Peer-to-peer(P2P)computingiscurrentlyattractingenormousmediaattention, spurred by the popularity of ?le sharing systems such as Napster, Gnutella and Morpheus. In P2P systems a very large number of autonomous computing nodes (the peers) pool together their resources and rely on each other for data and services. The wealth of business opportunities promised by P2P networks has gene- ted much industrial interest recently, and has resulted in the creation of various industrial projects, startup companies, and special interest groups. Researchers from distributed computing, networks, agents and databases have also become excited about the P2P vision, and papers tackling open problems in this area have started appearing in high-quality conferences and workshops. Much of the recent research on P2P systems seems to be carried out by - search groups with a primary interest in distributed computation and networks. This workshop concentrated on the impact that current database research can have on P2P computing and vice versa. Although researchers in distributed data structures and databases have been working on related issues for a long time, the developed techniques are simply not adequate for the new paradigm.

This volume contains the papers from the technical programmeof the 5th Eu- pean Semantic Web Conference, ESWC 2008, that took place during June 1-5, 2008 in Tenerife, Islas Canarias, Spain. ESWC 2008 was the latest in a series of annual, international events foc- ing on the dissemination and discussion of the latest research and applications of Semantic Web technologies. The call for papers saw over 270 submissions, a comparable ?gure to the previous year, indicating that the conference series has reached a certain level of maturity. The review process was organized - ing a two-tiered system. First, each submission was reviewed by at least three members of the ProgrammeCommittee. Submissions were also assignedto a - niorProgrammeCommitteemember, wholed discussionsbetweenreviewersand provided a metareview and provisional decision. A physical Programme C- mittee meeting was then held, where the ?nal decisions weremade. Competition was as strong as ever, and the Programme Committee selected 51 papers to be presented at the conference. In addition to the technical research paper track, a system demo track was included, withits ownreviewprocess. Twenty-?vedemo paperswereselectedfor publication. System demo authors were given the opportunity to present their workin dedicated sessionsduring the conference, while anevening receptionwas also devoted to the presentation of posters and demonstrations of systems. As in past years, ESWC subscribed to the call to "eat our own dog food," withthepublicationofarichsetofsemanticmetadatadescribingtheconference. Three invited talks were given by distinguished scientists: Nigel Shadbolt (Garlik Ltd.

The 9th International Conference on Extending Database Technology, EDBT 2004, was held in Heraklion, Crete, Greece, during March 14-18, 2004. The EDBT series of conferences is an established and prestigious forum for the exchange of the latest research results in data management. Held every two years in an attractive European location, the conference provides unique opp- tunities for database researchers, practitioners, developers, and users to explore new ideas, techniques, and tools, and to exchange experiences. The previous events were held in Venice, Vienna, Cambridge, Avignon, Valencia, Konstanz, and Prague. EDBT 2004 had the theme "new challenges for database technology," with the goal of encouraging researchers to take a greater interest in the current exciting technological and application advancements and to devise and address new research and development directions for database technology. From its early days, database technology has been challenged and advanced by new uses and applications, and it continues to evolve along with application requirements and hardware advances. Today's DBMS technology faces yet several new challenges. Technological trends and new computation paradigms, and applications such as pervasive and ubiquitous computing, grid computing, bioinformatics, trust management, virtual communities, and digital asset management, to name just a few, require database technology to be deployed in a variety of environments and for a number of di?erent purposes. Such an extensive deployment will also require trustworthy, resilient database systems, as well as easy-to-manage and ?exible ones, to which we can entrust our data in whatever form they are.

Peer-to-peer(P2P)computingiscurrentlyattractingenormousmediaattention, spurred by the popularity of ?le sharing systems such as Napster, Gnutella and Morpheus. In P2P systems a very large number of autonomous computing nodes (the peers) pool together their resources and rely on each other for data and services. The wealth of business opportunities promised by P2P networks has gene- ted much industrial interest recently, and has resulted in the creation of various industrial projects, startup companies, and special interest groups. Researchers from distributed computing, networks, agents and databases have also become excited about the P2P vision, and papers tackling open problems in this area have started appearing in high-quality conferences and workshops. Much of the recent research on P2P systems seems to be carried out by - search groups with a primary interest in distributed computation and networks. This workshop concentrated on the impact that current database research can have on P2P computing and vice versa. Although researchers in distributed data structures and databases have been working on related issues for a long time, the developed techniques are simply not adequate for the new paradigm.

A summary of research carried out in the CHOROCHRONOS Project, established as an EC-funded Training and Mobility Research Network with the objective of studying the design, implementation, and application of spatio-temporal database management systems. The nine coherent chapters by leading research groups are written in a tutorial style, making the research contributions of the project accessible to a wider audience interested in spatio-temporal information processing. Following an introductory overview, the book presents chapters on ontologies for spatio-temporal databases, conceptual models, spatio-temporal models and languages, access methods and query processing, architectures and implementation of spatio-temporal DBMS, interactive spatio-temporal documents, and future perspectives.

Peer-to-peer (P2P) computing is currently attracting enormous public attention, spurred by the popularity of file-sharing systems such as Napster, Gnutella, and Morpheus. In P2P systems a very large number of autonomous computing nodes, the peers, rely on each other for services. P2P networks are emerging as a new distributed computing paradigm because of their potential to harness the computing power of the hosts composing the network, and because they make their underutilized resources available to each other. Three especially commissioned invited articles appear in this volume: an introduction, and revised versions of the papers presented at the 1st International Workshop on Agents and Peer-to-Peer Computing, AP2PC 2002, held in Bologna, Italy in July 2002. The book is organized into topical sections on peer-to-peer services, discovery and delivery of trustworthy services, and search and cooperation in peer-to-peer agent systems.

This volume contains the lecture notes of the 10th Reasoning Web Summer School 2014, held in Athens, Greece, in September 2014. In 2014, the lecture program of the Reasoning Web introduces students to recent advances in big data aspects of semantic web and linked data, and the fundamentals of reasoning techniques that can be used to tackle big data applications.

This introductory textbook teaches the simple development of geospatial applications based on the principles and software tools of geospatial data science. It introduces a new generation of geospatial technologies that have emerged from the development of the Semantic Web and the linked data paradigm, and shows how data scientists can use them to build environmental applications easily. Geospatial data science is the science of collecting, organizing, analyzing, and visualizing geospatial data. Since around 2010, there has been extensive work in the area of geospatial data science using semantic technologies and linked data, from researchers in the areas of the Semantic Web, Geospatial Databases and Geoinformatics. The main results of this research have been the publication of the OGC standard GeoSPARQL and the implementation of a number of linked data tools supporting this standard. Up to now, there has been no textbook that enables someone to teach this material to undergraduate or graduate students. The material of the book is developed in a tutorial style and it is appropriate for an introductory course on the subject. This can be an advanced undergraduate course or a graduate course offered by Computer Science or GIS faculty. It is a hands-on approach and every chapter contains exercises that help students master the material. The book is accompanied by a Web site where solutions to some of the exercises are given together with supplementary material such as datasets and code. Most of the material in the book has been tried in the "Knowledge Technologies" course taught by the first author in the Department of Informatics and Telecommunications of the National and Kapodistrian University of Athens since 2012.