• Title/Summary/Keyword: 구경

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Growth and Bulb Characteristics of Extremely Early-Maturing Onion by Air Temperature Variation at Different Altitudes (해발고도별 기온변화에 따른 극조생 양파의 생육 및 구특성)

  • Song, Eun Young;Moon, Kyung Hwan;Wi, Seung Hwan;Oh, Soonja
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.20 no.4
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    • pp.321-329
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    • 2018
  • A study was carried out to determine the influence of climatic environments on the growth characteristics and bulb quality of extremely early-maturing type onion grown at different altitudes, such as 60m, 200m, 350m and 700m above sea level (ASL). The mean air temperature during the growing season of extremely early-maturing type onion (October 18 to April 27) was $10.8^{\circ}C$, $9.6^{\circ}C$, $8.1^{\circ}C$ and $6.1^{\circ}C$ at 60m, 200m, 350m and 700m ASL. The mean air temperature during the bulb growth period (March 16 to April 14) was recorded $10.5^{\circ}C$, $9.4^{\circ}C$, $7.9^{\circ}C$ and $6.0^{\circ}C$ at 60m, 200m, 350m and 700 m ASL. Plant height, neck diameter, leaf number, leaf area, top fresh weight and top dry weight were significantly increased in growing of extremely early-maturing type onion at 60m ASL. Bulb/neck diameter ratio increased rapidly under the same temperature regime. The diameter and weight of the bulb were also the largest at 60m ASL during the bulb growth period (daily mean temperature of $12.5^{\circ}C$). At 60m ASL, there was the highest bulb size like a height, diameter and weight of bulb related directly on onion yield in the bulb growth period from March 16 to April 14. In contrast, yield and bulb quality were considerably decreased at 700m ASL during the bulb growth stage (daily mean temperature of $8.4^{\circ}C$). The quantity of extremely early-maturing type onion has gradually decreased as the daily average temperature drops below $12.5^{\circ}C$ during the bulb growth stage (March 16 to April 14). As a result, the lower temperature (daily mean temperature below $12.5^{\circ}C$) during the bulb growth stage significantly decreased the size and quantity of bulb in direction proportion.

A Review of Ecological Niche Theory from the Early 1900s to the Present (생태적 지위(Ecological Niche) 이론에 대한 검토 및 제언)

  • Koo, Kyung Ah;Park, Seon-Uk
    • Korean Journal of Environment and Ecology
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    • v.35 no.4
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    • pp.316-335
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    • 2021
  • This study reviewed the change of theory of ecological niche(concepts and definitions) over time to provide a theoretical basis for habitat-related studies of animals and plants. Accordingly, it analyzed and summarized the major discussion trends of ecological niche worldwide in each period from the 1900s to the present. Countries advanced in ecological studies, such as the EU and the USA, have conducted theoretical and empirical studies on the ecological niche since the early 1990s. The concept of the ecological niche was introduced in the early 1900s, developed in the mid-1900s, and advanced from the mid-1900s to the late 1900s. Since the 2000s, the advanced concept has diversified with new developments in technologies and research methods. The factors suggested by theoretical and empirical studies in defining the ecological niche of a species include 1) population dynamics of the target species, 2) all biotic conditions to sustain a population (food relationship and material flow in the food chain), 3) all non-biotic conditions to sustain a population (physical environmental conditions), 4) all direct and indirect interactions between these environmental factors, and 5) response and adaptation mechanisms that include the migratory ability of the target species or genetic diversity and adaptability to change. Unlike such international advancement, there have not been sufficient theoretical, philosophical, and empirical studies of ecological niche in Korea. The concepts and definitions by Greennell, Elton, and Hutchinson were selectively and partially borrowed for empirical studies without full description. Considering that the theory of ecological niche becomes the foundation for habitat-based species conservation and restoration, it is necessary to seek diversification and advancement of theoretical and empirical research and research methods and technological development. It will provide an important foundation for the academic advancement of ecology and for establishing and implementing policies to preserve and restore ecology and biodiversity effectively and successfully in Korea.

