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The topological structure of RDF graphs inherently differs from other types of graphs, like social graphs, due to the pervasive existence of hierarchical relations (TBox), which complement transversal relations (ABox). Graph measures capture such particularities through descriptive statistics. Besides the classical set of measures established in the field of network analysis, such as size and volume of the graph or the type of degree distribution of its vertices, there has been some effort to define measures that capture some of the aforementioned particularities RDF graphs adhere to. However, some of them are redundant, computationally expensive, and not meaningful enough to describe RDF graphs. In particular, it is not clear which of them are efficient metrics to capture specific distinguishing characteristics of datasets in different knowledge domains (e.g., Cross Domain vs. Linguistics). In this work, we address the problem of identifying a minimal set of measures that is efficient, essential (non-redundant), and meaningful. Based on 54 measures and a sample of 280 graphs of nine knowledge domains from the Linked Open Data Cloud, we identify an essential set of 13 measures, having the capacity to describe graphs concisely. These measures have the capacity to present the topological structures and differences of datasets in established knowledge domains.

PURPOSE OF THE STUDY The postoperative outcomes of total hip replacement and hemiarthroplasty after femoral neck fractures in elderly patients were analysed to determine general and local complications as well as morbidity and mortality rates in order to detect risk profiles and assess the best individual treatment option. MATERIALS AND METHODS One hundred sixty-one femoral neck fractures among patients aged ≥ 65 years treated with cemented hemiarthroplasty (HA) or uncemented total hip arthroplasty (THA) between January 2005 and October 2013 were evaluated. In the presence of articular pathologies as well as a fracture type Garden III or IV, the indication for joint replacement was given. Criteria for performing hemiarthroplasty were previously limited mobility. Freely and fully mobilised patients and patients with manifested osteoarthritis received a cementless THA. A comparison of the observed complications was made, differentiating between general and surgery-specific hip-related complications. Furthermore, the mortality rates were analysed in relation to the respective surgical treatment. RESULTS Seventy cemented HA and ninety-one uncemented THA were performed. There was a high complication rate of approximately 19% in both surgical intervention groups. The patients were more likely to develop general complications (HA 12.8%; THA 10.8%) even though cardiopulmonary complications occurred more frequently in the cemented HA group. Four patients died after cemented hemiarthroplasty due to thromboembolic events (5.7% mortality rate), whereas no deaths occurred after total hip replacement. Surgery-specific complications rates were 7.8% in THA and 5.7% in HA patients. CONCLUSIONS THA in eldery patients with femoral neck fractures is associated with a higher complication rate, mostly of general medical entity. After cemented HA, our study reveals a high mortality rate due to thromboembolic events. For patients with multimorbidity in particular, these findings therefore suggest that uncemented THA should be considered to prevent lethal complications. Key words: femoral neck fracture; total hip arthroplasty; hemiarthroplasty; complications.

Contains fulltext : 197733.pdf (Publisher’s version ) (Open Access) 32 p.

In the context of the EU FP7 DURAARK project (2013–2016), inter-disciplinary methods, technologies and tools have been researched and devel‐oped, that support the Long Term Preservation of semantically enriched digitalrepresentations of built structures. The results of the research efforts includeapproaches of semi-automatically deriving building models from point cloud datasets acquired from laser scans and the integration and overlay of such represen‐tations with explicit Building Information Models (BIM). We introduce novelways for the further semantic enrichment of such hybrid building models withcontextual data and vocabularies from external resources using Linked Data (LD)and the recognition relevant features and building components. A special focusof the research reported here lies on strategies and policies for their long termarchival, information retrieval based on rich semantic metadata and the use ofsuch archival systems in research and commercial scenarios. We introduce a setof prototypical, open-source tools implementing these features that have beenintegrated into a modular preservation framework called the “DURAARK Work‐bench”.

In this paper we present yourHistory: a Facebook application that aims to generate a tailor-made, personalized timeline of historic events, by matching a semantically enriched Facebook profile to a pool of candidate historic events extracted from DBPedia. Two aspects are central to our application: (i) semantic linking technologies backed by rich open web knowledge bases for generating semantically enriched user profiles, and (ii) semantic relatedness metrics for ranking historic events to user profiles. This paper describes the development of a Facebook application that aims to be engaging for users, whilst at the same time being a source for data that can be applied to evaluating or improving the application. We describe our Wikipedia-based semantic relatedness metric for event ranking, but also the restrictions and constraints concerning privacy-sensitive and ethical matters, around data storage and user consent. Finally, we reflect on how this type of user data can be applied for evaluating or improving both the semantic linking and event ranking methods in future work.

Research in technology-enhanced learning (TEL) throughout the last decade has largely focused on sharing and reusing educational resources and data. This effort has led to a fragmented landscape of competing metadata schemas, such as IEEE LOM or ADL SCORM, and interface mechanisms, such as OAI-PMH, SQI and REST-ful services in general. More recently, semantic technologies were taken into account to improve interoperability. However, so far Web-scale integration of resources is not facilitated, mainly due to the lack of take-up of shared principles, datasets and schemas. On the other hand, the Linked Data approach has emerged as the de facto standard for sharing data on the Web and is fundamentally based on established W3C standards. This paper presents results of the European Commission-funded project mEducator, which exploits Linked Data principles for (1) semantic integration and (2) social interconnecting of educational data, resources and actors. We describe a general approach to exploit the wealth of already existing educational data on the Web by allowing its exposure as Linked Data and by taking into account automated enrichment and interlinking techniques to provide a rich and well-interlinked graph for the educational domain. Additionally, the paper presents an evaluation of our work with respect to a set of socio-semantic dimensions. Experimental results demonstrate improved interoperability and retrievability of the resulting resource descriptions as part of an interlinked resource graph.

