GIE - Grup d'Informàtica en l'Enginyeria
http://hdl.handle.net/2117/3295
2017-10-18T18:52:16ZCompact union of disjoint boxes: An efficient decomposition model for binary volumes
http://hdl.handle.net/2117/107808
Compact union of disjoint boxes: An efficient decomposition model for binary volumes
Cruz Matías, Irving; Ayala Vallespí, M. Dolors
This paper presents in detail the CompactUnion of Disjoint Boxes (CUDB), a decomposition modelfor binary volumes that has been recently but brieflyintroduced. This model is an improved version of aprevious model called Ordered Union of Disjoint Boxes(OUDB). We show here, several desirable features thatthis model has versus OUDB, such as less unitary basicelements (boxes) and thus, a better efficiency in someneighborhood operations. We present algorithms forconversion to and from other models, and for basiccomputations as area (2D) or volume (3D). We alsopresent an efficient algorithm for connected-componentlabeling (CCL) that does not follow the classical two-passstrategy. Finally we present an algorithm for collision (oradjacency) detection in static environments. We test theefficiency of CUDB versus existing models with severaldatasets.
2017-09-20T09:39:52ZCruz Matías, IrvingAyala Vallespí, M. DolorsThis paper presents in detail the CompactUnion of Disjoint Boxes (CUDB), a decomposition modelfor binary volumes that has been recently but brieflyintroduced. This model is an improved version of aprevious model called Ordered Union of Disjoint Boxes(OUDB). We show here, several desirable features thatthis model has versus OUDB, such as less unitary basicelements (boxes) and thus, a better efficiency in someneighborhood operations. We present algorithms forconversion to and from other models, and for basiccomputations as area (2D) or volume (3D). We alsopresent an efficient algorithm for connected-componentlabeling (CCL) that does not follow the classical two-passstrategy. Finally we present an algorithm for collision (oradjacency) detection in static environments. We test theefficiency of CUDB versus existing models with severaldatasets.On the characterization of weighted simple games
http://hdl.handle.net/2117/107644
On the characterization of weighted simple games
Freixas Bosch, Josep; Freixas Boleda, Marc; Kurz, Sascha
This paper has a twofold scope. The first one is to clarify and put in evidence the isomorphic character of two theories developed in quite different fields: on one side, threshold logic, on the other side, simple games. One of the main purposes in both theories is to determine when a simple game is representable as a weighted game, which allows a very compact and easily comprehensible representation. Deep results were found in threshold logic in the sixties and seventies for this problem. However, game theory has taken the lead and some new results have been obtained for the problem in the past two decades. The second and main goal of this paper is to provide some new results on this problem and propose several open questions and conjectures for future research. The results we obtain depend on two significant parameters of the game: the number of types of equivalent players and the number of types of shift-minimal winning coalitions.
2017-09-14T17:51:00ZFreixas Bosch, JosepFreixas Boleda, MarcKurz, SaschaThis paper has a twofold scope. The first one is to clarify and put in evidence the isomorphic character of two theories developed in quite different fields: on one side, threshold logic, on the other side, simple games. One of the main purposes in both theories is to determine when a simple game is representable as a weighted game, which allows a very compact and easily comprehensible representation. Deep results were found in threshold logic in the sixties and seventies for this problem. However, game theory has taken the lead and some new results have been obtained for the problem in the past two decades. The second and main goal of this paper is to provide some new results on this problem and propose several open questions and conjectures for future research. The results we obtain depend on two significant parameters of the game: the number of types of equivalent players and the number of types of shift-minimal winning coalitions.Investigación-acción como metodología para el diseño de un serious game
http://hdl.handle.net/2117/104534
Investigación-acción como metodología para el diseño de un serious game
Contreras Espinoza, Ruth Sofia; Eguía Gómez, Jose Luis; Solano Albajés, Lluís
Se ha producido un importante desarrollo en la investigación relacionada con los juegos educativos y, en especial, con los serious games y el aprendizaje basado en juegos digitales durante la última década. De particular interés son las posibilidades que proporcionan este tipo de juegos para involucrar a los estudiantes en la experiencia de aprendizaje. Los avances recientes incluyen desde desarrollos teóricos hasta la creación de juegos digitales para una amplia gama de planes de estudios o la aparición de entornos de aprendizaje basados en juegos tanto para la educación formal como para la formación de personas. Pero todavía hacen falta principios y propuestas para la investigación y el diseño de serious games, experimentos y metodologías basadas en el diseño de juegos. En este artículo presentamos una experiencia llevada a cabo por un grupo multidisciplinario de investigadores en colaboración con profesores de primaria de la ciudad de Barcelona, España, para desarrollar un juego digital que permite trabajar competencias de educación orientadas a estudiantes de primaria. Hemos diseñado un juego digital utilizando un proceso de cocreación con base en la metodología investigación-acción. El juego llamado Ferran Alsina se creó como un facilitador de una nueva metodología de enseñanza y se centra en trabajar con competencias básicas, metodológicas y específicas para niños de primaria, con edades entre los 8 y 11 años de edad.
