Building a Usable and Accessible Semantic Web Interaction Platform

Semantic Web applications take off is being slower than expected, at least with respect to “real-world” applications and users. One of the main reasons for this lack of adoption is that most Semantic Web user interfaces are still immature from the usability and accessibility points of view. This is due to the novelty of these technologies, but this also motivates the exploration of alternative interaction paradigms, different from the “traditional” Web or Desktop applications ones. Our proposal is realized in the Rhizomer platform, which explores the possibilities of the object–action interaction paradigm at the Web scale. This paradigm is well suited for heterogeneous resource spaces such as those common in the Semantic Web. Resources, described by metadata, correspond to the objects in the paradigm. Semantic web services, which are dynamically associated to these objects, correspond to the actions. The platform is being put into practice in the context of a research project in order to build an open application for media distribution based on Semantic Web technologies. Moreover, its usability and accessibility have been evaluated in this real setting and compared to similar systems.     

The semantic web as a newspaper media convergence facilitator

Newspapers are evolving and this causes great changes in how newspapers reach their consumers, but also in how newspapers work internally. Advanced computerised support is needed in order to cope with the new needs, which require that machines are aware of a greater part of the underlying semantics. Ontologies and Semantic Web technologies are clear candidates for web-wide semantics. However, newspapers have made great investments in their current news management systems and their wish is to undertake a smooth transition. Our proposal is to build an ontological framework based on existing journalism and multimedia standards. These standards are based on XML technologies. Therefore, we have developed a generic XML Schema to OWL mapping, complemented with an XML to RDF one. Together, they allow reusing existing metadata that, once in a semantic space, facilitates data integration, news management and retrieval. The resulting ontological framework is being applied in the Diari Segre Media Group¹, which produces press, radio and television content.     

Low-Temperature Fabrication of Oxide Composites for Solid-Oxide Fuel Cells

Composites of yttria-stabilized zirconia (YSZ) with Sr-doped LaCrO₃ (LSC) and Sr-doped LaMnO₃ (LSM) were prepared by impregnation of a porous YSZ matrix with aqueous solutions of the appropriate metal salts, followed by sintering to various temperatures. XRD measurements showed that perovskite phases formed after sintering at 1073 K, a temperature well below that at which solid-state reactions with YSZ occur. The conductivities of the LSC–YSZ and LSM–YSZ composites prepared in this way were maximized at a sintering temperature of 1373 K for LSC–YSZ and 1523 K for LSM–YSZ, although reasonable conductivities were achieved at much lower temperatures. The conductivities of the two composites increased much more rapidly with the content of the conductive oxide than has been found with conventional composites formed by mixing and sintering the oxide powders. The implications for using this approach to develop novel electrodes for SOFC applications are discussed.     

Characterization of the human iris spectral reflectance with a multispectral imaging system

We present a multispectral system developed and optimized for measurement of the spectral reflectance and the color of the human iris. We tested several sets of filters as acquisition channels, analyzed different reconstruction algorithms, and used different samples as training sets. The results obtained show that a conventional three-channel color camera (RGB) was enough to reconstruct the analyzed reflectances with high accuracy, obtaining averaged color differences of around 2-3 CIEDE2000 units and root mean square errors of around 0.01. The device developed was used to characterize 100 real irises corresponding to 50 subjects, 68 prostheses used in clinical practice, and 17 cosmetic colored contact lenses.     

Consequence analysis to determine damage to buildings from vapour cloud explosions using characteristic curves

The objective of this paper is to propose a methodology to estimate the consequences to buildings from the pressure wave caused by unconfined vapour cloud explosions (VCEs). This methodology is based on the use of characteristic overpressure-impulse-distance curves, shown in a previous paper [F. Diaz Alonso, E. Gonzalez Ferradas, J.F. Sanchez Perez, A. Mi?ana Aznar, J. Ruiz Gimeno, J. Martinez Alonso, Characteristic overpressure-impulse-distance curves for vapour cloud, explosions using the TNO Multi-Energy model, J. Hazard. Mater. A137 (2006) 734-741]. They allow the overpressure and impulse at each distance from the explosion to be determined. Since they can be combined with damage criteria (such as those shown by the PROBIT equations), they can be used to perform consequence analysis as the damage is shown in the same diagram as the overpressure, impulse and distance. Since damages suffered by buildings usually affect people inside, it is important to take them into account when performing consequence analysis. This is done in this paper, where diagrams and equations are presented to determine minor damage to buildings (broken windows, displacement of doors and window frames, tile displacement, etc.), major structural damage (cracks in walls, collapse of some walls) and collapse (the damage is so extensive that the building is partially or totally demolished). This paper completes the consequence analysis to humans outdoors shown by F.D. Alonso et al. [F. Diaz Alonso, E. Gonzalez Ferradas, T. Jimenez Sanchez, A. Mi?ana Aznar, J. Ruiz Gimeno, J. Martinez Alonso, Consequence analysis to determine the damage to humans from vapour cloud explosions using characteristic curves, J. Hazard. Mater., in press].     

