• Journal of the Korean Institute of Landscape Architecture
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• v.49 no.6
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• pp.37-48
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• 2021

Roadside pollution has been identified as the main cause of PM_2.5 in urban areas. Green infrastructure has been understood to mitigate air pollution from roadside traffic effectively, but complication depend on environmental variables. This study aimed to investigate the characteristic of PM_2.5 by the type of space in an urban park located in Songsanghyeon Plaza, surrounded by a 12-lane road on all sides. Type of space was typically classified as roadside square (A), sunken square (B), a mix of trees and hedges/shrubs (C), trees only (D), and grass square (E) according to the land-use type and layers of trees. PM_2.5 was measured for nine days, three days for three different Air Quality Forecasts-Good level (0~15㎍/m³), Moderate level (16~35㎍/m³), and Unhealthy level (36~75㎍/m³). The analysis result was as follows. At good levels, there was statistical significance in the order of D, E < B, C < A. In the case of moderate levels and unhealthy levels, D and E were statistically lower than other land-use types. The characteristic of PM_2.5 in the urban park by type of space was affected by atmospheric flow into the road. The relatively high concentration of A and C was located near the roads. Although B was far away from the road, the reason for the high concentration of PM_2.5 was that no structures blocked the air pollution. Thanks to the type of space C, filtering the air pollution from the roads, the concentration of PM_2.5 in D and E was relatively low.

• Journal of the Korean Institute of Landscape Architecture
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• v.50 no.4
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• pp.63-76
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• 2022

This study was conducted to compare the perceptions of the park use status, importance, and satisfaction of users in the first implemented and completed Uijeongbu Jikdong Neighborhood Park among the private park special projects carried out as a countermeasure for long-term non-execution of urban parks. To this end, in the initiated project, apartment residents and non-residents were classified according to the promotion plan, and a questionnaire research on importance and satisfaction was conducted to analyze the park use status and IPA(importance-performance analysis). First, as a result of the analysis of the current situation in terms of locational characteristics that occur during the promotion of special projects for private parks, unlike the mountainous areas, the targeted site was close to flat land, indicating that users' satisfaction with the landscape was high. Second, the access of the apartment residents in the initiated project site was easy. Thus, the use rate of residents was relatively higher than that of the non-residents. Third, differences in perception by item were identified through the analysis of IPA and the establishment of strategies. In quadrant I, among the facilities and services, installing restrooms was the priority for residents, and parking facilities and rest facilities were the priority than installing restrooms for non-residents. In quadrant II, overall scores for residents and non-residents were similar, but the distance to the park was in quadrant III due to the low level of satisfaction among non-residents. In this study, the difference in perception between residents and non-residents may cause problems in access and facilities in managing the park in the future. Therefore, it would be necessary to find a way to improve it by establishing a management strategy that takes into account the difference in the perception of residents after construction. In addition, through the results of this study, it was judged that the purpose of park development, the selection of types of parks, and the selection of plans and management indicators for each kind would be significant in the promotion of initiated projects in the planning of park development.

• Development and Reproduction
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• v.12 no.3
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• pp.251-259
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• 2008

The plasticizer di(2-ethylhexyl)phthalate(DEHP) is one of the most well known endocrine disrupting chemicals (EDCs) because of its strong anti-androgenic effects on the reproductive and developmental process in male rodents and human. The present study was performed to examine whether prepubertal exposure to DEHP can make any alteration during the maturation of accessory sex organs in male rats. As a result, there was no significant change in body weights, serum T levels and tissue weights except of seminal vesicle and ventral prostate in DEHP-treated animals compared to vehicle-treated ones. The seminal vesicle weights in high-dose group (200 mg/kg) were significantly lower than those from the control group (p<0.05), and ventral prostate weights were significantly lower than those from the control group (p<0.05) in both low-dose (20 mg/kg) and high-dose group. Histological studies revealed that the seminal vesicles from DEHP-treated groups showed reduced areas of mucosal folds. Pseudostratified columnar epithelia were observed in the ventral prostates of DEHP-treated samples while cuboidal epithelia were found in the control group. The transcriptional activities of ER-$\alpha$ in seminal vesicle from high-dose group (p<0.05) were significantly higher than those from the control group, and ER-$\beta$ expression was significantly decreased in low-dose group (p<0.05) compared to the control. In ventral prostate, ER-$\beta$ mRNA levels from low-dose group (p<0.05) were significantly lower than those from the control group, and significantly increased in high-dose group (p<0.01). AR expressions, however, were not significantly different in all experimental groups of both seminal vesicle and ventral prostate. In conclusion, the present study demonstrated that (i) adverse effect (s) of DEHP on sexual maturation during prepubertal period could be limited, (ii) seminal vesicle and prostate gland were sensitive targets to DEHP in prepubertal rats and (iii) the deleterious effects of DEHP might be mediated through ER-associated mechanism.

