• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.30 no.4
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• pp.251-262
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• 1994

The speed of vertical migration and the volume backscattering strength of the scattering layers during the evening and morning transitions between day and night were measured in November 1990-1992 in thermally stratified waters of the East China Sea. Acoustical measurements were carried out using a scientific echo-sounder operating at t재 frequencies of 25 and 100kHz, and using an echo-integration system connected with a micro-computer. Biological sampling was accomplished by bottom trawling to identify fish species recorded on the echo sounder, and the species and length compositions were determined. The values of scattering strength were allocated to group of fishes according to the fish traces on the echo recording paper and the species composition of trawl catches. The vertical velocities of migration derived from the changes in the depths and the values of peak scattering strength of the dense layer vertically migrating toward the bottom or toward the surface. The trawl data suggest that snailfish and fishing frog were the most abundant fishes in all research stations. As sunrise approached, the fish formed a strong concentration just above the thermocline. The the highest values of scattering strength in the entire water column appeared in the depth strata above the thermocline just before the begining of downward migration. As soon as the fish began to migrate downwards across the thermocline, the values of the scattering strength in the depth strata above the thermocline rapidly decreased, while the values for the scattering layer moving slowly toward the bottom gradually increased. During the 1992 surveys, the speed of the vertical migration was estimated to be 0.38m/min in the upward migration and 0.32m/min in the downward migration, respectively. That is the rate of vertical migration was slightly higher at dusk than at dawn. Similar migration patterns were observed on different stations and under different weather conditions during the surveys in 1990.

• Journal of Ecology and Environment
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• v.30 no.1
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• pp.23-38
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• 2007

Based on a time series of ocean climate indices and catch records for seven pelagic fish species in the Tsushima Warm Current (TWC) and Kuroshio-Oyashio Current (KOC) regions from 1910 to 2004, we detected regional synchrony in the long-term fluctuations of the fish populations and identified alternation patterns of dominant species related to climate shifts. The annual catches of Pacific herring, Japanese sardines, Japanese anchovies, jack mackerel, chub mackerel, Pacific saury and common squid in the TWC region fluctuated in phase with those in the KOC region, which suggests that they were controlled by the same basin-wide climate forcing. After the collapse of the herring fishery, the alternation sequence was: sardines (1930s), Pacific saury, jack mackerel, common squid and anchovies ($1950s{\sim}1960s$), herring ($late\;1960s{\sim}early\;1970s$), chub mackerel (1970s) and then sardines (1980s). As sardine biomass decreased in the late stages of the cool regime, catch of the other four species increased immediately during the warm period of the 1990s. Regional differences in the amplitude of long-term catch fluctuations for the seven pelagic fishes could be explained by regional differences in availability, fishing techniques and activity.

• Proceedings of the KAIS Fall Conference
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• 2010.05b
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• pp.937-940
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• 2010

21세기 정보화 세계화 사회에서 창의적이고 자율적인 인간양성을 위한 교육개혁으로 창의적 인재양성, 자기주도적 학습능력 배양이 강조되어지고 있다. 그럼에도 불구하고 제주지역 농어촌의 경우 인구 집중이 도시로 이루어지면서 농어촌의 인구가 감소되어지고 그러한 결과로 소규모 학교는 통폐합이되면서 교육여건은 악화되고 있는 실정이다. 이에 제주지역 농어촌 교육문제를 해소하여 학생들의 이농현상을 줄일 수 있으며, 창의적이고 자기주도적인 학습 능력을 배양할 수 있는 프로그램 개발의 필요성을 느끼게 되었다. 본 연구에서는 도시와 농어촌의 서로 다른 교육여건에 기반하여 교육내용을 특성화함으로써 제주지역 농어촌 학생의 창의적 문제해결력 향상을 위한 통섭적 활동 모형과 프로그램을 개발하기 위한 이론적 고찰을 하였다. 도시와 농어촌의 학력격차를 해소하기 위해서는 농어촌 학생에게 적절한 교육내용과 활동으로 재편성하여 가르칠 필요가 있다. 특히 제주도는 농촌과 어촌, 도시형이 특별히 구분되어지는 것이 아니라 하나의 통합된 생활문화의 특징을 가지고 있다. 앞으로 본 연구의 이론적 고찰을 바탕으로 제주지역 농어촌 학생들의 일상적인 생활환경에서 접하게 되는 다양한 활동 속에서 창의적으로 문제해결을 할 수 있도록 통섭적 활동 모형과 프로그램을 개발하여 적용하게 되면 학생의 역량을 강화시키고 잠재해 있는 창의적 문제해결력을 개발하여 학력향상에 기여할 수 있을 것이다.

