• Proceedings of the KIEE Conference
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• 2009.07a
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• pp.840_841
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• 2009

본 논문은 2차원 유한요소법을 이용하여 2[MVA]급 몰드변압기의 과도전계를 해석한 것이다. 과도현상을 해석하기 위해 변압기 코일 및 대지 간 정전용량을 에너지법을 이용하여 구하였고, 이를 이용하여 변압기에 충격전압 95[kV]가 인가될 경우에 변압기 위치별 전계의 세기를 구하였다.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2010.07a
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• pp.237-240
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• 2010

현재까지 실감 기술이 3-D 오디오나 비디오를 통하여 발전되어 왔지만, 단순히 시청각만을 통해서는 사용자에게 진정한 실감을 느끼도록 하기 힘들다. 사람은 오감을 통하여 모든 사물을 인지하므로 진정한 실감을 얻으려면 미디어를 통하여 인간의 다양한 감각을 모두 느낄 수 있도록 해 주어야 한다. 본 논문은 사용자 주변의 다양한 실감 디바이스들을 오디오, 비디오 콘텐츠와 동기를 맞추어 제어하므로 실감을 높일 수 있는 미디어 서비스 개념인 SMMD(Single Media Multiple Device) 미디어 시스템과 SMMD 미디어를 생성하기 위한 저작툴에 관하여 설명한다.

• Journal of Astronomy and Space Sciences
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• v.15 no.1
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• pp.27-38
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• 1998

We discussed four different methods - the single, double and triple Gaussian fits, and the intensity weighted centroid fit - which extract rotation curves from several emis-sion lines(i.e. [OII], $H{\beta}$, [OIII], and $H{\alpha}$) of spiral galaxies. Spatial extents and the shapes of rotation curves derived through various methods applying to each emission lines of a sample galaxy UGC 11635 are all in a good agreement with one another. Linewidths of $H{\beta}$ and $H{\alpha}$ measure from rotation profiles are in a good agreement with $H{\alpha}$ linewidth of Courteau (1992). however, linewidths of [OII] seems to be much broader than $H{\alpha}$, and the profile of [OIII] does not follow the profile of $H{\alpha}$.

• Journal of Astronomy and Space Sciences
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• v.15 no.1
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• pp.39-48
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• 1998

We present the results of a search for photometric variable blue straggler stars(BSSs) in the globular cluster M53. Six of 151 probable BSSs are identified as variable candidates based on the robust variable star detection technique of Welch & Stetson (1993). Most variable BSS candidates appear to occupy the instability strip in the color-magnitude deagram, and they appear to have visual light amplitudes of 0.2 mag-0.3 mag. Further observations are required, however, to resolve the natrue of variabil-ity between pulsating stars and eclipsing binaries for these variable BSS candidates.

• Journal of Astronomy and Space Sciences
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• v.15 no.1
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• pp.1-26
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• 1998

The structure of the magnetic funnel element in the intermediate polar is con-sidered in terms of an important site for the X-ray absorption and the reemis-sion of the X-ray as the optical light. In this paper the column density and the optiacl depth vary with the filling factor, which is introduced to characterize the structure of matter in the magnetic funnel element. The results of the en-ergy dopendence of the X-ray spectrum and the modulation depth of the X-ray light curve are discussed.

• Journal of Astronomy and Space Sciences
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• v.16 no.2
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• pp.115-130
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• 1999

We report the discovery of 17 new RR Lyrae variables in the central region ($\rleq1'$) of the globular cluster M53. There candidates were identified by using the Welch & Stetson (1993) technique and confirmed by checking individual light curves in both B and V bands. The color-magnitude diagram of the horizontal-branch stars in the central region is compared with that for stars observed in the outer region by Rey et al. (1998). Including the new data from this study, we estimate the fraction of c typeRR Lyrae variables, n(c)/n(ab + c), to be 0.43 which agrees well with the valuse of other Oosterhoff group II clusters.

• Bulletin of the Korean Space Science Society
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• 1993.04a
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• pp.14.2-14
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• 1993

We present UBV CCD Photometry of the very metal-poor globular duster M3O,covering a region of r f 100 arcsec from the duster center. The data was obtained from the 40 inch telescope at Mt Soomlo Siding Spring Observator in August 1992. We used DAOPHOT CCD reudction package for data reduction to obtain Color-Magnitude Diagram(CMD). We have determined some fludamental parameters of the globular Ouster such as metal abundance, helium abundance and distance from the CMD. finally, we have attempted to determine the age of M3O using the revised Yale isochrones.

• Journal of Astronomy and Space Sciences
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• v.12 no.1
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• pp.1-13
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• 1995

We carried out photometric and spectroscopic observatious of the blue compact dwarf galaxy Haro 6 in the Virgo Cluster of Galaxies. The long-slit spectroscopy was employed at three position angles, $\Phi$=$0^{\circ}$, $\Phi$=$30^{\circ}$, and $\Phi$=$120^{\circ}$with CCD camera mounted on the Cassegrain Spectrograph. Based on the mean intrinsic axial ratio < $q_0$ >=0.3, we derived inclination I of the system as $44^{\circ}$using our composite V-band CCD image. Careful analysis on the velocity field of the system shows an asymptotically fiat rotation curve with the maximum rotational velocity $V(r)_{max}$ reaches about 12km/sec. The calculation of the dynamical mass of Haro 6 with a simple mass model is briefly discussed with emphasis on the mass to luminosity ratio. From the IRAS Point Source Cataloque, we derived dust-to-gas ratio which indicates relatively low dust content, thus tempting us to conjecture the youth of the system.

• Journal of Applied Reliability
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• v.9 no.2
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• pp.121-130
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• 2009

The power law process model the Rate of occurrence of failures(ROCOF) with monotonic trend during the operating time. However, the power law process is inappropriate when a non-monotonic trend in the failure data is observed. In this paper we deals with the reliability modeling of the failure process of large and complex repairable system whose rate of occurrence of failures shows the non-monotonic trend. We suggest a sectional model and a change-point test based on the Schwarz information criterion(SIC) to describe the non-monotonic trend. Maximum likelihood is also suggested to estimate parameters of sectional model. The suggested methods are applied to field data from an repairable system.

• 한국정보디스플레이학회:학술대회논문집
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• 2007.08b
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• pp.1586-1589
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• 2007

The influence of optical components constituting the backlight of TV on the luminance property of backlight was analyzed. The variation of luminance when the light emitted from light source passes each optical part was evaluated.