• Title/Summary/Keyword: Fin

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Radix auricularia coreana: Natural snail host of Clinostomum complanatum in Korea (물달팽이 (Ranix auiricularia coreana) : 한국에서 새인두흡충의 제1중간숙주)

  • Jeong, Dong-Il;Gong, Hyeon-Hui;Ju, Jong-Yun
    • Parasites, Hosts and Diseases
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    • v.36 no.1
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    • pp.1-6
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    • 1998
  • An epidemiological survey was carried out to determine the first intermediate host of Clinostomum complanatum among freshwater snails in Korea. Two species of snails belonging to the family Lymnaeidae were collected in Kaum-ji (pond) , Uisong-gun, Kyongsangbuk-do. Twelve (0.9%) out of 1,273 Radiae auricularia corecna examined were found to liberate cercariae of C. complcnatum, which were identified by morphologital characteristics and experimental infections in freshwater fish, Pseunorosborc pnnjc. The cercariae were brevifurcate and clinostomatoid. They had a transparent dorsal fin, a well developed penetrating organ and a pair of eye spots. The body measured $119-147{\;}{\times}{\;}33-36{\mu\textrm{m}}$, tail stem, tailstem은 $275-370{\;}{\times}{\;}19-26{\;}{\mu\textrm{m}}$, and furcae, $72-104{\;}{\mu\textrm{m}}$. Rediae were demonstrated in the infected snail after crushing. Redia, $527-1,630{\;}{\mu\textrm{m}}$ long and 121-368${\;}{\mu\textrm{m}}$ wide, contained 10-45 germ balls and cercariae in various developmental stapes. The metacercariae recovered from fish experimentally infected with C. complanntum cercariae were morphologically identical to those from naturally infected fish.

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Air-side Heat Transfer and Pressure Drop of a Fin-and-Tube Heat Exchanger Under Low Temperature Condition (저온 조건에서 핀-관 열교환기의 공기측 열전달 및 압력손실)

  • Kim, Nae-Hyun
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.18 no.4
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    • pp.15-20
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    • 2017
  • Currently, residential air conditioners operate as a heat pump during winter. In this case, the outdoor heat exchanger acts as an evaporator obtaining heat from cold air. On the other hand, it acts as a condenser during summer transferring heat to hot air. The outdoor temperature changes significantly from high to low. Generally, the air-side j and f factors are obtained at a standard outdoor temperature. Therefore, the applicability of the j and f factors under different outdoor conditions needs to be checked. In this study, tests were conducted for a two-row louver finned heat exchanger changing the outdoor temperature to subzero. The effects of the tube-side brine flow rate were also checked. The results showed that air-side j and f factors were essentially constant and independent of the outdoor temperature, suggesting that an extension of j and f factors obtained under standard conditions to a low outdoor temperature is acceptable. All j and f factors agreed within 9% and 3%, respectively. Tests were also conducted by changing the coolant flow rate. Both the j and f factors did not change according to the flow rate, suggesting that the tube-side heat transfer correlation is acceptable.

An Implementation of an Edge-based Algorithm for Separating and Intersecting Spherical Polygons (구 볼록 다각형 들의 분리 및 교차를 위한 간선 기반 알고리즘의 구현)

  • Ha, Jong-Seong;Cheon, Eun-Hong
    • Journal of KIISE:Computer Systems and Theory
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    • v.28 no.9
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    • pp.479-490
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    • 2001
  • In this paper, we consider the method of partitioning a sphere into faces with a set of spherical convex polygons $\Gamma$=${P_1...P_n}$ for determining the maximum of minimum intersection. This problem is commonly related with five geometric problems that fin the densest hemisphere containing the maximum subset of $\Gamma$, a great circle separating $\Gamma$, a great circle bisecting $\Gamma$ and a great circle intersecting the minimum or maximum subset of $\Gamma$. In order to efficiently compute the minimum or maximum intersection of spherical polygons. we take the approach of edge-based partition, in which the ownerships of edges rather than faces are manipulated as the sphere is incrementally partitioned by each of the polygons. Finally, by gathering the unordered split edges with the maximum number of ownerships. we approximately obtain the centroids of the solution faces without constructing their boundaries. Our algorithm for finding the maximum intersection is analyzed to have an efficient time complexity O(nv) where n and v respectively, are the numbers of polygons and all vertices. Furthermore, it is practical from the view of implementation, since it computes numerical values. robustly and deals with all the degenerate cases, Using the similar approach, the boundary of a general intersection can be constructed in O(nv+LlogL) time, where : is the output-senstive number of solution edges.

