• 제목/요약/키워드: marine scientific research

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Impact of aggressive exposure conditions on sustainable durability, strength development and chloride diffusivity of high performance concrete

  • Al-Bahar, Suad;Husain, A.
    • Structural Monitoring and Maintenance
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    • v.2 no.1
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    • pp.35-48
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    • 2015
  • The main objective of this study is to evaluate the long-term performance of various concrete composites in natural marine environment prevailing in the Gulf region. Durability assessment studies of such nature are usually carried out under aggressive environments that constitute seawater, chloride and sulfate laden soils and wind, and groundwater conditions. These studies are very vital for sustainable development of marine and off shore reinforced concrete structures of industrial design such as petroleum installations. First round of testing and evaluation, which is presented in this paper, were performed by standard tests under laboratory conditions. Laboratory results presented in this paper will be corroborated with test outcome of ongoing three years field exposure conditions. The field study will include different parameters of investigation for high performance concrete including corrosion inhibitors, type of reinforcement, natural and industrial pozzolanic additives, water to cement ratio, water type, cover thickness, curing conditions, and concrete coatings. Like the laboratory specimens, samples in the field will be monitored for corrosion induced deterioration signs and for any signs of failureover initial period ofthree years. In this paper, laboratory results pertaining to microsilica (SF), ground granulated blast furnace slag (GGBS), epoxy coated rebars and calcium nitrite corrosion inhibitor are very conclusive. Results affirmed that the supplementary cementing materials such as GGBS and SF significantly impacted and enhanced concrete resistivity to chloride ions penetration and hence decrease the corrosion activities on steel bars protected by such concretes. As for epoxy coated rebars applications under high chloride laden conditions, results showed great concern to integrity of the epoxy coating layer on the bar and its stability. On the other hand corrosion inhibiting admixtures such as calcium nitrite proved to be more effective when used in combination with the pozzolanic additives such as GGBS and microsilica.

Review of the Scientific Name and Redescription of the Banded Moray Eel, Previously Reported as Gymnothorax reticularis (Muraenidae, Anguilliformes) in Korea (우리나라에서 과거 Gymnothorax reticularis로 보고된 나망곰치의 학명 검토 및 재기재)

  • Kim, Sung Yeon;Ji, Hwan Sung;Kim, Jin-Koo
    • Korean Journal of Ichthyology
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    • v.24 no.4
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    • pp.292-296
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    • 2012
  • The banded moray eel, previously reported as Gymnothorax reticularis, is redescribed based on one specimen (469.0 mm TL) collected from a fish trap in Geoje-do, South Sea, Korea. It is characterized by 19 dark brown vertical bars; 139 total vertebrae; both jaw teeth large, strong, and slightly serrated; 1 median intermaxillary tooth; small and blunt vomerine teeth. Although the banded moray eel has been reported as Gymnothorax reticularis in Korea by some ichthyologists, this study suggests that its scientific name should be changed to Gymnothorax minor based on its number of vertebrae and presence of a median intermaxillary tooth.

A Study on the Domestic Trends and Development Strategies of Marine Energy Research in South Korea (국내 해양에너지 연구동향 및 발전 전략에 관한 연구)

  • Sang-Hee Lee;Jin-Hoo Kim;Sung-Bo Kim
    • Journal of the Korean Society of Industry Convergence
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    • v.27 no.1
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    • pp.173-182
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    • 2024
  • While the current share of marine energy in South Korea is less than 1%, it is globally recognized as a resource approximately four times the annual electricity production. Considering the diverse geographical features of the East Sea, South Sea, and West Sea, marine energy development is crucial for South Korea and essential for achieving the 2050 carbon neutrality goal. Policy efforts for marine energy deployment focus on establishing an innovative, open, and integrated R&D system to respond flexibly. The construction of a scientific, economic, and social valid site selection system, along with a maritime spatial planning regime that considers environmental and socio-economic impacts, is emphasized. To expedite the early activation of marine energy, comprehensive policy endeavors, including discriminatory support policies and participation in international standardization, are anticipated to contribute to the sustainable development and dissemination of marine energy. Marine renewable energy plays a significant role in sustainability and addressing climate change, considered an essential component of South Korea's efforts toward carbon neutrality.

