• Ocean and Polar Research
• /
• v.45 no.4
• /
• pp.201-209
• /
• 2023

Melosira nummuloides (KNU-HAPCC-101), which is a biological resource for fucoxanthin extraction, was separated from single cells, and optimal growth conditions were derived according to temperature, salinity, light intensity, light emitting diode, N:P ratio of culture medium, and dilution ratio of culture medium. These parameters were assessed to ascertain the best culture conditions for the most economical and efficient indoor mass production. The specific growth rate was the highest at 25℃ in temperature, but there was no significant difference between 15℃ and 20℃. M. nummuloides died at 0 psu in salinity, and the specific growth rate was the highest at 30 psu in respect to salinity. The light intensity was similar in all experimental groups except for 5 µmol photons m^-2 s^-2. The maximum biomass and specific growth rate in the light-emitting diode experiment were revealed at the red wavelength, but the concentration of chlorophyll-a was the lowest at the red wavelength whereas the white wavelength produced the highest chlorophyll-a concentration. In the experiment according to the ratio of nitrogen and phosphorus (N:P) based on the f/2 culture medium, the growth rate was significantly higher in the 15:1 to 50:1 ratio range. The growth rate according to the dilution concentration of the f/2 culture medium was the highest in the f/2 culture medium, but did not show a significant difference from the f/4 culture medium. M. nummuloides can be mass-cultured under conditions of a temperature of 15-25℃, a salinity of 15-35 psu, light intensity of 25-150 µmol photons m^-2 s^-2, and f/4 media concentration level with an N:P ratio 15:1 or more. Based on the data of this study, it is expected that fucoxanthin can be produced in a highly efficient manner through the development of a mass culture system.

• 한국균학회소식:학술대회논문집
• /
• 2015.05a
• /
• pp.28-28
• /
• 2015

Clubroot disease caused by Plasmodiophora brassicae induces severe losses of cruciferous vegetables worldwide. To control clubroot of Chinese cabbage, many CR (clubroot resistance) F1 hybrid cultivars have been bred and released in Korea, China and Japan. In this study, we determined the race of P. brassicae 12 field isolates, which collected from 10 regions in Korea, using Williams' differential varieties including two cabbage ('Jersey Queen', 'Badger Shipper') and two rutabaga ('Laurentian', 'Whilhelmsburger'). By Williams' differential varieties, 12 clubroot pathogens were assigned into one (GN2), two (HS and YC), two (HN1 and HN2), three (DJ, KS and SS) and four (GS, GN1, JS and PC) isolates for races 1, 2, 4, 5 and 9, respectively. In addition, the degree of resistance of 45 CR cultivars that were from Korea, China and Japan was tested with the 12 isolates. The 45 CR cultivars of Chinese cabbage were differentiated into three genotypes according to their resistance responses. Even though the 12 P. brassicae isolates were same race by Williams' differential varieties, three CR genotypes showed different resistance response to the isolates. These results indicate that races of P. brassicae by Williams' differentials were not related with resistance of CR cultivars, and three CR genotypes represented qualitative resistance to the P. brassicae isolates. CR genotype I including 'CR-Cheongrok' showed resistance to GN1, GN2, JS, GS, HS, DJ and KS isolates and susceptibility to YC, PC, HN1, HN2 and SS isolates. And CR genotype II such as 'Hangkunjongbyungdaebaekchae' was resistant to GN1, GN2, JS, GS, HS, YC, PC and HN1 and susceptible to DJ, KS, SS and HN2. CR genotype III including 'Chunhajangkun' and 'Akimeki' represented resistance to 10 isolates except for SS and HN2 isolates. Based on these results, we selected 'CR-Cheongrok', 'Hangkunjongbyungdaebaekchae', and 'Chunhajangkun' as a representative cultivar of three CR genotypes and 'Norangkimjang' as a susceptible cultivar. Furthermore, we investigated the resistance of 15 lines of Chinese cabbage, which were provided by seed companies, to 11 isolates except for HN1 of P. brassicae. The results showed that three lines were susceptible to all the tested isolates, whereas five, four, and three lines represented the similar responses corresponding to the CR genotypes I, II, and III, respectively; there is no line of Chinese cabbage showing different resistance patterns compared to three CR genotypes. In particular, line 'SS001' showing resistance responses of CR genotype II was a parent of 'Saerona' that have been commercialized as a CR $F_1$ cultivar of Chinese cabbage. Together, we divided 12 isolates of P. brassicae into 4 races, designated by wild type, mutant type 1, mutant type 2, and mutant type 3. Wild type including GN1, GN2, JS, GS, and HS isolates of P. brassicae was not able to infect all the cultivars of three CR genotypes, whereas, mutant type 3 such as SS and HN2 isolates developed severe clubroot disease on all the CR genotype cultivars. To mutant type 1 including DJ and KS isolates, CR genotypes I, II and III were resistant, susceptible and resistant, respectively. In contrast, to mutant type 2 including YC, PS, and HN1 isolates, CR genotypes I, II and III showed susceptibility, resistance and resistance, respectively. Taken together, our results provide the extended knowledge of classification of P. brassicae races, which is useful information for the breeding of resistant crops, with a suggestion that 'Norangkimjang', 'CR-Cheongrok', 'Saerona' and 'Chunhajangkun' cultivars of Chinese cabbage could be used as new race differentials of P. brassicae for clubroot disease assay.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
• /
• v.16 no.2
• /
• pp.97-105
• /
• 2011

