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This first in a series of cyclic oxidation handbooks contains specific-weight-change-versus-time data and X-ray diffraction results derived from high-temperature cyclic tests on high-temperature, high-strength nickel-base gamma/gamma' and cobalt-base turbine alloys. Each page of data summarizes a complete test on a given alloy sample.
The structure and initial work performed toward the creation of a handbook for workload analysis directed at the operational community of engineers and human factors psychologists are described. The goal, when complete, will be to make accessible to such individuals the results of theoretically-based research that are of practical interest and utility in the analysis and prediction of operator workload in advanced and existing systems. In addition, the results of laboratory study focused on the development of a subjective rating technique for workload that is based on psychophysical scaling techniques are described.
All NASA management directives in force as of August 1, 1984 are listed by major subject headings showing number, effective date, title, responsible office, and distribution code. Delegations of authority in print by that date are listed numerically as well as by the installation or office to which special authority is assigned. Other consolidated lists show all management handbooks, directives applicable to the Jet Propulsion Laboratory, directives published in the Code of Federal Regulations, complementary manuals, and NASA safety standards. Distribution policies and instructions for ordering directives are included.
The main material properties affecting the explosive weldability of a certain metal combination are the yield strength, the ductility, the density and the sonic velocity of the two metals. Successful welding of the metal combination depends mainly on the correct choice of the explosive welding parameters; i.e., the stand off distance, the weight of the explosive charge relative to the weight of the flyer plate and the detonation velocity of the explosive. Based on the measured and the handbook values of the properties of interest, the explosive welding parameters were calculated and the arrangements for the explosive welding of the Al alloy 6061-T6, titanium and zirconium to OFHC copper were determined. The relatively small sheet metal thickness (1/8") and the fact that the thickness of the explosive layer must exceed a certain minimum value were considered during the determination of the explosive welding conditions. The results of the metallographic investigations and the measurements of the shear strength at the interface demonstrate the usefulness of these calculations to minimize the number of experimental trials.
This work is an illustrated handbook containing the rationale and procedure for the evaluation of multilayer printed wiring board construction integrity with respect to plated-through holes in accordance with the requirements of MIL-P-55110D, Printed Wiring Boards. It is intended as a practical aid for those concerned with determining the construction integrity of multilayer boards for high reliability applications. Photomicrographs of cross sectioned holes illustrate defect types, acceptable and unacceptable conditions, and methods of measurement. A procedure for specimen preparation is given, and appropriate paragraphs of the military specification are included and explained.
The present paper proviees a listing of all of the English books and some of the foreign books on finite element technology, taking into account also a list of the conference proceedings devoted solely to finite elements. The references are divided into categories. Attention is given to fundamentals, mathematical foundations, structural and solid mechanics applications, fluid mechanics applications, other applied science and engineering applications, computer implementation and software systems, computational and modeling aspects, special topics, boundary element methods, proceedings of symmposia and conferences on finite element technology, bibliographies, handbooks, and historical accounts.
This paper discusses the development of handbook techniques for the preliminary assessment of V/STOL aircraft performance while hovering in the proximity of the ground. In particular, the suckdown forces due to entrainment are described for configurations using a single jet. Corrections to current methods are suggested from an analysis of recent large-scale test data.
The complete aircraft design process can be broken into three phases of increasing depth: conceptual design, preliminary design, and detail design. Conceptual design consists primarily of developing general arrangements and selecting the configuration that optimally satisfies all mission requirements. The result of the conceptual phase is a conceptual baseline configuration that serves as the starting point for the preliminary design phase. The conceptual design of an aircraft involves a complex trade-off of many independent variables that must be investigated before deciding upon the basic configuration. Some of these variables are discrete (number of engines), some represent different configurations (canard vs conventional tail) and some may represent incorporation of new technologies (aluminum vs composite materials). At Lockheed-Georgia, the sizing program is known as GASP (Generalized Aircraft Sizing Program). GASP is a large program containing analysis modules covering the many different disciplines involved fin defining the aricraft, such as aerodynamics, structures, stability and control, mission performance, and cost. These analysis modules provide first-level estimates the aircraft properties that are derived from handbook, experimental, and historical sources.
Temporal variation in earth-atmosphere system reflectance in the 0.5-1.1 micron waveband was determined from Landsat MSS data for an area of arid rangeland in south-central New Mexico. Data were extracted from eight MSS scenes for the period 1973-1983, with four scenes from 1976. Maximum potential change between the extremes of rangeland degradation status was estimated to provide a benchmark for assessing the significance of the observed variations. Reflectance standardized for differences in sensor radiometric response by the Environmental Research Institute of Michigan coefficients increased significantly from 1973 to 1983, but standardization by Landsat Data Users Handbook coefficients resulted in little long-term change. Short-term (less than 1 year) variation was significant relative to maximum potential change. A sequence of three Landsat-2 scenes within one year showed a decrease in reflectance with increasing solar zenith angle. The effect of zenith angle on shading of the soil surface by plants was estimated and found to be about the same magnitude as the observed within-year variation in reflectance with solar zenith angle.
NASA regulations require that formal risk analysis be performed on a program at each of several milestones as it moves toward full-scale development. Program risk analysis is discussed as a systems analysis approach, an iterative process (identification, assessment, management), and a collection of techniques. These techniques, which range from simple to complex network-based simulation were surveyed. A Program Risk Analysis Handbook was prepared in order to provide both analyst and manager with a guide for selection of the most appropriate technique.
