• Title/Summary/Keyword: Natural

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Sesquiterpenes and Sterols from Aster glehni

  • Min, Yong-Deuk;Kwon, Hak-Cheol;Choi, Sang-Zin;Lee, Sung-Ok;Kim, Soo-Hak;Lee, Won-Bin;Yang, Min-Cheol;Chung, Ae-Kyung;Lee, Kyu-Ha;Nam, Kyu-Ha;Lee, Kang-Ro
    • Proceedings of the PSK Conference
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    • 2002.04a
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    • pp.200.2-200.2
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    • 2002
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New Hydroperoxides from Aster oharai

  • Park, Sang-Zin;Kwon, Hak-Cheol;Min, Yong-Deuk;Lee, Sung-Ock;Lee, Won-Bin;Yang, Min-Cheol;Chung, Ae-Kyung;Lee, Kang-Ro
    • Proceedings of the PSK Conference
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    • 2001.10a
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    • pp.258.2-259
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    • 2001
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Comparative Studies on Genetic Variabilities of Second Chromosomes in Sasang Natural and Experimental Populations of Drosophila melanogaster (자연과 실험집단내 Drosophila melanogaster 제 2 염색체의 유전적 변이성에 대한 비교 연구)

  • Son, Seong-Gon;Choe, Yeong-Hyeon;Lee, Won-Ho
    • Journal of Environmental Science International
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    • v.3 no.4
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    • pp.297-304
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    • 1994
  • The genetic variabilities of second chromosomes concealed Sasang natural and experimental populations of Drosophila melanogaster have been analyzed. The experimental population was composed of D. melanognter which had the lethal-free second chromosome collected from Sasang natural population in 1982. The results were as follow; The mean frequencies of deleterious genes were estimated % be 33.33% in Sasang natural population and 31.72% in experimental population. The allelism rates in lethal genes isolated from the natural and experimental populations were calculated to be about 0.95% and 12.28%, respectively. The allelism rates between lethal genes isolated from the natural population and those of the experimental population were calculated to be about 0.01%. The mean values of elimination by frequencies of deleterious genes and allelism rates were 0.0011 in the natural population and 0.0124 in the experimental population. The frequencies of phenotypic sterility of males in the natural and experimental populations were estimated to be 1.49% and 1.36%, respectively. The frequencies of genotypic sterility of females and males were estimated to be 0.90% and 1.80% in the natural population, and that of males was 2.38% in the experimental population.

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A Study on the Characteristics of Using Natural Light in Alvar Aalto's Library (알바 알토 도서관 건축의 자연광 사용 특성에 관한 연구)

  • Chung, Tae-Yong
    • Korean Institute of Interior Design Journal
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    • v.20 no.5
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    • pp.13-22
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    • 2011
  • The purpose of this study is to analyze Alva Aalto's libraries for understanding his efficient induction of natural light. To fulfill this purpose, Alvar Aalto's thought about library and natural light are examined through his working years and building types. The comparison of his libraries on usage of natural light shows different ways of natural light induction based on different locations and programs of libraries. Similarities and differences of Alvar Aalto's library architecture have strong relationship to the usage of natural light in libraries because Alvar Aalto himself regard reading as the core function of library and the efficient use of natural light is the main key of reading. In his natural light planning, regional characteristics including environmental factors and programmatic differences act as a basic standard for natural light plan. Especially, altitude of sun and its path, seasonal features affect the induction way of natural light. While conical skylights used at Viipuri library shows the characteristics of universality in Modernism architecture, later libraries presents not only various kinds of pan-shape plan but different ways of inducing natural light in according to appropriate function. From conical skylight to monitor with curved reflection wall make it possible shed diffused light to reading space and this affects to form Alvar Aalto's organic architecture. As a result, using natural light in Alvar Aalto's library architecture act as the core of forming library concepts and their development.

Characteristic Analysis of Natural Landscape: Based on the Assessments of Naturalness by Landscape Professionals and Laypersons (자연경관의 특질 분석 : 자연성에 대한 조경 전문가와 일반인의 평가를 중심으로)

  • 이영경
    • Journal of the Korean Institute of Landscape Architecture
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    • v.31 no.6
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    • pp.1-14
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    • 2004
  • As urbanization becomes widely spread, environmental benefits of natural landscapes have been highly appreciated. The social demands to conserve such landscapes are becoming stronger in modem society. In order to effectively manage natural landscapes, one should know what natural landscapes are. The characteristics of natural landscapes revealed by foreign research include wilderness, absence of human intrusion, and presence of diverse natural element (plants, trees, waters). The purpose of this paper is to investigate the characteristics of diverse natural landscapes with different levels of naturalness. The methods adopted here consist of three phases. First, 368 landscapes were photographed to include different levels of naturalness. Second, two professional landscape groups assessed the degree of naturalness of the collected landscapes, in which the characteristics of five degrees of naturalness were examined. Lastly, undergraduate students, as laypersons, assessed the 33 landscapes that were selected as representative of the five degrees of naturalness. The results show that there is no difference between professionals and laypersons on the assessment of naturalness of landscape. The characteristics of natural landscape that participants perceive include no human intrusion, preservation of original state, traditional quality such as Korean-style architecture, dominance of natural elements, and minimum facilities that harmonize with natural surroundings, Many characteristics are similar to the results of foreign research, However, the results reveal that Koreans do not perceive man-made nature as natural, while they perceive traditional elements as natural. Based on the results, some suggestions for landscape management are presented in the conclusion section.

