2,664 research outputs found

    New england- a research-reliant region

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    New england universities and nasa progra

    Theory and Evidence on Mergers and Acquisitions by Small and Medium Enterprises

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    The theory of mergers and acquisitions (M&As) has been developed almost exclusively from the study of large deals by large firms. In this paper we argue that the behaviour and success of M&As by small and medium sized enterprises (SMEs) may be significantly different. Accordingly, we revisit established M&A theories, and develop a theoretical framework, and several testable hypotheses, regarding the distinctive features of SME M&As. Our empirical results support our expectations and show that, compared to large firms, acquiring SMEs: rely more intensively on external growth via M&As; are more likely to be withdrawn, suggesting that SMEs are more flexible, and more able to avoid deals that turn sour; and, finally, SME M&As are more likely to be financed with equity rather than debt, indicating that the influential financial pecking order theory is of less relevance to SMEs.mergers, acquisitions, small and medium sized enterprises

    Photovoltaic power systems workshop

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    Discussions are presented on apparent deficiencies in NASA planning and technology development relating to a standard power module (25-35 kW) and to future photovoltaic power systems in general. Topics of discussion consider the following: (1) adequate studies on power systems; (2) whether a standard power system module should be developed from a standard spacecraft; (3) identification of proper approaches to cost reduction; (4) energy storage avoidance; (5) attitude control; (6) thermal effects of heat rejection on solar array configuration stability; (7) assembly of large power systems in space; and (8) factoring terrestrial photovoltaic work into space power systems for possible payoff

    Emergence of Kinetic Behavior in Streaming Ultracold Neutral Plasmas

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    We create streaming ultracold neutral plasmas by tailoring the photoionizing laser beam that creates the plasma. By varying the electron temperature, we control the relative velocity of the streaming populations, and, in conjunction with variation of the plasma density, this controls the ion collisionality of the colliding streams. Laser-induced fluorescence is used to map the spatially resolved density and velocity distribution function for the ions. We identify the lack of local thermal equilibrium and distinct populations of interpenetrating, counter-streaming ions as signatures of kinetic behavior. Experimental data is compared with results from a one-dimensional, two-fluid numerical simulation.Comment: 8 pages, 6 figure

    Ultracold Neutral Plasmas

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    Ultracold neutral plasmas, formed by photoionizing laser-cooled atoms near the ionization threshold, have electron temperatures in the 1-1000 kelvin range and ion temperatures from tens of millikelvin to a few kelvin. They represent a new frontier in the study of neutral plasmas, which traditionally deals with much hotter systems, but they also blur the boundaries of plasma, atomic, condensed matter, and low temperature physics. Modelling these plasmas challenges computational techniques and theories of non-equilibrium systems, so the field has attracted great interest from the theoretical and computational physics communities. By varying laser intensities and wavelengths it is possible to accurately set the initial plasma density and energy, and charged-particle-detection and optical diagnostics allow precise measurements for comparison with theoretical predictions. Recent experiments using optical probes demonstrated that ions in the plasma equilibrate in a strongly coupled fluid phase. Strongly coupled plasmas, in which the electrical interaction energy between charged particles exceeds the average kinetic energy, reverse the traditional energy hierarchy underlying basic plasma concepts such as Debye screening and hydrodynamics. Equilibration in this regime is of particular interest because it involves the establishment of spatial correlations between particles, and it connects to the physics of the interiors of gas-giant planets and inertial confinement fusion devices.Comment: 89 pages, 54 image

    On the influence of the European trade barrier on the CHinese pv industry:Is the solution to the solar-dispute "successful"?

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    AbstractIn July 2013 the European Union (EU) imposed restrictions on Chinese solar photovoltaic (PV) manufacturers, looking to exporting to the EU. In this paper, we consider the impact of this trade barrier, using a sample of 454 stock-listed PV producing firms. We find that the trade barrier erased US8,19millionoffthevalueoftheaverageEuropeanPVmanufacturersandUS 8,19 million off the value of the average European PV manufacturers and US 247.03 million off the value of the average Chinese PV manufacturers. We also find that while the trade barrier reduced the willingness of the industry to reorganise, it stimulates Chinese manufacturers to reorganise both their domestic and their international operations. The latter, we warn, is likely an attempt by Chinese manufacturers to ‘tariff jump’. We conclude, therefore, that the trade barrier was both inefficient, in that it both hurt the companies it aimed to protect, and ineffective, as those it sought to punish may have circumvented it

    Creating Non-Maxwellian Velocity Distributions in Ultracold Plasmas

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    We present techniques to perturb, measure and model the ion velocity distribution in an ultracold neutral plasma produced by photoionization of strontium atoms. By optical pumping with circularly polarized light we promote ions with certain velocities to a different spin ground state, and probe the resulting perturbed velocity distribution through laser-induced fluorescence spectroscopy. We discuss various approaches to extract the velocity distribution from our measured spectra, and assess their quality through comparisons with molecular dynamic simulationsComment: 13 pages, 8 figure

    Velocity Relaxation in a Strongly Coupled Plasma

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    Collisional relaxation of Coulomb systems is studied in the strongly coupled regime. We use an optical pump-probe approach to manipulate and monitor the dynamics of ions in an ultracold neutral plasma, which allows direct measurement of relaxation rates in a regime where common Landau-Spitzer theory breaks down. Numerical simulations confirm the experimental results and display non-Markovian dynamics at early times.Comment: 5 pages, 5 figure

    Controlling Condensate Collapse and Expansion with an Optical Feshbach Resonance

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    We demonstrate control of the collapse and expansion of an 88Sr Bose-Einstein condensate using an optical Feshbach resonance (OFR) near the 1S0-3P1 intercombination transition at 689 nm. Significant changes in dynamics are caused by modifications of scattering length by up to +- ?10a_bg, where the background scattering length of 88Sr is a_bg = -2a0 (1a0 = 0.053 nm). Changes in scattering length are monitored through changes in the size of the condensate after a time-of-flight measurement. Because the background scattering length is close to zero, blue detuning of the OFR laser with respect to a photoassociative resonance leads to increased interaction energy and a faster condensate expansion, whereas red detuning triggers a collapse of the condensate. The results are modeled with the time-dependent nonlinear Gross-Pitaevskii equation.Comment: 5 pages, 3 figure
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