@article {723,
	title = {A Fine-grained Social Network Recommender System},
	journal = {Social Network Analysis and Mining},
	volume = {10},
	year = {2020},
	abstract = {Recommender systems have greatly evolved in recent years and have become an integral part of the Web. From e-commerce sites to mobile apps, our daily routine revolves around a series of {\textquotedblleft}small{\textquotedblright} decisions that are influenced by such recommendations. In a similar manner, online social networks recommend only a subset of the massive amount of content published by a user{\textquoteright}s friends. However, the prevalent approach for the content selection process in such systems is driven by the amount of interaction between the user and the friend who published the content. As a result, content of interest is often lost due to weak social ties. In this paper, we present a fine-grained recommender system for social ecosystems, designed to recommend media content (e.g., music videos, online clips) published by the user{\textquoteright}s friends. The system design was driven by the findings of our qualitative user study that explored the value and requirements of a recommendation component within a social network. The core idea behind the proposed approach was to leverage the abundance of preexisting information in each user{\textquoteright}s account for creating interest profiles, to calculate similarity scores at a fine-grained level for each friend. The intuition behind the proposed method was to find consistent ways to obtain information representations that can identify overlapping interests in very specific sub-categories (e.g., two users{\textquoteright} music preferences may only coincide on hard rock). While the system is intended as a component of the social networking service, we developed a proof-of-concept implementation for Facebook and explored the effectiveness of our underlying mechanisms for content analysis. Our experimental evaluation demonstrates the effectiveness of our approach, as the recommended content of interest was both overlooked by the existing Facebook engine and not contained in the users{\textquoteright} Facebook News Feed. We also conducted a user study for exploring the usability aspects of the prototype and found that it offers functionality that could significantly improve user experience in popular services.},
	keywords = {Content Analysis, Interest Profiles, Recommender Systems, Social Networks, Usability},
	issn = {1869-5469},
	doi = {10.1007/s13278-019-0621-7},
	author = {Markos Aivazoglou and Antonios Roussos and Dionisis Margaris and Costas Vassilakis and Sotiris Ioannidis and Jason Polakis and Dimitris Spiliotopoulos}
}
@conference {570,
	title = {Constructing Subsumption Hierarchies of Web Queries},
	booktitle = {Proceedings of the International Workshop on Dataset PROFIling and fEderated Search for Linked Data (PROFILES @ ESWC)},
	year = {2015},
	month = {May},
	address = {Portoroz, Slovenia},
	author = {Alexander Prohaska and Christos Tryfonopoulos and Georgiana Ifrim}
}
@article {582,
	title = {Distributed Large-Scale Information Filtering},
	journal = {Transactions on Large-Scale Data- and Knowledge-Centered Systems (TLDKS)},
	volume = {13},
	year = {2014},
	pages = {91{\textendash}122},
	abstract = {We study the problem of distributed resource sharing in peer-to-peer networks and focus on the problem of information filter- ing. In our setting, subscriptions and publications are specified using an expressive attribute-value representation that supports both the Boolean and Vector Space models. We use an extension of the distributed hash table Chord to organise the nodes and store user subscriptions, and utilise efficient publication protocols that keep the network traffic and latency low at filtering time. To verify our approach, we evaluate the proposed protocols experimentally using thousands of nodes, millions of user subscriptions, and two different real-life corpora. We also study three important facets of the load-balancing problem in such a scenario and present a novel algorithm that manages to distribute the load evenly among the nodes. Our results show that the designed protocols are scalable and efficient: they achieve expressive information filtering functionality with low message traffic and latency.},
	keywords = {distributed hash tables, Information management, publish/subscribe},
	author = {Christos Tryfonopoulos and Stratos Idreos and Manolis Koubarakis and Paraskevi Raftopoulou}
}
@proceedings {DBLP:conf/edbt/2014,
	title = {Proceedings of the 17th International Conference on Extending Database Technology, EDBT 2014, Athens, Greece, March 24-28, 2014},
	year = {2014},
	publisher = {OpenProceedings.org},
	url = {http://openproceedings.org/html/pages/2014_edbt.html},
	editor = {Sihem Amer-Yahia and Vassilis Christophides and Anastasios Kementsietsidis and Minos N. Garofalakis and Stratos Idreos and Vincent Leroy}
}
@article {dix2010b,
	title = {From the web of data to a world of action},
	journal = {Journal of Web Semantics},
	volume = {8 issue 4},
	year = {2010},
	pages = {394-408},
