• Journal of Internet of Things and Convergence
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• v.2 no.3
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• pp.31-35
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• 2016

IoT technologies have been rapidly developed in recent years, and applied to many industries. In the field of fisheries, the water quality management system have been developed, helping in improving productivity and working environment. In this paper, we have designed the smart feeding system, interoperable with the water quality system, using LPWA network. LPWA network is an IoT network, which is appropriate to fish farms because of its wide area coverages and low power consumption. We expect this work to contribute to developing the aquaculture technology through the big data analysis with the accumulated data.

• Journal of Internet of Things and Convergence
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• v.2 no.4
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• pp.9-14
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• 2016

The range of use of drones is gradually expanding from military to commercial applications. In the field of agriculture, there have been many studies to utilize drones, but there have been relatively few efforts to utilize drones in the marine and fisheries sectors. In this paper, we propose drones and system requirements for marine and fisheries applications. Marine and fisheries monitoring using drones is expected to be more effective and cost effective than existing methods.

• Proceedings of KOSOMES biannual meeting
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• 2007.11a
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• pp.87-89
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• 2007

선행 연구개발한 집단감시 디지털 시스템(Group Digital Surveillance System for Fishery Safety and Security, GDSS- F2S)은 대단위 양식장에 침입하는 도적을 방어하기 위하여 레이더 추적정보와 적아식별 정보를 제공하는 시스템이다. 그러나 GDSS-F2S에서 제공하는 두 가지 정보만으로는 도적행위를 입증할 수 있는 법적 증거자료로 미흡하다. 본 논문에서는 이러한 문제점 해결방안의 하나로 CCD 카메라를 이용한 영상획득 장치를 개발하여 GDSS-F2S에 부가한 연구내용을 기술한다. 영상획득 장치 개발에 앞서, 실험지역의 지리적인 특성을 고려한 도적침입 예상경로 분석과 도적행위 시나리오를 기반으로 유효한 대응수단을 검토한 결과, 영상획득 장치가 유효한 대응수단임을 확인하였다. 영상획득 장치는 저가이변서 성능이 우수한 0.0001 룩스의 초저조도 CCD 카메라와 부가장치를 이용하여 개발하였다. 6개월 이상의 장기 현장실험을 통하여 본 연구에서 개발한 시스템을 평가한 결과, 주간은 물론 1 미터 앞도 식별할 수 없는 야간에도 차량의 행동과 번호판 및 사람의 행동과 인상착의 등의 영상정보를 확보할 수 있었다.

• Journal of Aquaculture
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• v.15 no.2
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• pp.79-86
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• 2002

This study is the first attempt to understand the feeding physiology of a sea-urchin larva on a red-tide dinoflagellate. Fifteen day old larvae of S. intermedius capture C. polykrikoides cells by localized reversal of ciliary beats. No failure to transporte the algal cells from theciliated band to mouth and no rejection at the mouth suggest that C. polykrikoides has no feeding deterrence to S. intermedius larvae. The trend obtained for the clearance rate of S. intermedius larvae is similar to that of other sea urchin larvae. Thus, the clearance rate decreased as the algal concentration increased. Maximum clearance rate of S. intermedius on C. polykrikoides was 17.7 $\mu l$/larva/hr. Ingestion rate rapidly increased at lower algal concentrations and saturated at higher concentrations. There was no inhibition in ingestion rate at the highest prey concentration of ca. 3000 cells/ml. Maximum ingestion rate of S. intermedius on C. polykrikoides was 131 ngC/larva/d, which is higher than that reported for the larvae of the mussel Mytilus gal-lotrovincialis, but lower than that of the ciliate Strombidinopsis sp. The grazing rate, calculated by combining the field data on algal abundances with experimental data on ingestion rate, suggests that due to its low abundance, sea urchin Iarva has no significant grazing impact on C. polykrikoides population.

• Fisheries and Aquatic Sciences
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• v.7 no.4
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• pp.175-183
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• 2004

The dinoflagellate Alexandrium tamiyavanichii Balech, a producer of toxins causing paralytic shellfish poisoning (PSP), has recently been considered as one of main organisms responsible for toxication of shellfish in Japan. In this study, A. tamiyavanichii was subjected to a molecular phylogenetic analysis inferred from 28S rDNA D1-D2 sequences and a species-specific LSU rRNA-targeted oligonucleotide DNA probe was designed to identify A. tamiyavanichii using the whole cell-FISH (fluorescence in situ hybridization). The sequences of the 28S rDNA D1-D2 region of A. tamiyavanichii showed no difference from A. cohorticular AF1746l4 (present name A. tamiyavanichii) and formed a distinct clade from the 'tamarensis species complex'. The probe, TAMID2, reacted specifically with A. tamiyavanichii cultured cells, without any cross-reaction with other species belonging to the same genus, including A. tamarense, A. catenella, A. affine, A. fraterculus, A. insuetum and A. pseudogonyaulax. In a test of cross-reactivity with a field sample, TAMID2 reacted consistently with only A. tamiyavanichii, indicating that the present protocol involving the TAMID2 probe might be useful for detecting toxic A. tamiyavanichii in a simple and rapid manner.

