The Semantic Web and collaborative tagging are two complementary approaches aiming at making info... more The Semantic Web and collaborative tagging are two complementary approaches aiming at making information search, retrieval, navigation and knowledge discovery easier. While the Semantic Web enforces semantics top-down via the use of ontologies, collaborative tagging tries to obtain semantics in a bottom-up fashion. Del. icio. us and flickr are success stories of collaborative tagging; the winners of the Semantic Web Challenge demonstrate the success of the Semantic Web. Still, both approaches face open issues.
Abstract The efficient reasoning about entities across distributed information sources and their ... more Abstract The efficient reasoning about entities across distributed information sources and their efficient resolution are crucial prerequisites if the prescriptions of the Semantic Web movement are to come into reality. These goals along with some of the most important principal and technical issues of the Internet and the Web are presented in this work. Entity registry systems provide capabilities like storing, serving and resolving data entities which could greatly facilitate the Semantic Web.
Abstract Until recently, most data integration techniques involved central components, eg, global... more Abstract Until recently, most data integration techniques involved central components, eg, global schemas, to enable transparent access to heterogeneous databases. Today, however, with the democratization of tools facilitating knowledge elicitation in machine-processable formats, one cannot rely on global, centralized schemas anymore as knowledge creation and consumption are getting more and more dynamic and decentralized.
Abstract. The proliferation of digital camera devices (stand-alone or combined with cell phones),... more Abstract. The proliferation of digital camera devices (stand-alone or combined with cell phones), new protocols such as MMS and the desire of people to communicate and share their experience calls for new systems to support these needs in new Internet-scale infrastructures. In this paper we outline our plans for a Internet-scale P2P system that enables users to share (globally or only within a group) and efficiently locate photographs based on semi-automatically provided meta-information (by the devices and the user).
Abstract. We consider the problem of analytically evaluating semantic interoperability in large-s... more Abstract. We consider the problem of analytically evaluating semantic interoperability in large-scale networks of schemas interconnected through pairwise schema mappings. Our heuristics are based on a graphtheoretic framework capturing important statistical properties of the graphs. We validate our heuristics on a real collection of interconnected bioinformatic databases registered with the Sequence Retrieval System (SRS).
Abstract In the past, the problem of semantic interoperability in information systems was mostly ... more Abstract In the past, the problem of semantic interoperability in information systems was mostly solved by means of centralization, both at a system and at a logical level. This approach has been successful to a certain extent, but offers limited scalability and flexibility.
Abstract The rise of GPS and broadband-speed wireless devices has led to tremendous excitement ab... more Abstract The rise of GPS and broadband-speed wireless devices has led to tremendous excitement about a range of applications broadly characterized as¿ location based services¿. Current database storage systems, however, are inadequate for manipulating the very large and dynamic spatio-temporal data sets required to support such services.
Abstract In CIDR 2009, we presented a collection of requirements for SciDB, a DBMS that would mee... more Abstract In CIDR 2009, we presented a collection of requirements for SciDB, a DBMS that would meet the needs of scientific users. These included a nested-array data model, science-specific operations such as regrid, and support for uncertainty, lineage, and named versions. In this paper, we present an overview of SciDB's key features and outline a demonstration of the first version of SciDB on data and operations from one of our lighthouse users, the Large Synoptic Survey Telescope (LSST).
Abstract We present HAMLET, a suite of principles, scoring models and algorithms to automatically... more Abstract We present HAMLET, a suite of principles, scoring models and algorithms to automatically propagate metadata along edges in a document neighborhood. As a showcase scenario we consider tag prediction in community-based Web 2.0 tagging applications. Experiments using real-world data demonstrate the viability of our approach in large-scale environments where tags are scarce.
Abstract GridVine is a Peer Data Management System based on a decentralized access structure. Bui... more Abstract GridVine is a Peer Data Management System based on a decentralized access structure. Built following the principle of data independence, it separates a logical layer--where data, schemas and mappings are managed--from a physical layer consisting of a structured Peer-to-Peer network supporting efficient routing of messages and index load-balancing. Our system is totally decentralized, yet it fosters semantic interoperability through pairwise schema mappings and query reformulation.