Utility and Care Patterns of Lotus Shown in Classic Poetries and Proses, Painting (고전 시문과 회화를 통해 본 연(Nelumbonucifera)의 활용과 애호 행태)

  • Kim, Myung-Hee;Hong, Hyoung-Soon
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.29 no.4
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    • pp.1-13
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    • 2011
  • The purpose of this study is to consider practical examples of the method of utilizing plant material 'lotus' used by the ancients, and the value and meaning they wanted to get from it. The method of this study to do this is descriptive study to consider and interpret poem and painting reflecting impression and concept world of lotus. Summary of this study is as follows. First, ornamental value of lotus could be divided in effect of group plant and detail value held by the flower, the leaves and the stem. Especially, group plant lotus in large site provides unique landscape differentiated form other flowering plants. As well, another feature of lotus is its high ornamental value spread in detail elements including the flower, the leaves, the stem and the lotus seed. Second, fragrance expressed 'Hyang-won-ik-cheong(香遠益淸)' is an important charm of lotus. Lotus was utilized as olfactory element providing fragrance. The ancients considered lotus fragrance not only for enjoy but as symbolic object comparing noble man's dignity so that they expressed it in poem and painting. Third, lotus was utilized as acoustical element. That is, the sound of raindrops harmonizing the surface of water and wide lotus leaves was called 'hearing lotus fond and rain', enjoying it as classic grace. Fourth, summer play lotus sightseeing was called mind wash up meaning 'washing the mind polluted by the mundane world'. Such poetic taste was widely enjoyed by various classes from general public to royal family. Besides, poetic taste related with lotus is the method of drinking alcohol using the feature of big lotus leave and vacant stem, called 'Beog-tong-ju(碧筒酒)'. And in the Joseon dynasty period, when the distinction between the man and the woman influenced by Confucian, lotus seed and 'lotus collecting song' was important sign to express romance between man and woman. Lotus has been enamored by wide classes transcending cultural background as thought and religion since ancient times. Due to such reasons, various symbolic meaning of lotus and planting examples related to religious facilities as temples could not be considered in various manner is limitation of this study, and which is research project for the future.

A Study on the differentiation and development aspects of Zhu-zi xue - centering around the connection between Huang Gan and Jin-hua school in Yuan period (주자학의 사상적 분화와 전개양상에 관한 연구 - 황간(黃?)과 원대(元代) 금화학파(金華學派)의 사상적 연관성을 중심으로 -)

  • Chi, Chun-ho
    • The Journal of Korean Philosophical History
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    • no.23
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    • pp.317-347
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    • 2008
  • Huang Gan(1152 - 1220, pen-name Mian-zhai) was a famous scholar of Zhu-zi xue in the Southern Song period. Zhu-zi xue was also called Daoxue(道學), because it was based on the Cheng-Zhu xue(程朱學) and had very severe idea of Daotong(道統). Therefore, Zhu-zi xue emphasized practical movements of spreading Confucianism. The view of the Daotong(道統) developed in two aspects: protection of Confucianism and exclusion of Daoism Buddhism. Zhu Xi completed the idea of Daotong(道統), and his disciples, especially Huang Gan, continued his efforts. Zhu Xi's disciples searched the ultimate teaching of Confucianism through studying Four-books(四書). In due of their effort, Zhu-zi xue played a reading role in those academic fields. Huang Gan look upon himself as the successor to Zhu-zi xue. He expounded and missionized Zhu Xi's philosophical thought. In his later years, he accepted many students and passed the Zhu Xi's thought on to his students. He fostered "Jin-hua school(金華學派)"-He Ji(何基), the representative of this school. There is the relation of thought on the theory of knowledge and learning centering around Daotong between Huang Gan and Jin-hua school(金華學派). Especially, the most schools leading the academic society of Yuan period founded their thought on Huang Gan's. And it explained Huang Gan's historical influence and contributions to the Zhu-zi xue in the Yuan period.

