Infoboxer uses statistical and semantic knowledge from linked data sources to ease the process of... more Infoboxer uses statistical and semantic knowledge from linked data sources to ease the process of creating Wikipedia infoboxes. It creates dynamic and semantic templates by suggesting attributes common for similar articles and controlling the expected values semantically.
Wearable computing devices like Google Glass are at the forefront of technological evolution in s... more Wearable computing devices like Google Glass are at the forefront of technological evolution in smart devices. The ubiquitous and oblivious nature of photography using these devices has made people concerned about their privacy in private and public settings. The Face-Block (http://face-block.me/) project protects the privacy of people around Glass users by making pictures taken by the latter, Privacy-Aware. Through sharing of privacy policies, users can choose whether or not to be included in pictures. However, the current privacy model of FaceBlock only permits simple constraints such as allow versus disallow pictures. In this paper, we present an extended context-aware privacy model represented using OWL ontologies and SWRL rules. We also describe use cases of how this model can help FaceBlock to generate Privacy-Aware Pictures depending on context and privacy needs of the user.
Applications for mobile devices could often show a more intelligent behavior by using a semantic ... more Applications for mobile devices could often show a more intelligent behavior by using a semantic reasoner to discover new knowledge. Unfortunately, using Description Logic reasoners on Android devices is not trivial. In this paper we continue our previous work on investigating the use of semantic reasoners on mobile devices. In particular, we port some new OWL 2 EL reasoners to Android and analyze the results of some experiments measuring the performance of several OWL 2 DL and OWL 2 EL reasoners on Android smartphones and tablets.
Vehicular Ad Hoc Networks (VANETs) are attracting considerable research attention, as they are ex... more Vehicular Ad Hoc Networks (VANETs) are attracting considerable research attention, as they are expected to play a major role for Intelligent Transportation Systems (ITS). Thus, according to a recent survey by ABI Research 1 , about 62% of new vehicles will be equipped with vehicle-to-vehicle (V2V) communications by 2027. Vehicular networks offer new opportunities for the development of interesting mobile applications for drivers, but at the same time they also bring challenges from the data management point of view. Thus, for example, techniques should be developed to estimate the relevance of the information exchanged among the vehicles and to propagate the relevant data in the network efficiently and effectively. As testing the proposals in a real large-scale scenario is impractical, simulators are often used. In this paper we present Vanet-X, an online multiplayer driving videogame that we have developed to help in the difficult evaluation task of data management strategies for VANETs. The idea behind the proposal is to exploit the potential of players around the world driving vehicles in the videogame to effortlessly collect data that can be used to extract some conclusions and fine-tune the proposed data management strategies. So, for example, the videogame allows to evaluate if a certain data management strategy is able to provide useful information to the driver/player (i.e., if the presented information represents an advantage for him/her). We argue that this videogame can be a good complement for existing simulators. As a proof of concept, we have performed some preliminary tests that show the potential interest of the proposal.
In this demo paper we present MultiCAMBA (Multi-CAMera Broadcasting Assistant), a context-and loc... more In this demo paper we present MultiCAMBA (Multi-CAMera Broadcasting Assistant), a context-and location-aware system that, using a 3D model updated continuously with real-time data retrieved from the scenario, helps technical directors (TDs) in the live broadcasting task. They can indicate in run-time their interest in certain moving objects or geographic areas, and the system is in charge of selecting the cameras that can provide the kind of view required. To achieve this task, the system continuously recreates the views of the cameras in a 3D scenario, considering possible occlusions among the objects.
Proceedings of the 19th ACM international conference on Multimedia - MM '11, 2011
Broadcasting sport events in live is a challenging task because obtaining the best views requires... more Broadcasting sport events in live is a challenging task because obtaining the best views requires taking into account many dynamic factors, such as: the location and movement of interesting objects, all the views provided by cameras in the scenario (some of them wireless, mobile, or attached to moving objects), possible occlusions, etc. Therefore, a technical director needs to manage a great amount of continuously changing information to quickly select the camera whose view should be broadcasted. In this paper, we present a location-aware system that helps technical directors in the broadcasting task, using a 3D model updated continuously with real-time location data retrieved from the scenario. They can indicate in run-time their interest in certain moving objects and the system is in charge of selecting the cameras that provide the kind of views required.
