• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.3
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• pp.252-262
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• 2019

Following the earthquake in Gyeongju (2016) and Pohang (2017), South Korea is no longer a safe place for earthquakes. Accordingly, the need for shelters suitable for disaster environments is increasing. In this study, a lightweight composite panel was used to produce post-disaster housing for refugees to compensate for the disadvantages of existing evacuation facilities. For this purpose, an evaluation of structural performance and thermal environment for post-disaster housing for refugees composed of lightweight composite panels was performed. To assess the structural performance, a lateral loading test was conducted on a system made of lightweight composite panels. The specimens consisted of two types, which differed according to the bonding method, as a variable. In addition, the seismic and wind loads were calculated in accordance with KBC 2016 and compared with the experimental results. Regarding the energy performance, optimization of south-facing window planning and window-wall ratio and solar heat gain coefficient were analyzed to minimize heating, cooling, and lighting energy. As a result, the specimens composed of lightweight composite panels will perform sufficiently safely for lateral loads and the optimized window planning will lead to a low-energy operation.

• Journal of the Korean Chemical Society
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• v.63 no.2
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• pp.102-110
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• 2019

The purpose of this study was to explore the progression levels of science metamodeling knowledge through using questionnaires for 97 students of the gifted in G science academy. As a result of the Rasch model analysis, it was confirmed that the progression levels of the scientific metamodeling knowledge is suitable for the person reliability of 0.71 and the item reliability of 0.96. The progression levels of students' science metamodeling knowledge were classified into 4 stages. First and second levels were considered model to be objective and the third and fourth stages were perceived as subjective. The first level is to view the model as a visual representation of a phenomenon as it is, and the second level is to think that the model corresponds to objective knowledge or theory and is a tool for explanation. The Third level looks at the model as a scientist's exploration tool and fourth level is to think that the model is provisional one and multiple models can coexist in one phenomenon. The progression levels of science metamodeling knowledge of science high school students derived from this study is expected to be used as a reference when constructing a curriculum for science modeling and modeling for gifted students.

• Journal of Conservation Science
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• v.34 no.6
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• pp.517-524
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• 2018

This study using a method different from those employed previously, the anatomical characteristics of paper-mulberry wood were confirmed by observing three different sections. In addition, the factors affecting the pulp and papermaking processes were analyzed in terms of morphological properties such as the fiber length and width, lumen width, and chemical composition of the paper-mulberry bast fiber. The anatomical characteristics of the paper-mulberry wood were a ring porous or semi-ring porous structure with the vessels showing solitary pore and radial array. The medullary ray of the tangential section showed 1-3 rows and common helical thickening. Consequently, the paper-mulberry wood has the same anatomical characteristics throughout. The morphological characteristics of the paper-mulberry bast fiber are a fiber length of 6.58 to 9.01 mm, fiber width of 15.85 to $27.80{\mu}m$, lumen width of 4.50 to $12.54{\mu}m$. The D sample of Gangwon was the most suitable for the pulp and papermaking processes, in terms of its derived morphological ratios. Comparing the chemical compositions, the C sample of Gyeongsang had a high holocellulose content (90%). Thus, the findings herein will aid in determining the quality of Korean paper post production.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.11
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• pp.8-17
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• 2018

A large urban region in Bangkok, Thailand is often inundated due to shallow water floods along the paved roads that have poor drainage facilities, and that can cause urban flooding. Existing methods, including using sand bags are not effective to prevent flooding in urban areas where the amount of sand is not sufficient. Thus, it is necessary to install artificial flood defense structures. However flooding and overflow defense equipment, which was developed in some advanced nations in Europe and in the USA, is highly expensive and complex construction methods are needed, therefore they are not suitable to be used in Southeast Asia. Thus, it is necessary to develop a flood rapid defense system(FRDS), which is inexpensive and simple to build, but is also highly functional. Thus, this study developed an FRDS that can be applied to Southeast Asia through the careful study of FRDS overviews, an analysis on the development trends in Korea and overseas, and the proposal of development needs and directions of the region. For the system developed, Korean Standards(KS) performance evaluations on leakage ratio deformation tests and impact resistance tests were conducted at the Outdoor Demonstration Test Center(Seosan) in the Korea Conformity Laboratories(KCL) and the system satisfied the standards of KS F 2639(leakage and deformation test) and KS F 2236(impact resistance test). The present study results can not only be applied to urban floods in Southeast Asian nations to cope with flood-related disasters, but also be utilized in flood prone regions and for major facilities in Korea. They can also induce scientific and pro-active responses from major local governments and facility management organizations in relation to urban floods.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.11
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• pp.561-567
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• 2018