New material : Classical lyrics novel 'Jeobuin-jeon' (새 자료 가사체 고소설 「져부인젼」에 대하여)

  • YU, KWON SEK;KIM, YOUNG
    • (The)Study of the Eastern Classic
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    • no.70
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    • pp.211-255
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    • 2018
  • A classical lyrics novel 'Jeobuin-jeon' is basically old Korean novel in aspect of contents even though it has lyrics for a song formally. In other words, it shows classic poetry but also expends its genre to novel 'Jeobuin-jeon' which belongs to Jae-yeon Park's selection, presents 'Analects' at a book cover and writes its title inside. In addition, it rewrites the story of 'Jeobuin-jeon' at the beginning that means it is novel. It is considered there might be an unclear reason why it could not be marked as an novel outside. 'Jeobuin-jeon' of Jae-yeon Park's selection helps readers grasp the novel by adding Chinese characters for additional explanation based on Korean characters depending on cases. Used words in this novel is estimated being written from the late $19^{th}$ century to the beginning of the $20^{th}$ century. 'Jeobuin-jeon' is assumed being written by woman as it emphasizes that woman should learn letters and take care of the relationship among parents-in-law, husband, sibling, servant and daughter-law. Besides, this novel intends to punish bad characters through 'Jeobuin's good manners by including afterlife-story with 'Bulddong-Aemi'. 'Jeobuin-jeon''s narration is 7 steps and it reaches the peak when 'Bulddong-Aemi' and 'Jeobuin' changes their life each other. Afterward, 'Jeobuin' meets her parents-in-law and passes the crisis. The story ends through 'Bulddong-Aemi' is punished. It is very creative by developing the story with looking back the past would make a change in narration.

Analysis of Service Factors on the Management Performance of Korea Railroad Corporation - Based on the railroad statistical yearbook data - (한국철도공사 경영성과에 미치는 서비스 요인분석 -철도통계연보 데이터를 대상으로-)

  • Koo, Kyoung-Mo;Seo, Jeong-Tek;Kang, Nak-Jung
    • Journal of Korea Port Economic Association
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    • v.37 no.4
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    • pp.127-144
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    • 2021
  • The purpose of this study is to derive service factors based on the "Rail Statistical Yearbook" data of railroad service providers from 1990 to 2019, and to analyze the effect of the service factors on the operating profit ratio(OPR), a representative management performance variable of railroad transport service providers. In particular, it has academic significance in terms of empirical research to evaluate whether the management innovation of the KoRail has changed in line with the purpose of establishing the corporation by dividing the research period into the first period (1990-2003) and the latter (2004-2019). The contents of this study investigated previous studies on the quality of railway passenger transportation service and analyzed the contents of government presentation data related to the management performance evaluation of the KoRail. As an empirical analysis model, a research model was constructed using OPR as a dependent variable and service factor variables of infrastructure, economy, safety, connectivity, and business diversity as explanatory variables based on the operation and management activity information during the analysis period 30 years. On the results of research analysis, OPR is that the infrastructure factor is improved by structural reform or efficiency improvement. And economic factors are the fact that operating profit ratio improves by reducing costs. The safety factor did not reveal the significant explanatory power of the regression coefficient, but the sign of influence was the same as the prediction. Connectivity factor reveals a influence on differences between first period and latter, but OPR impact direction is changed from negative in before to positive in late. This is an evironment in which connectivity is actually realized in later period. On diversity factor, there is no effect of investment share in subsidiaries and government subsidies on OPR.

A Study on the date of the black glazed bowls with "Gongyu (供御)" or "Jinzhan (進琖)" of Jian ware (건요(建窯) "공어(供御)"·"진잔(進琖)"명흑유완(銘黑釉碗)의 제작시기 문제)

