• The Bulletin of The Korean Astronomical Society
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• v.42 no.2
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• pp.61.2-61.2
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• 2017

We report a fine scale transient brightening event near a pore boundary with the Fast Imaging Solar Spectrograph (FISS) of the 1.6m Goode Solar Telescope (GST), the Atmospheric Imaging Assembly (AIA) aboard the Solar Dynamics Observatory (SDO), and Helioseismic and Magnetic Imager (HMI) aboard SDO. The event appears in all AIA extreme ultraviolet bands, also in the two FISS lines, $H{\alpha}$ and Ca II $8542{\AA}$, and lasted for a minute. The brightening occurred at a footpoint of a loop. The conjugate brightening occurred at the other foot point outside the FISS field of view. The brightening near the pore exhibit a redshift of 4.3 km s-1 in the $H{\alpha}$ and about 2.3 km s-1 in Ca II line. Differential emission measure derived from 6 AIA EUV passbands and cloud model fitting of the two FISS lines indicate the temperature increase of between 10,000 and 20 MK at the main event. After the brightening, the upward mass motion appears in the AIA images. We discuss the physical implication of this brightening in the context of magnetic reconnection and coronal heating.

• The Bulletin of The Korean Astronomical Society
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• v.38 no.2
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• pp.91.1-91.1
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• 2013

Since 2010, we have improved the Fast Imaging Solar Spectrograph (FISS) and observed the Sun. From the early observations we noticed two instrumental problems: poorer spatial resolution due to chromatic aberration and lower light level in the Ca II band. We tried to overcome these problems in two ways. First, we updated the relay optics. With the new one, we don't find any noticeable chromatic aberration between Ha and CaII and as a result can obtain the high resolution data in Ca II as well. Second, we replaced mirrors and the grating. This resulted in the increase of light level by a factor of up to 2.5, and hence in the high S/N ratio. The images constructed from the recentest observations indicate that the performance of the FISS is now much closer to our original intention than at the beginning.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.27 no.5
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• pp.424-430
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• 2005

The oral cavity is humid environment mainly due to the continuous salivary flow. The reaction of oral mucosa to fluid flow is important for homeostasis and pathogenesis. The objective of this study is the screening the change of gene expression after the application of fluid induced shear stress (FISS) on the gingival fibroblast using cDNA microarray assay. The immortalized human gingival fibroblasts were grown and FISS was applied using a cone viscometer at a rotational velocity of 40 rpm, respectively for periods of 2 and 4 hours. The synthesis of cDNA was done from the extracted total RNA and cDNA microarray assay was done subsequently. The genes that showed over 1.6 in the Cy3/Cy5 or the Cy5/Cy3 value were regarded as genes influenced significantly by the FISS application ion (/M/>0.7). The " RUNX-1" was increased its expression in 2 hours group and " RUN and SH3 domain containing 1" was increased its expression in 4 hours group. The "CC020415", "cyclin L1", "interferon regulatory factor1", "early growth response 1", "immediate early response 2", and "immediate early response 3" genes were increased their expression in 2 and 4 hours after FISS application. In conclusion, we could find many genes that were probably related to the FISS application. Interestingly, most of them were placed in similar molecular pathways and these findings improve the reliability of chip data and usefulness in overall screening. From this experiment, we could find many items for further study and it will make improvement in the understanding of intracellular events in response to FISS.

• Publications of The Korean Astronomical Society
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• v.26 no.1
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• pp.45-54
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• 2011

KASI and Seoul National University developed the Fast Imaging Solar Spectrograph (FISS) as one of major scientific instruments for the 1.6 m New Solar Telescope (NST) and installed it in the Coude room of the NST at Big Bear Solar Observatory (BBSO) in May, 2010. The major objective of the FISS is to study the fine-scale structures and dynamics of plasma in the photosphere and chromosphere. To achieve it, the FISS is required to take data with a spectral resolution higher than $10^5$ at the spectrograph mode and a temporal resolution less than 10 seconds at the imaging mode. The FISS is a spectrograph using Echelle grating and has characteristics that can observe dual bands (H${\alpha}$ and CaII 8542) simultaneously and perform fast imaging using fast raster scan and two fast CCD cameras. In this paper, we introduce briefly the whole process of FISS development from the requirement analysis to the first observations.

• The Bulletin of The Korean Astronomical Society
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• v.42 no.2
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• pp.61.3-61.3
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• 2017

We have studied the high-resolution $H{\alpha}$ and Ca II $8542{\AA}$ line profiles of Ellerman Bombs (EBs) obtained with the Fast Imaging Solar Spectrograph (FISS) installed on the 1.6m Goode Solar Telescope (GST) in Big Bear Solar Observatory (BBSO). The FISS spectra of EBs are compared with synthetic profiles computed using RH non-LTE radiative transfer code and a set of 1D atmospheric models with local transient heating, the latter of which is modeled by varying local temperature enhancement in magnitude and height. We could reproduce each of the observed $H{\alpha}$ and Ca II line profiles separately with different atmospheric models, but not with a single atmospheric model. To fit the observed $H{\alpha}$ lines we often need much higher temperature enhancements than those needed for fitting Ca II lines. Possible causes for this temperature mismatch are briefly discussed.

