• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.20 no.4
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• pp.484-489
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• 2011

Nowadays, the automobile manufactures make a great efforts to reduce manufacturing cost, body weight and to develop eco-environmental parts in order to be more competitive and solve global warming. For these reasons, materials of automobile's parts are changed over from general carbon steel and stainless steel to plastic and Aluminum. And, laser welding technology is introduced to apply welding between aluminum parts. In this paper, the data of laser welding parameters is collected through lots of the experiment according to the material, welding speed and laser power to apply laser welding in Aluminum fuel filler neck assembly. After manufacturing prototype of aluminum fuel filler neck, vibration durability test, tensile strength test and salt water test are applied to verify product's satisfied function.

• Journal of architectural history
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• v.14 no.3 s.43
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• pp.39-52
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• 2005

This study relates to the architectural planning principle of Gyeonghoeru pavilion, one of the major buildings in Gyeongbokgung palace. The study is concentrated on The Book of Gyeonghoeru Pavilion written by Jeong Haksun in 1865 during the reconstruction of Gyeonghoeru pavilion. The architectural planning principle of Gyeonghoeru pavilion disclosed in The Book of Gyeonghoeru Pavilion appears to be 'the method of expanding with six by six system'. 'The method of expanding with six by six system' means a way of continuously extending the number related to 6 by addition, subtraction, multiplication and division, and reflecting to architecture, having number 6 as the basic number. Number 6 means a large amount of water in East Asian philosophy, Applying 'the method of expanding with six by six system' to the architecture of Gyeonghoeru includes an intention to prevent fire in a way of a type of incantation because Korean traditional wooden buildings are we to fire. Since Gyeonghoeru is surrounded by a pond and was constructed based on the number 6 having a strength of water, it was believed that it could be safe from fire. This study compares the contents disclosed in The Book of Gyeonghoeru Pavilion with the construction of Gyeonghoeru to find out how the number 6 was applied to the overall construction of Gyeonghoeru. From the fact that the total number of km of Gyeonghoeru is 36 ($6{\times}6$), the number of pillars is 42 ($6{\times}7$), and the number of windows and doors is multiples of 6, it has been found out that the number 6 is deeply related to the overall construction of Gyeonghoeru. In addition to the fact that the construction of Gyeonghoeru can be explained by 'the method of expanding with six by six system', The Book of Gyeonghoeru Pavilion also discloses parts where Diagram of Hotu, Later Heaven Arrangement and Arrangement of 64 Hexagrams are applied. Therefrom, it has been found out that Gyeonghoeru pavilion was constructed by applying the principles of East Asian philosophy based on The Book of Changes.

• Proceedings of the Korean Society for Information Management Conference
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• 2018.08a
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• pp.51-54
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• 2018

본 연구는 문헌정보학 학술지 논문의 결론 장(chapter)의 특색을 분석하기 위하여 결론의 분석도구를 개발하고, 결론의 구조와 경향성을 파악하는데 있다. 연구 결과, 문정학 학술지 논문의 결론 장은 평균 4.2개의 구성요소로 구성되었다. 결론 제목은 '결론'이 절반 이상이며, 그 다음은 '결론 및 제언' 이었다. 각 구성요소별 출현빈도는 '연구결과 요약'이 단연 우세하며, '연구전체 요약', '후속연구 제언', '연구 의의' 순이었다. 서술 분량은 '연구결과 요약'이 가장 우세하며, 결론의 절반 이상을 차지하였다. 결론을 시작하는 첫 번째 요소로 가장 우세한 요소는 '연구결과 요약'이며, 결론을 마무리하는 최종 요소로 가장 우세한 것은 '후속연구 제언'이었다. 문헌정보학 학술지 논문 결론 구조의 핵심 구성요소이자 핵심기능은 '요약하기'의 구성요소인 '연구결과 요약'과 '연구전체 과정 요약'이다. 이는 결론을 기술하는데 필수 요소로 밝혀졌다. '적용하기','확대하기'에 포함된 여타의 요인은 선별적 요인으로 적용하고 있었다.

• Resources Recycling
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• v.28 no.1
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• pp.62-72
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• 2019

Generally, $H_2SO_4$ and Cu metal are used as raw materials for producing copper sulfate. The study relates to a method for producing copper sulfate using electrowinning from a waste solution of copper chloride. Uses are used for copper plating for industry, plating, feed, agriculture, electronic grade PCB. Conventional methods for producing copper sulfate have a problem of a large amount of waste water and a high energy cost. A study on the production method of copper sulfate ($CuSO_4$), which is the most used among copper (Cu) compounds, has a low process operation ratio, a small amount of waste water, and a simple manufacturing process. It is easy to remove Na, Ca, Mg, and Al as impurities by using a cationic membrane. At the same time, high purity copper powder could be recovered by an electrowinninng method. Using the recovered copper powder, high purity copper sulfate could be produced.

• Journal of the Korean Society of Physical Medicine
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• v.4 no.2
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• pp.117-124
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• 2009

Purpose：The purpose of this study was to investigate of the change of the forward head posture(FHP) according to computer using time. Methods：Subjects were 30 male and 30 female. The factors of FHP were measured cranial vertical angle, cranial rotation angle, and head, upper back, neck flexion/extension angle according to computer using time. Change of FHP used to Digital Inclinometry(JTech, Dualer IQTM Dual Inclinometer). The data were collected by data logger(Logger Teknologi HB, Akarp, Sweden). Results：Cranial vertical angle, cranial rotation angle, and head, upper back, neck flexion/extension were increased according to computer using time(p<.05). But cranial vertical angle and cranial rotation angle, and head, upper back, neck flexion/extension were not significant differences between male and female group(p>.05). Conclusion：The effects of cranial vertical angle, cranial rotation angl and head, neck and upper back angle depend on the computer task time. Increased of FHP may result increased tension in posture muscles of cervical spine, resulting in a risk of musculoskeletal disorders.

