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Portable machine constructed for fatigue testing of structural materials or machinery parts subjected to fatigue loads. Piezoelectric crystal stack adds oscillatory force to constant force. Machine tests wider variety of objects than with usual rotating-beam fatigue tests.
Tool with stepped shoulders alines tubes for machining in preparation for welding. Alinement with machine tool axis accurate to within 5 mils (0.13mm) and completed much faster than visual setup by machinist.
The machine-readable data set is the result of an objective-prism survey made with an 80 cm/120 cm Schmidt telescope. The F2 and earlier stars were isolated from later type objects by using the MK classification criteria. The catalog contains 601 stars and includes cross identifications to the BD and HD catalogs, coordinates, photographic magnitudes and spectral types. A separate file contains the remarks from the original data tables merged with those following the data. The machine-readable files are described.
The contents and format of the machine-readable version of the cataloque distributed by the Astronomical Data Center are described. Coding for the various scales and abbreviations used in the catalogue are tabulated and certain revisions to the machine version made to improve storage efficiency and notation are discussed.
Modifications, corrections, and the record format are provided for the machine-readable version of the "Morphological Catalogue of Galaxies.' In addition to hundreds of individual corrections, a detailed comparison of the machine-readable with the published catalogue resulted in the addition of 116 missing objects, the deletion of 10 duplicate records, and a format modification to increase storage efficiency.
The External Fuel Tank (ET) of the Space Shuttle is not recovered after launch and a new one must be provided for each launch. Currently, the external ""skin'' panels of the tank are produced by machining from solid wrought 2219-T87 aluminum plate stock approximately 1-3/4 inch thick. The reduction of costs in producing External Fuel Tank panels is obviously of increasing production rates and decreasing costs of the panels through the application of high-speed machining (HSM) techniques was conducted.
The length, or size (in number of Source Lines of Code) of programs represented as state machines, it is demonstrated, can be reliably estimated in terms of the number of internal state machine variables.
The Finite Element Machine is an experimental array processor designed to support research in parallel algorithms and architectures. This report presents a case study of communications using the SENDa and RECV system software routines on the Finite Element Machine, followed by a discussion of the effect of I/O performance on the efficiency of parallel algorithms.
This catalog contains a summary of many individual papers published in the Lowell Observatory Bulletins in the years 1958 to 1970. The data in the machine-readable version include observed positions, proper motions, estimated photographic magnitudes and colors, and references to identifications in other catalogs. Photoelectric data on the UBV system are included for many stars, but no attempt was made to find all existing photometry. The machine version contains all data of the published catalog, except the Lowell Bulletin numbers where finding charts can be found. A separate file contains the notes published in the original catalog.
A simplified model of the future is introduced in order to examine the relations between man, machine, and extraterrestrial intelligence. The observed lack of extraterrestrials on earth is used as a boundary condition for the model. Two exobiological conclusions are obtained: (1) advanced extraterrestrials exist but are difficult to observe or to distinguish from natural phenomena, (2) lower level, man-like extraterrestrials, which are potentially observable, are rare in the Universe because they are rapidly replaced in the evolutinary sequence by the intelligent machines which they create. The decline of man is inferred and may take place as soon as 100 years from now or as long as 100,000 years from the present time. Thus, we are a short-lived species, having a life expectancy of only a million years. A note is appended on the rationale and methods of the search for extraterrestrial intelligence in light of the above calculations. The Tau Ceti and Epsilon Eridani systems present favourable opportunities for a radio-search experiment in 1987 and 1988, respectively.
Flaps guard against flying chips, but fold away for tool setup. Clear plastic shield in position to intercept flying chips from machine tool and retracted to give operator access to workpiece. Machine shops readily make such shields for own use.
Interlock assures that workpiece is correctly assembled in machining fixture. A Plunger in a Hollow Shaft actuates a switch, allowing a power supply to produce current for electrical-discharge machining. Plunger operates only when necessary parts are position.
The machine readable catalogue contains survey data from the papers of Pilkington and Scott and Gower, Scott and Wills. These data result from a survey of radio sources between declinations -07 deg and +80 deg using the large Cambridge interferometer at 178 MHz. The computerized catalog contains for each source the 4C number, 1950 position, measured flux density, and accuracy class. For some sources miscellaneous brief comments such as cross identifications to the 3C catalog or remarks on contamination from nearby sources are given at the ends of the data records. A detailed description of the machine readable catalog as it is currently being distributed by the Astronomical Data Center is given to enable users to read and process the data.
The machine-readable catalog provides mean data on the old Slettebak system for 6472 stars. The catalog results from the review, analysis and transformation of 11460 data from 102 sources. Star identification, (major catalog number, name if the star has one, or cluster identification, etc.), a man projected rotational velocity, and a list of source references re included. The references are given in a second file included with the catalog when it is distributed on magnetic tape. The contents and/formats of the the data and reference files of the machine-readable catalog are described to enable users to read and process the data.
Actual and projected optimum High Speed Machining data for producing shuttle external tank liquid hydrogen barrel panels of aluminum alloy 2219-T87 are reported. The data included various machining parameters; e.g., spindle speeds, cutting speed, table feed, chip load, metal removal rate, horsepower, cutting efficiency, cutter wear (lack of) and chip removal methods.
The machine readable catalog is described. The machine version contains the same data as the published table, which includes a second file with the notes. The computerized data files are prepared at the Astronomical Data Center. Detected discrepancies and cluster identifications based on photometric estimators are included.
A description of the machine readable catalog, including detailed format and tape file characteristics, is given. The machine file is a computation of mean values for position and magnitude at a mean epoch of observation for each unique star in the Oxford, Paris, Bordeaux, Toulouse and Northern Hemisphere Algiers zone. The format was changed to effect more efficient data searching by position and additional duplicate entries were removed. The final catalog contains data for 997311 stars.
Teleoperation can be defined as the use of robotic devices having mobility, manipulative and some sensing capabilities, and remotely controlled by a human operator. The purpose of this paper is to discuss and exemplify technology issues related to the use of robots as man-extension or teleoperator systems in space. The main thrust of the paper is focused at research and development in the area of sensing- and computer-based automation from the viewpoint of man-machine interface devices and techniques. The objective of this R and D effort is to render space teleoperation efficient and safe through the use of devices and techniques which will permit integrated and task-level ('intelligent') two-way control communication between human operator and teleoperator machine in earth orbit.