• Proceedings of the KIPE Conference
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• 2005.07a
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• pp.179-181
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• 2005

PWM(Pulse Width Modulation) 컨버터에서 공급 전압의 품질은 교류 입력전류 및 직류 출력전압의 품질에 큰 영향을 미친다. 공급전압이 불평형 또는 고조파가 포함된 경우에는 평형 전원전압의 경우보다 입력 전류의고조파 및 역률 특성이 저하된다. 또한 컨버터 입력 측의 사용된 인덕턴스의 용량에 따라 입력전류의 고조파 및 역률 특성이 달라진다. 본 논문에서는 입력측 인덕턴스 값의 변화에 따른 단상 및 삼상 PWM 컨버터의 입력전류 고조파와 역률 관계를 해석하였는데, 특히 입력전압에 고조파를 포함한 경우와 불평형인 상태까지 확장하여 성능을 평가하였다. 이러한 결과를 통해 입력 인덕턴스 설계 값을 선정하는데 기준을 제시하였다.

• Korean Journal of Medicinal Crop Science
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• v.7 no.3
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• pp.177-184
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• 1999

This study was carried out to find growth characters and distribution of above and underground in natural crossed population of Paeonia lactiflora Pallas. Sprouting time was 1 April to 15 April, and distribution of stem length ranged from 21 to 80cm, and 3 to 18 in stem number. Distribution of root length ranged from 12 to 59cm, root number per plant was 73 to 4, root yield per plant was highly varied by 37 to 882g, and larger root above 750g was occupied by 7.1%. Paeoniflorin content was 1.9 to 10.29% and plants containing higher paeoniflorin was 14.3%. Root length and yield had highly positive correlation. Root diameter and stem length was also positively correlated.

• Magazine of the Korea Concrete Institute
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• v.10 no.6
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• pp.169-178
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• 1998

Bond strength of reinforcing bar to high-perfomance concrete using belite cement is explored using beam end test specimens. The key parameters for the bond test are slump of concrete, top bar effect, and strength of concrete in addition to concrete cover. The test results show that the specimens with belite cement concrete show approximately 10% higer bond strength than those with portland cement concrete. The results also show that the bond strength from the high strength concrete is function of the square root of concrete compressive strength. Bond strength of the top bar is less than bond strength of bottom bar, but the ratios of the bond strength of bottom-cast bars to those for top-cast bars are much less than the modification factor for top reinforcement found in the ACI 318-95 code. Comparisons with other reported tests identified that belite cement increased bond strength while silica fume or flyash used in high strength concrete decreased bond strength. The high-strength and high-slump concrete with belite cement performs well in terms of bond strength to reinforcing steel.

• Journal of the Korean Society of Costume
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• v.58 no.7
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• pp.60-75
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• 2008

A history of Chinese Costume is that of the accept and the struggle between the 'Shen- Yi' of Han(漢) race and 'Ho-Bok' of foreign races. There are the 'Shen-Yi Ko' and the 'Ho-Bok Ko' in their representative documentary. They are quite significant materials for the researchers of the Oriental costume. The purpose of this study about comparing and analyzing the 'Shen-Yi Ko' and the 'Ho-Bok Ko' give a guidance to Chinese costume's researchers. The results of study are as follows: The 'Shen-Yi', having made a dress joined an upper to the low clothing together(上衣下裳) and deeply covered the parts of all the bodies, was named, had appeared the Spring-Autumn & warring state period(春秋戰國時代) and later the former Han Dynasty(前漢). Not only everyone in spite of men and women, without distinction of rank, high and low alike but also even the court dress(朝服) and from latter Han Dynasty(後漢) only the housewives could have worn it. The 'Shen- Yi Ko' disappeared its records and remains and at present nothing leave behind. The 'Ho-Bok' is a costume of the nomadic horse-riding people among the foreign races, then influenced upon the Chinese costume. The style of the Chinese costume consists of 'Yi Sang'(衣裳) and the 'Ho-bok' of foreign races, 'Yi Ko'(衣袴). The 'Yi Ko'((衣袴), derived from the King Muryoung of Cho Dynasty, had greatly been changed the chinese men's clothing and After that 'Ko Sup'(袴褶). The Chinese have enjoyably and familiarly the accepted 'Ho Bok' for a long time.

• Radiation Oncology Journal
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• v.4 no.1
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• pp.75-80
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• 1986

Heterotopic bone formation is a complication which occurs in 0.6 to $61.7\%$ of patients after total hip replacement arthroplasty. We reviewed 4 patients (8 hips) who received postoperative irradiation on their hi ps for prevention of heterotopic bone formation in the Department of Therapeutic of Therapeutic Radiology, Seoul National University versify Hospital from January 1981 through August 1985. Radiation therapy was started 6 to 10 days postoperatively with the dosage of 2,000 cGy given in 10 fractions. As a result, 7 hips had Grade 0 and 1 hip had Grade 1 heterotopic ossification according to modified Blocker system. Our result and review of the literatures strongly support that the postoperative radiotherapy is effective for prevention of heterotopic bone formation in high risk group.

• Journal for History of Mathematics
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• v.24 no.1
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• pp.1-13
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• 2011

In Tian mu bi lei cheng chu jie fa(田畝比類乘除捷法) of Yang Hui suan fa(楊輝算法)), Yang Hui annotated detailed comments on the method to find roots of quadratic equations given by Liu Yi in his Yi gu gen yuan(議古根源) which gave a great influence on Chosun Mathematics. In this paper, we show that 'Zeng cheng kai fang fa'(增乘開方法) evolved from a process of binomial expansions of $(y+{\alpha})^n$ which is independent from the synthetic divisions. We also show that extending the results given by Liu Yi-Yang Hui and those in Suan xue qi meng(算學啓蒙), Chosun mathematican Hong Jung Ha(洪正夏) elucidated perfectly the 'Zeng cheng kai fang fa' as the present synthetic divisions in his Gu il jib(九一集).

