887 research outputs found

    An airborne meteorological data collection system using satellite relay (ASDAR)

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    The National Aeronautics and Space Administration (NASA) has developed an airborne data acquisition and communication system for the National Oceanic and Atmospheric Administration (NOAA). This system known as ASDAR, the Aircraft to Satellite Data Relay, consists of a microprocessor based controller, time clock, transmitter and antenna. Together they acquire meteorological and position information from existing aircraft systems on B-747 aircraft, convert and format these, and transmit them to the ground via the GOES meteorological satellite series. The development and application of the ASDAR system is described with emphasis on unique features. Performance to date is exceptional, providing horizon-to-horizon coverage of aircraft flights. The data collected is of high quality and is considered a valuable addition to the data base from which NOAA generates its weather forecasts

    Is Everything Neutral?

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    In his well-known analysis of the national debt, Robert Barro introduced the notion of a "dynastic family." This notion has since become a standard research tool, particularly in the areas of public finance and macroeconomics. In this paper, we critique the assumptions upon which the dynastic mode1 is predicated, and argue that this framework is not a suitable abstraction in contexts where the objective is to analyze the effects of public policies. We reach this conclusion by formally considering a world in which each generation consists of a large number of distinct individuals, as opposed to one representative individual. We point out that family linkages form complex networks, in which each individual may belong to many dynastic groupings. The resulting proliferation of linkages between families gives rise to a host of neutrality results, including the irrelevance of all public redistributions, distortionary taxes, and prices. Since these results are not at all descriptive of the real world, we conclude that, in some fundamental sense, the world is not even approximately dynastic. These observations call into question all policy related results based on the dynastic framework, including the Ricardian equivalence hypo thesis.

    Conspicuous Consumption, Pure Profits, and the Luxury Tax

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    We examine a model of conspicuous consumption and explore the nature of competition in markets for conspicuous goods. We assume that, in addition to intrinsic utility, individuals seek status, and that perceptions of wealth affect status. Under identifiable conditions, the model generates Veblen effects: utility is positively related to the price of the good consumed. Equilibria are then characterized by the existence of "budget' brands (which are sold at a price equal to marginal cost), as well as 'luxury" brands (which are sold at a price above marginal cost, despite the fact that producers are perfectly competitive). Luxury brands are not intrinsically superior to budget brands but are purchased by consumers who seek to signal high levels of wealth. Within the context of this model, an appropriately designed luxury tax is a non-distortionary tax on pure profits.

    A real time spectrum to dose conversion system

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    A system has been developed which permits the determination of dose in real time or near real time directly from the pulse-height output of a radiation spectrometer. The technique involves the use of the resolution matrix of a spectrometer, the radiation energy-to-dose conversion function, and the geometrical factors, although the order of matrix operations is reversed. The new technique yields a result which is mathematically identical to the standard method while requiring no matrix manipulations or resolution matrix storage in the remote computer. It utilizes only a single function for each type dose required and each geometric factor involved

    Scatterer that leaves "footprints" but no "fingerprints"

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    We calculate the exact transmission coefficient of a quantum wire in the presence of a single point defect at the wire's cut-off frequencies. We show that while the conductance pattern (i.e., the scattering) is strongly affected by the presence of the defect, the pattern is totally independent of the defect's characteristics (i.e., the defect that caused the scattering cannot be identified from that pattern).Comment: 4 pages, 3 figure

    LTV beta-bremsstrahlung spectrometer for Gemini 12 Final report

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    Design and operation of combination bremsstrahlung spectrometer and data processor for radiation monitoring during Gemini 7 fligh

    Resonances in a two-dimensional electron waveguide with a single delta-function scatterer

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    We study the conductance properties of a straight two-dimensional electron waveguide with an s-like scatterer modeled by a single delta-function potential with a finite number of modes. Even such a simple system exhibits interesting resonance phenomena. These resonances are explained in terms of quasi-bound states both by using a direct solution of the Schroedinger equation and by studying the Green's function of the system. Using the Green's function we calculate the survival probability as well as the power absorption and show the influence of the quasi-bound states on these two quantities.Comment: 5 pages, 6 figures, to be published in Physical Review

    (De)marketing to Manage Consumer Quality Inferences

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    Savvy consumers attribute a product’s market performance to its intrinsic quality as well as the seller’s marketing push. The authors study how sellers should optimize their marketing decisions in response. They find that a seller can benefit from “demarketing” its product, meaning visibly toning down its marketing efforts. Demarketing lowers expected sales ex ante but improves product quality image ex post, as consumers attribute good sales to superior quality and lackluster sales to insufficient marketing. The authors derive conditions under which demarketing can be a recommendable business strategy. A series of experiments confirm these prediction

    MICROBIAL BASED CHLORINATED ETHENE DESTRUCTION

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    A mixed culture of Dehalococcoides species is provided that has an ability to catalyze the complete dechlorination of polychlorinated ethenes such as PCE, TCE, cDCE, 1,1-DCE and vinyl chloride as well as halogenated ethanes such as 1,2-DCA and EDB. The mixed culture demonstrates the ability to achieve dechlorination even in the presence of high source concentrations of chlorinated ethenes
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