Development of monitoring system to prevent inflow of marine life into the nuclear power plant (해양생물의 원전 취수구 유입 방지를 위한 모니터링 시스템 개발)

  • Tae-Jong KANG;Eun-Bi MIN;Joong-Ro SHIN;Doo-Jin HWANG
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.60 no.3
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    • pp.277-289
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    • 2024
  • Climate change has led to a significant increase in jellyfish populations globally, causing various problems. For power plants that use nearby seawater for cooling, the intrusion of jellyfish into intake systems can block the flow, leading to reduced output or even shutdowns. This issue is compounded by other small marine organisms like shrimp and salps, making it urgent to develop solutions to prevent their intrusion. This study addressed the problem using the BioSonics DT-X 120 kHz scientific fish finder to conduct preliminary tank experiments. We also deployed underwater acoustic and camera buoys around the intake of nuclear power plant, utilizing a bidirectional communication system between sea and land to collect data. Data collection took place from July 31, 2023 to August 1, 2023. While harmful organisms such as jellyfish and salps were not detected, we successfully gathered acoustic data on small fish measuring backscattering strength (SV). Analysis showed that fish schools were more prominent in the evening than during the day. The highest fish distribution was observed at 3:30 AM on July 31 with an SV of -44.8 dB while the lowest was at 12:30 PM on the same day with an SV of -63.4 dB. Additionally, a solar-powered system was used to enable real-time data acquisition from sea buoys with smooth communication between the land server and the offshore buoy located 1.8 km away. This research developed an acoustic-based monitoring system for detecting harmful organisms around the intake and provided foundational data for preventing marine organism intrusion and planning effective measures.

Hydro-acoustic survey on fish distribution and aggregated fish at artificial reefs in marine ranching area (음향조사기법을 이용한 수산자원 관리수면의 어류분포 및 인공어초지역의 어군위집조사)

  • Kim, Hyun-Young;Hwang, Bo-Kyu;Lee, Yoo-Won;Shin, Hyeon-Ok;Kwon, Jung-No;Lee, Kyung-Hoon
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.47 no.2
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    • pp.139-145
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    • 2011
  • Hydro-acoustic survey was carried out to estimate a fish distribution at marine ranching area and aggregated fish schools at artificial reef area in Oeyeondo, Korea. The survey system was set up with DGPS system, scientific echo sounder (EK60, Simrad Co.), and ECDIS (Mecys. Co. LTD). A track survey and a random survey was respectively applied to the marine ranching area (474.4ha) and to the artificial reef area (within a radius of 300m). As the result, fish distribution and MVBS values in marine ranching area showed that created fisheries resources didn't come to be abundant yet as to appear fish distribution in all of the area. In the artificial reef area, it was, however, able to detect many fish school signals on the top of and around artificial reefs and to confirm the luring effect of artificial reefs.

Comprehensive Literature Study on Efficacy of Marine Therapeutic Resources (해양치유자원의 효능관련 기존의 연구문헌 분석)

