Articles de revista
http://hdl.handle.net/2117/3296
2016-04-30T13:40:00ZSerious games for screening pre-dementia conditions: from virtuality to reality? A pilot project
http://hdl.handle.net/2117/25078
Serious games for screening pre-dementia conditions: from virtuality to reality? A pilot project
Zuchella, Chiara; Sinforiani, Elena; Tassorelli, Cristina; Cavallini, Elena; Tost Pardell, Daniela; Grau Carrion, Sergi; Pazzi, Stefania; Puricelli, Stefano; Bernini, Sara; Bottiroli, Sara; Vecchi, Tomaso; Sandrini, Giorgio; Nappi, Giuseppe
Conventional cognitive assessment is based on a pencil-and-paper neuropsychological evaluation, which is time consuming, expensive and requires the involvement of several professionals. Information and communication technology could be exploited to allow the development of tools that are easy to use, reduce the amount of data processing, and provide controllable test conditions. Serious games (SGs) have the potential to be new and effective tools in the management and treatment of cognitive impairments in the elderly. Moreover, by adopting SGs in 3D virtual reality settings, cognitive functions might be evaluated using tasks that simulate daily activities, increasing the “ecological validity” of the assessment. In this commentary we report our experience in the creation of the Smart Aging platform, a 3D SG and virtual environment-based platform for the early identification and characterization of mild cognitive impairment.
2014-12-18T11:42:56ZZuchella, ChiaraSinforiani, ElenaTassorelli, CristinaCavallini, ElenaTost Pardell, DanielaGrau Carrion, SergiPazzi, StefaniaPuricelli, StefanoBernini, SaraBottiroli, SaraVecchi, TomasoSandrini, GiorgioNappi, GiuseppeConventional cognitive assessment is based on a pencil-and-paper neuropsychological evaluation, which is time consuming, expensive and requires the involvement of several professionals. Information and communication technology could be exploited to allow the development of tools that are easy to use, reduce the amount of data processing, and provide controllable test conditions. Serious games (SGs) have the potential to be new and effective tools in the management and treatment of cognitive impairments in the elderly. Moreover, by adopting SGs in 3D virtual reality settings, cognitive functions might be evaluated using tasks that simulate daily activities, increasing the “ecological validity” of the assessment. In this commentary we report our experience in the creation of the Smart Aging platform, a 3D SG and virtual environment-based platform for the early identification and characterization of mild cognitive impairment.Decomposition of geometric constraint graphs based on computing fundamental circuits. Correctness and complexity
http://hdl.handle.net/2117/24627
Decomposition of geometric constraint graphs based on computing fundamental circuits. Correctness and complexity
Joan Arinyo, Robert; Tarres Puertas, Marta Isabel; Vila Marta, Sebastià
In geometric constraint solving, Decomposition Recombination solvers (DR-solvers) refer to a general solving approach where the problem is divided into a set of sub-problems, each sub-problem is recursively divided until reaching basic problems which are solved by a dedicated equational solver. Then the solution to the starting problem is computed by merging the solutions to the sub-problems.; Triangle- or tree-decomposition is one of the most widely used approaches in the decomposition step in DR-solvers. It may be seen as decomposing a graph into three subgraphs such that subgraphs pairwise share one graph vertex. Shared vertices are called hinges. Then a merging step places the geometry in each sub-problem with respect to the other two.; In this work we report on a new algorithm to decompose biconnected geometric constraint graphs by searching for hinges in fundamental circuits of a specific planar embedding of the constraint graph. We prove that the algorithm is correct. (C) 2014 Elsevier Ltd. All rights reserved.
2014-11-10T10:06:18ZJoan Arinyo, RobertTarres Puertas, Marta IsabelVila Marta, SebastiàIn geometric constraint solving, Decomposition Recombination solvers (DR-solvers) refer to a general solving approach where the problem is divided into a set of sub-problems, each sub-problem is recursively divided until reaching basic problems which are solved by a dedicated equational solver. Then the solution to the starting problem is computed by merging the solutions to the sub-problems.; Triangle- or tree-decomposition is one of the most widely used approaches in the decomposition step in DR-solvers. It may be seen as decomposing a graph into three subgraphs such that subgraphs pairwise share one graph vertex. Shared vertices are called hinges. Then a merging step places the geometry in each sub-problem with respect to the other two.; In this work we report on a new algorithm to decompose biconnected geometric constraint graphs by searching for hinges in fundamental circuits of a specific planar embedding of the constraint graph. We prove that the algorithm is correct. (C) 2014 Elsevier Ltd. All rights reserved.The three-dimensional cube and scale cube skeleton
http://hdl.handle.net/2117/24572
The three-dimensional cube and scale cube skeleton
Martínez Bayona, Jonàs; Pla García, Núria; Vigo Anglada, Marc
The recently introduced cube and scale cube skeleton of Martínez et al. (Graph Models 75:189–207, 2013) are a new type of skeletal representations for polygons or polyhedra enclosed by axis-aligned edges or faces. In this paper, we present efficient algorithms to compute the three-dimensional cube and scale cube skeleton. In addition, we analyze the combinatorial complexity of the three-dimensional cube skeleton. We also introduce the three-dimensional interior cube skeleton, which is homotopically equivalent to the input shape. Finally, we experimentally evaluate the efficiency and robustness of all the presented algorithms and compare the obtained skeletons with other relevant skeletal representations.
