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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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Three-volume reference work serves as catalog of analysis techniques for elastic and inelastic stress ranges and as source on background and development of methods. Information is condensation of published journal articles, industry and university publications, textbooks, and government documents.
The Moon and its relation to the Earth and Sun have been observed by men from ancient times to the present with ever-increasing intensity and effectiveness. Results of these studies up to the most recent years have been recorded in numerous treatises and textbooks. For present purposes, it is not necessary to review the older work, which will be referred to without detailed discussion whenever it bears on very recent work.
The major results in structural synthesis and design which are now available in textbook form are discussed which suggests a number of promising directions for future research.
Results are reported for Copernicus observations of the double-lined binary V Puppis in the wavelength region from 1155 to 1310 A with a resolution of 0.2 A. The sharp-lined UV absorption spectrum is found to provide a line of sight dominated by an apparently 'textbook' H II region in a Stromgren sphere surrounding the stars. Several characteristics of this H II region are deduced by analyzing absorption features arising from excited fine-structure states of N II and Si II. Evidence is given for the presence of a normal interstellar H I region containing H2 and a separate H I region which could be the transition zone of the H II region. A possible blueshifted N V feature is noted in absorption. It is suggested that the H(+) emission measure and a characteristic size and shape for the H II region can probably be determined by optical observations of Balmer recombination lines within about 1 deg of V Puppis.
The goals of the Apollo-Soyuz Test Project are described in this first in a series of nine pamphlets designed as a curriculum supplement for teachers, supervisors, curriculum specialists, and textbook writers as well as for the general public. Aspects of the space flight covered include descriptions of the astronaut-cosmonaut meeting and of the spacecraft and landing module; spacecraft launch; control, and rendezvous; crew work schedule; and telemetry. Experiments performed are listed in tables, and their major results are summarized.
A textbook prepared primarily for use in introductory courses in remote sensing is presented. Topics covered include concepts and foundations of remote sensing; elements of photographic systems; introduction to airphoto interpretation; airphoto interpretation for terrain evaluation; photogrammetry; radiometric characteristics of aerial photographs; aerial thermography; multispectral scanning and spectral pattern recognition; microwave sensing; and remote sensing from space.
The question, "What is Technical Writing?", is addressed. Interest about the stance a teacher assumes in a classroom, the orientation of textbooks, and the shape of curricula are considered. Technical writing is considered of age, definitions abound and the time is ripe for a metaperspective on the question. This analyzes pitfalls in representative definitions of technical writing suggest a direction for future inquiry.
The standard distinction between poetic and referential language, the gulf between science and the humanities, and the distress many teachers of English feel when faced for the first time with the prospect of teaching technical writing are discussed. In the introduction of many technical writing textbooks. Technical communication is divorced from other forms of linguistic experience by making language limiting and reductive rather than creative and expansive. The emphasis on technical/scientific writing as radically different had blinded people to those traits it has in common with all species of composition and has led to a neglect of research, on fundamental rhetorical issues. A complete rhetorical theory of technical discourse should include information about the attitudes and motives of writers, the situations which motivate (or coerce) them to write, definitive features of technical style and form, interrelationship of expression and creativity, and functions of communication in shaping and preserving scientific networds and institutions. The previous areas should be explored with respect to contemporary practice and within an historical perspective.
A system designed to access a large range of available medical textbook information in an online interactive fashion is described. A high level query type database manager, INQUIRE, is used. Operating instructions, system flow diagrams, database descriptions, text generation, and error messages are discussed. User information is provided.
The contents of 17 major textbooks and reference guides on remote sensing technology are listed and compared. As a group, these books concentrate more on principles of the electromagnetic spectrum, sensors and data processing, than on applications. Secondly, it appears that basic photointerpretation receives considerable attention, but that photogrammetry does not. Four texts which provide well-rounded treatments of the systematics of remote sensing are suggested.
As the rate of energy release in a double layer with voltage delta V is P approx I delta V, a double layer must be treated as a part of a circuit which delivers the current I. As neither double layer nor circuit can be derived from magnetofluid models of a plasma, such models are useless for treating energy transfer by means of double layers. They must be replaced by particle models and circuit theory. A simple circuit is suggested which is applied to the energizing of auroral particles, to solar flares, and to intergalactic double radio sources. Application to the heliospheric current systems leads to the prediction of two double layers on the Sun's axis which may give radiations detectable from Earth. Double layers in space should be classified as a new type of celestial object (one example is the double radio sources). It is tentatively suggested in X-ray and Gamma-ray bursts may be due to exploding double layers (although annihilation is an alternative energy source). A study of how a number of the most used textbooks in astrophysics treat important concepts like double layers, critical velocity, pinch effects and circuits is made.