  • Kim, Choong-Gon;Cho, Hyeon-Jin
    • Journal of The Korean Society of Integrative Medicine
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    • v.10 no.4
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    • pp.121-136
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    • 2022
  • Purpose : Marine therapy is an activity that promotes public health such as constitution improvement, immunity improvement, and anti-aging by utilizing marine therapeutic resources such as seawater, mud, seaweed, salt and sea climate. In Europe developed countries, the marine therapy industry has been developing for centuries, with France, Germany, and Israel leading the way. Currently, it has achieved great industrial achievements and is of great help in improving the human health. The purpose of this study is to investigate how marine therapeutic resources benefit to human health, as well as how to study and utilize their efficacy. We analyzed previous research articles related to the effects of marine therapeutic resources. Methods : The study included a total of 830 published literatures in the last 20 years from the Republic of Korea and other contries. PubMed and Google Scholar were utilized to collect the foreign source while the local scientific publications were accessed through the Korean Education and research Information Service (KERIS) and Korean studies Information Service System (KISS). The keywords used to search foreign literature were "marine therapy", "Thalassotherapy", "seawater", "deep seawater", "saline groundwater", "sand therapy", "mud therapy", "hydrotherapy", "seaweed", "Sun light", "sea salt", "marine animal", and "marine microorganisms" were combined, and for the domestic literature, the keywords were "marine therapy", "marine therapeutic resources", "seawater", and "sand". Results : A total of 830 research papers were found as a result of searching for domestic and international papers related to marine therapeutic resources. The collected documents were classified into 175 seawater resources, 259 marine mineral resources, 41 marine environment, and 355 marine organisms. The efficacy of each marine therapeutic resources was analyzed. By resources type, there were about 213 papers on the efficacy of seaweed, followed by about 175 papers on seawater, 142 on microorganisms, 124 on mud/peat, and sand, salt, minerals and others are appeared in order (Table 1). Conclusion : Korea has the highest marine biodiversity index, excellent tidal flats, four distinct seasons, and various sea environments of the East sea, Yellow sea, South sea and Jeju sea. For this reason, Korea has a much more diverse marine therapeutic resources than other advanced countries in the marine therapy industry. prebiously, we thought that the sea was only valuable as a shipping port and fishery industry. But now, it been shown that the ocean can become a new industrial field which can contribute to human health and well-being by providing healing and therapy to people through the gift of marine resources.

Current Status and Evaluation of Fisheries By-products: Major Options to Marine Bioindustrial Application (수산부산물의 발생·이용 실태 평가 및 해양바이오 산업화 방안)

  • Ahn, Soeon;Lee, Won-Kyu;Jang, Duckhee;Kang, Do-Hyung
    • Ocean and Polar Research
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    • v.43 no.3
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    • pp.149-164
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    • 2021
  • Since the existing mass production and consumption systems are no longer sustainable, countries are pushing for policies to make fisheries by-products as resources in an eco-friendly manner, and international standards are also being strengthened to increase the value of by-products. In Korea, economic and environmental perceptions of the by-products are rapidly changing, such as realizing carbon neutrality and enhancing circular resources by Korean Sustainable Development Goals. Raw materials derived from the by-products have been steadily imported from 2018. In particular, the number of imports of fish collagen peptides was only 16 number of times in 2017, but was rapidly increased to 483 number of times in 2020. Simultaneously, the demand for raw materials and nutrients for health functional food derived from fish by-products, which did not exist statistically until 2017, started to arise from 2018, and in 2019, consumption of high-value-added raw materials for fish by-products increased by 45% compared to the previous year. However, limitations are in legal and biotechnical industry aspects while its value as a biomaterial is recognized in the by-products-related industry. In this study, therefore, the status of by-products for upcycling biomaterials was reported and provided a scientific basis for supporting governmental strategies. In order to fulfill with the principles of a sustainable circular economy, the factors on hinder the marine bio-industrialization of the by-products were derived and suggested directions and plans for development into a high-value added the by-products as the marine bio-industry by substituting imported raw materials to support the development.

