A5101889060- Supercapacitor Materials and Fabrication
- Electrical Fault Detection and Protection
- Vacuum and Plasma Arcs
- Conducting polymers and applications
- Carbon Nanotubes in Composites
- Advanced Wireless Communication Techniques
- Islanding Detection in Power Systems
- Electrical and Bioimpedance Tomography
- Microgrid Control and Optimization
- Photovoltaic System Optimization Techniques
- PAPR reduction in OFDM
- Electrical Contact Performance and Analysis
- Graphene research and applications
- Advanced Sensor and Energy Harvesting Materials
- Risk and Safety Analysis
- Advanced DC-DC Converters
- Power Systems and Renewable Energy
- Geophysical and Geoelectrical Methods
- Internet of Things and Social Network Interactions
- Solar Radiation and Photovoltaics
- Power Systems Fault Detection
- Electric Motor Design and Analysis
- Fiber-reinforced polymer composites
- Magnetic Bearings and Levitation Dynamics
- HVDC Systems and Fault Protection
Korea Electric Power Corporation (South Korea)
2021-2025
Korea Advanced Institute of Science and Technology
2008-2024
Gachon University
2021
Research Institute of Industrial Science and Technology
2013-2020
Kongju National University
2016-2019
Kwangwoon University
2014
Korea University
2013
Ōtani University
2007
Shinshu University
2002-2006
Japan Science and Technology Agency
2006
The solvated ion size of electrolytes increases in the following order; SO42-(H2O)12 (0.53 nm) < (C2H5)4N+·7acetonitrile (Et4N+·7ACN, 1.30 (C2H5)4N+·4propylene carbonate (Et4N+·4PC, 1.35 nm). difference between nanowindows single-wall carbon nanohorns and ions should be an important factor accessibility to internal spaces through nanowindow.
Novel ionic liquids comprised of a quaternary ammonium salt type cation have been applied to an electrolyte for high-performance electric double-layer capacitors (EDLCs). The novel [IL-B; , -diethyl--methyl(2-methoxyethyl)ammonium tetrafluoroborate and IL-T; bis(trifluoromethylsulfonyl)imide (DEME-TFSI)] are promising candidates EDLC electrolytes in terms high decomposition voltage (wide window), nonflammability, easy handling, nonvolatility, low production costs. Notably, the wide window...
As an essential part in technologies for energy storage systems (ESSs) or renewable (RESs), grid‐connected inverters need power passive filters to meet grid regulations. typical filters, L filter and LCL are employed. Although is more cost‐effective than filter, a design of complicated filter. has three elements: inverter‐side inductor, grid‐side capacitor. To the elements simultaneous equations should be required, which means that target exist. Since conventional methods do not suggest...
We investigated the importance of specific effective surface area through a detailed study on relationship between electrical conductivity single-walled carbon nanohorns (SWCNHs) and accessibility electrolyte ions in SWCNH-based supercapacitor. After heat treatment SWCNHs, ratio sp2/sp3 carbons dramatically increased, suggesting an enhanced SWCNHs. Even though (SSA) slightly decreased by 16% as result treatment, capacitance per SSA SWCNH electrode remarkably increased from 22 to 47 μF cm–2....
Worldwide, efforts are underway to produce hydrogen from water electrolysis, moving beyond the traditional reforming of fossil fuels. Renewable energy-powered production is possible, but use grid power also being considered for large-scale production. Additionally, some demonstration projects aim utilize electrolysis systems as auxiliary service resources enhance stability in grid, given rising share renewable energy. This study proposes a method connecting facilities based on voltage...
Recently, Low-Voltage DC (direct current) distribution systems have received high lights according to the expansion of generations and loads such as photovoltaics (PV) generations, electric vehicles (EVs), light emitting diodes (LEDs), computers, homes, etc. optimistic perspectives since has various good aspects compared alternating current (AC). However, ensuring safety human facility in is not easy because arc generation difficulty arc-extinguishing. This paper constructs a low-voltage...