• The Bulletin of The Korean Astronomical Society
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• v.35 no.1
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• pp.35.2-35.2
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• 2010

한국천문연구원은 미국 BBSO(Big Bear Solar Observatory)에 건설 중인 1.6 m NST(New Solar Telescope) 개발사업에 참여하고 있다. 고속태양영상분광기, FISS(Fast Imaging Solar Spectrograph)는 한국천문연구원과 서울대학교가 공동으로 개발하는 태양관측용 영상분광기로서, Echelle 회절격자를 분광소자로 사용하고 있다. FISS는 빠른 영상 스캐닝과 고속 CCD 카메라를 이용하여 동시에 두 파장을 관측할 수 있으며, NST의 적응광학계로부터 영상을 입력받기 때문에 회절한계에 가까운 분광영상을 얻을 수 있다. 본 연구에서는 FISS 제작을 위한 요구사항 분석, 분광기 구성과 광학설계, 구성품의 제작, 그리고 분광기의 성능검증을 위한 태양 시험관측 결과에 대해 소개한다.

• The Bulletin of The Korean Astronomical Society
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• v.36 no.2
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• pp.80.1-80.1
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• 2011

It is well known that chromospheric features are fine structured, short lived, and dynamic. Spectrograph-based observation have obvious advantage of getting physical properties of solar chromosphere than filter-based one. We developed and installed Fast Imaging Solar Spectrograph (FISS) attached on New Solar Telescope in Big Bear Solar Observatory. FISS have capabilities to take data with high time, spatial and spectral resolution at two wavelengths(Ha $6563{\AA}$ and CaII $8542{\AA}$) simultaneously. After FISS installation, we observed various chromospheric features : active regions, quiet regions, filaments/prominences and so on. As one of chromospheric studies, we analyzed solar prominences and got physical parameters by using simple radiative transfer modeling. The ranges of temperature and non-thermal velocities are found to be 7500-13000K and 5-11km/s, respectively.

• The Bulletin of The Korean Astronomical Society
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• v.36 no.1
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• pp.38.1-38.1
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• 2011

Bright rims are one of the most unknown part of a filament nowadays. Many models tried to explain the environments, but there is no commonly acceptable model. Many survey observations have been performed to find various characteristics of the bright rim statistically, but there was only one spectroscopic observation to understand phenomena of the bright rim. We observed a bright rim on June 25, 2010 using FISS installed in NST, Big Bear Solar observatory. FISS can obtain a couple of wavebands data simultaneously with short time cadence and fine resolution(~ 0.1", expected) with Adaptive Optics. By applying the cloud model, we found source function, optical thickness, temperature and non-thermal velocity of the region from the spectra of Ha and CaII 8542 lines. We discuss the physical implication of these measurements on the nature of bright rims of filaments.

• Archives of Craniofacial Surgery
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• v.21 no.5
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• pp.294-300
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• 2020

Background: Mandibular fractures are one of the most common types of facial fractures, the treatment of which can be delayed due to the severity of the trauma resulting in an increase of complications; thus, early evaluation of trauma severity at the time of visit is important. In South Korea, trauma patients are triaged and intensively treated in designated regional trauma centers. This study aimed to analyze the relationship between trauma severity and mandibular fracture patterns. Methods: A medical records review was performed on patients who visited the regional trauma center at our hospital for mandibular fracture between 2009 and 2018. Epidemiologic data and mandibular fracture patterns were analyzed and compared with the conventional facial injury severity scale (FISS). Results: Among 73 patients, 51 were classified as non-severe trauma patients and 22 as severe trauma patients. A higher trauma severity was associated with older age (odds ratio [OR], 1.164; 95% confidence interval [CI], 1.057-1.404) and lower risk was associated with fractures located in the angle (OR, 0.001; 95% CI, 0-0.022), condylar process (OR, 0.001; 95% CI, 0-0.28), and coronoid process (OR, 0.004; 95% CI, 0-0.985). The risk was lower when the injury mechanism was a pedestrian traffic accident (OR, 0.004; 95% CI, 0-0.417) or fall (OR, 0.004; 95% CI, 0-0.663) compared with an in-car traffic accident. Higher FISS (OR, 1.503; 95% CI, 1.155-2.049) was associated with a higher trauma severity. The proposed model was found to predict the trauma severity better than the model using FISS (p< 0.001). Conclusion: Age, location of mandibular fractures, and injury mechanism showed significant relationships with the trauma severity. Epidemiologic data and patterns of mandibular fractures could predict the trauma severity better than FISS.

• The Bulletin of The Korean Astronomical Society
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• v.38 no.2
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• pp.92.1-92.1
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• 2013

In this study, we examined chromospheric oscillation signatures in two solar active regions, a limb active region and a sunspot with a light bridge, observed by the Fast Imaging Solar Spectrograph (FISS) of the 1.6m New Solar Telescope (NST) at Big Bear Solar Observatory. The FISS is a slit spectrograph with a fast imaging capability and can observe the solar chromosphere in $H{\alpha}$ and Ca II $8542{\AA}$ bands simultaneously with high spectral resolutions. After dark and flat correction, we compensated for image rotation at the Coude focus and made image alignment. We estimated Doppler shifts over active regions using the bisector method and investigated the temporal and spatial fluctuations of Doppler shifts for some selected cases. And we obtain the power map by using the Lomb-Scargle periodogram technique to examine the oscillation power at different features. Finally, we will discuss our results and implications.