• The Korean Journal of Malacology
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• v.28 no.2
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• pp.81-90
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• 2012

The neritid species Clithon retropictus inhabits rivers and estuaries along the southern coast of the Korean mainland but has not been previously reported from Jeju Island. In 2007 and 2011 specimens of this species were obtained from two separate localities on the south coast of the island. Comparisons were made with von Martens' original description, specimens from the Korean mainland, and illustrations and descriptions in the literature. Although there were some differences in color and markings, and slight differences in morphology, the specimens from Jeju Island compare well with those from the mainland and in the literature. The shells of this species become more ovate and more eroded with age. In one locality, a small river, specimens of the pleurocerid Semisulcospira libertina (Gould, 1859), were found adjacent to, and coexisting with, a population of C. retropictus, an association that often occurs. The occurrence of Clithon retropictus represents a range extension to Jeju Island.

• The Korean Journal of Malacology
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• v.23 no.1
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• pp.65-104
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• 2007

This catalogue is the result of a four-year survey of the mollusks of Jeju Island, the southernmost island in the Republic of Korea. Forty-eight survey stations were visited, with a total of 82 specific localities being sampled. Literature records were also obtained. Local and world distribution of each species is included. This survey reports a total of 1,072 mollusk species and subspecies; 1,015 marine and 57 land and freshwater. There are 812 gastropods, of which 755 are either entirely marine or have marine affinities. The best represented of the marine families are the Pyramidellidae, Trochidae, and Ovulidae. There are 225 bivalves, none being freshwater species, with the Veneridae, Mytilidae, and Arcidae having the largest number of species. Among the smaller classes there are sixteen Cephalopoda, eleven Polyplacophora, and eight Scaphopoda. Compared to mainland Korea, Jeju Island has a rather small terrestrial mollusk fauna and a depauperate freshwater one, with mainly Palearctic connections. The Helixarionidae and Bradybaenidae are the largest terrestrial families. The marine faunal affinities with the neighboring Japonic and Indo-West Pacific provinces are also discussed, revealing that this island's mollusk fauna is a blend of warm-temperate and subtropical-tropical species.

• Proceedings of the KSRS Conference
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• 2003.11a
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• pp.37-37
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• 2003

Rice is one of the most important crop in the world and is a major export of Thailand. Optical sensors are not useful for rice monitoring, because most cultivated areas are often obscured by cloud during the growing period, especially in South East Asia. Spaceborne Synthetic Aperture Radar (SAR) such as RADARSAT, can see through regardless of weather condition which make it possible to monitor rice growth and to retrieve rice acreage, using the unique temporal signature of rice fields. This paper presents the result of a study of examining the backscatter behavior of rice using multi-temporal RADARSAT dataset. Ground measurements of paddy parameters and water and soil condition were collected. The ground truth information was also used to identify mature rice crops, orchard, road, residence, and aquaculture ponds. Land use class distributions from the RADARSAT image were analyzed. Comparison of the mean DB of each land use class indicated significant differences. Schematic representation of temporal backscatter of rice crop were plotted. Based on the study carried out in Pathum Thani Province test site, the results showed variation of sigma naught from first tillering vegatative phase until ripenning phase. It is suggested that at least, three radar data acquisitions taken at 3 stages of rice growth circle namely; those are at the beginning of rice growth when the field is still covered with water, in the ear differentiation period, and at the beginning of the harvest season, are required for rice monitoring. This pilot project was an experimental one aiming at future operational rice monitoring and potential yield predicttion.

• Fisheries and Aquatic Sciences
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• v.26 no.10
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• pp.605-616
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• 2023

Scuticociliatosis, caused by the parasitic pathogen Miamiensis avidus, poses a significant threat to olive flounder farms in South Korea. Infected fish suffer from severe systemic infections affecting various organs, with potential secondary bacterial diseases. This study investigated the emergence of different M. avidus serotypes in 20 olive flounder farms on Jeju island, South Korea, from 2015 to 2020. Additionally, we identified Tenacibaculum maritimum as a co-infecting bacteria. Based on serotyping and monitoring data, we developed a trivalent vaccine targeting two serotypes of M. avidus and one strain of T. maritimum. The efficacy of the vaccine was evaluated under laboratory conditions and demonstrated a relative percentage of survival (RPS) of 75%, 80%, and 93% for M. avidus serotype I, M. avidus serotype II and T. maritimum, respectively. Furthermore, successful field trials conducted on four different olive flounder farms resulted in significantly higher survival rates (52%-76% RPS) and weight gains in vaccinated fish. Overall, this study presents an effective vaccine against M. avidus and T. maritimum infections in farmed olive flounder, making a valuable contribution to sustainable aquaculture in South Korea.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.42 no.4
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• pp.234-239
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• 2006

This paper introduces an auto-feeding system to exactly control the feeding time and the amount to cultured fishes in aquaculture industrial field. To reduce expensive costs or labors in this field, it was designed by the concept of controlling feed quantity exactly on the basis of fish's feeding behavior pattern in water tank. A feed control method of this system was developed for controlling feed amount by rotor capacity and motor rotated number. Moreover, a scattering section was selected by rotate way of propeller wing to scatter dried feed to designated site, and then, the diameter of its wing was 250mm and maximum scattering distance was 7.6m for 600rpm. Furthermore, the scattering ways were embodied 2 types such as a simplified way and a multistage shift way looks like a manual scattering. As a results, the multistage shift way is more effective to discharge the dried feed widely than the simple way in the water tank.