• Journal of the Korean Magnetic Resonance Society
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• v.11 no.1
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• pp.56-63
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• 2007

A series of bromophenols and corresponding debrominated phenolic compounds was prepared by isolation from red alga Tichocarpus crinitus and by structural modification of natural bromophenols. Their structures were determined by extensive NMR analysis and the antioxidant activities were established through the determination of their abilities to inhibit free radicals using DPPH as the stable radical. The most active free radical scavengers were the debrominated phenolic derivatives 3,4-dihydroxybenzyl alcohol and 3,3',4,4'-tetrahydroxydiphenylmethane.

• 중국학논총
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• no.63
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• pp.343-362
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• 2019

During the traditional periods when there were exchanges among Korea, China and Japan based on ocean currents or seasonal winds, the southwestern coastal areas including Yeosu held an important position since the route would not have been complete without them. Armed with its advantages including the marine environment, the Yeosu area in the southwestern coast on the Korean Peninsula engage in active maritime exchanges and activities as a base along the sea route since the Neolithic or Bronze Age. It was the same later when Baekje and Gaya had exchanges with China and Japan, when Unified Silla had exchanges with China, and when Goryeo had exchanges with China and Japan. In Joseon, the Yeosu area gained fame as a marine defense base. In short, the Yeosu area in the southwestern coast on the Korean Peninsula during the traditional periods not only engage in active maritime exchanges and activities, but also serve as an important base that could not be left out in the maritime history of East Asia.

• Journal of the Korean Society of Marine Environment & Safety
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• v.14 no.1
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• pp.29-37
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• 2008

This study examined principles and techniques of efficient water quality management as well as total coastal pollutant loads and the relevant examples in the advanced countries from the viewpoints of water quality improvement and pollution control in coastal areas. The problems and improvements in an estimation of the current total pollutant loads were also pointed out. In addition, discussion was made on the relationship between total pollutant loads and environmental capacity as well as particulars requiring extensive examination on access to and study on water quality model used as prediction tool for marine environment. Furthermore, this study proposed details of and improvement plans for water quality control to be reflected and absorbed into systems and policies related to coastal water quality. In coastal areas, which are subject to total coastal pollutant loads, it is necessary to calculate pollutant loads reduction and allocation, to propose them in detail in statement in relations to new pollution sources for the corresponding projects or plans in environmental impact assessment and prior environmental review system. Also, in relations to regional plans for coastal management, the local government concerned must focus more on environmental management plan to implement data on pollution sources and pollutant loads flown into sea areas under basic jurisdiction, therefore it is required to actively respond to expansion and introduction of total coastal pollutant loads system in the future. Total coastal pollutant loads system must be expanded and executed by considering characteristics of sea area and changes in the environment of land. For pollution sources in land, the competent authorities in charge of coastal environment will need to initiatively administer supervision, monitoring activities and achieve integration and operation of the related laws by preparing legal bases for management system or adjusting the related laws.

• Korean Journal of Remote Sensing
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• v.39 no.4
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• pp.409-423
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• 2023

North Korea is carrying out reclamation activities in tidal flat areas distributed throughout the west coast. Previousremote sensing research on North Korean tidal flats either failsto reflect recent trends or focuses on identifying and analyzing tidal flats. Thisstudy aimsto quantify the impact of recent reclamation activitiesin North Korea's coastal areas and contribute knowledge useful for determining the best remote sensing methods for coastal areas with limited accessibility, such as those in North Korea. Using Landsat-8 OLI images from 2014-2022, we analyzed land cover changesin an area on the west coast of Pyeonganbuk-do where reclamation activities are underway. Unsupervised classification using the normalized difference water index and the random forest classification technique were each used to divide the study area into classification groups, and changes in their areas over time were analyzed. The resultsshow a clear decrease in the water area and a tendency to increase cultivated area,supporting the evidence that North Korea'sreclamation isfor agricultural land expansion.Along coasts behind seawalls, the water area decreased by nearly half, and the cultivated area increased by over 2,300%, indicating significant changes and highlighting the anthropogenic nature of the cover changes due to reclamation. Both methods demonstrated high accuracy, making them suitable for detecting cover changes caused by reclamation. It is expected that further quality research will be conducted through the use of high-resolution satellite images and by combining data from multiple satellites in the future.

• The Korean Journal of Ecology
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• v.20 no.5
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• pp.315-321
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• 1997

Peroxidase activities and isozyme patte군 of the pine needles (Pinus densiflora) were examined and compared in the coastal regions of Anmyum-Do(Choongnam, Taean-Gun) and inland regions of Shinchang-Myun(Choongnam, Asan-City). The pine needle peroxidase from Anmyum-Do showed approximately three times higher specfic activity than Shinchang pine needle peroxidase. The pine needle extracts of Anmyun-Do and Shinchang contained three anionic isoperoxidases, named A1, A2 and A3, when subjected to starch gel electrophoresis at pH 7.0. Cjationic isoperoxidases could not be found in both extracts., However, there existed unique isoperoxidase An only from the extracts of Anmyun-Do pine needles under the salinary environment. Moreover, the specific activities of catalase and glucose-6-phosphate dehydrogenase from Anmyun-Do, known for the inducible enzymes under the stress condition, were about 1.8 times higher than those of Shinchang pine needles. However, the specific activities of other enzymes did not show great differences between the two regions. Considering the above results of the higher specific activity of peroxidase and the unique expression of isoperoxidase An, pine needle peroxidase might involve in the defence mechanism against the salinary stress of Anmyun-Do.

