Pusan National University

About: Pusan National University is a education organization based out in Busan, South Korea. It is known for research contribution in the topics: Population & Catalysis. The organization has 24124 authors who have published 45054 publications receiving 819356 citations. The organization is also known as: Busan National University & Pusan University.

Development of Hardware In-the-Loop Simulation System for Testing Operation and Control Functions of Microgrid

Abstract: This paper proposes a hardware in-the-loop simulation (HILS) system as a new method to develop and test control algorithms and operation strategies for a microgrid. The HILS system is composed of a real-time digital simulator (RTDS) for real-time simulation of the microgrid, a prototype microgrid management system (MMS) under test, and a communication emulator for interface between the prototype MMS and the RTDS. The prototype MMS is designed to operate microsources of microgrid and to control power flow at the point of common coupling (PCC) in the grid-connected mode, and voltages and frequency in the islanded mode of the microgrid. The MMS is tested in the grid-connected mode and in the islanded mode, respectively, to show the validation of the proposed HILS system.

Silica grafted imidazolium-based ionic liquids: efficient heterogeneous catalysts for chemical fixation of CO2 to a cyclic carbonate

Abstract: Imidazolium-based ionic liquids with varied alkyl chain lengths bearing different anions (Cl−, Br− and I−) were synthesized and immobilized onto the commercial silica surface (IMIS). These heterogeneous catalysts exhibited high catalytic activities and selectivities in the cycloaddition of carbon dioxide to allyl glycidyl ether (AGE). The immobilized ionic liquids with longer alkyl chain length and more nucleophilic anion showed higher activity. In particular, compared with pristine IMIS, zinc halide-combined IMIS (IMIS-Zn) with Cl− exhibited an increased activity, while the IMIS-Zn with Br− and I− showed lower activity than IMIS itself. In addition, the textures of silica supports (surface area and average pore size) have a great impact on the catalytic activity owing to the substance-confined diffusion effects. The recycling experiments showed that the resulting heterogeneous catalysts exhibited good reusability.

Electrical power generation by mechanically modulating electrical double layers

Abstract: Since Michael Faraday and Joseph Henry made their great discovery of electromagnetic induction, there have been continuous developments in electrical power generation. Most people today get electricity from thermal, hydroelectric, or nuclear power generation systems, which use this electromagnetic induction phenomenon. Here we propose a new method for electrical power generation, without using electromagnetic induction, by mechanically modulating the electrical double layers at the interfacial areas of a water bridge between two conducting plates. We find that when the height of the water bridge is mechanically modulated, the electrical double layer capacitors formed on the two interfacial areas are continuously charged and discharged at different phases from each other, thus generating an AC electric current across the plates. We use a resistor-capacitor circuit model to explain the results of this experiment. This observation could be useful for constructing a micro-fluidic power generation system in the near future.