The social web paradigm has modified the way people behave on the Web. Amongst the many consequences of this change the amount of online resources directly produced and shared by users has increased considerably. In this scenario the importance of methods to evaluate the educational relevance of the resources raises up. In this poster we propose an approach based on recent advancements of Linked Open Data.

A crucial requirement in the web of data is to describe datasets to facilitate acess, reuse, and interlinking. The mEducator project, a best practice netwrok on medical content sharing and repurposing has developed an RDF schema that departures from current learning metadata standards by adopting linked data principles.

mEducator 3.0 is a content sharing approach for medical education, based on Linked Data principles. Through standardization, it enables sharing and discovery of medical information. Overall the mEducator project seeks to address the following two different approaches, mEducator 2.0, based on web 2.0 and ad-hoc Application Programmers Interfaces (APIs), and mEducator 3.0, which builds upon a collection of Semantic Web Services that federate existing sources of medical and Technology Enhanced Learning (TEL) data. The semantic mEducator 3.0 approach It has a number of different instantiations, allowing flexibility and choice. At present these comprise of a standalone social web-based instantiation (MetaMorphosis+) and instantiations integrated with Drupal, Moodle and OpenLabyrinth systems. This paper presents the evaluation results of the mEducator 3.0 Linked Data based environment for sharing medical educational resources and focuses on metadata enrichment, conformance to the requirements and technical performance (of the MetaMorphosis+ and Drupal instantiations).

Past research aiming at interoperability within the Technology- Enhanced Learning (TEL) field has led to a fragmented landscape of competing metadata schemas and interface mechanisms. So far, Web-scale integration of resources is not facilitated, mainly due to the lack of take-up of shared principles, datasets and schemas. On the other hand, the Linked Data approach has emerged as the de-facto standard for sharing data on the Web. We propose MetaMorphosis+, a social educational application which adopts a general approach to exploit existing TEL data on the Web by allowing its exposure as Linked Data and by taking into account automated enrichment and interlinking techniques to provide rich and well-interlinked data for the educational domain.

The two fundamental aims of managing educational resources are to enable resources to be reusable and interoperable and to enable Web-scale sharing of resources across learning communities. Currently, a variety of approaches have been proposed to expose and manage educational resources and their metadata on the Web. These are usually based on heterogeneous metadata standards and schemas, such as IEEE LOM or ADL SCORM, and diverse repository interfaces such as OAI-PMH or SQI. Also, there is still a lack of usage of controlled vocabularies and available data sets that could replace the widespread use of unstructured text for describing resources. On the other hand, the Linked Data approach has proven that it offers a set of successful principles that have the potential to alleviate the aforementioned issues. In this paper, we introduce an architecture and prototype which is fundamentally based on (a) Linked Data principles and (b) Service-orientation to resolve the integration issues for sharing educational resources.

The existence of non-interoperable metadata schemas and limited use of shared vocabularies means that retrieving and processing educational resources across the Web represents a challenge. The emerging Linked Data paradigm has provided the tools and methods to share and expose metadata in a more unified and well interlinked manner, permitting both humans and machines to process Web data. The availability of vast amounts of RDF-based Linked Data is offering a worthwhile alternative to the isolated and heterogeneous data silos which previously dominated the Web. In the ECfunded project mEducator a standardised approach is proposed to describing and exposing medical educational resources. In this paper are described firstly the design considerations, and conceptual model upon which mEducator 's metadata scheme approach was based. Afterwards, follows the description of the serialization of the scheme in RDF/XML, and in turn follows an example showing how medical educational resources are exposed on the Web using an RDF endpoint, and discuss the potential advantages of this approach.

Bisher existiert noch keine umfassende und gesamtheitliche Analyse der Softwareentwicklungsprozesse in der speziellen Domäne der Open Source Software (OSS) Entwicklung. Da eine fundierte Identifikation und eine formalisierte Beschreibung dieser Prozesse eine essentielle Bedingung für die weitere wissenschaftliche Auseinandersetzung mit dieser Thematik darstellt, beschreibt dieser Bericht basierend auf Modellierungselementen der UML die typischen Entwicklunsgprozesse und Prozessentitäten (Rollen, Artefakte, Softwarewerkzeuge) der OSS-Entwicklung. Dieses deskriptive Modell basiert auf der Durchführung vergleichender Fallstudien einiger OSS-Projekte und einem anschließenden Generalisierungprozess, welcher es ermöglichte, die verallgemeinerbaren OSSEntwicklungsprozesse formalisiert zu beschreiben. Basierend auf einem gemeinsamen Metamodell werden die identifizierten Entitäten dargestellt und anschließend alle generalisierten Prozesse detailliert beschrieben und modelliert. Diese Prozessdarstellungen unterteilen die Prozesse in Entwicklungsprozesse, Managementprozesse und infrastrukturelle Prozesse. Während die Entwicklungsprozesse die typischen Aktivitäten der schrittweisen OSS-Verbesserung und der Entwicklung peripherer Artifakte beinhalten, umfassen die Management- und die Infrastrukturprozesse, die sekundäre Prozesse, welche dazu dienen, die Rahmenbedingungen der Entwicklungsprozesse zu schaffen und zu verbessern.