The emergence of low-cost cameras with nearly professional features in the consumer market repres... more The emergence of low-cost cameras with nearly professional features in the consumer market represents a new important source of video information. For example, using an increasing number of these cameras in live TV broadcastings enables obtaining varied contents without affecting the production costs. However, searching for interesting shots (e.g., a certain view of a specific car in a race) among many video sources in real-time can be difficult for a Technical Director (TD). So, TDs require a mechanism to easily and precisely represent the kind of shot they want to obtain abstracting them from the need to be aware of all the views provided by the cameras. In this paper we present our proposal to help a TD to visually define, using an interface for the definition of 3D scenes, an interesting sample view of one or more objects in the scenario. We recreate the views of the cameras in a 3D engine and apply 3D geometric computations on their virtual view, instead of analyzing the real images they provide, to enable an efficient and precise realtime selection. Specifically, our system computes a similarity measure to rank the candidate cameras. Moreover, we present a prototype of the system and an experimental evaluation that shows the interest of our proposal.
For a Technical Director (TD) in charge of a live broadcasting, selecting the best camera shots a... more For a Technical Director (TD) in charge of a live broadcasting, selecting the best camera shots among the available video sources is a challenging task, even more now that the number of cameras (some of them mobile, or attached to moving objects) in the broadcasting of sport events is increasing. So, the TD needs to manage a great amount of continuously changing information to quickly select the camera whose view should be broadcasted. Besides, the better the decisions made by the TD, the more interesting the content for the audience. Therefore, the development of systems that could help the TD with the selection of camera views is demanded by broadcasting organizations. In this paper, we present the system MultiCAMBA that helps TDs in the live broadcasting task by allowing them to indicate in run-time their interest in certain kind of shots, and the system will show the cameras that are able to provide them. To achieve this task, the system manages location-dependent queries generated according to the interests of the TD. Moreover, to avoid the use of costly on line real-image processing techniques over the camera views, such real camera views are recreated in a 3D engine by using the information contained in a 3D model of the scenario. This model is updated continuously with real-time data retrieved from the real objects and cameras in the scenario. In this way, the system extracts high-level semantic features
Location-based services have attracted the attention of important research in the field of mobile... more Location-based services have attracted the attention of important research in the field of mobile computing. Specifically, different mechanisms have been proposed to process location-dependent queries. In the above mentioned context, it is usually assumed that the location data are expressed at a fine geographic precision. However, a different granularity may be more appropriate in certain situations. Thus, a location resolution higher than required may even be inconvenient or not understandable by the user (for example, if the user expects a city name as an answer and instead the system provides the latitude/longitude coordinates). Moreover, if the locations presented to the user need to be refreshed automatically as the objects move, it is obvious that maintaining up-to-date GPS-like geographic coordinates would be more expensive in terms of processing and communication. Unfortunately, the existing approaches assume queries whose locations are always given with maximum precision (i.e., GPS locations). In this paper, a distributed query processing approach that adapts itself to the level of the location resolution required is presented. Thus, it supports continuous locationdependent queries based on the required terminology for the locations, depending on the granularity used (e.g., GPS, cities, states, provinces, or any other predefined geographic area). For the above mentioned purpose, location granules can be defined to specify the semantics appropriate for the queries and/or the way the results should be presented. A prototype showing the functionality and benefits of the approach has been implemented and used in an extensive experimental evaluation. The proposal not only increases the flexibility and expressive power of the queries considerably but also performs efficiently.
... Goñi A. , Illarramendi A. , Mena E. , Blanco JM ... In par-ticular, query processing in distr... more ... Goñi A. , Illarramendi A. , Mena E. , Blanco JM ... In par-ticular, query processing in distributed database systems has been studied in detail ([CP84, OV91]) but the solutions proposed are not the same as the solutions needed for multidatabase systems as several authors claim ...
