220 research outputs found
Divorce decisions, divorce laws and social norms
This article focuses on the three way relationship between change in divorce law, evolution of divorce rate and evolution of the cultural acceptance of divorce. We consider a heterogeneous population in which individuals differ in terms of the subjective loss they suffer when divorced, this loss being associated with stigmatizing social norms. The proportion of each type of individual evolves endogenously through a cultural transmission process. Divorce law is chosen by majority voting between two alternatives : mutual consent and unilateral divorce. In this framework, evolutions of divorce rate and divorce law may be jointly affected by the cultural dynamics within the society. In particular, we are able to reproduce the fact that divorce rate often raises before a legislation change. Indeed, the shift from consensual to unilateral divorce has an accelerating effect on the increase in divorce rate but is not the driving force behind this evolution.Marriage and divorce, divorce legislation, cultural evolution, social norms.
Household Behavior and Social Norms : A Conjugal Contract Model
We present a model of household behavior to explore the complex interactions between the decision-making process within the household and social norms. The household is viewed as two separate spheres – the female and the male – both linked by a public good and a "conjugal contract" trough which spouses exchange resources. The conjugal contract negotiated within the couple is partly influenced by social norms given the conformism of individuals. Social norms are endogenously determined as the average conjugal contract. We find that the closer spouses' wages are in the labor market, the more equally they share household tasks. Wage policies promoting gender wage equality lead all couples to renegotiate the terms of their conjugal contract, which in turn changes social norms. Even though spouses aim at maximizing the household's welfare, the resulting equilibrium allocation is not Pareto efficient and inefficiency increases with social conformism.Conjugal contract ; social norms ; wage discrimination ; household behavior ; intra-household decision-making
First-principles calculations of heat capacities of ultrafast laser-excited electrons in metals
Ultrafast laser excitation can induce fast increases of the electronic
subsystem temperature. The subsequent electronic evolutions in terms of band
structure and energy distribution can determine the change of several
thermodynamic properties, including one essential for energy deposition; the
electronic heat capacity. Using density functional calculations performed at
finite electronic temperatures, the electronic heat capacities dependent on
electronic temperatures are obtained for a series of metals, including free
electron like, transition and noble metals. The effect of exchange and
correlation functionals and the presence of semicore electrons on electronic
heat capacities are first evaluated and found to be negligible in most cases.
Then, we tested the validity of the free electron approaches, varying the
number of free electrons per atom. This shows that only simple metals can be
correctly fitted with these approaches. For transition metals, the presence of
localized d electrons produces a strong deviation toward high energies of the
electronic heat capacities, implying that more energy is needed to thermally
excite them, compared to free sp electrons. This is attributed to collective
excitation effects strengthened by a change of the electronic screening at high
temperature
Ultrafast Surface Plasmonic Switch in Non-Plasmonic Metals
We demonstrate that ultrafast carrier excitation can drastically affect
electronic structures and induce brief surface plasmonic response in
non-plasmonic metals, potentially creating a plasmonic switch. Using
first-principles molecular dynamics and Kubo-Greenwood formalism for
laser-excited tungsten we show that carrier heating mobilizes d electrons into
collective inter and intraband transitions leading to a sign flip in the
imaginary optical conductivity, activating plasmonic properties for the initial
non-plasmonic phase. The drive for the optical evolution can be visualized as
an increasingly damped quasi-resonance at visible frequencies for pumping
carriers across a chemical potential located in a d-band pseudo-gap with
energy-dependent degree of occupation. The subsequent evolution of optical
indices for the excited material is confirmed by time-resolved ultrafast
ellipsometry. The large optical tunability extends the existence spectral
domain of surface plasmons in ranges typically claimed in laser self-organized
nanostructuring. Non-equilibrium heating is thus a strong factor for
engineering optical control of evanescent excitation waves, particularly
important in laser nanostructuring strategies
How Can Gender Discrimination Explain Fertility Behaviors and Family-friends Policies ?
