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Development progress in the Maunakea Spectroscopic Explorer's Exposure Time Calculator (MSE-ETC)

  • Kim, Taeeun;Kim, Changgon;Ji, Tae-Geun;Ahn, Hojae;Yang, Mingyeong;Pak, Soojong;Hong, Sungwook E.;Sobeck, Jennifer;Szeto, Kei;Marshall, Jennifer;Surace, Christian
    • 천문학회보
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    • 제46권2호
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    • pp.75.1-75.1
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    • 2021
  • MSE (Maunakea Spectroscopic Explorer)는 11.25m 구경의 망원경과 최대 4,000 개의 천체를 한 번에 관측할 수 있는 분광기를 통해 다천체 분광학 연구를 이끌 차세대 관측기기이다. 경희대학교는 망원경에 장착되는 다천체 분광기의 성능 요구사항을 바탕으로 노출 시간 소프트웨어 ETC (Exposure Time Calculator)를 개발하고 있다. ETC는 대기에 의한 연속선 소광, 방출선과 흡수선, 망원경 및 광학 기기의 투과율, 검출기의 암전류와 읽기 잡음을 바탕으로 신호 대 잡음비 S/N (Signal to Noise)을 도출하여 천체를 분광 관측하기 위한 적절한 노출 시간을 계산한다. MSE-ETC는 저분산 LR (Low Resolution, R=3,000), 중분산 MR (Moderate Resolution, R =6,000) 및 고분산 HR (High Resolution, R=40,000)의 관측 모드로 가시광선과 근적외선 영역의 S/N과 파장, 그리고 S/N과 AB등급 간의 상관관계를 보여준다. 본 포스터에서는 개발 중인 MSE-ETC 프로그램의 구조와 작동 알고리즘 및 사용 예를 발표한다.

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의령 입산마을의 중층적 경관 특성 (A Study on the Over-layered Landscape Characteristics of Ipsan Village, Uiryeong Area)

  • 임의제;소현수;배수현
    • 농촌계획
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    • 제24권1호
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    • pp.113-127
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    • 2018
  • This study comprehends that the landscape of Ipsan Village is the accumulated output of the landscape management and social behavior by the historic personages through the reference research and field surveys. And the study sorted out the over-layered landscape characteristics of Ipsan Village by analyzing the dispersed landscape elements as follows. First, right before the start of Japanese invasions to Korea(1592-98), Tamjin(耽津) An(安) Family moved into Ipsan and started establishing the a single clan village. At a site with mountain background and facing the water(背山臨水), the village used to be a typical farming one with an organically planned road-system and housing area following the traditional order. However, the landscape has changed drastically since the 20th century with the construction of banks, roads and readjustment of arable land etc. Second, the original landscape, which can be figured out through the 'Gosanjaesibyukgyeong(高山齋十六景)' in the 18th century, shows its harmony with natural landscape: mountain & valley, stream & field, traditional trees, etc, cultural landscape: village, well, spring, etc, and momentary landscape: seasons, time, weather phenomena, sound, behavior, etc. Third, based on the second, 16 natural landscape elements: mountain & stream, planting, etc. and 25 cultural landscape elements: housing spaces, self-cultivation & ceremony spaces, community spaces and modern education & enlightenment spaces were selected and interpreted as landscaping meanings. Fourth, the over-layered landscape which stems from the compositive functions and inter-connectivity of landscape elements which consists Ipsan Village is regarded as 'Natural geographical and Fungsu landscape', 'Rural production and livelihood landscape', 'Confucian ceremony and symbolic landscape' and 'Modern education and enlightenment landscape.'

Food Organisms of Fingerlings of Acentrogobius elongata Inhabited at Intertidal Zone of the Western Coast of Korea

  • Kim, Jong-Yeon;Jo, Soo-Gun;Yoon, Jong-Man
    • 한국양식학회:학술대회논문집
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    • 한국양식학회 2003년도 추계학술발표대회 논문요약집
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    • pp.93-94
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    • 2003
  • To investigate the food organisms of the Acentrogobius elongata during the juveniles stage, the stomach contents of fish, captured in the intertidal zone of Chungchongnam-do Sochon-gun Su-myon Dodun-ri between on early in June from the end of May 2000, were observed. Total length of the fingerings of A. elongata was 1.0~3.0cm size, and the participation rate of feeding was 68.6%. Main food organisms were such as copepods, shrimp larvae, polychaete larvae, and these occupied more than dry weight 4%. Copepods among them dominated the most quantitys by average 64.6%, and food organismsms appeared by order of polychaete larvae and shrimp larvae etc.. Therefore, most important food organisms of fingerlings stage of A. elongata were copepods, polychaete larvae, shrimp larvae etc.