2014-11-06T12:25:03ZMartínez Bayona, JonàsPla García, NúriaVigo Anglada, MarcThe recently introduced cube and scale cube skeleton of Martínez et al. (Graph Models 75:189–207, 2013) are a new type of skeletal representations for polygons or polyhedra enclosed by axis-aligned edges or faces. In this paper, we present efficient algorithms to compute the three-dimensional cube and scale cube skeleton. In addition, we analyze the combinatorial complexity of the three-dimensional cube skeleton. We also introduce the three-dimensional interior cube skeleton, which is homotopically equivalent to the input shape. Finally, we experimentally evaluate the efficiency and robustness of all the presented algorithms and compare the obtained skeletons with other relevant skeletal representations.First-person locomotion in 3D virtual environments: a usability analysis
http://hdl.handle.net/2117/24468
First-person locomotion in 3D virtual environments: a usability analysis
Moya Santos, Sergio; Grau Carrion, Sergi; Tost Pardell, Daniela
3D Virtual Environments (VE) are becoming popular as a tool for cognitive, functional and psychological assessment. Navigation in these environments is recognized as one of the most difficult activities in 3D Virtual Environments (VE). Users unfamiliar to 3D games, specially elder persons, get puzzled when they try to virtually move an avatar through these environments. Their inability to navigate prevents them from concentrating in the task and even to finish it. In this paper, we analyze the influence of different factors in locomotion control. We investigate the impact of having the cursor fixed at the camera center or leaving it free inside the current view. We also analyze the influence of the pitch angle on the camera control. In addition, we have designed an automatic locomotion system that we compare to user-controlled locomotion. We describe a virtual scenario and a test task that we have implemented to evaluate these different methods with users of diverse profiles.
2014-10-24T12:11:14ZMoya Santos, SergioGrau Carrion, SergiTost Pardell, Daniela3D Virtual Environments (VE) are becoming popular as a tool for cognitive, functional and psychological assessment. Navigation in these environments is recognized as one of the most difficult activities in 3D Virtual Environments (VE). Users unfamiliar to 3D games, specially elder persons, get puzzled when they try to virtually move an avatar through these environments. Their inability to navigate prevents them from concentrating in the task and even to finish it. In this paper, we analyze the influence of different factors in locomotion control. We investigate the impact of having the cursor fixed at the camera center or leaving it free inside the current view. We also analyze the influence of the pitch angle on the camera control. In addition, we have designed an automatic locomotion system that we compare to user-controlled locomotion. We describe a virtual scenario and a test task that we have implemented to evaluate these different methods with users of diverse profiles.A new lossless orthogonal simplification method for 3D objects based on bounding structures
http://hdl.handle.net/2117/23557
A new lossless orthogonal simplification method for 3D objects based on bounding structures
Cruz Matías, Irving Alberto; Ayala Vallespí, M. Dolors
This paper presents a new approach to simplify 3D binary images and general orthogonal pseudo-polyhedra (OPP). The method is incremental and produces a level-of-detail sequence of OPP, where any object of this sequence bounds the previous objects and, therefore, is a bounding orthogonal approximation of them. The sequence finishes with the axis-aligned bounding box. OPP are encoded using the Extreme Vertices Model, a complete model that stores a subset of their vertices and performs fast Boolean operations. Simplification is achieved by using a new strategy, which relies on the application of 2D Boolean operations. We also present a technique, based on model continuity, for better shape preservation. Finally, we present a data structure to encode in a progressive and lossless way the generated sequence. Tests with several datasets show that the proposed method produces smaller storage sizes and good quality approximations compared with other methods that also produce bounding objects.
