6,912 research outputs found
Investorsâ behaviour in the Chinese Stock Exchanges: Empirical Evidence in a Systemic Approach
This paper investigates the Chinese mainland Stock Exchanges and their following interconnecting features: saversâ attitude towards stock investments, investorsâ trading behaviour and stock returns explanations. We evaluate the effectiveness of the recent efforts made by the Chinese authorities to improve the level of legal protections for shareholders and the opening-up of the Chinese Stock Markets to foreign investors. The whole analysis is carried out through a system of simultaneous equations. The main results are that Chinese shareholders and stock markets are mostly driven by emotional behaviour. Stock market returns are barely influenced by the overall Chinese economic booming, but reveal the presence of speculative influences. Investorsâ behaviour, as well as general trading activities, hardly seems to be affected by the legal framework introduced by the national Authorities.Chinese Stock Exchanges, shareholdersâ rights, corporate governance, investorsâ behaviour, system of simultaneous equations
Energy-Based Optimal Ranking of the Interior Modes for Reduced-Order Models under Periodic Excitation
This paper introduces a novel method for ranking and selecting the interior modes to be retained in the Craig-Bampton model reduction, in the case of linear vibrating systems under periodic excitation. The aim of the method is to provide an effective ranking of such modes and hence an optimal sequence according to which the interior modes should be progressively included to achieve a desired accuracy of the reduced-order model at the frequencies of interest, while keeping model dimensions to a minimum. An energy-based ranking (EBR) method is proposed, which exploits analytical coefficients to evaluate the contribution of each interior mode to the forced response of the full-order system. The application of the method to two representative systems is discussed: an ultrasonic horn and a vibratory feeder. The results show that the EBR method provides a very effective ranking of the most important interior modes and that it outperforms other state-of-the-art benchmark techniques
Nonlinear Adjustment in US Bond Yields: an Empirical Analysis with Conditional Heteroskedasticity
Starting from the work by Campbell and Shiller (1987), empirical analysis of interest rates has been conducted in the framework of cointegration. However, parts of this approach have been questioned recently, as the adjustment mechanism may not follow a simple linear rule; another line of criticism points out that stationarity of the spreads is difficult to maintain empirically. In this paper, we analyse data on US bond yields by means of an augmented VAR specification which approximates a generic nonlinear adjustment model. We argue that nonlinearity captures macro information via the shape of the yield curve and thus provides an alternative explanation for some findings recently appeared in the literature. Moreover, we show how conditional heteroskedasticity can be taken into account via GARCH specifications for the conditional variance, either univariate and multivariate.interest rates, cointegration, nonlinear adjustment, conditional heteroskedasticity
Longitudinal quantum plasmons in copper, gold, and silver
The propagation of plasmonic waves in various metallic quantum nanostructures
have considered attention for their applications in technology. The quantum
plasmonic properties of metallic nanostructures in the quantum size regime have
been difficult to describe by an appropriate model. Here the nonlocal quantum
plasmons are investigated in the most important metals of copper, gold, and
silver. Dispersion properties of these metals and propagation of longitudinal
quantum plasmons in the high photon energy regime are studied by a new model of
nonlocal quantum dielectric permittivity. The epsilon near zero properties are
investigated and the spectrum and the damping rate of the longitudinal quantum
plasmons are obtained in these metals. The quantum plasmon s wave function is
shown for both classical and quantum limits. It is shown that silver is the
most appropriate for quantum metallic structures in the development of next
generation of quantum optical and sensing technologies, due to low intrinsic
loss
Neutron star bulk viscosity, "spin-flip" and GW emission of newly born magnetars
The viscosity-driven "spin-flip" instability in newborn magnetars with
interior toroidal magnetic fields is re-examined. We calculate the bulk
viscosity coefficient () of cold, matter in neutron stars
(NS), for selected values of the nuclear symmetry energy and in the regime
where -equilibration is slower than characteristic oscillation periods.
We show that: i) is larger than previously assumed and the instability
timescale correspondingly shorter; ii) for a magnetically-induced ellipticity
, typically expected in newborn
magnetars, spin-flip occurs for initial spin periods ms, with
some dependence on the NS equation of state (EoS). We then calculate the
detectability of GW signals emitted by newborn magnetars subject to
"spin-flip", by accounting also for the reduction in range resulting from
realistic signal searches. For an optimal range of , and birth spin period ms, we estimate an horizon
of Mpc, and Mpc, for Advanced and third generation
interferometers at design sensitivity, respectively. A supernova (or a
kilonova) is expected as the electromagnetic counterpart of such GW events.
Outside of the optimal range for GW emission, EM torques are more efficient in
extracting the NS spin energy, which may power even brighter EM transients.Comment: 10 pages, 4 figures, accepted for publication in MNRA
Effect of Martian Suspended Dust on Albedo Measurements from the MGS-TES Data
Suspended dust on Mars influences albedo measurements by orbiting instruments, but not necessary the real surface albedo. The aim of this study is to characterize the role of suspended aerosols on albedo measurement by remote sensing instruments
Somatic, but not cognitive-affective, symptoms are associated with reduced heart rate variability in individuals with dysphoria
Background: Somatic, but not cognitive-affective, symptoms of depression have been associated with reduced heart rate variability (HRV), and with poor prognosis in cardiovascular patients. However, factors concomitant with cardiovascular diseases may confound the relationship between somatic symptoms of depression and reduced HRV. Therefore, this study examined whether reduced HRV was differentially associated with cognitive-affective and somatic symptoms of depression in medically healthy individuals with and without dysphoria. Methods: Self-reported cognitive-affective and somatic symptoms as measured with the Beck Depression Inventory-II (BDI-II) questionnaire and time and frequency domain parameters of HRV were collected in 62 medically healthy individuals, of whom 25 with and 37 without dysphoria. Results: Somatic, but not cognitive-affective, symptoms of depression were inversely associated with standard deviation of NN intervals (SDNN) (beta = -0.476, p .24). Conclusions: By showing that the relationship between somatic depressive symptoms and reduced HRV extends to medically healthy individuals with dysphoria, the present findings suggest that this association is independent of factors concomitant with cardiovascular diseases. The present study also suggests that individuals with somatic rather than cognitive-affective subsets of depressive symptoms may be at greater risk for developing cardiovascular diseases
- âŚ