• Korean Journal of Environmental Biology
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• v.42 no.1
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• pp.127-134
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• 2024

The feathery branched green alga Bryopsis plumosa (Hudson) C. Agardh bloomed at Songji Beach, Haenam, Korea, in November 2022. A terrible stench was present on the beach, and the bottom was covered in a thick green mat of green algae. The alga was identified as B. plumosa, which is an opportunistic species currently distributed worldwide. Dissolved inorganic nitrogen (DIN) and dissolved inorganic phosphorus (DIP) were analyzed in the bloomed area and compared with those of other vicinities. The DIN and DIP concentrations were 1.067 and 0.461 mg L^-1, respectively, which were 6 to 19 times higher than the average concentrations on southwest coasts, including Haenam. The B. plumosa bloom at Songji Beach in November 2022 appears to have depended on DIN and DIP concentrations in seawater. In this study, we report on the mass occurrence of B. plumosa, which appeared for the first time in Korea. This occurrence was found to be closely related to the concentration of nutrients in seawater. Therefore, it is necessary to manage the concentration of nutrients on land flowing into coastal waters to control green algal blooms such as Bryopsis.

• Journal of Korea Port Economic Association
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• v.40 no.2
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• pp.53-64
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• 2024

ESG management has garnered significant recognition as a crucial concern across all global industries. Within the logistics sector, there is a growing awareness of the importance of ESG management. However, active engagement in ESG practices remains predominantly confined to large corporations, leaving small and medium-sized logistics companies lagging in their comprehension and implementation of ESG principles. Previous studies have consistently underscored the necessity of establishing ESG management guidelines. Furthermore, there has been a call to determine the relative weights assigned to various ESG implementation evaluation criteria, taking into account the distinctive attributes of each category of logistics company. This study endeavors to ascertain the weightings of ESG implementation evaluation items for different types of logistics companies by employing the Analytic Hierarchy Process (AHP) methodology. The framework of evaluation is based on the evaluation items outlined in prior research, particularly focusing on ESG management guidelines tailored for small and medium-sized logistics companies. The findings of the analysis reveal distinct prioritizations across different sectors within the logistics industry. For maritime logistics companies, the environment emerges as the foremost concern, followed by society, information disclosure, and governance. Conversely, land transportation companies prioritize society, followed by governance, environment, and information disclosure. In the warehousing sector, environment takes precedence, followed by society, information disclosure, and governance. Comprehensive logistics firms, on the other hand, prioritize the environment, followed by information disclosure, society, and governance. Such guidelines are pertinent for regulatory bodies and industry stakeholders seeking to assess ESG practices within these enterprises. Moreover, this research contributes to the body of knowledge available to domestic small and medium-sized logistics companies, aiding them in effectively navigating and implementing ESG management principles.

• Journal of the Korean Geotechnical Society
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• v.40 no.4
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• pp.33-47
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• 2024

Offshore wind structures are subject to long-term repeated horizontal loads from wind, waves, and currents, making it essential to consider these loads in the design of offshore foundations. In this respect, monopiles are large-diameter hollow steel pipes that are relatively simple to construct compared with piles used on onshore sites. They can provide stable support for wind structures and have well-established design codes, leading to their widespread use globally. The behavior of monopiles under lateral static loads is typically assessed using the p-y method proposed by the American Petroleum Institute (API). However, the applicability of p-y curves to large-diameter monopiles exposed to repeated cyclic horizontal loads, such as those experienced in offshore wind applications, must yet be evaluated. Thus, this study evaluated the behavior of monopiles under two-way cyclic horizontal loads in loose silty sand, a representative soil type of the southwestern coast of Korea, using centrifuge model tests. The results demostrated that the behavior of monopiles varied depending on the loading level, number of cycles, and direction of the cyclic loads. Furthermore, the p-y curve method proposed by the API overestimated the behavior of a large-diameter monopile installed in silty sand under two-way cyclic loads.

• Economic and Environmental Geology
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• v.57 no.4
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• pp.387-396
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• 2024

The geological disposal of high-level radioactive waste (HLW) involves permanently isolating the wastes in stable geological formations deep underground. Mudstone (siltstone and claystone) containing abundant clay minerals is proposed as a host rock for geological disposal of HLW because clay minerals have low permeability and high ion sorption/exchange capacity. Despite the widespread occurrence of sedimentary basins in Korea, there is a lack of evaluation of mudstone as host rocks for geological disposal. In this study, we utilized the JBH-1 borehole (7-754 m) obtained from the Jinju Formation to investigate the distribution trend and mineral compositions of mudstone. Additionally, we conducted comparative analyses with the Opalinus Clay in Switzerland considered as host rock of geological disposal of HLW. Claystone containing more than 40% clay minerals exhibit thick layers primarily in the upper section (7-350 m) of the JBH-1 borehole. While the clay minerals content of claystone does not show significant variation with depth, there are differences in the characteristics of feldspar and carbonate minerals. These mineralogical variations can led change in pore water chemistry and rock mechanical properties. The clay minerals content of claystone in the Jinju Formation is similar to that of the Opalinus Clay. However, there are notable differences in clay minerals composition. While the Opalinus Clay contains smectite-illite mixed-layer minerals, the Jinju Formation are dominated by illite indicating higher burial temperatures. This information will be useful for studying the host rock of HLW geological disposal site in Korea.