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YBCO의 특성분석에 있어서 불순물효과의 보정 (Correction of lmpurity Effects on the Characterization of YBCO)

  • 하동한;변순예;김용일;한기열;이규원
    • 한국초전도학회:학술대회논문집
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    • 한국초전도학회 1999년도 High Temperature Superconductivity Vol.IX
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    • pp.171-174
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    • 1999
  • We have characterized solid solution Y$_{l-x}Ca_xBa_2Cu_3O_y$ (0${\le}$x${\le}$0.3) materials by measuring the XRD pattern, resistivity and hole concentrations, etc. As Ca concentration increases, T$_c$, is decreased monotonically because the hole concentration on the superconducting plane increases beyond the optimum region in the electronic phase diagram due to the hole transfer from the Cu-O chain to the CuO$_2$ plane. A very small amount of secondary phase have large effects on the analysis of oxygen content and hole concentration etc. The results before the correction of impurity phase are compared with those after the correction.

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고본뿌리의 정유성분 (The Essential Oils of Ligusticum tenuissimum Roots)

  • 육창수;강찬구;인문교;김경옥;김종우
    • 약학회지
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    • 제41권2호
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    • pp.273-276
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    • 1997
  • Ligusticum tenuissimum belongs to Umbelliferae, and its root is generally used in headache, common cold and arthralgia L. We have extracted and isolated butylidene phthal ide, 3-butylidene-4,5-dihydrophthalide of phthalide group and l-limonene, etc. of terpenoid group from the root by ordinary method. In Ligusticum sinense, L. jeholense, L. tenuissimum, L. jeholense var. tenuisectum, and L. officinale etc., the components of cnidilide, ligustilide of phthalide group are common features and specific constituents in genus Ligusticum. Therefore comparing that there is no phthalide group in genus Angelica, we think it is able to classify the difference of genus between Ligusticum and Angelica of Umbelliferae in chemotaxonomy.

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Food Organisms of Juveniles of Tridentiger of trigonocephalus Inhabited at Intertidal Zone of the Western Coast of Korea

  • Kim, Jong-Yeon;Jo, Soo-Gun;Yoon, Jong-Man
    • 한국양식학회:학술대회논문집
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    • 한국양식학회 2002년도 춘계 한국양식학회 학술대회 발표요지
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    • pp.225-226
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    • 2002
  • To investigate the food organisms of the Tridentiger trigonocephalus during the juveniles stage, the stomach contents of fish, captured in the intertidal zone of Chungchongnam-do Sochon-gun Su-myon Dodun-ri getween on early June from end of May 1999, were observed. Total length of the juveniles of T. trigonocephalus was 5.5mm∼9.0mm size, and the participation rate of feeding was 68.5%. Main food organisms were such as copepods, shrimp larvae, polychaete larvae, and these occupied more than dry weight 2%. Copepods among them dominated the most quantitys by average 67.5%, and next, food organismsms appeared much by order of polychaete larvae and shrimp larvae etc.. Therefore, most important food organisms of juvenile stage of T. trigonocephalus were copepods, polychaete larvae, shrimp larvae etc.

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A Hybrid Texture Coding Method for Fast Texture Mapping

  • Cui, Li;Kim, Hyungyu;Jang, Euee S.
    • Journal of Computing Science and Engineering
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    • 제10권2호
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    • pp.68-73
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    • 2016
  • An efficient texture compression method is proposed based on a block matching process between the current block and the previously encoded blocks. Texture mapping is widely used to improve the quality of rendering results in real-time applications. For fast texture mapping, it is important to find an optimal trade-off between compression efficiency and computational complexity. Low-complexity methods (e.g., ETC1 and DXT1) have often been adopted in real-time rendering applications because conventional compression methods (e.g., JPEG) achieve a high compression ratio at the cost of high complexity. We propose a block matching-based compression method that can achieve a higher compression ratio than ETC1 and DXT1 while maintaining computational complexity lower than that of JPEG. Through a comparison between the proposed method and existing compression methods, we confirm our expectations on the performance of the proposed method.