• Journal of the Korean GEO-environmental Society
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• v.15 no.12
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• pp.61-69
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• 2014

Carboxymethyl-${\beta}$-cyclodextrin (${\beta}$-CMCD), as a biodegradable surfactant with hydrophobic and hydrophilic properties, has potential advantages of being applicable to the simultaneous treatment of multiple contaminated soils. In this study, the desorption behaviors of r adionuclides such as cobalt (Co), strontium (Sr), and cesium (Cs) from the soil contaminated with them were experimentally investigated and the effectiveness of CMCD as a desorbent was evaluated. The desorption equilibrium of used radionuclides could be achieved within 1~3 hr and the desorption ratio from kaolin was higher than that from natural soil. The addition of CMCD of 2 g/L increased the desorption ratio by 5~20 % and the desorption ratio of used r adionuclides was shown in the order of Co > Cs > Sr. The experimental desorption data were fitted successfully by pseudo-second order kinetic model and the desorption rate of the r adionuclides was shown in the order of Cs > Co > Sr. Hysteresis between adsorption and desorption of the r adionuclides, as shown in the order of Sr > Co > Cs, increased as the desorption rate decreased. Consequently, it could be considered that the desorption rate was one of the significant factors of the hysteresis. The addition of CMCD as desorbent increased the amount of desorbed radionuclides and decreased the hysteresis. However, the CMCD could not completely desorb the radionuclides from soils even though the excess of CMCD was added.

• Journal of Embryo Transfer
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• v.23 no.3
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• pp.133-139
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• 2008

DNA methylation is one of the reasons for poor survival of clone animals. The OCT-4 gene is essential for maintaining pluripotency of embryonic stem (ES) cells and early embryos. We previously reported that the 5'-promoter region of Oct-4 gene was a target of DNA methylation and the methylation status was changed variously during embryonic development in bovine. The study conducted to examine the expression and methylation pattern of tissue-dependent differentially methylated region (T-DMR) of Oct-4 gene in bovine somatic cell nuclear transfer (SCNT) and in vitro fertilization (IVF) blastocysts. The Oct-4 gene expression was evaluated by RT-PCR and fluorescence immunocytochemistry. The methylation pattern of T-DMR was analyzed using restriction mapping and bisulfite sequencing methods. The Oct-4 transcripts were highly expressed in IVF, while they were not expressed in SCNT. The Oct-4 protein was not detected or expressed at very low level in SCNT, the intensity of Oct-4 protein, however, was strong in IVF. On the other hand, the T-DMR of Oct-4 gene was hypermethylated in SCNT compared to that of IVF. These results suggested that expression and the failure of demethylation of Oct-4 gene was closely associated with incomplete development of SCNT embryos.

• Korean Journal of Agricultural and Forest Meteorology
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• v.19 no.3
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• pp.195-202
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• 2017

This study aims to suggest the basics for the implementation of the farmstead-specific early warning system (FEWS) for weather risk management nationwide. A survey by questionnaire was conducted to examine farmer's response, and a cost-benefit analysis was made to examine the effect of the FEWS on the economy. The farmers who volunteered to participate in this survey responded that they were generally satisfied with the FEWS, and that they used it well for farming. Willingness to pay (WTP) for the early warning service was estimated to be 8,833 KRW per month by survey respondents. If the early warning service is extended to nationwide and 50% of farmers use it for six months, then the ratio of benefit to cost will be 2.2, indicating that nationwide expansion of the FEWS is very feasible.

• Journal of Embryo Transfer
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• v.31 no.3
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• pp.161-168
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• 2016

Nucleotide metabolism in endothelium is variable between different species. Recent studies demonstrated that this variability could contribute coagulation dysfunction, even though organs of the alpha 1,3-galactosyltransferase gene knockout pig were transplanted into the primate. CD73 (ecto-5'-nucelotidase) is an enzyme at cell surface catalyzing the hydrolysis of adenosine triphosphate to adenosine, which plays role on a substance for anti-inflammatory and anti-coagulant. Thus, overexpression of CD73 in endothelial cells of the pig is considered as an approach to reduce coagulopathy. In this study, we constructed a human CD73 expression vector under control of porcine Icam2 promoter (pIcam2-hCD73), which is expressed specifically at endothelial cells, and of CMV promoter as a control (CMV-CD73). First, we transfected the CMV-CD73 vector into HEK293 cells, and then confirmed CD73 expression at cell surface by flow cytometry analysis. Next, we transfected the pIcma2-CD73 and CMV-CD73 vectors into primary porcine fibroblasts and endothelial cells. Consequence was that the pIcma2-CD73 vector was expressed only at the porcine endothelial cells, meaning that the pIcam2 promoter lead to endothelial cell-specific expression of CD73 in vitro. Finally, we nucleofected the pIcam2-hCD73 vector into passage 3 fibroblasts, and enforced hygromycin selection of 400mg/ml. We were able to obtain forty three colonies harboring pIcam2-CD73 to provide donor cells for transgenic cloned porcine production.

• The Korean Journal of Mycology
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• v.20 no.1
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• pp.1-10
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• 1992

Fresh fungi were collected during field trips to Ullung Island from August, 1990, to September, 1991. Among them, some polyporoid fungi were recognized to the species. Thirty three species were identified, among which nine fungi were confirmed new in Korea and registered here with descriptions. These fungi are Auriporia aurulenta, Ceriporiopsis gilvescens, Ceriporiopsis subvermispora, Gloeophyllum trabeum, Junghuhnia separabilima, Oligoporus stipticus, Oxyporus similis, Phellinus lavigatus, and Polyporus melanopus.