20,746 research outputs found

    Novel horn antenna reduces side lobes, improves radiation pattern

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    A horn antenna, combining two propagation modes at selected power ratios, reduces side lobes, and improves the radiation characteristics. Noise and unwanted signals are considerably suppressed

    Angelology in situ : recovering higher-order beings as emblems of transcendence, immanence and imagination

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    The aim of this study is twofold: to identify the theological purpose underlying the depiction of angels at certain key points in the history of their use, and to explore how far that deeper theological rationale can be re-appropriated for our own day. This study first traces the progression of the angelic motif in the Hebrew Scriptures. By examining numerous pericopes in the Pentateuch, major prophets and Daniel, I demonstrate that the metamorphosis of higher-order beings like the angel of the Lord, cherubim and seraphim, is directly related to the writers’ desire to enhance God’s transcendence. Next, I evaluate pseudo-Denys’ hierarchical angelology, which prominent theologians like Luther and Calvin condemned as little more than a Neoplatonic scheme for accessing God through angels. I propose that not only has pseudo-Denys’ Neoplatonism been overstated, but that his angelology is particularly noteworthy for the way it accentuates Christ’s eucharistic immanence to the Church. Then I maintain that because assessments of Aquinas’ angelology are often based upon the Summa Theologiae, his views are wrongly portrayed as overtly philosophical, rather than biblical and exegetical. In his lesser-known biblical commentaries, however, Aquinas pushes the semantic range of the word ‘angel’ to include aspects of the physical world, which unveils an imaginative, Christocentric, and scriptural dimension of his angelology that is rarely acknowledged. The conclusion considers how contemporary figures and movements relate to these three angelologies. Barth emphasises the transcendent God but unlike Hebrew Scripture, weakens connections between God and angels. New Ageism affirms the immanent angel but unlike pseudo-Denys, does so at the expense of Christology and ecclesiology. Contemporary ecological discourse generally lacks Aquinas’ appreciation for an imaginative, supernatural approach to the world. Finally, I ground the angels’ relationship to transcendence, immanence and imagination in an experiential, eucharistic context

    Cassegrainian antenna subflector flange for suppressing ground noise Patent

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    Cassegrain antenna subreflector flange for suppressing ground noise and increasing antenna transmitting efficienc

    Choice of antenna geometry for microwave power transmission from solar power satellites

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    A comparison is made between square and circular transmitting antennas for solar power satellite microwave power transmission. It is seen that the exclusion zone around the rectenna needed to protect populations from microwaves is smaller for a circular antenna operating at 2.45 GHz than it is for a square antenna at that frequency. If the frequency is increased, the exclusion zone size remains the same for a square antenna, but becomes even smaller for a circular antenna. Peak beam intensity is the same for both antennas if the frequency and antenna area are equal. The circular antenna puts a somewhat greater amount of power in the main lobe and somewhat less in the side lobes. Since rain attenuation and atmospheric heating remain problems above 10 GHz, it is recommended that future solar power satellite work concentrate on circular transmitting antennas at frequencies of roughly 10 GHz

    Great Bay Estuary Tidal Tributary Monitoring Program: Quality Assurance Project Plan, 2018

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    Redesigning Nursing Education: Lessons Learned from the Oregon Experience

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    Offers evaluation findings, lessons learned, and guidance from a coalition of community colleges and university nursing programs that offer a standard competency-based curriculum to enable students to make a seamless transition and raise skill levels

    Predatory Insects and Spiders From Suburban Lawns in Lexington, Kentucky

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    Predatory arthropods were caught in pitfall traps in suburban lawns in Lexington, Kentucky. The relative abundance of species of Lycosidae, Carabidae, and Staphylinidae was compared in Kentucky bluegrass and tall fescue turf. Nine species of Lycosidae were collected from both the bluegrass and tall fescue lawns. More species or phena of Carabidae were collected from bluegrass than from tall fescue turf. More than 40 species or phena of staphylinids were collected from each grass habitat. Both Kentucky bluegrass and tall fescue are inhabited by an abundant and diverse array of predatory arthropods

    Quantitative determination of stratospheric aerosol characteristics

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    There are no author-identified significant results in this report

    Saturation of interband absorption in graphene

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    The transient response of an intrinsic graphene, which is caused by the ultrafast interband transitions, is studied theoretically for the range of pumping correspondent to the saturated absorption regime. Spectral and temporal dependencies of the photoexcited concentration as well as the transmission and relitive absotption coefficients are considered for mid-IR and visible (or near-IR) spectral regions at different durations of pulse and broadening energies. The characteristic intencities of saturation are calculated and the results are compared with the experimental data measured for the near-IR lasers with a saturable absorber. The negative absorption of a probe radiation during cascade emission of optical phonons is obtained.Comment: 7 pages, 7 figure
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