• Title/Summary/Keyword: Ocean resource

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Effects of Seed Preservation Periods and Soil Composition on the Seed Germination and Seedling Growth of Halophyte Suaeda japonica (염생식물 칠면초(Suaeda japonica)의 종자발아와 유묘생장에 종자 보관기간과 토양구성이 미치는 영향 )

  • Yong Sung, Kwak;Si Eun, Kim;Ji Chul, Oh;Seo Kyoung, Park;Han Gil, Choi
    • Ocean and Polar Research
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    • v.44 no.4
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    • pp.311-317
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    • 2022
  • Seed germination and seedling growth of a halophyte, Suaeda japonica were examined to measure the effects of seed preservation periods and various soil compositions in the mudflat of Saemangeum, Korea. Seed germination declined from 74.30% to 44.30% as the preservation period increased from 4 months to 12 months. After 14 days of seeding, seed germination was lowest in sandy soil (SS) at 8.67% and highest in earthworm cast+leaf mold (EC+LM) at 67.33%, showing 4~5 times higher than SS. The average lengths of seedlings were 12.20 mm in SS and 42.20 mm in EC+LM, respectively. These results suggest that seed germination and seedling growth enhanced in the soil that has more organic matter. In the experiment mixing Saemangeum soil (SMS), seed germination was from 4.00% in SMS to 88.00% in the soil of SMS+EC+LM after 14 days. Similar growth patterns were observed in the length of seedlings from 5.00 mm in SMS to 49.60 mm in SMS+EC+LM. The present results indicate that a population of Suaeda japonica could be established by stimulating seed germination and seedling growth by the addition of organic matters such as EC, LM, and EC+LM in the Saemangeum mud flat.

A Study on Construction of Aids to Navigation Big Data Based on S-201

  • Kim, Yunjee;Oh, Se-woong;Jeon, Minsu
    • Journal of Navigation and Port Research
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    • v.46 no.5
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    • pp.409-417
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    • 2022
  • The International Association of Lighthouse Authorities (IALA) utilizes a questionnaire to investigate the status of Aids to Navigation (AtoN) around the world. However, results of the IALA questionnaire have limited use because respondent understanding is inconsistent. In addition, there is uncertainty regarding the appropriateness of the questionnaire content. Furthermore, the overall response rate is low. Therefore, the status of AtoN is not clearly understood. AtoN data from around the world are generated hourly. Thus, big data solutions are required to effectively exploit the information. Digitization of analog data is an important component of building big data. Hence, the IALA has developed a Maritime Resource Name (MRN) scheme and an information exchange standard. Here, we used the AtoN information exchange standard and designed an S-201-based big data construction process that could collect and manage global AtoN information. In this study, construction of an IALA AtoN portal was proposed as the core of the construction of the AtoN big data. The process was divided into three stages. IALA AtoN portal is developed by IALA with the goal to provide various meaningful statistical analysis results based on AtoN data while managing AtoN information around the world based on S-201. If an AtoN portal capable of constructing S-201-based big data is developed, then a data collection and storage system that can gather basic S-201 AtoN data from the IALA and global AtoN management agencies could be achieved. Furthermore, insightful statistical analysis of AtoN status worldwide and changes in manufacturing technology will be possible.

Optimal Processing for Peptic Hydrolysate from Flounder Skin and Its Skincare Function (광어껍질을 활용한 펩신가수분해물 제조공정 최적화와 피부건강 기능성)