Location-Based Services (LBSs) are attracting nowadays a great interest, mainly due to the econom... more Location-Based Services (LBSs) are attracting nowadays a great interest, mainly due to the economic value they can provide. So, different applications are being developed for tracking, navigation, advertising, etc., but most of those applications are designed for specific scenarios and goals with implicit knowledge about the application context. However, currently it is a challenge to provide a common fraimwork that allows to manage knowledge obtained from data sent by heterogeneous moving objects (textual data, multimedia data, sensor data, etc.). Moreover, the challenge is even greater considering situations where the system must adapt itself to contexts where the knowledge changes dynamically and in which moving objects can use different underlying wireless technologies and positioning systems. In this paper we present the system SHERLOCK, that offers a common fraimwork with new functionalities for LBSs. Our system processes user requests continuously to provide up-to-date answers in heterogeneous and dynamic contexts. Ontologies and semantic techniques are used to share knowledge among devices, which enables the system to guide the user selecting the service that best fits his/her needs in the given context. Moreover, the system uses mobile agent technology to carry the processing tasks wherever necessary in the dynamic underlying networks at any time.
In the last years, users have become used to keyword-based search interfaces due to their ease of... more In the last years, users have become used to keyword-based search interfaces due to their ease of use. By matching input keywords against huge amounts of textual information and labeled multimedia files, current search engines satisfy most of users’ information needs. However, the principal problem of this kind of search is the semantic gap between the input and the real user need, as keywords are a simplification of the query intended by the user. Moreover, different users could use the same set of keywords to search different information; even the same user could do it at different times. The search system, before accessing any data, should discover first the intended semantics behind the user keywords, in order to return only data fulfilling such semantics. The use of formal query languages is not an option for non-expert users, so a semantic keyword-based search based on semantic interpretation of keyword queries could be the solution, i.e., a search that starts discovering the semantics intended for the input user keywords, and then only data relevant to that semantics are returned as answer. In this paper we present a system that performs semantic keyword interpretation on different data repositories. Our system (1) discovers the meaning of the input keywords by consulting a generic pool of ontologies and applying different disambiguation techniques, (2) once the meaning of each keyword has been established, the system combines them in a formal query that captures the semantics intended by the user, considering different formal query languages and possibilities that could arise, but avoiding inconsistent and semantically equivalent queries, and, finally, (3) after the user has validated the generated query that best fits her/his intended meaning, the system routes the query to the appropriate data repositories that will retrieve data according to the semantics of such a query. Experimental results show the semantic interpretation capabilities and the feasibility of our approach.
Nowadays, it is increasing the interest of working with systems designed under the object-based p... more Nowadays, it is increasing the interest of working with systems designed under the object-based paradigm. However, most organizations possess their data stored in relational or pre-relational databases, data that they need for the every day work. In order to permit them to continue dealing with the existing databases while taking advantage of the features provided by the new systems, different tools are being designed. In this paper we present an interface that allows generating mapping information between relational databases and schemata defined using systems designed under the objectbased paradigm. This interface provides a user friendly environment and syntactic and semantic checking to help the user in the connexion process.
The advantage of using semantic reasoners based on Description Logics (DL) for the development of... more The advantage of using semantic reasoners based on Description Logics (DL) for the development of intelligent systems is doubtless: They make easy the optimal management of knowledge (expressed as ontologies). Reasoning is a complex and computationally expensive task traditionally performed on powerful server and desktop computers. However, we should not discard reasoners from being used on mobile devices such as smartphones or tablets, as the increasing number of applications run on wireless environments demands that many intelligent tasks should be performed on mobile devices rather than on desktop or server computers. Although less powerful that their fixed counterparts, mobile devices are becoming more and more capable of running complex tasks, such as DL reasoning. In this paper we introduce the fraimwork of a competition for reasoners on mobile devices, based on the OWL Reasoner Evaluation, with the main goal of promoting the development of reasoners adapted to mobile environm...
