• Journal of Life Science
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• v.32 no.7
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• pp.578-587
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• 2022

Korea, as the world's 7^th largest emitter of greenhouse gases, has raised the national greenhouse gas reduction target as international regulations have been strengthened. As it is possible to utilize coastal and marine ecosystems as important nature-based solutions (NbS) for implementing climate change mitigation or adaptation plans, the blue carbon ecosystem is now receiving attention. Blue carbon refers to carbon that is deposited and stored for a long period after carbon dioxide (CO₂) is absorbed as biomass by coastal ecosystems or oceanic ecosystems through photosynthesis. Currently, there are only three blue carbon ecosystems officially recognized by the Intergovernmental Panel on Climate Change (IPCC): mangroves, salt marshes, and seagrasses. However, the results of new research on the high CO₂ sequestration and storage capacity of various new blue carbon sinks, such as seaweeds, microalgae, coral reefs, and non-vegetated tidal flats, have been continuously reported to the academic community recently. The possibility of IPCC international accreditation is gradually increasing through scientific verification related to calculations. In this review, the current status and potential value of seaweeds, seagrass fields, and non-vegetated tidal flats, which are sources of blue carbon on the east coast, are discussed. This paper confirms that seaweed resources are the most effective NbS in the East Sea of Korea. In addition, we would like to suggest the direction of research and development (R&D) and utilization so that new blue carbon sinks can obtain international IPCC certification in the near future.

• Journal of Korean Tunnelling and Underground Space Association
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• v.24 no.5
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• pp.431-449
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• 2022

As many tunnels generally have been constructed, various experiences and techniques have been accumulated for tunnel design as well as tunnel construction. Hence, there are not a few cases that, for some usual tunnel design works, it is sufficient to perform the design by only modifying or supplementing previous similar design cases unless a tunnel has a unique structure or in geological conditions. In particular, for a tunnel blast design, it is reasonable to refer to previous similar design cases because the blast design in the stage of design is a preliminary design, considering that it is general to perform additional blast design through test blasts prior to the start of tunnel excavation. Meanwhile, entering the industry 4.0 era, artificial intelligence (AI) of which availability is surging across whole industry sector is broadly utilized to tunnel and blasting. For a drill and blast tunnel, AI is mainly applied for the estimation of blast vibration and rock mass classification, etc. however, there are few cases where it is applied to blast pattern design. Thus, this study attempts to automate tunnel blast design by means of machine learning, a branch of artificial intelligence. For this, the data related to a blast design was collected from 25 tunnel design reports for learning as well as 2 additional reports for the test, and from which 4 design parameters, i.e., rock mass class, road type and cross sectional area of upper section as well as bench section as input data as well as16 design elements, i.e., blast cut type, specific charge, the number of drill holes, and spacing and burden for each blast hole group, etc. as output. Based on this design data, three machine learning models, i.e., XGBoost, ANN, SVM, were tested and XGBoost was chosen as the best model and the results show a generally similar trend to an actual design when assumed design parameters were input. It is not enough yet to perform the whole blast design using the results from this study, however, it is planned that additional studies will be carried out to make it possible to put it to practical use after collecting more sufficient blast design data and supplementing detailed machine learning processes.

• Journal of the Korean Recycled Construction Resources Institute
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• v.9 no.2
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• pp.167-176
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• 2021

When producing recycled asphalt mix, it is important that the old binder of reclaimed asphalt pavement(RAP) should be well melted during blending in the mixer. The recycled asphalt mix is produced by instant mixing(IM) of all materials(RAP, virgin asphalt and new aggregates) all together in the mixer. However, in the same recycled mix, the binder around RAP aggregate was found to show higher oxidation level than the binder coated around the virgin aggregate because the old binder of RAP was not rejuvenated properly while instant mixing. The partially-rejuvenated RAP binder is assumed to be a high stiffness point in IM recycled mix. In this study, the stage mixing(SM) method was introduced; blending RAP and virgin asphalt for the first stage, and then mixing all together with hot new aggregates for the second stage. To compare the effect of the two mixing methods on moisture resistance of recycled mixes, a statistical t-test was performed between SM and IM using indirect tensile strength(ITS) and tensile strength ratio(TSR). Three conditioning methods were used; a 16-h freezing and then 24-h submerging, 48-h submerging, and 72-h submerging in 60℃ water. It was found that the TSR(=ITS_wet/ITS_dry) values of the mixes prepared by SM was clearly higher than the IM mixes, and coefficients of variation of SM mixes were lower than the IM mixes. It was also observed that the ITS_WET of SM was significantly different from the IM at α=0.05 level by statistical t-test. The ITS_WET of SM mix was reduced less than the IM mix in severer conditioned mixes. Therefore, it was concluded that the stage mixing method was an important blending technique for producing better-quality of recycled asphalt mixes, which would show higher moisture resistance than the recycled mixes produced by conventional instant mixing.