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Study on the Relationship between the Tail Graphics of Various Airlines and National Branding Correspondence (항공사별 꼬리날개 그래픽과 국가브랜드 인지도 상관관계에 관한 연구)

  • Zhou, Dan;Seo, Han-Sok
    • The Journal of the Korea Contents Association
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    • v.19 no.10
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    • pp.21-31
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    • 2019
  • With the development of the aviation industry, aircraft painting design also plays the role of transmitting the national image while conveying the individual image of the airline. The recognition and recognition of the national image can be obtained by building a national brand. As a result, more and more companies are using the national brand image of their own country or other countries to add value to the company. Objective: To better reflect the national brand recognition for the design of the tail fin in the future aircraft painting design. This paper mainly studies the correlation between the tail graphic elements of aircraft painting design and national brand recognition based on the tail graphics of the three major airline alliance members. Based on the prior research, the relevant hypotheses were proposed and the questionnaire was designed. Secondly, a questionnaire survey was conducted on the passengers using the aircraft, and the correlation analysis was performed on the data by the SPSS regression analysis method. Conclusion: Data analysis has a strong correlation.

An Analysis about Impact of Smart Home manufacturing and service Industry on National Economy (스마트홈 제조업과 서비스업의 국민경제적 파급효과 분석)

  • Kim, Kyunam
    • Journal of Technology Innovation
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    • v.28 no.4
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    • pp.97-126
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    • 2020
  • This study evaluated its potentials by quantitatively analyzing the national economic impact of the smart home-related industry, which is attracting attention as a core industry of the 4th industrial revolution. For the analysis, the smart home-related industries were classified into manufacturing and service industries through a literature review of the previous studies. Using the 2018 input-output table, this paper analyzed linkage effects between industries as well as spillover effects in the production, value-added, employment and job. As a result, the smart home manufacturing and service sectors showed a higher spillover effect in value-added than other industries in each industrial field. In the smart home industry, the spillover effects of manufacturing sector to service sector are larger than those of service sector to manufacturing sector. Moreover, it was confirmed that smart home industry was highly related to not only the technology-intensive industry, but also the service sector for smart cities, smart cars, Fin-tech, and etc. On the other hand, the smart home manufacturing sector is a final demanding industry with relatively higher backward linkage effect than forward linkage effect. In the smart home service sector, the forward linkage effect was relatively high compared with the backward linkage effect, indicating that it was an industry with a high supply function to other industries.

First Record of the Smoothtail Mobula, Mobula thurstoni (Myliobatiformes: Myliobatidae) in Southern Korea (한국 여수에서 채집된 매가오리과 (Myliobatidae) 어류 첫기록종, Mobula thurstoni)

  • Myoung, Se Hun;Song, Young Sun;Kang, Chung-Bae;Choi, Hong-In;Kim, Jong-Gwan;Yoon, Moongeun;Im, Jaebok;Han, Dong-Jin
    • Korean Journal of Ichthyology
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    • v.33 no.2
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    • pp.148-154
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    • 2021
  • Two specimens (1770~1850 mm disc width) of Mobula thurstoni, belonging to the family Myliobatidae, order Myliobatiformes, were first collected from the central coast of the Southern Sea of Korea in September 2018. This species is characterized by an anterior margin of disc with double curvature, a white-tipped dorsal fin, and the absence of a caudal spine. This species is morphologically similar to Mobula kuhlii, but has an anterior margin of pectoral fins with a double curvature and the dorsal coloration is bluish black rather than white. In addition, M. thurstoni was well distinguished from M. kuhlii as determined by mitochondrial DNA 16S rRNA sequences with genetic distances ranging from 0.030 to 0.069. The Korean name 'Mae-kkeun-kko-li-jwi-ga-o-li' is proposed for the species M. thurstoni.

Occurrence of a Natural Intergeneric Hybrid between a Female Tanakia lanceolata and a Male Rhodeus pseudosericeus (Cypriniformes: Cyprinidae) in Daecheoncheon Stream Flowing into the Yellow Sea in the Republic of Korea (서해안 독립 하천 대천천에서 납자루 Tanakia lanceolata (♀)와 한강납줄개 Rhodeus pseudosericeus(♂)의 자연 속간잡종 출현)

  • Kim, Yong Hwi;Sung, Mu Sung;Yun, Bong Han;Bang, In-Chul
    • Korean Journal of Ichthyology
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    • v.33 no.2
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    • pp.45-56
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    • 2021
  • A male, presumed to be an intergeneric hybrid between Tanakia lanceolata and Rhodeus pseudosericeus, was collected in the Boryeong Daecheoncheon Stream flowing into the Yellow Sea in the Republic of Korea. Morphological and molecular phylogenetic analyses were performed to discriminate the definite origin of the estimated natural hybrid. As a result of the morphological analysis, the color of the dorsal and anal fin rays edges of the natural hybrid individual, the upper and lower body colors followed the morphological characteristics of T. lanceolata, and that blue longitudinal stripe in the center of the caudal peduncle, the incomplete lateral line, and the barbels absent followed the morphological characteristics of R. pseudosericeus. In addition, as a result of the cytochrome b (cytb) gene analysis of mitochondrial DNA (mtDNA), the natural hybrid showed a nucleotide sequence similarity of 99.82 to 100% with T. lanceolata, and the maternal species was identified as T. lanceolata. As a result of the recombination activating gene 1 (rag1) gene analysis of nuclear DNA (nDNA), the natural hybrid showed double peaks pattern reflecting both the single nucleotide polymorphism sites (38 bp) between T. lanceolata and R. pseudosericeus, and the paternal species was identified as R. pseudosericeus. Therefore, a natural hybrid estimated male of Acheilognathinae analyzed in this study was found to be an intergeneric hybrid between a female T. lanceolata and a male R. pseudosericeus.

