• The Korean Journal of Soil Zoology
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• v.4 no.2
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• pp.89-100
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• 1999

Four new and a known spacies of the order Mononchida were described and illustrated. Iotonchus obtusus sp. n. was 2.8 mm long, a=33, b=4.2, c=61, V=68%, buccal cavity=61${\times}$45 mm, and is characterized by having basally situated dorsal tooth, presence of vulval papillae and in having short, hemispherical tail with thick cuticle at terminus. Miconchus vulvapapillatum sp. . was 2.7-3.6 mm long, a=29-36, b=4.1-4.5, c=18.4-21, V=65-69%, buccal cavity=53-61${\times}$29-33 mm, spicules=132-137 mm, ventromedian supplements 28-31, and was characterized by having 5-8 pre- and post vulval papillae in contiguous series, and three pairs of vulval glands. Clarkus koreanus sp. n. was 1.1-1.3 mm long, a=27.5-28.8, b=3.5-3.9, c=12-14.5, V=60-64%, buccal cavity=24-28${\times}$13.5-15 mm, and was characterized by well offset lip region, amphids situated well below to dorsal tooth apex, and vulva elevated, with vulval flap. Coomansus ulsani sp. n. was 1.2-1.5 mm long, a=23.5-26, b=3.4-3.8, c=13.6-14.8, V=65-68%, buccal cavity=36-39${\times}$21-23 mm and was characterized by well offset lip region and a thin longitudinal ridge on vertical walls of stoma.

• Journal of Korea Port Economic Association
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• v.36 no.4
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• pp.93-106
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• 2020

Trade is an important economic activity. In particular, since the establishment of the World Trade Organization (WTO), the scope of trade has been expanding due to events such as the entry of China into the WTO in 2001, the establishment of a multilateral trading system, mitigation and integration of trade barriers, and the establishment of the free trade agreement (FTA). Despite the expansion of the trade market, however, extreme events such as the 2008 global financial crisis, the 2016 Brexit, and the 2018 US-China trade war have had a direct negative impact on the trade market. Therefore, the present this study analyzed the dependence structure between the international shipping freight rate index, a variable representing trade activities, and the trade uncertainty between the US and China. The following is a summary of the analysis results. First, the US-Chinese trade policy uncertainty and international shipping freight rate index presented a Frank copula and rotated Clayton copula 270° distribution, respectively, showing the same distribution structure for each country. Second, the Kendall's tau correlation revealed a negative dependence between the international shipping freight rate index and US-Chinese trade policy uncertainty. The degree of dependence was greater in the combination of uncertainty in China's trade policy and international shipping freight rates. In other words, the dependence of global demand and trade policy uncertainty confirmed that China was stronger than the US. Finally, the tail dependence results revealed that the US-Chinese trade policy uncertainty and international shipping freight rates were independent of each other. This means that extreme events related to the trade policy uncertainty or international shipping rate index were not affected by each other.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.47 no.7
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• pp.489-498
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• 2019

The airloads and structural loads of Light Civil Helicopter (LCH) rotor are investigated using a loose CFD/CSD coupling. The structural dynamics model for LCH 5-bladed rotor cwith elastomeric bearing and inter-bladed damper is constructed using CAMRAD-II. Either isolated rotor or rotor-fuselage model is used to identify the effect of the fuselage on the aeromechanics behavior at a cruise speed of 0.28. The fuselage effect is shown to be marginal on the aeromechanics predictions of LCH rotor, though the effect can be non-negligible for the tail structure due to the prevailing root vortices strengthened by the fuselage upwash. A lifting-line based comprehensive analysis is also conducted to verify the CFD/CSD coupled analysis. The comparison study shows that the comprehensive analysis predictions are generally in good agreements with CFD/CSD coupled results. However, the predicted comprehensive analysis results underestimate peak-to-peak values of blade section airloads and elastic motions due to the limitation of unsteady aerodynamic predictions. Particularly, significant discrepancies appear in the structural loads with apparent phase differences.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.8
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• pp.149-155
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• 2019

This study aims to provide basic data for investigating the phenotypic traits and growth characteristics of Korean native black goats. The Jangsu and Tongyoung strains were shown to have black hair, while the Dangjin strain was shown to have black or dark brown long hair. Only the Tongyeong strain was found to have no wattle and one goat each from the females and males of the Dangjin strain was found to have no horns. The lengths of the ears and tails were similar for the female and male goats, while the lengths of horns and beards were longer in the male goats. The birth weight was 2 kg on average, with that of male goats tending to be slightly heavier than that of the females. Weights at the weaning period were found to be slightly heavier for the males. Also, at 12 months, the weights of the male goats by strain were shown to be heavier than that of the females. The body length and depth by strain were found to be higher for the male goats, while no differences in the chest width and girth between the strains or gender were found. These findings are expected to be used as a basis for differentiating between native and crossbred Korean black goat strains and for improving Korean native black goats.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2019.04a
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• pp.25-25
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• 2019