• Journal of the korean academy of Pediatric Dentistry
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• v.50 no.1
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• pp.65-74
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• 2023

This study compared the surface roughness and microbial adhesion characteristics of Omnichroma, a novel composite resin developed using "smart chromatic technology", with those of two other conventional composite resins with different filler compositions. A total of 144 specimens were fabricated using 3 types of composite resins: Omnichroma (nano-spherical), Filtek Z350XT (nanofill), and Tetric N-Ceram (nanohybrid) and, divided into 3 groups of 48. Finishing was performed using tungsten carbide burs. Specimens were then divided into 3 subgroups using different polishing methods: Control, SofLex, and PoGo. Surface roughness was analyzed quantitatively and qualitatively using an atomic force microscope and a scanning electron microscope. Microbial adhesion was assessed by culturing Streptococcus mutans on the specimens for 24 hours and then measuring colony-forming units attached to the upper surface. The surface roughness (Ra) of Omnichroma was 0.123 ㎛ after finishing, and it exhibited a smooth surface compared to the other resins. However, after polishing, there were no significant differences in the surface roughness between the three composite groups, regardless of the polishing methods. The surfaces of the Control subgroups were significantly rougher than those of the SofLex subgroups in all 3 composite groups. However, except for Tetric N-Ceram, there were no significant differences between the Control and PoGo subgroups in the other composite groups. Microbial adhesion assessment showed no significant differences between any of the 3 composite resin subgroups; however, Omnichroma exhibited higher microbial adhesion than the other two composites. No significant correlation was observed between surface roughness and microbial adhesion.

• Journal of the Daesoon Academy of Sciences
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• v.44
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• pp.1-52
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• 2023

Incantations are reflected in the fundamentals of the Daesoon faith system and are, thus, key to its understanding. Jeungsan, the yeonwon (fountainhead, 淵源) of the Daesoon faith, created new incantations or transformed existing ones that had been used in old religious traditions such as Buddhism and Daoism. However, there has been no in-depth academic research on Jeungsan's incantations until now. This study aims to academically clarify the incantatory archetypes of Jeungsan's incantations based on documents published until the 1970s. Jeungsan's incantations are then compared to those of Mugeuk-do (Limitless Dao) in the 1920s and Taegeuk-do (Great-Ultimate Dao) in the 1950s. Jeongsan's transformed incantations are analyzed through this process. Jeongsan reflected the faith system in Jeungsan's incantations during the period of Mugeuk-do. He transformed the incantations to achieve his goal and realize his wishes by arranging terms that referred to himself before the optative words of the incantations. Jeongsan made several changes to the incantations in the 1950s. First, the majority of incantations used in Mugeuk-do were discarded. This meant making partial changes to the faith system by reflecting awareness because the corresponding incantations were no longer necessary as the Degree Number calibrated by Jeungsan had been realized. Second, Jeongsan organized the incantations in use and institutionalized their instructions. This reflected the essential doctrinal system of the Daesoon faith, namely the completion of the true dharma by Jeongsan. Considering this doctrine, that is, the Fifty Year Holy Work (五十年工夫), the true dharma can be presumed to have been realized before the death of Jeongsan. Accordingly, the institutionalizing and organizing of the incantations were indispensable until the mid-to-late 1950s. Jeongsan, the founder of the Daesoon order, posited himself as the successor of religious orthodox lineage and as the figure who would complete the true dharma by realizing the Degree Number calibrated by Jeungsan. Therefore, Jeongsan interpreted Jeungsan's incantations to be a rough sketch of the Daesoon faith system that had been drawn for him in advance by Jeungsan. Accordingly, Jeongsan transformed Jeungsan's incantations and used them to realize the Degree Number, which Jeungsan had planned. Simultaneously, Jeongsan declared that he would fulfill the Degree Number and establish the true dharma by changing those incantations.