2014-07-18T09:31:36ZCruz Matías, Irving AlbertoAyala Vallespí, M. DolorsThis paper presents a new approach to simplify 3D binary images and general orthogonal pseudo-polyhedra (OPP). The method is incremental and produces a level-of-detail sequence of OPP, where any object of this sequence bounds the previous objects and, therefore, is a bounding orthogonal approximation of them. The sequence finishes with the axis-aligned bounding box. OPP are encoded using the Extreme Vertices Model, a complete model that stores a subset of their vertices and performs fast Boolean operations. Simplification is achieved by using a new strategy, which relies on the application of 2D Boolean operations. We also present a technique, based on model continuity, for better shape preservation. Finally, we present a data structure to encode in a progressive and lossless way the generated sequence. Tests with several datasets show that the proposed method produces smaller storage sizes and good quality approximations compared with other methods that also produce bounding objects.Juegos digitales en el aula: un caso de estudio
http://hdl.handle.net/2117/22346
Juegos digitales en el aula: un caso de estudio
Eguía Gómez, Jose Luis; Solano Albajés, Lluís; Contreras Espinoza, Ruth Sofia
Durante el año 2011 se diseño, implementó y estudió un juego digital que muestra la vida de un científico Catalán: El paleontólogo Miquel Crusafont. El juego fue creado como un recurso para el aprendizaje cognitivo y posteriormente fue utilizado en aulas de primaria con el fin de obtener la visión de los profesores involucrados. Como método de recolección de datos se ha utilizado la observación, la entrevista en profundidad y el grupo focal. El objetivo principal de este estudio se centra en reunir la visión de profesores de primaria, al hacer uso de juegos en el aula. Las conclusiones nos muestran las percepciones que los miembros del grupo de estudio tiene sobre el uso de juegos digitales.
2014-03-21T19:47:08ZEguía Gómez, Jose LuisSolano Albajés, LluísContreras Espinoza, Ruth SofiaDurante el año 2011 se diseño, implementó y estudió un juego digital que muestra la vida de un científico Catalán: El paleontólogo Miquel Crusafont. El juego fue creado como un recurso para el aprendizaje cognitivo y posteriormente fue utilizado en aulas de primaria con el fin de obtener la visión de los profesores involucrados. Como método de recolección de datos se ha utilizado la observación, la entrevista en profundidad y el grupo focal. El objetivo principal de este estudio se centra en reunir la visión de profesores de primaria, al hacer uso de juegos en el aula. Las conclusiones nos muestran las percepciones que los miembros del grupo de estudio tiene sobre el uso de juegos digitales.Jeux qu'on prend au sérieux- Pour l'intercompréhension des langues étrangères
http://hdl.handle.net/2117/20478
Jeux qu'on prend au sérieux- Pour l'intercompréhension des langues étrangères
Tost Planet, Manuel; Tost Pardell, Daniela
L’insertion curriculaire de l’intercompréhension en contexte scolaire dépend en grande mesure de l’offre qu’on pourra faire aux systèmes éducatifs de matériaux motivants et pas trop dérangeants pour l’institution. Dans le texte qui suit, après avoir contextualisé brièvement cette problématique, nous présentons ce qu’on appelle les «jeux sérieux» et la littérature, surtout anglo-saxonne, qu’ils ont suscitée; nous les articulons, ensuite, avec la pratique de l’IC, avant d’exposer, schématiquement, une application, encore en chantier, de cette thématique.
2013-10-27T13:33:48ZTost Planet, ManuelTost Pardell, DanielaL’insertion curriculaire de l’intercompréhension en contexte scolaire dépend en grande mesure de l’offre qu’on pourra faire aux systèmes éducatifs de matériaux motivants et pas trop dérangeants pour l’institution. Dans le texte qui suit, après avoir contextualisé brièvement cette problématique, nous présentons ce qu’on appelle les «jeux sérieux» et la littérature, surtout anglo-saxonne, qu’ils ont suscitée; nous les articulons, ensuite, avec la pratique de l’IC, avant d’exposer, schématiquement, une application, encore en chantier, de cette thématique.Region-based illustrative visualization of multimodal datasets
http://hdl.handle.net/2117/20476
Region-based illustrative visualization of multimodal datasets
Abellán Moreno, Pascual; Tost Pardell, Daniela; Grau Carrion, Sergi; Puig Puig, Anna
We present as novel method for the exploration of multiple overlapping volumes that provides flexibility to merge data in different ways in different regions. In each region, either one of the modalities is rendered alone or the fusion of two modalities is shown. In the regions where data is fused, the relative weights of
each modality are defined with a 2D transfer function depending on the voxel’s pair of property values. The regions can be defined interactively by painting on the volume. Alternatively, when one of the modalities
has been pre-classified, a graph representation of the dataset is constructed, and regions can be defined
as sets of voxels fulfilling a specific combination of classification criteria. In both cases, a different fusion and shading function can be defined for each region. In this way, illustrative images of the dataset can be easily generated applying effects of cutting away, ghosting and modality enhancement.
