• Title/Summary/Keyword: Content Structure

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Effects of Dimethipin on the Senescence of Excised Barley First Leaves (Dimethipin이 절단한 보리 제 1엽의 노쇠에 미치는 영향)

  • 전방욱
    • Journal of Plant Biology
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    • v.33 no.1
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    • pp.25-30
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    • 1990
  • Effects of dimethipin on the senescence of excised barley first leaves were investigated. Dimethipin markedly inhibited chlorophyll and protein loss and reduced peroxidase activity relevant to senescence phenomena in th excised leaves. Dimethipin decreased hydrogen peroxide content, later malondialdehyde content, and increased the activities of superoxide dismutase and catalase. The antisenescence effects of dimethipin may result from the stabilization of membrane structure through inhibiting the peroxidation of unsaturated lipid and the accumulation of free radicals during senescence.

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Consideration on the Risk of Corrosion Assessment in Reinforced Concrete Structure by Corrosion Potential Criterion (부식전위 기준에 의한 철근콘크리트 구조물의 부식진단의 위험성에 관한 고찰)

  • Jeong, Jin-A
    • Corrosion Science and Technology
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    • v.14 no.3
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    • pp.147-152
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    • 2015
  • Corrosion of steel reinforcement is a major factor in the deterioration of harbour and bridge structure. Steel corrosion in concrete must be checked for assessing the condition of a reinforced concrete structure. There are several ways how to measure the corrosion condition of reinforced concrete, but the corrosion potential measurement is a very simple, rapid, cost-effective and non-destructive technique to evaluate the severity of corrosion in reinforced concrete structure, therefore commonly used by engineers. However some particular situations may not relate to the reinforcement corrosion probability and a simple comparison of the corrosion potential data with the ASTM C876 Standard on steel reinforcement corrosion probability could be meaningless and not give reliable informations because of environment factors as oxygen concentration, chloride content, concrete resistance. Therefore this paper explains the risk of corrosion assessment in reinforced concrete structure and how many factors can affect the reliability of the corrosion potential data.

Effect of γ-Irradiation on the Molecular Properties of Bovine Serum Albumin and β-Lcatoglobulin

  • Cho, Yong-Sik;Song, Kyung-Bin
    • BMB Reports
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    • v.33 no.2
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    • pp.133-137
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    • 2000
  • To elucidate the effect of oxygen radicals on the molecular properties of proteins, the secondary and tertiary structure and molecular weight size of BSA and ${\beta}$-lactoglobulin were examined after irradiation of proteins at various doses. Gamma-irradiation of protein solutions caused the disruption of the ordered structure of protein molecules as well as degradation, cross-linking, and aggregation of the polypeptide chains. As a model system, BSA and ${\beta}$-lactoglobulin were used as a typical ${\alpha}$-helical and a ${\beta}$-sheet structure protein, respectively. A circular dichroism study showed that the increase of radiation decreased the ordered structure of proteins with a concurrent increase of aperiodic structure content. Fluorescence spectroscopy indicated that irradiation quenched the emission intensity excited at 280 nm. SDS-PAGE and a gel permeation chromatography study indicated that radiation caused initial fragmentation of proteins resulting in a subsequent aggregation due to cross-linking of protein molecules.

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Matrix Development in Cast Iron by Addition of Mischmetal Hydrides (주철(鑄鐵)의 기지조직(基地組織)에 미치는 Mischmetal Hydride의 첨가효과(添加效果))

  • Choi, Dap-Chun;Jin, Young-Chul
    • Journal of Korea Foundry Society
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    • v.8 no.4
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    • pp.422-428
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    • 1988
  • In this study we have investigated the effects of Mm, MmH and $MmH_2$ on the matrix development in cast iron, The conclusive summary is as follows: The spheroidal graphite was observed when 0.5wt.% or more of mischmetal was added and the matrix was of ledeburite structure, but bull's eye structure was not observed. On the other hand, the bull's eye structure was observed when 0.25wt.% of MmH, or 0.25wt.% to 0.5wt.% of $MmH_2$ was added. Above limit of the additives, the matrix changed into ledeburite structure. As the hydrogen content of mischmetal compound increased from MmH, the range of additives to obtain bull's eye structure expanded. This reveals the significant effect of mischmetal hydride on matrix development in cast iron and the possibility of practical use of the additives.

