835 research outputs found
Assessing the Dynamic Economic Impact of Tourism in a Developing Region in South Africa
According to the National Development Plan (NDP), the three main developmental problems South Africa is facing include: high levels of unemployment, poverty and inequality. Tourism, as an economic sector, has been cited as a possible solution to create much-needed employment and income which could lead to reduced poverty and improved inequality. Tourism could be used in developing regions as a driver of economic growth. The objective of this study is to determine the dynamic impact of the tourism sector on economic growth in a developing region in South Africa, namely the Vaal-Triangle region. The research methodology followed a quantitative design, using a pooled panel approach including the two municipal areas of Metsimaholo and Emfuleni which comprises the Vaal region. Annual data from 2001 to 2017 were used to analyse the impact of growth in tourism on economic growth. Economic growth was set as the dependent variable and tourism measurements such as tourism spending and trips as the independent variables. Results from the analysis confirm the original hypothesis that tourism growth has a significant impact on economic growth. The sector therefore, has the potential to create employment opportunities and alleviate poverty in a developing region if promoted and supported to its full potential.  
Perturbative and non-perturbative aspects of the proper time renormalization group
The renormalization group flow equation obtained by means of a proper time
regulator is used to calculate the two loop beta function and anomalous
dimension eta of the field for the O(N) symmetric scalar theory. The standard
perturbative analysis of the flow equation does not yield the correct results
for both beta and eta. We also show that it is still possible to extract the
correct beta and eta from the flow equation in a particular limit of the
infrared scale. A modification of the derivation of the Exact Renormalization
Group flow, which involves a more general class of regulators, to recover the
proper time renormalization group flow is analyzed.Comment: 26 pages.Latex.Version accepted for publicatio
Management of fiscal and monetary policies interdependence in South African economy : A Bayesian VAR approach
Abstract: Purpose of the study: This study revisits the management and interaction aspects between fiscal and monetary policies in South Africa using a Bayesian vector autoregressive model (BVA). Design/methodology/approach: Monthly data on the inflation rate, interest rate, money supply, tax revenue, government spending and government debt for the period 2009 - 2019 were sourced from the South African Reserve Bank. Findings: The impulse response analysis shows that positive shocks to money supply prompt monetary authority to raise the economy's interest rate, which increases the bank rate. Inflation does not respond to shock to government spending and could drive inflation in the South African economy from the supply side rather than the demand side. Tax revenue and money supply shocks are significant sources of variation in inflation. These variables account for 7 and 18 percent variation in government spending. Recommendations/value: The study concludes that monetary authority must employ supply-side measures to manage the price level
A Focus on Subtle Signs and Motor Behavior to Unveil Awareness in Unresponsive Brain-Impaired Patients: The Importance of Being Clinical.
