• The Journal of Korea Robotics Society
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• v.4 no.1
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• pp.43-48
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• 2009

Generally, underwater vehicle type of propeller shows low efficiency about 50%-55%. However, the efficiency of swimming mechanism of a fish is 60%-70%, more efficient about 20% than screw propellers. Recently, research of underwater vehicle type of fish increase due to its good efficiency and is regarded as a typical bio-mimical robot. In this research, a new algorithm and mechanism that show low energy consumption imitating swimming mechanism of fish proposed increasing speed and running time in field trial.

• The Journal of Advanced Prosthodontics
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• v.6 no.5
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• pp.423-426
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• 2014

This clinical report presents the clinical appearance and treatment approach in a case of excessive anterior teeth erosion resulted from swimming in a poorly-chlorinated swimming pool. Clinical findings revealed tooth sensitivity, severe enamel erosion resembling veneer preparations, and the presence of anterior open bite. A novel hybrid ceramic (Vita Enamic) was chosen for fabricating full-coverage crowns for this patient. After 6-months follow-up, the tooth sensitivity disappeared and the patient was satisfied with esthetic outcome. The hybrid ceramic restorations can be recommended with no complications.

• Development and Reproduction
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• v.10 no.1
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• pp.19-32
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• 2006

Genomic DNA isolated from two species of Korean freshwater crab(Eriocheir sinensis) and swimming crab(Portunus trituberculatus) was amplified several times by PCR reactions. The seven arbitrarily selected primers OPA-05, OPA-13, OPA-16, OPB-06, OPB-15, OPB-17 and OPD-10 were used to generate the identical, polymorphic, and specific fragments. 505 fragments were identified in the freshwater crab species, and 513 in the swimming crab from Buan: 81 specific fragments(16.0%) in the freshwater crab species and 100(19.5%) in the swimming crab. 165 identical fragments, with an average of 23.6 per primer, were observed in the freshwater crab species. 66 fragments, with an average of 9.4 per primer, were identified in the swimming crab species. The numbers of polymorphic fragments in the freshwater crab and swimming crab were 50 and 14, respectively. The oligonucleotides decamer primer OPB-17 generated identical DNA fragments, approximately 300 bp, in both the freshwater crab and swimming crab species. Compared separately, the average genetic difference was higher in the swimming crab than in the freshwater crab species. The average genetic difference was $0.726{\pm}0.004$ between the freshwater crab and swimming crab species. The dendrogram obtained by the seven primers indicates four genetic clusters: cluster 1(FRESHWATER 01), cluster 2(FRESHWATER 02, 03, 04, 05 and 06), cluster 3(FRESHWATER 07, 08, 09, 10 and 11), and cluster 4(SWIMMING 12, 13, 14, 15, 16, 17, 18, 19, 20, 21 and 22). The shortest genetic distance displaying significant molecular difference was between individuals SWIMMING no. 18 and SWIMMING no. 17 from swimming crab(0.096). Ultimately, individual no. 02 of the freshwater crab was most distantly related to freshwater crab no. 03(genetic distance = 0.770). As stated above, the potential of RAPD-PCR to identify diagnostic markers for the identification of two crab species has been demonstrated.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.43 no.4
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• pp.301-309
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• 2007

In order to develop the artificial bait of trap for swimming crabs, the attracting effect was analyzed in the duration time of attracting effect, preference and shape recognition to the bait in the water tank and field experiments. According to the result which investigated the mean entrapped number of swimming crabs into the trap for each bait(mackerel, sardine and anchovy) in water tank experiments, the mean entrapped number was found to be higher in the trap with mackerel(6.9 ind.; 23.0%) than in other traps with sardine(5.2 ind.; 17.3%) and anchovy(3.4 ind.; 11.3%). In addition, the mean entrapped ratios of swimming crabs into the traps for 3 kinds of baits were estimated to be over 80% all in 5 hours after soaked in the water tank. For preference of swimming crabs to 3 kinds of baits, the trap with mackerel(6.9 ind.; 23.0%) was evaluated to be higher than the traps with sardine(2.8 ind.; 9.3%) and anchovy(0.2 ind.; 0.7%). In the field experiments, the mean entrapped number of swimming crabs into the trap with mackerel and sardine were found to be similar as 120 and 118 ind., but the trap with anchovy was only 85 ind.. According to the result which investigated the shape regnition of swimming crabs to the bait used mackerel, divided into 8 pieces, 16 pieces and grinded mass in water tank experiments, the mean entrapped number of swimming crabs into the traps that includes the mackerel divided into several pieces was significantly decreased. Moreover, by the presence of skin of mackerel for bait, there was a great difference in the entrapped number of swimming crabs. Therefore, it was thought that the swimming crab was attracted to the bait and entrapped into the trap would indicate that not only the chemical stimuli such as the attactant, but also the visual stimuli such as the shape recognition to the bait might be closely related.