1953년 7월 27일 정전협정 이후 한반도를 가로지르는 DMZ (Demilitarized zone: 비무장지대)가 설정되었다. DMZ에 출입은 군사정전위원회의 허가가 있어야 가능하기에 군사시설 및 군작전지역을 포함하여 DMZ 및 민간인통제선 이북은 민간인 접근의 제한으로, 단절된 공간으로 변모하였다. DMZ는 우리나라의 대표적인 동고서저의 지형 및 다양한 생태환경을 두루 갖추고 있어 중요한 생태적 요충지로 평가받고 있다. 산림지역은 민간인통제지역까지 합치면 40여개의 산지가 분포하고 있으며, 하천은 크게 15개의 크고 작은 하천이 위치하고 있다. 남방한계선 수계를 따라 일부지역들은 하천 배후습지, 묵논습지 등 습원형태로도 많이 발견되고 있다. 이런 습원지역들은 대부분 미확인 지뢰지대로 접근이 제한적인 만큼 지난 세월의 흔적들을 고스란히 담고 있다. 1965년 한국자연보존연구회는 30여명의 국내학자를 동원하여 서울에서 가까운 DMZ 인접지역에 대한 예비적인 학술조사를 실시하였으며, 이를 계기로 1966년 10월부터 1968년 9월까지 2년간에 걸쳐 한국자연보존위원회 34명의 국내학자와 미국 스미소니언연구소(Smithsonian Institution) H. K. Buechner 박사를 대표로 5명의 국외학자가 공동으로 종합적인 학술조사를 수행하였다. 이는 DMZ 연구의 시작을 알렸으며, 이후 남북관계나 시대여건에 맞추어 간헐적으로 다양한 조사 및 연구들이 이어져오고 있다. 2015년부터 2018년까지 DMZ 철책주변 현장조사를 통해 확인된 식물현황은 964분류군이다. 군시설로 인해 식물서식환경이 제한적인 상황이지만 척박한 환경에 적응하고 있는 식물은 다양하다. DMZ와 맞닿아 있는 7개 지역에 대한 식물현황은 철원 638분류군, 연천 631분류군, 양구 525분류군 순으로 나타났다. 대부분 중동부 지역에 높은 식물종수가 나타났으며, 서부와 동부의 식물들이 고르게 나타나는 결과로 보인다. 큰잎쓴풀, 봉래꼬리풀 등 희귀식물도 있는 반면, 잠재적으로 생태계에 영향을 줄 수 있는 침입외래식물도 다수 포함되어 있어서, 지속적인 모니터링 및 관리가 필요하다. 그 중에서도 양구지역에 새롭게 발견된 Macleaya cordata (Willd.) R.Br.(양귀비과)는 독성이 포함된 식물이며, 인제에서 2014년에 발견된 미역취아재비는 DMZ일원에 제한적으로 분포하는 종이였으나 현재 연천에서 발견되는 등 확산에 대한 관리방안이 필요하다.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.6
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• pp.472-482
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• 2019

This paper describes the stabilization of underwater TAS winch system Deploy/Recover operation performance. TAS winch installed on the stern of submarine performs to deploy/recover sensor, towing cable and rope tail which is deployed from the stern and separated from submarine itself. Also TAS winch provides transmission path of power to the sensor and data transmitting/receiving path which data are acquired from underwater environment like sound, depth and temperature. At the step of TAS winch evaluation test, sporadic standstill and rotating speed oscillation phenomenon were occurred. Winch motor provides the available torque to deploy/recover TAS and root cause analysis to the winch motor was done to find exact reason to sporadic malfunction. When winch motor was disassembled, eccentricity of rotor, slip-ring and the other composition part for winch motor were found. These might cause magnetic field distortion. To make TAS winch system more stable and block magnetic field distortion, this paper suggests methods to enhance fixing status installed in winch motor. For reliable data acquisition for TAS winch operation, the deploy/recover function of the improved type of TAS winch was verified in LBTS making similar condition with sea status. At the end of stage, improved type of TAS winch was tested on some functions not only deploy/recover function, but sustainability of TAS operation on specific velocity, steering angle of submarine in the sea trial. Improved type of TAS winch was verified in accordance with design requirement. Also, validity of suggested methods were verified by the sea trial.

