KASINICS 광학계의 고스트 분석

이성호,육인수,진호,박수종,한정열,이대희,공경남,조승현,박영식,박장현,한원용,Lee, Sung-Ho,Yuk, In-Soo,Jin, Ho,Pak, Soo-Jong,Han, Jeong-Yeol,Lee, Dae-Hee,Kong, Kyung-Nam,Cho, Seung-Hyun,Park, Young-Sik,Park, Jang-Hyun,Han, Won-Yong 한국천문학회 2005 天文學論叢 Vol.20 No.1

The reimaging optics of the KASINICS (KASI Near Infrared Camera System) includes many transparent components like an entrance window, band-pass filters, and blocking filters. As observational targets or in-field background objects, bright stars may cause optical ghosts that can significantly degrade the system performance of the KASINICS. We estimated analytically the relative brightness of ghost components with respect to a point source and examined the effects of tilting optical components as a method of suppressing ghosts. We also performed numerical ray tracings including all the optical components and found the results are consistent with those of the analytic estimations. We conclude that the KASINICS will not suffer from significant ghost effects with appropriate anti-reflection coatings and fittings for the optical components.

TNF in Human Tuberculosis: A Double-Edged Sword

Yuk Jae-Min,Kim Jin Kyung,Kim In Soo,Jo Eun-Kyeong 대한면역학회 2024 Immune Network Vol.24 No.1

TNF, a pleiotropic proinflammatory cytokine, is important for protective immunity and immunopathology during Mycobacterium tuberculosis (Mtb) infection, which causes tuberculosis (TB) in humans. TNF is produced primarily by phagocytes in the lungs during the early stages of Mtb infection and performs diverse physiological and pathological functions by binding to its receptors in a context-dependent manner. TNF is essential for granuloma formation, chronic infection prevention, and macrophage recruitment to and activation at the site of infection. In animal models, TNF, in cooperation with chemokines, contributes to the initiation, maintenance, and clearance of mycobacteria in granulomas. Although anti-TNF therapy is effective against immune diseases such as rheumatoid arthritis, it carries the risk of reactivating TB. Furthermore, TNF-associated inflammation contributes to cachexia in patients with TB. This review focuses on the multifaceted role of TNF in the pathogenesis and prevention of TB and underscores the importance of investigating the functions of TNF and its receptors in the establishment of protective immunity against and in the pathology of TB. Such investigations will facilitate the development of therapeutic strategies that target TNF signaling, which makes beneficial and detrimental contributions to the pathogenesis of TB.

대용량 이미지 데이타를 위한 효율적인 고차원 색인 구조

육인희(In Hee Yuk),이석희(Seok Hee Lee),유재수(Jae Soo Yoo),조기형(Ki Hyung Cho) 한국정보과학회 2000 정보과학회논문지 : 데이타베이스 Vol.27 No.3

최근 컴퓨터와 통신 기술의 발달로 인하여 이미지 데이타에 대한 이용이 폭발적으로 증가해 왔다. 따라서 이를 효율적으로 검색할 수 있는 방법이 요구되었고, 다양한 색인방법들이 제안되었다. 그러나 기존의 방법들은 차원이 증가함에 따라 검색 성능이 급격히 저하되는 “차원의 저주(The Curse of Dimensions)" 문제를 해결하지 못하고 있다. 이 논문은 데이타를 벡터 근사치로 표현한 후 이를 트리 형태로 구성하여 ”차원의 저주” 문제를 해결하는 고차원 데이타를 위한 색인구조 AB(Approximate Bit)-트리를 제안한다. 이 논문에서 제안하는 AB-트리는 VA-파일과 K-D-B-트리 구조를 기반으로 하고 있다. AB-트리는 적은 비트를 이용하여 고차원 공간을 표현하기 위해 노드내의 모든 정보를 비트로 표현한다. 중간노드의 비트 형태 엔트리는 하위노드에 포함된 정보를 의미하고 있어 탐색을 효율적으로 수행할 수 있도록 한다. 또한 질의처리 성능을 높이기 위해 마지막 단말노드를 표현할 때 실제 데이타가 들어있는 영역만을 표현할 수 있도록 하는 방법을 제안한다. 실험을 통한 성능평가를 수행하여 기존의 방법보다 제안된 방법이 고차원 데이타에 대한 검색 성능이 우수함을 보이며 “차원의 저주” 문제를 해결함을 보인다. In recent, many image data have been used typically because of computer and communication development. Accordingly, the methods to efficiently search these data are required and many index structures have been proposed. However, the existing multi-dimensional index structures don't solve "the curse of dimensions" problem. The problem grows exponentially due to raise dimension. In the paper, we propose a new index structure, called AB(Approximate Bit)-tree for indexing large data set in high dimensional space that solves the problem. AB-tree is constructed after mapping data to vector approximate and based on VA-File and K-D-B-Tree. We use a few bits to present space information in node, so that the proposed index structures appear efficient search performance because of bit type of entry in internode. In order to improve search performance, we propose a method that present only live space in last Internal node. In order to justify the performance of the proposed structure, we compare the proposed index structure with VA-File through experiments. As a result, we show that our proposed index structure outperforms the existing index structures and solves "the curse of dimensions" problem.