• Journal of the Korean Society of Floral Art and Design
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• no.43
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• pp.123-138
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• 2020

This study found Flower Jewelry works in the monthly magazine specializing in flower decoration for nine years from 2011 to 2019. Based on the analysis of the type of expression, method of expression, type and number of plant materials used, and the type and number of non-plant materials used for the flower jewelry found, it was conducted to find out the trend of flower jewelry in Korea. By expression type, a total of 96 works were analyzed as 20.83% for headdresses, 57.29% for necklaces, 5.21% for earrings, 6.25% for lists, and 10.42% for other works(χ²=94.833, p<.001). According to the analysis of the frequency of use of expression techniques, headdresses, necklaces, and lists for each work were produced using five to six different expression techniques and earrings were produced using two to four expression techniques. Material coupling techniques 34.43%, flower and leaf utilization 30.17%, visual techniques 16.63%, collectivization techniques 14.12%, technical highlighting techniques 4.26%, and other 0.39% (χ²=455.222, p<.001). The most frequently used techniques were framing techniques 16.63% and knotting techniques 16.44%. Plant materials used in flower jewelry were found to be 22.61% for Phalaenopsis spp., 13.48% for Gomphrena globosa, 9.57% for Gloriosa rothschildiana, 7.39% for Epidendrum cinnabarinum, 6.96% for Chamelaucium uncinatum and 4.78% for Craspedia globosa (χ²=718.104, p<.001). In the case of branch, the most common was used with 70.00% of the Cornus walteri, and 10.00% of Actinidia arguta, Celastrus orbiculatus, and Salix pseudolasiogyne were used respectively (χ²=10.800, p=.013). In the case of foliage, 24.65% Aspidistra elatior, 24.62% Asparagus asparagoides, 11.54% Senecio rowleyanus, and 6.15% Ceropegia woodii (χ²=269.385, p<.001). In the case of berries, 44.44% of the fruits of the Smilax china, 33.33% of the Hypericum patulum, and 11.11% of the Phytolacca americana were found (χ²=11.444, p =.022). Non-planting materials used in the manufacture of flower jewelry were found to be 47.34% of 2mm aluminium wire, 33.73% of copper wire and 10.06% of 1mm aluminum wire (χ²=186.704, p<.001). The figure was 53.57% for pearls, 12.50% for ribbons, and 4.14% for spangles and feathers.

• Journal of Korean Society of Forest Science
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• v.111 no.4
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• pp.548-556
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• 2022

In this study, basic data were obtained to determine the optimal cultivation method to achieve stable fruiting and yield increase in "Cheonhwang" jujube trees. Accordingly, thefructification, fruit characteristics, and yield according to tree age were analyzed. The mean (and range of) tree height, crown area, stem diameter near the root, clear stem length, number of main branches, and distance between main branches were 235.6 (217.4-253.8) cm, 3.5 (3.1-4.1) m², 5.5 (4.0-7.1) cm, 70.6 (66.2-72.7) cm, 9.7 (8.6-10.5), and 10.4 (7.9-14.2) cm, respectively. Correlationanalysis results indicated that tree age was positively correlated with crown area, stem diameter near the root, and clear stem length but not with the number of main branches. The mean number (and range) of fruit per fruit-bearing mother shoot and tree were 18.3 (16.7-18.3) and 170.7 (157.9-178.3), respectively. Tree age was not significantlycorrelated with fruiting characteristics (i.e., the numbers of fruit-bearing mother shoots per main branch, fruit-bearing shoots per fruit-bearing mother shoot, fruit per fruit-bearing shoot, and fruit per tree). Given that the shape of jujube trees is constantly managed according to the growing area and greenhouse type, the tree growth characteristics were more affected by tree management techniques than by tree age. The mean (and range of) fruit weight, fruit hardness, and soluble solid content were 28.6 (27.7-30.3) g, 29.4 (28.5-30.4) N, and 20.4 (19.3-21.0) °brix, respectively, and these fruit characteristics were not significantly correlated with tree age.The average yield per tree of the 'Cheonhwang' jujube cultivar was 4.9 (4.8-5.0) kg, which was not significantly correlated with tree age.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.40 no.5
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• pp.662-669
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• 1995

