• Journal of the Korean Society of Marine Environment & Safety
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• v.29 no.7
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• pp.950-957
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• 2023

For safe mooring and towing between the ship and port, the equipment must be designed in accordance with the relevant international regulations. However, some small shipyards and engineering companies often do not fully comprehend the core contents. Therefore, the international regulations regarding towing and mooring equipment are reviewed and the bollard and chock are newly developed based on the Mooring Equipment Guideline 4 (MEG4) standards. A bollard is a mooring equipment used to fix a mooring rope to the hull. It has two columns and is mostly used in a figure eight pattern knots under the mooring condition. The chock, which is used to change the mooring rope direction coming into the ship from outside, is manufactured using a casting with curvature. The two mooring equipment are widely used in the stern, bow, and mid-side. Owing to the increase in the size of container vessels and LNG ships, the mooring rope load has increased and the safe working load of the mooring equipment must be revised. This study summarizes and examines the results of the allowable stress method obtained using finite element analysis modelling. To consider the mesh size effect, a reasonable criteria was suggested by referring the existing class guidance. Additionally, the safe working load was verified through nonlinear collapse analysis, and the elastic region against load increments was confirmed. Furthermore, the proposed evaluation method can be used to develop similar equipment in the near future.

• Journal of Nutrition and Health
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• v.56 no.6
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• pp.615-628
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• 2023

Purpose: Increasing levels of domestic fine dust (DFD) have emerged as a serious problem that threatens public health by causing chronic respiratory diseases and skin aging. The present study was performed to investigate the inhibitory effects of Gryllus bimaculatus (the two-spotted cricket), which has recently attracted attention as an edible insect in South Korea, on DFD-induced aging and inflammation. Methods: To verify that DFD causes skin aging and investigate the anti-aging effect of an aqueous ethanolic-Gryllus bimaculatus extract (AE-GBE), human diploid fibroblasts (HDF) were treated with 100 ㎍/mL of European reference material (ERM)-CZ100 dust for 24 hrs in the presence or absence of 100 ㎍/ml AE-GBE. Aging and cellular toxicities were assessed by measuring reactive oxygen species (ROS) levels, DNA fragmentation, and β-galactosidase activity. The protein levels of cyclooxygenase (COX) 2, matrix metalloproteinase (MMP)-1, and collagen were measured by western blot, and the mRNA expressions of inflammation-related genes were assayed by quantitative reverse transcriptase polymerase chain reaction. Results: Treatment with ERM-CZ100 induced an aged phenotype in HDF cells, as evidenced by increased ROS levels, DNA fragmentation, and senescence-associated β-galactosidase activity, but cotreatment with AE-GBE significantly reduced these inductions. The mRNA expressions of pro-inflammatory cytokines, such as interleukin (IL)-1β, IL-6, and tumor necrosis factor-α, induced by ERM-CZ100 were also reduced by AE-GBE cotreatment, which also reduced COX2 expression. Moreover, ERM-CZ100-induced MMP-1 expression and reduced collagen type I expression were recovered by AE-GBE treatment. Conclusion: These results suggest that AE-GBE is a potential treatment for domestic fine dust-induced skin inflammation and inflammaging.

• The Journal of the Acoustical Society of Korea
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• v.42 no.6
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• pp.594-602
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• 2023

To date, research on heavy floor impact noise has mainly been conducted. The reason is that in the case of lightweight floor impact noise, sufficient performance could be secured with only the floating floor structure and floor finishing materials. In the case of heavy floor impact noise in a floating floor structure, the reduction performance can be predicted to some extent by measuring the dynamic elasticity of the floor cushioning material. However, with the recent introduction of the post-measurement system, various floor structures are being developed. In particular, many non-floating floor structures that do not use cushioning materials are being developed. In floor structures where cushioning materials are not used, the finishing material will have a significant impact on lightweight floor impact noise. However, research on floor finishing materials is currently lacking. In this study, as a basic research on the development of various floor finishing materials for effective reduction of lightweight floor impact noise, various materials used as floor finishing materials for apartment complexes were selected, the sound insulation performance of lightweight floor impact noise was measured in an actual laboratory, and vibration characteristics were identified through simple experiments. The purpose was to confirm the predictability of light floor impact noise.

