures, outsourcing, and alliances, they have to contend with national and corporate cultures. Our focus is on Japan, a 'program participant' in the production of the Boeing Company's 777; the influence of Japanese culture on the diffusion of knowledge and technology in aerospace at the national and international levels; those cultural determinants-the propensity to work together, a willingness to subsume individual interests to a greater good, and an emphasis on consensual decisionmaking-that have a direct bearing on the ability of Japanese firms to form alliances and compete in international markets; and those cultural determinants thought to influence the information- seeking behaviors and workplace communication practices of Japanese aerospace engineers and scientists. In this paper, we report selective results from a survey of Japanese and U.S. aerospace engineers and scientists that focused on workplace communications. Data are presented for the following topics: importance of and time spent communicating information, collaborative writing, need for an undergraduate course in technical communication, use of libraries, use and importance of electronic (computer) networks, and the use and importance of foreign and domestically produced technical reports.

Pinelli, Thomas E.↗
NASA NTRS1997

NASA/DOD Aerospace Knowledge Diffusion Research Project. Paper 61: The Technical Communications Practices of ESL Aerospace Engineering Students in the United States: Results of a National Survey

When engineering students graduate and enter the world of work, they make the transition from an academic to a professional community of knowledge. The importance of oral and written communication to the professional success and advancement of engineers is well documented. For example, studies such as those conducted by Mailloux (1989) indicate that communicating data, information, and knowledge takes up as much as 80% of an engineer's time. However, these same studies also indicate that many engineering graduates cannot (a) write technical reports that effectively inform and influence decisionmaking, (b) present their ideas persuasively, and (c) communicate with their peers. If these statements are true, how is learning to communicate effectively in their professional knowledge community different for engineering students educated in the United States but who come from other cultures-cultures in which English is not the primary language of communication? Answering this question requires adequate and generalizable data about these students' communications abilities, skills, and competencies. To contribute to the answer, we undertook a national (mail) survey of 1,727 student members of the American Institute of Aeronautics and Astronautics (AIAA). The focus of our analysis and this paper is a comparison of the responses of 297 student members for whom English is a second language with the responses of 1,430 native English speaking students to queries regarding career choice, bilingualism and language fluency, communication skills, collaborative writing, computer use, and the use of electronic (computer) networks.

Webb, John R.↗
NASA NTRS1997

Innovative Educational Aerospace Research at the Northeast High School Space Research Center

Northeast High Magnet School of Philadelphia, Pennsylvania is a proud sponsor of the Space Research Center (SPARC). SPARC, a model program of the Medical, Engineering, and Aerospace Magnet school, provides talented students the capability to successfully exercise full simulations of NASA manned missions. These simulations included low-Earth Shuttle missions and Apollo lunar missions in the past, and will focus on a planetary mission to Mars this year. At the end of each scholastic year, a simulated mission, lasting between one and eight days, is performed involving 75 students as specialists in seven teams The groups are comprised of Flight Management, Spacecraft Communications (SatCom), Computer Networking, Spacecraft Design and Engineering, Electronics, Rocketry, Robotics, and Medical teams in either the mission operations center or onboard the spacecraft. Software development activities are also required in support of these simulations The objective of this paper is to present the accomplishments, technology innovations, interactions, and an overview of SPARC with an emphasis on how the program's educational activities parallel NASA mission support and how this education is preparing student for the space frontier.

Audra Luyet↗
NASA NTRS1997

NASA/DOD Aerospace Knowledge Diffusion Research Project. Paper 64: Culture and Workplace Communications: A Comparison of the Technical Communications Practices of Japanese and US Aerospace Engineers and Scientists

