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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 487 records · Page 27

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NASA NTRS1977

Protecting proprietary rights - A potential Shuttle user's view

Maintaining a high degree of industrial security in the multiple-payload Shuttle environment poses a number of problems for NASA. As a part of Battelle-Columbus' support of NASA's User Development Program, this paper presents a potential user's perspective on this situation. The need for security, the nature of the problem, and precedents for NASA security measures are discussed. Eleven policy guidelines representing desirable features from a potential user's viewpoint are presented for NASA consideration.

Day, J. B.↗

NASA NTRS1978

The First Seasat-A Industrial Users Workshop

The purpose of this workshop was to begin the process of definition and development of the SEASAT-A Demonstration Program, leading to the implementation of a set of experiments which would begin during the latter part of 1978 following the launch of SEASAT-A (now scheduled for May 1978). NASA through the SEASAT-A program, has encouraged the planning of cooperative experiments by industry and government agencies that operate in areas of ocean activity that could benefit from improved measurements and forecasts of weather and ocean conditions. The objectives of these experiments are to: (1) evaluate the significance of SEASAT-A data to commercial user organizations; (2) assist in identifying those characteristics of follow-on systems that are important to industrial users; (3) obtain experimental evidence that could be used to refine estimates of the economic potential of an operational system; and (4) begin the technology transfer process to the industrial users.

Hicks, K. W.↗

NASA NTRS1978

NASCAP user's manual, 1978

NASCAP simulates the charging process for a complex object in either tenuous plasma (geosynchronous orbit) or ground test (electron gun source) environment. Program control words, the structure of user input files, and various user options available are described in this computer programmer's user manual.

Cassidy, J. J., III↗

NASA NTRS1977

Time determination for spacecraft users of the Navstar Global Positioning System /GPS/

Global Positioning System (GPS) navigation is performed by time measurements. A description is presented of a two body model of spacecraft motion. Orbit determination is the process of inferring the position, velocity, and clock offset of the user from measurements made of the user motion in the Newtonian coordinate system. To illustrate the effect of clock errors and the accuracy with which the user spacecraft time and orbit may be determined, a low-earth-orbit spacecraft (Seasat) as tracked by six Phase I GPS space vehicles is considered. The obtained results indicate that in the absence of unmodeled dynamic parameter errors clock biases may be determined to the nanosecond level. There is, however, a high correlation between the clock bias and the uncertainty in the gravitational parameter GM, i.e., the product of the universal gravitational constant and the total mass of the earth. It is, therefore, not possible to determine clock bias to better than 25 nanosecond accuracy in the presence of a gravitational error of one part per million.

Grenchik, T. J.↗

NASA NTRS1979

The 30/20 GHz mixed user architecture development study

A mixed-user system is described which provides cost-effective communications services to a wide range of user terminal classes, ranging from one or two voice channel support in a direct-to-user mode, to multiple 500 mbps trunking channel support. Advanced satellite capabilities are utilized to minimize the cost of small terminals. In a system with thousands of small terminals, this approach results in minimum system cost.

Source record↗

NASA NTRS1980

User's guide for the Flight Design System (FDS)

Information about the Flight Design System (FDS) in the context of flight design is presented. The guide introduces the FDS user to the structure of FDS and to constructs within FDS (such as files of information or the part of FDS which interacts directly with the user). A guide to the commands available to FDS users is presented. A glossary of important terms, an index to terms, and a quick reference to the commands of FDS are included.

Ramsey, H. R.↗

NASA NTRS1980

Thermal radiation analysis system TRASYS 2: User's manual

The Thermal Radiation Analyzer System (TRASYS) program put thermal radiation analysis on the same basis as thermal analysis using program systems such as MITAS and SINDA. The user is provided the powerful options of writing his own executive, or driver logic and choosing, among several available options, the most desirable solution technique(s) for the problem at hand. This User's Manual serves the twofold purpose of instructing the user in all applications and providing a convenient reference book that presents the features and capabilities in a concise, easy-to-find manner.

Goble, R. G.↗

NASA NTRS1980

User's manual for MMLE3, a general FORTRAN program for maximum likelihood parameter estimation

A user's manual for the FORTRAN IV computer program MMLE3 is described. It is a maximum likelihood parameter estimation program capable of handling general bilinear dynamic equations of arbitrary order with measurement noise and/or state noise (process noise). The theory and use of the program is described. The basic MMLE3 program is quite general and, therefore, applicable to a wide variety of problems. The basic program can interact with a set of user written problem specific routines to simplify the use of the program on specific systems. A set of user routines for the aircraft stability and control derivative estimation problem is provided with the program.

Maine, R. E.↗

NASA NTRS1981

FRANOPP: Framework for analysis and optimization problems user's guide

Framework for analysis and optimization problems (FRANOPP) is a software aid for the study and solution of design (optimization) problems which provides the driving program and plotting capability for a user generated programming system. In addition to FRANOPP, the programming system also contains the optimization code CONMIN, and two user supplied codes, one for analysis and one for output. With FRANOPP the user is provided with five options for studying a design problem. Three of the options utilize the plot capability and present an indepth study of the design problem. The study can be focused on a history of the optimization process or on the interaction of variables within the design problem.