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Design and Implementation of a XML Document Retrieval System Using the BRS/Search System (BRS/Search 시스템을 이용한 XML 문서 검색시스템 설계 및 구현)

  • 손충범;이병엽;유재수
    • Journal of Internet Computing and Services
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    • v.2 no.2
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    • pp.51-63
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    • 2001
  • In this paper, we design and implement a XML document retrieval system to support structure-based retrieval using the BRS/Search system that is a commercial search engine, The implemented system in this paper represents the logical structure of XML documents as the directory structure of the Unix file system. In addition, we define the database schema of BRS/Search system to store documents, We also implement a ETID extractor, a structure information extractor, a storage manager and a query processor additionally to support content retrieval, structure retrieval, mixed retrieval and attribute retrieval in the BRS/Search system.

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Damage Assessment and A seismic Capacity Evaluation of Existing Structures (기설구조물의 손상도추정 및 내진능력평가 방법에 관한 연구)

  • 윤정방;송종걸;김유진
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 1998.04a
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    • pp.414-421
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    • 1998
  • The content of this paper consists of two related subjects. One is the assessment of damages in the existing structure and the other is the evaluation of seismic capacity of the structure with damage. A method is presented for damage assessment of existing structures using the modal data measured at limited points by the inverse medal perturbation technique. For efficient damage assessment, the number of the unknown probable damaged members is reduced for each damage identification by grouping the members in the large structure. The aseismic capacity is evaluated for the structure using the results of damage assessment. An example analysis is carried out for a building structure subjected to different earthquake excitations.

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Changes in Tissue Structure and Pectins of Chinese Cabbage during Salting and Heating (염절임 및 가열에 의한 배추조직의 구조와 펙틴의 변화)

  • Yoo, Myung-Shik;Kim, Ju-Bong;Pyun, Yu-Ryang
    • Korean Journal of Food Science and Technology
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    • v.23 no.4
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    • pp.420-427
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    • 1991
  • The structure of fresh, salted and heated petiole tissue from Chinese cabbage was examined with optical microscope, and the pectin of the tissues was fractionated by successive extraction. The pectin in Chinese cabbage consisted mainly of high methoxyl pectin(pA) and low methoxyl pectin(pB). The pA content was converted to pB markedly by salting and heating at $60{\sim}70^{\circ}C$ for 30 min while heating the cabbage above 80 decreased pB content. The firmness of heated tissue was highly correlated with pB content(r=0.996). Cytorrhysis test showed that pore size of the tissue became smaller by salting and heating at temperature below $80^{\circ}C$.

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A Study on the Chemical Composition and Structure of Sludge, Compost and Charcoal (폐수처리 슬럿지와 퇴비 및 목탄의 화학적 특성과 구조에 관한 연구)

