Reports de recerca
http://hdl.handle.net/2117/3973
Sun, 22 Jan 2017 04:06:23 GMT2017-01-22T04:06:23ZA multi-projector CAVE system with commodity hardware and gesture-based interaction
http://hdl.handle.net/2117/99668
A multi-projector CAVE system with commodity hardware and gesture-based interaction
Andújar Gran, Carlos Antonio; Brunet Crosa, Pere; Vinacua Pla, Álvaro; Vico Moya, Miguel Ángel; Díaz García, Jesús
Spatially-immersive systems such as CAVEs provide users with surrounding worlds by projecting 3D models on multiple screens around the viewer. Compared to alternative immersive systems such as HMDs, CAVE systems are a powerful tool for collaborative inspection of virtual environments due to better use of peripheral vision, less sensitivity to tracking errors, and higher communication possibilities among users. Unfortunately, traditional CAVE setups require sophisticated equipment including stereo-ready projectors and tracking systems with high acquisition and maintenance costs. In this paper we present the design and construction of a passive-stereo, four-wall CAVE system based on commodity hardware. Our system works with any mix of a wide range of projector models that can be replaced independently at any time, and achieves high resolution and brightness at a minimum cost. The key ingredients of our CAVE are a self-calibration approach that guarantees continuity across the screen, as well as a gesture-based interaction approach based on a clever
combination of skeletal data from multiple Kinect sensors.
Thu, 19 Jan 2017 11:55:25 GMThttp://hdl.handle.net/2117/996682017-01-19T11:55:25ZAndújar Gran, Carlos AntonioBrunet Crosa, PereVinacua Pla, ÁlvaroVico Moya, Miguel ÁngelDíaz García, JesúsSpatially-immersive systems such as CAVEs provide users with surrounding worlds by projecting 3D models on multiple screens around the viewer. Compared to alternative immersive systems such as HMDs, CAVE systems are a powerful tool for collaborative inspection of virtual environments due to better use of peripheral vision, less sensitivity to tracking errors, and higher communication possibilities among users. Unfortunately, traditional CAVE setups require sophisticated equipment including stereo-ready projectors and tracking systems with high acquisition and maintenance costs. In this paper we present the design and construction of a passive-stereo, four-wall CAVE system based on commodity hardware. Our system works with any mix of a wide range of projector models that can be replaced independently at any time, and achieves high resolution and brightness at a minimum cost. The key ingredients of our CAVE are a self-calibration approach that guarantees continuity across the screen, as well as a gesture-based interaction approach based on a clever
combination of skeletal data from multiple Kinect sensors.Projecte Inspira'ns: detecció d'idees relacionades
http://hdl.handle.net/2117/99488
Projecte Inspira'ns: detecció d'idees relacionades
Vigo, M.
El projecte Inspira'ns compta amb un sistema online per a la recollida de suggeriments i comentaris (Idea) d'usuaris. Aquests comentaris es classifiquen per categories (Aplicacions mòbils, Banca mòbil, Banca per Internet, Caixers i Targetes), i pels temes que tracten (el tema és lliure, generalment es tracta de peticions de millora d'un servei o problemes detectats amb algun producte o servei, entre d'altres). Sovint els usuaris es refereixen a una mateixa Idea, és a dir, es reben suggeriments i comentaris repetits. Actualment, la classificació d'aquestes idees es duu a terme de forma manual. L'objectiu d'aquest projecte és desenvolupar una metodologia que permeti detectar que una nova Idea és similar a una Idea anterior rebuda. És a dir, donat un conjunt D d'idees, determinar si una nova Idea d està relacionada (és similar) amb alguna de les idees del conjunt D.
Tue, 17 Jan 2017 14:03:35 GMThttp://hdl.handle.net/2117/994882017-01-17T14:03:35ZVigo, M.El projecte Inspira'ns compta amb un sistema online per a la recollida de suggeriments i comentaris (Idea) d'usuaris. Aquests comentaris es classifiquen per categories (Aplicacions mòbils, Banca mòbil, Banca per Internet, Caixers i Targetes), i pels temes que tracten (el tema és lliure, generalment es tracta de peticions de millora d'un servei o problemes detectats amb algun producte o servei, entre d'altres). Sovint els usuaris es refereixen a una mateixa Idea, és a dir, es reben suggeriments i comentaris repetits. Actualment, la classificació d'aquestes idees es duu a terme de forma manual. L'objectiu d'aquest projecte és desenvolupar una metodologia que permeti detectar que una nova Idea és similar a una Idea anterior rebuda. És a dir, donat un conjunt D d'idees, determinar si una nova Idea d està relacionada (és similar) amb alguna de les idees del conjunt D.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.