This study investigated the community structure and spatio-temporal variation of macrobenthic assemblages around Gijang Province, East Sea of Korea. Macrobenthos collected seasonally using a modified van Veen grab sampler from March to November 2006. A total of 157 macrobenthic fauna were collected. The overall average macrobenthos density were $552 \;ind/m^2$. The species number of macrobenthos was in the range from 62 in winter and spring to 122 in autumn. On the other hand, abundance fluctuated between 6,540 (in spring) and 17,920 (in autumn) inds./$18m^2$. Cluster analysis and non-metric multi-dimensional scaling (nMDS) were applied to assess the spatio-temporal fluctuation in the macrobenthic assemblages. Cluster analysis and nMDS ordination analysis based on the Bray-Curtis similarity identified 3 station groups. The group 1 (station 8~10, 12, 13, 17 and 18) was characterized by high abundance of the polychaete Lumbrineris longifolia, the bivalve Ennucula tenuis and the Amphipoda spp., with mean phi range from $6.2{\Phi}$ to $7.1{\Phi}$ (above 50m water depth). The group 2 (station 5~7, 11, 14~16) was numerically dominated by the po1ychaete Ampharete arctica and the bivalve Theorafragilis (mean phi: $6.0{\sim}7.0{\Phi}$; within 40 m water depth). Finally group 3 (station 1~4) was characterized by high density of the polychaetes Magelona japonica and Sternaspis scutata, with mean phi range from $3.5{\Phi}$ to $6.9{\Phi}$ (below 30 m water depth). In conclusion, the Macrobenthic community structure showed a distinct spatial and temporal trend, which seemed to be related to the water depth and sediment composition.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
• /
• v.18 no.1
• /
• pp.1-12
• /
• 2013

Acoustic backscatter profiles were measured by Eco-sounder along an east-west section in the mid-eastern Yellow Sea and at an anchoring station in the low salinity region off the Keum River estuary in September 2012, with observing physical water property structure by CTD. Tidal front was established around the sand ridge developed in 50 m depth region. Internal waves measured by Eco-sounder during low tide period in the eastern side of the sand ridge were nonlinear depression waves with wave height of 15 m and mean wavelength of 500 m. These waves were interpreted into tidal internal waves that were produced by tidal current flowing over the sand ridge to the southeast. When weakly non-linear soliton model was applied, propagation speed and period of these internal depression wave were 50 m/s and 16~18 min. Red tides by Dinoflagelates Cochlodinium were observed in the sea surface where strong acoustic scattering layer was raised up to 7 m. Hourly CTD profiles taken at the anchoring station off the Keum River estuary showed the halocline depth change by tidal current and land-sea breeze. When tidal current flowed strongly to the northeast during flood period and land-breeze of 7 m/s blew to the west, the halocline was temporally raised up as much as 2 m and acoustic profile images showed a complex structure in the surface layer within 5-m depth: in tens of seconds the declined acoustic structure of strong and weak scattering signals alternatively appeared with entrainment and intrusion shape. These acoustic profile structures in the surface mixed layer were observed for the first time in the coastal sea of the mid-eastern Yellow Sea. The acoustic profile images and turbidity data suggest that relatively transparent low-layer water be intruded or entrained into the turbid upper-layer water by vertical shear between flood current and land breeze-induced surface current.