To clarify the effect of temperature during ripening on grain quality, rice plant which was grown under normal natural conditions untill heading stage was subjected various temperature regimes during grain filling stage. Three varieties, Odaebyeo, Hwaseongbyeo and Dongjinbyeo were used. Grains on primary and secondary-rachis branches were harvested seperately and measured specific gravity, grain size and weight. The optimum daily temperature for grain filling of rice during ripening period was about 22$^{\circ}C$ and grain filling under alternating temperature(26/18$^{\circ}C$, day /night) was better than constant temperature (22 /22$^{\circ}C$) based on 1, 000-grain weight and yield. Grain size based on volume per grain was smallest under the constant temperature of 22 /22$^{\circ}C$. The size of secondary-rachis branches was smaller than primary-rachis branch. The difference in size between primary and secondary-rachis branches was biggest in Hwaseongbyeo, followed by Odaebyeo and Dongjinbyeo. The temperature regimes treated did not influence the grain size difference between branches so much. The 1000-grain weight was lighter under high temperature than low temperature in Odaebyeo, but reversed tendency was observed in Dongjinbyeo of secondary rachis-branches.

• Journal of the Korean Institute of Landscape Architecture
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• v.51 no.2
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• pp.42-53
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• 2023

This paper explores the recent development of environmental aesthetics and critically examines the main agendas, claims, issues, and implications of everyday aesthetics, which is emerging as an important branch of environmental aesthetics. Environmental aesthetics began in the context of cultural change and environmentalism in the 1960s and expanded in the second half of the 20th century with a solid theoretical foundation. At the beginning of the 21st century, it entered a process of diversification of objects and subjects. Having reached academic maturity, environmental aesthetics has expanded into theoretical territory considering the urban environment and the human environment, providing practical coordinates as a discourse for planning and designing urban environments and landscapes. The most notable achievement of environmental aesthetics since the mid-2000s is the establishment of 'everyday aesthetics'. Yuriko Saito, who is leading the research on everyday aesthetics, expanded the objects and scope of aesthetic theory to everyday objects, events, activities, and environments. She excavates the microscopic and sensory aspects of everyday life, which have been overlooked by conventional art-centered aesthetics, through the lens of aesthetics. She reinterprets various layers of phenomena in contemporary urban landscapes and analyzes how the 'power of the aesthetic' hidden in everyday life profoundly affects the quality of life and the state of the world. Saito examines the appreciation of the distinctive characteristics and ambiance inherent in everyday objects and environments and proposes a 'moral-aesthetic judgment' to alert citizens to the environmental, social, and political consequences of everyday aesthetic appreciation and response. This paper identifies the issues and implications of everyday aesthetics as first, the expansion of aesthetics and the ambiguous everyday, second, the moral-aesthetic judgment and the aesthetics of care, and third, urban regeneration landscapes and aesthetic literacy. In particular, the moral virtues of everyday aesthetics that Saito proposes, such as care, thoughtfulness, sensitivity, and respect, provide a critical reference for the practice of contemporary urban regeneration landscapes. The 'aesthetic literacy' is a key concept demonstrating why an environmental aesthetics perspective is necessary to interpret everyday urban environments and landscapes.

