106,082 research outputs found

    Method of resolving clock synchronization error and means therefor Patent

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    Development of method for synchronizing clocks at several ground stations based on signals received from spacecraft or satellite

    Improved elastomer for use with oxygen difluoride

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    Method improves resistance of CIS-1,4-poly(butadiene) elastomers to attack by oxygen difluoride at low temperatures by replacing silica reinforcement with less reactive substances. Improved elastomeric compound is utilized in bladders, diaphragms, valves, O-rings and seals

    Communications link for SDS 900 series computers

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    High speed, self-clocking single channel control and data link apparatus interfaces between two computers. This combined system reduces data errors

    Color identification testing device

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    Testing device, which determines ability of a technician to identify color-coded electric wires, is superior to standard color blindness tests. It tests speed of wire selection, detects partial color blindness, allows rapid testing, and may be administered by a color blind person

    Killing and replacing queen-laid eggs: low cost of worker policing in the honey bee

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    Worker honeybees, Apis mellifera, police each other’s reproduction by killing worker-laid eggs. Previous experiments demonstrated that worker policing is effective, killing most (∼98%) worker-laid eggs. However, many queen-laid eggs were also killed (∼50%) suggesting that effective policing may have high costs. In these previous experiments, eggs were transferred using forceps into test cells, mostly into unrelated discriminator colonies. We measured both the survival of unmanipulated queen-laid eggs and the proportion of removal errors that were rectified by the queen laying a new egg. Across 2 days of the 3-day egg stage, only 9.6% of the queen-laid eggs in drone cells and 4.1% in worker cells were removed in error. When queen-laid eggs were removed from cells, 85% from drone cells and 61% from worker cells were replaced within 3 days. Worker policing in the honeybee has a high benefit to policing workers because workers are more related to the queen’s sons (brothers, r = 0.25) than sister workers’ sons (0.15). This study shows that worker policing also has a low cost in terms of the killing of queen-laid eggs, as only a small proportion of queen-laid eggs are killed, most of which are rapidly replaced

    B747/JT9D flight loads and their effect on engine running clearances and performance deterioration; BCAC NAIL/P and WA JT9D engine diagnostics programs

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    Flight loads on the 747 propulsion system and resulting JT9D blade to outer airseal running clearances during representative acceptance flight and revenue flight sequences were measured. The resulting rub induced clearance changes, and engine performance changes were then analyzed to validate and refine the JT9D-7A short term performance deterioration model

    Mu-2 ranging

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    The Mu-II Dual-Channel Sequential Ranging System designed as a model for future Deep Space Network ranging equipment is described. A list of design objectives is followed by a theoretical explanation of the digital demodulation techniques first employed in this machine. Hardware and software implementation are discussed, together with the details relating to the construction of the device. Two appendixes are included relating to the programming and operation of this equipment to yield the maximum scientific data

    Digital video display system

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    System displays image data in real time on 120,000-element raster scan with 2, 4, or 8 shades of grey. Designed for displaying planetary range Doppler data, system can be used for X-Y plotting, displaying alphanumerics, and providing image animation

    A study of cloud motions on Mars, part B Final report

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    Photographic plates used to map cloud motions on Mar
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