Abstract With the commoditization of digital devices, personal information and media sharing is b... more Abstract With the commoditization of digital devices, personal information and media sharing is becoming a key application on the pervasive Web. In such a context, data annotation rather than data production is the main bottleneck. Metadata scarcity represents a major obstacle preventing efficient information processing in large and heterogeneous communities.
The Semantic Web (SW) has been envisioned to enable software tools or Web Services, respectively,... more The Semantic Web (SW) has been envisioned to enable software tools or Web Services, respectively, to process information provided on the Web automatically. For this purpose, languages for representing the semantics of data by means of ontologies have been proposed such as RDF (S) and OWL. While the semantics of RDF (S) requires a non-standard model-theory that goes beyond first order logics, OWL is intended to model subsets of first order logics. OWL consists of three variants that are layered on each other.
Abstract Programmatic access to data and tools through the web using so-called web services has a... more Abstract Programmatic access to data and tools through the web using so-called web services has an important role to play in bioinformatics. In this article, we discuss the most popular approaches based on SOAP/WS-I and REST and describe our, a cross section of the community, experiences with providing and using web services in the context of biological sequence analysis. We briefly review main technological approaches as well as best practice hints that are useful for both users and developers.
Abstract. We consider the problem of tag prediction in collaborative tagging systems where users ... more Abstract. We consider the problem of tag prediction in collaborative tagging systems where users share and annotate resources on the Web. We put forward HAMLET, a novel approach to automatically propagate tags along the edges of a graph which relates similar documents. We identify the core principles underlying tag propagation for which we derive suitable scoring models combined in one overall ranking formula.
The database and information retrieval communities have long been recognized as being irreconcila... more The database and information retrieval communities have long been recognized as being irreconcilable. Today, however, we witness a surprising convergence of the techniques used by both communities in decentralized, large-scale environments. The newly emerging field of reputation based trust management, borrowing techniques from both communities, best demonstrates this claim.
This course is an introduction to Java programming and software engineering. It is designed for t... more This course is an introduction to Java programming and software engineering. It is designed for those who have little or no programming experience in Java and covers concepts useful to 6.005. The focus is on developing high quality, working software that solves real problems. Students will learn the fundamentals of Java, and how to use 3rd party libraries to get more done with less work. Each session includes one hour of lecture and one hour of assisted lab work. Short labs are assigned with each lecture.
Abstract The proliferation of GPS devices has led to a substantial interest in location based ser... more Abstract The proliferation of GPS devices has led to a substantial interest in location based services. In particular, modern vehicles can generate an incredible amount of drive data. However, current storage systems are not optimized for storing and querying such large spatial-temporal data sets. In this demonstration, we show the performance of the TrajStore system, a dynamic storage system optimized for quickly accessing data in a particular spatial-temporal region.
Amicalola workshop on DB-IS Research for Semantic Web and Enterprises was held in April 2002(http... more Amicalola workshop on DB-IS Research for Semantic Web and Enterprises was held in April 2002(http://lsdis. cs. uga. edu/SemNSF/). Secluded and cozy retreat in Georgia mountains provided an excellent environment for high quality discussions between a set of invited senior researchers from within and outside of database and information systems community.
Abstract We tackle the problem of entity linking for large collections of online pages; Our syste... more Abstract We tackle the problem of entity linking for large collections of online pages; Our system, ZenCrowd, identifies entities from natural language text using state of the art techniques and automatically connects them to the Linked Open Data cloud. We show how one can take advantage of human intelligence to improve the quality of the links by dynamically generating micro-tasks on an online crowdsourcing platform.
Abstract In this paper, we describe a versioned database storage manager we are developing for th... more Abstract In this paper, we describe a versioned database storage manager we are developing for the SciDB scientific database. The system is designed to efficiently store and retrieve array-oriented data, exposing a" no-overwrite" storage model in which each update creates a new" version" of an array. This makes it possible to perform comparisons of versions produced at different times or by different algorithms, and to create complex chains and trees of versions.