2017-05-17T08:24:38ZContreras Espinoza, Ruth SofiaEguía Gómez, Jose LuisSolano Albajés, LluísSe ha producido un importante desarrollo en la investigación relacionada con los juegos educativos y, en especial, con los serious games y el aprendizaje basado en juegos digitales durante la última década. De particular interés son las posibilidades que proporcionan este tipo de juegos para involucrar a los estudiantes en la experiencia de aprendizaje. Los avances recientes incluyen desde desarrollos teóricos hasta la creación de juegos digitales para una amplia gama de planes de estudios o la aparición de entornos de aprendizaje basados en juegos tanto para la educación formal como para la formación de personas. Pero todavía hacen falta principios y propuestas para la investigación y el diseño de serious games, experimentos y metodologías basadas en el diseño de juegos. En este artículo presentamos una experiencia llevada a cabo por un grupo multidisciplinario de investigadores en colaboración con profesores de primaria de la ciudad de Barcelona, España, para desarrollar un juego digital que permite trabajar competencias de educación orientadas a estudiantes de primaria. Hemos diseñado un juego digital utilizando un proceso de cocreación con base en la metodología investigación-acción. El juego llamado Ferran Alsina se creó como un facilitador de una nueva metodología de enseñanza y se centra en trabajar con competencias básicas, metodológicas y específicas para niños de primaria, con edades entre los 8 y 11 años de edad.Can 3D gamified simulations be valid vocational training tools for persons with intellectual disability? A pilot based on a real-life situation
http://hdl.handle.net/2117/102971
Can 3D gamified simulations be valid vocational training tools for persons with intellectual disability? A pilot based on a real-life situation
von Barnekow, Ariel; Bonet Codina, Núria; Tost Pardell, Daniela
Objective: To investigate if 3D gamified simulations can be valid vocational training tools for persons with intellectual disability. Methods: A 3D gamified simulation composed by a set of training tasks for cleaning in hostelry was developed in collaboration with professionals of a real hostel and pedagogues of a special needs school. The learning objectives focus on the acquisition of vocabulary skills, work procedures, social abilities and risk prevention. Several accessibility features were developed to make the tasks easy to do from a technological point-of-view. A pilot experiment was conducted to test the pedagogical efficacy of this tool on intellectually disabled workers and students. Results: User scores in the gamified simulation follow a curve of increasing progression. When confronted with reality, they recognized the scenario and tried to reproduce what they had learned in the simulation. Finally, they were interested in the tool, they showed a strong feeling of immersion and engagement, and they reported having fun. Conclusions: On the basis of this experiment we believe that 3D gamified simulations can be efficient tools to train social and professional skills of persons with intellectual disabilities contributing thus to foster their social inclusion through work.
2017-03-28T13:31:23Zvon Barnekow, ArielBonet Codina, NúriaTost Pardell, DanielaObjective: To investigate if 3D gamified simulations can be valid vocational training tools for persons with intellectual disability. Methods: A 3D gamified simulation composed by a set of training tasks for cleaning in hostelry was developed in collaboration with professionals of a real hostel and pedagogues of a special needs school. The learning objectives focus on the acquisition of vocabulary skills, work procedures, social abilities and risk prevention. Several accessibility features were developed to make the tasks easy to do from a technological point-of-view. A pilot experiment was conducted to test the pedagogical efficacy of this tool on intellectually disabled workers and students. Results: User scores in the gamified simulation follow a curve of increasing progression. When confronted with reality, they recognized the scenario and tried to reproduce what they had learned in the simulation. Finally, they were interested in the tool, they showed a strong feeling of immersion and engagement, and they reported having fun. Conclusions: On the basis of this experiment we believe that 3D gamified simulations can be efficient tools to train social and professional skills of persons with intellectual disabilities contributing thus to foster their social inclusion through work.SKETCH'NDO: A framework for the creation of task-based serious games
http://hdl.handle.net/2117/102805
SKETCH'NDO: A framework for the creation of task-based serious games
Moya Santos, Sergi; Tost Pardell, Daniela; von Barnekow, Ariel; Félix, Eloy
We present SKETCH'NDO, a framework for the interactive design and creation of single-user task-based serious games in 3D virtual environments. The games are dimensionally congruent: inherently 2D tasks such as reading and writing are done in 2D, while manipulation tasks are 3D. The architecture of the system allows educators to design the tasks with a graphical editor that creates the game automatically. This editor does not require gaming expertise. It only needs educators to specify the correct ways of doing the task, without having to consider all possible erroneous learner's decisions. SKETCH'NDO provides a complete mechanism of monitoring and evaluation of the learner's performance that allows a precise assessment of the learning process. It offers a gradation of levels of assistance that can be fixed by educators or automatically adjusted to the trainee's skills. This way, the same task can be trained from a strictly conductist strategy to a fully constructivist one.
