• Journal of the Korea Society of Computer and Information
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• v.26 no.4
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• pp.113-118
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• 2021

In this paper, we propose an efficient dynamic workload balancing strategy which improves the performance of high-performance computing system. The key idea of this dynamic workload balancing strategy is to minimize execution time of each job and to maximize the system throughput by effectively using system resource such as CPU, memory. Also, this strategy dynamically allocates job by considering demanded memory size of executing job and workload status of each node. If an overload node occurs due to allocated job, the proposed scheme migrates job, executing in overload nodes, to another free nodes and reduces the waiting time and execution time of job by balancing workload of each node. Through simulation, we show that the proposed dynamic workload balancing strategy based on CPU, memory improves the performance of high-performance computing system compared to previous strategies.

• The Journal of Fisheries Business Administration
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• v.53 no.3
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• pp.65-83
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• 2022

In addition to simply providing quality food to the people, the fishery industry must be maintained and developed because it has various functions such as national food security, preservation of natural scenery, protection of national territory, and revitalization of the local economy. However, risk factors such as climate changes and environmental destruction have raised concerns about the sustainable development of the industry. Since these risk factors are becoming larger and more complex over time, it is time to conduct research related to the risk of the fishery industry. Therefore, the purpose of this study is to explore the risk factors facing the fisheries at this point, to analyze the economic ripple effect of regional fishery product supply shortage, and to draw implications. As a result of this study, the economic ripple effect of fishery product shortage per won was highest in Busan, followed by Gangwon, Gyeongnam, and Gyeongbuk. Considering the size of the local fishery industry, Busan had the highest supply shortage per 1% of local fisheries production. It is also necessary to prepare special risk management and countermeasures for these regions since the effect of supply shortage in regions such as Jeonnam, Gyeongnam, and Jeju is large compared to other regions.

• Journal of the Korean Geotechnical Society
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• v.22 no.11
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• pp.143-149
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• 2006

An experimental study was carried out to investigate the stabilizing capability of oyster shell binder, which was developed using waste oyster shell inducing environmental pollutions by piling up out at the open or the temporary reclamation. The purpose of this paper is to compare stabilinzing capability of oyster shell binder and cement binder with treated soils. For this, a series of compressive laboratory tests were peformed to evaluate strength characteristics of treated soils by both oyster shell binder and cement binder with varing water content of dredged soils, different mixing rates of binder and curing days. Based on test results, eco-friendly binder manufactured by oyster shells showed more stabilizing capacity than cement binder and is estimated as good resource materials for soft soil improvements.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.26 no.5
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• pp.285-291
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• 2014

The statistical information of the coastal water temperature monitoring data can be biased because of outliers and missing intervals. Though a number of outlier detection methods have been developed, their applications are very limited to the in-situ monitoring data because of the assumptions of the a prior information of the outliers and no-missing condition, and the excessive computational time for some methods. In this study, the practical robust method is developed that can be efficiently and effectively detect the outliers in case of the big-data. This model is composed of these two parts, one part is the construction part of the approximate components of the monitoring data using the robust smoothing and data re-sampling method, and the other part is the main iterative outlier detection part using the detailed components of the data estimated by the approximate components. This model is tested using the two-years 5-minute interval water temperature data in Lake Saemangeum. It can be estimated that the outlier proportion of the data is about 1.6-3.7%. It shows that most of the outliers in the data are detected and removed with satisfaction by the model. In order to effectively detect and remove the outliers, the outlier detection using the long-span smoothing should be applied earlier than that using the short-span smoothing.

