• Publications of The Korean Astronomical Society
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• v.30 no.2
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• pp.47-51
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• 2015

Ground Level Enhancements (GLEs) in cosmic ray intensity observed during the period of 1997-2012 have been studied with energetic solar features and disturbances in solar wind plasma parameters and it is seen that all the GLEs have been found to be associated with coronal mass ejections, hard X-ray solar flares and solar radio bursts. All the GLEs have also been found to be associated with sudden jumps in solar proton flux of energy of ${\geq}60Mev$. A positive correlation with correlation coefficient of 0.48 has been found between the maximum percentage intensity (Imax%) of Ground Level Enhancements and the peak value of solar proton flux of energy (${\geq}60Mev$). All the Ground Level Enhancements have been found to be associated with jumps in solar wind plasma velocity (JSWV) events. A positive correlation with correlation coefficient of 0.43 has been found between the maximum percentage intensity (Imax %) of Ground Level Enhancements and the peak value of solar wind plasma velocity of associated (JSWV) events. All the Ground Level Enhancements have been found to be associated with jumps in solar wind plasma pressure (JSWP) events. A positive correlation with correlation coefficient of 0.67 has been found between the maximum percentage intensity (Imax %) of Ground Level Enhancements and the peak value of solar wind plasma pressure of associated (JSWP) events and of 0.68 between the maximum percentage intensity (Imax %) of Ground Level Enhancements and the magnitude of the jump in solar wind plasma pressure of associated (JSWP) events.

• Toxicological Research
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• v.26 no.1
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• pp.21-28
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• 2010

As the frequency and the intensity of so called Asian dust (AD) events have increased, public concerns about the adverse health effects has spiked sharply over the last two decades. Despite the recent reports on the correlation between AD events and the risk for cardiovascular and respiratory disease, the nature of the toxicity and the degree of the risk are yet largely unknown. In the present study, we investigated the effects of the dichloromethane extract of AD (AD-X) and that of urban dust (NAD-X) collected during a non-AD period on gene expression in HL-60 cells using Illumina Sentrix HumanRef-8 Expression BeadChips. Global changes in gene expression were analyzed after 24 h of incubation with 50 or 100 ${\mu}g$/ml AD-X and NAD-X. By one-way analysis of variance (p < 0.05) and Benjamini-Hochberg multiple testing correction for false discovery rate of the results, 573 and 297 genes were identified as AD-X- and NAD-X-responsive, respectively. The genes were classified into three groups by Venn diagram analysis of their expression profile, i.e., 290 AD-X-specific, 14 NAD-X-specific, and 283 overlapping genes. Quantitative realtime PCR confirmed the changes in the expression levels of the selected genes. The expression patterns of five genes, namely SORL1, RABEPK, DDIT4, AZU1, and NUDT1 differed significantly between the two groups. Following rigorous validation process, these genes may provide information in developing biomarker for AD exposure.

• The Bulletin of The Korean Astronomical Society
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• v.37 no.1
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• pp.97-97
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• 2012

Hinode/XRT has observed coronal mass ejections (CMEs) since it launched on Sep. 2006. Observing programs of Hinode/XRT, called 'CME watch', perform several binned observations to obtain large FOV observations with long exposure time that allows the detection of faint CME plasmas in high temperatures. Using those observations, we determine the upper limit to the mass of hot CME plasma using emission measure by assuming the observed plasma structure. In some events, an associated prominence eruption and CME plasma were observed in EUV observations as absorption or emission features. The absorption feature provides the lower limit to the cold mass while the emission feature provides the upper limit to the mass of observed CME plasma in X-ray and EUV passbands. In addition, some events were observed by coronagraph observations (SOHO/LASCO, STEREO/COR1) that allow the determination of total CME mass. However, some events were not observed by the coronagraphs possibly because of low density of the CME plasma. We present the mass constraints of CME plasma and associated prominence as determined by emission and absorption in EUV and X-ray passbands, then compare this mass to the total CME mass as derived from coronagraphs.

• Journal of the Korean Statistical Society
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• v.23 no.2
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• pp.499-501
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• 1994

Let ${X_n}$ be conditionally i.i.d. given $g \subset \sigma(X_n, n \geq 1)$. We will prove that $g$ is degenerate if and only if ${X_n, n \geq 1}$ are i.i.d. random variable(r.v.s). As a corollary the Hewitt-Savage zero-one law is obtained using the fact that interchageable process is conditionally i.i.d. given the $\sigma$-algebra of permutable events.

• Reproductive and Developmental Biology
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• v.41 no.2
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• pp.33-40
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• 2017

X-chromosome inactivation is one of the most complex events observed in early embryo developments. The epigenetic changes occurred in female X-chromosome is essential to compensate dosages of X-linked genes between males and females. Because of the relevance of the epigenetic process to the normal embryo developments and stem cell studies, X-chromosome inactivation has been focused intensively for last 10 years. Initiation and regulation of the process is managed by diverse factors. Especially, proteins and non-coding RNAs encoded in X-chromosome inactivation center, and a couple of transcription factors have been reported to regulate the event. In this review, we introduce the reported factors, and how they regulate epigenetic inactivation of X-chromosomes.

