• Journal of The Korean Astronomical Society
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• v.28 no.1
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• pp.77-87
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• 1995

An attempt has been made to analyze time series of $H_\alpha,\;H_\beta,\;and\; H_\gamma$ line profiles taken from a 3B/X6.1 flare which occurred on Oct. 27, 1991 in an active region, NOAA 6891. A total of 22 sets of $H_\alpha,\;H_\beta,\;and\; H_\gamma$ taken with a low and non-uniform time resolution of 10-40 seconds were scanned by PDS with absolute intensity calibration to derive the physical characteristics of the material in the flare chromosphere. Our . results are as follows: (1) The lower Balmer lines observed during the flare activity are broadened by Stark effect. (2) At the peak of the flare activity, the electron temperature of the Balmer line emitting region reaches up to 35000K and its geometrical thickness increases to a scale of $10^4km$, suggesting that high energy particles penetrate deep into the photospheric level.

• Journal of The Korean Astronomical Society
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• v.29 no.2
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• pp.217-221
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• 1996

We have examined morphological change and movements of individual sunspots within a sunspot group in association with a large solar flare activity (3B/X1.5) appeared on 13 May 1981. For this purpose we measured distance among spots during the period before and after the flare activity and estimated the average velocity of their movement. Our main results are as follows: (1) The longitudinal displacement among sunspots are generally greater than the latitudinal displacement. (2) During the period the spots moved with an average velocity of 1.2 km/s in longitude and 0.86 km/s in latitude. (3) The most notable change took place in the central part placed between the two ribbons of the flare.

• Journal of the Korean Home Economics Association
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• v.36 no.2
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• pp.121-130
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• 1998

The purpose of this study was construction of bell-bottom blue jeans according to change of flare line and investigate the effects clothing pressure according to various movements of the legs. In this study, movements of leg were classified by M1, M2, M3, M4.(M1:erecting, M2: leapfrogging position, M3:sit-on-one' keens position, M4:Traditional nobel-sitting position) The results were as follows: As usings the leg surface shell by the adhesive paper taping method, basic slacks pattern and blue jeans patterns according to change of flare line was constructed. The order of clothing pressure of the different patterns is C(the flare line is on the calf of the leg)>B(the flare line is on the knee)>A(the flare line is on the thigh). Clothing pressure in the knee point was highest and when the flare line was on the calf of the leg, clothing pressure showed high.

• Restorative Dentistry and Endodontics
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• v.30 no.2
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• pp.102-111
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• 2005

The purpose of this study was to assess the incidence of flare-ups among patients who received endodontic treatment and to examine the correlation with pre-operative and operative variables. Analysis was in two aspects (a) overall incidence of flare-ups as expressed by a percentage of all patients visits and (b) percentage of flare-ups that occurred as related to various factors suck as patient demo-graphics, diagnosis, and treatment procedures. 1. From the 840 teeth which were examined in this study, the total number of flare-ups was 13. 2. As to gender of patients, there was no significant difference in flare-ups. 3. As to tooth groups, there was no significant difference in flare-ups. 4. In the teeth with pre-operative symptom, there was a statistically significant higher incidence of flare-ups than the teeth without it. 5. In the teeth with apical periodontitis, there was a statistically significant higher incidence of flare-ups. 6. As to pulp and periapical status. non-vital teeth had a higher incidence as compared with vital teeth, irreversible pulpitis. 7. Multi-visit treatment resulted in the higher incidence of flare-ups than one visit treatment. 8. Re-treatment procedures had a statistically significant higher incidence of flare-ups than root canal treatment. In this study, overall percentages of flare-ups was $1.55\%$. It showed a statistically significant higher incidence related to pre-operative symptom, apical periodontitis, and re-treatment. There was no significant difference in flare-ups related to gender, tooth groups, and fistula.

• Journal of The Korean Astronomical Society
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• v.34 no.2
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• pp.111-117
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• 2001

Recently, we have set up a new digital CCD camera system, MicroMax YHS-1300 manufactured by Roper Scientific for Ha observation by Solar Flare Telescope at Bohyunsan Optical Astronomy Observatory. It has a 12 bit dynamic range, a pixel number of 1300$\times$1030, a thermoelectric cooler, and an electric shutter. Its readout speed is about 3 frames per second and the dark current is about 0.05 e-/p/s at $-10^{\circ}C$. We have made a system performance test by confirming the system linearity, system gain, and system noise that its specification requires. We have also developed a data acquisition software which connects a digital camera con-troller to a PC and acquires H$\alpha$ images via Microsoft Visual C++ 6.0 under Windows 98. Comparisons of high quality H$\alpha$ images of AR 9169 and AR 9283 obtained from SOFT with the corresponding images from Learmonth Solar Observatory in Australia confirm that our H$\alpha$ digital observational system is performed properly. Finally, we present a set of H$\alpha$ images taken from a two ribbon flare occurred in AR 9283.

