667 research outputs found
The Impact of Tourism on Curacao's Economy: A Scenario Approach
Curaçao is an autonomous countrywithin the Kingdom of the Netherlands. The governmentwants to support tourism development. However,various development strategies are possible. This articlepresents four scenarios of marketing and investmentstrategies that will affect the number of tourists fromThe Netherlands and North America (USA and Canada)in different ways. A multiplier model was used to calculatethe economic impacts of the four scenarios. Bydoing so, this article shows how the government’s decisionto support particular marketing and investmentstrategies may have certain outcomes for the number ofjobs in Curaçao’s tourism industry
Large-Scale Structures Behind the Milky Way from Near-IR Surveys
About 25% of the optical extragalactic sky is obscured by the dust and stars
of our Milky Way. Dynamically important structures might still lie hidden in
this zone. Various approaches are presently being employed to uncover the
galaxy distribution in the Zone of Avoidance (ZOA) but all suffer from
(different) limitations and selection effects.
We investigated the potential of using the DENIS NIR survey for studies of
galaxies behind the obscuration layer of our Milky Way and for mapping the
Galactic extinction. As a pilot study, we recovered DENIS I, J and K band
images of heavily obscured but optically still visible galaxies. We determined
the I, J and K band luminosity functions of galaxies on three DENIS strips that
cross the center of the nearby, low-latitude, rich cluster Abell 3627. The
extinction-corrected I-J and J-K colours of these cluster galaxies compare well
with that of an unobscured cluster. We searched for and identified galaxies at
latitudes where the Milky Way remains fully opaque (|b|
4-5mag) - in a systematic search as well as around positions of galaxies
detected with the blind HI survey of the ZOA currently conducted with the
Multibeam Receiver of the Parkes Radiotelescope.Comment: 12 pages, including 5 PS figures, LaTeX, uses crckapb.sty and
epsf.tex. Better resolved figures available upon request. To appear in
proceedings of the 3rd Euroconference (Meudon, France, June 1997) on ``The
Impact of Near IR Surveys'', Kluwer 199
Decomposition driven interface evolution for layers of binary mixtures: I. Model derivation and stratified base states
A dynamical model is proposed to describe the coupled decomposition and
profile evolution of a free surface film of a binary mixture. An example is a
thin film of a polymer blend on a solid substrate undergoing simultaneous phase
separation and dewetting. The model is based on model-H describing the coupled
transport of the mass of one component (convective Cahn-Hilliard equation) and
momentum (Navier-Stokes-Korteweg equations) supplemented by appropriate
boundary conditions at the solid substrate and the free surface.
General transport equations are derived using phenomenological
non-equilibrium thermodynamics for a general non-isothermal setting taking into
account Soret and Dufour effects and interfacial viscosity for the internal
diffuse interface between the two components. Focusing on an isothermal setting
the resulting model is compared to literature results and its base states
corresponding to homogeneous or vertically stratified flat layers are analysed.Comment: Submitted to Physics of Fluid
Quantized representation of some nonlinear integrable evolution equations on the soliton sector
The Hirota algorithm for solving several integrable nonlinear evolution
equations is suggestive of a simple quantized representation of these equations
and their soliton solutions over a Fock space of bosons or of fermions. The
classical nonlinear wave equation becomes a nonlinear equation for an operator.
The solution of this equation is constructed through the operator analog of the
Hirota transformation. The classical N-solitons solution is the expectation
value of the solution operator in an N-particle state in the Fock space.Comment: 12 page
HI Bright Galaxies in the Southern Zone of Avoidance
A blind survey for HI bright galaxies in the southern Zone of Avoidance, (212
deg < l < 36 deg; |b| < 5 deg), has been made with the 21 cm multibeam receiver
on the Parkes 64 m radiotelescope. The survey, sensitive to normal spiral
galaxies to a distance of about 40 Mpc and more nearby dwarfs, detected 110
galaxies. Of these, 67 have no counterparts in the NASA/IPAC Extragalactic
Database. In general, the uncataloged galaxies lie behind thicker obscuration
than do the cataloged objects. All of the newly-discovered galaxies have HI
flux integrals more than an order of magnitude lower than the Circinus galaxy.