• Korean Journal of Plant Resources
• /
• v.21 no.2
• /
• pp.117-127
• /
• 2008

The vascular plants in the Eco-Arboretum site, Mt. Gumwon appeared to be 369 taxa; 84 families, 217 genera, 319 species, 43 varieties and 7 forms. Based on the list of the rare plants, 2 taxa existed in the studied areas; Abies koreana (Preservation priority order; No. 73), Paeonia obovata (No. 97) and based on the list of Korean endemic plants, 12 families, 14 genera, 11 species, 3 varieties, 1 hybrid, 15 taxa existed; Cephalotaxus koreana, Abies koreana (Planted species), Carex okamotoi, Salix hallaisanensis, Salix purpurea var. japonica, Clematis trichotoma, Thalictrum actaefolium, Lespedeza ${\times}$ tomentella, Vicia nipponica, Stewartia koreana, Hypericum attenuatum var. confertissimum, Paulownia coreana (Planted species), Weigela subsessilis, Aster koraiensis (Planted species). Specific plant species by floral region were total 38 taxa; Paeonia obovata in class V , 13 taxa (Lilium leichtlinii var. tigrinum, Betula costata, Betula davurica, Ulmus davidiana, Spiraea frutschiana, Prunus maackii, Syringa reticulata var. mandshurica, Cynanchum inamoenum, Lonicera subhispida, Cacalia firma, etc.) in class III , 5 taxa (Heloniopsis orientalis, Chrysosplenium pilosum, Acer triflorm, Viola tokubuchiana var. takedana, Teucrium veronicoides, etc.) in Class II . 19 taxa (Dryopteris erythrosora, Arisaema ringens, Veratrum versicolor, Polygonatum inflatum, Salix glandulosa, Betula schmidtii, Alnus hirsuta, Quercus variabilis, Aconitum japuense, Dicentra spectabilis, Chrysosplenium flagelliferum, Impatiens noli-tangere, Ilex macropoda, Tilia amurensis, Fraxinus mandshurica, Trigonotis icumae, etc.)in class I . The naturalized plants in this site were 5 families, 13 genera, 15 taxa (Rumex acetocella, Rumex obtusifolius, Trifolium repens, Oenothera odorata, Erigeron annuus, Erigeron philadelphicus, Bidens frondosa, Taraxacum officinale, etc.) and naturalization rate was 4.1% of all 369 taxa vascular plants.

• Korean Journal of Clinical Laboratory Science
• /
• v.49 no.4
• /
• pp.446-454
• /
• 2017

Human papillomaviruses (HPVs) are major causes of cervical cancer. Sixteen high risk HPVs, including HPV 16, HPV 18, HPV31, HPV 33, HPV 35, HPV 39, HPV 45, HPV 51, HPV 52, HPV 53, HPV 56, HPV 58, HPV 59, HPV 66, HPV 68, and HPV 69 are found in cervical cancer. HPVs 16 and 18 are mainly presented in 70% of cervical cancer. Therefore, identifying the presence of these high-risk HPVs is crucial. The objective of this study is to establish the HPV ViroCheck for detecting 16 HR-HPVs and genotypes of HPVs 16 and 18, as well as to analyze the analytical performance of HPV ViroCheck. We performed the analytical sensitivity of HPV E6 / E7 genes of 16 high risk HPVs to confirm the limit of detection. Then, a cross reactivity of HPV ViroCheck with microorganisms and viruses related to the cervix were analyzed for analytical specificity. Analytical sensitivity of high risk HPV genotypes ranged from 1 to 100 copies when using cloned DNAs. The limit of detection was 10 cells for both SiHa and HeLa cells. Cervical-related microorganisms and viruses did not show cross-reactivity to HPV DNA. Moreover, the intra- and inter-assay coefficient variations (CVs) were below 5%. In conclusion, HPV Virocheck will be useful for the detection of 16 HR HPVs, as well as HPV 16 and HPV 18 genotypes rapidly.

