José Tavares - Academia.edu (original) (raw)

Papers by José Tavares

Research paper thumbnail of New challenges in teaching introductory programming courses: a case study

34th Annual Frontiers in Education, 2004. FIE 2004., 2004

The Department of Educational Sciences and the Department of Electronic & Telecommunications at t... more The Department of Educational Sciences and the Department of Electronic & Telecommunications at the University of Aveiro (Portugal) have been working together with the Department of Computer & Information Sciences at the University of Strathclyde (UK), with the aim of improving the teaching quality of introductory programming courses and, indirectly, the academic success of their students. Over the past two years, data has been collected through interviews and questionnaires, to better understand the organization of the different courses and approaches to teaching. The present paper discusses how the organization of introductory programming courses in each institution reflects the teaching philosophy of the members of staff and also how course organization and teaching strategy relate to the students' attitudes to learning and their motivation for course involvement.

Research paper thumbnail of Comparison of condylar displacement between three biotypological facial groups by using mounted models and a mandibular position indicator

The Korean Journal of Orthodontics, 2014

Objective: Facial-type associated variations in diagnostic features have several implications in ... more Objective: Facial-type associated variations in diagnostic features have several implications in orthodontics. For example, in hyperdivergent craniofacial types, growth imbalances are compensated by displacement of the condyle. When diagnosis and treatment planning involves centric relation (CR), detailed knowledge of the condylar position is desirable. The present study aimed to measure condylar displacement (CD) between CR and maximum intercuspation in three facial types of an asymptomatic orthodontic population. Methods:

Research paper thumbnail of Phase diagrams of binary mixtures of patchy colloids with distinct numbers and types of patches: The empty fluid regime

The Journal of Chemical Physics, 2011

We investigate the effect of distinct bonding energies on the onset of criticality of low functio... more We investigate the effect of distinct bonding energies on the onset of criticality of low functionality fluid mixtures. We focus on mixtures of particles with two and three patches as this includes the mixture where 'empty' fluids were originally reported. In addition to the number of patches, the species differ in the type of patches or bonding sites. For simplicity, we consider that the patches on each species are identical: one species has 3 patches of type A and the other 2 patches of type B. We have found a rich phase behaviour with closed miscibility gaps, liquid-liquid demixing and negative azeotropes. Liquid-liquid demixing was found to preempt the 'empty' fluid regime, of these mixtures, when the AB bonds are weaker than the AA or BB bonds. By contrast, mixtures in this class exhibit 'empty' fluid behaviour when the AB bonds are stronger than at least one of the other two. Mixtures with bonding energies ǫ BB = ǫ AB and ǫ AA < ǫ BB , were found to exhibit an unusual negative azeotrope.

Research paper thumbnail of Properties of patchy colloidal particles close to a surface: A Monte Carlo and density functional study

The Journal of Chemical Physics, 2012

We investigate the behavior of a patchy particle model close to a hard-wall via Monte Carlo simul... more We investigate the behavior of a patchy particle model close to a hard-wall via Monte Carlo simulation and density functional theory (DFT). Two DFT approaches, based on the homogeneous and inhomogeneous versions of Wertheim's first order perturbation theory for the association free energy are used. We evaluate, by simulation and theory, the equilibrium bulk phase diagram of the fluid and analyze the surface properties for two isochores, one of which is close to the liquid side of the gas-liquid coexistence curve. We find that the density profile near the wall crosses over from a typical high-temperature adsorption profile to a low-temperature desorption one, for the isochore close to coexistence. We relate this behavior to the properties of the bulk network liquid and find that the theoretical descriptions are reasonably accurate in this regime. At very low temperatures, however, an almost fully bonded network is formed, and the simulations reveal a second adsorption regime which is not captured by DFT. We trace this failure to the neglect of orientational correlations of the particles, which are found to exhibit surface induced orientational order in this regime.

Research paper thumbnail of Quantitative description of the self-assembly of patchy particles into chains and rings

The Journal of Chemical Physics, 2012

We numerically study a simple fluid composed of particles having a hard-core repulsion complement... more We numerically study a simple fluid composed of particles having a hard-core repulsion complemented by two patchy attractive sites on the particle poles. An appropriate choice of the patch angular width allows for the formation of ring structures which, at low temperatures and low densities, compete with the growth of linear aggregates. The simplicity of the model makes it possible to compare simulation results and theoretical predictions based on the Wertheim perturbation theory, specialized to the case in which ring formation is allowed. Such a comparison offers a unique framework for establishing the quality of the analytic predictions. We find that the Wertheim theory describes remarkably well the simulation results.

