Sensory evaluation of shucking pressure, pressure holding time, seeding method, difference in full shucking rate in the aquaculture area and shucking oyster was performed using an ultra-high pressure oyster shucking machine. The reaching time for each target pressure is 2.2-2.4 MPa/sec in the range of 180 MPa to 240 MPa. had a rate of pressure rise. There was a difference of 0.5-1.7℃ in the range of 24-27℃ in the seawater temperature before and after the pressure treatment inside the pressure vessel, but there was no specific increase or decrease in seawater temperature. When only the shucking pressure is increased without the pressure holding time, the critical shucking pressure at which the oyster shell is opened and the flesh is peeled in the range of 200 to 220 MPa. When the critical shucking pressure is reached, the oyster sample in the closed vessel is expected to be shucked by about 40%. If there is no pressure holding time when judged only by full shucking, an increase in pressure of about 1.5 MPa is required to further shuck 3% of the oyster population. The oyster samples cultivated in the south coast of Korea were subject to full shucking under the conditions of 220 MPa shucking pressure and two minutes (120 seconds) of pressure holding time, and the difference in the pressure of the oysters according to the oyster seeding method and the farming area was minute. Finally, the condition of 220 MPa of shucking pressure and three minutes of pressure holding time was the best at 1.52 when the result of the sensory evaluation performed manually was set to 1.0. Next was 1.4 under the conditions of 220 MPa of shucking pressure and one minute of pressure holding time (60 seconds), and 1.3 under the condition of 220 MPa and two minutes of pressure holding time (120 seconds). Therefore, it is considered that the most desirable shucking conditions, considering the efficiency and sensory evaluation results, are the conditions of 220 MPa shucking pressure and two to three minutes of pressure holding time.

In this study, an automatic system for improving the working environment and increasing production efficiency of a laver aquaculture industry in Korea was developed by combining a hydraulic control system and a load cell in a current landing work of the laver. The improved gathering laver system allowed the automatic gathering process of the laver in the sea with the hydraulic control system connected to a cutting machine of the laver on the operating ship, which has been used for gathering the laver semi-automatically in a form of the traditional farming method. The transporting process of the laver from an operating ship to the land was improved as follows. A frame installed on the operating ship and the bag nets were designed and made to hold about 1,000 kg of the laver inside. The bag nets contain the laver on the improved operating ship were tied in knots and hooked on a crane using a load cell. The weight is measured immediately by lifting the bag nets through the load cell system. Weight information is communicated to the fishermen and successful bidders through the application. The advantages of the improved system can help fishermen to fish by improving their working environment and increasing production efficiency. The field survey to improve the landing operation of the laver aquaculture was conducted in Gangjin, Goheung, Shinan, Wando, Jindo, and Haenam in South Jeonnam Province. A total of 10 sites including Gunsan in Jeonbuk Province, Daebu Island in Ansan City, Jebu Island in Hwaseong City in Gyeonggi Province, and Seocheon in Chungnam Province were searched to collect data. Prototypes of the system were tested at the auction house of laver located in Goheung, where laver collection using hydraulic control and landing using road cell could be improved.

본 연구에서는 장어 통발어선 자동화 조업장치 개발의 첫 단계로서 통발을 모릿줄에 기계적으로 연결, 분리할 수 있는 장치인 집게식 통발연결장치 및 통발자동분리장치를 개발하여 해상성능실험을 실시하였다. 본 연구에서 얻어진 결과를 요약하면 다음과 같다. 1. 집게식 통발연결장치가 무른 꼬임 트와인 고다리 및 된 꼬임 트와인 고다리에 각각 연결되었을 때, 그 사이의 최대 인장하중은 각각 1379 N및 1,603 N 이었다. 2. 집게식 통발연결장치에 대한 해상성능시험 결과 성능이 양호함을 확인하였으며, 통발 회수율은 100% 이었다. 3. 통발자동분리장치에 대한 해상성능시험 결과 성능이 양호함을 확인하였으며, 통발 분리율은 100% 이었다.

In the fishing process on the sea eel pots, the most dangerous and difficult labor is manually separating process of several thousand pots from main line with high speed hauling operation. In this study, the automatic separating system of the pot from main line is developed. This system is composed with the clip connected to the pot by branch line, the keeper attached to the main line by pressing and the separator separating the clip and the keeper. In the experiment, static and dynamic characteristics of the system are investigated. From the considerations on the experimental results, it is ascertained that the automatic separating system of the pot from main line proposed in this study has good operating performance.