2017-03-22T16:08:44ZMoya Santos, SergiTost Pardell, Danielavon Barnekow, ArielFélix, EloyWe present SKETCH'NDO, a framework for the interactive design and creation of single-user task-based serious games in 3D virtual environments. The games are dimensionally congruent: inherently 2D tasks such as reading and writing are done in 2D, while manipulation tasks are 3D. The architecture of the system allows educators to design the tasks with a graphical editor that creates the game automatically. This editor does not require gaming expertise. It only needs educators to specify the correct ways of doing the task, without having to consider all possible erroneous learner's decisions. SKETCH'NDO provides a complete mechanism of monitoring and evaluation of the learner's performance that allows a precise assessment of the learning process. It offers a gradation of levels of assistance that can be fixed by educators or automatically adjusted to the trainee's skills. This way, the same task can be trained from a strictly conductist strategy to a fully constructivist one.A Henneberg-based algorithm for generating tree-decomposable minimally rigid graphs
http://hdl.handle.net/2117/102162
A Henneberg-based algorithm for generating tree-decomposable minimally rigid graphs
Hidalgo, Marta R.; Joan Arinyo, Robert
In this work we describe an algorithm to generate tree-decomposable minimally rigid graphs on a given set of vertices V . The main idea is based on the well-known fact that all minimally rigid graphs, also known as Laman graphs, can be generated via Henneberg sequences. Given that not each minimally rigid graph is tree-decomposable, we identify a set of conditions on the way Henneberg steps are applied so that the resulting graph is tree-decomposable. We show that the worst case running time of the algorithm is O(|V|3).
2017-03-08T18:57:16ZHidalgo, Marta R.Joan Arinyo, RobertIn this work we describe an algorithm to generate tree-decomposable minimally rigid graphs on a given set of vertices V . The main idea is based on the well-known fact that all minimally rigid graphs, also known as Laman graphs, can be generated via Henneberg sequences. Given that not each minimally rigid graph is tree-decomposable, we identify a set of conditions on the way Henneberg steps are applied so that the resulting graph is tree-decomposable. We show that the worst case running time of the algorithm is O(|V|3).Ordering triangles in triangulated terrains over regular grids
http://hdl.handle.net/2117/102161
Ordering triangles in triangulated terrains over regular grids
Joan Arinyo, Robert; Alonso Alonso, Jesús
In this work we report on a set of rules to visit triangles in triangulated height fields defined over regular grids in a back-to- front order with respect to an arbitrary viewpoint. With the viewpoint, we associate an axis-alligned local reference framework. Projections on the XY plane of the local axis and the bisector of the first and third quadrants define six sectors. Specific visiting rules for collections of triangles that project on each sector are then defined. The experiments conducted show that the implementation of a simple algorithm based on the set of visiting rules defined allows real time interaction when the viewing position moves along an arbitrary 3D path.
