A5056151505- Magnetic confinement fusion research
- Fusion materials and technologies
- Nuclear Physics and Applications
- Nuclear reactor physics and engineering
- Laser-Plasma Interactions and Diagnostics
- Superconducting Materials and Applications
- Stock Market Forecasting Methods
- Particle accelerators and beam dynamics
- Nuclear Materials and Properties
- Atomic and Subatomic Physics Research
- Radiation Detection and Scintillator Technologies
- Ionosphere and magnetosphere dynamics
- Atomic and Molecular Physics
- Plasma Diagnostics and Applications
- Metallurgical Processes and Thermodynamics
- Laser-induced spectroscopy and plasma
- Web Data Mining and Analysis
- Financial Risk and Volatility Modeling
- Recommender Systems and Techniques
- Calibration and Measurement Techniques
- Time Series Analysis and Forecasting
- Infrared Target Detection Methodologies
- Advanced Text Analysis Techniques
- Luminescence Properties of Advanced Materials
- Adaptive optics and wavefront sensing
Korea Institute of Fusion Energy
2014-2024
Ulsan National Institute of Science and Technology
2023
Korea Advanced Institute of Science and Technology
2012-2018
Sungkyunkwan University
2011
Memorial Hospital of South Bend
1990
Chang Gung Memorial Hospital
1990
Experiments on trace argon impurity transport in L-mode discharges were performed Korea superconducting tokamak advanced research (KSTAR) with electron cyclotron resonance heating (ECH). Ar emission was measured by soft x-ray (SXR) arrays and vacuum UV (VUV) diagnostics. A significant reduction the core emissivity observed ECH. The largest on-axis became smaller outward positions. diffusivity convection velocity of obtained analysis SXR data SANCO code for ECH non-ECH shots. In case, both...
This paper examines the use of Large Language Models (LLMs), specifically BERT-based models and GPT-3.5, in sentiment analysis Korean financial analyst reports. Due to specialized language these reports, traditional natural processing techniques often prove insufficient, making LLMs a better alternative. These are capable understanding complexity subtlety language, allowing for more nuanced interpretation data. We focus our study on extraction scores from using them construct test investment...
To optimize the design of ITER vacuum ultraviolet (VUV) spectrometer, a prototype VUV spectrometer was developed. The sensitivity calibration curve calculated from mirror reflectivity, grating efficiency, and detector efficiency. consistent with points derived in experiment using calibrated hollow cathode lamp. For application installed at KSTAR, various impurity emission lines could be measured. By analyzing about 100 shots, strong positive correlation between O VI C IV intensities found.
One of the main missions KSTAR is to develop long-pulse operation capability relevant production fusion energy. After a full metal wall configuration was decided for ITER, major upgrade planned, tungsten first similar JET ITER-like (coatings and bulk plasma-facing components). To accomplish upgrade, bonding technology has been developed tested. Since leading edges each castellation structure have be protected, shaping blocks studied by ANSYS simulation, miniaturized exposed Ohmic plasma...
Experiments with a small amount of Ar gas injection as trace impurity were conducted in the Korea Superconducting Tokamak Advanced Research (KSTAR) H-mode plasma ( = 2.8 T, 0.6 MA, and 4.0 MW). 170 GHz electron cyclotron resonance heating (ECH) at 600 800 kW was focused along mid-plane fixed major radial position 1.66 m. The emissivity Ar16+ (3.949 ) Ar15+ (353.860 spectral lines measured by x-ray imaging crystal spectroscopy (XICS) vacuum UV (VUV) spectrometer, respectively. ECH reduces...
It has been reported that supersonic molecular beam injection (SMBI) is an effective means of edge localized mode (ELM) mitigation. This paper newly reports the changes in ELM, plasma profiles, and fluctuation characteristics during ELM mitigation by SMBI Korea Superconducting Tokamak Advanced Research. During mitigated phase, frequency increased a factor 2–3 size, which was estimated from Dα amplitude, fractional plasma-stored energy line-averaged electron density, divertor heat flux burst,...
This paper addresses the challenges of risk management in financial market through a data-driven approach. In investment management, it is important to detect and avoid anomalies, defined as significant deviations from typical stock price movement patterns. We propose method that utilizes Generative Adversarial Networks (GANs) anomalous patterns prices. devise simple strategies based on GANs-based anomaly detection model validate them real-world data demonstrate if proposed approach can...
A compact advanced extreme-ultraviolet (EUV) spectrometer operating in the EUV wavelength range of a few nanometers to measure spatially resolved line emissions from tungsten (W) was developed for studying W transport fusion plasmas. This system consists two perpendicularly crossed slits—an entrance aperture and space-resolved slit—inside chamber as pinhole, which enables obtain spatial distribution emissions. Moreover, so-called v-shaped slit devised manage size measuring resolution caused...
A solid particle injection system is developed for KSTAR. The has a compact size, compatibility with strong magnetic field and high vacuum environment, the capability to inject small amount of particles narrow angle. target flight-distance 10 cm been achieved loss rate less than 10%. Solid impurity such as tungsten carbon will be injected by this at midplane in transport feature studied soft X-ray array, ultra-violet diagnostic, Stand Alone Non-Corona code.
The ITER vacuum ultra-violet (VUV) core survey spectrometer has been designed as a 5-channel spectral system so that the high resolving power of 200-500 could be achieved in wavelength range 2.4-160 nm. To verify design VUV spectrometer, two-channel prototype was developed. As subsequent step test, operated at KSTAR since 2012 experimental campaign. From impurity injection experiments years 2015 and 2016, strong emission lines, such Kr xxv 15.8 nm, xxvi 17.9 Ne vii 46.5 vi 40.2 an array...
Four-array system of soft X-ray diagnostics was installed on KSTAR tokamak. Each array has 32 viewing chords two photo-diode detectors with spatial resolution 2 cm. To estimate signals from the radiation power, typical ne, Te, and argon impurity line profiles in are chosen. The photo-diodes were absolutely calibrated as a function incident photon energy 2–40 keV range portable tube. Two-dimensional Te image properties by multi-energy method simulated visualized six combinations beryllium...
In the KSTAR Tokamak, a “Tangential Thomson Scattering” (TTS) diagnostic system has been designed and installed to measure electron density temperature profiles. edge system, TTS 12 optical fiber bundles profiles with 10–15 mm spatial resolution. These fibers their resolution are not enough pedestal width high accuracy but allow observations of L-H transition or H-L transitions at edge. For these measurements, prototype ITER Nd:YAG laser manufactured by JAEA in Japan is installed. this...
The first mirror is the front-end optic component that reflects light emitted from plasma to diagnostic system in fusion plasmas. Silicon carbide (SiC), known for its relatively high mechanical strength and radiation tolerance, has been selected as substrate material ITER divertor vacuum ultraviolet (VUV) spectrometer. To measure reflectivity of ellipse cylindrical SiC be manufactured, a device measurement VUV wavelength range was developed. First, sample (15 mm diameter × 10 thick) measured...
Soft X-ray diagnostics at present are not adequate for a burning plasma experiment, neither in term of hardware nor as diagnostic conception. Detectors have to be radiation tolerant, easily shielded, with low sensitivity neutrons and gammas energy discrimination. Layout viewing capability should more flexible, thanks the use also optical devices, going toward configuration intermediate between discrete tomography pure imaging. The general conception these therefore evolve direction pattern...