The Semantic Web and collaborative tagging are two complementary approaches aiming at making info... more The Semantic Web and collaborative tagging are two complementary approaches aiming at making information search, retrieval, navigation and knowledge discovery easier. While the Semantic Web enforces semantics top-down via the use of ontologies, collaborative tagging tries to obtain semantics in a bottom-up fashion. Del. icio. us and flickr are success stories of collaborative tagging; the winners of the Semantic Web Challenge demonstrate the success of the Semantic Web. Still, both approaches face open issues.
Abstract The efficient reasoning about entities across distributed information sources and their ... more Abstract The efficient reasoning about entities across distributed information sources and their efficient resolution are crucial prerequisites if the prescriptions of the Semantic Web movement are to come into reality. These goals along with some of the most important principal and technical issues of the Internet and the Web are presented in this work. Entity registry systems provide capabilities like storing, serving and resolving data entities which could greatly facilitate the Semantic Web.
Abstract Until recently, most data integration techniques involved central components, eg, global... more Abstract Until recently, most data integration techniques involved central components, eg, global schemas, to enable transparent access to heterogeneous databases. Today, however, with the democratization of tools facilitating knowledge elicitation in machine-processable formats, one cannot rely on global, centralized schemas anymore as knowledge creation and consumption are getting more and more dynamic and decentralized.
Abstract. The proliferation of digital camera devices (stand-alone or combined with cell phones),... more Abstract. The proliferation of digital camera devices (stand-alone or combined with cell phones), new protocols such as MMS and the desire of people to communicate and share their experience calls for new systems to support these needs in new Internet-scale infrastructures. In this paper we outline our plans for a Internet-scale P2P system that enables users to share (globally or only within a group) and efficiently locate photographs based on semi-automatically provided meta-information (by the devices and the user).
Abstract. We consider the problem of analytically evaluating semantic interoperability in large-s... more Abstract. We consider the problem of analytically evaluating semantic interoperability in large-scale networks of schemas interconnected through pairwise schema mappings. Our heuristics are based on a graphtheoretic framework capturing important statistical properties of the graphs. We validate our heuristics on a real collection of interconnected bioinformatic databases registered with the Sequence Retrieval System (SRS).
Abstract In the past, the problem of semantic interoperability in information systems was mostly ... more Abstract In the past, the problem of semantic interoperability in information systems was mostly solved by means of centralization, both at a system and at a logical level. This approach has been successful to a certain extent, but offers limited scalability and flexibility.
Abstract The rise of GPS and broadband-speed wireless devices has led to tremendous excitement ab... more Abstract The rise of GPS and broadband-speed wireless devices has led to tremendous excitement about a range of applications broadly characterized as¿ location based services¿. Current database storage systems, however, are inadequate for manipulating the very large and dynamic spatio-temporal data sets required to support such services.
Abstract In CIDR 2009, we presented a collection of requirements for SciDB, a DBMS that would mee... more Abstract In CIDR 2009, we presented a collection of requirements for SciDB, a DBMS that would meet the needs of scientific users. These included a nested-array data model, science-specific operations such as regrid, and support for uncertainty, lineage, and named versions. In this paper, we present an overview of SciDB's key features and outline a demonstration of the first version of SciDB on data and operations from one of our lighthouse users, the Large Synoptic Survey Telescope (LSST).
Abstract We present HAMLET, a suite of principles, scoring models and algorithms to automatically... more Abstract We present HAMLET, a suite of principles, scoring models and algorithms to automatically propagate metadata along edges in a document neighborhood. As a showcase scenario we consider tag prediction in community-based Web 2.0 tagging applications. Experiments using real-world data demonstrate the viability of our approach in large-scale environments where tags are scarce.
Abstract GridVine is a Peer Data Management System based on a decentralized access structure. Bui... more Abstract GridVine is a Peer Data Management System based on a decentralized access structure. Built following the principle of data independence, it separates a logical layer--where data, schemas and mappings are managed--from a physical layer consisting of a structured Peer-to-Peer network supporting efficient routing of messages and index load-balancing. Our system is totally decentralized, yet it fosters semantic interoperability through pairwise schema mappings and query reformulation.