Multimode large core (45×35 μm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> ) optical ridge waveguides are fabricated in the room temperature by ultraviolet (UV) imprinting of soft rubber template with organic-inorganic sol-gel hybrid materials. The fabrication processes may be either well-known UV embossing or stamping. A new material that is thermally stable has been developed for low-loss waveguides. curable methacrylic used layer...
A slotless permanent magnet linear synchronous motor (PMLSM) has a low power density due to having large air-gap structurally. In this paper, an increase of the slotless-type PMLSM is presented by inserting core between each phase windings. The (PM) divided into two pieces reduce detent force and eliminate high-order space harmonics affecting thrust ripples. All analysis values are calculated with two-dimensional finite-element method.
Successful commercialization of holographic printers based on stereograms requires a tool for their numerical replaying and quality assessment before the time-consuming expensive process recording. A stereogram encodes 2D images 3D scene that are incoherently captured from multiple perspectives rearranged This study presents simulator which builds full parallax color white light viewable perspective by virtual recentering camera with its further reconstruction any viewer location. By...
In electric distribution systems, a series arc occurs when load and power source are disconnected from connector such as circuit breaker, socket-plug, or coupler. dc the is not extinguished unless current decreases to zero. Sustaining plasma can cause huge fire disasters. To cope with faults in characteristics of should be analyzed. However, clear analysis method has been suggested. This paper analyzes series-breaking breaker three operation phases: initiation, sustenance, extinguishment....
The fundamental question regarding the fractionation phenomenon is whether diffusion alone responsible for it or an additional advection dynamic involved. We studied by of particles in spatially heterogeneous environments. By experimentally observing time-sequential patterns dye diffusing across a solid-solid interface varying polyacrylamide gel densities, we found that two-component model accurately captures observed dynamics. In contrast, single-component models Fick, Wereide, and Chapman...
Interfacial importance and nanopore structures of single wall nanocarbons such as carbon nanotube (SWCNT) nanohorn (SWCNH) are described in terms intermolecular interaction theory. The relationships between the structure nanoconfinement effect for molecules ions shown using examples on supercritical H2 adsorption SWCNT, quantum molecular sieving SWCNT D2 below 77 K, water hydration Rb, Cs, Sr nanopores activated fiber SWCNH, capacitance storage SWCNH. produced by laser ablation shows...
Solar power generation systems require maximum point tracking (MPPT) control to get using low efficient and high cost PV modules. Most of the conventional MPPT algorithms are based on slope-tracking concept. One a typical method is Perturb Observe (P&O) algorithm. The two factors that determine performance P&O algorithm period magnitude perturbation voltage. When voltage set large, controller quickly moves new at insolation change, while error output will be huge in steady state even when...
The orthogonal frequency division multiplexing (OFDM) technique has been adopted for the European digital terrestrial broadcasting standard, which is called video (DVB-T). In this paper, we propose a new symbol timing recovery algorithm system to achieve fast start-up using scattered pilots under offset, common phase error, and severe noise. With proposed algorithm, can detect up /spl plusmn/35 sample offsets recover sampling even in carrier offset of plusmn/0.35 OFDM subcarrier space. So,...
Grid injecting ac current from grid connected inverters contains harmonic components which can be effectively attenuated by LCL type filters with comparably low filter cost. Recent researches tell that the harmonics stem not only high order PWM switching itself but also dead time control for switching. However, are fully investigated yet. This paper shows ratio of inductances in is one important factors relating performance. analyses frequency responses to get optimal inductance inverters....
In electric distribution systems, a parallel arc is caused by short circuit resulting from insulation breakdown of wire or aged equipment. A series occurs when load and power source are disconnected connector such as breaker, socket-plug coupler. DC these arcs not extinguished unless the current decreases to zero. Sustaining plasma can cause huge fire disasters. To cope with faults in characteristics should be analyzed. Methods extinguish researched. The follows Paschen's law found 1889. It...
Thermal diffusion has been studied for over 150 years. Despite of the long history and increasing importance phenomenon, physics thermal remains poorly understood. In this paper Ludwig's is explained using Einstein's random walk. The only new structure added spatial heterogeneity walk to reflect temperature gradient diffusion. Hence, length speed are location dependent functions in paper. Then, a mathematical understanding such gives foundation as clearly original homogeneous case Einstein.