4,434 research outputs found
Optical tracker having overlapping reticles on parallel axes Patent
Optical tracker with pair of FM reticles having patterns 90 deg out of phas
In-flight friction and wear mechanism
A unique mechanism developed for conducting friction and wear experiments in orbit is described. The device is capable of testing twelve material samples simultaneously. Parameters considered critical include: power, weight, volume, mounting, cleanliness, and thermal designs. The device performed flawlessly in orbit over an eighteen month period and demonstrated the usefulness of this design for future unmanned spacecraft or shuttle applications
Metal Oxide Silicon /MOS/ transistors protected from destructive damage by wire
Loop of flexible, small diameter, nickel wire protects metal oxide silicon /MOS/ transistors from a damaging electrostatic potential. The wire is attached to a music-wire spring, slipped over the MOS transistor case, and released so the spring tensions the wire loop around all the transistor leads, shorting them together. This allows handling without danger of damage
Focus drive mechanism for the IUE scientific instrument
A compact, lightweight mechanism was developed for in-orbit adjustment of the position of the secondary mirror (focusing) of the International Ultraviolet Explored telescope. This device is a linear drive with small (.0004 in.) and highly repeatable step increments. Extremely close tolerances are also held in tilt and decentering. The unique mechanization is described with attention to the design details that contribute to positional accuracy. Lubrication, materials, thermal considerations, sealing, detenting against launch loads, and other features peculiar to flight hardware are discussed. The methods employed for mounting the low expansion quartz mirror with minimum distortion are also given
Research notes: Significance of incompatibility reactions of Rhizobium japonicum strains with soybean host genotypes
Soybeans normally nodulate with Rhizobium japonicum and fix nitrogen in symbiotic association. However, several interactions, under genetic control, have been reported which result in ineffective nodulation or failure of the fixation process despite substantial nodule development. The recessive gene, rj1 , (Williams and Lynch, 1954) in homozygous mode, results in the exclusion from nodulation of a broad spectrum of Rhizobium jabonicum strains in soil culture
Using and Interpreting the Bayesian Optimization Algorithm to Improve Early Stage Design of Marine Structures.
Early stage naval structural design continues to advance as designers seek to improve the quality and speed of the design process. The early stages of design produce preliminary dimensions or scantlings which control the cost and structural performance of a vessel. Increased complexity in the evaluation of structural response has led to a need for efficient algorithms well suited to solving structural design specific optimization problems. As problem sizes increase, existing optimizers can become slow or inaccurate. The Bayesian Optimization Algorithm (BOA) is presented as one solution to efficiently solve problems in the structural design optimization process.
The Bayesian optimization algorithm is an Estimation of Distribution Algorithm (EDA) that uses a statistical sample of potential design solutions to create and train a Bayesian network (BN). The application of BNs is well suited for nearly decomposable problem composition which closely matches rules based structural design evaluation. This makes the BOA well suited to solve complex early stage structural optimization problems. Additionally, the learning processes used to create and train the BNs can be analyzed and interpreted to capture design knowledge. This return of knowledge to the designer helps to improve designer intuition and model synthesis in the face of more complex and intricate models. The BNs are thus analyzed to augment design problem understanding and explore trade-offs within the design space. The result matches a paradigm shift in early stage optimization of naval structures. Designers gain better understanding of critical design variables and their interactions as compared to the previous focus on the single most optimal solution. This leads to efficient simulations which rapidly explore design spaces, document critical design variable relationships and enable the designer to create better early stage design solutions.PhDNaval Architecture and Marine EngineeringUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/133317/1/tedevine_1.pd
The New Fuzziness: Richard Rorty on Education
The New Fuzziness: Richard Rorty and Education is an examination of the works of Richard Rorty, focusing on his impact on education. Richard Rorty is one of the most provocative and influential of contemporary thinkers writing in English. This unpublished manuscript is written by Dr. Philip E. Devine, Professor of Philosophy at Providence College
Research Notes: Genetic Studies of Soybean Host Cultivar Interactions with Rhizobium Strains
Several genetic factors have been identified which govern specific nodulation response in soybeans. The RJ2 genotype, carried by the cultivars \u27Hardee\u27 and \u27CNS,\u27 conditions an ineffective response in specific combination with Rhizobium japonicum strains of serogroups c1 and 122. The ineffective response is characterized as the development of either cortical proliferations on the roots or rudimentary nodules, rather than normal nodules
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