Choosing a higher education course at university is not an easy task for students. A wide range of courses are offered by the individual universities whose delivery mode and entry requirements differ. A personalized recommendation system can be an effective way of suggesting the relevant courses to the prospective students. This paper introduces a novel approach that personalizes course recommendations that will match the individual needs of users. The proposed approach developed a framework of an ontologybased hybrid-filtering system called the ontology-based personalized course recommendation (OPCR). This approach aims to integrate the information from multiple sources based on the hierarchical ontology similarity with a view to enhancing the efficiency and the user satisfaction and to provide students with appropriate recommendations. The OPCR combines collaborative-based filtering with content-based filtering. It also considers familiar related concepts that are evident in the profiles of both the student and the course, determining the similarity between them. Furthermore, OPCR uses an ontology mapping technique, recommending jobs that will be available following the completion of each course. This method can enable students to gain a comprehensive knowledge of courses based on their relevance, using dynamic ontology mapping to link the course profiles and student profiles with job profiles. Results show that a filtering algorithm that uses hierarchically related concepts produces better outcomes compared to a filtering method that considers only keyword similarity. In addition, the quality of the recommendations is improved when the ontology similarity between the items' and the users' profiles were utilized. This approach, using a dynamic ontology mapping, is flexible and can be adapted to different domains. The proposed framework can be used to filter the items for both postgraduate courses and items from other domains.

Traditional transparent conducting oxides (TCOs) have been widely used for various optoelectronic applications, but have the trade-off between conductivity and transmittance. Recently, perovskite oxides, with structural and chemical stability, have exhibited excellent physical properties as new TCOs. We focus on SrVO3-based perovskites with a high carrier concentration and BaSnO3-based perovskites with a high mobility for n-type TCOs. In addition, p-type perovskites are discussed, which can serve as potential future options to couple with n-type perovskites to design full perovskite based devices.

Undoped and Ce-doped Ba0.5Sr0.5TiO3 (BST) thin films were prepared by pulsed-laser deposition onto a Nb-doped SrTiO3 (STON) substrate. The Ce concentration, ranging from 0.5 to 1.0 at.%, was found to have a strong influence on the electric properties of films at room temperature. We find that, with a positively biased Pt electrode, the leakage current controlled by BST/STON interface can be described by a space-charge-limited-current model. When the Pt electrode is negatively biased, the leakage current controlled by the BST/Pt interface can be explained by the Schottky emission mechanism. In both cases the Ce-doped BST thin films exhibited a lower leakage current (1.2 × 10−4 and 5.0 × 10−5 versus 3.4 × 10−2 A cm−2 at 450 kV cm−1; 4.0 × 10−4 and 4.0 × 10−5 versus 6.2 × 10−3 A cm−2 at −450 kV cm−1) than undoped BST films. The reduction of the leakage current is ascribed to the effect of acceptor Ce3+ doping, determined by x-ray photoelectron spectroscopy measurement.

Ba 0.5 Sr 0.5 TiO 3 (BST) thin films are among the best-known ferroelectric and dielectric materials. Ce-doped BST films have been fabricated by pulsed laser deposition in order to enhance their dielectric properties. X-ray diffraction, atomic force microscopy, and Raman spectroscopy have been used to study variations of crystal structure, surface morphologies, and phase stability of Ce-doped BST films, respectively. A strong influence of Ce doping on the properties of the BST films has been observed. First, a small amount of Ce dopant makes easy epitaxial growth of a BST film with a smooth surface on a MgO substrate. Second, residual stress in a BST film on a MgO substrate can be reduced by Ce doping, as demonstrated by the blueshift of phonon peaks in Raman spectroscopy.