• Journal of fish pathology
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• v.24 no.3
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• pp.197-204
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• 2011

The edible ascidian Halocynthia roretzi is a commercially important fisheries resource in Korea. However, for the last several years, outbreaks of mass mortalities of the species have been occurring along the south and east coasts of Korea, where most ascidians are produced. Although it is known that tunic-softness syndrome is associated with these mortality events, the agent causing the syndrome has not yet been confirmed. To determine the agent causing tunic-softness syndrome, healthy and diseased ascidians were collected in March 2011 from Tongyeong, on the south coast of Korea, and were used for biological and pathological investigations. The results showed that diseased ascidians exhibited remarkably reduced body fluid, fatness index, and tunic index compared with healthy specimens. Interestingly, bi-flagellated protozoans were observed specifically in the tissue imprints and tunic cultures of diseased ascidians at an occurrence rate of 97.5%. Histological observation showed that the thickness of the tunics of diseased ascidians was reduced by half, and irregular structure and breakdown of the tunic fiber bundles were observed. In particular, flagellate-like cells were observed in the diseased ascidians. Our study clearly shows that bi-flagellated protists are present only in the softened ascidians, suggesting that the flagellates are partly or entirely associated with soft-tunic syndrome. Accordingly, further investigations to verify the effects of the flagellates found in the present study on soft-tunic syndrome should be conducted.

• Journal of Navigation and Port Research
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• v.40 no.4
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• pp.223-230
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• 2016

While marine transport freight is steadily increasing, people are more interested in terminals handling cargo. But the domestic researches on terminals were almost on container terminal. This study attempted to study the service quality for bulk terminals. The users of bulk terminal services were divided into shipowners and shippers to compare their differences by using bulk terminal service provided. During the attributions proposed in this study, Tangibles were descripted by the numbers of berth or depth, facilities, and so on. So it was suitable to consider the tangibles by formative indicators. And also this study has tried using "reflective model" and "formative model" to make a measurement model for comprehensive analyses. The results showed that all of the items were significant except the relation between empathy and performance satisfaction in the overall measurement model analyses. User groups difference analyses results have showed that the trust responsiveness impact on performance satisfaction was more importantly assessed by shippers than by shipowners. It was expected to use the results of this study as a good strategic resource to help bulk terminal administrators make various expansion plans to improve the bulk terminal's competitiveness in the future.

• Ocean and Polar Research
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• v.31 no.1
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• pp.31-50
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• 2009

The demarcation of Maritime Boundary is directly related to the expansion of jurisdiction and the securing of resources. Resource diplomacies of the three countries Korea, China and Japan represent a major task for the national administrations : to secure resources as well as to stablize and sustain resources for future national economies. At the sea area around Korea as well, countries are fiercely competing to secure resources and to expand jurisdiction. This is evidenced by the fact that various principles and logics which are beneficial to each own country are presented through international precedents, agreement between countries and the theories of the international law scholars. They say that the conclusion of demarcation of maritime boundary for the Yellow Sea would be easy from the point that there is no dispute related to island dominion in the waters of the Korean Peninsula especially the Yellow Sea, but still we need to have a strategic approach to this issue from the point that the factors used for claiming maritime boundaries may expand the waters of a country over much. For example, the continental shelf boundary in consideration of the distribution of sedimentary deposits in the Yellow Sea which is being raised by China began from the hypothesis that the inflow of sedimentary deposits to the Yellow Sea through the rivers of China represents absolute majority, but the results of the latest studies raised questions on the hypothesis. Especially, the studies done by Martin and Yang revealed that the inflow of sedimentary deposits to the Yellow Sea from the Yellow River is approximately less than 1% of total sedimentary deposits in the Yellow Sea, and also the result of analysis on the causes and counter policy measures on the environment of Bohai, China supports the reliability of the results of such studies. From a legal aspect, the sedimentary deposits of rivers which are claimed by China represent extremely weak ground for the claim for the title of the continental shelf. The siltline claimed by China seems to be based on the Article 76-4-(a)(i) of UNCLOS. This is, however, not the definition on the title of the continental shelf but it is only a technical formula to utilize in a case where a country desires to expand the continental shelf to over 200 nautical miles. Scientific and Technical Guidelines of the Commission on the Limits of the Continental Shelf also confirm this point through the Article 2.1.2 of the Guideline. The only case in which sedimentary deposits of rivers were referred to as concrete demarcation of maritime boundary was in the which was concluded in 1986 between India and Myanmar at the Andaman Sea. In the said case, India acknowledged the boundary up to the isobath of 200m which Myanmar claimed based on the sedimentary deposits of the Irrawaddy River. It has limits as a case for acknowledging the sedimentary deposits, however, because in fact India's acknowledgment was made in exchange for the condition that Myanmar gave up the dominion of two islands which they had been claiming from India up until that time.

