4,348 research outputs found
When distraction holds relevance : a prospective memory benefit for older adults
Evidence is accumulating to show that age-related increases in susceptibility to distracting information can benefit older more than young adults in several cognitive tasks. Here we focus on prospective memory (i.e., remembering to carry out future intentions) and examine the effect of presenting distracting information that is intention-related as a function of age. Young and older adults performed an ongoing 1-back working memory task to a rapid stream of pictures superimposed with to-be-ignored letter strings. Participants were additionally instructed to respond to target pictures (namely, animals) and, for half of the participants, some strings prior to the targets were intention-related words (i.e., animals). Results showed that presenting intention-related distracting information during the ongoing task was particularly advantageous for target detection in older compared to young adults. Moreover, a prospective memory benefit was observed even for older adults who showed no explicit memory for the target distracter words. We speculate that intention-related distracter information enhanced the accessibility of the prospective memory task and suggest that when distracting information holds relevance to intentions it can serve a compensatory role in prospective remembering in older adults
GIS application in water resources master planning
Due to water scarcity, it is important to organize and regulate water resources
utilization to
satisfy the conflicting water demands and needs. This paper aims to describe a comprehensive
methodology for managing the water sector of a defined urbanized region, using the robust
capabilities of a Geographic Information System (GIS). The proposed methodology is based
on finding alternatives to cover the gap between recent supplies and future demands. Nablus
which is a main governorate located in the north of West Bank, Palestine, was selected as case
study because this area is classified as arid to
semi-arid area.
In fact, GIS integrates hardware,
software, and data for capturing, managing, analyzing, and displaying all forms of geographic
information. The resulted plan of Nablus represents
an example of the proposed methodology
implementation and a
valid framework for the elaboration of a water master plan
Final state interaction in with I=1/2 and 3/2 channels
The final state interaction contribution to decays is computed for the
channel within a light-front relativistic three-body model for
the final state interaction. The rescattering process between the kaon and two
pions in the decay channel is considered. The off-shell decay amplitude is a
solution of a four-dimensional Bethe-Salpeter equation, which is decomposed in
a Faddeev form. The projection onto the light-front of the coupled set of
integral equations is performed via a quasi-potential approach. The S-wave
interaction is introduced in the resonant isospin and the
non-resonant isospin channels. The numerical solution of the light-front
tridimensional inhomogeneous integral equations for the Faddeev components of
the decay amplitude is performed perturbatively. The loop-expansion converges
fast, and the three-loop contribution can be neglected in respect to the
two-loop results for the practical application. The dependence on the model
parameters in respect to the input amplitude at the partonic level is exploited
and the phase found in the experimental analysis, is fitted with an appropriate
choice of the real weights of the isospin components of the partonic amplitude.
The data suggests a small mixture of total isospin to the dominant
one. The modulus of the unsymmetrized decay amplitude, which presents a deep
valley and a following increase for masses above GeV, is fairly
reproduced. This suggests the assignment of the quantum numbers to the
isospin 1/2 resonance
Homogenization and seismic assessment : review and recent trends
The mechanics of masonry structures has been for long
underdeveloped in comparison with other fields of knowledge. Presently,
non-linear analysis is a popular field in masonry research and
advanced computer codes are available for researchers and practitioners.
The chapter presents a discussion of masonry behaviour and
clarifies how to obtain the non-linear data required by the computations.
The chapter also addresses different homogenisation techniques
available in the literature in the linear and rigid-plastic case,
aiming at defining a catalogue and at discussing the advantages and
disadvantages of the different approaches. Special attention is given
to stress assumed models based either on a polynomial expansion
of the micro-stress field or in the discretization of the unit cell by
means of a few constant stress finite elements CST with joints reduced
to interfaces. Finally, the aspects of seismic assessment are
presented and case studies involving the use of macro-block analysis,
static (pushover) analysis and time integration analysis are
discussed.(undefined
Masonry behaviour and modelling
In this Chapter we present the basic experimental facts
on masonry materials and introduce simple and refined models for
masonry. The simple models are essentially macroscopic and based
on the assumption that the material is incapable of sustaining tensile
loads (No-Tension assumption). The refined models account
for the microscopic structure of masonry, modeling the interaction
between the blocks and the interfaces.(undefined
Relativistic Mean-Field Hadronic Models under Nuclear Matter Constraints
Relativistic mean-field (RMF) models have been widely used in the study of
many hadronic frameworks because of several important aspects not always
present in nonrelativistic models, such as intrinsic Lorentz covariance,
automatic inclusion of spin, appropriate saturation mechanism for nuclear
matter, causality and, therefore, no problems related to superluminal speed of
sound. With the aim of identifying the models which best satisfy well known
properties of nuclear matter, we have analyzed parameterizations of seven
different types of RMF models under three different sets of constraints related
to symmetric nuclear matter, pure neutron matter, symmetry energy, and its
derivatives. One of these (SET1) is formed of the same constraints used in a
recent work [M. Dutra et al., Phys. Rev. C 85, 035201 (2012)] in which we
analyzed Skyrme parameterizations. The results pointed to models
consistent with all constraints. By using another set of constraints, namely,
SET2a, formed by the updated versions of the previous one, we found models
approved simultaneously. Finally, in the third set, named SET2b, in which the
values of the constraints are more restrictive, we found consistent models.
