• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.34 no.3
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• pp.241-258
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• 1998

The experimental demersal trawl surveys to provide the essential information for the assessment, management and utilization of commercially important fish stocks in the southern waters of Korea were carried out during five research cruises between October 1996 and October 1997 by the training ship “KAYA” of Pukyong National University. The biological sampling was conducted by using the trawl net with a cover net of 36 mm in mesh size at 64 planned trawl stations during daylight to identify the biological characteristics of fish. Each catch was standardized into catch per unit of time and the catches at each trawl station were sorted, weighed and counted by species. The changes in catches of each fish species and the shifts in dominant species by seasions and sampling regions in the research area were analyzed, and the abundance of fish was estimated from the relationship between the trawl catches and the volume of the water column sampled by demersal trawls. The results obtained can be summarized as follows : 1. During the 64 demersal trawls conducted in the southern waters of Korea, 129 species including 112 species of fishes, 8 species of Cephalopoda and 7 species of Crustacea, were identified Also, during the 1996 and 1997 trawl surveys in the reseach area, a large number of commercially important species with small differences in proportion was found. me proportion of Japanese horse mackerel which comprised 19.8% of the total catch by weight was highest, followed by chub mackerel(15.0%), swordtip squid(9.0%), redwing searobin(6.2%), konoshiro gizzard shad(6.1%), Japanese flying squid(5.8%), silver pomfet(5.1%), blackmouth goosefish(5.1%), etc. Swordtip squid, Japanese flying squid, blackmouth goosefish and blackthroat seaperch were among the dominant species in all seasons with a relatively high and stab1e proportion(3.6~9.0%), and were widely distributed in the entire southern water of Korea. 2. The catch rates by cover net varied at 0.7~91.9% by weight of the total trawl catch by codend and cover net at 64 planned trawl stations and the mean catch rate was 44.4%. Species comprising a major portion of the catches by cover net mainly were swordtip squid, konoshiro gizzard shad, the juveniles of Japanese horse mackerel, blackthroat seaperch and chub mackerel, etc. 3. The distribution density of fish in terms of biomass per unit volume which derived from the catch data by 63 bottom trawl hauls in the southern waters of Korea ranged from 17.9 $\times$ 10-6 to 1,440.9 $\times$ 10-6kg/m3 with the mean value of 153.8 $\times$ 10-6 kg/m3. These fish densities varied between seasons, location of sampling stations and sea conditions. From these results, it is worth noting that the catch composition of multispecies and the increased occurrence of small fish in the southern waters of Korea may also result in new problems in determining the total allowable catch(TAC) levels for economically important species.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.18 no.3
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• pp.142-161
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• 2013

In order to enhance scientific interest and a sense of affinity about ocean, the programs of the oceanic camp 'oceanic summer school' were developed and applied to $4^{th}$ and $9^{th}$-grade elementary and middle school students for 9 years from 2004 to 2012. It was composed of oceanic training for snorkeling, a tour to oceanic institutes and museums near the camp academy place, experimental learning in oceanic-related field, field trips for ocean and earth sciences, and lectures on various subjects of ocean. We developed and implemented 9-kinds of inquiry surveys to evaluate changes in cognitive and affective characteristics, and ocean literacy of students participated at the present oceanic summer camp. Based on the statistical analysis, affective characteristics such as interest, inquisitiveness, passion, and so on, were enhanced. Analysis of ocean literacy revealed that cognitive characteristics of the students were increased by 40%. We presented parents' responses on the programs of oceanic summer school. Some students with less initial interest of ocean have positively changed to make up their minds to be a oceanographer in several years later. In light of this, the summer school can be evaluated to be successfully functioned as a long-term support system for potentially young-talented students in the field of ocean science. This study addresses that long-term implementation of the summer oceanic camp may trigger students with potential talent toward in-depth science in the near future even though it could not bring positive effect immediately. This addresses the necessity of policy supports in order that various programs like the scientific camp should be more constructively developed and executed for next-generation manpower in oceanographic fields.

