• Fisheries and Aquatic Sciences
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• 제9권4호
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• pp.167-174
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• 2006

Two typical responses have been documented for flatfish when they encounter the ground gear of bottom trawls: herding response and falling back response. These two responses were analyzed from video recordings of fish and were characterized by time sequences for four parameters: swimming speed, angular velocity, acceleration, and distance between the fish and the ground gear. When flatfish displayed the falling-back response, absolute values of the three swimming parameters and their deviations were significantly higher than those during the herding response. However, the swimming parameters were not dependent on the distance between the flatfish and the ground gear, regardless of which response occurred. The dominant periods for most of the movement parameters ranged from 2.0 to 3.7 s, except that no periodicity was observed for swimming speed or angular velocity during the falling-back response. However, variations in the four parameters during the falling -back response revealed greater irregularity in periodicity and higher amplitudes. This complex behavior is best described as a chaos phenomenon' and is discussed as the building block for a model predicting the responses of flatfish to ground gear as part of the general understanding of the fish capture process.

• 한국컴퓨터정보학회논문지
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• 제21권12호
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• pp.43-49
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• 2016

This paper presents the design and implementation of virtual aquarium by generating 3D models of fishes that are colored by viewers in an aim to create interaction among viewers and aquarium. The virtual aquarium system is composed of multiple texture extraction modules, a single interface module and a single display module. The texture extraction module recognize the QR code on the canvas to get information of the predefined mapping table and then extract the texture data for the corresponding 3D model. The scanned image is segmented and warp transformed onto the texture image by using the mapping information. The extracted texture is transferred to the interface module to save on the server computer and the interface module sends the fish code and texture information to the display module. The display module generates a fish on the virtual aquarium by using predefined 3D model with the transmitted texture. The fishes on the virtual aquarium have three different swimming methods: self-swimming, autonomous swimming, and leader-following swimming. The three different swimming methods are discussed in this paper. The future study will be the implementation of virtual aquarium based on storytelling to further increase interactions with the viewer.

• 동의생리병리학회지
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• 제23권6호
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• pp.1399-1403
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• 2009

The aim of the present study was to evaluate the possibility of protective effectness of swimming exercise and Gastrodia elata blume oral administration against beta-cell damage in streptozotocin (STZ)-induced diabetes in rats. The animals were divided into five groups: the normal group(n=10), the STZ-induced diabetes group(n=10), the STZ-induced diabetes and moderate-intensity exercise group(n=10), the STZ-induced diabetes Gastrodia elata blume(300 mg/kg) oral administration group(n=10), the STZ-induced diabetes and moderate-intensity exercise and Gastrodia elata blume(300 mg/kg) oral administration group(n=10). Animals in the exercise groups were made to swim moderate swimming exercise protocols once a day for 4 consecutive weeks. Serum glucose concentration and insulin level, superoxide dismutase (SOD) and catalase (CAT) were measured in serum. Swimming exercise and Gastrodia elata blume extract administration has shown anti-diabetic effect probably through decreasing serum glucose and insulin level and increasing antioxidant enzyme activity.

• Journal of Ginseng Research
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• 제20권2호
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• pp.139-148
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• 1996

This study was designed to examine the effects of red ginseng total saponin and extract on spatial working memory in mice using Morris water maze. Two kinds of red ginseng saponin (No. 1 and No. 2) and three kinds of red ginseng extract (No. 1, No. 2 and No. 3) to have different PD/ PT ratio (No. 1=1.24, No.2=1.47 No.3=2.41) were prepared by mixing the different parts of red ginseng In different ratio. In acute administration of total saponin No. 1 or No. 2, escape time to reach to a hidden platform In a fixed location for training trials was significantly decreased as compared with control group and swimming time in the quadrant that had contained the platform was also significantly increased as compared with control group. In acute treatment of extract No. 1 or 1 No. 2, swimming time in the platformless quadrant was increased dose dependently as compared with control group, especially at dose of 200 mg/kg,bw swimming time was significantly Increased. Oral treatment of extract No. 1 (100 mg/kg, bw) for 7 days produced an increase of swimming time In the platformless quadrant but a decrease of swimming time in No.3-treated group (100 mg/kg, bw). These results show that red ginseng may improve spatial discrimination learning and spatial working memory of mice

• 설비공학논문집
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• 제15권8호
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• pp.683-689
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• 2003

The thermal comfort of an indoor swimming pool is different from that of general indoor space because of the characteristics of large space and the wear conditions of swimmers. Dew condensation by humid air not only makes mold on the floor, wall and roof but also decreases the durability of buildings by penetrating into their structures. In this study, the characteristics of the flow field, the temperature field and the humidity distribution in an indoor swimming pool have been examined by the numerical method to estimate the level of thermal comfort and the generation rate of dew condensation. The results showed that the dew condensation regions were spread widely at the eastern parts of the swimming pool due to the insufficient air flow rate with low velocity and temperature. To prevent the generation of dew condensation in a region, a sufficient warm air flow rate should be supplied to make an air mixing. The values of PMV at horizontal plane of 1.5 m height have the range of -1.0∼1.2, which means the suitable level for swimmers.

• 수산해양기술연구
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• 제58권2호
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• pp.121-129
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• 2022

Density and sound speed contrasts (g and h, respectively), and swimming angle were measured for sandfish (Arctoscopus japonicus) without swimbladder. The density contrast was measured by the volume displacement method while the sound speed contrast was measured by the acoustic measurements of travel time (time-of-flight method). The swimming angle was measured by dividing it into daytime, nighttime, daytime feeding and nighttime feeding. The g was 1.001 to 1.067 with an average (± standard deviation) of 1.032 (± 0.017), and the h was 1.007 to 1.022 with an average (± standard deviation) of 1.015 (± 0.003). The swimming angles (mean ± standard deviation) were 16.8 ± 10.3° during the daytime, 1.9 ± 12.3° during the nighttime, 30.2 ± 12.6° in the daytime feeding and 35.0 ± 13.2° in the nighttime feeding. These results will provide important parameters input to calculate theoretical scattering models for estimating the acoustic target strength of sandfish.