• The Bulletin of The Korean Astronomical Society
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• v.19
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• pp.8.1-8.1
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• 1994

• Journal of Chest Surgery
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• v.12 no.1
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• pp.16-22
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• 1979

Clinical evaluation of contact sensitization to 2, 4-dinitro-chlorobenzene [DNCB] was performed in 2 groups: group A [30 patients with non-malignant disease] and group B [30 patients with bronchogenic carcinoma]. Initial sensitization was elicited out by applying 2, 000 ug of DNCB to skin surface of the both group A and B. Subsequently a relatively weak challenge dose, 200 ug of DNCB, was applied 14 days later, showing the satisfactory results of sensitization with minimizing non-specific irritative inflammatory skin response. Delayed cutaneous hypersensitivity reactions shown by spontaneous flare phenomena appeared at the challenge site, and they were assessed 48 hours later. The reaction were graded from +1 to +4 according to the degree of flare or vesicular reaction. The results were as follows: 1. 28 cases [93%] of group A, however, only 18 cases [67%] of group B exhibited delayed cutaneous hypersensitivity reaction to DNCB contact sensitization [P<0.02]. 2. Of group A, the delayed cutaneous hypersensitivity reactions above +2 of DNCB score were 25 cases [83%], meanwhile 11 cases [37%] in group B [P<0.001]. 3. Undifferentiated carcinomas showed highest incidence of anergy to DNCB contact sensitization in the all histologic types of group B. 4. In group B, 8 [42%] of 19 cases who react to DNCB were resectable, whereas only 2 [18 %] of 11 cases who failed to react to DNCB were resectable for curative cancer surgery. These study suggests that cellular immune reaction of group B was depressed remarkably comparing with that of group A.

• The Bulletin of The Korean Astronomical Society
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• v.37 no.1
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• pp.85.2-85.2
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• 2012

In this paper, we introduce the 3D modeling of the coronal magnetic field in the solar active region by extrapolating from the 2D observational data numerically. First, we introduce a nonlinear force-free field (NLFFF) extrapolation code based on the MHD-like relaxation method implementing the cleaning a numerical error for Div B proposed by Dedner et al. 2002 and the multi-grid method. We are able to reconstruct the ideal force-free field, which was introduced by Low & Lou (1990), in high accuracy and achieve the faster speed in the high-resolution calculation (512^3 grids). Next we applied our NLFFF extrapolation to the solar active region NOAA 10930. First of all, we compare the 3D NLFFF with the flare ribbons of Ca II images observed by the Solar Optical Telescope (SOT) aboard on the Hinode. As a result, it was found that the location of the two foot-points of the magnetic field lines well correspond to the flare ribbon. The result indicates that the NLFFF well capture the 3D structure of magnetic field in the flaring region. We further report the stability of the magnetic field by estimating the twist value of the field line and finally suggest the flare onset mechanism.

• Journal of the Korea Institute of Military Science and Technology
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• v.18 no.3
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• pp.267-274
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• 2015

It is necessary to both analyze root-cause of non-conformance of effective illumination time to the specification, and estimate the storage lifetime for 81 mm illuminating projectile stockpiled over 10 years. In this paper, aging mechanism of magnesium flare material due to long-term storage was supposed, and two-stage tests, pre-test and main test based on accelerated degradation tests were performed. Field storage environment of moistureproof was set up, and illumination times in the accelerated degradation tests for temperatures 60 and $70^{\circ}C$ were measured. Then, storage reliability of the projectile was estimated through analyzing the measured data and applying distribution-based degradation models to the data. The $B_{10}$ life by which 10 % of a population of the projectiles will have failed at storage temperature of $25^{\circ}C$ was estimated about 7 years.

• Journal of The Korean Astronomical Society
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• v.33 no.1
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• pp.47-55
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• 2000

Nonpotential characteristics of magnetic fields in AR 5747 are examined using Mees Solar Observatory magnetograms taken on Oct. 20, 1989 to Oct. 22, 1989. The active region showed such violent flaring activities during the observational span that strong X-ray flares took place including a 2B/X3 flare. The magnetogram data were obtained by the Haleakala Stokes Polarimeter which provides simultaneous Stokes profiles of the Fe I doublet 6301.5 and 6302.5. A nonlinear least square method was adopted to derive the magnetic field vectors from the observed Stokes profiles and a multi-step ambiguity solution method was employed to resolve the $180^{\circ}$ ambiguity. From the ambiguity-resolved vector magnetograms, we have derived a set of physical quantities characterizing the field configuration, which are magnetic flux, vertical current density, magnetic shear angle, angular shear, magnetic free energy density, a measure of magnetic field discontinuity MAD and linear force-free coefficient. Our results show that (1) magnetic nonpotentiality is concentrated near the inversion line in the flaring sites, (2) all the physical parameters decreased with time, which may imply that the active region was in a relaxation stage of its evolution, (3) 2-D MAD has similar patterns with other nonpotential parameters, demonstrating that it can be utilized as an useful parameter of flare producing active region, and (4) the linear force-free coefficient could be a evolutionary indicator with a merit as a global nonpotential parameter.