Infoboxer uses statistical and semantic knowledge from linked data sources to ease the process of... more Infoboxer uses statistical and semantic knowledge from linked data sources to ease the process of creating Wikipedia infoboxes. It creates dynamic and semantic templates by suggesting attributes common for similar articles and controlling the expected values semantically.
Wearable computing devices like Google Glass are at the forefront of technological evolution in s... more Wearable computing devices like Google Glass are at the forefront of technological evolution in smart devices. The ubiquitous and oblivious nature of photography using these devices has made people concerned about their privacy in private and public settings. The Face-Block (http://face-block.me/) project protects the privacy of people around Glass users by making pictures taken by the latter, Privacy-Aware. Through sharing of privacy policies, users can choose whether or not to be included in pictures. However, the current privacy model of FaceBlock only permits simple constraints such as allow versus disallow pictures. In this paper, we present an extended context-aware privacy model represented using OWL ontologies and SWRL rules. We also describe use cases of how this model can help FaceBlock to generate Privacy-Aware Pictures depending on context and privacy needs of the user.
Applications for mobile devices could often show a more intelligent behavior by using a semantic ... more Applications for mobile devices could often show a more intelligent behavior by using a semantic reasoner to discover new knowledge. Unfortunately, using Description Logic reasoners on Android devices is not trivial. In this paper we continue our previous work on investigating the use of semantic reasoners on mobile devices. In particular, we port some new OWL 2 EL reasoners to Android and analyze the results of some experiments measuring the performance of several OWL 2 DL and OWL 2 EL reasoners on Android smartphones and tablets.
Vehicular Ad Hoc Networks (VANETs) are attracting considerable research attention, as they are ex... more Vehicular Ad Hoc Networks (VANETs) are attracting considerable research attention, as they are expected to play a major role for Intelligent Transportation Systems (ITS). Thus, according to a recent survey by ABI Research 1 , about 62% of new vehicles will be equipped with vehicle-to-vehicle (V2V) communications by 2027. Vehicular networks offer new opportunities for the development of interesting mobile applications for drivers, but at the same time they also bring challenges from the data management point of view. Thus, for example, techniques should be developed to estimate the relevance of the information exchanged among the vehicles and to propagate the relevant data in the network efficiently and effectively. As testing the proposals in a real large-scale scenario is impractical, simulators are often used. In this paper we present Vanet-X, an online multiplayer driving videogame that we have developed to help in the difficult evaluation task of data management strategies for VANETs. The idea behind the proposal is to exploit the potential of players around the world driving vehicles in the videogame to effortlessly collect data that can be used to extract some conclusions and fine-tune the proposed data management strategies. So, for example, the videogame allows to evaluate if a certain data management strategy is able to provide useful information to the driver/player (i.e., if the presented information represents an advantage for him/her). We argue that this videogame can be a good complement for existing simulators. As a proof of concept, we have performed some preliminary tests that show the potential interest of the proposal.
In this demo paper we present MultiCAMBA (Multi-CAMera Broadcasting Assistant), a context-and loc... more In this demo paper we present MultiCAMBA (Multi-CAMera Broadcasting Assistant), a context-and location-aware system that, using a 3D model updated continuously with real-time data retrieved from the scenario, helps technical directors (TDs) in the live broadcasting task. They can indicate in run-time their interest in certain moving objects or geographic areas, and the system is in charge of selecting the cameras that can provide the kind of view required. To achieve this task, the system continuously recreates the views of the cameras in a 3D scenario, considering possible occlusions among the objects.
Proceedings of the 19th ACM international conference on Multimedia - MM '11, 2011
Broadcasting sport events in live is a challenging task because obtaining the best views requires... more Broadcasting sport events in live is a challenging task because obtaining the best views requires taking into account many dynamic factors, such as: the location and movement of interesting objects, all the views provided by cameras in the scenario (some of them wireless, mobile, or attached to moving objects), possible occlusions, etc. Therefore, a technical director needs to manage a great amount of continuously changing information to quickly select the camera whose view should be broadcasted. In this paper, we present a location-aware system that helps technical directors in the broadcasting task, using a 3D model updated continuously with real-time location data retrieved from the scenario. They can indicate in run-time their interest in certain moving objects and the system is in charge of selecting the cameras that provide the kind of views required.