2013-10-27T12:57:31ZAbellán Moreno, PascualTost Pardell, DanielaGrau Carrion, SergiPuig Puig, AnnaWe present as novel method for the exploration of multiple overlapping volumes that provides flexibility to merge data in different ways in different regions. In each region, either one of the modalities is rendered alone or the fusion of two modalities is shown. In the regions where data is fused, the relative weights of
each modality are defined with a 2D transfer function depending on the voxel’s pair of property values. The regions can be defined interactively by painting on the volume. Alternatively, when one of the modalities
has been pre-classified, a graph representation of the dataset is constructed, and regions can be defined
as sets of voxels fulfilling a specific combination of classification criteria. In both cases, a different fusion and shading function can be defined for each region. In this way, illustrative images of the dataset can be easily generated applying effects of cutting away, ghosting and modality enhancement.The wise cursor: assisted selection in 3D serious games
http://hdl.handle.net/2117/20333
The wise cursor: assisted selection in 3D serious games
Moya Santos, Sergio; Grau Carrion, Sergi; Tost Pardell, Daniela
In recent years, the evolution of 3D graphics hardware
and software has lead to a growing interest for serious
games in three-dimensional virtual environments for learning,
training, and rehabilitation. Many of these games are
based on a first-person-shooter paradigm in which users navigate
through the environment, select, and manipulate virtual
objects. The target users of these applications are not
necessarily usual gamers, and they often have difficulties in
navigating and interacting in the 3D environment.
This paper proposes the wise cursor, a new method for
selection that improves the usability and accessibility of
mouse-driven serious games in 3D environments. At each
user click, the proposed method computes a list of objects
candidates to be selected and their probability of being the
desired one. Depending on the uncertainty of the probability
distribution, either one object is selected or a mechanism to
clarify the selection is proposed. In the former case, if the
selected object is within the user avatar’s scope, the action
associated to it is realized, otherwise the application automatically
navigates toward it. In this way, selection and navigation
are eased. The empirical results of the usability tests
show that this technique is fast, practical, and that it requires
little user’s skills. Thus, it can make serious games usable
for a wider range of users who can concentrate on the training
objectives without technological barriers.
2013-10-08T12:49:57ZMoya Santos, SergioGrau Carrion, SergiTost Pardell, DanielaIn recent years, the evolution of 3D graphics hardware
and software has lead to a growing interest for serious
games in three-dimensional virtual environments for learning,
training, and rehabilitation. Many of these games are
based on a first-person-shooter paradigm in which users navigate
through the environment, select, and manipulate virtual
objects. The target users of these applications are not
necessarily usual gamers, and they often have difficulties in
navigating and interacting in the 3D environment.
This paper proposes the wise cursor, a new method for
selection that improves the usability and accessibility of
mouse-driven serious games in 3D environments. At each
user click, the proposed method computes a list of objects
candidates to be selected and their probability of being the
desired one. Depending on the uncertainty of the probability
distribution, either one object is selected or a mechanism to
clarify the selection is proposed. In the former case, if the
selected object is within the user avatar’s scope, the action
associated to it is realized, otherwise the application automatically
navigates toward it. In this way, selection and navigation
are eased. The empirical results of the usability tests
show that this technique is fast, practical, and that it requires
little user’s skills. Thus, it can make serious games usable
for a wider range of users who can concentrate on the training
objectives without technological barriers.The Reachability problem in constructive geometric constraint solving based dynamic geometry
http://hdl.handle.net/2117/19397
The Reachability problem in constructive geometric constraint solving based dynamic geometry
Hidalgo Garcia, Marta; Joan Arinyo, Robert
An important issue in dynamic geometry is the reachability problem that
asks whether there is a continuous path that, from a given starting geometric
configuration, continuously leads to an ending configuration. In this work we report
on a technique to compute a continuous evaluation path, if one exists, that solves
the reachability problem for geometric constructions with one variant parameter.
The technique is developed in the framework of a constructive geometric constraintbased
dynamic geometry system, uses the A∗ algorithm and minimizes the variant
parameter arc length.
2013-05-27T08:49:41ZHidalgo Garcia, MartaJoan Arinyo, RobertAn important issue in dynamic geometry is the reachability problem that
asks whether there is a continuous path that, from a given starting geometric
configuration, continuously leads to an ending configuration. In this work we report
on a technique to compute a continuous evaluation path, if one exists, that solves
the reachability problem for geometric constructions with one variant parameter.
The technique is developed in the framework of a constructive geometric constraintbased
dynamic geometry system, uses the A∗ algorithm and minimizes the variant
parameter arc length.