Abstract With the commoditization of digital devices, personal information and media sharing is b... more Abstract With the commoditization of digital devices, personal information and media sharing is becoming a key application on the pervasive Web. In such a context, data annotation rather than data production is the main bottleneck. Metadata scarcity represents a major obstacle preventing efficient information processing in large and heterogeneous communities.
The Semantic Web (SW) has been envisioned to enable software tools or Web Services, respectively,... more The Semantic Web (SW) has been envisioned to enable software tools or Web Services, respectively, to process information provided on the Web automatically. For this purpose, languages for representing the semantics of data by means of ontologies have been proposed such as RDF (S) and OWL. While the semantics of RDF (S) requires a non-standard model-theory that goes beyond first order logics, OWL is intended to model subsets of first order logics. OWL consists of three variants that are layered on each other.
Abstract Programmatic access to data and tools through the web using so-called web services has a... more Abstract Programmatic access to data and tools through the web using so-called web services has an important role to play in bioinformatics. In this article, we discuss the most popular approaches based on SOAP/WS-I and REST and describe our, a cross section of the community, experiences with providing and using web services in the context of biological sequence analysis. We briefly review main technological approaches as well as best practice hints that are useful for both users and developers.
Abstract. We consider the problem of tag prediction in collaborative tagging systems where users ... more Abstract. We consider the problem of tag prediction in collaborative tagging systems where users share and annotate resources on the Web. We put forward HAMLET, a novel approach to automatically propagate tags along the edges of a graph which relates similar documents. We identify the core principles underlying tag propagation for which we derive suitable scoring models combined in one overall ranking formula.
The database and information retrieval communities have long been recognized as being irreconcila... more The database and information retrieval communities have long been recognized as being irreconcilable. Today, however, we witness a surprising convergence of the techniques used by both communities in decentralized, large-scale environments. The newly emerging field of reputation based trust management, borrowing techniques from both communities, best demonstrates this claim.
This course is an introduction to Java programming and software engineering. It is designed for t... more This course is an introduction to Java programming and software engineering. It is designed for those who have little or no programming experience in Java and covers concepts useful to 6.005. The focus is on developing high quality, working software that solves real problems. Students will learn the fundamentals of Java, and how to use 3rd party libraries to get more done with less work. Each session includes one hour of lecture and one hour of assisted lab work. Short labs are assigned with each lecture.
Abstract The proliferation of GPS devices has led to a substantial interest in location based ser... more Abstract The proliferation of GPS devices has led to a substantial interest in location based services. In particular, modern vehicles can generate an incredible amount of drive data. However, current storage systems are not optimized for storing and querying such large spatial-temporal data sets. In this demonstration, we show the performance of the TrajStore system, a dynamic storage system optimized for quickly accessing data in a particular spatial-temporal region.
Amicalola workshop on DB-IS Research for Semantic Web and Enterprises was held in April 2002(http... more Amicalola workshop on DB-IS Research for Semantic Web and Enterprises was held in April 2002(http://lsdis. cs. uga. edu/SemNSF/). Secluded and cozy retreat in Georgia mountains provided an excellent environment for high quality discussions between a set of invited senior researchers from within and outside of database and information systems community.
Abstract We tackle the problem of entity linking for large collections of online pages; Our syste... more Abstract We tackle the problem of entity linking for large collections of online pages; Our system, ZenCrowd, identifies entities from natural language text using state of the art techniques and automatically connects them to the Linked Open Data cloud. We show how one can take advantage of human intelligence to improve the quality of the links by dynamically generating micro-tasks on an online crowdsourcing platform.
Abstract In this paper, we describe a versioned database storage manager we are developing for th... more Abstract In this paper, we describe a versioned database storage manager we are developing for the SciDB scientific database. The system is designed to efficiently store and retrieve array-oriented data, exposing a" no-overwrite" storage model in which each update creates a new" version" of an array. This makes it possible to perform comparisons of versions produced at different times or by different algorithms, and to create complex chains and trees of versions.
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