• Journal of the Korean Society of Radiology
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• v.17 no.6
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• pp.1009-1015
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• 2023

This study was a one-group pretest-posttest design experimental study that attempted to verify the effects of applying the Havruta learning method on the academic self-efficacy, academic achievement, and communication skills of radiology college students. This study was conducted from May 1 to June 23, 2023, and applied the Havruta learning method for 6 weeks to 38 second-year radiologists taking a radiology technology course at a university in Jeollanam-do. SPSS/WIN 21.0 was used for data analysis, the reliability of the scale was verified, the subject's general characteristics, pre-test values and post-test values for measurement variables were verified with descriptive statistics, and the difference between before and after the Havruta learning method was verified with paired t-test. Research results show that the Havruta learning method improves academic self-efficacy (t=-2.70, p<.001), academic achievement (t=-2.87, p=.006), and communication skills (t=-2.76, p=.008). showed a statistically significant difference. As a result, Havruta learning method was confirmed as an effective learning method that improves academic self-efficacy, academic achievement, and communication skills of radiology college students. In the future, expanded application of the Havruta learning method will be necessary.

• Journal of Advanced Navigation Technology
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• v.25 no.6
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• pp.433-440
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• 2021

The problem of maritime accidents due to the carelessness of fishing vessels, which is affected by the aging of fishing vessel operators. And there is navigation, communication and fish finder that is installed inside the narrow bridge of a fishing vessel. Therefore these system are monitors as many as of each terminal, which is bad influence on obscuring view of front sea from a fishing vessel bridge. In addition a large problem, it is occurs to reduce of the information recognition ability due to the confusion, which is can not check the display information each of screen equipments. Therefore, there has been demand to simply integrated the equipment, and it has wanted the integrated support system of these equipment. The display must be provided on a fishing vessels such as electronic charts, communications equipments and fish detection into one case. In this paper, the integrated system will be installed the GPS plotter, AIS, VHF-DSC, V-pass, fish finder and power supply in the narrow wheelhouse on a fishing vessel, which is configured in one case and operated by multi function display (MFD). The MFD is integrated to simplify for several multi terminals and provided necessary information on a single screen. This integration fishery support system will has improved in sea safety operation and fishery environment of fishing vessels by this implementation.

• Journal of Life Science
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• v.33 no.12
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• pp.978-986
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• 2023

Inflammation by the innate immune system is a protective mechanism of the organism against infection-mediated environmental factors. It is also responsible for the pathogenesis of various human diseases, including the progression of cancer. Lichens are receiving increasing attention as a source of bioactive molecules with therapeutic potential for a variety of diseases. Additionally, the antioxidant, anti-inflammatory, and anticancer potential of lichen and its secondary metabolites have been widely reported. However, the underlying mechanism is still unknown. In the present study, to investigate molecular mechanisms of anti-inflammation and anti-cancer activity in the Antarctic lichen, Usnea aurantiaco-atra, methanol extract of Usnea aurantiaco-atra (MEUS) was used in vitro assays in RAW 264.7 macrophages cell and HCT116 colon cancer cells. Based on our data, MEUS had the anti-inflammatory activity through the modulation of main inflammatory indicators such as COX-2, IL-6, iNOS, TNF-α and NO production in a concentration-dependent manner. In addition, we observed that MEUS had cytotoxic activity against HCT116 colon cancer cells in a concentration-dependent manner, leading to a significantly reduced proliferation of the cancer cells through apoptotic induction by activating caspase-3. Taken together, this work firstly reported the anti-inflammatory and anti-cancer activities of an Antarctic lichen, Usnea aurantiaco-atra, and MEUS may provide a new insight into the molecular mechanisms underlying a link between inflammation and cancer.

• Journal of the Korean Society of Marine Environment & Safety
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• v.29 no.6
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• pp.653-658
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• 2023

In systems like the combat management system of a naval ship or smart city of civilians, where many sensors and actuators are connected, the middle-ware DDS (Data Distribution Service) is mainly used to transmit large amounts of data. It is scalable and can effectively respond to the increase in sensors or equipment connected to the system in the future. The engineering control system (ECS), which plays an important role similar to the combat management system of a naval ship, still uses Server-Client model with industrial protocols such as Modbus and CAN (Controller Area Network) bus, to transmit data, which is unfavorable in terms of scalability. However, as automation and unmanned systems advance, more sensors and actuators are expected to be added, necessitating substantial program modification. DDS can effectively address such situations. The purpose of this study is to confirm the development possibility of an integrated monitoring and control system of a ship by using OpenDDS, which follows the OMG (Object Management Group) standard among the middle-ware DDS used in the combat management system. To achieve this goal, field equipment simulators and an ECS server were configured to perform field equipment data input/output and simulation using DDS was performed. The ECS prototype successfully handled data transmission, confirming that DDS is capable of serving as the middle-ware for the ECS of a ship.