• The Journal of Engineering Geology
• /
• v.29 no.2
• /
• pp.85-97
• /
• 2019

It can be observed that steep slopes ($65^{\circ}$ to $80^{\circ}$) consist of rock masses were kept stable for a long time. In rock-mass slopes with similar ground condition, steeper slopes than 1 : 0.5 ($63^{\circ}$) may be applied if the discontinuities of rock-mass slope are distributed in a direction favorable to the stability of the slope. In making a decision the angle of the slope, if the preliminary rock mass conditions applicable to steep slope are quantitatively setup, they may be used as guidance in design practice. In this study, the above rock mass was defined as a good continuum rock mass and the quantitative setup criterion range was proposed using RMR, SMR and GSI classifications for the purpose of providing engineering standard for good continuum rock mass conditions. The methods of study are as follows. The stable slope at steep slopes ($65^{\circ}$ to $80^{\circ}$) for each rock type was selected as the study area, and RMR, SMR and GSI were classified to reflect the face mapping results. The results were reviewed by applying the calculated shear strength to the stable analysis of the current state of rock mass slope using the Hoek-Brown failure criterion. It is intended to verify the validity of the preliminary criterion as a rock mass condition that remains stable on a steep slope. Based on the analysis and review by the above research method, it was analyzed that a good continuum rock mass slope can be set to Basic RMR ${\geq}50$ (45 in sedimentary rock), GSI and SMR ${\geq}45$. The safety factor of the LEM is between Fs = 14.08 and 67.50 (average 32.9), and the displacement of the FEM is 0.13 to 0.64 mm (average 0.27 mm). This can be seen as a result of quantitative representation and verification of the stability of a good continuum rock mass slope that has been maintained stable for a long period of time with steep slopes ($65^{\circ}$ to $80^{\circ}$). The setup guideline for a good continuum rock mass slope will be able to establish a more detailed setup standard when the data are accumulated, and it is also a further study project. If stable even on steep slopes of 1 : 0.1 to 0.3, the upper limit of steep slopes is 1 : 0.3 with reference to the overseas design standards and report, thus giving the benefit of ensuring economic and eco-friendlyness. Also, the development of excavation technology and plantation technology and various eco-friendly slope design techniques will help overcome psychological anxiety and rapid weathering and relaxation due to steep slope construction.

• Clean Technology
• /
• v.25 no.3
• /
• pp.256-262
• /
• 2019

Hydroxylammonium nitrate (HAN)-based liquid propellants are attracting attention as environmentally friendly propellants because they are not carcinogens and the combustion gases have little toxicity. The catalyst used to decompose the HAN-based liquid propellant in a thruster must have both low temperature activity and high heat resistance. The objective of this study is to prepare an Ru/alumina/metal foam catalyst by supporting alumina slurry on the surface of NiCrAl metal foam using a washing coating method and then to support a ruthenium precursor thereon. The decomposition activity of a HAN aqueous solution of the Ru/alumina/metal foam catalyst was evaluated. The effect of the number of repetitive coatings of alumina slurry on the physical properties of the alumina/metal foam was analyzed. As the number of alumina wash coatings increased, mesopores with a diameter of about 7 nm were well-developed, thereby increasing the surface area and pore volume. It was optimal to repeat the wash coating alumina on the metal foam 12 times to maximize the surface area and pore volume of the alumina/metal foam. Mesopores were also well developed on the surface of the Ru/alumina/metal foam catalyst. It was found that the metal form itself without the active metal and alumina can promote the decomposition reaction of the HAN aqueous solution. In the case of the Ru/alumina/metal foam-550 catalyst, the decomposition onset temperature was significantly lowered compared with that of the thermal decomposition reaction, and ${\Delta}P$ could be greatly increased in the decomposition of the HAN aqueous solution. However, when the catalyst was calcined at $1,200^{\circ}C$, the catalytic activity was lowered inevitably because the surface area and pore volume of the catalyst were drastically reduced and Ru was sintered. Further research is needed to improve the heat resistance of Ru/alumina/metal foam catalysts.