• Journal of the Korean Society for Marine Environment & Energy
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• v.15 no.1
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• pp.54-65
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• 2012

While fishery has been continuously suffering from deteriorating economic feasibility, the amount of the deposited marine litter has been increasing due to an increased number of marine leisure tourists which are caused by an improved quality of life and five-day work week. In addition, the fishery area has been reduced by the reclamation projects and it is being destroyed by marine pollution with a variety of contaminants coming from land and sea. To protect and improve fisheries in these poor conditions, Korean governments have implemented the submerged marine litter collection projects. However, previous research results on the marine environment and resources indicate that it requires a lot of time investment to achieve tangible results of such improvement. The 300 billion won marine environment and resource investigation project has been executed since July 2004 by Korean governments, which demands strategic approaches to obtain more effective and satisfactory results before the project expires in 2013. Ocean environment research institutes and governments need to cooperate each other to gain efficient and reasonable achievement by identifying and linking related projects. This study suggests that the marine environment and resources investigation projects should run parallel with the submerged marine litter collection projects on mutually agreed research items in the identical area of the ocean to obtain cost-effective improvement of marine environment and fishery conditions.

• Korean Journal of Ecology and Environment
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• v.53 no.1
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• pp.46-54
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• 2020

Artificial and natural changes such as weir construction and climate change often cause abnormal blooming of organism. Therefore, variations in species community of organisms have been actively investigated to identify influential environmental changes on the fresh water ecosystem. In this study, we investigated Chironomidae community and environmental factors at 5 representative weirs (Ipo, IP; Sejong, SJ; Juksan, JS; Gangjeong-goryung, GG; and Dalsung weir) in 4 Korean major rivers to figure out relationship between Chironomidae community and environmental factors. Environmental factors indicating organic matter (total organic carbon, TOC and Chlorophyll-a, Chl-a) showed lower concentration in IP and SJ compared with other sites(JS, GG and DS). 3 sub-family 18 genus 25 species of Chironomidae community were found in this study. Among them, Chironominae was dominant in JS (Tanytarsus sp.1), GG (Polypedilum scalaenum) and DS (Polypedilum scalaenum), while different sub-family were dominant in IP (Orthcladinae, Tokunagayusurika akamushi) and SJ (Tanypodinae, Tanypus punctipennis). Moreover, based on the dominant species of Chironomidae community and environmental factors, the cluster analysis classified our study sites into 3 groups. These results imply that the diet resource is the most important factor for dominance of Chironomidae in Korean rivers. We also suggest that further study on the identification of diet resources for each Chironomidae specie is required for better understating of distribution in species community of Chironomidae at various ecosystems.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.4
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• pp.222-230
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• 2016

HEMIRE is a 6,000-meter-class remotely operated vehicle (ROV) that has been developed for observation and sampling of objects of interest on the deep seabed. We first carried out deep-seabed exploration around the slopes of the Hupo Bank and the Ulleung Basin in the East Sea in June 2015. Over two weeks, a total of 10 dives were made from a support ship, the R/V Onnuri, at eight stations with water depth ranging between 194 and 2,080 m. The dive times ranged from 1 to 6 hours, depending on the operating conditions. We obtained the following results: 1) video images of the deep seafloor; 2) red snow crab density data (a major fishery resource) and inventories of deep-sea fauna, including an unrecorded organism; 3) specific topographies such as canyons slopes; 4) an undisturbed sediment core obtained using a push corer; and 5) observations of the seabed surface covered with discarded anthropogenic waste material.