1,363,176 research outputs found
Fast Component-By-Component Construction of Rank-1 Lattice Rules for (Non-)Primes (Part II)
No full textPart I: (this part of the talk by Ronald Cools)
We restate our previous result which showed that it is possible to
construct the generating vector of a rank-1 lattice rule in a fast way,
i.e. O(s n log(n)), with s the number of dimensions and n the number of
points assumed to be prime. Here we explicitly use basic facts from
algebra to exploit the structure of a matrix – which introduces the
crucial cost in the construction – to get a matrix-vector
multiplication in time O(n log(n)) instead of O(n^2). We again stress
the fact that the algorithm works for any tensor product reproducing
kernel Hilbert space.
Part II: (this part of the talk by Dirk Nuyens)
In the second part we generalize the tricks used for primes to
non-primes, by basically falling back to algebraic group theory. In
this way it can be shown that also for a non-prime number of points,
this crucial matrix-vector multiplication can be done in time O(n
log(n)). We conclude that the construction of rank-1 lattice rules in
an arbitrary r.k.h.s. for an arbitrary amount of points can be done in a
fast way of O(s n log(n))
Riding with distraction: Exploring the intention and behaviour of smartphone use while riding among motorcyclists in Vietnam
No full textThe pervasive use of smartphones has significantly contributed to distracted driving, a leading cause of road traffic accidents globally. This study investigates the behavioural intentions and patterns of smartphone use while riding among motorcyclists in Vietnam, integrating the Theory of Planned Behaviour (TPB) with the Stimuli-Organism-Response (SOR) framework to encompass factors such as riding exposure and time pressure. A questionnaire survey was conducted, gathering data from 1,051 young motorcyclists. Using Partial Least Squares Structural Equation Modelling (PLS-SEM), the study identifies high levels of smartphone engagement during riding, driven primarily by Perceived Behavioural Control (PBC), which exhibited a stronger influence on behaviour than Attitudes and Social Norms. Notably, time pressure significantly enhanced the intention to use smartphones, suggesting that riding under time constraints could exacerbate the risk of distracted riding incidents. The findings highlight critical implications for road safety interventions and policy formulation, emphasising the need for targeted educational programmes and stricter enforcement measures to mitigate smartphone-induced distractions among motorcyclists at a higher risk of traffic accidents. The study contributes to understanding distracted riding behaviours in motorcycle-dominant regions, providing a foundation for future research and preventive strategies.This work was supported by grant obtained from Wallonie-Bruxelles International (WBI), Belgium for the project 2.17 (Renforcement des compétences en matière de recherche, d’enseignement et de consultance dans le domaine de la logistique) and by the FNRS, Belgium fund supporting the sabbatical leave of Mario Cools
The retrorubral nucleus: a study on consequences of its dysfunction in cats. Implications for its contribution to symptoms seen in Parkinson's disease
No full textItem does not contain fulltextkun, 17 maart 1998Promotor : Cools, A.R
Taking a style perspective to understand organizational behavior: a four-decade review
No full textTo study whether public sector employees are a different type of employee with different expectations than the private sector employees, we look at differences in the generic dimensions of their psychological contract. Data from a survey of 4956 Belgian employees show that, compared to private sector employees, public sector employees attach less importance to career development opportunities and financial rewards promises, and perceive these promises as less fulfilled. They also perceive social atmosphere and work–life balance as less fulfilled. Furthermore, we observed significant gender differences in the importance and fulfilment of the psychological contract
Large Time Step and DC Stable TD-EFIE Discretized with Implicit Runge-Kutta Methods
No full textThe time domain-electric field integral equation (TD-EFIE) and its differentiated version are widely used to simulate the transient scattering of a time dependent electromagnetic field by a perfect electric conductor (PEC). The time discretization of the TD-EFIE can be achieved by a space-time Galerkin approach or, as it is considered in this contribution, by a convolution quadrature using implicit Runge-Kutta methods. The solution is then computed using the marching-on-in-time (MOT) algorithm. The differentiated TD-EFIE has two problems: 1) the system matrix suffers from ill-conditioning when the time step increases (low frequency breakdown) and 2) it suffers from the DC instability, i.e., the formulation allows for the existence of spurious solenoidal currents that grow slowly in the solution. In this article, we show that 1) and 2) can be alleviated by leveraging quasi-Helmholtz projectors to separate the Helmholtz components of the induced current and rescale them independently. The efficacy of the approach is demonstrated by numerical examples including benchmarks and real-life applications.Numerical Analysi
Going Beyond Counting First Authors in Author Co-citation Analysis
No full textThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Individual differences in the release of newly-synthesised and previously stored accumbal dopamine: a rodent study in low and high responders to novelty.
No full textContains fulltext :
80214.pdf (Publisher’s version ) (Open Access)RU Radboud Universiteit Nijmegen, 08 april 2009Promotor : Cools, A.R.269 p
Breaking bad habits - a meditation on the neurocognitive mechanisms of compulsive behavior
No full textContains fulltext :
173246.pdf (Publisher’s version ) (Open Access)Radboud University, 08 juni 2017Promotor : Cools, R. Co-promotor : Aarts, E
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