  • 임기표;위승곤
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.35 no.1
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    • pp.27-32
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    • 2003
  • To understand the chemical structure of sewer sludge in comparison with commercial compost and charcoal used as a soil improver, it was carried out to analyse their ash contents and metal ions, and to elucidate the chemical structure of their residuals after a sequential treatment of alcohol-benzene(1:2) extraction in Soxhlet, 3% HCl reflux and 79% H₂SO₄ hydrolysis, using CHNS analyzer and solid C-13 NMR spectrometer. The results obtained were as follows: 1. Ash content of sludge was about 46% that is higher than those of compost (17%) and charcoal (4%). 2. The residual of sludge after a sequential treatment of HCl and H₂SO₄ hydrolyses had high ash content about 23%, too. 3. The sludge seems to be suitable to the soil improver because the content of heavy metal ions in sludge was near the compost and below the organic fertilizer standard. 4. Elemental composition of sludge residual after HCl-H₂SO₄ hydrolyes was C/sub 56/H/sub 91/O/sub 12/N₂S = (C/sub 6/H/sub 10/O/sub 5/)/sub 7/(C/sub 6/H₄)/sub 7/C₂H/sub 43/O₂N₂S, similar to C/sub 103/H/sub 122/O/sub 33/N/sub 6/S = (C/sub 6/H/sub 10/O/sub 5/)/sub 6/(C/sub 6/H₄)/sub 10/C/sub 7/H/sub 22/O₃N/sub 6/S of compost. 5. The sludge residual had proved to have both considerable aliphatic and aromatic groups, but the compost residual to have mainly aliphatic groups and the charcoal to have mainly aromatic groups, through the peak analysis of solid C-13 NMR charts. 6. So, the sewer sludge is proved to have a considerable amount of aromaticity like in woody biomass containing lignin.

The Current Status of 3D Printing Use in Fashion Industry and Utilization Strategies for Fashion Design Departments (패션 산업 내 3D 프린팅 사용 현황 및 패션디자인과 내의 활용방안)

  • Jeong, Hwa-Yeon
    • Journal of the Korea Fashion and Costume Design Association
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    • v.18 no.3
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    • pp.245-260
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    • 2016
  • This study explored cases of 3D printing utilization in domestic and overseas fashion industries, and presented utilization strategies for fashion design departments in universities in future by grasping characteristics of newly appearing distribution types through 3D printing. Cases of producing costumes using 3D printing in fashion industry comprised a bikini using the material of Nylon12 that continuum fashion demonstrated, innovative 3D costumes by Iris Van Herpen, Tweed Suit using the material that Chanel manufactured with 3D printing technology, but they were limited to experimental fashion works due to limitations of 3D printer material and printing size. On the other hand, in fashion accessories, with jewelry and shoes at the head of the list, MCM and Kipling also demonstrated bags using this technology, and Elvis Pompilio and Gabriela Ligenza demonstrated 3D printing hat products as well. Except the above, as in glasses and neckties utilizing 3D printing, owing to reduced limitations of time, size and material, 3D printing was found to be utilized in fashion accessories other than costumes. Recently there has been a new consumption and distribution structure coming up focusing on 3D printing technology. That is, in overseas countries, content platforms sharing products modeled by oneself has rapidly appeared, and in our country as well, funnypoly, a 3D content platform appeared in 2015. The appearance of these new types of distribution structures means that the common people can produce design contents, and we believe that it may bring about a change in the traditional way of distribution structure. To walk in step with this change, it is believed that it is necessary for fashion design departments to raise college faculty members who can educate 3D printing, develop curriculum to educate 3D printing, and develop experiential programs connected with middle and high schools.

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Structure and Thermal Properties of SnO2-(1-x)P2O5-xB2O3 Glasses (SnO2-(1-x)P2O5-xB2O3 유리의 열적, 구조적 특성)

  • An, Yong-Tae;Choi, Byung-Hyun;Ji, Mi-Jung;Chang, Woo-Suk;Bae, Hyun;Hwang, Hae-Jin
    • Journal of the Korean Ceramic Society
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    • v.47 no.2
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    • pp.117-121
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    • 2010
  • $SnO_2-(1-x)P_2O_5-xB_2O_3$ glass system were prepared by melt-quenching technique in the compositional series containing 50, 55 and 60 mol% of $SnO_2$. Local structure of the glasses was investigated by Raman and FT-IR measurements. A large glass-forming region was found at the phosphate side of the ternary system with homogeneous glasses containing up to 5~25 mol% of $B_2O_3$. According as content of $B_2O_3$ increases, theraml expansion coefficient of glass decreased but transition temperature and softening temperature increased. Because these phenomenon changed local structure of glass. According as content of $B_2O_3$ increases, quantity of bridging oxygen increased. Also, according as content of $SnO_2$ increases, confirmed that quantity of non-bridging oxygen increases.