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This paper presents the design and implementation of a 3 kVA three-phase active T-type neutral-point clamped (NPC) inverter with GaN power devices for low-voltage microgrids. The designed inverter is used in a battery-based energy system (BESS) for power conversion optimization in applications to low-voltage microgrids. A modular design method has been developed for the design and implementation of the AT-NPC inverter. Experimental verification has been carried out based on a 3-kW three-phase T-Type NPC gridconnected inverter. FPGA based digital control technique has been developed for the current control of the three-level three-phase grid inverter. A maximum efficiency of 98.49% has been achieved within a load range from 50% to 75%.

Context aware ubiquitous learning is a computer supported learning paradigm for identifying learners' surrounding contextual environment and social presence to provide integrated, interoperable, pervasive, and seamless learning experiences. The objective of context aware ubiquitous learning is to move Web and mobile learning a step further from learning at anytime anywhere to be at the right time and right place with right learning resources and right learning peers. There are many high quality paper submissions from Africa, America, Asia Pacific, and Europe. All submissions received double blind reviews by TPC members or external reviewers. In order to maintain the high quality of the workshop, only 38% of the submissions are accepted for presentation on the workshop. The CAUL workshop organizers would like to express our deepest thankfulness to many individuals and groups who have been contributing to the possibility of the CAUL workshop. First of all, we would like to thank Prof. Jeffrey Tsai who is the SUTC General Co-Chairs, as well as Prof. Laurence T. Yang, and Prof. Jianhua Ma, who are the SUTC Workshop Co-Chairs for their kindly supports to include CAUL workshop to the SUTC. Secondly, we would like to thank the technical program committees and the external reviewers who have provided tremendous valuable expertise and constructive comments to lift the quality of paper reviewing process. Finally, we would like to thank Prof. Kinshuk, who is the Editor-in-Chief of the Journal of Educational Technology & Society (SSCI Indexed) for their partnership of a special issue on "Context-Aware Ubiquitous Learning."