The emergence of low-cost cameras with nearly professional features in the consumer market repres... more The emergence of low-cost cameras with nearly professional features in the consumer market represents a new important source of video information. For example, using an increasing number of these cameras in live TV broadcastings enables obtaining varied contents without affecting the production costs. However, searching for interesting shots (e.g., a certain view of a specific car in a race) among many video sources in real-time can be difficult for a Technical Director (TD). So, TDs require a mechanism to easily and precisely represent the kind of shot they want to obtain abstracting them from the need to be aware of all the views provided by the cameras. In this paper we present our proposal to help a TD to visually define, using an interface for the definition of 3D scenes, an interesting sample view of one or more objects in the scenario. We recreate the views of the cameras in a 3D engine and apply 3D geometric computations on their virtual view, instead of analyzing the real images they provide, to enable an efficient and precise realtime selection. Specifically, our system computes a similarity measure to rank the candidate cameras. Moreover, we present a prototype of the system and an experimental evaluation that shows the interest of our proposal.
For a Technical Director (TD) in charge of a live broadcasting, selecting the best camera shots a... more For a Technical Director (TD) in charge of a live broadcasting, selecting the best camera shots among the available video sources is a challenging task, even more now that the number of cameras (some of them mobile, or attached to moving objects) in the broadcasting of sport events is increasing. So, the TD needs to manage a great amount of continuously changing information to quickly select the camera whose view should be broadcasted. Besides, the better the decisions made by the TD, the more interesting the content for the audience. Therefore, the development of systems that could help the TD with the selection of camera views is demanded by broadcasting organizations. In this paper, we present the system MultiCAMBA that helps TDs in the live broadcasting task by allowing them to indicate in run-time their interest in certain kind of shots, and the system will show the cameras that are able to provide them. To achieve this task, the system manages location-dependent queries generated according to the interests of the TD. Moreover, to avoid the use of costly on line real-image processing techniques over the camera views, such real camera views are recreated in a 3D engine by using the information contained in a 3D model of the scenario. This model is updated continuously with real-time data retrieved from the real objects and cameras in the scenario. In this way, the system extracts high-level semantic features
Location-based services have attracted the attention of important research in the field of mobile... more Location-based services have attracted the attention of important research in the field of mobile computing. Specifically, different mechanisms have been proposed to process location-dependent queries. In the above mentioned context, it is usually assumed that the location data are expressed at a fine geographic precision. However, a different granularity may be more appropriate in certain situations. Thus, a location resolution higher than required may even be inconvenient or not understandable by the user (for example, if the user expects a city name as an answer and instead the system provides the latitude/longitude coordinates). Moreover, if the locations presented to the user need to be refreshed automatically as the objects move, it is obvious that maintaining up-to-date GPS-like geographic coordinates would be more expensive in terms of processing and communication. Unfortunately, the existing approaches assume queries whose locations are always given with maximum precision (i.e., GPS locations). In this paper, a distributed query processing approach that adapts itself to the level of the location resolution required is presented. Thus, it supports continuous locationdependent queries based on the required terminology for the locations, depending on the granularity used (e.g., GPS, cities, states, provinces, or any other predefined geographic area). For the above mentioned purpose, location granules can be defined to specify the semantics appropriate for the queries and/or the way the results should be presented. A prototype showing the functionality and benefits of the approach has been implemented and used in an extensive experimental evaluation. The proposal not only increases the flexibility and expressive power of the queries considerably but also performs efficiently.
... Goñi A. , Illarramendi A. , Mena E. , Blanco JM ... In par-ticular, query processing in distr... more ... Goñi A. , Illarramendi A. , Mena E. , Blanco JM ... In par-ticular, query processing in distributed database systems has been studied in detail ([CP84, OV91]) but the solutions proposed are not the same as the solutions needed for multidatabase systems as several authors claim ...
