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A review is given of currently accepted theories and applications of gnotobiology. A brief history of gnotobiology is supplied. Problems involved in creating germ-free gnotobiota and the use of these animals in experimental biology are cited. Examples of how gnotobiology is used in modern medical practice illustrate the future prospects for this area of science.
The surfaces of the earth and the other terrestrial planets of the inner solar system are reviewed in light of the results of recent planetary explorations. Past and current views of the origin of the earth, moon, Mercury, Venus and Mars are discussed, and the surface features characteristic of the moon, Mercury, Mars and Venus are outlined. Mechanisms for the modification of planetary surfaces by external factors and from within the planet are examined, including surface cycles, meteoritic impact, gravity, wind, plate tectonics, volcanism and crustal deformation. The origin and evolution of the moon are discussed on the basis of the Apollo results, and current knowledge of Mercury and Mars is examined in detail. Finally, the middle periods in the history of the terrestrial planets are compared, and future prospects for the exploration of the inner planets as well as other rocky bodies in the solar system are discussed.
Several photoreactions for transducing light energy have been analyzed for their relevance as models for protocellular photophosphorylation. Inorganic ions and compounds could have played a role in protocellular photophosphorylation. Organic catalysts may have been the next significant agents used by protocells for photophosphorylation. Membranous photophosphorylation probably became the most recent type of photoenergy transduction to be acquired by protocells; it is still used by modern cells although components of the other types of phosphorylation are found in present day cells. Recorded yields of energy-rich phosphates from the model reactions discussed are small. Arguments are advanced that such yields could have been sufficient to have fueled protocellular metabolism, which was probably very slow compared to modern cellular metabolism. Future prospects for research in this area are discussed.
The use of telemetry to monitor various physiological functions is discussed. The advantages of the technique and the parameters that it can monitor are assessed, and the main telemetry systems, including pressure telemetry, flow telemetry, and multichannel telemetry, are detailed. Human applications of implanted flow transducers, total implant versus backpack telemetry, the use of power sources and integrated circuits in telemetry, and the future prospects of the technique in hypertension treatment and research are discussed.
Several aspects of LTA (lighter-than-air) technology development are reviewed. Technological developments of classical airships through 1974 are examined. A brief historical and technological summary of five specialized LTA equipment concepts is presented: metal-clad airships, free balloons, semibuoyant vehicles, high-altitude platforms, and tethered aerostats. Current LTA technology developments are reviewed with particular emphasis on VTOL airships capable of heavy lift and on long endurance types for coastal maritime patrol. Finally, the future prospects of LTA system development are considered with attention given to manned conventional and hybrid vehicles, tethered vehicles, and RPVs.
The role of computational aerodynamics in design is reviewed with attention given to the design process; the proper role of computations; the importance of calibration, interpretation, and verification; the usefulness of a given computational capability; and the marketing of new codes. Examples of computational aerodynamics in design are given with particular emphasis on the Highly Maneuverable Aircraft Technology. Finally, future prospects are noted, with consideration given to the role of advanced computers, advances in numerical solution techniques, turbulence models, complex geometries, and computational design procedures. Previously announced in STAR as N82-33348
The past-achievements, current status, and future prospects of the Landsat terrestrial-remote-sensing satellite program are surveyed. Topics examined include the early history of space flight; the development of analysis techniques to interpret the multispectral images obtained by Landsats 1, 2, and 3; the characteristics of the advanced Landsat-4 Thematic Mapper; microwave scanning by Seasat and the Shuttle Imaging Radar; the usefulness of low-resolution AVHRR data from the NOAA satellites; improvements in Landsats 4 and 5 to permit tailoring of information to user needs; expansion and internationalization of the remote-sensing market in the late 1980s; and technological advances in both instrumentation and data-processing predicted by the 1990s.
Computational fluid dynamics (CFD) is maturing, and is at a stage in its technological life cycle in which it is now routinely applied to some rather complicated problems; it is starting to create an impact on the design cycle of aerospace flight vehicles and their components. CFD is also being used to better understand the fluid physics of flows heretofore not understood, such as three-dimensional separation. CFD is also being used to complement and is being complemented by experiments. In this paper, the primary and secondary pacing items that govern CFD in the past are reviewed and updated. The future prospects of CFD are explored which will offer people working in the discipline challenges that should extend the technological life cycle to further increase the capabilities of a proven demonstrated technology.