This study was carried out to improve the ride quality of high-speed electric multiple unit. Through dynamic analysis of the HEMU-430X, the range of the equivalent conicity with a critical speed of 300 km/h was between 0.05 and 0.25. The initial adopted wheel profile of HEMU-430X was S1002. The equivalent conicity of S1002 with the mileage of more than 40,000 km was about 0.033 and it was confirmed that XP55 is more suitable for stable operation because XP55 has the equivalent conicity of over 0.061. In order to improve ride quality of high-speed electric multiple unit, the change of installation angle of the yaw damper was suggested from $7.35^{\circ}$ to $0^{\circ}$. From sensitivity analysis and optimization, the air spring lateral and vertical stiffness was suggested to be reduced by 30% and the secondary vertical and lateral damper damping coefficient was increased by 50%. By applying this, it was expected that the car body acceleration could be improved by about 20% on average. The HEMU-430X's yaw damper installation angle was changed to $0^{\circ}$ and the damping coefficient of the lateral damper was increased by 30%. When the test run was carried out at the speed of 300 km/h on the Kyungbu high-speed line, the vehicle lateral acceleration had improved by 34.3%. The effect of additional improvement measures proposed in this paper will be tested in the on track test. The riding quality improvement process used in this study can be used to solve ride quality problems that can occur in commercial operation of high-speed electric multiple unit in the future.

• Journal of the korean academy of Pediatric Dentistry
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• v.46 no.3
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• pp.265-273
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• 2019

This study was performed to evaluate clinical use of laser fluorescence (LF) to identify early childhood caries lesions suitable for applying resin infiltration. 20 exfoliated primary molars with proximal caries were selected and cut buccolingually cross the central pit for regarding the mesial and distal surfaces respectively. 27 specimens corresponding to ICDAS code 1 and 2 were selected and the LF values were measured. When infiltrant resin was applied, double staining for microscopy detection has done simultaneously. Tooth samples were sliced with 0.7 mm thick. The maximum lesion depth, maximum penetration depth, and average penetration rate were measured from the confocal scanning laser microscope image. Pearson correlation analysis was performed. The intraclass correlation coefficient of LF values shows excellent agreement. LF values had positive correlation with penetration rate, but not lesion depth and penetration depth. Significant correlation between LF readings and penetration rate was verified in deep enamel caries and dentin caries except shallow enamel caries. Infiltrant resin could penetrate with a higher rate and LF values could be increased in more active caries lesions. In assessing radiologically similar caries lesion, laser fluorescence might be useful for identifying caries activity.

• Journal of the Korean Institute of Landscape Architecture
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• v.47 no.3
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• pp.49-59
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• 2019

This paper examines the background and content of Thomas Jefferson's botanical garden plan for the University of Virginia. When Jefferson promoted the establishment of a botanical garden, European botanical gardens were evolving from physic gardens, and American botanical gardens were in their infancy. Accordingly, this paper compares the Botanical Garden Plan for the University of Virginia with contemporary botanical gardens. This is examined by outlining the trends of botanical gardens in Europe and the United States around the nineteenth century, analyzing their function and spatial structure. Also, Jefferson's perspective on botany, his plan, and botanical gardens are reviewed. This study found that Jefferson's project had its background in the social recognition of the importance of botany as a practical science, advancing the national economy, which was a prominent goal in late eighteenth-century Europe, and in developing networks of exchanging plants and information concerning botany and botanical gardens. Based on the botanist Correia's opinion on the role of a public botanical garden, the Botanical Garden Plan for the University of Virginia was developed by Jefferson as an action plan, including its site creation, space organization, and supplying of plants. Compared to the other contemporary botanical gardens, the University of Virginia's Botanical Garden Plan has the following characteristics. First, like European gardens in the late eighteenth century, it evolved from being a physic garden to a botanical one. As such, it emphasized botanical research and education over medicine, creating a tree garden and a plant garden. Second, it differed from many European and American botanical gardens in that it rejected decorative elements, refused to install a greenhouse, and attempted to spread practical overseas plants suitable to the local climate. This study contributes to broadening the history of botanical gardens at the turn of the nineteenth century.

• Journal of the Korean Institute of Gas
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• v.23 no.3
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• pp.20-26
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• 2019

Selective catalytic reduction(SCR) method is widely used among various methods for reducing nitrogen oxides in combustion devices of coal power plant. In the present study, the computational fluid dynamic analysis was accomplished to derive the optimal shape of ammonia-dilution air mixing device in a ammonia injection grid. The distribution characteristics of flow and $NH_3$ concentration had been elucidated for the reference shape of ammonia mixing device(Case 1). In the mixing device of Case 1, it could be seen that $NH_3$ distribution was shifted to the wall opposite to the inlet of the ammonia injection pipe. For the improvement of $NH_3$ distribution, the case(Case 2) with closing one upper injection hole and 4 side injection holes, the case(Case 3) with installing horizontal plate at the upper of ammonia injection pipe, the case(Case 4) with installing horizontal plate and horizontal arc plate at he upper of ammonia injection pipe were investigated by analyzing flow and $NH_3$ concentration distributions. From the present study, it was found that the % RMS of $NH_3$ for Case 4 was 4.92%, which was the smallest value among four cases, and the range of $R_{NH3}$ also has the optimally uniform distribution, -10.82~8.34%.