Fish Reproduction Potential Indices in the Coastal and Offshore Ecosystems in Korea (한국 연근해 생태계의 잠재 재생산 지수)

  • Lee, Sun-Kil;Lee, Jae-Bong;Zhang, Chang-Ik;Lee, Dong-Woo
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.40 no.1
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    • pp.24-30
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    • 2007
  • We developed an ecosystem indicator (EI) for the coastal and offshore areas of Korean waters. One of the major scientific challenges of this undertaking was to translate broad policy statements for ecosystem-based fisheries management (EBFM) into practical terms. Fish reproduction potential (FRP) was defined as an EI to describe the reproductive probability of adult fisheries resources in Korean waters. The FRP was estimated as the ratio of adult fish composition to total catch, catches (in metric tons) by species and by ecosystem, and fishery effort (in horse power per metric ton). The FRP indices of the East/japan Sea Ecosystem (EJSE), Yellow Sea Ecosystem (YSE), and East China Sea Ecosystem (ECSE) began to decrease after the mid-1980s, and the current indices have decreased further, at 0.63 (EJSE), 1.22 (YSE), and 0.68 (ECSE) index points compared to the indices of 1975, when similar catch amounts were recorded. Lower FRPs in the Korean marine ecosystems were the result of higher proportion of immature fisheries resources in the total catch. Because this kind of ecosystem-level indicator is thought to reflect scientific approaches to EBFM and to provide an important tool for assessing the current status of marine ecosystems with respect to both quantity and quality, more EIs should be developed for Korean waters.

Functions and values of sulfated polysaccharides from seaweed

  • D. P. Nagahawatta;N. M. Liyanage;Thilina U. Jayawardena;Fengqi Yang;H. H. A. C. K. Jayawardena;M. J. M. S. Kurera;Fahe Wang;Xiaoting Fu;You-Jin Jeon
    • ALGAE
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    • v.38 no.4
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    • pp.217-240
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    • 2023
  • Sulfated polysaccharides (SPs) isolated from seaweed have emerged as remarkable bioactive compounds with a wide spectrum of biological activities and have substantial value in the scientific and industrial domains. The current study explores the diverse biological activities of SPs and their relationship with their structures. This aids in an in-depth examination of the multifaceted biological activities of SPs, including anticoagulant, anti-inflammatory, antiviral, antioxidant, and immunomodulatory properties, which underpin their potential health benefits. Furthermore, the current study explores the complicated properties of SPs, with their extraction methodologies and techniques for precise characterization. Elucidation of the commercial significance of SPs derived from brown, red, and green seaweed by highlighting their potential applications has emphasized their importance in human well-being. Further, this review emphasizes the challenges needed to overcome research and industrial innovations for SPs. Collaboration among researchers, industry stakeholders, and regulatory authorities can overcome these challenges and elevate the potential of SPs to revolutionize industries such as pharmaceuticals, cosmeceuticals, food, and biotechnology.

Sustainability Evaluation for Shellfish Production in Gamak Bay Based on the Systems Ecology 2. Environmental Accounting for the Improvement of the Natural Environment Based on the Emergy Evaluation (시스템 생태학적 접근법에 의한 가막만 패류생산의 지속성평가 2. 가막만 환경개선에 관한 환경회계)

  • Oh, Hyun-Taik;Lee, Suk-MO;Lee, Won-Chan;Jung, Rae-Hong;Hong, Suk-Jin;Kim, Nam-Kook;Tilburg, Charles
    • Journal of Environmental Science International
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    • v.17 no.8
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    • pp.857-869
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    • 2008
  • The objective of this research is to apply more scientific, quantitative methods and procedures of environmental investigation to the development of the natural environment and the improvement of the human environment during the establishment of a sewage treatment plant and special facilities using environmental accounting. This research was performed to develop a method of strategic environmental assessment on the operation of sewage treatment plant and reuse of shellfish seeding areas through the use of environmental accounting based on EMERGY evaluation. The result was applied to marine environment policy in order to evaluate the real wealth of the regional environment and economy for both the present phase and the proposed developed phase. Using results from the comparison of EMERGY indices between the present situation and future scenarios, cost benefit analysis was performed for three different scenarios: (I) construction of a new sewage treatment plant, (2) relocation and recovery of the shellfish seeding area, and (3) relocation and re-seeding of shellfish area and construction of a new sewage treatment plant. Cost-benefit ratios of the three scenarios are 1.88, 0.94, and 1.38, respectively.