• Journal of Navigation and Port Research
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• v.48 no.4
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• pp.335-341
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• 2024

Recently, research, development, and commercialization of maritime autonomous surface ships (MASS) and remote control are in progress. Remote control is intended to secure autonomous navigation environments for existing ships or early-stage MASS using a remote control system (RCS). The main function of an RCS is to control MASS using data transmission between the MASS and the remote control centre. Remote control by a remote control officer also has an important function. The purpose of this study was to develop RCS and a performance evaluation technique for operation data provided by the RCS. The experiment was conducted during the navigation period of a training ship 'Hannara' after building experimental equipment at both an onshore remote control center and a training ship. As a result of evaluating data transmitted and received using the developed RCS, it was confirmed that data transmission was possible within an error range of 0.1%p. Fourteen types of ship information reflecting the navigation environment of the training ship were confirmed to be transmitted and received. The RCS developed in this work complies with the three principles of remote control: safety, reliability, and availability. This study provides a core technology for the development of RCSs for MASS and the evaluation of data transmission performance.

• Microbiology and Biotechnology Letters
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• v.52 no.3
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• pp.304-313
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• 2024

In this study, the microbial distribution and diversity of kimchi manufactured in the same method as salted cabbage manufactured from Pyeongchang, Andong, and Haenam cabbage according to the storage period were compared. Among Pyeongchang, Andong, and Haenam salted cabbages, the Haenam salted cabbage microbial community showed the highest diversity on the 1st day of storage. As the storage period of salted cabbage increased, the alpha diversity value increased, the proportion of cyanobacteria decreased, and bacteria derived from sea salt and water increased. Principal coordinates analysis(PCoA) and unweighted pair group method with arithmetic mean(UPGMA) trees showed that Andong salted cabbage on the 5th day of storage had a microbial community close to salted cabbage on the 10th day of storage. At the species level, Sinocapsa zengkensis was 78.65%, 90.64%, and 63.44%, respectively, in Pyeongchang, Andong, and Haenam salted cabbages on the 1st day of storage. Marinomonas primoryensis was showed in Pyeongchang, Andong, and Haenam salted cabbage on the 5th day of storage at 24.39%, 26.60%, and 21.75%, respectively, and at 42.17%, 31.43%, and 45.21%, respectively, on the 10th day of storage. Kimchi made from Pyeongchang, Andong, and Haenam salted cabbages showed Janthinobacterium lividum at 30.47%, 29.60%, and 25.97%, respectively. In addition, Leuconostoc spp. involved in fermentation were showed from the 5th day of storage, but Andong salted cabbage on the 10th day of storage was not showed. These results show to be due to differences in soil, climate, and cultivation methods of cabbage.

• Korean Journal of Soil Science and Fertilizer
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• v.1 no.1
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• pp.89-115
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• 1968