• Journal of the Korean Society of Marine Environment & Safety
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• v.29 no.5
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• pp.479-487
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• 2023

Recently, the destructive power of typhoons is continuously increasing owing to global warming. In a situation where the installation of floating wind turbines is increasing worldwide, concerns about the huge loss and collapse of floating offshore wind turbines owing to strong typhoons are deepening. A new type of disconnectable mooring system must be developed for the safe operation of floating offshore wind turbines. A new submersible mooring pulley considered in this study is devised to more easily attach or detach the floating of shore wind turbine with mooring lines compared with other disconnectable mooring apparatuses. To investigate the structural safety of the initial design of submersible mooring pulley that can be applied to an 8MW-class floating type offshore wind turbine, scale-down structural models were developed using a 3-D printer and structural tests were performed on the models. For the structural tests of the scale-down models, tensile specimens of acrylonitrile butadiene styrene material that was used in the 3-D printing were prepared, and the material properties were evaluated by conducting the tensile tests. The finite element analysis (FEA) of submersible mooring pulley was performed by applying the material properties obtained from the tensile tests and the same load and boundary conditions as in the scale-down model structural tests. Through the FEA, the structural weak parts on the submersible mooring pulley were reviewed. The structural model tests were conducted considering the main load conditions of submersible mooring pulley, and the FEA and test results were compared for the locations that exceeded the maximum tensile stress of the material. The results of the FEA and structural model tests indicated that the connection structure of the body and the wheel was weak in operating conditions and that of the body and the chain stopper was weak in mooring conditions. The results of this study enabled to experimentally verify the structural safety of the initial design of submersible mooring pulley. The study results can be usefully used to improve the structural strength of submersible mooring pulley in a detailed design stage.

• Journal of Korea Entertainment Industry Association
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• v.13 no.3
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• pp.193-202
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• 2019

This study focuses on what changes are required as to a curriculum of dance department in the university in the age of the 4th industrial revolution. By comparing and analyzing the curricula of dance department in the five universities in Seoul, five academic subjects as to curricula of dance department, which covers what to learn for dance education in the age of the 4th industrial revolution, are presented. First, dance integrative education, the integration of creativity and science education, can be referred to as a subject that stimulates ideas and creativity and raises artistic sensitivity based on STEAM. Second, the curriculum characterized by prediction of the future prospect through Big Data can be utilized well in dealing with dance performance, career path of dance-majoring people, and job creation by analyzing public opinion, evaluation, and feelings. Third, video education. Seeing the images as modern major media tends to occupy most of the expressive area of art, dance by dint of video enables existing dance work to be created as new form of art, expanding dance boundaries in academic and performing art viewpoint. Fourth, VR and AR are essential techniques in the era of smart media. Whether upcoming dance studies are in the form of performance or education or industry, for VR and AR to be digitally applied into every relevant field, keeping with the time, learning about VR and AR is indispensable. Last, the 4th industrial revolution and the curriculum of dance art are needed to foresee the changes in the 4th industrial revolution and to educate changes, development and seeking in dance curriculum.

• Korean Journal of Ecology and Environment
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• v.56 no.1
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• pp.94-103
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• 2023

Cyanobacterial resting cells, such as akinetes, are important seed cells for cyanobacteria's early development and bloom. Due to their importance, various methods have been attempted to isolate resting cells present in the sediment. Ludox is a solution mainly used for cell separation in marine sediments, but finding an accurate method for use in freshwater is difficult. This study compared the two most commonly used Ludox methods (direct sediment treatment and sediment distilled water suspension treatment). Furthermore, we proposed a highly efficient method for isolating cyanobacterial resting cells and eDNA amplification from freshwater sediments. Most of the resting cells found in the sediment were akinete to the Nostocale and were similar to those of Dolichospermum, Cylindrospermum, and Aphanizomenon. Twenty times more akinetes were found in the conical tube column using the sediment that had no treatment than in the sample treated by suspending the sediment in distilled water. Akinete separated through Ludox were mainly spread over the upper and lower layers in the column rather than concentrated at a specific depth in the column layer. The mibC, Geo, and 16S rDNA genes were successfully amplified using the sediment directly in the sample. However, the amplification products of all genes were not found in the sample in which the sediment was suspended in distilled water. Therefore, 5 g to 10 g of sediment is used without pretreatment when isolating cyanobacterial resting cells from freshwater sediment. Cell isolation and gene amplification efficiency are high when four times the volume of Ludox is added. The Ludox treatment method presented in this study isolates cyanobacterial resting cells in freshwater sediment, and the same efficiency may not appear in other biotas. Therefore, to apply Ludox to the separation of other biotas, it is necessary to conduct a pre-experiment to determine the sediment pretreatment method and the water layer where the target organism exists.