Stellar X-ray astronomy represents an entirely new astronomical discipline which has emerged during the past five years. It lies at the crossroads of solar physics, stellar physics, and general astrophysics. The present review is concerned with the main physical problems which arise in connection with a study of the stellar X-ray data. A central issue is the extent to which the extrapolation from solar physics is justified and the definition (if possible) of the limits to such extrapolation. The observational properties of X-ray emission from stars are considered along with the solar analogy and the modeling of X-ray emission from late-type stars, the modeling of X-ray emission from early-type stars, the physics of stellar X-ray emission, stellar X-ray emission in the more general astrophysical context, and future prospects.
Project Cassini is concerned with a potential collaborative mission to Saturn and Titan. The project has been the subject of a joint ESA/NASA Technical Assessment Study from April 1984 to July 1985. The spacecraft consists of a Saturn Orbiter and a Titan entry Probe. Science objectives with respect to Titan include a determination of the abundances of atmospheric constituents and isotope ratios, a study of the distribution of trace gases, cloud physics, and a determination of the state of the surface. Other science objectives are related to Saturn, the rings, icy satellites, the magnetosphere of Saturn, and asteroids. Attention is given to mission design, the spacecraft, and future prospects.
Initial measurements on I-asterisk yields of alkyl iodides at 266 nm are reported using gain vs. absorption spectroscopy with an InGaAsP diode probe laser. The results are 102 percent + or - 4 percent, 102 percent + or - 7 percent, and 73 percent + or - 4 percent for n-C3F7I, i-C3F7I, and CH3I respectively. Future prospects for the development of diode laser systems and for their use in dynamical studies are discussed.
The current status and future prospects of the magnetoplasmadynamic (MPD) arcjet system are described. Recent research activities on the chemical rocket and electric propulsion are discussed. The characteristics of various MPD arcjet systems including the Komaba-I system developed by the Institute of Space and Astronautical Science of the Tokyo University are analyzed. The applications of the MPD arcjet system to the satellite test, lunar mission, free flyer test, space station test, and heliospheric exploration are discussed.
This is an introduction to this part of the proceedings and an overview of coronal diagnostics. The current understanding of coronal loops is summarized. Included are observations from ground-based radio telescopes and from X ray telescopes lofted above the atmosphere, as well as theoretical interpretations of these observations. Also included in these introductory remarks is a discussion of the three dimensional structure of coronal loops. Alternative radiation mechanisms are then described within the context of both the radio and X ray emission. Various methods of determining the strength and structure of the coronal magnetic field are then described, followed by the coronae of nearby stars and future prospects for radio diagnostic of coronal loops.
Workshop members devoted the majority of time to discussing future prospects for technology support of photovoltaic applications. Photovoltaics has provided power for almost every spacecraft launched in the free world in the last 25 years. Over this time, photovoltaics has demonstrated impressive growth in power level, operating lifetime and specific power (W/kg and W/square m). Yet, the current attitude toward this reliable form of space power generation is likely to preclude further dramatic performance gains.
The NASA Deep Space Network, a precision telecommunications and radio navigation facility, is described in detail. The first spacecraft relativity test with Mariner 6 and Mariner 7 at solar conjunction is discussed as well as more accurate tests using the Mariner 9 anchored to Mars. Consideration is also given to solar system tests of relativistic celestial mechanics and future prospects. It is noted that the NASA Mars Observer orbital mission is under development and is expected to reach Mars in 1991.
The potential of infrared forbidden emission lines for studying nebular abundances is discussed, with emphasis on the far-infrared fine-structure lines of oxygen and nitrogen. Observations of these transitions provide fundamentally new diagnostics of the physical conditions in ionized nebulae, and make it possible for the first time to study the abundances of these species in the inner parts of the Galaxy. These new tools for nebular abundance studies are only beginning to be exploited. The results derived so far from such studies are reviewed, and future prospects and applications of these techniques are discussed.
Paper reviews development of computational fluid dynamics and explores future prospects of technology. Report covers such topics as computer technology, turbulence, development of solution methodology, developemnt of algorithms, definition of flow geometries, generation of computational grids, and pre- and post-data processing.
Computational fluid dynamics (CFD) is maturing, and is at a stage in its technological life cycle where it is now routinely applied to complex problems. It is starting to create an impact on the design cycle of aerospace flight vehicles and their components. CFD is also being used to better understand the fluid physics of flows heretofore not understood, such as three-dimensional separation. CFD is also being used to complement and is complemented by experiments. In this paper, the primary and secondary pacing items that have governed CFD in the past are reviewed and updated. The future prospects of CFD are explored, which will offer people working in the discipline challenges that should extend the technological life cycle to further increase the capabilities of a proven and demonstrated technology.