• Fisheries and Aquatic Sciences
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• v.5 no.3
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• pp.206-211
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• 2002

The aim of this study was to obtain the basic data on the fish school behavior change to approaching vessel and fish species identification by means of their swimming speed. The surveys were carried out for the juvenile southern blue fin tuna and other fish schools off Esperance, western Australia from January to March 1999. We observed changes of fish school behavior in response to the approaching vessel using 360-degree scanning sonar. The results showed that, a horizontal direction index used to quantify a change of fish school behavior did not identify dependence of a radial distance and a swimming speed. A Mann­Whitney test conducted using the horizontal swimming speed of both species identified by sonar specialists, did not reveal a significant difference.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.46 no.3
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• pp.273-281
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• 2013

The movement patterns of fish aggregations swimming freely near artificial reefs on August 24, 2006, at Suyeong Man, Busan, Korea, were acoustically investigated and analyzed. Acoustic surveys were conducted using a 70kHz split-beam echo sounder, 330 kHz side-scan sonar and a 310 kHz imaging sonar. Algorithms for tracking the movement of fish aggregations swimming in response to artificial reefs were developed. The travel direction and the swimming speed for two aggregations of fish were estimated from the trajectory orientations of echo responses recorded by the imaging sonar.The first group was floating just above the reef structure, while remaining in the midwater column, and the second group was swimming through and around artificial reefs near the seabed. The mean swimming speed was estimated to be 0.40 m/s for the midwater fish aggregation and 0.17 m/s for the bottom aggregation close to artificial reefs. These results suggest that the swimming behavior of fish aggregations passing close to artificial reefs near the seabed displayed a slower moving pattern than fish floating just above the reef structure in the midwater column.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.31 no.1
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• pp.74-83
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• 1995

To estimate the parameters of a mathematical model of fishes' swimming behavior, the behavior in a experimental water tank was observed and analyzed using the video monitoring system. The tank was equipped with vertical circulation system, and measured $3,500L\;{\times}\;1,500B\;{\times}\;1,000H\;mm$ at flow channel and $1,200L\;{\times}\;900B\;{\times}\;500H\;mm$ at observational part. Rainbow trout, salmo gairdnerii were used as experimental fishes. Their swimming behavior in the tank was observed by the monitoring system, and the positions of every individual were checked at 0.5 second intervals by the image processing of recorded pictures for 5 minutes. The mean swimming speed calculated from the time series data of positions of every individual ranged from 2.5BL cm/sec to 2.9BL cm/sec at the stagnated flow. The mean swimming speed of 10 individuals in a school increased according to the flow speed. The mean swimming depth ranged from 17 cm to 38 cm even though it changed irregularly at the stagnated flow and gradually became stable according to the increase of flow speed. In the present study, the mean distance of individuals from wall of the tank varied from 17.6cm to 21.4cm. The mean distance between the nearest individual varied from 0.4BL cm to 0.7BL cm when 10 individuals in a school were observed. The mean dimension of fish schools became enlarged in all directions according to increase in the number of individuals, and as flow speed increased the horizontal dimension of fish schools expanded while their vertical dimension decreased.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.46 no.2
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• pp.148-156
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• 2010

This study was conducted to collect the information on the behavioral characteristics and the habitat environment of mandarin fish (Siniperca schezeri) and catfish (Parasilurus asitus) with acoustic telemetry method in Chungju Lake, Korea. Mandarin fish tended to stay within 1km from the release points in downstream, and had a strong diurnal behavior. They approached to the lakefront at night. They also preferred to stay at deep water off the lakefront. The average swimming speed was faster at night (0.4BL/s) than during a day (0.2BL/s). They swam the shallow water area at night. Catfish frequently moved between upstream and downstream. Catfish tended to act during a day. The average swimming speed was faster during a day (0.3BL/s) than at night (0.2 BL/s). The average swimming depth was 14.3m, and they tended to float about 4m during a day.

• Fisheries and Aquatic Sciences
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• v.10 no.4
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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.

