A5058092954- Physics of Superconductivity and Magnetism
- Superconducting Materials and Applications
- Thin-Film Transistor Technologies
- Electric Motor Design and Analysis
- ZnO doping and properties
- Frequency Control in Power Systems
- Neuroscience and Neural Engineering
- Silicon and Solar Cell Technologies
- Magnetic Properties and Applications
- Spacecraft and Cryogenic Technologies
- Engineering Applied Research
- GaN-based semiconductor devices and materials
- Gas Sensing Nanomaterials and Sensors
- Advanced Memory and Neural Computing
- Induction Heating and Inverter Technology
- Magnetic Field Sensors Techniques
- Quantum Information and Cryptography
- Neural Networks and Reservoir Computing
- Electrostatic Discharge in Electronics
- Particle accelerators and beam dynamics
- HVDC Systems and Fault Protection
- Phase-change materials and chalcogenides
- Silicon Carbide Semiconductor Technologies
- Silicon Nanostructures and Photoluminescence
- Advanced Optical Sensing Technologies
Seoul National University
2019-2025
The Ohio State University
2006
Abstract Brain‐inspired neuromorphic computing has drawn significant attraction as a promising technology beyond von Neumann architecture by using the parallel structure of synapses and neurons. Various artificial synapse configurations materials have been proposed to emulate synaptic behaviors for human brain functions such memorizing, learning, visual processing. Especially, memory type indium‐gallium‐zinc‐oxide (IGZO) transistor adopting charge trapping layer (CTL) advantages high...
Quantum dots (QDs) have garnered a significant amount of attention as promising memristive materials owing to their size-dependent tunable bandgap, structural stability, and high level applicability for neuromorphic computing. Despite these advantageous properties, the development QD-based memristors has been hindered by challenges in understanding adjusting resistive switching (RS) behavior QDs. Herein, we propose three types InP/ZnSe/ZnS elucidate RS mechanism, employing thin poly(methyl...
This paper presents a design study on 40 MW synchronous motor having no-insulation (NI) high-temperature superconductor (HTS) field coils. An in-house analytic code was used to obtain first-cut based the published parameters of AMSC 36.5 ship propulsion as reference. Then, refinement followed using finite-element method more accurately simulate electromechanical behaviors motor. After final completed, transient torque responses NI motor, in no load and full conditions, were simulated with...
This paper presents a “combined” circuit model to simulate non-linear behaviors of no-insulation (NI) high temperature superconductor (HTS) coil. The key idea is selective use either the lumped or distributed depending on an operating condition. When NI coil current below its critical current, radial leak currents through turn-to-turn contacts may be assumed uniformly over entire coil, thus, suffice analyze behaviors. increases beyond plays role spatial distribution currents, both and...
In this work, the self-aligned coplanar top gate In-Ga-Zn-O thin-film transistor with a stepped substrate structure was investigated to suppress short-channel effect. Usually, <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\text{V}_{\text {th}}$ </tex-math></inline-formula> roll-off occurs as channel length decreases due large and source/drain overlap ( notation="LaTeX">$\Delta \text{L}$ ), attributed...
As global environment regulations are gradually strengthened, active research has been conducted on electric propulsion applications. High power density is one of the major interests, as well a machine's efficiency for high-performance system. Among various technologies under development, motor incorporating no-insulation (NI) high-temperature superconducting (HTS) winding advantages high current and robustness to external disturbances, which suitable specific power. However, still, there...
When a quench occurs in no-insulation (NI) high temperature superconductor (HTS) magnet that consists of stack double-pancake (DP) coils, large amount current is often induced an NI DP coil electromagnetically coupled with neighboring coils. The leads to excessive magnetic stress and occasionally damages the magnet. In this paper, we propose new protection concept reduce HTS key idea use resistive copper order absorb portion electromagnetic energy initially stored before quench. We...