  • Kang, You-an;Jin, Sang-Keun;Ko, Jonghyun;Choi, Yeung Joon
    • Journal of Marine Bioscience and Biotechnology
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    • v.14 no.1
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    • pp.9-24
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    • 2022
  • Low-molecular weight peptides derived from fish collagen exhibit several bioactivities, including antioxidant, antiwrinkle, antimicrobial, antidiabetic, and antihypertension effects. These peptides are also involved in triglyceride suppression and memory improvement. This study aimed to investigate the optimal processing condition for preparing low-molecular weight peptides from flounder skin, and the properties of the hydrolysate. The optimal processing conditions for peptic hydrolysis were as follows: a ratio of pepsin to dried skin powder of 2% (w/w), pH of 2.0, and a temperature of 50℃. Peptic hydrolysate contains several low-molecular weight peptides below 300 Da. Gly-Pro-Hyp(GPHyp) peptide, a process control index, was detected only in peptic hydrolysate on matrix-assisted laser desorption/ionization-time-of-flight(MALDI-TOF) spectrum. 2,2'-azinobis-(3-3-ethylbenzothiazolline-6- sulfonic acid(ABTS) radical scavenging activity of the peptic hydrolysate was comparable to that of 1 mM ascorbic acid, which was used as a positive control at pH 5.5, whereas collagenase inhibition was five times higher with the peptic hydrolysate than with 1 mM ascorbic acid at pH 7.5. However, the tyrosinase inhibition ability of the peptic hydrolysate was lower than that of arbutin, which was used as a positive control. The antibacterial effect of the peptic hydrolysate against Propionibacterium acne was not observed. These results suggest that the peptic hydrolysate derived from a flounder skin is a promising antiwrinkle agent that can be used in various food and cosmetic products to prevent wrinkles caused by ultraviolet radiations.

A study on the mesh size selectivity by alternate haul method of trawl using the SELECT model (SELECT 모델을 이용한 트롤 비교 시험조업법에 의한 망목 선택성에 관한 연구)

  • Seonghun KIM;Hyungseok KIM;Sena BAEK;Jaehyung KIM;Pyungkwan KIM
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.59 no.2
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    • pp.99-109
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    • 2023
  • In this study, a comparative test operation was conducted through the alternate haul method to examine the selectivity of the four mesh sizes (60 mm, 90 mm, 110 mm, and 130 mm) of the trawl codend. The selectivity was analyzed using the SELECT model considering the fishing efficiency (split parameter) of each fishing gear in the comparative test fishing operation in the trawl and the maximum likelihood method for parameter estimation. A selectivity master curve was estimated for several mesh sizes using the extended-SELECT model. As a result of analyzing the selectivity for silver croaker based on the results of three times hauls for each experimental gear, it was found that the size of the fish caught increased as the size of the mesh size increased. When the selectivity for each mesh size analyzed by the SELECT model considering the split ratio was evaluated based on the size of the AIC value, the estimated split model was superior to the equal split model. Based on the master curve, the 50% selection length value was 2.893, which was estimated to be 136 mm based on the mesh size of 60 mm. In some selectivity models, there was a large deviance between observed and theoretical values due to the non-uniformity of the distribution of fished length classes. As a result, it is considered that appropriate sea trials and selectivity evaluation methods with high reliability should be applied to present trawl fishery resource management methods.

Stability of hair-tail angling fishing boat according to the induction fishing lamp installation (인덕션 집어등을 설치한 갈치채낚기 어선의 복원성능)

  • Seongjae JEONG;Seongwook PARK;Myongkok JEONG;Geumcheol JEONG
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.59 no.1
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    • pp.1-8
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    • 2023
  • In this study, the stability of fishing boat inducing the change of fishing lamp in accordance with the installation of induction lamp in comparison with metal halide lamp was investigated. Inclining test for 8.55 ton class of hair-tail angling fishing boat was performed in order to find a GM and light weight. A stability calculation of the target fishing boat on the basis of KST-SHIP program was evaluated. The stability of the fishing boat with a metal halide lamp such as induction lamp according to the result obtained by the inclining test is slightly different, and the stability is not so much affected. Due to the induction lamp installation, the wind area increased by about 3.178 m2. Before installing the induction fishing lamp, G0M was found to be 0.209 at full load departure and 0.296 at departure from fishing ground. After installing the induction lamp, the full load departure condition is 0.178 and the fishing ground departure condition is 0.260. The G0M value before and after installation of the induction fishing lamp shows a difference of about 3% at the full load departure condition. The value of the critical angle of inclination definition showed a difference of about 16%. Despite these differences, it is lower than the regulations; it was confirmed that there will be no significant difference unless it is in an overloaded state.