• Journal of Bio-Environment Control
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• v.32 no.2
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• pp.97-105
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• 2023

Concentration of nitrogen, one of the major elements, and ratio of two nitrogen forms (NH₄⁺ and NO₃^-) in the nutrient solution affect the quality and food safety of fresh vegetable produce. This study was conducted to find an appropriate strength and NH₄⁺:NO₃^- ratio of a nutrient solution for growth and development of a Romaine lettuce (Lactuca sativa L. var. longiflora) 'Caesar Green', a representative leafy vegetable, grown in a home hydroponic system. In the first experiment, plants were grown using three types of nutrient solution: A commercial nutrient solution (Peters) and two strengths (GNU1 and GNU2) of a multipurpose nutrient solution (GNU solution) developed in a Gyeongsang National University lab. Plants grown with the GNU1 and GNU2 had greater shoot length, leaf length and width, and biomass yield than Peters. On the other hand, the root hairs of plants grown with Peters were short and dark in color. Tissue NH₄⁺ content in the Peters was higher than that of the GNU1 and GNU2. The higher contents of NH₄⁺ in this solution may have caused ammonium toxicity. In the second experiment, eight treatment solutions, combining GNU1 and GNU2 solutions with four ratios of NO₃^- :NH₄⁺ named as 1, 2, 3 and 4 were used. Both experiments showed more growth in the GNU2 group, which had a relatively low ionic strength of the nutrient solution. The growth of Romaine lettuce showed the greatest fresh weight along with low tissue NO₃^- content in the GNU2-2. This was more advantageous in terms of food safety in that it suppressed the accumulation of surplus NO₃^- in tissues due to the low ionic trength of the GNU2 subgroup. In addition, this is preferable in that it can reduce the absolute amount of the input of inorganic nutrients to the nutrient solution.

• Journal of the Korean Orthopaedic Association
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• v.54 no.6
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• pp.528-536
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• 2019

Purpose: This study examined the effects of a weekly teriparatide on the change in vertebral compression ratio, back pain, and vertebral fracture healing in osteoporosis patients with vertebral compression fractured induced by low energy trauma. Materials and Methods: From January 2016 to December 2017, 57 patients with severe osteoporotic vertebral fractures with a T score of -3.5 or less were included in this study. The changes in the vertebral compression ratio, visual analogue scale (VAS), Oswestry disability index (ODI) for at least 6 months were examined. The morphology of bone marrow edema and the presence of intervertebral cleft, osteocalcin, and N-terminal telopeptide (NTx) were also investigated. Results: The mean compression ratio was 20% in the experimental group (teripratide group) at 3 months, and 38% in the control group. A significant difference in the compression ratio of the vertebral body over time was observed (p<0.05; t-test). A comparison of the compression ratio of the vertebral body with the follow-up duration in each group showed no significant increase in the, compression (p=0.063) in the experimental group and a significant increase in the control group (p<0.05). The mean time to reach the plateau of the compression rate was one month in the experimental group and three months in the control group. The VAS score in the experimental and control group was 0.39 and 1.07 points, respectively. The ODI score in the experimental and control group was 33.72 and 39.52, respectively. At the last follow-up radiographs, there were no cases with an intervertebral cleft (0%) in the experimental group and 1 case (2.2%) in the control group. A significant difference in the osteocalcin level was observed between the injury and 6 months after the injury (p=0.003). In addition, there was no significant difference in the NTx level between the injury and 6 months after injury (p=0.960). Conclusion: In vertebral compression fractures patients with severe osteoporosis, a weekly teriparatide can promote the union of fractures, prevent further collapse of the vertebral body, and reduce the back pain faster.