Equations derived for input impedance, input power, and ratio of secondary current to primary current of rotary transformer. Used for quick analysis of transformer designs. Circuit model commonly used in textbooks on theory of ac circuits.
The knowledge engineering and rapid prototyping phases of an expert system that does fault handling for a Solid Amine, Water Desorbed CO2 removal assembly for the Environmental Control and Life Support System for space based platforms are addressed. The knowledge acquisition phase for this project was interesting because it could not follow the textbook examples. As a result of this, a variety of methods were used during the knowledge acquisition task. The use of rapid prototyping and the need for a flexible prototype suggested certain types of knowledge representation. By combining various techniques, a representative subset of faults and a method for handling those faults was achieved. The experiences should prove useful for developing future fault handling expert systems under similar constraints.
The fundamental aerodynamics of slender bodies is examined in the reprint edition of an introductory textbook originally published in 1960. Chapters are devoted to the formulas commonly used in missile aerodynamics; slender-body theory at supersonic and subsonic speeds; vortices in viscid and inviscid flow; wing-body interference; downwash, sidewash, and the wake; wing-tail interference; aerodynamic controls; pressure foredrag, base drag, and skin friction; and stability derivatives. Diagrams, graphs, tables of terms and formulas are provided.
The mechanics of the first adiabatic invariant mu of nonrelativistic charged particles in time-dependent magnetic inductions B (t) are studied by means of computer simulations and analytic theory. Linear-ramp magnetic-induction profiles are utilized, as well as hyperbolic-tangent ramps and sine half-wave ramps. The change in mu that results from an induction change Delta B that occurs over a time Delta t is quantified for all values of Delta B and Delta t, as well as for all values of the particle position. It is found that the cases fall into two categories with very different mu behavior: cases in which the change in the magnetic induction occurs over a time Delta t that is exactly equal to an integer number of gyroperiods (textbook case) or cases in which the change in the induction occurs over a time Delta t that is not equal to an integer number of gyroperiods (more general case). In both categories mu is an adiabatic invariant, although the conservation of mu is much poorer in the latter category.
The problem of electromagnetic field quantization is usually considered in textbooks under the assumption that the field occupies some empty box. The case when a nonuniform time-dependent dielectric medium is confined in some space region with time-dependent boundaries is studied. The basis of the subsequent consideration is the system of Maxwell's equations in linear passive time-dependent dielectric and magnetic medium without sources.
Although the problem of electromagnetic radiation by a quantum harmonic oscillator is considered in textbooks on quantum mechanics, some of its aspects have remained unclear until now. By this, we mean that usually the initial quantum states of both the oscillator and the field are assumed to be characterized by a definite energy level of the oscillator and definite occupation numbers of the field modes. In connection with growing interest in squeezed states, it would be interesting to analyze the general case when the initial states of both subsystems are arbitrary superpositions of energy eigenstates. This problem was considered in other work, where the power of the spontaneous emission was calculated in the case of an arbitrary oscillator's initial state, but the field was initially in a vacuum state. In the present article, we calculate the rate of the oscillator average energy, squeezing, and correlation parameter change under the influence of an arbitrary external radiation field. Some other problems relating to the interaction between quantum particles (atoms) or oscillators where the electromagnetic radiation is an arbitrary (in particular squeezed) state were investigated.
The goal of this project is to increase the scientific knowledge and appreciation bases and skills of pre-service and in-service middle school teachers, so as to impact positively on teaching, learning, and student retention. This report lists the objectives and summarizes the progress thus far. Included is the working draft of the TIMS (Teaching Integrated Math/Science) curriculum outline. Seven of the eight instructional subject-oriented modules are also included. The modules include informative materials and corresponding questions and educational activities in a textbook format. The subjects included here are the universe and stars; the sun and its place in the universe; our solar system; astronomical instruments and scientific measurements; the moon and eclipses; the earth's atmosphere: its nature and composition; and the earth: directions, time, and seasons. The module not included regards winds and circulation.