STAR FORMATION HISTORY AND CHEMICAL EVOLUTION OF THE SEXTANS DWARF SPHEROIDAL GALAXY

Lee, Myung Gyoon,Yuk, In-Soo,Park, Hong Soo,Harris, Jason,Zaritsky, Dennis IOP Publishing 2009 The Astrophysical journal Vol.703 No.1

<P>We present the star formation history (SFH) and chemical evolution of the Sextans dSph galaxy as a function of a galactocentric distance. We derive these from the VI photometry of stars in the 42' x 28' field using the SMART model developed by Yuk & Lee and adopting a closed-box model for chemical evolution. For the adopted age of Sextans 15 Gyr, we find that >84% of the stars formed prior to 11 Gyr ago, significant star formation extends from 15 to 11 Gyr ago (similar to 65% of the stars formed 13-15 Gyr ago, while similar to 25% formed 11-13 Gyr ago), detectable star formation continued to at least 8 Gyr ago, the SFH is more extended in the central regions than the outskirts, and the difference in star formation rates between the central and outer regions is most marked 11-13 Gyr ago. Whether blue straggler stars are interpreted as intermediate-age main-sequence stars affects conclusions regarding the SFH for times 4-8 Gyr ago, but this is at most only a trace population. We find that the metallicity of the stars increased rapidly up to [Fe/H] = -1.6 in the central region and to [Fe/H] = -1.8 in the outer region within the first Gyr, and has varied slowly since then. The abundance ratios of several elements derived in this study are in good agreement with the observational data based on the high-resolution spectroscopy in the literature. We conclude that the primary driver for the radial gradient of the stellar population in this galaxy is the SFH, which self-consistently drives the chemical enrichment history.</P>

Antiviral efficacy of oseltamivir against avian influenza virus in avian species.

Lee, Dong-Hun,Lee, Yu-Na,Park, Jae-Keun,Yuk, Seong-Su,Lee, Jae-Won,Kim, Jong-In,Han, Jin Soo,Lee, Joong-Bok,Park, Seung-Yong,Choi, In-Soo,Song, Chang-Seon American Association of Avian Pathologists [etc.] 2011 Avian diseases Vol.55 No.4

<P>Avian influenza is one of the most contagious viral diseases in bird species and, increasingly, interspecies transmission to mammalian species has been reported. Prevention and eradication of avian influenza virus (AIV) infection in birds may require vaccines as part of a comprehensive program including biosecurity, culling, diagnostics, and surveillance. However, for valuable bird species in zoos, novel eradication strategies are needed, including antiviral treatments. The present study evaluated the anti-influenza efficacy of the potent neuraminidase inhibitor oseltamivir in avian species using the orders Galliformes (chickens) and Anseriformes (ducks). Viral replication of low pathogenic AIV was significantly reduced in the chicken model and completely reduced in the duck model. Anti-influenza drug administration to valuable bird species with an appropriate extrapolation approach could be useful for control of AIV in combination with active surveillance and vaccination strategies. Further, evaluation of oseltamivir against highly pathogenic avian influenza (HPAI) using avian models would be needed to optimize the oseltamivir application guideline for HPAI control.</P>

