39,028 research outputs found
Evaluating methodological issues in the tourism literature: UK outgoing tourism and trade links
This paper evaluates the importance of trade in goods when modelling demand for tourism. It is argued that the limited literature testing causality between trade in goods and tourism does not consider the appropriate variables. This study utilises bilateral data for 16 UK tourist destinations in order to test Granger causality between trade in goods and tourism expenditure. UK imports, exports and total trade are tested separately, whilst controlling for real GDP and real bilateral exchange rates. The novelty of this paper is the variable specification, as well as testing the causal relationship for the case of UK outgoing tourists. Our findings suggest a causal relationship between the tourism expenditure of UK residents and trade in goods. These results support the inclusion of a trade in goods variable when estimating tourism demand, as well as adopting appropriate methodologies to account for this causal relationship. Furthermore, there is strong evidence that the trade-tourism link is important for both the UK and host countries
Theoretical pressure distributions over arbitrarily shaped periodic waves in subsonic compressible flow and comparison with experiment
Theoretical solution for pressure distribution over arbitrarily shaped periodic waves using Fourier serie
Very low sound velocities in iron-rich (Mg,Fe)O: Implications for the core-mantle boundary region
The sound velocities of (Mg_(.16)Fe_(.84))O have been measured to 121 GPa at ambient temperature using nuclear resonant inelastic x-ray scattering. The effect of electronic environment of the iron sites on the sound velocities were tracked in situ using synchrotron Mössbauer spectroscopy. We found the sound velocities of (Mg_(.16)Fe_(.84))O to be much lower than those in other presumed mantle phases at similar conditions, most notably at very high pressures. Conservative estimates of the effect of temperature and dilution on aggregate sound velocities show that only a small amount of iron-rich (Mg,Fe)O can greatly reduce the average sound velocity of an assemblage. We propose that iron-rich (Mg,Fe)O be a source of ultra-low velocity zones. Other properties of this phase, such as enhanced density and dynamic stability, strongly support the presence of iron-rich (Mg,Fe)O in localized patches above the core-mantle boundary
Dispersion and transitions of dipolar plasmon modes in graded plasmonic waveguides
Coupled plasmon modes are studied in graded plasmonic waveguides, which are
periodic chains of metallic nanoparticles embedded in a host with gradually
varying refractive indices. We identify three types of localized modes called
"light", "heavy", and "light-heavy" plasmonic gradons outside the passband,
according to various degrees of localization. We also demonstrate new
transitions among extended and localized modes when the interparticle
separation is smaller than a critical , whereas the three types of
localized modes occur for , with no extended modes. The transitions can
be explained with phase diagrams constructed for the lossless metallic systems.Comment: Preliminary results have been presented at ETOPIM 7. Submitted to
Appl. Phys. Let
Carrier extraction circuit
Feedback loop extracts demodulated reference signals from IF input and feeds signal back to demodulator. Since reference signal is extracted directly from carrier, no separate reference need be transmitted. Circuit obtains coherent carrier from balanced or unbalanced four-phase signal of varying characteristics
Temperature dependence in random matrix models with pairing condensates
We address a number of issues raised by a manuscript of Klein, Toublan, and
Verbaarschot (hep-ph/0405180) in which the authors introduce a random matrix
model for QCD with two colors, two flavors, and fermions in the fundamental
representation. Their inclusion of temperature terms differs from the approach
adopted in previous work on this problem (Phys. Rev. D 64, 074016 (2001).) We
demonstrate that the two approaches are related by a transformation that leaves
the thermodynamic potential invariant and which therefore has no effect on
physical observables.Comment: 8 pages, revtex4. v2: typos corrected in reference
Strategy for designing broadband epsilon-near-zero metamaterial with loss compensation by gain media
A strategy is proposed to design the broadband gain-doped epsilon-near-zero
(GENZ) metamaterial. Based on the Milton representation of effective
permittivity, the strategy starts in a dimensionless spectral space, where the
effective permittivity of GENZ metamaterial is simply determined by a pole-zero
structure corresponding to the operating frequency range. The physical
structure of GENZ metamaterial is retrieved from the pole-zero structure via a
tractable inverse problem. The strategy is of great advantage in practical
applications and also theoretically reveals the cancellation mechanism
dominating the broadband near-zero permittivity phenomenon in the spectral
space
Turbulent Skin Friction at High Reynolds Numbers and Low Supersonic Velocities
Turbulent skin friction at high Reynolds number and low supersonic speed
Optical alignment system Patent
Electro-optical/computer system for aligning large structural members and maintaining correct positio
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