  • Lee, Heegwan
    • MISULJARYO - National Museum of Korea Art Journal
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    • v.100
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    • pp.82-110
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    • 2021
  • This study specifically examined the date of the black glazed bowls marked with "Gongyu (供御)" or "Jinzhan (進琖)" of Jian ware, one of the key research topics related to the bowls. The results of this study can be summarized as follows. Jian Kiln produced various shapes of black glazed bowls, but almost all of the inscriptions of "Gongyu (供御)" or "Jinzhan (進琖)" are found only in two certain type bowls: Type I, the Shukou type bowls (束口碗), or Type II, the Piekou type bowls (撇口碗). Of these, there are significantly more of the former in existence. For Type I bowls marked with "Gongyu (供御)" or "Jinzhan (進琖)", the mouth of the bowls is slightly evaginated outwards, and the inclination angle of the side slope is about 50°. The shape feature, Shukou (束口) is formed which is slightly indented around the bowl about 0.3~0.5cm below the mouth of bowl. And the height of the bowls is relatively low compared to other Type I black glazed bowls produced by Jian Kiln, so the height divided by the diameter is 0.5 or less. There is little difference in shape between the black glazed bowls marked with "Gongyu (供御) and those with "Jinzhan (進琖)". However, taking into consideration the excavation situation of both type bowls, the former is considered to be ahead of the latter in terms of production date. On the other hand, the black glazed bowls of Jian ware, which have the same shape features as the Type I bowls marked with "Gongyu (供御)" or "Jinzhan (進琖)" have not been found in the tombs dating from the end of the 12th to the beginning of the 13th century from which typical Jian kiln black glazed bowls of the same type were excavated. For the Hakata site (博多遺址) in Japan, the black glazed bowls with such a shape feature were excavated from early 12th century sites, rather than from the late 12th to early 13th century sites at which the typical black glazed bowls of Jian kiln were found. Considering that the black glazed bowls from Fujian province were imported into Hakata with almost no time gap, it is very unlikely that the production time of Type I black glazed bowls marked with "Gongyu (供御)" or "Jinzhan (進琖)" will deviate from the early 12th century. In conclusion, it is considered that the black glazed bowls marked with "Gongyu (供御)" or "Jinzhan (進琖)" of Jian ware were produced in the early 12th century.

Method of Reducing Separation Membrane Fouling Using Microbubbles (마이크로버블을 이용한 분리막 파울링 저감방법)

  • Kyung-Hwan Ku;Younghee Kim
    • Clean Technology
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    • v.29 no.1
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    • pp.31-38
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    • 2023
  • Due to water shortages caused by water pollution and climate change, total organic carbon (TOC) standards have been implemented for wastewater discharged from public sewage treatment facilities. Furthermore, there is a growing interest and body of research pertaining to the reuse of sewage treatment water as a secure alternative water resource. The membrane bio-reactor (MBR) method is commonly used for advanced wastewater treatment because it can remove organic and inorganic ions and it does not require or emit any chemicals. However, the MBR process uses a separation membrane (MF), which requires frequent film cleaning due to fouling caused by a high concentration of mixed liquor suspended solid (MLSS). In this study, process improvement and microbubble cleaning efficiency were evaluated to improve the differential pressure, water flow, and MF fouling, which are the biggest disadvantages of operating the MF. The existing MBR method was improved by installing a precipitation tank between the air tank and the MBR tank in which raw water was introduced. Microbubbles were injected into a separation membrane tank into which the supernatant water from the precipitation tank was introduced. The microbubble generator was operated with a 15 day on, 15 day off cycle for 5 months to collect discharged water samples (4L) and measure TOC. As the supernatant water from the precipitation tank flowed into the separation membrane tank, about 95% of the supernatant water MLSS was removed so the MF fouling from biological contamination was prevented. Due to the application of microbubbles to supernatant water from the precipitation tank, the differential pressure of the separation membrane tank decreased by 1.6 to 2.3 times and the water flow increased by 1.4 times. Applying microbubbles increased the TOC removal rate by more than 58%. This study showed that separately operating the air tank and the separation membrane tank can reduce fouling, and suggested that applying additional microbubbles could improve the differential pressure, water flow, and fouling to provide a more efficient advanced treatment method.

A Study on the Garden Culture and Ideology based on the Confucianism and Taoism of the Song Dynasty - Focused on Zhū Xī(朱熹) and Báiyùchán(白玉蟾) - (송대(宋代) 유가와 도교에 근거한 원림 문화와 사상 고찰 - 주희(朱熹)와 백옥섬(白玉蟾)을 중심으로 -)