This is the 18th issue of NASA's USSR Life Sciences Digest. It contains abstracts of 50 papers published in Russian language periodicals or presented at conferences and of 8 new Soviet monographs. Selected abstracts are illustrated with figures and tables from the original. A review of a recent Aviation Medicine Handbook is also included. The abstracts in this issue have been identified as relevant to 37 areas of space biology and medicine. These areas are: adaptation, aviation medicine, biological rhythms, biospherics, body fluids, cardiovascular and respiratory systems, cytology, developmental biology, endocrinology, enzymology, equipment and instrumentation, exobiology, gastrointestinal system, genetics, gravitational biology, group dynamics, habitability and environmental effects, hematology, human performance, immunology, life support systems, man-machine systems, mathematical modeling, metabolism, microbiology, musculoskeletal system, neurophysiology, nutrition, operational medicine, perception, personnel selection, psychology, radiobiology, reproductive biology, space biology and medicine, and space industrialization.
The X- and S-band system operating noise temperatures of the Deep Space Network (DSN) 70-m antennas are presented. Models of atmosphere and ground noise temperature contributions, as they affect the antenna calibrations, are given for future use in telecommunications link modeling. The measured 70-m antenna network gain/system noise temperature (G/T) performance is presented. Compared with the earlier 64-m antenna network, G/T improvements of from 1.8 dB to 2.5 dB, depending on elevation angle, were achieved. G/T comparisons are made with the DSN/Flight Project Design Handbook and the Voyager telecommunications design control table. Actual Voyager telecommunications link performance is compared with predictions made by TPAP (the Voyager telecommunications prediction and analysis program) and with measured performance of the individual 70-m antennas. A modification in the use of antenna gain, system noise temperature, and atmospheric attenuation in existing telecommunications design control tables is suggested.
NASA has recently established a maintainability and maintenance planning program. This paper presents an overview of the program and discusses the specific application of the maintainability requirements as contained in NASA handbook (NHB) 5300.4 (1E), 'Maintainability Program Requirements for Space Systems'. Suggestions regarding the extent to which these requirements should be applied during each phase of program development also are presented.
Statistics are emphasized as an important role in quality control and reliability. Consequently, Trend Analysis Techniques recommended a variety of statistical methodologies that could be applied to time series data. The major goal of the working handbook, using data from the MSFC Problem Assessment System, is to illustrate some of the techniques in the NASA standard, some different techniques, and to notice patterns of data. Techniques for trend estimation used are: regression (exponential, power, reciprocal, straight line) and Kendall's rank correlation coefficient. The important details of a statistical strategy for estimating a trend component are covered in the examples. However, careful analysis and interpretation is necessary because of small samples and frequent zero problem reports in a given time period. Further investigations to deal with these issues are being conducted.
This is the twenty-fifth issue of NASA's Space Life Sciences Digest. It contains abstracts of 30 journal papers or book chapters published in Russian and of 2 Soviet monographs. Selected abstracts are illustrated with figures and tables from the original. The abstracts in this issue have been identified as relevant to 18 areas of space biology and medicine. These areas include: adaptation, aviation medicine, biological rhythms, biospherics, botany, cardiovascular and respiratory systems, endocrinology, enzymology, exobiology, habitability and environmental effects, hematology, immunology, metabolism, musculoskeletal system, neurophysiology, radiobiology, and space medicine. A Soviet book review of a British handbook of aviation medicine and a description of the work of the division on aviation and space medicine of the Moscow Physiological Society are also included.
The description of single event upsets (SEUs) in the spacecraft Anomalies Handbook is reviewed. The basic mechanism involved in SEUs is summarized and discussed in terms of circuit analysis. Calculation of SEU rate is analytically described and discussed. Departures from single step function dependence in the SEU rate is addressed.
Discussed are a variety of remotely sensed data sources that may have utility in the identification of conservation practices and related linear features. Test sites were evaluated in Alabama, Kansas, Mississippi, and Oklahoma using one or more of a variety of remotely sensed data sources, including color infrared photography (CIR), LANDSAT Thematic Mapper (TM) data, and aircraft-acquired Thermal Infrared Multispectral Scanner (TIMS) data. Both visual examination and computer-implemented enhancement procedures were used to identify conservation practices and other linear features. For the Kansas, Mississippi, and Oklahoma test sites, photo interpretations of CIR identified up to 24 of the 109 conservation practices from a matrix derived from the SCS National Handbook of Conservation Practices. The conservation practice matrix was modified to predict the possibility of identifying the 109 practices at various photographic scales based on the observed results as well as photo interpreter experience. Some practices were successfully identified in TM data through visual identification, but a number of existing practices were of such size and shape that the resolution of the TM could not detect them accurately. A series of computer-automated decorrelation and filtering procedures served to enhance the conservation practices in TM data with only fair success. However, features such as field boundaries, roads, water bodies, and the Urban/Ag interface were easily differentiated. Similar enhancement techniques applied to 5 and 10 meter TIMS data proved much more useful in delineating terraces, grass waterways, and drainage ditches as well as the features mentioned above, due partly to improved resolution and partly to thermally influenced moisture conditions. Spatially oriented data such as those derived from remotely sensed data offer some promise in the inventory and monitoring of conservation practices as well as in supplying parameter data for a variety of computer-implemented agricultural models.
This handbook is designed to promote a better understanding of NASA's interests and the process of doing business with NASA. The document is divided into the following sections: (1) this is NASA; (2) the procurement process; (3) marketing your capabilities; (4) special assistance programs; (5) NASA field installations; (6) sources of additional help; (7) listing of NASA small/minority business personnel; and (8) NASA organization chart.