Determination of the solid-water distribution coefficient (Kd) for pharmaceuticals, estrogens and musk fragrances in digested sludge

This work determined the solid-water distribution coefficient (K(d)) and the organic carbon normalized distribution coefficient (K(oc)) of several pharmaceuticals (carbamazepine, ibuprofen, naproxen, diclofenac, iopromide, sulfamethoxazole and roxithromycin), three estrogens (estrone, 17beta-estradiol and 17alpha-ethinylestradiol) and two musk fragrances (HHCB and AHTN) in digested sludge. These sorption coefficients can be used to evaluate the fate of these substances during sludge treatment, thus avoiding the expensive and time-consuming analysis in the sludge phase. For determining the K(d) and K(oc) values of the target compounds in digested sludge, their concentrations were measured in the aqueous and solid phase of the effluent of an anaerobic digestion pilot plant run at several operational conditions. The results obtained were compared with the values modelled by using simple K(ow) approaches. The resulting log K(d) values ranged between 3.5 and 4.4 for the two musk fragrances (log K(oc) of 4.5-6.0), between 2.1 and 2.9 for estrogens (log K(oc) of 2.9-4.2) and between 0.8 and 1.9 for the remaining pharmaceuticals (log K(oc) of 1.8-3.5). These values are in the same range as those reported in the literature for primary and secondary sludge and no significant influence of the anaerobic digestion operational conditions was observed. For most compounds, the modelled K(oc) were close or within the lower range of the experimentally determined K(oc). Major deviations of the modelled K(oc) values were found for iopromide, sulfamethoxazole and roxithromycin, which were 1-3 orders of magnitude lower than the measured values.     

Direct imaging of lattice atoms and topological defects in graphene membranes

We present a transmission electron microscopy investigation of graphene membranes, crystalline foils with a thickness of only 1 atom. By using aberration-correction in combination with a monochromator, 1-A resolution is achieved at an acceleration voltage of only 80 kV. The low voltage is crucial for the stability of these membranes. As a result, every individual carbon atom in the field of view is detected and resolved. We observe a highly crystalline lattice along with occasional point defects. The formation and annealing of Stone-Wales defects is observed in situ. Multiple five- and seven-membered rings appear exclusively in combinations that avoid dislocations and disclinations, in contrast to previous observations on highly curved (tube- or fullerene-like) graphene surfaces.     

Wild boar hair (Sus scrofa) as a non-invasive indicator of mercury pollution

This paper investigates the usefulness of wild boar (Sus scrofa) hair as a non-invasive indicator of mercury pollution. Samples were collected in two hunting seasons (1998/1999 and 1999/2000) by hunters from four differently polluted regions of Poland. Mercury content was determined by AAS methods. Different washing procedures were compared. De-ionised water was found to be suitable for the removal of exogenous mercury sources in hair analysis. Metal distribution along hair was analysed. It was found that problems arising from differences in distribution of metal along a single hair strand as well as differences in the hair colour can be eliminated through the careful homogenisation of the samples before analysis. The influences of physiological, ecological and environmental factors that might significantly affect the obtained results (age, gender, season, location of habitat and diet of the sampled animals) were estimated and taken into account. The present study revealed that female hair contained a higher amount of mercury than male hair. Moreover the highest mercury content was found in young individuals between 1 and 2 years of age. A positive correlation of the present results with environmental data taken from the State Offices showed an influence of environmental pollution on the mercury level in wild boar hair.     

Using geometric constraints through parallelepipeds for calibration and 3D modeling

This paper concerns the incorporation of geometric information in camera calibration and 3D modeling. Using geometric constraints enables more stable results and allows us to perform tasks with fewer images. Our approach is motivated and developed within a framework of semi-automatic 3D modeling, where the user defines geometric primitives and constraints between them. In this paper, first a duality that exists between the shape parameters of a parallelepiped and the intrinsic parameters of a camera is described. Then, a factorization-based algorithm exploiting this relation is developed. Using images of parallelepipeds, it allows us to simultaneously calibrate cameras, recover shapes of parallelepipeds, and estimate the relative pose of all entities. Besides geometric constraints expressed via parallelepipeds, our approach simultaneously takes into account the usual self-calibration constraints on cameras. The proposed algorithm is completed by a study of the singular cases of the calibration method. A complete method for the reconstruction of scene primitives that are not modeled by parallelepipeds is also briefly described. The proposed methods are validated by various experiments with real and simulated data, for single-view as well as multiview cases.