• Parasites, Hosts and Diseases
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• 제50권3호
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• pp.273-276
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• 2012

Migratory birds have been suspected as playing a central role in transmission of various trematodes, but few surveys have been undertaken in the Republic of Korea. In the present study, we describe new fauna of microphallid flukes in Korea. Two species of microphallids were found in the intestines of 2 migratory bird species, namely the red necked stints (Calidris ruficollis) and the terek sandpiper (Xenus cinereus), in a coastal area of Gunsan-si, Jeollabuk-do. The microphallids recovered from the latter were 451 ${\mu}m$ in length and 217 ${\mu}m$ in width, and the eggs were very small, 13 ${\mu}m$ by 8 ${\mu}m$. They had the characteristic extracecal vitellaria intruding into the median posttesticular area, belonging to Endocotyle incana. Another microphallids were discovered from both migratory birds, 417 ${\mu}m$ in length and 249 ${\mu}m$ in width. The cirrus was projecting into the genital atrium in form of male papilla, and bounded by a muscular flap, termed pseudogonotyl. They were identified as Spelotrema pseudogonotyla in consideration of the distinctive male papilla and pseudogonotyl. Besides these flukes, Maritrema obstipum and Gynaecotyla squatarolae also were recovered. This paper is in fact the first report on the presence of Spelotrema and Endocotyle in Korea.

• 대한수의학회지
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• 제50권1호
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• pp.71-74
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• 2010

A trematode species belonging to the genus Prosthogonimus (family: Prosthogonimidae) was collected in August, 2004 from the bursa of Fabricius of a single Little Grebe, Tachybaptus ruficollis, caught in Chuncheon, Korea. Five specimens were collected in total and fluke morphology was examined under using a light microscope. The average parasite size was 5.6 ${\times}$ 3.2 mm (length ${\times}$ width; based on 4 specimens). The genital pore was located on the anterior right margin of the oral sucker. The cirrus sac was strongly sinuous and extended beyond the intestinal bifurcation to the ventral sucker. The prepharynx was extremely short and the pharynx was small. The vitellaria consisted of 6 follicle bunches and extended from the ventral sucker to the posterior of the testes. Finally, the uterus filled the body cavity posterior to the testes. In addition, there were no heavy slings occurred anterior to the testes. Based on these morphological characteristics, the parasites were identified as P. cuneatus. The discovery of P. cuneatus within a Little Grebe constitutes a new host identification and a new geographical record. This is the first reported case of Prosthogonimus infection within wild birds in Korea.

• Parasites, Hosts and Diseases
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• 제23권2호
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• pp.230-235
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• 1985

The metacercariae of an echinostomatid fluke were detected from a freshwater 6sh, Odontobutis obscura interrupta caught from the Seom river system, Wonseong-gun, Kangwon-do, and experimentally infected into rats to obtain the adult worms for the species identification. A total of 32 metacercariae was detected from 10 fishes (27.8%) out of 36 O. obscura interrupta caught from the river. The average size of metacercariae was $153.4{\times}149.0{\;}{\mu}{\textrm{m}}$. Also, it was uniquely specific that thickened membrane was formed around the metacercarial cyst wall. The rats orally infected with those metacercariae were sacrificed 20 days after infection to get the adult worms. The mean length and width of the adult worms were 0.75 cm and 0.13 cm, respectively. The number of collar spines on circumoral disk was 26 to 28, and the end group spines at lateral sides of the oral sucker were 4 on each side. The echinostomatid flukes observed in this study were all identified as Echinostoma hortense according to the morphologies of the cirrus sac, ovary, vitellaria and testes of the adult worms and the shape of eggs. On the other hand, O. obscura interrupta is one of the fresh-water fish that are preferably eaten raw by the rural inhabitants. Although no human case of 5. hortense infection by eating O. obscura interrupta has been experienced yet, the possibility is strongly suggested in this study.

• 정보처리학회논문지A
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• 제16A권5호
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• pp.307-318
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• 2009

컴퓨터 그래픽스에서 구름과 같은 대기 현상을 모델링하고 렌더링하는 것은 그 복잡성과 규모, 편재성 등으로 인해 상당히 까다로운 연구과제들 중의 하나이다. 본 논문은 컴퓨터 게임이나 항공 시뮬레이션 분야에서 요구되는, 실시간에 처리될 수 있는 구름 모델링과 렌더링 방법을 제안한다. 제안하는 방법은 사용자가 직관적이고 대화형 편집 과정을 거쳐 권운, 층운, 적운 등의 다양한 형태를 생성할 수 있다. 또한, 메타볼과 계층적 구형 파티클을 사용하여, 세부 묘사를 자동으로 추가할 수 있다. 생성된 파티클들은 다중 순방향 산란과 이방성 산란을 고려하여 빌보드 방식으로 출력함으로써 실시간 처리가 가능하다.