The survey recovers the Puppis cluster and foreground group (Kraan-Korteweg &
Huchtmeier 1992), and the Local Void remains empty. The HI mass function
derived for the sample is satisfactorily fit by a Schechter function with
parameters alpha = 1.51 +- 0.12, Phi* = 0.006 +- 0.003, and log M* = 9.7 +-
0.10.Comment: To appear in The Astronomical Journa
Exact Kink Solitons in the Presence of Diffusion, Dispersion, and Polynomial Nonlinearity
We describe exact kink soliton solutions to nonlinear partial differential
equations in the generic form u_{t} + P(u) u_{x} + \nu u_{xx} + \delta u_{xxx}
= A(u), with polynomial functions P(u) and A(u) of u=u(x,t), whose generality
allows the identification with a number of relevant equations in physics. We
emphasize the study of chirality of the solutions, and its relation with
diffusion, dispersion, and nonlinear effects, as well as its dependence on the
parity of the polynomials and with respect to the discrete
symmetry . We analyze two types of kink soliton solutions, which are
also solutions to 1+1 dimensional phi^{4} and phi^{6} field theories.Comment: 11 pages, Late
HI observations of nearby galaxies I. The first list of the Karachentsev catalog
We present HI observations of the galaxies in the first list of the
Karachentsev catalog of previously unknown nearby dwarf galaxies (Karachentseva
& Karachentsev 1998). This survey covers all known nearby galaxy groups within
the Local Volume (i.e. within 10 Mpc) and their environment, that is about 25%
of the total sky. A total of 257 galaxies have been observed with a detection
rate of 60%. We searched a frequency band corresponding to heliocentric radial
velocities from -470 km/s to about +4000 km/s. Non-detections are either due to
limited coverage in radial velocity, confusion with Local HI (mainly in the
velocity range -140 km/s to +20 km/s, or lack of sensitivity for very weak
emission. 25% of the detected galaxies are located within the Local Volume.
Those galaxies are dwarf galaxies judged by their optical linear diameter (1.4
+/- 0.2 kpc on the average), their mean total HI mass (4.6 E7 solar masses),
and their observed linewidths (39 km/s).Comment: 22 pages, 9 ps figures, A&AS, in pres
Chiral Solitons in Generalized Korteweg-de Vries Equations
Generalizations of the Korteweg-de Vries equation are considered, and some
explicit solutions are presented. There are situations where solutions engender
the interesting property of being chiral, that is, of having velocity
determined in terms of the parameters that define the generalized equation,
with a definite sign.Comment: 9 pages, latex, no figures. References added, typos correcte
Mining the Local Volume
After recent systematic optical, IR, and HI surveys, the total number of
known galaxies within 10 Mpc has increased from 179 to 550. About half this
Local Volume (LV) sample is now been imaged with HST, yielding the galaxy
distances with an accuracy of about 8%. For the majority of the LV galaxies we
currently have H-alpha fluxes that allow us to reconstruct the star formation
history of our neighbourhood.
For the late-type LV galaxies their HI masses and angular momentum follow the
linear relation in the range of 4 orders, which is expected for rotating
gaseous disks being near the gravitational instability threshold.
The data obtained on the LV galaxies imply important cosmological parameters,
in particular, the mean local matter density and HI mass density, as well as
SFR density.
Surprisingly, the local Hubble flow around the LV groups is very quiet, with
1D rms deviations of 25 km/s,which is a signature of the Universe
vacuum-dominated on small scales. The cold infall pattern around nearby groups
provides us with a new method to determine the total mass of the groups
independent from virial mass estimates.Comment: 10 pages, 6 figures, proceedings Symposium "Galaxies in the Local
Volume", Sydney, 8 - 13 July 2007, B. Koribalski and H. Jerjen, ed
Free Energy Minimizers for a Two--Species Model with Segregation and Liquid-Vapor Transition
We study the coexistence of phases in a two--species model whose free energy
is given by the scaling limit of a system with long range interactions (Kac
potentials) which are attractive between particles of the same species and
repulsive between different species.Comment: 32 pages, 1 fig, plain tex, typeset twic
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