Optimized design and verification of Ship-type Floating Lidar Buoy system for Wind resource measurement in the Korean West Sea (서해안 해상풍력단지 풍황관측용 부유식 라이다 운영을 위한 선박형 부표식 최적화 설계 및 검증)

  • Yong-soo Gang;Jong-kyu Kim;Baek-beom Lee;Su-in Yang;Jong-wook Kim
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • 2022.06a
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    • pp.161-164
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    • 2022
  • 부유식 라이다는 해상풍력단지 조성시 필수적으로 수행하고 있는 풍황관측 업무에 새로운 패러다임을 제공하고 있는 시스템으로, 전통적으로 풍황관측을 수행하고 있던 해상기상관측탑을 대체하여 사업 초기의 대규모 공사를 획기적으로 축소하여 시간과 비용을 절약하고, 환경적 영향을 최소화 하며, 지역사회의 반발 요소까지 줄일 수 있어 해당 업계의 표준으로 자리잡고 있는 중이다. 다만 부표식의 동요에 따른 외란적 요소가 관측자료의 신뢰성에 영향을 미치는 만큼 안정적인 플랫폼의 설계 및 검증이 매우 중요한 상황이며, 국내에서는 해당기술에 대한 늦은 진입으로 인해 다수의 외산장비 제조사들이 국내시장까지 선점하고 있는 상황이다. 한국의 서해안은 천해 환경으로 조석차가 매우 커 지역에 따라 강한 조류가 반복적으로 나타나며, 계절별로 상이한 강한 에너지의 파랑이 형성되는 등 플랫폼에 안정도에 많은 영향을 미치는 바다 환경을 갖고 있다. 본 논문에서는 이러한 복잡한 환경적 특성을 갖고 있는 우리나라의 해역에 라이다 운영에 적합한 부표식에 대한 연구를 수행하며, 우선적으로 적용하였던 선박형 부표식의 최적화 설계 및 검증 사례를 소개하고, 향후 다양한 플랫폼 개발에 토대가 되는 중요 개념을 도출하고자 한다.

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Unrecorded species of Korean invertebrates discovered through the project of 'Discovery of Korean Indigenous Species' III

  • Su-Jung Ji;Jongwoo Jung;Sa Heung Kim;Dong-Ha Ahn;Min-Seop Kim;Jeounghee Lee;Hee-Min Yang;Geon Hyuk Lee;Eunjung Nam;Taeseo Park;Anna B. Jost;Huyen T. M. Pham;Jina Park;Joohee Park;Seoyoung Keum;Ivana Karanovic;Tomislav Karanovic;Joong-Ki Park;Chuleui Jung;Gi-Sik Min
    • Journal of Species Research
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    • v.12 no.4
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    • pp.341-354
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    • 2023
  • This is the third series of catalogs reporting on Korean species discovered through the 'Discovery of Korean Indigenous Species'. This catalog includes 22 species of invertebrates, excluding insects. The catalog includes the scientific name, an abridged list of synonyms, collection sites, distribution, diagnosis, and figures for each species. Additionally, we provide the newly assigned Korean name, specimen voucher, and, if available, mitochondrial CO1 or 16S gene sequences of the species listed. All species identified and documented here will be officially listed on the 'National Species List of Korea', a database maintained by the National Institute of Biological Resources(NIBR).

Bycatch reduction plan of offshore dredge in the western sea, Korea (서해안 근해형망 어업의 혼획저감 방안)

  • Sug-Tai KIM;Hyun-Young KIM
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.59 no.4
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    • pp.290-300
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    • 2023
  • This study aimed to identify the actual catch situation of offshore dredge gear which is newly regulated in the legislation. It's also conducted to identify the species composition, weight of the catch including the target species and incidental catches, and to provide the basic information necessary for the resource management of aquatic organisms caught by offshore dredge. During the investigation period (from September 2022 to May 2023), a total of 61 species appeared in the test operation sea of Boryeong, Chungcheongnam-do and Gunsan, Jeollabuk-do, with 31 species of fishes, 11 species of malacostraca, six species of gastropoda, five species of bivalvia, three species of cephalopoda, three species of asteroidea, one species each of asteroidea and holothuroidea appeared. According to the results of the test operation conducted in September and November 2022, the non-catch season of Atrina (Servatrina) pectinata, 1,203 shellfishes were caught out of 2,979 caught in number, showing a bycatch rate of 59.6%, and by weight, 157.9 kg of shellfish was caught out of the total catch of 448.4 kg, showing a bycatch rate of 64.8%. On the other hand, in February and May 2023, the catch season for Atrina (Servatrina) pectinata, 3,692 fishsells were caught out of the 4,232 catches in total, showing a bycatch rate of 12.8%, and by weight, 1,185.0 kg of shellfish was caught out of the total catch of 1,293.2 kg, showing an 8.3% bycatch rate.

