13,037 research outputs found
Space shuttle engineering and operations support. Isolation between the S-band quad antenna and the S-band payload antenna. Engineering systems analysis
The isolation between the upper S-band quad antenna and the S-band payload antenna on the shuttle orbiter is calculated using a combination of plane surface and curved surface theories along with worst case values. A minimum value of 60 db isolation is predicted based on recent antenna pattern data, antenna locations on the orbiter, curvature effects, dielectric covering effects and edge effects of the payload bay. The calculated value of 60 db is significantly greater than the baseline value of 40 db. Use of the new value will result in the design of smaller, lighter weight and less expensive filters for S-band transponder and the S-band payload interrogator
An analysis of point-to-point communication for application to the lunar flyer program
Determining optimum frequency for point-to-point communication in vicinity of line-of-sight horizon on lunar surfac
Development, Survival and Phenology of the Sweetclover Weevil Parasitoid, \u3ci\u3ePygostolus Falcatus\u3c/i\u3e (Hymenoptera: Braconidae)
Biennial sweetclovers were widely used for soil improvement and as for- ages in the first half of the 1900s. The introduction of the sweetclover weevil, Sitona cylindricollis, caused a drastic decline in sweetclover acreage. In North Dakota, yellow sweetclover, Melilotus officinalis, is still the legume of choice on organic farms. In an effort to control the weevil, the thelyotokous parasitoid Pygostolus falcatus was imported. Parasitoids were studied for temperature-dependent development, and adult longevity as influenced by temperature and availability of provisions. Development from egg to adult at 15, 20, 25 and 30°C was 58, 28, 22 and 21 d, respectively. No parasitoids were reared out at 10°C, although diapausing first instars were present. Longevity of adult parasitoids provided honey, water, sweetclover and sweet- clover weevils at 15, 20, 25 and 30°C was 29, 22, 12 and 6 d, respectively. Adults provided the following combinations of provisions at 25°C survived for: nothing-2 d; water-2 d; honey-4 d; honey and water - 6 d; honey, water and sweetclover - 11 d; honey, water, sweetclover and hosts - 12 d. Field cage releases and a degree-day model developed for the parasitoid demonstrated that poor synchrony between P. falcatus and the sweetclover weevil hinders its usefulness as a biological control agent
Standards and separatism: the discursive construction of gender in English soccer coach education
Affirmative action is a problematic, but common,
organizational approach to redressing gender discrimination
as it fails to address discourses underlying organizational
definitions and practices in highly masculinized sites like
English football. Unstructured interviews with 27 key
personnel and participants in coach education in the north
of England within a regional “division” of the organization
regulating English football (“The FA”) were conducted to
explore the gendered construction and enactment of football
and coaching, and the framing of women-only (separatist)
coaching courses. Critical discourse analysis identified the
deployment of discourses concerning the undermining of
standards and the privileging of women as strategies used
to neutralize the significance of gender and previous gender
discrimination, while re/producing the centrality of masculinity for key definitions and identities
Limitations on Ku-band communications due to multipath
The earth and orbiter body reflections involving the Tracking Data Relay Satellite (TDRS)/orbiter communications link are evaluated. Recommendations address operational conditions in order to avoid critical multipath impacts, modulation preferences during acquisition, and preferred scan limit implementation
Daily Life in McMinnville 100 Years Ago
The McMinnville 100 Years Ago project is a collaborative research project that has been initiated by Professor Huntsberger’s History of Mass Communication class. This particular project topic focuses on the daily life of Yamhill County in 1912. As a group we have chosen to divide our project into different subject areas: churches, businesses, schools, recreation, and clothing. In order to learn about the daily life of Yamhill County, we analyzed historical evidence from Yamhill County in 1912, such as newspapers, pictures, and journals. These documents were found with help from the Yamhill County Historical Museum and the McMinnville Public Library. With this evidence, we crafted together a thorough portrayal on the daily life of Yamhill County in 1912
Flexible blade antenna Patent
Flexible monopole antenna with broad bandwidth and low voltage standing wave rati
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