  • Park So-Hyun
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.41 no.1
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    • pp.10-20
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    • 2023
  • Zhū Xī, the representative of Confucianism, and Báiyùchán, the representative of Taoism in the South Song Dynasty, showed different sense of appreciation and enjoyment on the same space that was Mountain Wǔyí in their ideologically cultural ways. Based on the temples Wŭyíjīngshè(武夷精舍) where Zhū Xī stayed and Zhĭzhĭān(止止庵) where Báiyùchán resided, this study revealed their lives in such temples to look into their appreciation on ideology and space. Then, based on the words 'YiBoEumYeong [移步吟詠]' shown on the poetry they chanted in relation with Wǔyíjiǔqū from its 1st valley to its 9th valley, this study examines their understanding of scenery and system of appreciation that appeared in dynamic ways to conclude: First, even same scenery shows different understanding of scenery and appreciation of space in accordance with the viewers' thinking ways of culture. Second, as the Confucianism and Taoism influenced in ideologically cultural ways to develop each other in the Song dynasty, they absorbed their merits each other to supplement shortcomings in their own. In this process, they made it clear that their own propositions were different between them in their essential meanings although they used common terms for such propositions. Third, as the Confucian master who compiled the Neo-Confucianism of the South Song dynasty, Zhū Xī regarded Wŭyíjīngshè and Wǔyíjiǔqū as a place of learning and a place of seeking the truth to go for 'being unified with nature' so that everyday life can be united with Tao of Li [理] everywhere beyond the limited appreciation of the scenery. That is, this thought works for 'recovery of nature of our own [復其性]', the learning goal of Confucianism, and is aimed to 'cultivate the essential nature of our own(性情涵養)' through such beautiful nature. Fourth, as the master of Keumdan family of the South Song Taoism, Báiyùchán regarded Zhĭzhĭān and Wǔyíjiǔqū as a Taoist temple that has a long history rooting from Taesangwon temple, a clean place of discipline to become a Taoist hermit through hard training. He, therefore, directly referred to Zhĭzhĭān and Wǔyíjiǔqū in relation with the Taoist legends remaining in Wǔyíjiǔqū such as hermits' dinners, female hermits, leaving the human world as a hermit and so on as ways for becoming a hermit so that he went for the level of perfectly going out of human world and becoming a hermit. He, therefore, defined Mountain Wǔyí as a world and universe of hermits where he himself too hovered between outside and inside of poetry literature as a hermit through the mood and attitude of keeping himself enjoying the scenery as a hermit.

A study on the field tests and development of quantitative two-dimensional numerical analysis method for evaluation of effects of umbrella arch method (UAM 효과 평가를 위한 현장실험 및 정량적 2차원 수치해석기법 개발에 관한 연구)

  • Kim, Dae-Young;Lee, Hong-Sung;Chun, Byung-Sik;Jung, Jong-Ju
    • Journal of Korean Tunnelling and Underground Space Association
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    • v.11 no.1
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    • pp.57-70
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    • 2009
  • Considerable advance has been made on research on effect of steel pipe Umbrella Arch Method (UAM) and mechanical reinforcement mechanism through numerical analyses and experiments. Due to long analysis time of three-dimensional analysis and its complexity, un-quantitative two-dimensional analysis is dominantly used in the design and application, where equivalent material properties of UAM reinforced area and ground are used, For this reason, development of reasonable, theoretical, quantitative and easy to use design and analysis method is required. In this study, both field UAM tests and laboratory tests were performed in the residual soil to highly weathered rock; field tests to observe the range of reinforcement, and laboratory tests to investigate the change of material properties between prior to and after UAM reinforcement. It has been observed that the increase in material property of neighboring ground is negligible, and that only stiffness of steel pipe and cement column formed inside the steel pipe and the gap between steel pipe and borehole contributes to ground reinforcement. Based on these results and concept of Convergence Confinement Method (CCM), two dimensional axisymmetric analyses have been performed to obtain the longitudinal displacement profile (LDP) corresponding to arching effect of tunnel face, UAM effect and effect of supports. In addition, modified load distribution method in two dimensional plane-strain analysis has been suggested, in which effect of UAM is transformed to internal pressure and modified load distribution ratios are suggested. Comparison between the modified method and conventional method shows that larger displacement occur in the conventional method than that in the modified method although it may be different depending on ground condition, depth and size of tunnel, types of steel pipe and initial stress state. Consequently, it can be concluded that the effect of UAM as a beam in a longitudinal direction is not considered properly in the conventional method.