John G. Breslin

Towards semantically-interlinked online communities

Online community sites have replaced the traditional means of keeping a community informed via libraries and publishing. At present, online communities are islands that are not interlinked. We describe different types of online communities and tools that are currently used to build and support such communities. Ontologies and Semantic Web technologies offer an upgrade path to providing more complex services. Fusing information and inferring links between the various applications and types of information provides relevant insights that make the available information on the Internet more valuable. We present the SIOC ontology which combines terms from vocabularies that already exist with new terms needed to describe the relationships between concepts in the realm of online community sites.

The Future of Social Networks on the Internet: The Need for Semantics

Everyone on the Internet knows the buzzword social networking. Social networking services (SNS) usually offer the same basic functionalities: network of friends listings, person surfing, private messaging etc. With such features, SNSs demonstrate how the Internet continues to better connect people for various social and professional purposes. The fundamental problems with todays SNSs block their potential to access the full range of available content and networked people online. A possible solution is to build semantic social networking into the fabric of the next-generation Internet itself-interconnecting both content and people in meaningful ways. The semantic Web is a useful platform for linking and for performing operations on diverse person-and object-related data gathered from heterogeneous social networking sites. In the other direction, object-centered networks can serve as rich data sources for semantic Web applications.

Optimized transformer design: inclusive of high-frequency effects

Switching circuits, operating at high frequencies, have led to considerable reductions in the size of magnetic components and power supplies. Nonsinusoidal voltage and current waveforms and high-frequency skin and proximity effects contribute to power transformer losses. Traditionally, power transformer design has been based on sinusoidal voltage and current waveforms operating at low frequencies. The physical and electrical properties of the transformer form the basis of a new design methodology while taking full account of the current and voltage waveforms and high-frequency effects. Core selection is based on the optimum throughput of energy with minimum losses. The optimum core is found directly from the following transformer specifications: frequency; power output; and temperature rise. The design methodology is illustrated with a detailed design of a push-pull power converter.

Semantic social network portal for collaborative online communities

Purpose – The motivation for this investigation is to apply social networking features to a semantic network portal, which supports the efforts in enterprise training units to up‐skill the employee in the company, and facilitates the creation and reuse of knowledge in online communities.Design/methodology/approach – The paper provides an overview of an emerging area for work‐related research in the field of knowledge management and collaborative online communities.Findings – The growing number of social network online communities requires a systematic assessment of the application and design of social network technologies, which makes this study relevant and timely.Practical implications – This paper gives guidance in an emerging research area with major implications for online communities and human resources management.Originality/value – Fulfils a need, since a lack of literature in the field is apparent.

Interlinking the Social Web with Semantics

This paper deals with applying semantic Web technologies to the social Web can lead to a social semantic Web, creating a network of interlinked and semantically rich knowledge. One of the most visible trends on the Web is the emergence of social Web sites, which help people create and gather knowledge by simplifying user contributions via blogs, tagging and folksonomies, wikis, podcasts, and online social networks. The social Web has enabled community-based knowledge acquisition.

SIOC: an approach to connect web-based communities

Online communities are islands of people and topics that are not interlinked. Complementary discussions exist on disparate systems but it is currently difficult to exploit the available distributed information. A Semantically Interlinked Online Community (SIOC) can enable efficient information dissemination across communities by creating an ontology that will model concepts identified in discussion methods. Data instances can be accessed from community sites using this ontology, enabling connections between local and remote concept instances, and allowing queries on, or transfer of, the data. By searching on one forum, the ontology and interface will allow users to find information on other forums that use a SIOC-based system architecture. Other uses include cross-site querying, topic-related searches, and the importing of SIOC data into other systems. Fusing information and inferring links among various applications and types of information with SIOC provide relevant insights that make the community information available on the internet more valuable.

Optimizing the AC resistance of multilayer transformer windings with arbitrary current waveforms

AC losses due to nonsinusoidal current waveforms have been found by calculating the losses at harmonic frequencies when the Fourier coefficients are known. An optimized foil or layer thickness in a winding may be found by applying the Fourier analysis over a range of thickness values. This paper presents a new formula for the optimum foil or layer thickness, without the need for Fourier coefficients and calculations at harmonic frequencies. The new formula requires the RMS value of the current waveform and the RMS value of its derivative. It is simple, straightforward and applies to any periodic waveshape.

Aggregated, interoperable and multi-domain user profiles for the social web

User profiling techniques have mostly focused on retrieving and representing a users knowledge, context and interests in order to provide recommendations, personalise search, and build user-adaptive systems. However, building a user profile on a single social network limits the quality and completeness of the profile, especially when interoperability of the profile is key and its reuse on different sites is necessary for providing other types of personalisation. Indeed recent studies have shown that users on the Social Web often use different social networking sites for diverse, and sometimes non-overlapping, purposes and interests. In this paper, we describe our methodology for the automatic creation and aggregation of interoperable and multi-domain user profiles of interests using semantic technologies. Moreover, we propose a user study on different user profiling techniques for social networking websites in general, and for Twitter and Facebook in particular. In this regard, based on the results of our user evaluation, we investigate (i) the accuracy of different methodologies for profiling, (ii) the effect of time decay functions on ranking user interests, and (iii) the benefits of merging different user models using semantic technologies.

Combining RDF Vocabularies for Expert Finding

This paper presents a framework for the reuse and extension of existing, established vocabularies in the Semantic Web. Driven by the primary application of expert finding, we will explore the reuse of vocabularies that have attracted a considerable user community already (FOAF, SIOC, etc.) or are derived from de facto standards used in tools or industrial practice (such as vCard, iCal and Dublin Core). This focus guarantees direct applicability and low entry barriers, unlike when devising a new ontology from scratch. The Web is already populated with several vocabularies which complement each other (but also have considerable overlap) in that they cover a wide range of necessary features to adequately describe the expert finding domain. Little effort has been made so far to identify and compare existing approaches, and to devise best practices on how to use and extend various vocabularies conjointly. It is the goal of the recently started ExpertFinder initiative to fill this gap. In this paper we present the ExpertFinder framework for reuse and extension of existing vocabularies in the Semantic Web. We provide a practical analysis of overlaps and options for combined use and extensions of several existing vocabularies, as well as a proposal for applying rules and other enabling technologies to the expert finding task.

Semantic wikis for personal knowledge management

Wikis are becoming popular knowledge management tools. Analysing knowledge management requirements, we observe that wikis do not fully support structured search and knowledge reuse. We show how Semantic wikis address the requirements and present a general architecture. We introduce our SemperWiki prototype which offers advanced information access and knowledge reuse.