Research paper thumbnail of Branching points in the low-temperature dipolar hard sphere fluid

The Journal of Chemical Physics, 2013

In this contribution, we investigate the low-temperature, low-density behaviour of dipolar hard-s... more In this contribution, we investigate the low-temperature, low-density behaviour of dipolar hard-sphere (DHS) particles, i.e., hard spheres with dipoles embedded in their centre. We aim at describing the DHS fluid in terms of a network of chains and rings (the fundamental clusters) held together by branching points (defects) of different nature. We first introduce a systematic way of classifying inter-cluster connections according to their topology, and then employ this classification to analyse the geometric and thermodynamic properties of each class of defects, as extracted from state-of-the-art equilibrium Monte Carlo simulations. By computing the average density and energetic cost of each defect class, we find that the relevant contribution to inter-cluster interactions is indeed provided by (rare) three-way junctions and by four-way junctions arising from parallel or anti-parallel locally linear aggregates. All other (numerous) defects are either intra-cluster or associated to low cluster-cluster interaction energies, suggesting that these defects do not play a significant part in the thermodynamic description of the self-assembly processes of dipolar hard spheres.

Research paper thumbnail of Computing the phase diagram of binary mixtures: A patchy particle case study

The Journal of Chemical Physics, 2013

We investigate the phase behaviour of 2D mixtures of bi-functional and three-functional patchy pa... more We investigate the phase behaviour of 2D mixtures of bi-functional and three-functional patchy particles and 3D mixtures of bi-functional and tetra-functional patchy particles by means of Monte Carlo simulations and Wertheim theory. We start by computing the critical points of the pure systems and then we investigate how the critical parameters change upon lowering the temperature. We extend the Successive Umbrella Sampling method to mixtures to make it possible to extract information about the phase behaviour of the system at a fixed temperature for the whole range of densities and compositions of interest.

Research paper thumbnail of Simple thermodynamics of jet engines

American Journal of Physics, 2010

ABSTRACT

Research paper thumbnail of Architecting Scalability for Massively Multiplayer Online Gaming Experiences

… : Changing Views-Worlds in Play. Digital …, 2005

Rui Gil CISUC, University of Coimbra Polo II – Universidade de Coimbra, 3030-290 Coimbra, Portuga... more Rui Gil CISUC, University of Coimbra Polo II – Universidade de Coimbra, 3030-290 Coimbra, Portugal +351-23979000 rgil@dei.uc.pt ... José Pedro Tavares CISUC, University of Coimbra Polo II – Universidade de Coimbra, 3030-290 Coimbra, Portugal +351-...

Research paper thumbnail of New challenges in teaching introductory programming courses: a case study

34th Annual Frontiers in Education, 2004. FIE 2004., 2004

The Department of Educational Sciences and the Department of Electronic & Telecommunications at t... more The Department of Educational Sciences and the Department of Electronic & Telecommunications at the University of Aveiro (Portugal) have been working together with the Department of Computer & Information Sciences at the University of Strathclyde (UK), with the aim of improving the teaching quality of introductory programming courses and, indirectly, the academic success of their students. Over the past two years, data has been collected through interviews and questionnaires, to better understand the organization of the different courses and approaches to teaching. The present paper discusses how the organization of introductory programming courses in each institution reflects the teaching philosophy of the members of staff and also how course organization and teaching strategy relate to the students' attitudes to learning and their motivation for course involvement.

Research paper thumbnail of Comparison of condylar displacement between three biotypological facial groups by using mounted models and a mandibular position indicator

The Korean Journal of Orthodontics, 2014

Objective: Facial-type associated variations in diagnostic features have several implications in ... more Objective: Facial-type associated variations in diagnostic features have several implications in orthodontics. For example, in hyperdivergent craniofacial types, growth imbalances are compensated by displacement of the condyle. When diagnosis and treatment planning involves centric relation (CR), detailed knowledge of the condylar position is desirable. The present study aimed to measure condylar displacement (CD) between CR and maximum intercuspation in three facial types of an asymptomatic orthodontic population. Methods:

Research paper thumbnail of Phase diagrams of binary mixtures of patchy colloids with distinct numbers and types of patches: The empty fluid regime

The Journal of Chemical Physics, 2011

We investigate the effect of distinct bonding energies on the onset of criticality of low functio... more We investigate the effect of distinct bonding energies on the onset of criticality of low functionality fluid mixtures. We focus on mixtures of particles with two and three patches as this includes the mixture where 'empty' fluids were originally reported. In addition to the number of patches, the species differ in the type of patches or bonding sites. For simplicity, we consider that the patches on each species are identical: one species has 3 patches of type A and the other 2 patches of type B. We have found a rich phase behaviour with closed miscibility gaps, liquid-liquid demixing and negative azeotropes. Liquid-liquid demixing was found to preempt the 'empty' fluid regime, of these mixtures, when the AB bonds are weaker than the AA or BB bonds. By contrast, mixtures in this class exhibit 'empty' fluid behaviour when the AB bonds are stronger than at least one of the other two. Mixtures with bonding energies ǫ BB = ǫ AB and ǫ AA < ǫ BB , were found to exhibit an unusual negative azeotrope.

