64 research outputs found

    Work Measurement Decision Diagram Development and Application at NASA\u27s Kennedy Space Center

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    This paper presents a decision flow diagram developed at NASA\u27s Kennedy Space Center for the selection of the appropriate work measurement methodologies for Space Shuttle processing

    Gravitomagnetism and Relative Observer Clock Effects

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    The gravitomagnetic clock effect and the Sagnac effect for circularly rotating orbits in stationary axisymmetric spacetimes are studied from a relative observer point of view, clarifying their relationships and the roles played by special observer families. In particular Semer\'ak's recent characterization of extremely accelerated observers in terms of the two-clock clock effect is shown to be complemented by a similarly special property of the single-clock clock effect.Comment: 19 pages, LaTeX, IOP macros with package epsf and 1 eps figure, to appear in Classical and Quantum Gravity, slight revisio

    Spinor Field in Bianchi type-I Universe: regular solutions

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    Self-consistent solutions to the nonlinear spinor field equations in General Relativity has been studied for the case of Bianchi type-I (B-I) space-time. It has been shown that, for some special type of nonliearity the model provides regular solution, but this singularity-free solutions are attained at the cost of broken dominant energy condition in Hawking-Penrose theorem. It has also been shown that the introduction of Λ\Lambda-term in the Lagrangian generates oscillations of the B-I model, which is not the case in absence of Λ\Lambda term. Moreover, for the linear spinor field, the Λ\Lambda term provides oscillatory solutions, those are regular everywhere, without violating dominant energy condition. Key words: Nonlinear spinor field (NLSF), Bianch type -I model (B-I), Λ\Lambda term PACS 98.80.C CosmologyComment: RevTex, 21 page

    Super-long Anabiosis of Ancient Microorganisms in Ice and Terrestrial Models for Development of Methods to Search for Life on Mars, Europa and other Planetary Bodies

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    Successful missions to Mars, Europe and other bodies of the Solar system have created a prerequisite to search for extraterrestrial life. The first attempts of microbial life detection on the Martian surface by the Viking landed missions gave no biological results. Microbiological investigations of the Martian subsurface ground ice layers seem to be more promising. It is well substantiated to consider the Antarctic ice sheet and the Antarctic and Arctic permafrost as terrestrial analogues of Martian habitats. The results of our long-standing microbiological studies of the Antarctic ice would provide the basis for detection of viable microbial cells on Mars. Our microbiological investigations of the deepest and thus most ancient strata of the Antarctic ice sheet for the first time gave evidence for the natural phenomenon of long-term anabiosis (preservation of viability and vitality for millennia years). A combination of classical microbiological methods, epifluorescence microscopy, SEM, TEM, molecular diagnostics, radioisotope labeling and other techniques made it possible for us to obtain convincing proof of the presence of pro- and eukaryotes in the Antarctic ice sheet. In this communication, we will review and discuss some critical issues related to the detection of viable microorganisms in cold terrestrial environments with regard to future searches for microbial life and/or its biological signatures on extraterrestrial objects

    Interacting spinor and scalar fields in Bianchi type-I Universe filled with viscous fluid: exact and numerical solutions

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    We consider a self-consistent system of spinor and scalar fields within the framework of a Bianchi type I gravitational field filled with viscous fluid in presence of a Λ\Lambda term. Exact self-consistent solutions to the corresponding spinor, scalar and BI gravitational field equations are obtained in terms of τ\tau, where τ\tau is the volume scale of BI universe. System of equations for τ\tau and \ve, where \ve is the energy of the viscous fluid, is deduced. Some special cases allowing exact solutions are thoroughly studied.Comment: 18 pages, 6 figure

    Protestant women in the late Soviet era: gender, authority, and dissent

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    At the peak of the anti-religious campaigns under Nikita Khrushchev, communist propaganda depicted women believers as either naïve dupes, tricked by the clergy, or as depraved fanatics; the Protestant “sektantka” (female sectarian) was a particularly prominent folk-devil. In fact, as this article shows, women’s position within Protestant communities was far more complex than either of these mythical figures would have one believe. The authors explore four important, but contested, female roles: women as leaders of worship, particularly in remote congregations where female believers vastly outnumbered their male counterparts; women as unofficial prophetesses, primarily within Pentecostal groups; women as mothers, replenishing congregations through high birth rates and commitment to their children’s religious upbringing; and women as political actors in the defence of religious rights. Using a wide range of sources, which include reports written by state officials, articles in the church journal, letters from church members to their ecclesiastical leaders in Moscow, samizdat texts, and oral history accounts, the authors probe women’s relationship with authority, in terms of both the authority of the (male) ministry within the church, and the authority of the Soviet state

    Using Work Measurement Techniques for Space Shuttle Ground Processing

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    Time standards are usually developed for highly repetitive tasks of short duration. Therefore, most of the work measurement techniques available for producing standards are formulated for this level of activity. There is an increasing need for standards on tasks that are less repetitive and of longer duration. It is also necessary to continue to ensure that the development of the standards is cost effective. One way to assist in minimizing cost is to select the appropriate technique for the application by considering development and implementation costs, feasibility, and consistency of the techniques. This paper presents a study of work measurement techniques as applied to space shuttle processing at the Kennedy Space Center with respect to these factors

    Time Standards -- Good Enough for Government Work?

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    This paper discusses the issues to be considered in the evaluation of the quality of time standards, with emphasis on an application at NASA\u27s Kennedy Space Center
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