• Journal of Intelligence and Information Systems
• /
• v.29 no.3
• /
• pp.287-316
• /
• 2023

As global energy crisis and the COVID-19 pandemic have emerged as social issues, there is a growing demand for companies to move away from profit-centric business models and embrace sustainable management that balances environmental, social, and governance (ESG) factors. ESG activities of companies vary across industries, and industry-specific weights are applied in ESG evaluations. Therefore, it is important to develop strategic management approaches that reflect the characteristics of each industry and the importance of each ESG factor. Additionally, with the stance of strengthened focus on ESG disclosures, specific guidelines are needed to identify and report on sustainable management activities of domestic companies. To understand corporate sustainability strategies, analyzing ESG reports and news articles by industry can help identify strategic characteristics in specific industries. However, each company has its own unique strategies and report structures, making it difficult to grasp detailed trends or action items. In our study, we analyzed ESG reports (2019-2021) and news articles (2019-2022) of six companies in the 'Finance,' 'Manufacturing,' and 'IT' sectors to examine the sustainability strategies of leading domestic ESG companies. Text mining techniques such as keyword frequency analysis and topic modeling were applied to identify industry-specific, ESG element-specific management strategies and issues. The analysis revealed that in the 'Finance' sector, customer-centric management strategies and efforts to promote an inclusive culture within and outside the company were prominent. Strategies addressing climate change, such as carbon neutrality and expanding green finance, were also emphasized. In the 'Manufacturing' sector, the focus was on creating sustainable communities through occupational health and safety issues, sustainable supply chain management, low-carbon technology development, and eco-friendly investments to achieve carbon neutrality. In the 'IT' sector, there was a tendency to focus on technological innovation and digital responsibility to enhance social value through technology. Furthermore, the key issues identified in the ESG factors were as follows: under the 'Environmental' element, issues such as greenhouse gas and carbon emission management, industry-specific eco-friendly activities, and green partnerships were identified. Under the 'Social' element, key issues included social contribution activities through stakeholder engagement, supporting the growth and coexistence of members and partner companies, and enhancing customer value through stable service provision. Under the 'Governance' element, key issues were identified as strengthening board independence through the appointment of outside directors, risk management and communication for sustainable growth, and establishing transparent governance structures. The exploration of the relationship between ESG disclosures in reports and ESG issues in news articles revealed that the sustainability strategies disclosed in reports were aligned with the issues related to ESG disclosed in news articles. However, there was a tendency to strengthen ESG activities for prevention and improvement after negative media coverage that could have a negative impact on corporate image. Additionally, environmental issues were mentioned more frequently in news articles compared to ESG reports, with environmental-related keywords being emphasized in the 'Finance' sector in the reports. Thus, ESG reports and news articles shared some similarities in content due to the sharing of information sources. However, the impact of media coverage influenced the emphasis on specific sustainability strategies, and the extent of mentioning environmental issues varied across documents. Based on our study, the following contributions were derived. From a practical perspective, companies need to consider their characteristics and establish sustainability strategies that align with their capabilities and situations. From an academic perspective, unlike previous studies on ESG strategies, we present a subdivided methodology through analysis considering the industry-specific characteristics of companies.

• Journal of the Korean Society of Marine Environment & Safety
• /
• v.29 no.2
• /
• pp.197-206
• /
• 2023

Recently, the international community, including the International Maritime Organization (IMO), has strengthened regulations on air pollution emissions of ships, and eco-friendly ships are actively being developed to reduce exhaust gas emissions. Among them, rotor sail (RS), a wind-assisted ship propulsion system, is attracting attention again. RS is a cylindrical device installed on the ship deck, that generates hydrodynamic lift using a magnus effect. This is a next generation eco-friendly auxiliary propulsion technology, and Enercon company, which developed RS-applied ships, announced that fuel savings of more than 30% are possible. In this study, optimal installation conditions such as RS spacing and arrangement type were selected when multiple RSs were installed on ships. AR=5.1, SR=1.0, and D_e/D was fixed at 2.0 according to the RS arrangement, and the wind direction was considered only for the unidirectional +y-axis. Regarding arrangement conditions, five conditions were set at 3D intervals in the +x-axis direction from 3D to 15D and five conditions in the +y-axis direction from 5D to 25D. C_L, C_D and aerodynamic efficiency (C_L/C_D) were compared according to the square(□) and diamond(◇) shape arrangements. Consequently, the effect of RS on the longitudinal distance was not significantly different. However, in the case of RS flow characteristics according to the transverse distance, the interaction effect of RS was the greatest when the two RSs almost matched the wind direction. In the case of the RS flow characteristics according to the arrangement, notably, when the wind blew in the forward (0°) direction, the diamond (◇) arrangement was least affected by the backward flow between RSs.