Analysis of Natural Pigment Indicator Components of Natural Dyed Cotton Fabrics Using HPLC-DAD-MS (HPLC-DAD-MS를 이용한 천연염색 면직물의 천연색소 지표성분에 대한 분석)

  • Lee, Won Kyoung;Kim, Jong Hoon;Kim, Moon Jung;Park, Yoon Cheol;Lee, Bum Hoon
    • Textile Coloration and Finishing
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    • v.32 no.4
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    • pp.255-264
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    • 2020
  • With the development of synthetic dyes, excellent dyeing properties and massive production became possible. On the other hand, natural dyeing technology has gradually disappeared. However, the international environmental and human safety requirements of the apparel and textile industry are increasing, and there is a growing interest in safer and more environmentally friendly products. Accordingly, the public's interest in natural dyeing is increasing. To meet these demands, it is first necessary to clarify the stages of production and distribution of natural dyes. It is necessary to evaluate whether the product is a natural dye product and study the suitability of the natural dye product through qualitative and quantitative assessment of the indicator components of the natural dye. Typical of three natural dyes did qualitative and quantitative analysis by HPLC-DAD and HPLC-MS. Products dyed using natural dye three products were analyzed, and the presence or absence of detection of each indicator components was confirmed to confirm whether the product was dyed using natural dyes.

Fundarmental Studies on Regional Analysis of Potentiality for Conservation of Natural Park(II) -Analysis of Existing Natural Resources in Tokyo Province- (자연공원의 보호계획을 위한 광역적 토지자연의 분석에 관한 연구 (II) -잠재자연 및 현재자연과 보호를 위한 계획지침의 설정-)

  • 배병호
    • Journal of the Korean Institute of Landscape Architecture
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    • v.22 no.2
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    • pp.39-52
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    • 1994
  • Existing natural resources were analyzed in regional scale in order to suggest natural park guidelines as a previous step of conservation plan. Results of both existing natural resources and land potentiality in preceding paper were combined to suggest comprehensive and qualitative method for understanding of natural land. Regional characteristics of natural park were, then, analyzed by this method, and specific planning guidelines were discussed. The existing natural resources were analyzed by the degree of location quotient, which were found by comparison of the grade of vegetation naturalness and the bio-physical land unit in preceding paper. Then, allowance of existing natural resources was identified, and importance of protection was described based on this result. The bio-physical land unit on Tokyo Province was found to be composed by smaller land units, which had a variety of relationship with grade of vegetation naturalness: from the specific(1st) to many stages(5th). This meant a characteric of each land unit. By this combined approach, the characteristics and spatial distribution of natural land were discussed in the regional scale, and characteristic of nateral park were analyzed in terms of natural location. National park were located in the land unit where both land capability and importance of portection were the 6th. Quasi national park and 1 province natural park were located in the land unit where land capability was the 6th and importance of protection were the 5th. Seven province natural parks were located in the land unites were both criteria under the 5th were mixed. based on the results of this study, the followings were suggested for specific planning guidelines in the case of Takao quasi nation park: (a) conservative land use within the limit of carrying capacity of this area by the conservation of biotic and abiotic natural resources, (b) conservation of both natural and semi-natural vegetation, (c) utilization of this area as a urban forest.

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Code development on steady-state thermal-hydraulic for small modular natural circulation lead-based fast reactor

  • Zhao, Pengcheng;Liu, Zijing;Yu, Tao;Xie, Jinsen;Chen, Zhenping;Shen, Chong
    • Nuclear Engineering and Technology
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    • v.52 no.12
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    • pp.2789-2802
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    • 2020
  • Small Modular Reactors (SMRs) are attracting wide attention due to their outstanding performance, extensive studies have been carried out for lead-based fast reactors (LFRs) that cooled with Lead or Lead-bismuth (LBE), and small modular natural circulation LFR is one of the promising candidates for SMRs and LFRs development. One of the challenges for the design small modular natural circulation LFR is to master the natural circulation thermal-hydraulic performance in the reactor primary circuit, while the natural circulation characteristics is a coupled thermal-hydraulic problem of the core thermal power, the primary loop layout and the operating state of secondary cooling system etc. Thus, accurate predicting the natural circulation LFRs thermal-hydraulic features are highly required for conducting reactor operating condition evaluate and Thermal hydraulic design optimization. In this study, a thermal-hydraulic analysis code is developed for small modular natural circulation LFRs, which is based on several mathematical models for natural circulation originally. A small modular natural circulation LBE cooled fast reactor named URANUS developed by Korea is chosen to assess the code's capability. Comparisons are performed to demonstrate the accuracy of the code by the calculation results of MARS, and the key thermal-hydraulic parameters agree fairly well with the MARS ones. As a typical application case, steady-state analyses were conducted to have an assessment of thermal-hydraulic behavior under nominal condition, and several parameters affecting natural circulation were evaluated. What's more, two characteristics parameters that used to analyze natural circulation LFRs natural circulation capacity were established. The analyses show that the core thermal power, thermal center difference and flow resistance is the main factors affecting the reactor natural circulation. Improving the core thermal power, increasing the thermal center difference and decreasing the flow resistance can significantly increase the reactor mass flow rate. Characteristics parameters can be used to quickly evaluate the natural circulation capacity of natural circulation LFR under normal operating conditions.