1,412 research outputs found

    An autonomous rendezvous and docking system using cruise missile technologies

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    In November 1990 the Autonomous Rendezvous & Docking (AR&D) system was first demonstrated for members of NASA's Strategic Avionics Technology Working Group. This simulation utilized prototype hardware from the Cruise Missile and Advanced Centaur Avionics systems. The object was to show that all the accuracy, reliability and operational requirements established for a space craft to dock with Space Station Freedom could be met by the proposed system. The rapid prototyping capabilities of the Advanced Avionics Systems Development Laboratory were used to evaluate the proposed system in a real time, hardware in the loop simulation of the rendezvous and docking reference mission. The simulation permits manual, supervised automatic and fully autonomous operations to be evaluated. It is also being upgraded to be able to test an Autonomous Approach and Landing (AA&L) system. The AA&L and AR&D systems are very similar. Both use inertial guidance and control systems supplemented by GPS. Both use an Image Processing System (IPS), for target recognition and tracking. The IPS includes a general purpose multiprocessor computer and a selected suite of sensors that will provide the required relative position and orientation data. Graphic displays can also be generated by the computer, providing the astronaut / operator with real-time guidance and navigation data with enhanced video or sensor imagery

    Coyote Damage in the Southeastern United States

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    County agricultural agents in all 82 counties of Mississippi and Extension Wildlife Specialists in the other 10 southeastern states were asked to respond to a short questionnaire on coyote damage in their respective county or state. The questionnaire requested the respondents to: 1) indicate if the number of coyote reports have increased, decreased, or remained stable over the last 5 years, 2) indicate the number of reports they were aware of in the last year, 3) report the type of damage and the associated economic loss, 4) estimate the economic loss over the last 5 years, and 5) provide any additional comments

    A Survey of the Attitudes of Industrial Arts Teachers in the Tidewater Area of Virginia

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    The purpose of this study is to survey the attitudes of a small group of educators, industrial arts teachers in the Tidewater area of Virginia, toward competency-based education

    The Demand for and Consumption of Fluid Milk in Logan, Utah, 1949

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    Dairying is one of the most important agricultural enterprises in Utah. Income from the sale of dairy products by farmers within the state comprises about fifteen percent of the total farm income. Milk and its products are an essential part of the diet of practically all consumers. Its widespread use makes it a commodity that should receive special consideration and study. The continued growth of the industry depends upon how well it can meet the demands of the consumer in supplying quality dairy products at reasonable prices. The problems that need particular attention to bring about continued growth are efficient production on the farms, programs to increase the demand for and consumption of milk, sound price policies, seasonality of milk production, price spreads for milk of different grades and uses, and reduction in marketing

    A Study of Imperialism in Mexico, 1861-1867

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    One of the moving episodes in the life of this nation was the period of foreign intervention which threatened the very national existence of the Mexican nation from 1861 until 1867. The story, however, has its background a decade or so before the curtain rose on the drama of European imperialism. It began with a social revolution which is known in Mexican history as the Reforma. Speaking of this revolution, Parkes states that, The primary purpose of the Reform, like that of the French Revolution, was the destruction of feudalism. Its intellectual inspiration came from the philosophers of French liberalism, while its driving-force was the ambition of the mestizos. 1 This is significant to a study of the intervention because in reality the struggle which took place was as much an internal conflict as it was foreign

    Analysis of the Space Shuttle Orbiter skin panels under simulated hydrodynamic loads

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    The Space Shuttle orbiter skin panels were analyzed under pressure loads simulating hydrodynamic loads to determine their capability to sustain a potential ditching and to determine pressures that typically would produce failures. Two Dynamic Crash Analysis of Structures (DYCAST) finite element models were used. One model was used to represent skin panels (bays) in the center body, while a second model was used to analyze a fuselage bay in the wing region of the orbiter. From an assessment of the DYCAST nonlinear computer results, it is concluded that the probability is extremely high that most, if not all, of the lower skin panels would rupture under ditching conditions. Extremely high pressure loads which are produced under hydrodynamic planning conditions far exceed the very low predicted failure pressures for the skin panels. Consequently, a ditching of the orbiter is not considered to have a high probability of success and should not be considered a means of emergency landing unless no other option exists

    An overview of the crash dynamics failure behavior of metal and composite aircraft structures

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    An overview of failure behavior results is presented from some of the crash dynamics research conducted with concepts of aircraft elements and substructure not necessarily designed or optimized for energy absorption or crash loading considerations. Experimental and analytical data are presented that indicate some general trends in the failure behavior of a class of composite structures that includes fuselage panels, individual fuselage sections, fuselage frames, skeleton subfloors with stringers and floor beams without skin covering, and subfloors with skin added to the frame stringer structure. Although the behavior is complex, a strong similarity in the static/dynamic failure behavior among these structures is illustrated through photographs of the experimental results and through analytical data of generic composite structural models

    Letters. International Engineering Ethics Projects

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    Dear Sir: Ethical dilemmas facing engineers practicing in a culture other than their own is the topic of a current research project. The study will identify and collect information concerning ethical conflicts that can arise in all areas of engineering work—design, implementation, management, and interaction with local personnel and institutions. © 1980, American Chemical Society. All rights reserved
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