Taxonomic Review of the Genus Saurida (Aulopiformes: Synodontidae) from Korea (한국산 매퉁이속(홍메치목, 매퉁이과) 어류의 분류학적 재검토)

  • Yeo, Minyu;Kim, JinKoo
    • Korean Journal of Ichthyology
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    • v.30 no.4
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    • pp.205-216
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    • 2018
  • Taxonomic review of the genus Saurida, belonging to the family Synodontidae, was conducted based on three species (S. macrolepis, S. microlepis and S. wanieso) collected from Korea between 1994 and 2017, and one species (S. elongata) loaned from Japan. S. wanieso can be readily distinguished from S. tumbil by following characteristics: outer palatine teeth (2 rows in S. wanieso vs. 3~4 rows in S. tumbil) and pectoral fin length (reaching to pelvic - dorsal line in S. wanieso vs. not reaching to pelvic - dorsal line in S. tumbil). In counts, the four Saurida spp. are well distinguished: number of lateral line scales (48~50 in S. macrolepis vs. 54~58 in S. wanieso vs. 61~62 in S. elongata vs. 63~70 in S. microlepis), vertebrae (47~49 in S. macrolepis vs. 51~53 in S. wanieso vs. 57~59 in S. elongata vs. 62~64 in S. microlepis). The present study suggests S. undosquamis and S. tumbil must be absent in Korean waters, and also S. elongata may be rare or absent in Korean waters. Here we use the Korean name, "tum-bil-mae-tung-i" for S. wanieso, following Yamada et al. (1995) who treated Korean S. tumbil as S. wanieso.

Anti-inflammatory effect of Euonymi Lignum Suberalatum in LPS-activated Raw 264.7 cells and CA-induced paw edema rat model (귀전우(鬼箭羽)의 in vitro 및 in vivo에서의 염증억제효과)

  • Jeon, Chang Kwon;Park, Sang Mi;Park, Chung A;Byun, Sung Hui;Kim, Sang Chan
    • Herbal Formula Science
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    • v.27 no.2
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    • pp.101-120
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    • 2019
  • PURPOSE : Euonymi Lignum Suberalatum (EL) is the stem fin of Euonymi alatus. In traditional Korean medicine, EL is used for treatment of uterine bleeding, metritis and static blood. Recently, many studies have reported several pharmacological effects of EL including anticancer, antimicrobial, antidiabetic activity, and anti-oxidative stress. However, the mechanisms underlying anti-inflammatory effects by the EL is not established. METHODS : To investigate anti-inflammatory effects of Euonymi Lignum Suberalatum Water (ELWE), Raw 264.7 cells were pre-treated with $10-300{\mu}g/mL$ of ELWE, and then exposed to $1{\mu}g/mL$ of LPS. Levels of NO, IL-6, $IL-1{\beta}$ and $TNF-{\alpha}$ were detected by ELISA kit. Expression of pro-inflammatory proteins were determined by immunoblot analysis. To evaluate the anti-inflammatory effect in vivo, rat paw edema volume, and expressions of COX-2 and iNOS proteins in carrageenan (CA)-induced rat paw edema model. RESULTS : NO production activated by LPS, was decreased by $30-300{\mu}g/mL$ of ELWE. Production of inflammatory mediators such as $TNF-{\alpha}$, ILs, $PGE_2$ were decreased by ELWE 100 and $300{\mu}g/mL$. In addition, ELWE reduced LPS-mediated iNOS and COX-2 expression. Moreover, ELWE increased $I-{\kappa}B{\alpha}$ expression in cytoplasm and decreased $NF-{\kappa}B$ expression in nucleus. In vivo study, ELWE reduced the increases of paw swelling, and expression of iNOS and COX-2 proteins in paw edema induced by CA injection. CONCLUSION : The results indicate that ELWE could inhibit the acute inflammatory response, via modulation of $NF-{\kappa}B$ activation. Furthermore, inhibition of rat paw edema induced by CA is considered as clear evidence that ELWE may be a useful source to treat acute inflammation.