• Title/Summary/Keyword: fiber analysis

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A Study on the Ignition Behaviors of Textiles according to Permeation Amount of Oils and Aeration (유지류의 침윤량과 공기주입에 따른 면화류의 발화거동에 관한 연구)

  • 오치훈;이창우;김정환;현성호
    • Fire Science and Engineering
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    • v.14 no.1
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    • pp.8-12
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    • 2000
  • We had investigated thermal and ignition behaviors of textiles. Decomposition of textiles with temperature was investigated using a DSC and the weight loss according to temperature using a TGA in order to find the thermal hazard of textiles, and the ignition behaviors of textiles according to species and permeation amount of oil. In addition, ignition behaviors of those permeated into oils indicating different iodine value and of those with arid without air in reaction vessel of measuring equipment were studied with constant temperature method among ignition temperature measuring methods. As results, the range of decomposition temperature of synthetic fiber was slightly broad compared with that of natural fiber, pure cotton. Besides, the initiation temperature of heat generation of both samples riced in the case of no air injection in the reaction vessel. On the other hand, in the case of air injection that was lowered according to the increase in permeative amount of oils and fats and decreased quickly as sample was permeated into drying oil.

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Measurement and Analysis of Image Brightness in Fiber-optic Imageguide for Ultrathin Endoscope (미세내시경용 광섬유 영상가이드의 영상광도 측정 및 분석)

  • 이봉수
    • Journal of Biomedical Engineering Research
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    • v.23 no.4
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    • pp.263-268
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    • 2002
  • The image quality of imageguide depends on the structure, material, length of microfibers and the phenomena such as cross-talk and leaky ray between adjacent fibers. These Parameters should be considered as important factors in the image transmission qualify of fibers. However it is considered to be very difficult to assess all the parameters in a consistent way Therefore. two image characteristics, image resolution and image brightness are measured and analyzed to determine the image quality of imageguide. But the exact methods to measure two image characteristics of imageguide are not reported. In this study, the image brightness of imageguide for ultrathin endoscope is determined by measuring of the numerical aperture. the packing fraction and the attenuated power ratio of imageguide. Especially it is possible to obtain more exact results from measuring the numerical aperture of whole image guide than those from theoretical calculation of the single microfiber in an image guide. The image brightness of the image guide which has $3.1\mu m$ microfibers is about 37% less than that with $4.1\mu m$ microfibers.

The Shear Resistance of Rc Deep Beam with Web Opening Repaired and Reinforced by Fiber Sheets After Shear Failure (깊이가 큰 철근콘크리트 유공보의 보수·보강 전후의 내력에 관한 연구)

  • Yang, Chang-Jin
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.8 no.3
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    • pp.149-158
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    • 2004
  • In this study, deep beam specimens are designed to have the effective shear span to depth ratio 1.0 and web opening within effective shear region. The purpose of this study is to investigate experimentally the shear strengthening effect between before failure and after failure upon using fiber sheets for RC deep beam with opening in web. The results can be summarized as follows; 1)When deep beams with web opening were failed in shear, their initial diagonal crack load and crack width were not influenced by their types of the arranged steel bars. 2)Deep beam with the horizontal reinforced bar was effective in the ultimate load of deep beam with web opening in shear failure 3)There were the approximate values between the experimental values and the analysis of finite element method. 4)The ultimate failure strengths of the repaired and strengthened specimens were increased about 34.4%~83.8% in comparison with specimens not to be strengthened.

Synthesis of Sulfonated Hollow PP-g-Styrene Fibrous Ion-exchange Membrane and Separation of BSA Protein (술폰화 PP-g-Styrene 중공사 이온교환막의 합성과 BSA 단백질 분리에 관한 연구)

  • 황택성;이진혁
    • Polymer(Korea)
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    • v.26 no.4
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    • pp.415-421
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    • 2002
  • A sulfonated PP-g-styrene ion-exchange hollow fiber membrane was prepared by pre-irradiation method with E-beam followed by sulfonation reaction. Degree of grafting increased with the increase of styrene monomer concentration and showed the maximum value of 128% at 80% of styrene monomer composition. Sulfonation yield increased with the degree of grafting. At 100% degree of grafting, sulfonation yield showed the maximum value of 13.4%. Ion exchange capacity of sulfonated HPP-g-styrene of 3.42 meq/g was attained, resulting in the remarkable increase of adsorption ability BET analysis proved that the surface area of sulfonated HPP-g-styrene was 62.54 $m^2/g$ and the mean pore size was 25 $\AA$. From the BSA adsorption experiments, the adsorption amount of BSA was increased with sulfonation. At 13.4% sulfonation yield the adsorption amount of BSA was maximum as 3.8 mg/g. Sulfonated HPP-g-styrene was synthesized successfully and suitable for the adsorption and separation of BSA.