• Proceedings of the Microbiological Society of Korea Conference
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• 2006.05a
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• pp.29-31
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• 2006

In a previous report, we showed that enzyme $IIA^{Glc}(EIIA^{Glc}$ of Escherichia coli phosphotransferase system (PTS) interacts with and regulates activity of FrsA (fermentation/respiration switch protein). A BLAST search revealed that orthologs of FrsA exist only in some Gram-negative bacteria such as E. coli, Salmonella typhimurium, Shigella flexneri, Yersinia pestis, Vibrio cholerae, Vibrio vulnificus, Vibrio parahemeolyticus, and Photorhabdus luminescens and all of these species are facultative anaerobes belonging to the ${\gamma}-proteobacterial$ group, and most of them are highly pathogenic. Ligand-fishing experiments using $EIIA^{Glc}$ of Vibrio vulnificus ($vEIIA^{Glc}$) as bait revealed that $vEIIA^{Glc}$ also interacts with vFrsA in a phosphorylation state-dependent manner. The frsA mutant of Vibrio vulnificus showed remarkably reduced cytotoxicity to HeLa cells and reduced lethality to mice compared to wild type. Comparison of extracellular proteomes between the mutant and wild type indicated that hemolysin was not produced in the frsA mutant. Characterization of another protein interacting with $vEIIA^{Glc}$ will be discussed.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.54 no.2
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• pp.194-207
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• 2021

It is necessary to assess and manage the different elements of the marine ecosystem, such as climate change, habitat, primary and secondary production, energy flow, food web, potential yield, and fishing, to maintain the health of the ecosystem as well as support sustainable development of fishery. We set up an ecosystem model around the Korean peninsula to produce scientific predictions necessary for the assessment and management of marine ecosystems and presented the usability of the model with scenario experiments. We used the Atlantis ecosystem model based on the marine food web; Atlantis is a three-dimensional end-to-end model that includes the information and processes within an entire system, from an abiotic environment to human activity. We input the ecological and biological parameters, such as growth, mortality, spawning, recruitment, and migration, to the Atlantis model via functional groups using existing research and local measurements. During the simulation period (2018-2019), we confirmed that the model reproduced the observed data reasonably and reflected the actual ecosystem characteristics appropriately. We thus identified the usability of a marine ecosystem model with experiments on different environmental change scenarios.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.22 no.5
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• pp.199-206
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• 2021

This paper describes the feasibility and reliability verification of installing a protective structure to protect attack periscopes. The attack periscope is the critical equipment of a submarine to enable the user to monitor surface and air activity, collect navigational data, and detect and identify targets. The attack periscope provides target information acquired through TV, IR camera, and laser range finder to the combat system. In the product improvement program, the upper part of the masts was exposed to the outside of the sail because the existing attack periscope was replaced with a new one. On the other hand, the head sensor can be damaged by floating objects, such as fishing nets, during sea navigation. Therefore, the installation of a protective structure for an attack periscope improved the equipment operation performance. The feasibility and reliability of the installation of the protective structure were verified by examining the influence of URN.

• Journal of Korean Society of Rural Planning
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• v.29 no.1
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• pp.29-35
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• 2023

Although Due to industrial development and urbanization, the number of schools closing due to a decrease in the school-age population is increasing due to the phenomenon of relocation from farming and fishing villages. Closing schools are used as social and cultural facilities, or they are used to generate income by providing education and experiences. Agro-healing is an activity that promotes psychological, social, and physical health by using rural resources. By reflecting the Agro-healing in the services operated by the closed school, the perception of the provision of the Agro-healing service was investigated as a way to provide a therapeutic service to visitors and to increase the utilization of the closed school. The questionnaire consisted of 10 questions, a total of 5 questions related to demographic information, a total of 5 questions related to the perception of agro-healing activities in closed school facilities. As a result, 347 people participated in the survey. The higher the awareness of agro-healing, the need for a agro-healing expert, the satisfaction with the use of rural closed school facilities, and the willingness to participate in agro-healing activities, the higher the awareness that the provision of agro-healing services was necessary by the state. Theses results are expected to be useful as basic to data to solve the diverse limitation in rural closed school and agro-healing activities.