• Korean Journal of Environment and Ecology
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• v.37 no.5
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• pp.392-402
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• 2023

This study was conducted to understand the characteristics of the plant society in Cheongwansan Provincial Park, which lacks research on plants, and to establish basic data necessary for sustainable vegetation management and provincial park research. This study set up 126 quadrats were installed in Cheongwansan Provincial Park to investigate the species that emerged, and interspecies association analysis was conducted focusing on species excluding rare species. The results were written in a sociogram using the Gephi 0.10 program, modular analysis was conducted to distribute groups between adjacent nodes, and network centrality and structure analysis were conducted. As a result of the analysis, the Smilax china showed the highest frequency of appearance in the survey area. Next, it was found to be high in the order of Quercus serrata, Eurya japonica, Styrax japonicus, and Sasa borealis. Interspecies association analysis was conducted on 69 species excluding rare species, and plant social networks were visualized based on benign binding. The Plant Social Network consists of 69 nodes and 396 connecting lines, and one species formed interspecies bonds with an average of about 17.9 species, connecting each other in 2.3 steps. 69 species were divided into three groups through modular analysis, and the first group consisted mainly of evergreen broad-leaved and trees that appeared in warm-temperate region, and the second group consisted mainly of deciduous broad-leaved. The three groups were mainly divided into trees that grow well in sunny and dry sunlight.

• Journal of the Korean Society of Marine Environment & Safety
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• v.29 no.6
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• pp.609-619
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• 2023

This study aimed to investigate the formation of the social perception of domestic maritime sports using text mining analysis of keywords and topics from domestic media coverage over the past 10 years related to representative maritime sports, including yachting, rowing, and canoeing. The results are as follows: First, term frequency (TF) and word cloud analyses identified the top keywords: "maritime," "competition," "experience," "tourism," "world," "yachting," "canoeing," "leisure," and "participation." Second, semantic network analysis revealed that yachting was correlated with terms like "maritime," "industry," "competition," "leisure," "tourism," "boat," "facilities," and "business"; rowing with terms like "competition" and "Chungju"; and canoeing with terms like "maritime," "competition," "experience," "leisure," and "tourism." Third, topic modeling analysis indicated that yachting, rowing, and canoeing are perceived as elite sports and maritime leisure sports. However, the perception of these sports has been demonstrated to have little impact on society, public opinion, and social transformation. In summary, when considering these results comprehensively, it can be concluded that yachting and canoeing have gradually shifted from being perceived as elite sports to essential elements of the maritime leisure industry. Contrariwise, rowing remains primarily associated with elite sports, and its popularization as a maritime leisure sport appears limited at this time.

• Journal of Korean Society of Forest Science
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• v.113 no.2
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• pp.187-197
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• 2024

In this study, we aimed to identify the factors influencing post-fire mortality in Korean red pine (Pinus densiflora) using Cox's proportional hazards model and analyze the impact of these factors. We monitored the mortality rate of fire-damaged pine trees for seven years after a forest fire. Our survival analysis revealed that the risk of mortality increased with higher values of the delta normalized difference vegetation index (dNDVI), delat normalized burn ratio (dNBR), bark scorch index (BSI), bark scorch height (BSH) and slope. Conversely, the risk of mortality decreased with higher elevation, greater diameter at breast height (DBH), and higher value of delta moisture stress index (dMSI) (p < 0.01). Verification of the proportional hazards assumption for each variable showed that all factors, except slope aspect, were suitable for the model and significantly influenced fire occurrence. Among the variables, BSI caused the greatest change in the survival curves (p < 0.0001). The environmental change factors determined through remote sensing also significantly influenced the survival rates (p < 0.0001). These results will be useful in establishing restoration plans considering the potential mortality risk of Korean red pine after a forest fire.