• 대기
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• 제17권2호
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• pp.125-133
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• 2007

Cloud amount calculation algorithm was developed using MTSAT-1R satellite data. The cloud amount is retrieved at 5 km ${\times}$ 5 km over the Korean Peninsula and adjacent sea area. The algorithm consists of three steps that are cloud detection, cloud type classification, and cloud amount calculation. At the first step, dynamic thresholds method was applied for detecting cloud pixels. For using objective thresholds in the algorithm, sensitivity test was performed for TBB and Albedo variation with temporal and spatial change. Detected cloud cover was classified into 3 cloud types (low-level cloud, cirrus or uncertain cloud, and cumulonimbus type high-level cloud) in second step. Finally, cloud amount was calculated by the integration method of the steradian angle of each cloud pixel over $3^{\circ}$ elevation. Calculated cloud amount was compared with measured cloud amount with eye at surface observatory for the validation. Bias, RMSE, and correlation coefficient were 0.4, 1.8, and 0.8, respectively. Validation results indicated that calculated cloud amount was a little higher than measured cloud amount but correlation was considerably high. Since calculated cloud amount has 5km ${\times}$ 5km resolution over Korean Peninsula and adjacent sea area, the satellite-driven cloud amount could show the possibility which overcomes the temporal and spatial limitation of measured cloud amount with eye at surface observatory.

• Animal Systematics, Evolution and Diversity
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• 제27권3호
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• pp.228-238
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• 2011

Two urostyloid ciliates, collected from brackish water in Korea, were identified as Diaxonella pseudorubra pseudorubra (Kaltenbach, 1960) Berger, 2006 and Pseudokeronopsis flava (Cohn, 1866) Wirnsberger, Larsen and Uhlig, 1987. The description was based on living, protargol impregnated specimens. These species are described as follows: Diaxonella pseudorubra pseudorubra: body size in vivo $145-230{\times}40-60\;{\mu}m$, elongated ellipsoidal in shape. Cytoplasm reddish and flexible. Adoral zone of membranelles occupied 30-40% of the body; composed of 33-44 membranelles; 1-3 frontoterminal cirri, 1-4 frontal row cirri, 4-6 buccal cirri, 6-10 transverse cirri. Midventral rows composed of 14-24 cirri, four left marginal rows, one right marginal row. Two kinds of cortical granules; the larger one is yellowish and the smaller one is reddish. Pseudokeronopsis flava: body size in vivo $150-210{\times}30-45\;{\mu}m$, elongated ellipsoidal shape. Cytoplasm yellowish and flexible. Adoral zone of membranelles occupied 25-30% of body; composed of 44-58 membranelles in number. Frontal cirri forming bicorona composed of 5-7 cirral pairs, 2-3 frontoterminal cirri, one buccal cirrus, and 2-3 transverse cirri. Midventral rows composed of 18-33 cirri, 34-53 left marginal cirri, and 40-58 right marginal cirri. Two kinds of cortical granules; the larger one is colorless and "blood-cell-shaped," and the smaller one is yellowish. Diaxonella pseudorubra pseudorubra is different from the most similar subspecies, D. pseudorubra pulchra, in cytoplasmic color and number of midventral cirri. Pseudokeronopsis flava is different from its most similar congeners in pigment granular color, number of bicorona, number of midventral cirri, and position of the contractile vacuole.

• 한국항공우주학회지
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• 제44권12호
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• pp.1035-1042
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• 2016

상용 비행시뮬레이션 게임 엔진 X-Plane을 이용하여 구성한 비행시뮬레이터에 대해 FTD level 5를 만족시킬 수 있는 QTG작성에 대해 연구하였다. 모델은 Cirrus사(社)의 SR-20을 대상으로 하였다. QTG의 테스트항목 중에는 조종반력을 측정하는 항목도 있다. 따라서 Brunner사(社)의 CLS(Control Loading System)을 조종 장치에 설치하여 조종반력을 측정할 수 있도록 구성하였다. X-Plane은 자체적으로 트림루틴을 제공하지 않으므로 외부에서 Autopilot을 구성하여 항공기가 트림상태에 도달할 수 있도록 하였다. 또한 테스트를 자동으로 수행할 수 있는 알고리듬을 개발하여 수동으로 조종하여 테스트하는 번거로움을 피하고 같은 테스트를 같은 조건으로 진행할 수 있도록 하였다. FTD Level 5의 경우 실제 비행데이터가 아닌 alternative data source를 적용할 수 있으며 이를 활용하여 모든 테스트 결과가 주어진 범위를 만족하였다.