• Fisheries and Aquatic Sciences
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• v.18 no.4
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• pp.349-357
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• 2015

To reutilize fisheries waste, we isolated a bacterial strain from a coastal area located in Busan. It was identified as Bacillus licheniformis TK3-Y. Using plate assay and 500-mL flask experiments, we found that the isolate simultaneously possessed cellulolytic, proteolytic, and lipolytic activities with salt tolerance. 10% (v/v) inoculums, were used to examine the biodegradation characteristics of the TK3-Y strain on carboxymethylcellulose, skim milk, and olive oil media. The optimum conditions for pH, temperature, agitation speed, and NaCl concentration on each 1% substrate were 6, $50^{\circ}C$, 180 rpm, and 17.5%, respectively. Under optimal conditions, the TK3-Y strain showed 1.07 U/mL cellulolytic, 1,426 U/mL proteolytic, and 6.45 U/mL lipolytic activities. Each enzyme was stable within a range of 17.5-35% NaCl. Therefore, the salt tolerance ability of strain TK3-Y was superior to other related strains. In degradation of a mixed medium containing all three substrates, both the cellulolytic and proteolytic activities were somewhat lower than those on each single substrate, while the lipolytic activity was somewhat higher. From the above results, the TK3-Y strain appears to be a good candidate for use in the efficient treatment of fisheries waste in which components are not collected separately.

• The Journal of Fisheries Business Administration
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• v.29 no.2
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• pp.21-46
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• 1998

The government is largely responsible for preventing “the tragedy of the common property”, but fisherman's effort fer an autonomous fishery control is equally required. Especially in these days of EEZ such self- regulated fishery management system should be developed and cared for as well. This study aimed to explore a proper management system for coastal fishing ground that now requires the responsible fisheries management by investigating and analysing more drastically the managerial functions of fishery right by Eochon-Gye(the smallest unit of fisheries cooperative based on a fishing village), a typical fishery producer's organization in Korea. This study also included such contents as (1) an understanding of fishery producer's organization, (2) the utilization and management system of coastal fishing ground, (3) the actual condition of fishing right distribution in Korea, (4) the fishery right management and activity of Eochon-Gye, (5) the operation and distinctive feature of fishery right in Japan, (6) the intervention and limit of fishery producer's organization for fishing ground management function, and (7) summary and proposal. We made all Eochon-Gye of the whole country an object of this study and carried out an investigation into Eochon-Gye through a questionnaire. We extracted 359 Eochon-Gye, 20% of the total 1,719 Eochon-Gye as a random sample and investigated these regions through a questionnaire by mail. The contents of the questions consist of 40 items, including six categories about the organization of eochon-gye, and fishing ground management and activities.

• Ocean and Polar Research
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• v.23 no.3
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• pp.279-284
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• 2001

The natural high productivity of temperate coastal waters in Korea can be used in advantage to reduce the feed costs for the cage-cultured marine carnivorous fish species. By using the night-lights methods an alternative of supplementary feeding strategy can be offered to the cage farmers and maintain sound environmental conditions that could enhance maximum sustainable yields. The aim of this study was to investigate the effects of night-lights which shown positive results on feeding and growth in sea cage cultured rockfish, Sebastes schlegeli. The study showed that for the water around overhead illuminated sea cage, higher zooplankton density was observed at night than during the daytime. Increased amounts of for-age, evidenced by stomach content analyses were observed in the early evening, but decreased amounts were observed in the morning and afternoon. That is, feeding activities of the fish were most intensive from midnight to dawn. In a three month feeding experiment, the results showed that night-lighted groups were superior to groups with the highest feeding efficient. This study suggested that the evidence that night-lights superimposed on only day-lights enhance growth of rockfish in sea cages during summer and winter, with timing of exposure affecting growth of juvenile fish. The capability to control the feeding behavior of marine life via manipulation and external stimuli could considerably benefit the advancement of sea cage aquaculture in coastal areas.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2001.09a
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• pp.92-96
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• 2001

Although the problem of seawater intrusion at the coastal aquifer was recognized before over one hundred years at the coastal aquifer, much groundwater keep on being salinitized by several reasons such as groundwater exhaustion, coastalline change, and human activities. The horizontal and vertical electrical soundings and geostatistical methods were used to define the local characteristics of saltwater intrusion and to estimate the saltwater interface in the southeastern area of the Pusan City. The 24 points of the Schlumberger vertical electrical soundings(VES) to loom depth and the 2 lines of dipole-dipole horizontal soundings are peformed. The resistivity data have lognormal distributions. The horizontal extents of saline water intrusion were estimated from the inversion of horizontal prospecting data. Lognormal ordinary kriging is used in A-A' resistivity profiles on May and July because the data have stationary models in semivariograms. Lognormal IRF-k kriging is used for the isopleth maps using vertical resistivity data. The 10 ohm-m resistivity line on the isopleth maps of 21m, 30m, 50m, and 70m depth using resisitivity data measured in July is sifted to the east, cpomparing that of the isopleth maps measured in May. The kriged vertical and horizontal resistivity isopleth maps suggested that the geostatistical methods can be used to define the variation of earth resistivity distribution at the saltwater interface.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.11 no.6
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• pp.177-182
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• 2011

These days as there are growing the number of vessel sailing, diverse aquaculture industries, fishing works, and leisure activities in coastal area, the diverse communication services have been required for secure voyage information. This paper addresses the scheme for costal area service using mobile IP router with multiple interfaces. For this, this system has the wireless interfaces, such as WiBro, HSDPA, and WLAN that can provides vessels with divers communication services, and can provide the vessels with the diverse information communication services in real-time through wireless communication network installed in costal area. So this can provide the infrastructure that supplies the authorized seamless information communication services.