• Korean Journal of Remote Sensing
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• v.38 no.6_1
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• pp.1463-1478
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• 2022

Maritime transport accounts for 99.7% of the exports and imports of the Republic of Korea; therefore, developing a vessel monitoring system for efficient operation is of significant interest. Several studies have focused on tracking and monitoring vessel movements based on automatic identification system (AIS) data; however, ships without AIS have limited monitoring and tracking ability. High-resolution optical satellite images can provide the missing layer of information in AIS-based monitoring systems because they can identify non-AIS vessels and small ships over a wide range. Therefore, it is necessary to investigate vessel monitoring and small vessel classification systems using high-resolution optical satellite images. This study examined the possibility of developing ship monitoring systems using Compact Advanced Satellite 500-1 (CAS500-1) satellite images by first training a deep learning model using satellite image data and then performing detection in other images. To determine the effectiveness of the proposed method, the learning data was acquired from ships in the Yellow Sea and its major ports, and the detection model was established using the You Only Look Once (YOLO) algorithm. The ship detection performance was evaluated for a domestic and an international port. The results obtained using the detection model in ships in the anchorage and berth areas were compared with the ship classification information obtained using AIS, and an accuracy of 85.5% and 70% was achieved using domestic and international classification models, respectively. The results indicate that high-resolution satellite images can be used in mooring ships for vessel monitoring. The developed approach can potentially be used in vessel tracking and monitoring systems at major ports around the world if the accuracy of the detection model is improved through continuous learning data construction.

• Journal of the Korean Society of Marine Environment & Safety
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• v.28 no.1
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• pp.19-29
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• 2022

The result of a questionnaire survey conducted on fishermen using coastal fish traps shows that fall accidents during trap dropping and pulling constitute the highest proportion of accidents at 42.1 %, whereas slipping accidents on the deck or stricture accidents to the body due to the trap winding device constitute 21.1 % each. In addition, 53.2 % of all surveyed subjects responded that trap pulling is the most dangerous task, followed by fish sorting 33.8 %, and trap dropping 9.1 %. As for the main items requested by fishermen for improving the trap winding device, 36.8 % indicated a method to easily lift the trap from the water to the work deck, and 31.6 % indicated a method to overcome the rope tension and prevent slip when pulling the trap to reduce the accidents. The small trap fishing vessel winding device proposed herein can increase the winding force by strengthening the rope contact area and friction coefficient via an appropriate contact angle between the driving roller of the winding device and the rope. When the contact angles between the driving roller and the rope are 1°, 5°, 9°, 14° and 19°, the rope tension showed a difference according to each contact angle. When the contact angle is 9°, the rope tension is the highest at 392.62 kgf. Based on these experimental results, a prototype winding device is manufactured, and 25 traps are installed on a rope with a total length of 100 m at 4 m intervals in the sea, and then the rope tension is measured during trap pulling. As a result, the rope tension increases rapidly at the initial stage of trap pulling and shows the highest value of 31.89 kgf, which subsequently decreases significantly. Therefore, it is appropriate to design the winding force of a small trap fishing vessel winding device based on the maximum tension value of the rope specified at the beginning of the trap pulling operation.

• Asia-pacific Journal of Multimedia Services Convergent with Art, Humanities, and Sociology
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• v.8 no.12
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• pp.425-435
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• 2018

The purpose of this study is to investigate the cultural value as well as business value of Juk-Bang-Ryeum(fishing instrument made by bamboo weir) by the investigation of remains in Gyeongnam Sacheon area and reviewing various historical literatures. The research will contribute to make back data necessary for the registration of World Heritage(UNESCO) and Globally Important Agricultural Heritage Systems(FAO). Fisheries, along with agriculture, have been great significance in human history. In particular, the Fisheries has been considered very important industry due to the geopolitical characteristics of our country surrounded by the sea. We can imagine may types of fishing practices and instruments at the agricultural age. Nonetheless, there are a few fishery heritages such as collecting and hunting tools that remains today. Fortunately, there are many Juk-Bang-Ryeum which is actually operate now from the past 500 years ago at the The Sacheon and Namhae areas. We could found some literature records about it in the historical ancient literatures. We could also infer that Juk-Bang-Ryeum was an important fishery resource of the country for a long time. It was built on the basis of scientific principles to capture fishes using the rapid tide of the natural geological straits, and it prove the wisdom of our ancestors. We also could found some unique cultural heritages that was important to the local community. Naturally, it has been managed as an important asset for the residents. In addition to such historical and humanistic values, it also has business and educational value. It can be useful to understand scientific fishery principles as well as fishery experience field. It has business value as an important tourism resource in the region in connection with historical relics and geological environment resources. In conclusion, it is a valuable asset to be handed down as a valuable cultural heritage.