• 제목/요약/키워드: Natural components

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환경의 구성요소와 그 체계 (The Components of Environment and Their System)

  • 정대연
    • 환경영향평가
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    • 제10권3호
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    • pp.175-194
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    • 2001
  • The environment is composed of at least two components, the natural and the human-made one. Nonetheless, the environment is being used to connote the natural environment. Moreover, even though the components of environment exist in a mutual relationship as a mechanism, it is rare to study the components of environment and their system as a mechanism. With such an implication, this paper aims to identify the components of environment and their system. The components of environment can be categorized by two criteria. One is the subject of creating environment, and the other is the visuality of environment. The former categorizes the environment into the natural and the human-made one, and the latter into physical and nonphysical one. Integrating the two criteria into a framework, the environment can be categorized into the natural, the human-made physical, and the human-made nonphysical environment. The three categories of environment exist interrelatedly in a mechanism being characterized as a mutual impact. The mechanism may be called the environmental system. The environmental system can be analyzed in terms of two dimensions. One is a human-inclusive system. The other is a human-centered system. The former is a framework that includes humans as a component of environment. The latter is a framework that humans are the subject of the environment, and the others surrounding human life are the object of the environment. The former is defined as a circular system of material and energy, while the latter is defined as a mutual subjective-objective system.

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

  • 이원경;김종훈;김문정;박윤철;이범훈
    • 한국염색가공학회지
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    • 제32권4호
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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.

Quality Assessment of Curcuma longa L. by Gas Chromatography-Mass Spectrometry Fingerprint, Principle Components Analysis and Hierarchical Clustering Analysis

  • Li, Ming;Zhou, Xin;Zhao, Yang;Wang, Dao-Ping;Hu, Xiao-Na
    • Bulletin of the Korean Chemical Society
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    • 제30권10호
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    • pp.2287-2293
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    • 2009
  • Gas Chromatography-Mass Spectrometry (GC-MS) fingerprint analysis, Principle Components Analysis (PCA), and Hierarchical Cluster Analysis (HCA) were introduced for quality assessment of Curcuma longa L. (C. longa). The GC-MS fingerprint method was developed and validated by analyzing 33 batches of samples of C. longa from different geographic locations. 18 chromatographic peaks were selected as characteristic peaks and their relative peak areas (RPA) were calculated for quantitative expression. Two principal components (PCs) were extracted by PCA. C. longa collected from Guizhou and Fujian were separated from other samples by PC1, capturing 71.83% of variance. While, PC2 contributed for their further separation, capturing 11.13% of variance. HCA confirmed the result of PCA analysis. Therefore, GC-MS fingerprint study with chemometric techniques provides a very flexible and reliable method for quality assessment of C. longa.

철근콘크리트 구조물 내의 철근을 활용한 피뢰설비 인하도선의 설치방법에 관한 연구 (A Study on the Installation Method of Down Conductors of the Lightning Protection System, using Rebar in Reinforced Concrete Structures)

  • 이영철;이주철
    • 조명전기설비학회논문지
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    • 제27권7호
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    • pp.101-107
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    • 2013
  • IEC Standards on lightning protection system specify the use of natural components as down conductors. This paper provides an analysis of problems revealed from our field investigation and survey conducted for the relevant experts in the construction site where natural components are used as down conductors. It also considers a suitable condition for installing natural components as down conductors in accordance with the latest version of the standard. As a result, when rebars of reinforced concrete are used as down conductors, vertical bars consisting of rebars of which thickness is not less than D13($127mm^2$) should be connected by welding, clamps or bound joints, using appropriate connection components conforming to IEC Standards. The lashed joints, however, shall not be applied for down conductors.