The advent of global markets elevates the role and importance of culture as a mitigating factor in the diffusion of knowledge and technology and in product and process innovation. This is especially true in the large commercial aircraft (LCA) sector where the production and market aspects are becoming increasingly international. As firms expand beyond their national borders, using such methods as risk-sharing partnerships, joint ventures, outsourcing, and alliances, they have to contend with national and corporate cultures. Our focus is on Japan, a program participant in the production of the Boeing Company's 777. The aspects of Japanese culture and workplace communications will be examined: 1.) the influence of Japanese culture on the diffusion of knowledge and technology in aerospace at the national and international levels; 2.) those cultural determinants-the propensity to work together, a willingness to subsume individual interests to a greater good, and an emphasis on consensual decision making-that have a direct bearing on the ability of Japanese firms to form alliances and compete in international markets; 3.) and those cultural determinants thought to influence the information-seeking behaviors and workplace communication practices of Japanese aerospace engineers and scientists. In this article, we report selective results from a survey of Japanese and U.S. aerospace engineers and scientists that focused on workplace communications. Data are presented for the following topics: importance of and time spent communicating information, collaborative writing, need for an undergraduate course in technical communication, use of libraries, use and importance of electronic (computer) networks, and the use and importance of foreign and domestically produced technical reports.

Pinelli, Thomas E.↗
NASA NTRS1997

Buckets, Clusters and Dienst

In this paper we describe NCSTRL+, a unified, canonical digital library for scientific and technical information (STI). NCSTRL+ is based on the Networked Computer Science Technical Report Library (NCSTRL), a World Wide Web (WWW) accessible digital library (DL) that provides access to over 80 university departments and laboratories. NCSTRL+ implements two new technologies: cluster functionality and publishing "buckets." We have extended the Dienst protocol, the protocol underlying NCSTRL, to provide the ability to "cluster" independent collections into a logically centralized digital library based upon subject category classification, type of organization, and genres of material. The concept of "buckets" provides a mechanism for publishing and managing logically linked entities with multiple data formats. The NCSTRL+ prototype DL contains the holdings of NCSTRL and the NASA Technical Report Server (NTRS). The prototype demonstrates the feasibility of publishing into a multi-cluster DL, searching across clusters, and storing and presenting buckets of information. We show that the overhead for these additional capabilities is minimal to both the author and the user when compared to the equivalent process within NCSTRL.

Nelson, Michael L.↗
NASA NTRS1997

Culture and Workplace Communications: A Comparison of the Technical Communications Practices of Japanese and U.S. Aerospace Engineers and Scientists

The advent of global markets elevates the role and importance of culture as a mitigating factor in the diffusion of knowledge and technology and in product and process innovation. This is especially true in the large commercial aircraft (LCA) sector where the production and market aspects are becoming increasingly international. As firms expand beyond their national borders, using such methods as risk-sharing partnerships, joint ventures, outsourcing, and alliances, they have to contend with national and corporate cultures. Our focus is on Japan, a program participant in the production of the Boeing Company's 777. The aspects of Japanese culture and workplace communications will be examined: (1) the influence of Japanese culture on the diffusion of knowledge and technology in aerospace at the national and international levels; (2) those cultural determinants-the propensity to work together, a willingness to subsume individual interests to a greater good, and an emphasis on consensual decision making-that have a direct bearing on the ability of Japanese firms to form alliances and compete in international markets; (3) and those cultural determinants thought to influence the information-seeking behaviors and workplace communication practices of Japanese aerospace engineers and scientists. In this article, we report selective results from a survey of Japanese and U.S. aerospace engineers and scientists that focused on workplace communications. Data are presented for the following topics: importance of and time spent communicating information, collaborative writing, need for an undergraduate course in technical communication, use of libraries, use and importance of electronic (computer) networks, and the use and importance of foreign and domestically produced technical reports.

Pinelli, Thomas E.↗
NASA NTRS1998

Creating a Canonical Scientific and Technical Information Classification System for NCSTRL+

The purpose of this paper is to describe the new subject classification system for the NCSTRL+ project. NCSTRL+ is a canonical digital library (DL) based on the Networked Computer Science Technical Report Library (NCSTRL). The current NCSTRL+ classification system uses the NASA Scientific and Technical (STI) subject classifications, which has a bias towards the aerospace, aeronautics, and engineering disciplines. Examination of other scientific and technical information classification systems showed similar discipline-centric weaknesses. Traditional, library-oriented classification systems represented all disciplines, but were too generalized to serve the needs of a scientific and technically oriented digital library. Lack of a suitable existing classification system led to the creation of a lightweight, balanced, general classification system that allows the mapping of more specialized classification schemes into the new framework. We have developed the following classification system to give equal weight to all STI disciplines, while being compact and lightweight.

Tiffany, Melissa E.↗