• Journal of Wind Energy
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• v.15 no.1
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• pp.21-29
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• 2024

In order to respond to environmental changes and various events in the nearby sea area due to the operation of an offshore wind substantiation farm in the Southwest Sea, X-band radar has been installed and operated on a fixed platform since 2018. The X-band radar's monitoring system produces wave and current data through Rutter's Ocean WaveS wave and current (Sigma S6 WaMoS II). In this study, to verify the reliability of the produced data, the accuracy of current and wave data was evaluated by analyzing the correlation with the results obtained by an acoustic doppler current profiler (ADCP). The selected analysis period was a total of 30 days from November 29 to December 28, 2021, the period during which the ADCP survey was conducted. As a result of comparative verification, the current, wave height and peak wave period (H_s > 0.69 m) data observed from the X-band radar showed a high correlation with the results investigated from ADCP. In the future, current and wave data produced by X-band radar are expected to be used as basic data to analyze environmental changes in sea areas and provide information on various events.

• The Bulletin of The Korean Astronomical Society
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• v.37 no.2
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• pp.110.1-110.1
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• 2012

We studied the source regions of 12 solar energetic particle (SEP) events seen between 2010 August and 2012 January at STEREO-A, B and ACE, when the two STEREO spacecraft were separated by about $180^{\circ}$. All events were associated with strong flares (C1 - X6) and fast coronal mass ejections (CMEs) accompanied by type II radio bursts. We have determined the arrival times of the SEP events at the three spacecraft. EUV waves observed in $195{\AA}$ and $193{\AA}$ channels of STEREO and SDO/AIA are tracked across the Sun and the arrival time of the EUV wave at the photospheric source of open field lines extending to the spacecraft connection points at 2.5 Rsun estimated. We found 7 events with flux enhancements in all spacecraft and 4 in two spacecraft. Most events came from a single source. The results show that magnetic field connections between source regions and the spacecraft play an important role in abrupt flux enhancements. In the most cases, EUV waves at the Sun are associated with a wide longitudinal spread of the SEPs.

• The Research Journal of the Costume Culture
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• v.21 no.5
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• pp.726-741
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• 2013

Malling culture, which refers to the enjoyment of shopping in multi-complex malls with shopping, cultural, and leisure facilities, has emerged as a major trend in society. However, few studies have researched malling culture in depth. This study classified people who go to multi-complex shopping malls as belonging to the baby-boom generation, X-generation, or Y-generation to investigate consumer culture in malls, with an emphasis on user satisfaction and entertainment experiences. Consumers who had shopped in a multi-complex shopping mall during the last 6 months were surveyed. Data were collected through a research company, and responses from 417 subjects were used in the analysis. Among the 417 subjects, 130 were baby-boomers, 136 were from the X-generation, and 151 were from the Y-generation. Investigating the components of multi-complex shopping malls that stimulate entertainment experiences, this study found that exploratory, emotional, and leisure experiences were enhanced when users were more satisfied with the image, atmosphere, and events of shopping malls. In addition, mall image and atmosphere contributed to the improvement of social experiences. With regard to generation, baby-boomers and subjects from the X-generation were generally more satisfied with mall atmosphere, image, and events and had more exploratory and leisure experiences. This study holds significance in that it examined malling culture from a wider perspective than simply the younger generation and presented scholarly and marketing implications based on insights into generational malling culture.

• Journal of The Korean Astronomical Society
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• v.41 no.6
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• pp.181-186
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• 2008

Recently, Choe & Cheng (2002) have demonstrated that multiple magnetic flux systems with closed configurations can have more magnetic energy than the corresponding open magnetic fields. In relation to this issue, we have addressed two questions: (1) how much fraction of eruptive solar active regions shows multiple flux system features, and (2) what winding angle could be an eruption threshold. For this investigation, we have taken a sample of 105 front-side halo CMEs, which occurred from 1996 to 2001, and whose source regions were located near the disk center, for which magnetic polarities in SOHO/MDI magnetograms are clearly discernible. Examining their soft X-ray images taken by Yohkoh SXT in pre-eruption stages, we have classified these events into two groups: multiple flux system events and single flux system events. It is found that 74% (78/105) of the sample events show multiple flux system features. Comparing the field configuration of an active region with a numerical model, we have also found that the winding angle of the eruptive flux system is slightly above $1.5{\pi}$.

• Journal of The Korean Astronomical Society
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• v.38 no.4
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• pp.437-443
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• 2005

The Solar Radio Burst Locator (SRBL) is a spectrometer that can observe solar microwave bursts over a wide band (0.1-18 GHz) as well as detect the burst locations without interferometry or mechanical scanning. Its prototype has been operated at Owens Valley Radio Observatory (OVRO) since 1998. In this study, we have evaluated the capability of the SRBL system in flux and radio burst location measurements. For this, we consider 130 microwave bursts from 2000 to 2002. The SRBL radio fluxes of 53 events were compared with the fluxes from USAF/RSTN and the burst locations of 25 events were compared with the optical flare locations. From this study, we found: (1) there is a relatively good correlation (r = 0.9) between SRBL flux and RSTN flux; (2) the mean location error is about 8.4 arcmin and the location error (4.7 arcmin) of single source events is much smaller than that (14.9 arcmin) of multiple source events; (3) the minimum location error usually occurred just after the starting time of burst, mostly within 10 seconds; (4) there is a possible anti-correlation (r = -0.4) between the pointing error of SRBL antenna and the location error. The anti-correlation becomes more evident (r=-0.9) for 6 strong single source events associated with X-class flares. Our results show that the flux measurement of SRBL is consistent with that of RSTN, and the mean location error of SRBL is estimated to be about 5 arcmin for single source events.