Another interesting feature of our analysis is that the results change
dramatically if we do not consider the constraint regarding the volume part of
the isospin incompressibility (). In this case, we have
approved models in SET2a and in SET2b.Comment: 63 pages, 3 figures and 9 tables. Version accepted for publication in
PR
Relativistic Mean-Field Models and Nuclear Matter Constraints
This work presents a preliminary study of 147 relativistic mean-field (RMF)
hadronic models used in the literature, regarding their behavior in the nuclear
matter regime. We analyze here different kinds of such models, namely: (i)
linear models, (ii) nonlinear \sigma^3+\sigma^4 models, (iii)
\sigma^3+\sigma^4+\omega^4 models, (iv) models containing mixing terms in the
fields \sigma and \omega, (v) density dependent models, and (vi) point-coupling
ones. In the finite range models, the attractive (repulsive) interaction is
described in the Lagrangian density by the \sigma (\omega) field. The isospin
dependence of the interaction is modeled by the \rho meson field. We submit
these sets of RMF models to eleven macroscopic (experimental and empirical)
constraints, used in a recent study in which 240 Skyrme parametrizations were
analyzed. Such constraints cover a wide range of properties related to
symmetric nuclear matter (SNM), pure neutron matter (PNM), and both SNM and
PNM.Comment: 3 Pages, submitted for proceedings of XXXV Reuni\~ao de Trabalho
sobre F\'isica Nuclear no Brasil 201
Capacity of a traditional timber mortise and tenon joint
The safety and quality of traditional timber structures mostly depends on the conditions of
their connections. A testing campaign has investigated the behaviour of mortise and tenon timber joint. The
present paper addresses the quantification of the strength capacity of wood-wood mortise and tenon joint by
physical testing of full-scale specimens. In addition, the performance of different non-destructive techniques
(NDT) for assessing global strength is also evaluated. For this three non-destructive methods (ultrasonic testing,
Resistograph and Pilodyn) are considered and the possibility of their application is discussed based on the
application of simple linear regression models. New (NCW) and old (OCW) chestnut wood, obtained from
structural elements belonging to old buildings, is used. Finally, a nonlinear model has been formulated and the
predicted behaviour compared with the behaviour observed in the full-scale experiments, in terms of failure
mode and the ultimate load. The study has shown very good agreement with the experimental values.(undefined
Robust quantum boomerang effect in non-Hermitian systems
Anderson localization is a general phenomenon that applies to a variety of
disordered physical systems. Recently, a novel manifestation of Anderson
localization for wave packets launched with a finite average velocity was
proposed, the Quantum boomerang effect (QBE). This phenomenon predicts that the
disorder-averaged center of mass of a particle initially moves ballistically,
then makes a U-turn, and finally slowly returns to its initial position. The
QBE has been predicted to take place in several Hermitian models with Anderson
localization and has been experimentally observed in the paradigmatic quantum
kicked rotor model. In this work, we investigate the emergence of the QBE in
non-Hermitian systems and clarify the importance of symmetries of the
Hamiltonian and the initial state. We generalize the analytical arguments
available in the literature and show that even in the case of complex spectrum
a boomerang-like behavior can appear in a non-Hermitian system. We confirm our
analytical results through a careful numerical investigation of the dynamics
for several non-Hermitian models. We find that non-Hermiticity leads to the
breakdown of the dynamical relation, though the QBE is preserved. This work
opens up new avenues for future investigations in Anderson localized systems.
The models studied here may be implemented using cold atoms in optical
lattices.Comment: 14 pages, 10 figure
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