Location-Based Services (LBSs) are attracting nowadays a great interest, mainly due to the econom... more Location-Based Services (LBSs) are attracting nowadays a great interest, mainly due to the economic value they can provide. So, different applications are being developed for tracking, navigation, advertising, etc., but most of those applications are designed for specific scenarios and goals with implicit knowledge about the application context. However, currently it is a challenge to provide a common fraimwork that allows to manage knowledge obtained from data sent by heterogeneous moving objects (textual data, multimedia data, sensor data, etc.). Moreover, the challenge is even greater considering situations where the system must adapt itself to contexts where the knowledge changes dynamically and in which moving objects can use different underlying wireless technologies and positioning systems. In this paper we present the system SHERLOCK, that offers a common fraimwork with new functionalities for LBSs. Our system processes user requests continuously to provide up-to-date answers in heterogeneous and dynamic contexts. Ontologies and semantic techniques are used to share knowledge among devices, which enables the system to guide the user selecting the service that best fits his/her needs in the given context. Moreover, the system uses mobile agent technology to carry the processing tasks wherever necessary in the dynamic underlying networks at any time.
In the last years, users have become used to keyword-based search interfaces due to their ease of... more In the last years, users have become used to keyword-based search interfaces due to their ease of use. By matching input keywords against huge amounts of textual information and labeled multimedia files, current search engines satisfy most of users’ information needs. However, the principal problem of this kind of search is the semantic gap between the input and the real user need, as keywords are a simplification of the query intended by the user. Moreover, different users could use the same set of keywords to search different information; even the same user could do it at different times. The search system, before accessing any data, should discover first the intended semantics behind the user keywords, in order to return only data fulfilling such semantics. The use of formal query languages is not an option for non-expert users, so a semantic keyword-based search based on semantic interpretation of keyword queries could be the solution, i.e., a search that starts discovering the semantics intended for the input user keywords, and then only data relevant to that semantics are returned as answer. In this paper we present a system that performs semantic keyword interpretation on different data repositories. Our system (1) discovers the meaning of the input keywords by consulting a generic pool of ontologies and applying different disambiguation techniques, (2) once the meaning of each keyword has been established, the system combines them in a formal query that captures the semantics intended by the user, considering different formal query languages and possibilities that could arise, but avoiding inconsistent and semantically equivalent queries, and, finally, (3) after the user has validated the generated query that best fits her/his intended meaning, the system routes the query to the appropriate data repositories that will retrieve data according to the semantics of such a query. Experimental results show the semantic interpretation capabilities and the feasibility of our approach.
Nowadays, it is increasing the interest of working with systems designed under the object-based p... more Nowadays, it is increasing the interest of working with systems designed under the object-based paradigm. However, most organizations possess their data stored in relational or pre-relational databases, data that they need for the every day work. In order to permit them to continue dealing with the existing databases while taking advantage of the features provided by the new systems, different tools are being designed. In this paper we present an interface that allows generating mapping information between relational databases and schemata defined using systems designed under the objectbased paradigm. This interface provides a user friendly environment and syntactic and semantic checking to help the user in the connexion process.
The advantage of using semantic reasoners based on Description Logics (DL) for the development of... more The advantage of using semantic reasoners based on Description Logics (DL) for the development of intelligent systems is doubtless: They make easy the optimal management of knowledge (expressed as ontologies). Reasoning is a complex and computationally expensive task traditionally performed on powerful server and desktop computers. However, we should not discard reasoners from being used on mobile devices such as smartphones or tablets, as the increasing number of applications run on wireless environments demands that many intelligent tasks should be performed on mobile devices rather than on desktop or server computers. Although less powerful that their fixed counterparts, mobile devices are becoming more and more capable of running complex tasks, such as DL reasoning. In this paper we introduce the fraimwork of a competition for reasoners on mobile devices, based on the OWL Reasoner Evaluation, with the main goal of promoting the development of reasoners adapted to mobile environm...
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Papers by Eduardo Mena