• Cross-Cultural Studies
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• v.40
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• pp.7-39
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• 2015

A kite in Japanese is the octopus. The reason is that when they saw the tail of the kite, they remembered the foot of octopus. And this kinds of associative action is called a mitate(見立て) in Japanese. Mitate is similar to metaphor, but these two concepts are somewhat different in causing laugh. Korean and Chinese comedic story's metaphor cause laugh by similarity of two things, but Japanese comedic story's mitate cause laugh by dissimilarity of two things. Chinese and Korean comedic stories focus on 90%'s similarity of two things, but Japanese comedic stories focus on 10%'s dissimilarity of two things. So, in this paper, I tried to consider the mitate of comedic stories of East Asia, and I found that there are the following three features. First, we can see the tendency of Chinese and Korean comedic stories's mitate concern on the human body's physical weakness. But, Japanese comedic stories subject to not the human body's physical weakness but the human's professional or identification temperament. Second, East Asian's comedic stories mitate which related character and word play came from the method of decomposition of Chinese characters, for that area's people have used Chinese characters for a long time. However, there are different cases in Japanese comedic story's Chinese characters mitate, where that characters mitate is combined with two different type's characters, for example, to associate one Chinese character and another Japanese characters, hiragana or katakana. Third, there are next type's mitate which came from misunderstanding of Chinese characters, it can be seen in Chinese and Korean comedic stories. Perhaps, this pattern related with Chinese three syllable's character pattern, which is a Chinese traditional word and character play.

• Korean Journal of Ichthyology
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• v.31 no.3
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• pp.131-140
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• 2019

This study is to observe species identification and early life history of Gnathopogon strigatus and to use it as a basis for taxonomic studies and conservation of species. For the experiments, the mature adults were collected at the Wang-suk Stream located in Namyang-ju city, Gyeong-gi Province and eggs were artificially fertilized by the wet method in the laboratory. The shape of the fertilized egg was globular, adhesive, opaque white in color and had no oil globules. The fertilized egg was 1.66~1.88 mm (average 1.76 mm, n=30) in diameter. The blastular stage occurred at 3 hours 05 minutes after fertilization and the gastrular stage was detected at 8 hours 30 minutes after fertilization. The embryo began to hatch about 54 hrs after fertilization under water temperature of $23{\pm}1^{\circ}C$ and the newly hatched larva (yolksac larva) were 4.1~4.7 mm (mean 4.4 mm, n=20) in total length (TL). The fourth day after hatching, the postlarva were 5.4~5.9 mm (mean 5.6 mm, n=20) in total length, their york sacs were completely absorbed and Start eating Artemia sp. Ten days after hatching, flexion larva were begins Notochord flexion were 7.5~8.6 mm (mean 8.1 mm, n=20) in total length. Sixteenth day after hatching, postflexion larva were complete Notochord flexion were 8.2~9.7 mm (mean 9.1 mm, n=20) in total length. At thirty-eight days after hatching, Juvenile were arrive integer all fin rays and similar to those of adults were 11.3~15.5 mm (mean 13.3 mm, n=20) in total length.

• Korean Journal of Ichthyology
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• v.33 no.3
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• pp.167-176
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• 2021

This study was carried out to clarify the egg, larvae and juveniles development of Abbottina springeri. For the experiments, the matured adults were collected at the Seowon-cheon, Dangjin-si, Chungcheongnam-do, in Korea. The amount of spawning of female A. springeri was about 1,225~2,100 (1,662±437, n=10). The fertilized eggs were circular in shape and 1.05~1.13 (1.08±0.02, n=30) mm in diameter. The hatching time was required 72 hours to 80 hours after fertilization under water temperature of 22℃. The newly hatched larvae were 2.10~2.23 (2.16±0.04, n=10) mm in total length and had egg yolk in the abdomen but the mouth was not opened. At 5 days after hatching, the preflexion larvae were 3.19~3.30 (3.24±0.03, n=10) mm in total length and the most of yolk-sac was absorbed. At the 15 days after hatching, the flexion larvae were 4.97~5.30 (5.13±0.12, n=10) mm in total length and the tip of the caudal fin was began to bend upward. At the 25 days after hatching, the postflexion larvae were 8.97~9.60 (9.44±0.16, n=10) mm in total length and the tip of the caudal fin was bent at 45°. At the 35 days after hatching, the juvenile were 12.0~13.5 (12.7±0.53, n=10) mm in total length and all fin-rays (iii7 dorsal fin, iii6 anal fin, i7 ventral fins) were reached a constant number of each part.