This paper focuses on the interaction between gender discrimination and household decisions. It develops a general equilibrium model with endogenous fertility, endogenous labor supply and endogenous size of government spending. Family policies are assumed to decrease the time that parents spend on their children. The model shows that gender discrimination may explain differences in household decisions between countries. The solution shows a U-shaped relationship between fertility and gender discrimination. An increase in the discrimination level implies a related decrease in fertility, women's participation in the labor force and in family-friendly policies.Discrimination, gender, fertility, labor supply, public policies.
Y algo más acerca de Cervantes: «¡Eso, no! ¡... Así es la verdad!» «Las solícitas y discretas abejas»
Two-temperature relaxation and melting after absorption of femtosecond laser pulse
The theory and experiments concerned with the electron-ion thermal relaxation
and melting of overheated crystal lattice constitute the subject of this paper.
The physical model includes two-temperature equation of state, many-body
interatomic potential, the electron-ion energy exchange, electron thermal
conductivity, and optical properties of solid, liquid, and two phase
solid-liquid mixture. Two-temperature hydrodynamics and molecular dynamics
codes are used. An experimental setup with pump-probe technique is used to
follow evolution of an irradiated target with a short time step 100 fs between
the probe femtosecond laser pulses. Accuracy of measurements of reflection
coefficient and phase of reflected probe light are ~1% and \sim 1\un{nm},
respectively. It is found that,
{\it firstly}, the electron-electron collisions make a minor contribution to
a light absorbtion in solid Al at moderate intensities;
{\it secondly}, the phase shift of a reflected probe results from heating of
ion subsystem and kinetics of melting of Al crystal during 0
where is time delay between the pump and probe pulses measured from the
maximum of the pump;
{\it thirdly} the optical response of Au to a pump shows a marked contrast to
that of Al on account of excitation of \textit{d}-electronsComment: 6th International Conference on Photo-Excited Processes and
Applications 9-12 Sep 2008, Sapporo, Japan, http://www.icpepa6.com, the
contributed paper will be published in Applied Surface Science(2009
Get rid of inline assembly through verification-oriented lifting
Formal methods for software development have made great strides in the last
two decades, to the point that their application in safety-critical embedded
software is an undeniable success. Their extension to non-critical software is
one of the notable forthcoming challenges. For example, C programmers regularly
use inline assembly for low-level optimizations and system primitives. This
usually results in driving state-of-the-art formal analyzers developed for C
ineffective. We thus propose TInA, an automated, generic, trustable and
verification-oriented lifting technique turning inline assembly into
semantically equivalent C code, in order to take advantage of existing C
analyzers. Extensive experiments on real-world C code with inline assembly
(including GMP and ffmpeg) show the feasibility and benefits of TInA
Interface Compliance of Inline Assembly: Automatically Check, Patch and Refine
Inline assembly is still a common practice in low-level C programming,
typically for efficiency reasons or for accessing specific hardware resources.
Such embedded assembly codes in the GNU syntax (supported by major compilers
such as GCC, Clang and ICC) have an interface specifying how the assembly codes
interact with the C environment. For simplicity reasons, the compiler treats
GNU inline assembly codes as blackboxes and relies only on their interface to
correctly glue them into the compiled C code. Therefore, the adequacy between
the assembly chunk and its interface (named compliance) is of primary
importance, as such compliance issues can lead to subtle and hard-to-find bugs.
We propose RUSTInA, the first automated technique for formally checking inline
assembly compliance, with the extra ability to propose (proven) patches and
(optimization) refinements in certain cases. RUSTInA is based on an original
formalization of the inline assembly compliance problem together with novel
dedicated algorithms. Our prototype has been evaluated on 202 Debian packages
with inline assembly (2656 chunks), finding 2183 issues in 85 packages -- 986
significant issues in 54 packages (including major projects such as ffmpeg or
ALSA), and proposing patches for 92% of them. Currently, 38 patches have
already been accepted (solving 156 significant issues), with positive feedback
from development teams
- …