• Parasites, Hosts and Diseases
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• 제55권4호
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• pp.425-428
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• 2017

Human diphyllobothriasis is a parasitic disease caused by ingestion of larvae (plerocercoids) in raw or undercooked fish and commonly found in temperate areas. Rare cases were reported in tropical or subtropical areas especially in children. The first documented case of pediatric diphyllobothriasis in Taiwan had been reported 11 years ago. Here, we report another 8-year-old girl case who presented with a live noodle-like worm hanging down from her anus, with no other detectable symptoms. We pulled the worm out and found the strobila being 260 cm in length. Examination of gravid proglottids showed that they were wider than their lengths, containing an ovoid cirrus sac in the anterior side and the rosette-shaped uterus. Eggs extracted from the uterus were ovoid and operculated. Diphyllobothrium latum was confirmed by molecular analysis of the mitochondrial DNA cytochrome c oxidase subunit 1 (cox1) gene. The girl was treated with a single oral dose of praziquantel, and no eggs or proglottids were observed from her stool in the subsequent 3 months. The reemergence of human diphyllobothriasis in non-endemic countries is probably due to prevalent habit of eating imported raw fish from endemic areas. This pediatric case raised our concern that human diphyllobothriasis is likely underestimated because of unremarkable symptoms.

• Parasites, Hosts and Diseases
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• 제56권1호
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• pp.87-91
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• 2018

Morphological and molecular characteristics of spirometrid tapeworms, Spirometra decipiens, were studied, which were recovered from a heavily infected stray cat road-killed in Eumseong-gun, Chungcheongbuk-do (Province), the Republic of Korea (=Korea). A total of 134 scolices and many broken immature and mature proglottids of Spirometra tapeworms were collected from the small intestine of the cat. Morphological observations were based on 116 specimens. The scolex was 22.8-32.6 mm (27.4 mm in average) in length and small spoon-shape with 2 distinct bothria. The uterus was coiled 3-4 times, the end of the uterus was ball-shaped, and the vaginal aperture shaped as a crescent moon was closer to the cirrus aperture than to the uterine aperture. PCR amplification and direct sequencing of the cox1 target fragment (377 bp in length and corresponding to positions 769-1,146 bp of the cox1 gene) were performed using total genomic DNA extracted from 134 specimens. The cox1 sequences (377 bp) of the specimens showed 99.0% similarity to the reference sequence of S. decipiens and 89.3% similarity to the reference sequence of S. erinaceieuropaei. In the present study, we report a stray cat heavily infected with S. decipiens identified by mitochondrial cox1 sequence analysis and morphological examinations of the adult worms.

• Animal Systematics, Evolution and Diversity
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• 제28권3호
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• pp.168-177
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• 2012

Two stichotrichid ciliates, collected from marine waters in Jeju Island, were identified as Afroamphisiella multinucleata Foissner et al., 2002 and Pseudokahliella marina (Foissner et al., 1982) Berger et al., 1985. They are recorded for the first time in Korea. The descriptions are based on examinations of living as well as protargol-impregnated specimens. These species are characterized as follows. Afroamphisiella multinucleata has a body size in vivo of $70-95{\times}20-35{\mu}m$; elongate rectangular in shape; contractile vacuole located slightly above mid-body. The adoral zone is bipartited into 3 distal and 13-17 proximal membranelles and occupies 28-35% of the body length. The frontal row comprises 1-4 cirri and one buccal cirrus. The amphisiellid median cirral row is composed of 14-21 cirri, 10-19 left marginal cirri, and 21-30 right marginal cirri. Cortical granules are yellowish. 11-20 globular/ellipsoidal macronuclear nodules arrange proximally along the cell margins. Pseudokahliella marina has a body size in vivo of $110-195{\times}40-110{\mu}m$ and broadly elliptical in shape. The adoral zone of the membranelles occupies 50-60% of the body length, and is composed of 41-70 membranelles. A prominent frontal scutum is present. The contractile vacuole is located below the mid-body. There are 11-13 frontoventral rows, including marginal rows. Caudal cirri and transverse cirri are absent. Three invariable non-fragmented bipolar dorsal kineties are present. The left and right marginal rows are composed of 22-35 and 28-40 cirri, respectively. Colourless cortical granules are present. 8-11 spherical/ellipsoidal macronuclear nodules are connected with each other by thread-like tructures, forming an inverted C-shape.