• Journal of Korean Classical Literature and Education
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• no.34
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• pp.115-147
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• 2017

This paper compared and reviewed the poetic theories and Chinese poems of the Korean author Kim Chang Heup and his Japanese counterpart, Kan Chazan. Kim Chang Heup and Kan Chazan shared largely the same opinions on poetry, and both rejected archaism. First, they did not just copy High Tang poetry. Instead, they focused on the (sometimes trivial) scenery right in front of them, and described the calm feelings evoked by what they had seen. They also adopted a sincere tone, instead of an exaggerated one, because both believed that poetry should be realistic. However the differences between the two poets are also noteworthy. Kim Chang Heup claimed that feelings and scenery meet each other within a literary work through Natural Law, and the linguistic expressions that mediate the two are philosophical in nature. However, Kan Chazan did not use Natural Law as a medium between feelings and scenery. Instead the Japanese writer said the ideal poetical composition comes from a close observation and detailed description of scenery. In sum, while Kim Chang Heup continued to express reason through scenery, Kan Chazan did not go further than depicting the scenery itself. In addition, Kim Chang Heup believed poetry was not only a representation of Natural Law, but also a high-level linguistic activity that conveys a poetic concern about national politics. As a sadaebu (scholar-gentry), he held literature in high esteem because he thought that literature could achieve important outcomes. On the other hand, Kan Chazan regarded it as a form of entertainment, thereby insisting literature had its own territory that is separate from that of philosophy or politics. In other words, whereas Kim Chang Heup considered literature as something close to a form of learning, Kan Chazan viewed it as art. One might wonder whether the poetics of Kim Chang Heup and Kan Chazan reflect their individual accomplishments, or if the characteristics of Chinese poetry that Korean and Japanese poets had long sought after had finally surfaced in these two writers. This paper argued that the two authors' poetics represent characteristics of Chinese poetry in Korea and Japan, or general characteristics of Korean and Japanese literatures in a wider sense. Their request to depict actual scenery in a unique way, free from the ideal model of literature, must have facilitated an outward materialization of Korean and Japanese literary characteristics that had developed over a long time.

• Journal of Animal Environmental Science
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• v.7 no.3
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• pp.155-164
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• 2001

Environmental factors such as $NH_3,\;H_2S,\;CO_2$, dust, temperature, and humidity in the animal house are a potential health hazard to humans and animals. Until now, most of measurement methods can only provide periodic results with low accuracy. A data acquisition system which can measure continuously and simultaneously $NH_3,\;H_2S,\;CO_2$, temperature, and humidity was developed and installed in two pig houses. Daily changes of environment for the pig-houses were investigated by the data acquisition system. In order to evaluate NH$_3$sensor, gas samples were obtained and NH$_3$concentrations were measured at nine positions; combinations of three positions(inlet, middle, and outlet) and three heights(0 cm, 40 cm, 150 cm). Ammonia concentration of 14.0 ~37.1 ppm for slurry pig-house is higher than that of 8.4~29.7 ppm for scraper pig-house, and there were no statistical differences among the positions. However, the concentration of $NH_3$at 150 cm was higher than thats of 0 cm and 40 cm.

• Korean Journal of Heritage: History & Science
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• v.46 no.1
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• pp.102-123
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• 2013

This paper is a study about the Gang Sehwang's (姜世晃 1713~1791) Ink Orchid Painting. Gang Sehwang is a representative literati gentleman who painted Four Gentlemen, for the first time, during the late Joseon Dynasty. There are 20 pieces of Ink Orchid Painting of his in Korea. His recognition of the Ink Orchid Painting can be understood through his records and analysis of his Ink Orchid Painting. He considered the sketch from the nature (寫生), practice of old paintings (古畵), and copy-training of the manual of paintings (畵譜). Particularly, Gang Sehwang focused on the copy-training of old paintings (古畵臨倣) which integrates the will and spirit of old literati gentlemen. This means that he had recognized the picture as a means of 'literature carrying morality (載道). Also, we could read self-discipline (修己的) values from his continuative copy-training of the manual of paintings (畵譜臨倣). Next, his Ink Orchid Painting were divided into the first half of the term (his 30s to 40s) and the second half of the term (his 60s to 78 years old). He had polished up on the Jieziyuanhuazhan ("芥子園畵傳") during the first half of the term and on the Shizhuzhaishuhuapu ("十竹齋書畵譜") or the Maejuknanguksabo ("梅竹蘭菊四譜") during the second half of the term. Therefore, it could be understood that he had depended on the manual of paintings (畵譜) for a long time. Nevertheless, he had completed the elegant and graceful Pyeoam Orchid (豹菴蘭)' based on his skill of the manual of paintings (畵譜) in his 70s. Finally, the 18th century Ink Orchid Painting and painters who lived (worked) at that time were investigated. He made?? the Albums of Calligraphy and Painting (書畵合壁帖) with Shim Sajeong (沈師正) and Choi Buk (崔北). They also interacted with each other by Calligraphy and Painting (書畵). Also, Yi Insang (李麟祥) and Im Heeji (林熙之) contributed to the diversification of the 18th century Ink Orchid Painting style by imitating Ink Orchid Painting with the manual of paintings (畵譜). Moreover, it is meaningful that the Ink Orchid Painting of Gang Se-hwang and the18th century Ink Orchid painters influenced the foundation of the 19th century Ink Orchid Painting fashion.