• Korean Journal of Plant Resources
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• v.36 no.4
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• pp.402-412
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• 2023

Peucedanum japonicum Thunberg is a biennial plant that usually flowers and dies after seed setting at 2^nd year. We inspected the flowering and fertilization characteristics to establish the breeding system. The plant forms complex umbel inflorescences consisting of multiple umbellets and numerous flowers. Each flower is bisexual but allogamous because of protandry. A flower bloomed for three days with matured pollen and no stigma appearance. Inspection of pollen tube growth indicates that the pollen viability can be maintained for up to 3~7 days after first flowering (DAF). In a umbellet, flowers bloomed during 1~5 DAF and the pollen maintained viability during 3~10 DAF, and the pistil developed and maintained fertility during 8~12 DAF. Theoretically, self-pollination can be possible during 8~10 DAF in the same umbellet. Approximately 4.4% of seeds were developed by self-pollination among flowers in an enveloping solitary umbel. There is at least a 9~10 days difference for the development of an umbel with another umbel at the next branch, which indicates pollination can be permitted between different branches in an individual plant. Finally, we have established a rapid breeding method to shorten the breeding cycle to one year from two years by integrating the flowering and pollination characteristics.

• Journal of Nutrition and Health
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• v.56 no.6
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• pp.629-640
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• 2023

Purpose: Non-alcoholic fatty liver disease (NAFLD) is characterized by the accumulation of fat in the liver which is not a result of excessive alcohol consumption. Its global prevalence was estimated to be approximately 32% in the years 1994-2019. More than half of obese individuals and patients with diabetes are reported to have NAFLD as a comorbidity. This study aimed to investigate the impact of the autumn olive (Elaeagnus umbellata Thunb.) berry on insulin resistance and steatosis in rats fed a high-fructose diet. Methods: Six-week-old Wistar rats were divided into four groups. The control group received a diet consisting of 65% corn starch, while the fructose and experimental groups were fed a diet comprising 65% fructose (FRU) and an FRU diet containing 0.5% (low-dose autumn olive berry group; LAO) or 1.0% (high-dose autumn olive berry group; HAO) ethanol extract of autumn olive berry, respectively, for 10 weeks. Results: The HAO group exhibited significantly lower blood glucose levels compared to the fructose-fed group. Both the LAO and HAO groups showed a substantial reduction in serum insulin levels and insulin resistance when compared to the fructose-fed group. The consumption of LAO and HAO significantly ameliorated dyslipidemia and reduced the levels of triglycerides in the liver compared to the fructose-fed group. Additionally, the consumption of HAO resulted in lower serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) activities compared to the fructose group. The hepatic expression of the sterol regulatory element-binding protein-1c (SREBP-1c) and carbohydrate-responsive element-binding protein (ChREBP) was significantly reduced in the LAO and HAO groups compared to the fructose group. Conclusion: Autumn olive berries improved steatosis by ameliorating insulin resistance and down-regulating the lipogenesis proteins in rats fed on high fructose diet.

• Korea Trade Review
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• v.48 no.3
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• pp.23-41
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• 2023

The seller and the buyer write down the agreed details in the trade contract as trade contract clauses. In the case where a letter of credit is agreed to be the payment condition, the buyer shall open a letter of credit to the seller with the shipping date specified in the trade contract through its bank. In this case, the legal relationship between the performance date of the trade contract and the shipment date of the letter of credit, the change of the performance date of the trade contract due to the change of the trade contract and the change of the shipment date specified in the letter of credit, the seller's letter of credit A problem arises in the legal interpretation of the approval period and the change request period. Therefore, this paper analyzed the precedents of the Seongnam Branch of the Suwon District Court and the Seoul High Court related to these legal issues. The performance date of a trade contract is the seller's delivery date and the buyer's payment date. In the letter of credit transaction, the date of performance of the trade contract is regarded as the date of shipment and the date of negotiation of documents specified in the letter of credit. The seller must decide whether to accept the letter of credit within 5 banking days after receiving the letter of credit from the buyer. After this period has elapsed, the seller cannot refuse the letter of credit. However, if the buyer is unable to decide whether to accept the letter of credit within 5 banking days due to reasons attributable to the buyer, the delivery date specified in the letter of credit will be extended. If the seller requests an amendment to the letter of credit, the buyer must accept it and open the letter of credit the seller desires to the seller. If the buyer refuses the seller's request to change the letter of credit, company A has the obligation to change and reopen the letter of credit as requested by company B. Expect by agreeing on the quotation As it is a fundamental breach of contract stipulated in Article 25 of the United Nations Convention on Contracts for the International Sale of Goods, company B can cancel the trade contract and claim damages from company A. Compensation for damages caused by Company A's breach of the trade contract shall be an amount equal to the loss suffered by Company B as a result of the breach, including loss of profits.