298 research outputs found
An operational model for design processes
In this paper we concentrate on the conceptual construction of an architecture of the artefact to be designed (ATBD). The architecture forms the skeleton for all subsequent design stages; design support systems therefore require a representation of this architecture [4]. The fact that design problems are under-defined and open-ended complicates architectural design [5]. Even at the end of the architecture phase many alternatives are left open. It is often necessary to consider several of these alternatives and then to compare their suitabilit
Pattern formation of spherical particles in an oscillating flow
We study the self-organization of spherical particles in an oscillating flow
through experiments inside an oscillating box. The interactions between the
particles and the time-averaged (steady streaming) flow lead to the formation
of either one-particle-thick chains or multiple-particle-wide bands, depending
on the oscillatory conditions. Both the chains and the bands are oriented
perpendicular to the direction of oscillation with a regular spacing between
them. For all our experiments, this spacing is only a function of the relative
particle-fluid excursion length normalized by the particle diameter, ,
implying that it is an intrinsic quantity that is established only by the
hydrodynamics. In contrast, the width of the bands depends on both and
the confinement, characterized by the particle coverage fraction . Using
the relation for the chain spacing, we accurately predict the transition from
one-particle-thick chains to wider bands as a function of and .
Our experimental results are complemented with numerical simulations in which
the flow around the particles is fully resolved. These simulations show that
the regular chain spacing arises from the balance between long-range attractive
and short-range repulsive hydrodynamic interactions, caused by the vortices in
the steady streaming flow. We further show that these vortices induce an
additional attractive interaction at very short range when ,
which stabilizes the multiple-particle-wide bands. Finally, we give a
comprehensive overview of the parameter space where we illustrate the different
regions using our experimental data.Comment: 20 pages, 16 figures, 1 table, to be submitted to Physical Review
Ranking of Fuzzy Similar Faces Using Relevance Matrix and Aggregation Operators
AbstractIn perception based imaging, Sketching With Words (SWW) is a well-established methodology in which the objects of computation are fuzzy geometric objects (f-objects).The problem of facial imaging of criminal on the basis of onlooker statement is not lack of method and measures but the modeling of onlooker(s) mind set. Because the onlooker has to give statements about different human face parts like forehead, eyes, nose, and chin etc.The concept of fuzzy similarity (f-similarity) and proper aggregation of components of face may provide more flexibility to onlooker(s). In proposed work onlooker(s) statement is recorded. Thereafter it is compared with existing statements. The f-similarity with different faces in database is estimated by using ‘as many as possible’ linguistic quantifier. Three types of constraints over size of parts of face ‘small’, ‘medium’, and ‘large’ are considered. Possibilistic constraints with linguistic hedges and negation operator like ‘very long’, ‘not long’, ‘not very long’ etc. are used. Moreover we have generated ranking of alike faces in decreasing order by using the concepts of f-similarity and relevance matrix
From hydrodynamics to dipolar colloids: modeling complex interactions and self-organization with generalized potentials
The self-organization of clusters of particles is a fundamental phenomenon
across various physical systems, including hydrodynamic and colloidal systems.
One example is that of dense spherical particles submerged in a fluid and
subjected to horizontal oscillations. The interaction of the particles with the
oscillating flow leads to the formation of one-particle-thick chains or
multiple-particle-wide bands. In this study, we model the hydrodynamic
interactions between such particles and parallel chains using simplified
potentials. We first focus on the hydrodynamic interactions between chains,
which we characterize using data from numerical simulations. Based on these
interactions, we propose a simplified model potential, called the Siren
potential, which combines the representative hydrodynamic interactions:
short-range attraction, mid-range repulsion, and long-range attraction. Through
one-dimensional Monte Carlo simulations, we successfully replicate the
characteristic patterns observed in hydrodynamic experiments and draw the phase
diagram for the model potential. We extend our analysis to two-dimensional
systems, introducing a dipole-capillary model potential that accounts for both
chain formation and Siren-like chain interactions. This potential is based on
colloidal particles at an interface, where chain formation is driven by an
external electric field inducing a dipole moment parallel to the interface in
each particle. The capillary force contributes the long-range attraction.
Starting with parallel chains, the patterns in the two-dimensional Monte Carlo
simulations of this colloidal system are similar to those observed in the
hydrodynamic experiments. Still, the model potentials help clarify the dynamic
behavior of the particles and chains due to the complex interactions
encountered in both hydrodynamic and colloidal systems, drawing parallels
between them.Comment: 17 pages, 15 figures, under review at Physical Review
Food predictability and social status drive individual resource specializations in a territorial vulture
Food predictability and social status drive individual resource specializations in a territorial vulture
The effect of disgust-related side-effects on symptoms of depression and anxiety in people treated for cancer: a moderated mediation model
As maladaptive disgust responses are linked to mental health problems, and cancer patients
may experience heightened disgust as a result of treatments they receive, we explored the
associations between disgust-related side-effects and symptoms of depression and anxiety in
people treated for cancer. One hundred and thirty two (83 women, Mage = 57.48 years)
participants answered questions about their treatments, side-effects, disgust responding, and
mental health. Experiencing bowel and/or bladder problems, sickness and/or nausea (referred
to here as “core” disgust-related side-effects) was significantly related to greater symptoms of
depression and borderline increased anxiety. Further, these links were explained by a
moderated mediation model, whereby the effects of core disgust side-effects on depression
and anxiety were mediated by (physical and behavioural) self-directed disgust, and disgust
propensity moderated the effect of core disgust side-effects on self-disgust. These findings
stress the importance of emotional responses, like disgust, in psychological adaptation to the
side-effects of cancer treatments
Disgust trumps lust:women’s disgust and attraction towards men is unaffected by sexual arousal
Mating is a double-edged sword. It can have great adaptive benefits, but also high costs, depending on the mate. Disgust is an avoidance reaction that serves the function of discouraging costly mating decisions, for example if the risk of pathogen transmission is high. It should, however, be temporarily inhibited in order to enable potentially adaptive mating. We therefore tested the hypothesis that sexual arousal inhibits disgust if a partner is attractive, but not if he is unattractive or shows signs of disease. In an online experiment, women rated their disgust towards anticipated behaviors with men depicted on photographs. Participants did so in a sexually aroused state and in a control state. The faces varied in attractiveness and the presence of disease cues (blemishes). We found that disease cues and attractiveness, but not sexual arousal, influenced disgust. The results suggest that women feel disgust at sexual contact with unattractive or diseased men independently of their sexual arousal
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