A comparative analysis of business management characteristics among textiles and fashion companies - Focused on revenue, income, and expense items in income statements - (섬유패션업체들의 경영 특성 비교 - 손익계산서의 수익, 이익, 비용항목을 중심으로 -)

  • Ji, Hye Kyung
    • The Research Journal of the Costume Culture
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    • v.25 no.3
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    • pp.359-374
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    • 2017
  • The objective of this study was to compare business management indicators among textiles and fashion companies. Business management indicators of 356 textiles and fashion companies for the year 2015 were analyzed, using income statements showing their management results. The results were as follows. First, there were statistically significant differences between the operating income ratios of textiles and fashion companies for the term, but there were none when it came to net income ratio. Second, the differences between cost of goods sold, cost of finished goods sold, and cost of merchandise sold to sales ratios among textiles and fashion companies were all statistically significant. The cost of goods sold, cost of finished goods sold, and cost of merchandise sold to sales ratios were higher for fiber and thread companies, fabric companies, and dyeing and finishing companies than for clothing and fashion accessories companies. Third, there were statistically significant differences between the ratio of salaries and the ratio of advertising expenses among textiles and fashion companies. The salaries ratios and advertising expenses ratios for clothing companies were higher than those of fiber and yarn companies, fabric companies, and dyeing and finishing companies. This study is meaningful as it has identified the business characteristics of textiles and fashion companies using the management indicators of those companies, which have not been sufficiently explored by previous studies. It has also helped to improve understanding of the industrial structure of the upstream and midstream sectors of the textiles and fashion industries.

Micromechanics-based Analysis on Tensile Behavior of the Sprayed FRP Composites with Chopped Glass Fibers (유리단섬유로 보강된 분사식 섬유보강 복합재료의 인장거동에 관한 미세역학 기반 해석)

  • Yang, Beom-Joo;Ha, Seong-Kook;Lee, Haeng-Ki
    • Journal of the Computational Structural Engineering Institute of Korea
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    • v.25 no.3
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    • pp.211-217
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    • 2012
  • In this paper, experimental tests and theoretical studies were carried out to evaluate the tensile behavior of the sprayed FRP composite with chopped glass fiber. For this, a series of tensile strength tests with various strain rates were conducted on the specimens of the matrix and sprayed FRP composite. Sprayed FRP composite contained chopped glass fibers with fiber length of 15mm and a specific volume fraction of fibers of 25 %. An inverse simulation was conducted to simulate the strain rate sensitivity based on the present experimental data of the epoxy resin. The simulated viscosity value is adapted to the micromechanics-based viscoelastic damage model(Yang et al., 2012), and the overall tensile behavior of sprayed FRP composites is predicted. It was seen from the comparative study between present experimental data and predication results that the proposed methodology can be used to predict the viscoelastic behavior of the sprayed FRP composite.

Analysis of RTM Process to Manufacture Composite Bogie Frame Considering Fiber Orientation (섬유방향성을 고려한 복합소재 대차 프레임의 RTM 성형 특성 해석)

  • Kim, Moo Sun;Kim, Jung-Seok;Kim, Seung Mo
    • Journal of the Korean Society for Railway
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    • v.18 no.4
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    • pp.301-308
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    • 2015
  • To reduce the weight of a railroad vehicle, a bogie frame skin is considered for manufacture using an RTM process and composite material. Compared to other processes, RTM has merits in that it demands only simple manufacturing facilities and can produce a large and complex structure in a short cycle time. On the other hand, it is important to determine the proper number and locations of gates and vents to prevent void formation inside a structure. In this study, we numerically predicted the flow pattern in a bogie frame skin during the RTM process by distinguishing the permeability of a fiber mat as isotropic or anisotropic. Using the results, we analyzed the RTM process conditions of the bogie frame to predict skin void formation, mold filling time, and optimum location of vents depending on the permeability conditions.