1. The experiment was carried out for investigating the interaction between potassium nutrition and thermoperiod (as an environment regulating factor) in relation to behaviors of several nutrients including phosphorus-32 and Potassium-42 in IPOMOEA BATAS. 2. To obtain same condition to trace the behaviors of phosphorus and potassum-42 they were simultaneously incorporated to roots. The determination of each CPM by counting twice with adequate interval and calculating true CPM of each isotope according to different half-life, was carried out with satisfactory. 3. Some specific symptoms i.e, chlorosis and withering of growing point under the condition of lower potassium level were found and was accelerated by the low night temperature. 4. A manganese shortage in growing point of the lower potassium level was found by activiation analysis and very low distribution ratio of phosphorus-32 and potassium-42 in the growing point of the lower potassium level was manifested, though the contents of nitrogen, phosphorus, potassium, sodium and magnesium were not in great difference. 5. In addition to the low water content with appearence of "hard", shorterning internode and lower ratio of roots to shoot as well as the symptoms of potassium deficiency such as brown spot in leaf blade and necrosis of leaf margin were appeared at later stage of experiment at the lower potassium level. 6. Very stimulating vegetative growth, e.g, large plant length, leaf expansion, increasing node number and fresh weight as well as high ratio of roots to shoot, high water content was resulted in the condition of higher potassium level. 7. A specific interaction between higher potassium level and thermoperiod was found, that is, the largest tuber production and the largest ratio of roots to shoot were resulted in the combined condition of higher potassium level and constant temperature while the largest plant length, fresh weight etc. i.e. the most stimulative vegetative growth was resulted in the combined condition of higher potassium level and low night temperature. 8. Comparatively low water content in the former condition of stimulative tuber production was resulted(especially at the tuber thickening stage), while high water content in the latter condition of stimulative vegetation was resulted though the higher potassium level made generally high water contents. 9. The nitrogen contents of soluble and insoluble did not make distinct difference between the lower and higher potassium level. 10. Though the phosphorus contents were not distinctly different by the potassium level, the lower potassium level made the percentage of phosphorus increased at tuber forming stage accumulating more phosphorus in roots, while the higher potassium level decreased percentage of phosphorus at that stage. 11. The higher potassium level made distinctly high potassium contents than the lower potassium level and increased contents at the tuber forming stage through both conditions. 12. The sodium contents were low in the condition of higher potassium level than the lower potassium level and decreased at tuber forming stage in both conditions, on the contary of potassium. 13. Except the noticeable deficeney of manganese in the growing point of the lower potassium level, mangense and magnesium contents in other organs did not make distinct difference according to the potassium level. 14. Generally more uptake and large absorption rate of phosphorus-32 and potassium-42 were resulted at the higher potassium level, and the most uptake, and the largest absorption rate of phosphorus and potassium-42 (especially potassium-42 at tuber forming stage) were resulted in the condition of higher potassium level and constant temperature which made the highest tuber production. 15. The higher potassium level stimulated the translocation of phoshorus-32 and potassium-42 from roots to shoots while the lower potassium level suppressed or blocked the translocation. 16. Therefore, very large distribution rate of $p^{32}$, $K^{42}$ in shoot, especially, in growing point, compared with roots was resulted in the higher potassium level. 17. The lower potassium level suppressed the translocation of phosporus-32 from roots to shoot more than that of potassium-42. 18. The uptake of potassium-42 and translocation in IPOMOEA BATATAS were more vivid than phosphorus-32. 19. A specific interaction between potassium nutrition and thermoperiod which resulted the largest tuber production etc. was discussed in relation to behaviors of minerals and potasium-42 etc. 20. Also, the specific effect of the lower and higher potassium level on the growth pattern of IPOMOEA BATATAS were discussed in relation to behaviors of minerals and isotopes. 21. An emphasize on the significance of the higher potassium level as well as the interaction with the regulating factor and problem of potassium level (gradient) for crops product ion were discussed from the point of dynamical and variable function of potassium.

• Journal of Physiology & Pathology in Korean Medicine
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• v.16 no.1
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• pp.32-44
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• 2002

Gu-Chang is a disorder characterized by recurring ulcers confined to the oral mucosa. Despite much clinical and research attention, the causes remain poorly understood. In this paper, we will compare Gu-Chang with Recurrent Aphthous Stomatitis(RAS) in order to know what is the similiarity between Gu-Chang and RAS. So we will arrange various oriental and western medical literatures which are important. As a result of arrangement of the causes, symptoms and therapys of Gu-Chang, we can conclude through the studies as follows. 1. The etiologies of Gu-chang are following. In the Sthenia syndrome, there are evil heat of external factor, heat of heart and spleen, insomnia, heat of upper warmer, stress and diet, heat of lung and heart, excessive heat of upper warmer, inappropriate food intake, heat conveyance of organ, heat of stomach merdian, moistured heat of spleen and stomach and stasis of liver energy. In the Asthenia syndrome, there are deficiency of stomach energy, deficiency of upper warmer leading to heat, deficiency of middle warmer leading to cold, deficiency of lower warmer leading to heat, deficiency of middle energy, deficiency of blood, decreased fire and deficiency of soil, yin fire of lower warmer, deficiency of heart yin, deficiency of spleen yin and deficiency of qi and blood. 2. In western medicine the causes of RAS is presumed as local, microbial, systemic, nutritional, genetic, immunologic factors. 3. Once Gu-chang is compared with RAS, in the deficiency of yin leading to hyperactivity of fire, deficiency of yin leading to floating of fire and stasis of liver energy, recurring of Gu-chang is similar to RAS. Although recurring of Gu-chang due to tripple warmer of excessive fire has no recurrance, since there are the degree of Pain, site of lesion, dysphagia etc, it is similar to major RAS. It is may be believed that Sthenia Gu-chang is similar to major RAS, shape of recurring, site of lesion, degrree of Pain and white color of Asthenia Gu-chang are similar to minor RAS, but there is no similarity concerning herpes RAS in the literatures that describe the symptoms. 4. Generally, the treatment of Gu-chang is divided into Asthenia and Sthenia Syndrome. The method of cure to Sthenia syndrome is heat cleaning and purge fire, Asthenia syndrome is nourish yin to lower and adverse rising energy and strength the middle warmer and benefit vital energy. 5. Following is the medication for Sthenia syndrome. Heat of heart and spleen is Do Jok San, Yang Gyek San, Juk Yup Suk Go Tang, evil heat of external factor is Yang Gyek San Ga Gam, Stasis of liver energy is Chong Wi Fae Dok Yum, moistured heat of spleen and stomach is Chong Gi Sam Syep Tang. The medication for Asthenia Syndrome is following. Deficiency of upper warmer leading to heat is Bo Jung Ik Gi Tang, deficiency of middle warmer leading to cold is Bu Ja Lee Jung Tang, deficiency of lower warmer leading to heat is Yuk Mi Ji Hwang Tang, deficiency of yin leading to hyperactivity of fire is Ji Baek Ji Hwang Hwan, deficiency of yin leading to floating of fire is Lee Jung Tang Ga Bu Ja Medicine for external use were Yang Suk San, Boo Wyen San, Rok Po San, Yoo Hwa San ate. 6. In western medicine, there is no specific treatment for RAS, and management strategies depend on dinical presentation and symptoms and includes antibiotics, oral rinses, glucocorticoids, immunomodulatory drugs, vitamines, analgesics, laser and antiviral agents.

