Improving Ontology Recommendation and Reuse in WebCORE by Collaborative Assessments

In this work, we present an extension of CORE [8], a tool for Collaborative Ontology Reuse and Evaluation. The system receives an informal description of a specific semantic domain and determines which ontologies from a repository are the most appropriate to describe the given domain. For this task, the environment is divided into three modules. The first component receives the problem description as a set of terms, and allows the user to refine and enlarge it using WordNet. The second module applies multiple automatic criteria to evaluate the ontologies of the repository, and determines which ones fit best the problem description. A ranked list of ontologies is returned for each criterion, and the lists are combined by means of rank fusion techniques. Finally, the third component uses manual user evaluations in order to incorporate a human, collaborative assessment of the ontologies. The new version of the system incorporates several novelties, such as its implementation as a web application; the incorporation of a NLP module to manage the problem definitions; modifications on the automatic ontology retrieval strategies; and a collaborative framework to find potential relevant terms according to previous user queries. Finally, we present some early experiments on ontology retrieval and evaluation, showing the benefits of our system

Broadband suppression of backscattering at optical frequencies using low permittivity dielectric spheres

The exact suppression of backscattering from rotationally symmetric objects requires dual symmetric materials where ${\epsilon_r} = {\mu_r}$. This prevents their design at many frequency bands, including the optical one, because magnetic materials are not available. Electromagnetically small non-magnetic spheres of large permittivity offer an alternative. They can be tailored to exhibit balanced electric and magnetic dipole polarizabilities, which result in approximate zero backscattering. In this case, the effect is inherently narrowband. Here, we put forward a different alternative that allows broadband functionality: Electromagnetically large spheres made from low permittivity materials. The effect occurs in a parameter regime that approaches the trivial ${\epsilon_r} \to {\mu_r} =1$ case, where approximate duality is met in a weakly wavelength dependence fashion. Despite the low permittivity, the overall scattering response of the spheres is still significant. Radiation patterns from these spheres are shown to be highly directive across an octave spanning band. The effect is analytically and numerically shown using the Mie coefficients.Comment: 6 Figure

Characterization of non-intentional emissions from distributed energy resources up to 500 kHz: A case study in Spain

Narrow Band Power Line Communications (NB-PLC) systems are currently used for smart metering and power quality monitoring as a part of the Smart Grid (SG) concept. However, non-intentional emissions generated by the devices connected to the grid may sometimes disturb the communications and isolate metering equipment. Though some research works have been recently developed to characterize these emissions, most of them have been limited to frequencies below 150 kHz and they are mainly focused on in-house electronic appliances and lightning devices. As NB-PLC can also be allocated in higher frequencies up to 500 kHz, there is still a lack of analysis in this frequency range, especially for emissions from Distributed Energy Resources (DERs). The identification and characterization of the emissions is essential to develop solutions that avoid a negative impact on the proper performance of NB-PLC. In this work, the non-intentional emissions of different types of DERs composing a representative microgrid have been measured in the 35–500 kHz frequency range and analyzed both in time and frequency domains. Different working conditions and coupling and commutation procedures to mains are considered in the analysis. Results are then compared to the limits recommended by regulatory bodies for spurious emissions from communication systems in this frequency band, as no specific limits for DERs have been established. Field measurements show clear differences in the characteristics of non-intentional emissions for different devices, working conditions and coupling procedures and for frequencies below and above 150 kHz. Results of this study demonstrate that a further characterization of the potential emissions from the different types of DERs connected to the grid is required in order to guarantee current and future applications based on NB-PLC.This work has been financially supported in part by the Basque Government (Elkartek program)

Diplomacy and Security Community-Building: EU Crisis Management in the Western Mediterranean

ReviewBook Revie

The ENP and EU-Maghreb relations

This is the author accepted manuscript. The final version is available from Routledge via the ISBN in this recordThe recipients of the southern dimension of the European Neighbourhood Policy (ENP) include a quite distinct grouping of countries, the Maghreb, which can be approached either as a full-fledged regional unit by itself or as a sub-regional setting comprised in the broader regional system of the Middle East and North Africa. The fact that the western part of the Arab world, or northwestern Africa, is constructed and recognised as a distinct geopolitical unit owes much to its intimate historical connection with – and external penetration by – European powers. Besides a similarly mixed Arab-Amazigh ethnic and linguistic background, and an also common Islamic religious identity, what has drawn the borders of the region as an imagined community is a somewhat shared colonial experience under the rule of predominantly France (in the case of the three “central Maghreb” countries, i.e. Morocco, Algeria and Tunisia, as well as Mauritania) and secondarily Italy (Libya) and Spain (parts of Morocco and Western Sahara). For the purposes of geopolitical outlining and labelling, this commonality has prevailed over significant divergences between the concerned countries in terms of their contemporary histories – belonging to the Ottoman Empire, form and length of colonial rule, access to independence –, their economic, social and demographic structures, and their postcolonial political systems. This chapter addresses the questions of what are the structural characteristics of EU-Maghreb relations, and what factors account for these global features as well as bilateral differentiation vis-à- vis each individual country of the region in the framework of the ENP. The different answers provided are broadly connected to the main theoretical approaches in International Relations (IR), namely realism, liberalism and constructivism, incorporating also some insights from international political economy and postcolonialism. The following sections will examine the postcolonial legacies and background of the process of institutionalisation of EU-Maghreb relations; the debate on the degree of interdependence or dependency which can be observed in this relationship from an international political economy perspective; the realist hindrances to liberal region-building and integration between the Maghreb countries; and the allocation of foreign policy roles and bilateral differentiation between them in the context of the ENP. The focus will be placed on Tunisia, Algeria and Morocco, since Mauritania is not included in the geopolitical scope of the ENP, Libya has so far remained outside most of the ENP structures despite being recognised as a potential participant, and the Western Sahara conflict has never been directly targeted by this EU policy