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The design, construction, and testing of a complete system to produce karyotypes and chromosome measurement data from human blood samples, and a basis for statistical analysis of quantitative chromosome measurement data is described. The prototype was assembled, tested, and evaluated on clinical material and thoroughly documented.
This article discusses the wide range of efforts being pursued by NASA to maintain the preeminence of the United States in military and commercial aircraft design. Emphasis is placed on the question of where industry should concentrate its research and technology efforts to support the aviation needs of the future. The major military and civil aircraft developments forseen for the period from 1985 to 2000 are identified, and NASA's role in the Highly Maneuverable Aircraft Technology program is briefly considered. Other programs discussed include those concerning airfoils, propulsion systems, aviation safety, next-generation subsonic transports, STOL and VTOL vehicles, and supersonic cruise aircraft.
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Very high resolution imaging provides the best means of examining geological processes acting on asteroid surfaces. Imaging also may be important for revealing how asteroids accreted and for obtaining some data on their differentiation history. Imaging from rendezvous together with Doppler tracking is the only way to determine accurate densities and hence place limits on bulk composition.
The survey needs of the U.S. Department of Agriculture are immense, ranging from individual crop coverage at specific intervals to general land use classification. The aggregate of all desirable resolutions and sensor types applicable to airborne platforms yields an annual survey coverage rate equivalent to about 6 times the U.S. land area. An intermediate annual survey level equal to the U.S. area can meet all currently perceived crop survey needs and provide sample imagery over many other resource areas. This decreased survey level can be accomplished with one or two high altitude aircraft or medium altitude aircraft. Survey costs range from about 25 cents to several dollars per square nautical mile depending primarily on resolution requirements and the aircraft used.
The survey needs of the U.S. De pa rtment of Agriculture are immense, ranging from individual crop coverage at specific intervals to general land use classification. The aggregate of all desirable resolutions and sensor types applicable to airborne platforms yields an annual survey coverage rate eqivalent to about 6 times the U.S. land area. An intermediate annual survey level equal to the U. S. area can meet all currently perceived crop survey needs and provide sample imagery over many other resource areas. This decreased survey level can be accomplished with one or two high altitude aircraft (e.g., U-2 or WB-57) or medium altitude aircraft ( such as the Learjet or Jetstar). Survey costs range from about 25 cents to several dollars per square nautical mile depending primarily on resolution requirements and the aircraft used.
There are not author-identified significant results in this report.
The thermionic and Brayton reactor concepts were compared for application to space power. For a turbine inlet temperature of 15000 K the Brayton powerplant weighted 5 to 40% less than the thermionic concept. The out of core concept separates the thermionic converters from their reactor. Technical risks are diminished by: (1) moving the insolator out of the reactor; (2) allowing a higher thermal flux for the thermionic converters than is required of the reactor fuel; and (3) eliminating fuel swelling's threat against lifetime of the thermionic converters. Overall performance can be improved by including power processing in system optimization for design and technology on more efficient, higher temperature power processors. The thermionic reactors will be larger than those for competitive systems with higher conversion efficiency and lower reactor operating temperatures. It is concluded that although the effect of reactor size on shield weight will be modest for unmanned spacecraft, the penalty in shield weight will be large for manned or man-tended spacecraft.
A description is given of current work in the development of sensors, and their integration into increasingly powerful systems, for oceanic phytoplankton abundance estimation. Among the problems relevant to such work are phytoplankton ecology, the spatial and temporal domains, available sensor platforms, and sensor combinations. Among the platforms considered are satellites, aircraft, tethered balloons, helicopters, ships, and the Space Shuttle. Sensors discussed include microwave radiometers, laser fluorosensors, microwave scatterometers, multispectral scanners, Coastal Ocean Dynamics Radar (CODAR), and linear array detectors. Consideration is also given to the prospects for such future sensor systems as the National Oceanic Satellite System (NOSS) and the Airborne Integrated Mapping System (AIMS).
A 10 year game plan for transition to the operational system was developed in the State of Washington. The plan is to: examine the results of past demonstration projects to identify successful operational applications, take advantage of geographic information systems, and work toward reducing/eliminating constraints of the present system which inhibit operational use. Support for the LANDSAT program was demonstrated by sending a user representative to NOAA working in the development of a user oriented system. It is suggested that the state should reassess its position, by taking advantage of the past 8 years' experience, and coordinate efforts to enhance LANDSAT' advantages in a cost effective manner.
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Automated interstellar space exploration is reviewed. The Titan demonstration mission is discussed. Remote sensing and automated modeling are considered. Nuclear electric propulsion, main orbiting spacecraft, lander/rover, subsatellites, atmospheric probes, powered air vehicles, and a surface science network comprise mission component concepts. Machine, intelligence in space exploration is discussed.
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Office automation (OA) steps being taken by NASA to improve efficiency in communications between centers and personnel are outlined. NASA centers are currently linked by satellite for electronic mail and scheduling through dumb and intelligent terminals. The implementation of teleconferencing with interactive graphics transmitted between dial-up terminals is being examined in a pilot program, and interactive data bases are already in operation, with an on-line summary data base being planned for NASA headquarters. The NASA Recon on-line service is operating with citations of over 2,200,000 aeronautics and astronautics research documents and 300,000 scientific books accessed by over 250 terminals around the U.S. The emphasis for all the OA systems is on user-friendly design and minimizing the required input for entry and access.
Aspects of the second Space Shuttle flight, which carried the first payload of scientific instruments for remote sensing of the earth's atmosphere, oceans, and land areas, are discussed. The development and integration of the payload, the mission simulations and end-to-end testing, the launch, the payload mission operations, the landing, data removal, and payload removal, the scientific results, and some planned experiments using the Shuttle are addressed. Summaries of the experimental results are presented, including those for the imaging radar, infrared radiometer, ocean color experiment, air pollution measurements, feature identification and location experiment, night/day optical lightning survey, and bioengineering test. The availability of data and science reports is also covered.
The solar cells in a photovoltaic module which must be electrically isolated from module exterior surfaces to satisfy a variety of safety and operating considerations are discussed. The performance and reliability of the insulation system are examined. Technical requirements involve the capability of withstanding the differential voltage from the solar cells to the module frame. The maximum system voltage includes consideration of maximum open circuit array voltages achieved under low-temperature, high-irradiance conditions, and transient overvoltages due to system feedback of lightning transients. The latter is bounded by the characteristics of incorporated voltage limiting devices such as MOVs.
The arbitrariness of the definition of life is discussed in relation to both the archaic biological entities that preceded cells during the Molecular Evolution era, and the hypothetical, primitive, 'living' entities that presumably can be synthesized in the laboratory. Several experimental approaches to the synthesis, detection, and characterization of 'living' entities are discussed. The experimental approaches considered for the synthesis are the constructionist strategy, the whole-environment strategy, and the modular strategy, which is a combination of the first two. The whole-environment strategy is discussed in more detail and the establishment of an Evolution Synthesizer, based on this strategy, is proposed and rationalized. The guidelines for the detection and characterization of populations and processes of 'living' entities include chemical and physical analyses, but are based mainly on the reproductive characterization of these entities. It is expected that the higher the evolutionary level of the 'living' entities, the longer and more difficult it will be to synthesize them, but the easier it will be to detect them.
The coupling of expert systems and control design and analysis techniques are documented to provide a realizable self repairing flight control system. Key features of such a flight control system are identified and a limited set of rules for a simple aircraft model are presented.