Brain-injured patients in a state of cognitive motor dissociation (CMD) exhibit a lack of command following using conventional neurobehavioral examination tools but a high level of awareness and language processing when assessed using advanced imaging and electrophysiology techniques. Because of their behavioral unresponsiveness, patients with CMD may seem clinically indistinguishable from those with a true disorder of consciousness that affects awareness on a substantial level (coma, vegetative state/unresponsive wakefulness state, or minimally conscious state minus). Yet, by expanding the range of motor testing across limb, facial, and ocular motricity, we may detect subtle, purposeful movements even in the subset of patients classified as vegetative state/unresponsive wakefulness state. We propose the term of clinical CMD to describe patients showing these slight but determined motor responses and exhibiting a characteristic akinetic motor behavior as opposed to a pyramidal motor system behavior. These patients may harbor hidden cognitive capabilities and significant potential for a good long-term outcome. Indeed, we envision CMD as ranging from complete (no motor response) to partial (subtle clinical motor response) forms, falling within a spectrum of progressively better motor output in patients with considerable cognitive capabilities. In addition to providing a decisional flowchart, we present this novel approach to classification as a graphical model that illustrates the range of clinical manifestations and recovery trajectories fundamentally differentiating true disorders of consciousness from the spectrum of CMD
Aspects of the FM Kondo Model: From Unbiased MC Simulations to Back-of-an-Envelope Explanations
Effective models are derived from the ferromagnetic Kondo lattice model with
classical corespins, which greatly reduce the numerical effort. Results for
these models are presented. They indicate that double exchange gives the
correct order of magnitude and the correct doping dependence of the Curie
temperature. Furthermore, we find that the jump in the particle density
previously interpreted as phase separation is rather explained by ferromagnetic
polarons.Comment: Proceedings of Wandlitz Days of Magnetism 200
Statistical Survey of Type III Radio Bursts at Long Wavelengths Observed by the Solar TErrestrial RElations Observatory (STEREO)/Waves Instruments: Radio Flux Density Variations with Frequency
We have performed a statistical study of Type III radio bursts observed
by Solar TErrestrial RElations Observatory (STEREO)/Waves between May 2007 and
February 2013. We have investigated the flux density between kHz and
MHz. Both high- and low-frequency cutoffs have been observed in of
events suggesting an important role of propagation. As already reported by
previous authors, we observed that the maximum flux density occurs at MHz on
both spacecraft. We have developed a simplified analytical model of the flux
density as a function of radial distance and compared it to the STEREO/Waves
data.Comment: published in Solar Physic
The Functional Renormalization Group and O(4) scaling
The critical behavior of the chiral quark-meson model is studied within the
Functional Renormalization Group (FRG). We derive the flow equation for the
scale dependent thermodynamic potential at finite temperature and density in
the presence of a symmetry-breaking external field. Within this scheme, the
critical scaling behavior of the order parameter, its transverse and
longitudinal susceptibilities as well as the correlation lengths near the
chiral phase transition are computed. We focus on the scaling properties of
these observables at non-vanishing external field when approaching the critical
point from the symmetric as well as from the broken phase. We confront our
numerical results with the Widom-Griffiths form of the magnetic equation of
state, obtained by a systematic epsilon-expansion of the scaling function. Our
results for the critical exponents are consistent with those recently computed
within Lattice Monte-Carlo studies of the O(4) spin system.Comment: 14 pages, 11 figure
Feedback-control of quantum systems using continuous state-estimation
We present a formulation of feedback in quantum systems in which the best
estimates of the dynamical variables are obtained continuously from the
measurement record, and fed back to control the system. We apply this method to
the problem of cooling and confining a single quantum degree of freedom, and
compare it to current schemes in which the measurement signal is fed back
directly in the manner usually considered in existing treatments of quantum
feedback. Direct feedback may be combined with feedback by estimation, and the
resulting combination, performed on a linear system, is closely analogous to
classical LQG control theory with residual feedback.Comment: 12 pages, multicol revtex, revised and extende
Influence of a classical homogeneous gravitational field on dissipative dynamics of the Jaynes-Cummings model with phase damping
In this paper, we study the dissipative dynamics of the Jaynes-Cummings model
with phase damping in the presence of a classical homogeneous gravitational
field. The model consists of a moving two-level atom simultaneously exposed to
the gravitational field and a single-mode traveling radiation field in the
presence of the phase damping. We present a quantum treatment of the internal
and external dynamics of the atom based on an alternative su(2) dynamical
algebraic structure. By making use of the super-operator technique, we obtain
the solution of the master equation for the density operator of the quantum
system, under the Markovian approximation. Assuming that initially the
radiation field is prepared in a Glauber coherent state and the two-level atom
is in the excited state, we investigate the influence of gravity on the
temporal evolution of collapses and revivals of the atomic population
inversion, atomic dipole squeezing, atomic momentum diffusion, photon counting
statistics and quadrature squeezing of the radiation field in the presence of
phase damping.Comment: 25 pages, 15 figure
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