• Journal of The Korean Astronomical Society
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• v.29 no.spc1
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• pp.291-294
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• 1996

The .Japanese sun observing satellite, Yohkoh, has been operational for five years and her scientific instruments are still in good condition. They have revealed ample of evidences that solar flares were triggered by magnetic reconnection, which was, for the first time, clearly indicated to take place in the solar corona. Cusp structures in soft X-rays and a new type of hard X-ray sources at the top of flaring loops have strongly supported the scenario originally proposed by C-S-H-KP. Nonthermal energy input in hard X-rays and thermal energy estimated from soft X-rays are fundamentally consistent with the interpretation of thick-target and chromospheric-evaporation models (Neupert effect). X-ray jets, another discovery of Yohkoh, were also associated with magnetic reconnection, as a result of the interaction of emerging fluxes with pre-existing coronal loops. Temperature structures of active regions, quiet sun, and coronal holes had very dynamic differential-emission-measure (DEM) distributions and high-temperature tails of DEM were considered to come from the contribution of flare-like activity.

• 전기의세계
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• v.28 no.10
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• pp.48-54
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• 1979

The electrification phenomena of polymerized materials is governed by the competitive processes of the charge generation and the charge dissipation. In this paper, The charged particles were supplied on the naked upper surface of the polyethylene film from a point corona discharge with a screen electrode which controls the potential difference across the film. The charging current with the corona charging was found to be larger than that obtained with the electric charging on the MIM structure and the discharge current was found to flow in the same direction as that of the charging current. these results can suggest that the charge injection occurs from the interface between the polethylene surface and the accumulated charge layer, the injected charge are trapped and the space charge is established.

• Proceedings of the KIEE Conference
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• 1999.07e
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• pp.2010-2012
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• 1999

The product of electrons by Pulsed Corona Discharge leads to produce radicals which work on NO, and NO is finally removed. Energy efficiency for NO removal was improved with increasing peak voltage rather than with increasing pulse frequency. The rate of energy transfer increased with decreasing value of $C_p$( Pulse - Forming Capacitance 2.15, 1.06, 0.55, 0.36, 0.1[nF]. When the value of $C_p$ reached to 0.36 [nF], the energy efficiency for NO removal was maximized. And good agreement was obtained between chemical kinetic calculations and the experimental results.

• Environmental Engineering Research
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• v.11 no.3
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• pp.164-171
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• 2006

Numerical modeling of the flow velocity fields for the near corona wire electrohydrodynamic (EHD) flow was conducted. The steady, two-dimensional momentum equations have been computed for a wire-plate type electrostatic precipitator (ESP). The equations were solved in the conservative finite-difference form on a fine uniform rectilinear grid of sufficient resolution to accurately capture the momentum boundary layers. The numerical procedure for the differential equations was used by SIMPLEST algorithm. The Phoenics (Version 3.5.1) CFD code, coupled with Poisson's electric field, ion transport equations and the momentum equation with electric body force were used for the numerical simulation and the Chen-Kim ${\kappa}-{\varepsilon}$ turbulent model numerical results that an EHD secondary flow was clearly visible in the downstream regions of the corona wire despite the low Reynolds number for the electrode ($Re_{cw}=12.4$). Secondary flow vortices caused by the EHD increases with increasing discharge current or EHD number, hence pressure drop of ESP increases.

• The Journal of Korean Physical Therapy
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• v.22 no.6
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• pp.53-58
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• 2010

Purpose: Our goal was to determine the difference in motor recovery between two stroke types: the corona radiata (CR) infarct type and the intracerebral hemorrhage (ICH) type, by using assessment methods for motor functions. Methods: Forty subjects who were diagnosed as having had a stroke with an infarct (men: 11, women: 9, mean age: $62.25{\pm}7.59$) or a stroke with an ICH (men: 12, women: 8, mean age: $59.75{\pm}6.11$) were recruited. In all subjects, motor functions of the affected extremities were measured 2 times: at stroke onset (initial) and 6 months after the onset (final) by the motricity index (MI), the modified Brunnstrom classification (MBC), and functional ambulatory category (FAC). We compared the final assessment with the initial one. Results: Motor functions of all patients improved with the passing of time. All scores of motor function assessment in the ICH type were higher than in the infarct type. Comparing the initial assessment with the final one, upper MI and MBC scores of the upper extremities were significantly different between the two stroke types (p<0.05), but lower MI and FAC scores of the lower extremities were not (p>0.05). Conclusion: These findings imply that patterns of motor recovery in patients with either the infarct type or the ICH type of stroke change for the better over time. The degree of motor recovery in the ICH type was better than in the infarct type. Therefore, one can introduce clinical interventions by the aspect of progress in functional motor recovery.