• Journal of Environmental Science International
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• v.4 no.4
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• pp.357-365
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• 1995

The use of chlorinated water in swimming pools produces elevated chloroform levels in the water and air of the pools which can cause chloroform body burden of swimming individuals. Present study confirmed the chloroform body burdens from a 40-min swimming and evaluated the decay of chloroform breath concentration after the cessation of a 60-min swimming. Air and water concentrations were measured in the pools. The water and air chloroform concentrations ranged from 18.1 to 25.3 ${mu}g/l$ and from 30.9 to 60.7 ${\mu}g/m3$ for the confirmation study, respectively. The breath level after 40-min swimming was about 64 to 266 folds higher than the corresponding background breath. The breath concentration after the 40-min swimming ranged from 10.5 to 21.3 ${\mu}g/m3$, while that prior to the corresponding swimming ranged from 0.07 to 0.19 ${\mu}g/m3$. In addition, the post-exposure breath level varied with the subjects who swam in the pool on the same visiting day. Breath concentration increased gradually during 60-min swimming, then decreased rapidly within 5 minutes after the cessation of exposure, after that, decreased slowly, and finally approached to a background breath level at 1-2 hr after exposure.

• Journal of Korea Entertainment Industry Association
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• v.13 no.4
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• pp.173-184
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• 2019

The data processing of this study is based on the word data search in social media through textom and the big data analysis is carried out and three areas (2019 Gwangju World Swimming Championships, 2019 Gwangju World Swimming Masters Competition, 2019 World Swimming Championships Problem) was consistently handled through data collection and refinement in the web environment. We applied the collected words to the program of Ucinet6, visualized them, and conducted a CONCOR analysis to grasp the similar relationship of words and to identify the cluster of common factors. As a result of the analysis, the clusters related to the 2019 Gwangju World Swimming Championships mainly consisted of four major areas of recognition and perception, mainly searching for operational aspects related to the swimming championship, and the community related to the 2019 Gwangju World Swimming Masters Competition Is mainly searched for the promotion of the Masters Competition and the aspect of the competition divided into two areas of major recognition and peripheral recognition. The cluster related to the problems of the 2019 Gwangju World Swimming Championships is divided into five areas, And they are mainly searching for the place, operation, institution, event, etc. of the problem of the swimming championship.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.47 no.4
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• pp.411-418
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• 2011

As a fish way is a structure for fish migrating well toward upper stream due to breaking river flow by a dam or dammed pool, the specific fish's swimming ability is one of the main factors in making a plan and managing it. In addition, it also needs to understand the current field in fish road to evaluate its performance. This study is aimed to analyze the swimming patterns with current velocity changes using a Particle Imaging Velocimetry (PIV) in order to understand the swimming ability of silver fish (Plecoglossus altivelis) that is one of the fishes migrating through the fish way of Nakdong River, and to analyze the 2 dimensional current field near to silver fish at swimming momentum. The results showed that average values of tail beat frequencies for continuous swimming with current velocity were 2.8 Hz at 0.3 m/s, 3.2 Hz at 0.4 m/s, 3.8 Hz at 0.5 m/s, respectively. The wake would be produced by direction turning of fish's tail fin and its magnitude would be verified by the difference of pressure. The pressure turbulent flow produced by its tail beat would be made in both sides, and then, the magnitude of wake should be the source of moving direction. The swimming momentum will help to support the primary factor in making a suitable design for specific fish species migrating toward the district river.