Tue, 17 Jan 2017 13:41:49 GMThttp://hdl.handle.net/2117/994832017-01-17T13:41:49ZHidalgo 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.Firefighting as a Game
http://hdl.handle.net/2117/99479
Firefighting as a Game
Álvarez Faura, M. del Carme; Blesa Aguilera, Maria Josep; Molter, Hendrik
The Firefighter Problem was proposed in 1995 [16] as a deterministic discrete-time model for the spread (and containment) of a fire. Its applications reach from real fires to the spreading of deseases and the containment of floods. Furthermore, it can be used to model the spread of computer viruses or viral marketing in communication networks. In this work, we study the problem from a game-theorical perspective. Such a context seems very appropriate when applied to large networks, where entities may act and make decisions based on their own interests, without global coordination. We model the Firefighter Problem as a strategic game where there is one player for each time step who decides where to place the firefighters. We show that the Price of Anarchy is linear in the general case, but at most 2 for trees. We prove that the quality of the equilibria improves when allowing coalitional cooperation among players. In general, we have that the Price of Anarchy is in O( n / k ) where k is the coalition size. Furthermore, we show that there are topologies which have a constant Price of Anarchy even when constant sized coalitions are considered.
Tue, 17 Jan 2017 13:25:59 GMThttp://hdl.handle.net/2117/994792017-01-17T13:25:59ZÁlvarez Faura, M. del CarmeBlesa Aguilera, Maria JosepMolter, HendrikThe Firefighter Problem was proposed in 1995 [16] as a deterministic discrete-time model for the spread (and containment) of a fire. Its applications reach from real fires to the spreading of deseases and the containment of floods. Furthermore, it can be used to model the spread of computer viruses or viral marketing in communication networks. In this work, we study the problem from a game-theorical perspective. Such a context seems very appropriate when applied to large networks, where entities may act and make decisions based on their own interests, without global coordination. We model the Firefighter Problem as a strategic game where there is one player for each time step who decides where to place the firefighters. We show that the Price of Anarchy is linear in the general case, but at most 2 for trees. We prove that the quality of the equilibria improves when allowing coalitional cooperation among players. In general, we have that the Price of Anarchy is in O( n / k ) where k is the coalition size. Furthermore, we show that there are topologies which have a constant Price of Anarchy even when constant sized coalitions are considered.A graph-semantics of business configurations
http://hdl.handle.net/2117/99474
A graph-semantics of business configurations
Fiadeiro, José Luiz; Mylonakis Pascual, Nicolás; Orejas Valdés, Fernando
In this paper we give graph-semantics to a fundamental part of the semantics of the service modeling language SRML. To achieve this goal we develop a new graph transformation system for what we call 2-level symbolic graphs. These kind of graphs extend symbolic graphs with a simple 2-level hierarchy that can be generalized to arbitrary hierarchies. We formalize the semantics using this new graph transformation system using a simple example of a trip booking agent.
Tue, 17 Jan 2017 13:16:27 GMThttp://hdl.handle.net/2117/994742017-01-17T13:16:27ZFiadeiro, José LuizMylonakis Pascual, NicolásOrejas Valdés, FernandoIn this paper we give graph-semantics to a fundamental part of the semantics of the service modeling language SRML. To achieve this goal we develop a new graph transformation system for what we call 2-level symbolic graphs. These kind of graphs extend symbolic graphs with a simple 2-level hierarchy that can be generalized to arbitrary hierarchies. We formalize the semantics using this new graph transformation system using a simple example of a trip booking agent.NiMo syntax: part 1
http://hdl.handle.net/2117/99459
NiMo syntax: part 1
Clérici Martínez, Silvia Inés; Prestigiacomo, Guillermo; Zoltan, Cristina
Many formalisms for the specification for concurrent and distributed systems have emerged. In particular considering boxes and strings approaches. Examples are action calculi, rewriting logic and graph rewriting, bigraphs. The boxes and string metaphor is addressed with different levels of granularity. One of the approaches is to consider a process network as an hypergraph. Based in this general framework, we encode NiMo nets as a class of Annotated hypergraphs. This class is defined by giving the alphabet and the operations used to construct such programs. Therefore we treat only editing operations on labelled hypergraphs and afterwards how this editing operation affects the graph. Graph transformation (execution rules) is not covered here.