Vibration of mitred and smooth pipe bends and their components

  • Redekop, D.;Chang, D.
    • Structural Engineering and Mechanics
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    • 제33권6호
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    • pp.747-763
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    • 2009
  • In this work, the linear vibration characteristics of $90^{\circ}$ pipe bends and their cylindrical and toroidal shell components are studied. The finite element method, based on shear-deformation shell elements, is used to carry out a vibration analysis of metallic multiple $90^{\circ}$ mitred pipe bends. Single, double, and triple mitred bends are considered, as well as a smooth bend. Sample natural frequencies and mode shapes are given. To validate the procedure, comparison of the natural frequencies is made with existing results for cylindrical and toroidal shells. The influence of the multiplicity of the bend, the boundary conditions, and the various geometric parameters on the natural frequency is described. The differential quadrature method, based on classical shell theory, is used to study the vibration of components of these bends. Regression formulas are derived for cylindrical shells (straight pipes) with one or two oblique edges, and for sectorial toroidal shells (curved pipes, pipe elbows). Two types of support are considered for each case. The results given provide information about the vibration characteristics of pipe bends over a wide range of the geometric parameters.

천연가스 음속과 열전도도 상관식을 이용한 발열량 측정기술 (Measuring calorific values of natural gases using sound velocity and thermal conductivity)

  • 이주행;최병철;최인철
    • 한국연소학회:학술대회논문집
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    • 한국연소학회 2015년도 제51회 KOSCO SYMPOSIUM 초록집
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    • pp.57-59
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    • 2015
  • A method to measure heating value of natural gas using sound velocity and thermal conductivity is proposed to solve the low heating value issues of imported natural gas in South Korea. Natural gas generally consists of methane, butane, ethane, and inert gases. Heating value changes as the gas material properties, such as density, wobbe index, etc., varies. It is highly important to measure heating values of natural gases accurately because measuring the heating value depends on the given natural gases' components. Therefore, sound velocity and thermal conductivity is measured to estimate indirectly heating value of Natural gas with their changed components.

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Exploring Science Communication in Panels of Exhibitions and Proposing its Development Direction in Exhibition Education: Two cases of Natural History Museum

  • Park, Young-Shin;Choi, Eunji;Ryu, Hyo-Suk
    • 과학교육연구지
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    • 제38권1호
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    • pp.205-229
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    • 2014
  • The purposes of this study were to explore what components of science communication and its level are contained in text panels of exhibitions in natural history museums and to propose its development direction of exhibition education in Korea. First, to find out the component and level of science communication contained in exhibition panels, the researcher team developed the analyzing tool which was called SEPAT (Science Exhibition Panel Analyzing Tool), then employed them to profile the component and level of science communication. Second, the researchers introduced the exemplary designed media of exhibitions to demonstrate how much science communication could be enhanced. The results were made as follows. First, the components of science communication was considerably weighted toward to 'concept' one. There were also a few 'awareness' and 'engagement', both of which were under 5% in each zone of exhibition and there was not 'NOSI' or 'opinion' embedded in the analyzed exhibitions. Second, the various type of designing exhibitions were found to promote or enhance the restrictedly represented components of science communication. It is suggestable for exhibitions to be designed through various type of 'media' to enhance science communication. Visitors are required to experience rich science communication to meet their educational needs, and exhibition developers in natural history museums and other museums are recommended to be professional in containing all components of science communication through various type of designing exhibitions.

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Studies on the antioxidant components of Korean ginseng 3

  • Han, Byung-Hoon;Park, Myung-Hwan;Nam, Han-Yong
    • Archives of Pharmacal Research
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    • 제4권1호
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    • pp.53-58
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    • 1981
  • The effective components of Korean ginseng showing the lipid-peroxide depressing activity were isolated. From the ether-soluble acidic fraction of fresh ginseng three phenolic acids were obtained. Salicylic acid and vanilic acid exhibited the potent antioxidant activity, where p-hydroxycinnamic acid did not.

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인삼(人蔘) polyacetylene 조성(組成)의 경시변화(經時變化) (Time Course Change in Composition of Ginseng Polyacetylenes)

  • 한병훈;송병준;노환성
    • 생약학회지
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    • 제7권3호
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    • pp.191-193
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    • 1976
  • It has been known that ginseng extract contains several polyacetylene components. But we found only two polyacetylene components in the freshly prepared ginseng extract. Long-term preservation of ginseng or ginseng extract produced many artifact polyacetylenes. The ratio of artifact/genuine polyacetylene was determined by TLC-densitometry on long-term preserved ginseng samples. The results indicated that the ratio was increased proportionally with the span of preservation.

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