	abstract = {This paper takes as its premise that the web is a place of action, not just information, and that the purpose of global data is to serve human needs. The paper presents several component technologies, which together work towards a vision where many small micro-applications can be threaded together using automated assistance to enable a unified and rich interaction. These technologies include data detector technology to enable any text to become a start point of semantic interaction; annotations for web-based services so that they can link data to potential actions; spreading activation over personal ontologies, to allow modelling of context; algorithms for automatically inferring {\textquoteleft}typing{\textquoteright} of web-form input data based on previous user inputs; and early work on inferring task structures from action traces. Some of these have already been integrated within an experimental web-based (extended) bookmarking tool, Snip!t, and a prototype desktop application On Time, and the paper discusses how the components could be more fully, yet more openly, linked in terms of both architecture and interaction. As well as contributing to the goal of an action and activity-focused web, the work also exposes a number of broader issues, theoretical, practical, social and economic, for the Semantic Web.},
	doi = {10.1016/j.websem.2010.04.007},
	author = {Alan Dix and Giorgos Lepouras and Akrivi Katifori and Costas Vassilakis and Tiziana Catarci and Antonella Poggi and Yannis Ioannidis and Miguel Morae and I. Daradimos and Nazihah Md.Akima and Shah Rukh Humayound and Fabio Terella}
}
@conference {Katifori2008a1,
	title = {Personal Ontology Creation and Visualization for a Personal Interaction Management System},
	booktitle = {Proceedings of PIM, CHI 2008},
	year = {2008},
	month = {4},
	abstract = {Ontologies offer a flexible and expressive layer of abstraction, very useful for capturing the semantics of information repositories and facilitating their retrieval either by the user or by the system to support user tasks. This work presents an ontology-based user profiler, in the context of a Personal Interaction Management System (PIMS). The profiler, based on an ontology of the users? domain, enables them to create their personal ontology by initially choosing one of the available template ontologies as a starting point, which they subsequently populate and customize. The profiler employs a web interface which allows users to populate their personal ontology through forms, hiding ontology complexities and peculiarities. Forms are dynamically generated through ontology views, which are specified by ontology designers.},
	author = {Akrivi Katifori and Costas Vassilakis and I. Daradimos and Giorgos Lepouras and Yannis Ioannidis and Alan Dix and Antonella Poggi and Tiziana Catarci}
}
@conference {559,
	title = {Distributed Evaluation of Continuous Equi-join Queries over Large Structured Overlay Networks},
	booktitle = {Proceedings of the 22nd International Conference on Data Engineering (ICDE)},
	year = {2006},
	month = {April},
	address = {Atlanda, USA},
	author = {Stratos Idreos and Christos Tryfonopoulos and Manolis Koubarakis}
}
@conference {547,
	title = {LibraRing: An Architecture for Distributed Digital Libraries Based on DHTs},
	booktitle = {Proceedings of the 9th European Conference on Research and Advanced Technology for Digital Libraries (ECDL)},
	year = {2005},
	month = {September},
	address = {Vienna, Austria},
	author = {Christos Tryfonopoulos and Stratos Idreos and Manolis Koubarakis}
}
@conference {542,
	title = {Publish/Subscribe Functionalities for Future Digital Libraries using Structured Overlay Networks},
	booktitle = {Proceedings of the 8th International Workshop of the DELOS Network of Excellence on Digital Libraries on Future Digital Library Management Systems},
	year = {2005},
	month = {March},
	address = {Schloss Dagstuhl, Germany},
	author = {Christos Tryfonopoulos and Stratos Idreos and Manolis Koubarakis}
}
@conference {573,
	title = {Publish/Subscribe Functionality in IR Environments using Structured Overlay Networks},
	booktitle = {Proceedings of the 28th Annual International ACM SIGIR Conference},
	year = {2005},
	month = {August},
	address = {Salvador, Brazil},
	author = {Christos Tryfonopoulos and Stratos Idreos and Manolis Koubarakis}
}
@conference {576,
	title = {P2P-DIET: An Extensible P2P Service that Unifies Ad-hoc and Continuous Querying in Super-Peer Networks},
	booktitle = {Proceedings of the ACM SIGMOD Conference},
	year = {2004},
	month = {June},
	address = {Paris, France},
	author = {Stratos Idreos and Manolis Koubarakis and Christos Tryfonopoulos}
}
@conference {551,
	title = {P2P-DIET: One-Time and Continuous Queries in Super-Peer Networks},
	booktitle = {Proceedings of the 9th International Conference on Extending Database Technology (EDBT)},
	year = {2004},
	month = {March},
	address = {Heraklion, Greece},
	author = {Stratos Idreos and Manolis Koubarakis and Christos Tryfonopoulos}
}
@conference {567,
	title = {Query Processing in Super-Peer Networks with Languages Based on Information Retrieval: the P2P-DIET Approach},
	booktitle = {Proceedings of the International Workshop on Peer-to-peer Computing and Databases (P2P\&DB @ EDBT)},
	year = {2004},
	month = {March},
	address = {Herakion, Greece},
	author = {Stratos Idreos and Christos Tryfonopoulos and Manolis Koubarakis and Yannis Drougas}
}
@article {577,
	title = {Selective Information Dissemination in P2P Networks: Problems and Solutions},
	journal = {SIGMOD Record, Special Issue on Peer-to-Peer Data Management},
	volume = {32},
	year = {2003},
	pages = {71-76},
	author = {Manolis Koubarakis and Christos Tryfonopoulos and Stratos Idreos and Yannis Drougas},
	editor = {Karl Aberer}
}