• Journal of Hospice and Palliative Care
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• v.22 no.3
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• pp.134-143
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• 2019

Purpose: This methodological study was conducted to test the reliability and validity of an instrument that measures attitudes of advance directives (ADs) among nurses. Methods: 1) Sixteen items related to attitudes in the English version of the Knowledge, Attitudinal, and Experiential Survey on Advance Directives (KAESAD) were forward/backward translated into Korean. 2) The content was validated by an expert panel (three nursing professors and eight hospice nursing specialists). 3) The preliminary 12 items were selected as a tool to assess the Korean version of Nurses' Attitudes towards Advance Directives (NAAD-K). 4) The instrument was validated by a survey (n=216). 5) It was confirmed to use the 12 items for the final version of the instrument. Results: NAAD-K was shown to be valid in terms of factors, items and content. The three factors extracted from the factor analysis were named as follows: Caring for patients with an AD (factor 1), nurses' role in informing patients (factor 2) and patient right (factor 3). The three factors explained total variance 57.796%. Factor loadings of the 12 items ranged from 0.47 to 0.93. For the 12 items, Cronbach's alpha was 0.81, and Guttman split-half coefficient was 0.78. Conclusion: This instrument was identified to be applicable with satisfactory reliability and validity for further use in measuring nurses' attitudes towards ADs in hospice and palliative care.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2019.04a
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• pp.87-87
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• 2019

현대인의 생활수준의 향상에 따른 관상식물의 관심이 증가하여, 자생초화류를 활용하기 위한 연구가 진행되고 있다. 산꼬리풀[Veronica rotunda var. subintegra (Nakai) T.Yamaz.]은 국내 특산식물로서 산지의 초원에서 자생하고, 쪽빛을 내는 화기는 청아한 느낌을 주어 관화식물로서 이용가능성이 높다. 본 연구는 산꼬리풀의 분화 재배기술을 확립하고자 2018년 7월 2일부터 10월 15일까지 수행하였다. 대조구는 플라스틱 화분 10호에 원예상토를 충진한 다음 200구에 셀당 4립 파종하여 생산된 유묘를 정식하였다. 실험은 식재용기(플라스틱 8, 10, 12호 화분, 비닐포트 3, 4치), 토양종류[원예상토 단용, 중화 피트모스:펄라이트(3:1, 4:1), 마사토:중화 피트모스(2:1, 3:1)], 묘의 소질[파종립수(1, 2, 4, 6립), 파종용기(162, 200, 288구 트레이)] 등이 생육에 미치는 영향을 분석하였다. 연구의 결과, 식재용기에 따른 생육은 플라스틱 화분 12호에서 왕성하였고, 포트의 용적량이 클수록 경직경, 측지수, 마디수, 엽수, 개화율이 유의적으로 증가하였다. 토양종류에 따른 생육은 원예상토에서 가장 왕성하였고, 측지수, 경직경, 마디수, 엽수 및 개화율이 모두 우수하여 관상용 재배에 적합하였다. 피트모스 혼용토는 생육이 억제되는 동시에 잎이 황화되는 현상이 나타났다. 마사토 혼용토의 경우, 생육이 억제되는 결과를 보였다. 셀당 파종량을 달리한 유묘를 정식하여 재배한 결과, 초장, 절간장은 파종량이 증가할수록 감소하였고, 포트당 마디수와 엽수는 증가하였으나, 1립 파종묘를 제외하고 유의적인 차이는 없었다. 개화율은 4립 파종묘(44.4%)가 1, 2, 6립 파종묘(20.8~25.0%)보다 높았다. 육묘용기별 생육은 초기생육이 우수하였던 162구 생산묘가 정식 후 재배에도 왕성한 생육을 나타내었다. 결론적으로, 산꼬리풀의 최적의 분화재배를 위해 플라스틱 화분 12호에 원예상토를 충진한 다음 162구 트레이에 포트당 엽수와 개화율이 높은 4립 파종하여 생산된 유묘를 정식하여 재배하는 것이 우수할 것으로 판단된다. 경제적 측면을 고려하여 토양은 비교적 생육이 양호하였던 마사토의 활용방안을 검토하는 것이 좋을 것으로 생각된다.