A revised ecosystem-based fishery risk assessment incorporating IUU fishing (IUU어업을 고려한 생태계기반 자원평가)

  • Youjung KWON;Sung Il LEE;Chang Ik ZHANG
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.60 no.3
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    • pp.244-257
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    • 2024
  • Considering the negative impact of IUU fishing on fishery resources and fishery management, a revised approach for estimating risks of the ecosystem-based fisheries assessment (EBFA) of Zhang et al. (2011) was developed that incorporates three components of the IUU (illegal, unreported and unregulated) fishing as penalties. In this study, we introduced ways to develop indicators of IUU fishing suitable for the Korean fishery and apply them to ecosystem-based resource assessment. The indicator for the illegal fishing component was set as the fishing without licenses or permits, and that for the unreported fishing component was set as unreported fishing activities. Indicators for the unregulated fishing component were set as fishing operated by illegal fishing gear, illegal fish capture, fishing operations in prohibited fishing area, and fishing with restrict permits. IUU fishing significantly impacts the stock of target species. Therefore, in this study, the influence of IUU fishing is included in the Species Risk Index (SRI) at the species level, and weights are assigned based on the ratio of the stock, as $SRI={{\sum\limits_j}{\lambda}_j{\cdot}ORI/{\sum\limits_j}{\lambda}_j}+P_f(B_i/B)$. The revised ecosystem-based fisheries assessment method, which considers the impact of IUU fishing, was applied to major fisheries on the south coast of Korea. It is necessary to reduce the non-reporting rate through the expansion of the TAC system and improve the accuracy of statistical compilation. To this end, the electronic fishing reporting system, which is being implemented on all vessels in Korean distant water fishing vessels, should be introduced to the coastal and offshore fisheries as well.

Analysis of Appropriate Automobile Tax Rate Considering the Average CO2 Emissions by Engine Displacement in Korea (한국의 배기량별 평균 CO2 배출량을 고려한 자동차세의 적정 세율 분석)

  • Hyunwoo Choi;Min Gyeong Jung;Hyeon Woo Jang;Dong Koo Kim
    • Environmental and Resource Economics Review
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    • v.32 no.4
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    • pp.217-238
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    • 2023
  • Currently, automobile tax in Korea is imposed by multiplying the vehicle's engine displacement by a certain tax rate. However, the need for revision is being raised as it is pointed out that the current system does not reflect the immediate task of reducing greenhouse gas emissions. Accordingly, this study focuses on the positive relationship between engine displacement and CO2 emissions, and seeks to calculate an appropriate automobile tax rate considering average CO2 emissions. To this end, first, we estimated the average annual CO2 emissions (kg/vehicle) for each engine displacement using the average CO2 emissions for each vehicle displacement as of 2020. Next, multiple scenarios were analyzed considering the standard tax rate at $75 per ton of CO2 emissions proposed by the IMF (2019). In particular, we compared the case of imposing a uniform carbon tax of $75 and the case of imposing a progressive tax based on CO2 emissions by displacement. According to the results, it was confirmed that the uniform tax rate proposed by the IMF is difficult to apply to Korea as it is due to the impact of a decrease in tax revenue, and a tax scheme needs to be designed appropriately considering maintenance of tax revenue according to the current automobile tax, greenhouse gas reduction effect, and automobile tax reform trends in developed countries. For example, in the case of the K3 (1,598cc) of Kia Motors, a representative compact car sold in Korea, if we compare the tax burdens for each tax scenario, the tax burden will be about 220,000 KRW under the current system, about 79,000 KRW under the uniform tax rate, about 83,000 KRW under the progressive tax rate, and about 240,000 KRW under the progressive tax rate similar to the UK tax system, respectively. In this way, this study identified the current statuses of automobile registration and tax in Korea, and automobile tax reform trends in major developed countries, and analyzed the impact of automobile tax reform considering engine displacement and CO2 emissions, focusing on the tax burden of the people.