19,590 research outputs found

    Passive optical wind and turbulence detection system Patent

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    Passive optical wind and turbulence remote detection syste

    Has Europe Been Catching Up? An Industry Level Analysis of Venture Capital Success over 1985 - 2009

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    After nearly two decades of U.S. leadership in the 1980s and 1990s, are Europe's venture capital markets in the 2000s finally catching up regarding the provision of financing and successful exits, or is the performance gap as wide as ever? Are we amidst overall dismal performance of the venture capital experience without any encouraging news? We attempt to answer these questions by tracking down over 40,000 venture capital--backed firms of six industries in 13 European countries and the U.S., and determine which type of exit - if any - each particular firm's investors have chosen between 1985 and 2009. Our empirical findings suggest that: (i) in terms of the number of venture capital-backed firms successfully going public, European venture capitalists have closed the gap with respect to the U.S., albeit as a result of a worse initial public offering performance overall; (ii) Europe continues to lag behind the U.S. by means of mergers and acquisitions, and in successful exits of seed/start-up and early stage firms, (iii) average investment and R&D are important determinants of venture capital success, but only have a positive impact after 2000; and (iv) idiosyncratic differences across industries seem to be more relevant than country-specific characteristics in explaining differences in performance.Venture capital, private equity, success rates, performance, IPOs.

    Nonsteady flow-direction measurement

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    Nonsteady flow probe uses miniature pressure transducers mounted within probe support very close to tube inlets. Response speed depends on internal volume between tube inlet and pressure transducer location

    Study of hot wire techniques in low density flows with high turbulence levels

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    Prediction of heat, mass, species, and momentum fluxes in a space vehicle and aerodynamic noise production by supersonic jet and rocket exhausts requires a predictability of the associated turbulence fields. The hot wire is a technique that will allow an experimental determination of turbulent properties

    Potentiality and Contradiction in Quantum Mechanics

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    Following J.-Y.B\'eziau in his pioneer work on non-standard interpretations of the traditional square of opposition, we have applied the abstract structure of the square to study the relation of opposition between states in superposition in orthodox quantum mechanics in \cite{are14}. Our conclusion was that such states are \ita{contraries} (\ita{i.e.} both can be false, but both cannot be true), contradicting previous analyzes that have led to different results, such as those claiming that those states represent \ita{contradictory} properties (\ita{i. e.} they must have opposite truth values). In this chapter we bring the issue once again into the center of the stage, but now discussing the metaphysical presuppositions which underlie each kind of analysis and which lead to each kind of result, discussing in particular the idea that superpositions represent potential contradictions. We shall argue that the analysis according to which states in superposition are contrary rather than contradictory is still more plausible

    Physical Transport and Chemical Behavior of Dispersed Oil

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    During response operations, scientific information is provided to decision makers, such as the Federal On-Scene Coordinator (FOSC), state and federal trustees, and the public. The decision to use chemical dispersants during a response is made among all these parties, and during the Deepwater Horizon (DWH) oil spill the dispersant discussion included both surface and subsurface application of chemical dispersants. This paper is intended to provide perspective on research needs considered pre- and post-DWH oil spill related to response modeling and data collection needs for decision support of dispersant application and its potential effects. Given time constraints for implementing models and sampling strategies for response, requirements for data and types of questions to be addressed may be significantly different than requirements for research or damage assessment activities. At the time of this writing, just over a year after the successful response operations to cap the well, many studies are still in progress, and data are still being collected and evaluated to assess dispersant effectiveness and possible impacts. More information and research results will become available over the next months to years. Thus these research needs, as summarized for this workshop, should be evaluated again at a later time

    Applications of remote sensing to stream discharge predictions

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    A feasibility study has been initiated on the use of remote earth observations for augmenting stream discharge prediction for the design and/or operation of major reservoir systems, pumping systems and irrigation systems. The near-term objectives are the interpolation of sparsely instrumented precipitation surveillance networks and the direct measurement of water loss by evaporation. The first steps of the study covered a survey of existing reservoir systems, stream discharge prediction methods, gage networks and the development of a self-adaptive variation of the Kentucky Watershed model, SNOPSET, that includes snowmelt. As a result of these studies, a special three channel scanner is being built for a small aircraft, which should provide snow, temperature and water vapor maps for the spatial and temporal interpolation of stream gages

    Optical crossed-beam investigation of local sound generation in jets

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    Cross correlation of optical signals from two light beam sound detectors for jet noise source localizatio
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