• Proceedings of the Korean Society of Computer Information Conference
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• 2023.01a
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• pp.439-441
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• 2023

National park is one of the important types of protected area management systems established by IUCN and a management model for effective conservation and sustainable use of natural and cultural heritage in countries around the world, and it assumes important roles in conservation, scientific research, education, recreation and driving community development. This study takes Liaohe National Park in China, a typical representative of global coastal wetlands, as a case study, and uses python technology to collect travelogues and reviews of visitors from Mafengwo.com, Ctrip.com, Go.com, Meituan.com and Dianping.com as a source, and the text spans from 2015 to 2022. The results show that wildlife resources, natural landscape with river and sea, wetland ecology and fishing and hunting culture of northern China are fully reflected in the perceptions of visitors to Liaohe National Park. However, there is still much room for improvement in terms of supporting services and facilities, public education and tourists' experience and participation in Liaohe National Park. In this paper, we use python data visualization technology to study the public perception of wetland wildlife as the theme, and grasp the satisfaction, spatial distribution, activity content and emotional tendency of the public in the process of wetland wildlife as the theme, so as to better promote the Liaohe National Park to better carry out the public experience while strictly adhering to ecological protection, and to provide the Liaohe National Park with a better opportunity to This will provide scientific basis for the Liaohe National Park to play a better role in ecological civilization construction and education of ecological civilization awareness.

• Fisheries and Aquatic Sciences
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• v.27 no.6
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• pp.356-365
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• 2024

The study was conducted in the Terie River between January and April 2022. The objectives of the study were to assess the fish species composition, determine the length-weight relationship and condition factor and assess the water quality of the river using international water quality guideline for aquatic life. Gillnets with different mesh sizes, 4, 6, 8 and 10 cm were used to collect fish specimens in both dry and wet seasons. Immediately after capture, the total length (TL) and total weight (TW) of each individual were measured in centimeters and grams, respectively, and their relationship was determined using the power function. The physicochemical water quality parameters were analyzed using standard procedures and wagtech portable water quality Kits and Secchi Disk apparatus. A total of 667 fish specimens were collected from the Terie River, 410 and 257 in dry and wet seasons respectively. A total of six fish species, Oreochromis niloticus, Labeobarbus intermedius, Labeobarbus nedgia, Labeobarbus beso, Clarias gariepinus, and Ramius loti were recorded. For length-weight relationship and condition factor analysis, more abundant fish species (O. niloticus and L. intermedius) which were found in both seasons were selected. The length and weight relationship of L. intermedius were TW = 0.0073TL^3.04 in dry and TW = 0.0337TL^2.59 in we season indicated isometric and negative allometric growth respectively. While O. niloticus showed negative allometric growth, TW = 0.096TL^2.44 and TW = 0.0335 TL^2.76 in dry and wet seasons, respectively. The mean Fulton condition factor (FCF) of L. intermidus were 0.85 ± 0.03 and 0.94 ± 0.25 in dry and wet seasons, respectively. The FCF of O. niloticus was 1.70 ± 0.13 and 1.73 ± 0.12 in dry and wet seasons respectively. Except for ammonia, the physicochemical water quality parameters were with the permissible limit for aquatic life and are suitable for fishes Terie River. The river has commercially important fish specimens that could be used for food security and livelihood improvement. However, there is very limited fishing activity in the river due to less awareness on the value of fishes. Therefore, sustainable fishery development should be done in the river.

• Journal of the Korean Society for Marine Environment & Energy
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• v.11 no.3
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• pp.150-159
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• 2008

The marine litter generated as by-products of human activities and economic development enters to the sea through rivers or stream Indirectly, and through sea-based activities directly. It is commonly comprised of materials that degrade very slowly, such as various plastic products, polystyrene, glass, rubber, metal, wood, derelict fishing nets, wire, rope and so on. Such litter is found in the water column and on the seafloor as well as coastal areas In the Northwest Pacific region. It causes injury or death of human and other living organisms and also accident or damage of the vessel. It is not only a problem of country but also regional and/or global problem because it is transported by currents and winds from one country to another. In this regard, Northwest Pacific Action Plan (NOWPAP) Marine Litter Activity (MALITA) project had been carried out during 2006-2007 biennium and NOWPAP Regional Action Plan on Marine Litter (RAP MALI) has been also continuously implemented in the 2008-2009 biennium as next phase step of MALITA. MERRAC, one of four Regional Activity Centres (RACs) of NOWPAP, has developed monitoring guidelines, sectoral guidelines, and brochures related to sea-based marine litter and port reception facilities and services through MALITA project. Based upon these output, MERRAC will continuously implement relevant activities of RAP MALI in order to help to establish and improve a regional mechanism to deal with the sea-based marine litter problem. This paper aims to introduce MERRAC activities under MALITA and RAP MALI, and to suggest several recommendations to reduce marine litter in the NOWPAP region.