• 한국안광학회지
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• 제18권4호
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• pp.357-363
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• 2013

목적: 실내수영장에서 도수 수경 착용에 따른 주관적 만족도 평가와 실내 검사실 및 수중에서의 시력을 비교하고자 한다. 방법: 실험에 참여한 대상자는 평균나이가 $22{\pm}1.54$세인 15명의 대학생이었으며, 오른쪽 눈과 왼쪽 눈의 평균 굴절이상은 각각 RE: S-1.67 D/C-0.40 D, LE: S-1.70D/C-0.37 D이었다. 모든 참여자는 기초적인 안과검사를 마쳤으며, 굴절이상을 교정하기 위한 콘택트렌즈 착용이 가능하고 수영이 가능한 자로 한정하였다. 모든 피실험자의 굴절이상은 콘택트렌즈를 이용하여, 정시상태로 교정을 하였다. 난시가 인위적으로 유발된 원주도수 수경(C+1.50 D, Ax $90^{\circ}$)을 착용하였을 때와 도수가 없는 수경을 착용하였을 때 시력, 안정피로, 그리고 수영장 주위를 걸을 때의 균형감각에 대한 주관적인 만족도 평가를 설문지를 이용하여 실시하였다. 시력 평가는 처방 S+3.00 D ~ S-3.00 D까지 0.50 D단위로 준비된 서로 다른 도수의 수경을 무작위의 순서로 착용한 상태에서 수영장내의 수중과 실내의 검사실에서 ETDRS 시표를 사용하여 측정하였다. 결과: 난시가 인위적으로 유발된 상태에서는 시력, 안정피로, 균형감각에 대한 3가지 만족도가 모두 유의하게 저하되는 것으로 나타났다. 서로 다른 도수의 수경을 착용하였을 때 시력은 유의하게 영향을 받는 것으로 나타났으나(p<0.05), 실내 검사실과 수중에서 측정된 시력의 차이는 없었다(p=0.173). 일부 도수 수경(+3.00, +1.00, +0.50, 0, -1.00, -2.00 D)에서는 실내 검사실에서 측정된 시력이 수중에서 측정된 시력보다 향상된 것으로 나타났다. 결론: 수중에서 수경을 착용하는 것은 시력을 저하시킬 수 있지만 저하되는 시력의 정도는 스넬렌 시력기준 1라인 이내 차이로써 실제 임상에서는 거의 영향이 없을 정도로 적은 수준이었다. 하지만 난시의 미교정은 시각적 만족도에 영향을 미치는 것으로 나타났으므로, 수영장의 미끄러운 환경을 고려하였을 때 안전사고의 위험이 내재한다고 할 수 있다. 따라서 도수 수경의 도수의 정확성과 더불어 난시의 교정이 필요하다고 할 수 있다.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2003년도 ICCAS
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• pp.1580-1586
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• 2003

This paper presents the design and the analysis of a "fish-like underwater robot". In order to develop swimming robot like a real fish, extensive hydrodynamic analysis were made followed by the study of biology of the fishes especially its maneuverability and propel styles. Swimming mode is achieved by mimicking fish-swimming of carangiform. This is the swimming mode of the fast motion using its tail and peduncle for propulsion. In order to generate configurations of vortices that gives efficient propulsion yawing and surging with a caudal fin has applied and in order to submerge and maintain the body balance pitching and heaving motion with a pair of pectoral fin is used. We have derived the equation of motion of PoTuna by two methods. In first method, we use the equation of motion of underwater vehicle with the potential flow theory for the power of propulsion. In second method, we apply the method of the equation of motion of UVM(Underwater Vehicle-Manipulator). Then, we compare these results.

• Fisheries and Aquatic Sciences
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• 제10권4호
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• pp.220-225
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• 2007

The movements of skipjack schools during purse seine operations were observed by scanning sonar in the Southwest Pacific Ocean in April 2004. Swimming speed and directional changes were analyzed in relation to heading of the purse seine during shooting, speed of the purse seiner and distance to the net. Escaped schools turned clockwise (relative to the heading of the purse seiner during shooting) significantly more frequently than captured schools, who primarily turned counter-clockwise. The swimming speed of a fish school, whether it was caught or escaped, was somewhat related to the ship's speed, but swimming speed did not differ between captured and escaped schools. The behavior of skipjack schools during purse seining consists of very complex movements with changes in swimming speed and direction in relation to the nets or purse seiner. Therefore, these responses of skipjack schools to purse seining can be useful for modeling the capture process of purse seining in relation to fishing conditions.

• 한국응급구조학회지
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• 제5권1호
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• pp.73-88
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• 2001

Post these safety tips in any swimming area for all swimmers to read. 1. Always swim with companions. Swim only in area well supervised by lifeguards. 2. Never drink alcohol or use drugs when you're swimming or boating. 3. Always check the water depth. Walk in from shore or ease in from the dock or the edge of the pool. 4. Know the limits of your own swimming abilities. If you're a good swimmer, don't tempt nonswimmers or beginner swimmers to try to keep up with you. 5. Keep any eye on younger swimmers at all times. 6. Learn the proper way to dive in the water safely. Follow guidelines for safe diving. 7. Follow the lifeguards instructions and respect their judgment. Never fake an Emergency. Obey all swimming rules.