Research paper thumbnail of Properties of patchy colloidal particles close to a surface: A Monte Carlo and density functional study

The Journal of Chemical Physics, 2012

We investigate the behavior of a patchy particle model close to a hard-wall via Monte Carlo simul... more We investigate the behavior of a patchy particle model close to a hard-wall via Monte Carlo simulation and density functional theory (DFT). Two DFT approaches, based on the homogeneous and inhomogeneous versions of Wertheim's first order perturbation theory for the association free energy are used. We evaluate, by simulation and theory, the equilibrium bulk phase diagram of the fluid and analyze the surface properties for two isochores, one of which is close to the liquid side of the gas-liquid coexistence curve. We find that the density profile near the wall crosses over from a typical high-temperature adsorption profile to a low-temperature desorption one, for the isochore close to coexistence. We relate this behavior to the properties of the bulk network liquid and find that the theoretical descriptions are reasonably accurate in this regime. At very low temperatures, however, an almost fully bonded network is formed, and the simulations reveal a second adsorption regime which is not captured by DFT. We trace this failure to the neglect of orientational correlations of the particles, which are found to exhibit surface induced orientational order in this regime.

Research paper thumbnail of Quantitative description of the self-assembly of patchy particles into chains and rings

The Journal of Chemical Physics, 2012

We numerically study a simple fluid composed of particles having a hard-core repulsion complement... more We numerically study a simple fluid composed of particles having a hard-core repulsion complemented by two patchy attractive sites on the particle poles. An appropriate choice of the patch angular width allows for the formation of ring structures which, at low temperatures and low densities, compete with the growth of linear aggregates. The simplicity of the model makes it possible to compare simulation results and theoretical predictions based on the Wertheim perturbation theory, specialized to the case in which ring formation is allowed. Such a comparison offers a unique framework for establishing the quality of the analytic predictions. We find that the Wertheim theory describes remarkably well the simulation results.

Research paper thumbnail of Branching points in the low-temperature dipolar hard sphere fluid

The Journal of Chemical Physics, 2013

In this contribution, we investigate the low-temperature, low-density behaviour of dipolar hard-s... more In this contribution, we investigate the low-temperature, low-density behaviour of dipolar hard-sphere (DHS) particles, i.e., hard spheres with dipoles embedded in their centre. We aim at describing the DHS fluid in terms of a network of chains and rings (the fundamental clusters) held together by branching points (defects) of different nature. We first introduce a systematic way of classifying inter-cluster connections according to their topology, and then employ this classification to analyse the geometric and thermodynamic properties of each class of defects, as extracted from state-of-the-art equilibrium Monte Carlo simulations. By computing the average density and energetic cost of each defect class, we find that the relevant contribution to inter-cluster interactions is indeed provided by (rare) three-way junctions and by four-way junctions arising from parallel or anti-parallel locally linear aggregates. All other (numerous) defects are either intra-cluster or associated to low cluster-cluster interaction energies, suggesting that these defects do not play a significant part in the thermodynamic description of the self-assembly processes of dipolar hard spheres.

Research paper thumbnail of Computing the phase diagram of binary mixtures: A patchy particle case study

The Journal of Chemical Physics, 2013

We investigate the phase behaviour of 2D mixtures of bi-functional and three-functional patchy pa... more We investigate the phase behaviour of 2D mixtures of bi-functional and three-functional patchy particles and 3D mixtures of bi-functional and tetra-functional patchy particles by means of Monte Carlo simulations and Wertheim theory. We start by computing the critical points of the pure systems and then we investigate how the critical parameters change upon lowering the temperature. We extend the Successive Umbrella Sampling method to mixtures to make it possible to extract information about the phase behaviour of the system at a fixed temperature for the whole range of densities and compositions of interest.

Research paper thumbnail of Simple thermodynamics of jet engines

American Journal of Physics, 2010

ABSTRACT

Research paper thumbnail of Architecting Scalability for Massively Multiplayer Online Gaming Experiences

… : Changing Views-Worlds in Play. Digital …, 2005

Rui Gil CISUC, University of Coimbra Polo II – Universidade de Coimbra, 3030-290 Coimbra, Portuga... more Rui Gil CISUC, University of Coimbra Polo II – Universidade de Coimbra, 3030-290 Coimbra, Portugal +351-23979000 rgil@dei.uc.pt ... José Pedro Tavares CISUC, University of Coimbra Polo II – Universidade de Coimbra, 3030-290 Coimbra, Portugal +351-...