This paper proposes an approach to account for a fast electromagnetic quench propagation among electromagnetically coupled no-insulation (NI) high temperature superconductor (HTS) coils. Recently, multiple groups have reported that the conventional lumped-circuit model, which has well demonstrated charging and discharging behaviors of NI magnet, could not post-quench behaviors. Specifically, terminal voltages individual pancake coils were estimated be too than simulated ones. focuses on...
This paper presents numerical studies on the mechanical behavior of dry-wound high-temperature superconducting (HTS) racetrack coil. After calculating Lorentz force induced from self-field coil based 3D finite element method (FEM), 2D stress analysis is performed plane-stress assumptions to mitigate computational loads, and including displacement are investigated. Based model, two following case conducted: 1) various-shaped coils having a different ratio straight section length semicircular...
Recently an induction heating system comprising a pair of no-insulation high-temperature superconductor (HTS) racetrack coils was built and now it is commercially available. It generates direct current (dc) magnetic field in which conductive metallic billet rotates at high speed. Most dc machines accommodate "single" per operation. This paper proposes alternative concept "multiple-billet" heater, where the multiple billets can be <italic xmlns:mml="http://www.w3.org/1998/Math/MathML"...
This paper proposes a new equivalent circuit model to calculate current distribution in an NI (no-insulation) high temperature superconductor (HTS) coil that contains defect. When the well-known defect irrelevant behaviors of HTS are analyzed, so-called partial element (PEEC) technique has been commonly adopted. However, PEEC often takes extremely long time, days or even weeks, for just single simulation depending on number internal elements within target coil. Here we propose alternative...
This paper presents a numerical method, named "Segmentation" to calculate spatial harmonic coefficients of magnetic fields generated by both transport and screening currents in high temperature superconductor (HTS) magnet. Once current distributions the individual turn an HTS magnet are obtained using finite element analysis (FEA) based on edge-element H-formulation domain homogenization technique, flowing is divided into multiple "segments" equivalent loop each segment calculated...
Superconducting quantum bits (qubits) are considered as promising candidates to serve a platform for information processor. For the realization of practical computing devices, scalable designs and long lifetimes qubits required. In this paper, we present simulation results “hexagonal” transmon qubit in superconducting coplanar waveguide (CPW) resonator. We conducted finite-element method simulations considering dielectric losses including two-level system (TLS) loss evaluate performance...
In this paper, high subthreshold swing (SS) amorphous In‐Ga‐Zn‐O (a‐IGZO) thin‐film transistors (TFTs) were fabricated using a sputtered Al2O3 layer, which was deposited on an active layer of the conventional bottom‐gate a‐IGZO TFTs and patterned photolithography. By optimizing Al 2 O 3 SS without mobility degradation could be achieved.
This paper presents comparative research on characteristics of air-cored and iron-cored high-temperature superconductor (HTS) field winding synchronous motors. The 100 kW model is designed analytically by Spatial Harmonic Method, based this model, the having same output power for comparison. Due to substantial difference permeability property between air iron-core, there a magnetic magnitude angle with respect HTS tape c-axis, resulting in different critical current considering anisotropic...
Views Icon Article contents Figures & tables Video Audio Supplementary Data Peer Review Share Twitter Facebook Reddit LinkedIn Tools Reprints and Permissions Cite Search Site Citation Y. Shiroyanagi, G. Gopalakrishnan, S. An, T. J. Gramila; Implementation of a Baffle Cooled Approach for Cryostat Magnet Lead System. AIP Conf. Proc. 7 September 2006; 850 (1): 1653–1654. https://doi.org/10.1063/1.2355342 Download citation file: Ris (Zotero) Reference Manager EasyBib Bookends Mendeley Papers...
In general, when evaluating a performance of high-temperature superconductor (HTS) no-insulation (NI) magnet, current, voltage, and center magnetic field are considered as main parameters. To achieve detailed results the parameters NI HTS distributed circuits which can analyze internal physical phenomena magnet required. Among circuits, circuit that divides inside each turn into several cells in azimuthal direction is called Partial Element Equivalent Circuit (PEEC). this paper, we compared...