• Journal of Life Science
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• v.19 no.10
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• pp.1489-1494
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• 2009

This study was designed to investigate the effects of swimming and minocycline on motor function recovery and Bcl-2 expression after spinal cord injury (SCI) in rats. After operation, neurological motor behavior test (BBB scale) on days 1, 4, 7, 10, and 14 were tested. Western blot and immunohistochemical assessment (Bcl-2) were performed on day 14. BBB scale started to show a statistically significant difference on day 7 (p<0.05). On day 14, it showed the most significant (p<0.05) difference. Expression of Bcl-2 increased in all the experimental groups. In particular, the highest expression of Bcl-2 appeared in the swimming and minocycline groups. Based on these results, minocycline and swimming were the most effective factors in the motor behavior function and immunohistochemical assessment of SCI rats.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.55 no.2
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• pp.129-137
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• 2019

This study was conducted to investigate the effects of underwater noise caused by pile driving during marine construction on fish. In this study, the three gray rockfish were released about 1 km away from the construction site of wind power generation on July 18, 2018 and traced using two acoustic telemetry techniques. The behavior of the fish was analyzed by calculating the moving distance, swimming speed and direction of the gray rockfish. In the results of the acoustic tracking using the ship, the rockfish moved about 2.11 km for about two hours at a speed of $0.28{\pm}0.14m/s$ (0.94 TL/s). The bottom depth of the trajectory of the rockfish was $1.0{\pm}0.6m$ on average. There was a significant directionality in swimming direction of the gray rockfish, and there was no significant correlation between the swimming direction and tidal current direction. Moving distance during 5 minutes (5MD) during pile driving and finishing operations between rock surface and bedrock were 0.94-0.96 times (76.0-77.0 m) and 1.81-2.73 times (146.0-219.5 m), respectively, compared with no pile driving. This study is expected to be used as a basic data of fish behavior research on underwater noise.

• Fisheries and Aquatic Sciences
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• v.5 no.3
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• pp.212-218
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• 2002

The response behavior of a fish school to an approaching vessel was observed using scanning sonar. The evaluation using six parameters, which signify characteristics of school shape and behavior by sonar image processing, was proposed. Ten fish schools were analyzed and among them, three fish schools were identified for their changing shape, swimming direction, and swimming speed. Moreover, by tracing fish schools on stack of sonar images, these fish schools were seen to exhibit an apparent change of school shape and behavior. Therefore, the evaluation method of fish school behavior using six characteristic parameters indicating fish school shape and behavior by sonar image processing is useful.

• Journal of the Korean Applied Science and Technology
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• v.38 no.3
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• pp.735-749
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• 2021

There is true that the evaluation of non-face-to-face swimming classes currently offered by universities due to the COVID-19 outbreak is generally negative. For this reason, the quality of non-face-to-face swimming classes at universities is bound to depend on the expertise of the instructor. However, whether or not of students who lack of practices of swimming could experience exercise flow and could continuously last the swimming exercise after semester or even graduation is difficult to confirm. This is considered to be a significant threat in the future not only for swimming, but also for all liberal arts and lifestyle sports. This study aimed at 281 non-athletic college students with experience of taking both swimming classes, and the need for a study on the structural relationship between exercise flow and participation intention by university swimming class leaders' expertise in non-sports majoring college students. And the results were empirically analyzed. The research results derived in this process are summarized as follows. First, the effect of swimming class leader's expertise (personality, lecture skills, student management, practical skills, basic knowledge) perceived by non-athletic college students on exercise flow (cognitive flow, behavior flow) affects cognitive flow. As a factor influencing, it was found that lecture skills had a statistically positive (+) effect, and as factors influencing behavioral commitment, the positive (+) effect was statistically significant in personality, lecture skills, student management, and basic knowledge. Second, as for the effect of exercise commitment (cognitive commitment, behavior commitment) perceived by non-athletic college students on continuous participation intention, the behavioral commitment factor was found to have a statistically positive (+) effect.

• Fisheries and Aquatic Sciences
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• v.9 no.4
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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.