• Journal of the Korea Safety Management & Science
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• v.20 no.2
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• pp.9-20
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• 2018

This study is empirically intended to look into the effects of HVAC management on condensation cause and prevention in indoor swimming pools. The findings are summarized as follows. First, the experience of condensation in indoor swimming pools showed that 132 out of 142 people in total experienced the condensation in indoor swimming pools, which they had a high experience rate of 92.3%. For the location of condensation, the wall joints were 46.8% and the windows were 34.5%, which a total of 72.3% occurred in the wall joints and windows. Second, the effect of construction design, HVAC management and building construction on the cause of condensation in indoor swimming pools showed that building construction had an effect on the cause and location of condensation depending on the seasonal time, partially adopting hypothesis 1. Third, the effect of condensation-causing factors on condensation-preventing factors in indoor swimming pools showed that condensation had a close relationship with air and temperature conditions depending on the time and location of condensation, adopting hypothesis 2. As for the above-stated findings, the HVAC management in indoor swimming pools is an important concern factor that continues to cause condensation despite the development of advanced construction materials. Especially, building construction is a main factor that has a direct effect on condensation in the HVAC management of facilities. This implies that the window management is important in maintaining the wall joints - which can suppress the selective use and defect occurrence of construction materials - or confined spaces for a long time.

• Journal of the Korean Society of Costume
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• v.53 no.4
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• pp.49-69
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• 2003

The purpose of the study is to develop the competitive swimming suit design with Korean traditional images. which excels in dimension of functionality, aesthetics, and symbolism. To accomplish this study, first. a theoretical examination about Korean image was added, on the basis of the practical research about professional swimmers' preferences as well as the theoretical research about the history of swimming suits and the qualifications of competitive swimming suits in the prior study. Next, practical designing was performed to achieve the creative designs according to Lamb & Kallal's design process. and the superiority of the newly designed swimming suits was evaluated by using Grant's alpha-beta model. The results of this study can be summarized as follows : First. in the problem apprehension stage. the need for swimming suit designs with Korean traditional images for professional swimmers was acknowledged, and three major criteria. which are functionality, aesthetics. and symbolism has been verified. Second. in the preliminary brainstorming stage, considerable amounts of data for the design concept considering the criteria above have been gathered. The athletic one-piece for women and the brief for men in style and nylon/lycra in fabric were used in the aspect of functionality. And the S Korean traditional colors in color and Tae-guk motive and others in pattern were selected to apply Korean traditional images in the aspects of aesthetics and symbolism. Finally, the 13 series of creative designs with 4 themes( l17pieces in total) have been suggested. Third, in the design improvement stage. after the preference to each design was surveyed, reformation of the designs was arranged on the basis of the results. Fourth, in the prototyping stage. the 17 actual prototypes, including 13 pieces for women and 4 pieces for men were produced. Fifth. in the evaluation stage. the evaluation procedure using Grant's alpha-beta model was performed. As a result, the newly designed swimming suits were rated above other existing ones in all three aspects of functionality, aesthetics, and symbolism.

• Preventive Nutrition and Food Science
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• v.10 no.2
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• pp.151-155
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• 2005

This study was intended to investigate the effects of regular swimming exercise and vitamin C supplementation on the antioxidant system following exercise stress. For the swimming exercise experiment, a swimming adaptation exercise of 1 week was given to a group of 6-week-old mice. Following this, a swimming exercise for 8 weeks was conducted. The experimental group was divided into 3: a control group (C), a swimming exercise trained group (T), and a group of swimming + vitamin C supplementation (TC: vitamin supplementation: 1.3 mg/l00 g diet). After the swimming exercise, these group were further divided into those that had received the exercise stress for 2 hours and those that had not experienced exercise stress group. Then, the activities of the superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and malondialdehyde (MDA) concentrations were measured. There was a lower weight increase in the T and TC groups than in the C group, and there was no significant difference between T and TC group. When exercise stress was not experienced, the activity of SOD was significantly increased in the TC group than in the T group, but there was no significant difference between C and T groups. The groups that had experienced a 2-hour exercise stress showed the SOD activity levels according to the following order, C < T < TC, with a significant difference between the three groups (p<0.05). There was no difference in MDA concentration amongst the experimental groups in non-exercise stress group. As well, there was no differences in MDA concentration between the C group and T group in the 2 hour exercise stress group. However, the TC group showed a MDA concentration level significantly lower than that of the T group. A significant increase in MDA concentration was observed in C group, when exercise stress was provided with no significant difference in the T and TC groups. As a result, regular exercise and vitamin C supplementation can be considered important in controlling the formation of lipid peroxides in exercise stress.