Tue, 17 Jan 2017 12:56:06 GMThttp://hdl.handle.net/2117/994592017-01-17T12:56:06ZClérici Martínez, Silvia InésPrestigiacomo, GuillermoZoltan, CristinaMany formalisms for the specification for concurrent and distributed systems have emerged. In particular considering boxes and strings approaches. Examples are action calculi, rewriting logic and graph rewriting, bigraphs. The boxes and string metaphor is addressed with different levels of granularity. One of the approaches is to consider a process network as an hypergraph. Based in this general framework, we encode NiMo nets as a class of Annotated hypergraphs. This class is defined by giving the alphabet and the operations used to construct such programs. Therefore we treat only editing operations on labelled hypergraphs and afterwards how this editing operation affects the graph. Graph transformation (execution rules) is not covered here.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.
Tue, 17 Jan 2017 12:40:22 GMThttp://hdl.handle.net/2117/994522017-01-17T12:40:22ZHidalgo, 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.Similarity networks for classification: a case study in the Horse Colic problem
http://hdl.handle.net/2117/99450
Similarity networks for classification: a case study in the Horse Colic problem
Belanche Muñoz, Luis Antonio; Hernández González, Jerónimo
This paper develops a two-layer neural network in which the neuron model computes a user-defined similarity function between inputs and weights. The neuron transfer function is formed by composition of an adapted logistic function with the mean of the partial input-weight similarities. The resulting neuron model is capable of dealing directly with variables of potentially different nature (continuous, fuzzy, ordinal, categorical). There is also provision for missing values. The network is trained using a two-stage procedure very similar to that used to train a radial basis function (RBF) neural network. The network is compared to two types of RBF networks in a non-trivial dataset: the Horse Colic problem, taken as a case study and analyzed in detail.
Tue, 17 Jan 2017 12:32:58 GMThttp://hdl.handle.net/2117/994502017-01-17T12:32:58ZBelanche Muñoz, Luis AntonioHernández González, JerónimoThis paper develops a two-layer neural network in which the neuron model computes a user-defined similarity function between inputs and weights. The neuron transfer function is formed by composition of an adapted logistic function with the mean of the partial input-weight similarities. The resulting neuron model is capable of dealing directly with variables of potentially different nature (continuous, fuzzy, ordinal, categorical). There is also provision for missing values. The network is trained using a two-stage procedure very similar to that used to train a radial basis function (RBF) neural network. The network is compared to two types of RBF networks in a non-trivial dataset: the Horse Colic problem, taken as a case study and analyzed in detail.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.
Tue, 17 Jan 2017 12:25:33 GMThttp://hdl.handle.net/2117/994462017-01-17T12:25:33ZCruz 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.Towards automatic construction of domain ontologies: Application to ISA88 and assessment
http://hdl.handle.net/2117/99442
Towards automatic construction of domain ontologies: Application to ISA88 and assessment
Farreres de la Morena, Xavier; Graells Sobré, Moisès; Rodríguez Hontoria, Horacio; Espuña Camarasa, Antonio
Process Systems Engineering has shown a growing interest on ontologies to develop knowledge models, organize information, and produce software accordingly. Although software tools supporting the structure of ontologies exist, developing a PSE ontology is a creative procedure to be performed by human experts from each specific domain. This work explores the opportunities for automatic construction of domain ontologies. Specialised documentation can be selected and automatically parsed; next pattern recognition methods can be used to extract concepts and relations; finally, supervision is required to validate the automatic outcome, as well as to complete the task. The bulk of the development of an ontology is expected to result from the application of systematic procedures, thus the development time will be significantly reduced. Automatic methods were prepared and applied to the development of an ontology for batch processing based on the ISA88 standard. Methods are described and commented, and results are discussed from the comparison with a previous ontology for the same domain manually developed.
Tue, 17 Jan 2017 12:15:47 GMThttp://hdl.handle.net/2117/994422017-01-17T12:15:47ZFarreres de la Morena, XavierGraells Sobré, MoisèsRodríguez Hontoria, HoracioEspuña Camarasa, AntonioProcess Systems Engineering has shown a growing interest on ontologies to develop knowledge models, organize information, and produce software accordingly. Although software tools supporting the structure of ontologies exist, developing a PSE ontology is a creative procedure to be performed by human experts from each specific domain. This work explores the opportunities for automatic construction of domain ontologies. Specialised documentation can be selected and automatically parsed; next pattern recognition methods can be used to extract concepts and relations; finally, supervision is required to validate the automatic outcome, as well as to complete the task. The bulk of the development of an ontology is expected to result from the application of systematic procedures, thus the development time will be significantly reduced. Automatic methods were prepared and applied to the development of an ontology for batch processing based on the ISA88 standard. Methods are described and commented, and results are discussed from the comparison with a previous ontology for the same domain manually developed.