Riley, K. M.↗

NASA NTRS1981

User requirements for NASA data base management systems. Part 1: Oceanographic discipline

Generic oceanographic user requirements were collected and analyzed for use in developing a general multipurpose data base management system for future missions of the Office of Space and Terrestrial Applications (OSTA) of NASA. The collection of user requirements involved; studying the state-of-the-art technology in data base management systems; analyzing the results of related studies; formulating a viable and diverse list of scientists to be interviewed; developing a presentation format and materials; and interviewing oceanographic data users. More effective data management systems are needed to handle the increasing influx of data.

Fujimoto, B.↗

NASA NTRS1982

The economics of time shared computing: Congestion, user costs and capacity

Time shared systems permit the fixed costs of computing resources to be spread over large numbers of users. However, bottleneck results in the theory of closed queueing networks can be used to show that this economy of scale will be offset by the increased congestion that results as more users are added to the system. If one considers the total costs, including the congestion cost, there is an optimal number of users for a system which equals the saturation value usually used to define system capacity.

Agnew, C. E.↗

NASA NTRS1983

User interface to administrative DRMS within a distributed environment

The implementation of a data base management system (DBMS) into a communications office to control and report on communication leased service contracts is discussed. The system user executes online programs to update five files residing on a UNIVAC 1100/82, through the forms mode features of the Tektronix 4025 terminal and IMSAI 8080 microcomputer. This user can select the appropriate form to the Tektronix 4025 screen, and enter new data, update existing data, or discontinue service. Selective online printing of 40 reports is accomplished by the system user to satisfy management, budget, and bill payment reporting requirements.

Martin, L. D.↗

NASA NTRS1982

Flight dynamics analysis and simulation of heavy lift airships. Volume 3: User's manual

The User's Manual provides the basic information necessary to run the programs. This includes descriptions of the various data files necessary for the program, the various outputs from the program and the options available to the user when executing the program. Additional data file information is contained in the three appendices to the manual. These appendices list all input variables and their permissible values, an example listing of these variables, and all output variables available to the user.

Emmen, R. D.↗

NASA NTRS1983

SEASAT synthetic-aperture radar data user's manual

The SEASAT Synthetic-Aperture Radar (SAR) system, the data processors, the extent of the image data set, and the means by which a user obtains this data are described and the data quality is evaluated. The user is alerted to some potential problems with the existing volume of SEASAT SAR image data, and allows him to modify his use of that data accordingly. Secondly, the manual focuses on the ultimate focuses on the ultimate capabilities of the raw data set and evaluates the potential of this data for processing into accurately located, amplitude-calibrated imagery of high resolution. This allows the user to decide whether his needs require special-purpose data processing of the SAR raw data.

Pravdo, S. H.↗

NASA NTRS1984

Action Information Management System (AIMS): a User's View

The initial approach used in establishing a user-defined information system to fulfill the needs of users at NASA Headquarters was unsuccessful in bringing this pilot endeaveor to full project status. The persistence of several users and the full involvement of the Ames Research Center were the ingredients needed to make the AIMS project a success. The lesson learned from this effort is that NASA should always work from its organizational strengths as a Headquarters-Center partnership.

Wiskerchen, M.↗

NASA NTRS1984

Pilot climate data system user's guide

Instructions for using the Pilot Climate Data System (PCDS), an interactive, scientific data management system for locating, obtaining, manipulating, and displaying climate-research data are presented. The PCDS currently provides this supoort for approximately twenty data sets. Figures that illustrate the terminal displays which a user sees when he/she runs the PCDS and some examples of the output from this system are included. The capabilities which are described in detail allow a user to perform the following: (1) obtain comprehensive descriptions of a number of climate parameter data sets and the associated sensor measurements from which they were derived; (2) obtain detailed information about the temporal coverage and data volume of data sets which are readily accessible via the PCDS; (3) extract portions of a data set using criteria such as time range and geographic location, and output the data to tape, user terminal, system printer, or online disk files in a special data-set-independent format; (4) access and manipulate the data in these data-set-independent files, performing such functions as combining the data, subsetting the data, and averaging the data; and (5) create various graphical representations of the data stored in the data-set-independent files.

Reph, M. G.↗

NASA NTRS1982

TDM/FM/FDMA - A modulation technique for multiple-beam satellites which precludes cochannel interference and allows non-uniform geographic distribution of user channels

The technique outlined in this paper is intended to eliminate the problems of cochannel interference and uniform geographic distribution of user channels which arise in conventional designs for a multiple spot beam communication satellite to serve mobile telephony users across the CONUS. By time multiplexing FM/FDMA signal ensembles so that only those beams operating on distinct frequency subbands are allowed to transmit concurrently, cochannel interference arising from simultaneous frequency subband reuse is precluded. Thus, time disjoint frequency reuse is accomplished over a repetitive sequence of fixed time slots. By assigning different size subbands to each time slot, a market of nonuniform users can be accommodated. The technique results in a greatly simplified antenna feed system design for the satellite, at a cost of imposing the need for time slot synchronization on the mobile FM receivers whose ability for rejecting adjacent channel interference is somewhat diminished.

Springett, J. C.↗

NASA NTRS1984

Space Telescope Control System science user operations

The Space Telescope science users will have a flexible and efficient means of accessing the capabilities provided by the ST Pointing Control System, particularly with respect to managing the overal acquisition and pointing functions. To permit user control of these system functions - such as vehicle scanning, tracking, offset pointing, high gain antenna pointing, solar array pointing and momentum management - a set of special instructions called 'constructs' is used in conjuction with command data packets. This paper discusses the user-vehicle interface and introduces typical operational scenarios.

Dougherty, H. J.↗