Fluorescent H₂Emission Lines from the Reflection Nebula NGC 7023 Observed with IGRINS

Le, Huynh Anh N.,Pak, Soojong,Kaplan, Kyle,Mace, Gregory,Lee, Sungho,Pavel, Michael,Jeong, Ueejeong,Oh, Heeyoung,Lee, Hye-In,Chun, Moo-Young,Yuk, In-Soo,Pyo, Tae-Soo,Hwang, Narae,Kim, Kang-Min,Park, C American Astronomical Society 2017 The Astrophysical journal Vol.841 No.1

<P>We have analyzed the temperature, velocity, and density of H-2 gas in NGC. 7023 with a high-resolution near-infrared spectrum of the northwestern filament of the reflection nebula. By observing NGC. 7023 in the H and K bands at R similar or equal to 45,000 with the Immersion GRating INfrared Spectrograph, we detected 68 H-2 emission lines within the 1 '' x 15 '' slit. The diagnostic ratio of 2-1 S(1)/1-0 S(1) is 0.41-0.56. In addition, the estimated ortho-to-para ratio (OPR) is 1.63-1.82, indicating that the H-2 emission transitions in the observed region arise mostly from gas excited by UV fluorescence. Gradients in the temperature, velocity, and OPR within the observed area imply motion of the photodissociation region (PDR) relative to the molecular cloud. In addition, we derive the column density of H-2 from the observed emission lines and compare these results with PDR models in the literature covering a range of densities and incident UV field intensities. The notable difference between PDR model predictions and the observed data, in high rotational J levels of v = 1, is that the predicted formation temperature for newly formed H-2 should be lower than that of the model predictions. To investigate the density distribution, we combine pixels in 1 '' x 1 '' areas and derive the density distribution at the 0.002 pc scale. The derived gradient of density suggests that NGC 7023 has a clumpy structure, including a high clump density of similar to 10(5) cm(-3) with a size smaller than similar to 5 x 10(- 3) pc embedded in lower-density regions of 10(3)-10(4) cm(-3).</P>

Isolation and characterization of a novel H9N2 influenza virus in Korean native chicken farm.

Lee, Yu-Na,Lee, Dong-Hun,Park, Jae-Keun,Lim, Tae-Hyun,Youn, Ha-Na,Yuk, Seong-Su,Lee, Youn-Jeong,Mo, In-phil,Sung, Haan-Woo,Lee, Joong-Bok,Park, Seung-Yong,Choi, In-Soo,Song, Chang-Seon American Association of Avian Pathologists [etc.] 2011 Avian diseases Vol.55 No.4

<P>An outbreak of avian influenza, caused by an H9N2 low-pathogenic avian influenza virus (AIV), occurred in a chicken farm and caused severe economic losses due to mortality and diarrhea. AIV was isolated and identified in a sample from an affected native Korean chicken. Genetic analysis of the isolate revealed a high sequence similarity to genes of novel reassortant H9N2 viruses isolated from slaughterhouses and live bird markets in Korea in 2008 and 2009. Animal challenge studies demonstrated that the replication kinetics and pathogenicity of the isolate were considerably altered due to adaptation in chickens. Vaccine protection studies indicated that commercial vaccine was not able to prevent virus shedding and clinical disease when chickens were challenged with the isolate. These results suggest that the novel H9N2 virus possesses the capacity to replicate efficiently in the respiratory system against vaccination and to cause severe disease in domestic chickens. The results also highlight the importance of appropriate updating of vaccine strains, based on continuous surveillance data, to prevent the possibility of a new H9N2 epidemic in Korea.</P>

On the method of determining the star formation history from CMDs II. Application to M33

Yuk, In-Soo,Lee, Myung Gyoon,Kim, Minsun 한국천문학회 2001 天文學會報 Vol.26 No.2

On the method of determining the star formation history from CMD

In-Soo Yuk,Myung Gyoon Lee 한국천문학회 2001 天文學會報 Vol.26 No.1

A Software for Curvature Sensing Technique, KAOCST

In-Soo Yuk,Han In-Woo,Moon Il-Kweon 한국천문학회 1993 天文學會報 Vol.18 No.-