15,816 research outputs found
An econometric analysis of SARS and Avian flu on international tourist arrivals to Asia
This paper compares the impacts of SARS and human deaths arising from Avian Flu on international tourist arrivals to Asia. The effects of SARS and human deaths from Avian Flu will be compared directly according to human deaths. The nature of the short run and long run relationship is examined empirically by estimating a static line fixed effect model and a difference transformation dynamic model, respectively. Empirical results from the static fixed effect and difference transformation dynamic models are consistent, and indicate that both the short run and long run SARS effect have a more significant impact on international tourist arrivals than does Avian Flu. In addition, the effects of deaths arising from both SARS and Avian Flu suggest that SARS is more important to international tourist arrivals than is Avian Flu. Thus, while Avian Flu is here to stay, its effect is currently not as significant as that of SARS.Avian flu;international tourism;SARS;dynamic panel data model;static fixed effects model
Estimating the impact of whaling on global whale watching
After the commercial whaling moratorium was enacted in 1986, whale watching became one of the fastest growing tourism industries worldwide. As whaling was regarded as an activity incompatible with whale watching, the possible resumption of commercial whaling caused an urgent need to investigate the potential negative effects of whaling on the whale-watching industry. We examine the potential impacts of whaling on the global whale-watching tourism industry using unbalanced panel data model. The empirical results indicate that the resumption of commercial whaling has the potential for a negative effect on the global whale-watching industry, especially for nations that are engaged in whaling.delay-difference equation model;global whale watching;whaling
S-OGSA as a Reference Architecture for OntoGrid and for the Semantic Grid
The Grid aims to support secure, flexible and coordinated resource sharing through providing a middleware platform for advanced distributing computing. Consequently, the Grid’s infrastructural machinery aims to allow collections of any kind of resources—computing, storage, data sets, digital libraries, scientific instruments, people, etc—to easily form Virtual Organisations (VOs) that cross organisational boundaries in order to work together to solve a problem. A Grid depends on understanding the available resources, their capabilities, how to assemble them and how to best exploit them. Thus Grid middleware and the Grid applications they support thrive on the metadata that describes resources in all their forms, the VOs, the policies that drive then and so on, together with the knowledge to apply that metadata intelligently
A hierarchy of avalanche models on arbitrary topography
We use the non-Cartesian, topography-based equations of mass and momentum balance for gravity driven frictional flows of Luca etal. (Math. Mod. Meth. Appl. Sci. 19, 127-171 (2009)) to motivate a study on various approximations of avalanche models for single-phase granular materials. By introducing scaling approximations we develop a hierarchy of model equations which differ by degrees in shallowness, basal curvature, peculiarity of constitutive formulation (non-Newtonian viscous fluids, Savage-Hutter model) and velocity profile parametrization. An interesting result is that differences due to the constitutive behaviour are largely eliminated by scaling approximations. Emphasis is on avalanche flows; however, most equations presented here can be used in the dynamics of other thin films on arbitrary surface
Modeling Shallow Over-Saturated Mixtures on Arbitrary Rigid Topography
In this paper a system of depth-integrated equations for over-saturated debris flows on three-dimensional topography is derived. The lower layer is a saturated mixture of density preserving solid and fluid constituents, where the pore fluid is in excess, so that an upper fluid layer develops above the mixture layer. At the layer interface fluid mass exchange may exist and for this a parameterization is needed. The emphasis is on the description of the influence on the flow by the curvature of the basal surface, and not on proposing rheological models of the avalanching mass. To this end, a coordinate system fitted to the topography has been used to properly account for the geometry of the basal surface. Thus, the modeling equations have been written in terms of these coordinates, and then simplified by using (1) the depth-averaging technique and (2) ordering approximations in terms of an aspect ratio ϵ which accounts for the scale of the flowing mass. The ensuing equations have been complemented by closure relations, but any other such relations can be postulated. For a shallow two-layer debris with clean water in the upper layer, flowing on a slightly curved surface, the equilibrium free surface is shown to be horizonta
The first operation and results of the Chung-Li VHF radar
The Chung-Li Very High Frequency (VHF) radar is used in the dual-mode operations, applying Doppler beam-swinging as well as the spaced-antenna-drift method. The design of the VHF radar is examined. Results of performance tests are discussed
Ritual Perayaan Imlek Etnis Tionghoa Di Kota Toli-toli
Penduduk Tiongkok telah lama menyebar ke berbagai belahan dunia, dengan membawa berbagai macam kebudayaan serta tradisi, tidak terkecuali di Indonesia. Etnis tionghoa menyebar dengan merata di seluruh Indonesia dengan membawa kebudayaan asal mereka. Hari raya Imlek adalah salah satu contohnya, setiap daerah di Indonesia mempunyai perayaan Imlek mereka sendiri oleh karena itu penulis tertarik untuk meneliti perayaan etnis Tionghoa di kota Toli-toli. Penelitian ini meliputi apa perbedaan Imlek etnis Tionghoa Toli-toli pada masa orde baru dan mengapa terjadi perbedaan itu. Setelah dilakukan penelitian ditemukan bahwa etnis Tionghoa hanya merayakan chuxi, Imlek, hari kedua, hari kesembilan, dan Cap Go Meh. Perayaan Cap Go Meh di kota Toli-toli cenderung sepi dan tidak ada yang spesial. Serta ditemukan faktor yang membuat Imlek di kota Toli-toli saat orde baru dan sekarang berbeda yaitu karena faktor politik dan ekonomi
Fluctuations of the Retarded Van der Waals Force
The retarded Van der Waals force between a polarizable particle and a
perfectly conducting plate is re-examined. The expression for this force given
by Casimir and Polder represents a mean force, but there are large fluctuations
around this mean value on short time scales which are of the same order of
magnitude as the mean force itself. However, these fluctuations occur on time
scales which are typically of the order of the light travel time between the
atom and the plate. As a consequence, they will not be observed in an
experiment which measures the force averaged over a much longer time. In the
large time limit, the magnitude of the mean squared velocity of a test particle
due to this fluctuating Van der Waals force approaches a constant, and is
similar to a Brownian motion of a test particle in an thermal bath with an
effective temperature. However the fluctuations are not isotropic in this case,
and the shift in the mean square velocity components can even be negative. We
interpret this negative shift to correspond to a reduction in the velocity
spread of a wavepacket. The force fluctuations discussed in this paper are
special case of the more general problem of stress tensor fluctuations. These
are of interest in a variety of areas fo physics, including gravity theory.
Thus the effects of Van der Waals force fluctuations serve as a useful model
for better understanding quantum effects in gravity theory.Comment: 14 pages, no figure
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