10,807 research outputs found
Exploring Household Saving and Consumption-Smoothing in the Philippines
This paper explores whether or not the saving behavior of Filipino households fits the life-cycle hypothesis. Using pseudo-panels, which are constructed from the public use data files of the Family Income and Expenditures Survey of 1988 to 2000, it shows that consumption rises with the age of the household head and that the consumption profile has been rising for younger cohorts. The regressions indicate that the cohort-independent age effects on consumption simply track those on income across all ages, suggesting that Filipino households do not behave as the life-cycle hypothesis prescribes, possibly because they are liquidity constrained or impatient.consumption smoothing, household savings, household consumption
Exploring Household Saving and Consumption-Smoothing in the Philippines
This paper explores whether or not the saving behavior of Filipino households fits the life-cycle hypothesis. Using pseudo-panels, which are constructed from the public use data files of the Family Income and Expenditures Survey of 1988 to 2000, it shows that consumption rises with the age of the household head and that the consumption profile has been rising for younger cohorts. The regressions indicate that the cohort-independent age effects on consumption simply track those on income across all ages, suggesting that Filipino households do not behave as the life-cycle hypothesis prescribes, possibly because they are liquidity constrained or impatient.consumption smoothing, household savings, household consumption
Spacetime Defects: von K\'arm\'an vortex street like configurations
A special arrangement of spinning strings with dislocations similar to a von
K\'arm\'an vortex street is studied. We numerically solve the geodesic
equations for the special case of a test particle moving along twoinfinite rows
of pure dislocations and also discuss the case of pure spinning defects.Comment: 9 pages, 2figures, CQG in pres
On the gravitational field of static and stationary axial symmetric bodies with multi-polar structure
We give a physical interpretation to the multi-polar Erez-Rozen-Quevedo
solution of the Einstein Equations in terms of bars. We find that each
multi-pole correspond to the Newtonian potential of a bar with linear density
proportional to a Legendre Polynomial. We use this fact to find an integral
representation of the function. These integral representations are
used in the context of the inverse scattering method to find solutions
associated to one or more rotating bodies each one with their own multi-polar
structure.Comment: To be published in Classical and Quantum Gravit
Enriched Long-term Recurrent Convolutional Network for Facial Micro-Expression Recognition
Facial micro-expression (ME) recognition has posed a huge challenge to
researchers for its subtlety in motion and limited databases. Recently,
handcrafted techniques have achieved superior performance in micro-expression
recognition but at the cost of domain specificity and cumbersome parametric
tunings. In this paper, we propose an Enriched Long-term Recurrent
Convolutional Network (ELRCN) that first encodes each micro-expression frame
into a feature vector through CNN module(s), then predicts the micro-expression
by passing the feature vector through a Long Short-term Memory (LSTM) module.
The framework contains two different network variants: (1) Channel-wise
stacking of input data for spatial enrichment, (2) Feature-wise stacking of
features for temporal enrichment. We demonstrate that the proposed approach is
able to achieve reasonably good performance, without data augmentation. In
addition, we also present ablation studies conducted on the framework and
visualizations of what CNN "sees" when predicting the micro-expression classes.Comment: Published in Micro-Expression Grand Challenge 2018, Workshop of 13th
IEEE Facial & Gesture 201
Time-scales of close-in exoplanet radio emission variability
We investigate the variability of exoplanetary radio emission using stellar
magnetic maps and 3D field extrapolation techniques. We use a sample of hot
Jupiter hosting stars, focusing on the HD 179949, HD 189733 and tau Boo
systems. Our results indicate two time-scales over which radio emission
variability may occur at magnetised hot Jupiters. The first is the synodic
period of the star-planet system. The origin of variability on this time-scale
is the relative motion between the planet and the interplanetary plasma that is
co-rotating with the host star. The second time-scale is the length of the
magnetic cycle. Variability on this time-scale is caused by evolution of the
stellar field. At these systems, the magnitude of planetary radio emission is
anticorrelated with the angular separation between the subplanetary point and
the nearest magnetic pole. For the special case of tau Boo b, whose orbital
period is tidally locked to the rotation period of its host star, variability
only occurs on the time-scale of the magnetic cycle. The lack of radio
variability on the synodic period at tau Boo b is not predicted by previous
radio emission models, which do not account for the co-rotation of the
interplanetary plasma at small distances from the star.Comment: 10 pages, 7 figures, 2 tables, accepted in MNRA
Less is More: Micro-expression Recognition from Video using Apex Frame
Despite recent interest and advances in facial micro-expression research,
there is still plenty room for improvement in terms of micro-expression
recognition. Conventional feature extraction approaches for micro-expression
video consider either the whole video sequence or a part of it, for
representation. However, with the high-speed video capture of micro-expressions
(100-200 fps), are all frames necessary to provide a sufficiently meaningful
representation? Is the luxury of data a bane to accurate recognition? A novel
proposition is presented in this paper, whereby we utilize only two images per
video: the apex frame and the onset frame. The apex frame of a video contains
the highest intensity of expression changes among all frames, while the onset
is the perfect choice of a reference frame with neutral expression. A new
feature extractor, Bi-Weighted Oriented Optical Flow (Bi-WOOF) is proposed to
encode essential expressiveness of the apex frame. We evaluated the proposed
method on five micro-expression databases: CAS(ME), CASME II, SMIC-HS,
SMIC-NIR and SMIC-VIS. Our experiments lend credence to our hypothesis, with
our proposed technique achieving a state-of-the-art F1-score recognition
performance of 61% and 62% in the high frame rate CASME II and SMIC-HS
databases respectively.Comment: 14 pages double-column, author affiliations updated, acknowledgment
of grant support adde
A new orthogonalization procedure with an extremal property
Various methods of constructing an orthonomal set out of a given set of
linearly independent vectors are discussed. Particular attention is paid to the
Gram-Schmidt and the Schweinler-Wigner orthogonalization procedures. A new
orthogonalization procedure which, like the Schweinler- Wigner procedure, is
democratic and is endowed with an extremal property is suggested.Comment: 7 pages, latex, no figures, To appear in J. Phys
Investigation of the transient fuel preburner manifold and combustor
A computational fluid dynamics (CFD) model with finite rate reactions, FDNS, was developed to study the start transient of the Space Shuttle Main Engine (SSME) fuel preburner (FPB). FDNS is a time accurate, pressure based CFD code. An upwind scheme was employed for spatial discretization. The upwind scheme was based on second and fourth order central differencing with adaptive artificial dissipation. A state of the art two-equation k-epsilon (T) turbulence model was employed for the turbulence calculation. A Pade' Rational Solution (PARASOL) chemistry algorithm was coupled with the point implicit procedure. FDNS was benchmarked with three well documented experiments: a confined swirling coaxial jet, a non-reactive ramjet dump combustor, and a reactive ramjet dump combustor. Excellent comparisons were obtained for the benchmark cases. The code was then used to study the start transient of an axisymmetric SSME fuel preburner. Predicted transient operation of the preburner agrees well with experiment. Furthermore, it was also found that an appreciable amount of unburned oxygen entered the turbine stages
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