Mitochondrial Efficiency-Dependent Viability of Saccharomyces cerevisiae Mutants Carrying Individual Electron Transport Chain Component Deletions

  • Kwon, Young-Yon;Choi, Kyung-Mi;Cho, ChangYeon;Lee, Cheol-Koo
    • Molecules and Cells
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    • 제38권12호
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    • pp.1054-1063
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    • 2015
  • Mitochondria play a crucial role in eukaryotic cells; the mitochondrial electron transport chain (ETC) generates adenosine triphosphate (ATP), which serves as an energy source for numerous critical cellular activities. However, the ETC also generates deleterious reactive oxygen species (ROS) as a natural byproduct of oxidative phosphorylation. ROS are considered the major cause of aging because they damage proteins, lipids, and DNA by oxidation. We analyzed the chronological life span, growth phenotype, mitochondrial membrane potential (MMP), and intracellular ATP and mitochondrial superoxide levels of 33 single ETC component-deleted strains during the chronological aging process. Among the ETC mutant strains, 14 ($sdh1{\Delta}$, $sdh2{\Delta}$, $sdh4{\Delta}$, $cor1{\Delta}$, $cyt1{\Delta}$, $qcr7{\Delta}$, $qcr8{\Delta}$, $rip1{\Delta}$, $cox6{\Delta}$, $cox7{\Delta}$, $cox9{\Delta}$, $atp4{\Delta}$, $atp7{\Delta}$, and $atp17{\Delta}$) showed a significantly shorter life span. The deleted genes encode important elements of the ETC components succinate dehydrogenase (complex II) and cytochrome c oxidase (complex IV), and some of the deletions lead to structural instability of the membrane-$F_1F_0$-ATP synthase due to mutations in the stator stalk (complex V). These short-lived strains generated higher superoxide levels and produced lower ATP levels without alteration of MMP. In summary, ETC mutations decreased the life span of yeast due to impaired mitochondrial efficiency.

Antimelanogenic and antioxidant effects of trimethoxybenzene derivatives: methyl 3,4,5-trimethoxybenzoate, ethyl 3,4,5-trimethoxybenzoate, methyl 3,4,5-trimethoxycinnamate, and ethyl 3,4,5-trimethoxycinnamate

  • Jaewon Shin;Harim Lee;Seunghyun Ahn;Won Seok Jeong;CheongTaek Kim;Seyeon Park
    • Journal of Applied Biological Chemistry
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    • 제65권4호
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    • pp.299-306
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    • 2022
  • In this study, derivatives of trimethoxybenzene were investigated as inhibitors of melanogenesis. We examined the effects of methyl 3,4,5-trimethoxybenzoate (MTB), ethyl 3,4,5-trimethoxybenzoate (ETB), methyl 3,4,5-trimethoxycinnamate (MTC), and ethyl 3,4,5-trimethoxycinnamate (ETC). First, the inhibitory effects of these agents on melanin production were evaluated using α-melanocyte-stimulating hormone (α-MSH)-stimulated B16F10 melanoma cells. We found that all derivatives decreased α-MSH-induced melanin production in B16F10 melanoma cells; ETC showed a strong inhibitory effect at half of the concentration of the other derivatives. As tyrosinase is considered a key enzyme of melanogenesis, we also examined whether the derivatives inhibited tyrosinase activity. MTC and ETC reduced mushroom tyrosinase activity and expression levels of α-MSH-induced B16F10 cellular tyrosinase protein. Inhibitory effects of all derivatives on α-MSH-induced B16F10 cellular tyrosinase activity were shown in a dose-dependent manner. Additionally, the derivatives were exposed to diphenylpicrylhydrazyl free radical to examine their antioxidant characteristics. All derivatives showed considerable antioxidant activity, which was 2-fold higher than that of arbutin. In conclusion, the trimethoxybenzene derivatives, including MTB, ETB, MTC, and ETC exerted anti-melanogenic and antioxidant effects on α-MSH-stimulated melanogenesis, demonstrating their potential for use as novel hypopigmenting agents and antioxidants.

우유 및 유제품 중 잔류항생물질 분석법에 대한 연구 (Overview of Analytical Methods for Detection of Antibiotics in Milk and Dairy Products)

  • 김현욱;김기환;설국환;오미화;박범영
    • Journal of Dairy Science and Biotechnology
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    • 제31권1호
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    • pp.59-65
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    • 2013
  • Antibiotic residues are undesirable in milk and milk products for a number of reasons. In particular, they can have harmful effects on public health and harm to the manufacturer of the cultured milk products, e.g. MRSA etc. Although government regulatory agencies and the dairy industry have been successful in decreasing the presence of high concentrations of antibiotic residues, violations still occur and lead to contaminated products. As a result, several rapid and reliable methods for the detection of antibiotic residues have been developed, including microbiological and instrumental analysis methods. The conventional methods are time consuming, but recent improvements have allowed for better detection time, sensitivity, and accuracy. An example of an advanced detection instrument is the biosensor, which has several applications in food and environmental science, e.g. food-born pathogen detection, antimicrobial residues etc. In the present review, the recent trends in the methods used to test for antibiotic residues in milk and dairy products, as well as their specific applications, have been discussed.

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