13,147 research outputs found
Mapping the train model for earthquakes onto the stochastic sandpile model
We perform a computational study of a variant of the ``train'' model for
earthquakes [PRA 46, 6288 (1992)], where we assume a static friction that is a
stochastic function of position rather than being velocity dependent. The model
consists of an array of blocks coupled by springs, with the forces between
neighbouring blocks balanced by static friction. We calculate the probability,
P(s), of the occurrence of avalanches with a size s or greater, finding that
our results are consistent with the phenomenology and also with previous models
which exhibit a power law over a wide range. We show that the train model may
be mapped onto a stochastic sandpile model and study a variant of the latter
for non-spherical grains. We show that, in this case, the model has critical
behaviour only for grains with large aspect ratio, as was already shown in
experiments with real ricepiles. We also demonstrate a way to introduce
randomness in a physically motivated manner into the model.Comment: 14 pages and 6 figures. Accepted in European Physical Journal
Building up Undergraduate Skills – empirical evidence from a Portuguese University
This study presents preliminary results of the PSP Project, addressing students' soft skills development within the context of HEI. Theoretical framework is grounded in Person-Environment Fit theories (Rounds & Hesketh, 1994), and also in Evans (2001) starfish model. Study 1 aimed to identify Economics and Business graduates' Market-Valued Skills Profile, collecting data through semi-structured interviews with HR managers and former students focus groups. Study 2 assessed students' confidence level regarding skills using a self-report questionnaire (Miles & Grummon, 2006). Career development representations were also assessed (Savickas, 2002; Gonçalves, 2006). Additional data was collected through open-ended questions focusing on work and other extracurricular experiences. Results from Study 1 highlight soft skills as multidimensional construct where different interrelated skills contribute to graduates' employability. Study 2 reveals students' positive self-perception regarding those skills, although limited vocational experiences were reported.Soft Skills, Career development, higher education students; employability
Lattice Simulation of Nuclear Multifragmentation
Motivated by the decade-long debate over the issue of criticality supposedly
observed in nuclear multifragmentation, we propose a dynamical lattice model to
simulate the phenomenon. Its Ising Hamiltonian mimics a short range attractive
interaction which competes with a thermal-like dissipative process. The results
here presented, generated through an event-by-event analysis, are in agreement
with both experiment and those produced by a percolative (non-dynamical) model.Comment: 8 pages, 3 figure
Historical Perspective and Innovations in Penile Urethroplasty
Penile urethral strictures are common and impact on quality of life and health-care costs. Management of penile urethral strictures is complex and depends on the physical characteristics of the stricture. Contemporary studies show no difference between urethral dilation and internal urethrotomy in terms of long-term outcomes. Overall, long-term success rates range from 20 to 30%. However, their recurrence rate is greater for men with longer strictures, penile urethral strictures, multiple strictures, presence of infection, or history of prior procedures, which make them less cost-effective. Surgical urethroplasty is associated with higher long-term success rates, averaging from 85 to 90%, mostly in virgin or noncomplex cases. Historically, modern urethral reconstruction has evolved from 1950s with the revolutionary introduction of Johanson’s technique for staged urethral reconstruction. Since then, many techniques have been developed and employed for urethroplasty, depending on the location, length, and character of the stricture. Successful management of urethral strictures requires detailed knowledge of anatomy, pathophysiology, proper patient selection, and reconstructive techniques
Congruences and ideals on Boolean modules: a heterogeneous point of view
Definitions for heterogeneous congruences and heterogeneous ideals on
a Boolean module M are given and the respective lattices CongM and IdeM are
presented. A characterization of the simple Boolean modules is achieved differing
from that given by Brink in a homogeneous approach. We construct the smallest
and the greatest modular congruence having the same Boolean part. The same is
established for modular ideals. The notions of kernel of a modular congruence and
the congruence induced by a modular ideal are introduced to describe an isomorphism
between CongM and IdeM. This isomorphism leads us to conclude that
the class of the Boolean module is ideal determined
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