Power converter with power factor adjusting means

US6987676; US6987676 B2; US6987676B2; US6,987,676; US 6,987,676 B2; 6987676; Appl. No. 10/704,623US2004-2005 > Other Outputs > Patents grantedVersion of Recor

Power converter with power factor adjusting means

US6987676; US6987676 B2; US6987676B2; US6,987,676; US 6,987,676 B2; 6987676; Appl. No. 10/704,623USVersion of Recor

Metadata Design of a Content Management System for Music Virtual Learning Environment

Virtual Learning Environment (VLE) uncovers a new learning space for students to start their learning in multidisciplinary subjects and provides an enormous storage for different types of learning materials. This brings not only the ease and flexibility to our learning, but also the challenges in organizing, managing, and controlling of information which is indispensable to the design of an effective online learning system. In particular, Music Information Retrieval (MIR) is an interdisciplinary science on the process of retrieving information from music related resources. Due to the unique application characteristics and various forms of music, appropriate design and application of metadata plays an important role for the MIR in such a Content Management System (CMS) as it would affect the comprehensiveness and effectiveness of the music information retrieval process. In this paper, the authors propose their ontology-based metadata scheme to address such requirements of a music VLE, based on the Dublin Core with modifications according to specific nature of the music learning materials. The metadata design of music resources aims to support students' daily music learning by providing instant and appropriate learning materials which enables cross-collection searching and enhances the sustainability of the contents over time

Effect of temperature gradient on the development of beta phase polypropylene in dynamically vulcanized PP/EPDM blends

Different sample thicknesses were adopted to investigate the effect of temperature gradient on the development of beta phase polypropylene (PP) in the compression-molded dynamically vulcanized thermoplastic elastomers (TPVs) based on PP/ethylene-propylene-diene rubber blend. Differential scanning calorimetry and wide-angle X-ray diffraction were employed to study the melting behavior and crystalline structures. The results indicated that the content of beta phase increased with the sample thickness of TPV increasing, while the total crystallinity of PP almost kept constant. The simulation of the temperature field showed that there was a temperature gradient along the direction of sample thickness, and the strength of the temperature gradient increased with the thickness of TPV increasing. The reason for the change of beta phase content was found to lie in the reduction of the entropy in the temperature gradient field, which was a result from the decrease of the molecular chain conformation