• Journal of Korean Society of Environmental Engineers
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• v.34 no.8
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• pp.574-582
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• 2012

This study presents the concentrations of the polycyclic aromatic hydrocarbons (PAHs) listed as priority pollutants by United States Environmental Protection Agency (US EPA), in 98 sludges from 54 industrial wastewater treatment facilities of South Korea. The mean concentrations of ${\Sigma}_{16}PAHs$ were ranged from 32.5 ${\mu}g/kg-dw$ to 1189.3 ${\mu}g/kg-dw$ by industries, and the highest content was found in the petrochemical industry, followed by chemical, clothing manufacturing and dying, pulp and papermaking, secondary wastewater treatment, and food/beverage producing industries. Comparisons to the EU and Danish standards of ${\Sigma}_{16}PAHs$ in sewage sludge for land application showed only two samples (one from petrochemical, and the other from chemical industry) exceeded the limits. ANOVA test with PAH concentrations as variables revealed no statistically significant influences by industrial types and sampling time (i.e., seasonal variations). Pearson correlations between individual PAHs showed strong relationships (r>0.7) among 4-ring PAHs. Concentrations of acenaphthylene, anthracene, fluoranthene, benzo(a)anthracene, benzo(f)fluoranthene, benzo(k)fluoranthene, benzo(a)pyrene presented strong correlations to ${\Sigma}_{16}PAHs$. Principal component analysis discriminated entire samples into three groups by two principal components (PC1 and PC2) with 70% of data variations, in which industrial types were not of importance, but a dominance of certain PAHs. Samples in group-I, which is high PC1 and low PC2, were characterized by a dominance of 2-ring PAHs, and in group-II, PC1 and PC2 showed a linear relation, was dominant 4-ring PAHs. Group-III with low PC1 and high PC2 includes 17 samples showing a noticeably high contribution of 3-ring PAHs to ${\Sigma}_{16}PAHs$. This study provides concentrations of PAHs in industrial sludges collected from a wide variety of sources (six industrial types) and two seasons of sampling events, and the comparison of ${\Sigma}_{16}PAHs$ with other studies are also discussed.

• Korean Journal of Environmental Biology
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• v.29 no.3
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• pp.162-170
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• 2011

In order to assess the inorganic and organic pollutents characteristics in marine water, we investigated COD (Chemical Oxygen Demand), Chlorophyll a and Escherichia coli during four seasons at 20 stations of Gwangyang Bay and at 23 stations of Jinhae Bay, Korea. The bay is divided into three zones in Gwangyang and four zones in Jinhae respectively, based on the pollutent levels. In Gwangyang Bay, the high concentration (mean 4.7 mg $L^{-1)$) of COD was recorded during spring season at Zone I, which can be characterized as a semi-enclosed eutrophic area (St. 1~9). Also, Chl. a concentrations were high at Zone I (mean 14.0 ${\mu}g\;L^{-1}$). The colony of E. coli were detected during summer season at Zone II, which is influenced by Seomjin River water. The E. coli may have been entered from the river water in a large pulse during rainy season. On the other hand, E. coli was kept low levels during four seasons at the Zone III, which is influenced indirectly by surface water currents from offshore of the bay. In Jinhae Bay, the high COD and Chl. a were shown during all seasons at Zone I, which is characteristed by semi-enclosed eutrophic area of Masan and Haengam bays. The Zone I also had been shown relatively high E. coli concentration in all seasons. In constrast, other three zones did not show seasonal characteristics of the E. coli concentrations. The present study suggests that E. coli concentrations can be significantly elevated in eutrophic semi-enclosed area.