2017-03-08T18:48:31ZJoan Arinyo, RobertAlonso Alonso, JesúsIn this work we report on a set of rules to visit triangles in triangulated height fields defined over regular grids in a back-to- front order with respect to an arbitrary viewpoint. With the viewpoint, we associate an axis-alligned local reference framework. Projections on the XY plane of the local axis and the bisector of the first and third quadrants define six sectors. Specific visiting rules for collections of triangles that project on each sector are then defined. The experiments conducted show that the implementation of a simple algorithm based on the set of visiting rules defined allows real time interaction when the viewing position moves along an arbitrary 3D path.h-graphs: A new representation for tree decompositions of graphs
http://hdl.handle.net/2117/99483
h-graphs: A new representation for tree decompositions of graphs
Hidalgo Garcia, Marta; Joan Arinyo, Robert
In geometric constraint solving, well constrained geometric problems can be abstracted as Laman graphs. If the graph is tree decomposable, the constraint-based geometric problem can be solved by a Decomposition-Recombination planner based solver. In general decomposition and recombination steps can be completed only when other steps have already been completed. This fact naturally defines a hierarchy in the decomposition-recombination steps that traditional tree decomposition representations do not capture explicitly. In this work we introduce h-graphs, a new representation for decompositions of tree decomposable Laman graphs, which captures dependence relations between different tree decomposition steps. We show how h-graphs help in efficiently computing parameter ranges for which solution instances to well constrained, tree decomposable geometric constraint problems with one degree of freedom can actually be constructed.
2017-01-17T13:41:49ZHidalgo Garcia, MartaJoan Arinyo, RobertIn geometric constraint solving, well constrained geometric problems can be abstracted as Laman graphs. If the graph is tree decomposable, the constraint-based geometric problem can be solved by a Decomposition-Recombination planner based solver. In general decomposition and recombination steps can be completed only when other steps have already been completed. This fact naturally defines a hierarchy in the decomposition-recombination steps that traditional tree decomposition representations do not capture explicitly. In this work we introduce h-graphs, a new representation for decompositions of tree decomposable Laman graphs, which captures dependence relations between different tree decomposition steps. We show how h-graphs help in efficiently computing parameter ranges for which solution instances to well constrained, tree decomposable geometric constraint problems with one degree of freedom can actually be constructed.On tree decomposability of Henneberg graphs
http://hdl.handle.net/2117/99452
On tree decomposability of Henneberg graphs
Hidalgo, Marta R.; Joan Arinyo, Robert
In this work we describe an algorithm that generates well constrained geometric constraint graphs which are solvable by the tree-decomposition constructive technique. The algorithm is based on Henneberg constructions and would be of help in transforming underconstrained problems into well constrained problems as well as in exploring alternative constructions over a given set of geometric elements.
2017-01-17T12:40:22ZHidalgo, Marta R.Joan Arinyo, RobertIn this work we describe an algorithm that generates well constrained geometric constraint graphs which are solvable by the tree-decomposition constructive technique. The algorithm is based on Henneberg constructions and would be of help in transforming underconstrained problems into well constrained problems as well as in exploring alternative constructions over a given set of geometric elements.Orientation, sphericity and roundness evaluation of particles using alternative 3D representations
http://hdl.handle.net/2117/99446
Orientation, sphericity and roundness evaluation of particles using alternative 3D representations
Cruz Matías, Irving; Ayala Vallespí, M. Dolors
Sphericity and roundness indices have been used mainly in geology to analyze the shape of particles. In this paper, geometric methods are proposed as an alternative to evaluate the orientation, sphericity and roundness indices of 3D objects. In contrast to previous works based on digital images, which use the voxel model, we represent the particles with the Extreme Vertices Model, a very concise representation for binary volumes. We define the orientation with three mutually orthogonal unit vectors. Then, some sphericity indices based on length measurement of the three representative axes of the particle can be computed. In addition, we propose a ray-casting-like approach to evaluate a 3D roundness index. This method provides roundness measurements that are highly correlated with those provided by the Krumbein's chart and other previous approach. Finally, as an example we apply the presented methods to analyze the sphericity and roundness of a real silica nano dataset.
2017-01-17T12:25:33ZCruz Matías, IrvingAyala Vallespí, M. DolorsSphericity and roundness indices have been used mainly in geology to analyze the shape of particles. In this paper, geometric methods are proposed as an alternative to evaluate the orientation, sphericity and roundness indices of 3D objects. In contrast to previous works based on digital images, which use the voxel model, we represent the particles with the Extreme Vertices Model, a very concise representation for binary volumes. We define the orientation with three mutually orthogonal unit vectors. Then, some sphericity indices based on length measurement of the three representative axes of the particle can be computed. In addition, we propose a ray-casting-like approach to evaluate a 3D roundness index. This method provides roundness measurements that are highly correlated with those provided by the Krumbein's chart and other previous approach. Finally, as an example we apply the presented methods to analyze the sphericity and roundness of a real silica nano dataset.