The Protective Effects of Pueraria Radix against Chronic Alcohol-induced Muscle Atrophy in Rats (알콜로 유도된 흰쥐의 근위축에서 갈근(葛根)의 보호 작용과 그 기전에 대한 고찰)

  • Kim, Bum Hoi
    • Journal of Korean Medicine Rehabilitation
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    • v.27 no.2
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    • pp.1-8
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    • 2017
  • Objectives Ethanol is a potent inhibitor of muscle protein synthesis. Muscle mass is regulated by the balance between rates of protein synthesis and protein breakdown. Both acute and chronic alcohol consumption inhibits synthesis to a greater extent than degradation. Protein synthesis is more intensely decreased in type II fibers than in type I fibers. Apoptosis has been shown to occur frequently in a variety of tissues in response to chronic alcohol feeding. Increased muscle fiber apoptosis has been shown in alcoholics with myopathy. Pueraria radix has been used for many disorders such as fevers, gastrointestinal disorders, muscle aches, allergies, respiratory problems, skin problems, high blood pressure, migraine headaches, lowering cholesterol and treating chronic alcoholism. We therefore tested the hypothesis that oral treatment with Pueraria radix could reduce the ethanol-induced muscle atrophy. Methods Young male Sprague-Dawley rats were orally given 25% ethanol (5 ml/kg, body weight) daily with Ethanol for 4 weeks. Normal group was similarly administrated with saline. The Rats of Pueraria radix treated group (EtOH+PR) were orally administrated Pueraria radix water extract, and rats of EtOH group were given with the vehicle only. After 4 week, the morphology of gastrocnemius and plantaris muscles were assessed by hematoxylin and eosin staining. The immunoreactivities of pre-apoptotic BAX and anti-apoptotic Bcl-2 proteins were also measured. Results The muscles from rats of EtOH group represented a significant reduction in average cross section area compared to Normal group. EtOH+PR group had increased fiber compared to the EtOH group. Moreover, to investigate the ethanol-induced muscular apoptosis, the immunohistochemical analysis of Bax and Bcl-2 was carried out. The treatment with Pueraria radix (EtOH+PR) significantly decreased BAX expression and increased Bcl-2 expression 4 weeks after ethanol administration when compared with Normal group. Conclusions These results suggest that Pueraria radix water extract has protective effects on chronic alcohol induced myopathy.

A Study on P-M Interaction Diagram of Fire-Damaged High Strength Concrete Column (화재 피해를 입은 고강도 RC 기둥의 P-M 상관곡선에 관한 연구)

  • Kim, Hyun-Jung;Choi, Eun-Gyu;Shin, Yeong-Soo
    • Proceedings of the Korea Concrete Institute Conference
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    • 2008.04a
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    • pp.257-260
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    • 2008
  • This study will make P-M interaction diagram of residual capacity at fire-damaged High strength concrete column with polypropylene fiber. Evaluating capacity of column decreasing spalling with P-M interaction diagram is important. because high strength concrete column with polypropylene fiber isn't section area loss. P-M interaction diagram that is made to analyze according to a various parameters is useful index for design and evaluating capacity of columns. In this study, spalling, temperature distribution of interior column, residual strength and movement of column in eccentric loading are studied with expose time of high temperature. For study fire test that is similar real act, and after cooling in normal condition residual strength of specimen is estimated. And this study use DIANA(Displacement Analyzer) for analyzing nonlinear analysis. with experiment temperature and strength data.

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The Analysis of Energy Character and Synthesis of Lithium-Carbon Intercalation Compounds (리튬-탄소층간화합물의 합성과 에너지 특성의 분석)

  • 오원춘;백대진;고영신
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.3 no.2
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    • pp.167-175
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    • 1993
  • Lithium-Carbon Intercalation Compounds(Li-CICs) have been synthesized from various carbon ma-terials by use of the modified stainless steel two-bulbs methods. These compounds had various colours by structural character of starting materials. The synthesized Li-CICs were identified to stage formation process by X-ray diffraction data. At these results, well-oriented natural graphite and graphite fiber are formed lower stages(Stage 1, Stage 2), but poor-oriented carbon fiber and petroleum cokes are also formed higher stages(Stage 3, Stage 4, Stage 5). And when we compared with measured d value and calculated d value, these values agreed with each other. But poor-oriented carbon materials are some difference from them. The stage stability and energy stage of Li-CICs were obtained by UV/VIS Spectrophotometric data. X-ray diffraction and UV/VIS Spectrophotometric data suggested that well-oriented carbon materials has distingushible curve between energy and reflectance. In these results, we know that many charge carriers between carbon layers are related to concentration of intercalants. And then, this paper also provides information on high efficiency energy storing materials at intercalation process of Li-CICs.

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