• The Journal of Internal Korean Medicine
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• v.42 no.5
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• pp.1131-1141
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• 2021

Objective: This study examined the case of a 63-year-old man with a history of hypertension and gout who had developed an intracerebral hemorrhage (ICH) of the right basal ganglia of the corona radiata. Methods: The patient was treated with herbal medicine (Boyanghwanoh-tang and powdered Oryeong-san extract), Western medicine (Anticonvulsants, antihypertensive drugs, psychotropic agents, and others), acupuncture, moxibustion, cupping, and rehabilitative therapy. Their effects were evaluated using the Manual Muscle Test (MMT), Korean version of the modified Barthel Index (K-MBI), National Institute of Health's Stroke Scale (NIHSS), and Modified Rankin Scale (mRS). Results: After treatment, the MMT grade improved from 3/3+ to 4+/4+. Additionally, the K-MBI score improved from 62 to 77. Conclusion: The results suggest that combined traditional Korean and Western medicine can effectively treat patients with ICH.

• Proceedings of the KIEE Conference
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• 2004.07c
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• pp.1781-1783
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• 2004

Flue gas from fossil fuel combustion is the main source of air pollution. It is recognized that $SO_2$ and $NO_x$, (sum of NO and $NO_2$) react with $H_2O$ and $O_2$ in atmosphere and convert precursors of acid rain. Streamer corona process using pulse power is one of the effective methods to remove these gases from stack. For this, pulse generator with 160 kV of output peak voltage, 0.3 ${\mu}s$ of pulse width and 120Hz of pulse repetition rate is developed. This paper shows the pulse compression characteristics to obtain optimum parameters for basic system design.

• Journal of the Korean Society of Combustion
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• v.8 no.1
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• pp.9-16
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• 2003

Carbon soot emission from combustion processes, especially from diesel engines, is a subject of growing concern since soot is known to seriously affect human health. Efforts have been made to oxidize soot particles utilizing Non-Thermal Plasma(NTP) techniques. When oxygen is carried into a plasma device, electrons generated by the plasma dissociate the oxygen, resulting in the formation of oxygen atoms. These highly activated atoms, called O radicals, are known as strong oxidizing agent. This paper presents concentration variations of CO and $CO_2$ at the exit of the plasma device, resulting from the soot oxidation by O radicals, with variations of inlet oxygen concentration, gas temperature, and gas flow rate. Based on the data, Arrehenious rate constants of reactions between C(s)+O and C(s)+O+O were proposed.

• Journal of Electrical Engineering and Technology
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• v.10 no.5
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• pp.2077-2082
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• 2015

Based on Deutsch assumption, a calculation method on the electric field over the ground surface under HVDC transmission lines in the wind is proposed. Analyzing the wind effects on the electric field and the space charge density the existing method based on Deutsch assumption is improved through adding the wind speed to the ion flow field equations. The programming details are illustrated. The calculation results at zero wind speed are compared with available data to validate the code program. Then the ionized fields which resulted from corona of ±800kV HVDC lines are analyzed. Both the electric field and the current density on the ground level are computed under different wind direction and speed. The computation results are in good agreement with measurements. The presented method and code program can be used to rapidly predict and evaluate the wind effects in HVDC transmission engineering.

• 전자공학회논문지 IE
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• v.46 no.3
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• pp.26-32
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• 2009

The reason of the contamination in the VLSI industry is the electric charge of the wafer itself. We develop the corona discharged system of clearing static electricity with a fan. This system has automatic cleaner of discharging electrode, check the state of jot control a suitable mount of discharged ion, and monitor all state using Zigbee communication module.