19,855 research outputs found

    Scientific publications and presentations relating to planetary quarantine. Volume 5: The 1975 supplement

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    Documents pertaining to planetary quarantine are listed. An author index is given along with a listing of books and journals containing related material

    Conformational Control of Exciton-Polariton Physics in Metal - Poly(9,9-dioctylfluorene) - Metal Cavities

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    Control is exerted over the exciton-polariton physics in metal - Poly(9,9-dioctyl fluorene) - metal microcavities via conformational changes to the polymer backbone. Using thin-film samples containing increasing fractions of β\beta-phase chain segments, a systematic study is reported for the mode characteristics and resulting light emission properties of cavities containing two distinct exciton sub-populations within the same semiconductor. Ultrastrong coupling for disordered glassy-phase excitons is observed from angle-resolved reflectivity measurements, with Rabi splitting energies in excess of 1.05 eV (more than 30% of the exciton transition energy) for both TE- and TM-polarized light. A splitting of the lower polariton branch is then induced via introduction of β\beta-phase excitons and increases with their growing fraction. In all cases, the photoluminescence emanates from the lowermost polariton branch, allowing conformational control to be exerted over the emission energy and its angular variation. Dispersion-free cavities with highly saturated blue-violet emission are thus enabled. Experimental results are discussed in terms of the full Hopfield Hamiltonian generalized to the case of two exciton oscillators. The importance of taking account of the molecular characteristics of the semiconductor for an accurate description of its strong coupling behaviour is directly considered, in specific relation to the role of the vibronic structure

    Scientific publications and presentations relating to planetary quarantine. Volume 5 - The 1970 supplement

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    Bibliography of scientific publications and presentations relating to planetary quarantine for year 1970 - Vol.

    Portable digital pressure indicator for calibrating magnetic tape recorders

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    The design of a portable Digital Pressure Indicator (DPI) to be used for calibrating the pressure systems on Langley's magnetic tape recorders is described. High-speed magnetic tape recorders require pressure (0 to 20 psig) for providing an air cushion across the tape guides and a slight vacuum (30 inch H2O) for maintaining the proper number of tape loops in the advance and feed chamber. The DPI is a hand-held device that can be quickly coupled to a magnetic tape recorder and includes a two-position switch for selecting either measured pressure or vacuum, to be displayed digitally in engineering units (psig or inches H2O). The DPI is currently in use in Langley's Analysis and Computation Division

    Publications of the planetary biology program for 1976: A special bibliography

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    An annual listing of current publications resulting from research pursued under the auspices of NASA's Planetary Biology Program is presented. To stimulate the exchange of information and ideas among scientists working in the different areas of the program. To facilitate the exchange process. The author of each publication who is presently participating in the program is identified by asterisk. Current addresses for all principal investigators are given in the appendix

    Scientific publications and presentations relating to planetary quarantine. Volume 5: The 1971 supplement

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    A bibliographic compilation, with approximately 200 listings, on planetary quarantine is presented. Also given are scientific publications, and presentations along with an author index

    Scientific publications and presentations relating to planetary quarantine. Volume 5: The 1972 supplement

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    The sixth annual supplement to the bibliography on planetary quarantine contains 191 references, an author index and a permuted title index

    Study program of local angle-of-attack effects on vehicle dynamic response Final report

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    Effects of flexible body aerodynamics on launch vehicle

    Mumford dendrograms and discrete p-adic symmetries

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    In this article, we present an effective encoding of dendrograms by embedding them into the Bruhat-Tits trees associated to pp-adic number fields. As an application, we show how strings over a finite alphabet can be encoded in cyclotomic extensions of Qp\mathbb{Q}_p and discuss pp-adic DNA encoding. The application leads to fast pp-adic agglomerative hierarchic algorithms similar to the ones recently used e.g. by A. Khrennikov and others. From the viewpoint of pp-adic geometry, to encode a dendrogram XX in a pp-adic field KK means to fix a set SS of KK-rational punctures on the pp-adic projective line P1\mathbb{P}^1. To P1∖S\mathbb{P}^1\setminus S is associated in a natural way a subtree inside the Bruhat-Tits tree which recovers XX, a method first used by F. Kato in 1999 in the classification of discrete subgroups of PGL2(K)\textrm{PGL}_2(K). Next, we show how the pp-adic moduli space M0,n\mathfrak{M}_{0,n} of P1\mathbb{P}^1 with nn punctures can be applied to the study of time series of dendrograms and those symmetries arising from hyperbolic actions on P1\mathbb{P}^1. In this way, we can associate to certain classes of dynamical systems a Mumford curve, i.e. a pp-adic algebraic curve with totally degenerate reduction modulo pp. Finally, we indicate some of our results in the study of general discrete actions on P1\mathbb{P}^1, and their relation to pp-adic Hurwitz spaces.Comment: 14 pages, 6 figure
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