• 한국식품위생안전성학회지
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• 제7권4호
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• pp.153-163
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• 1992

Dietary fiber imparts both mutritional and functional properties to foods. This review deals with (1) the classification of dietary fiber, (2) the plant cell wall models, (3) the relations between structure and physicochemical and functional properties of dietary fiber and (4) the applications of dietary fiber in foods. Dietary fiber can be classified in terms of source, plant function, solubility, charge and topology. Plant cell wall models are presented to provide information on the interconnections of dietary fiber components which determines the content of soluble and insoluble dietary fiber content. In reality, physicochemical and functional properties of dietary fiber originate factors such as chemical constituents , charge, branching degree, conformation and etc. Dietary fibers possess a variety of functional properties in food systems, which thus make them useful in food application. In particular, rheology and gelation of water-soluble gums or hydrocolloids are discussed for their effects on food quality. A guideline s also listed for the gum selection to meet the best product requirements.

• 한국식품과학회지
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• 제21권2호
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• pp.269-275
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• 1989

현율무, 율무쌀, 율무겨 그리고 현염주를 시료로 하여 일반성분, 총 식이섬유 함량, acid detergent fiber 함량, lignin 함량, 수분 결합력, 아미노산 조성 및 중성지질 조성 등을 살펴보았다. 그 결과, 율무쌀의 총 식이섬유량은 2.70% 였고, 현율무는 3.86% 였으며 현염주는 4.33% 그리고 율무겨는 13.12%였다. Acid detergent fiber 양은 율무쌀이 1.81%로 가장 낮았고 현율무, 현염주는 각각 3.45%, 3.26%로 비슷한 값이었다. 율무겨에서 추출한 총 식이섬유와 acid detergent fiber 의 수분 결합력을 측정하여 비교한 바 총 식이섬유의 수분 결합력은 $2.63{\pm}0.02g\;H_2O/g\;TDF$로 매우 낮았고, acid detergent fiber의 수분 결합력은 $5.89{\pm}0.152g\;H_2O/g\;ADF$였다. 율무쌀, 현율무, 현염주 그리고 율무겨의 아미노산 조성은 glutamic acid 함량이 가장 높았고 다음이 leucine 이었으며, 율무쌀의 경우 leucine 의 chemical score는 189로 매우 높았으며 반면에 lysine의 chemical score는 22-32 사이로 매우 낮아 율무, 염주의 제한 아미노산이 되었다. 지질성분은 중성지질이 80.89%-96.55% 범위로 대부분을 차지했고, 당지질이 2.35%-7.48% 사이로 현염주의 당지질 함량이 가장 낮았다. 인지질은 함량이 매우 낮아서 1.10%-2.12% 범위였다. 각 지질 성분의 지방산 조성은 palmitic acid, oleic acid 그리고 linoleic acid 였으며 현염주를 제외하고는 조성상에 크게 차이가 나지 않았다.

• 한국광학회지
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• 제5권2호
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• pp.304-310
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• 1994

광섬유내에 첨가되어 있는 $GeO_{2}$등의 물질을 열확산시켜서 만드는 열확장코어 광섬유는 광섬유 복합소자에서 회절에 의한 솔실을 줄여주는 역할을 함으로써 시준과 집광을 위한 렌즈가 필요없게 된다. 광섬유의 열처리를 위하여 전기로를 제작하였으며 $1.3\mu\textrm{m}$ 단일 모드 광섬유를 $1250^{\circ}C$에서 10시간동안 열처리한 결과 모드 크기가 27% 확장되었음을 확인할 수 있었다.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 1998년도 제2회 박판성형심포지엄 논문집 박판성형기술의 현재와 미래
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• pp.140-147
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• 1998

The texture evolution by deep drawing was investigated and the lattice rotation rate was predicted using rate sensitive model with full constraints boundary conditions. The calculated textures show different behaviors with the amount of the flange deformation and initial crystal orientations. Among the crystal orientations located parallel to RD, the crystal orientations around the D component rotated toward the Cu component, the crystal orientations along the ${\alpha}$ fiber rotated toward the {110}<001> and {110}<111> components during deep drawing. In the case of the part parallel to 45$^{\circ}$ with respect to RD, the crystal orientations around the D component rotated about ND and the crystal orientations along the ${\alpha}$ fiber also rotated toward the (110)[23] and (110)[27] components about ND. In the part parallel to TD, the crystal orientations around the D component rotated toward the Rotated Cube and the crystal orientations along the ${\alpha}$ fiber rotated toward the {110}<113> component.

• 한국산업안전학회:학술대회논문집
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• 한국안전학회 2003년도 추계 학술논문발표회 논문집
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• pp.113-117
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• 2003

The reliability of machined fiber reinforced composites (FRC) in high strength applications and the safety in using these components are often critically dependent upon the quality of surface produced by machining since the surface layer may drastically affect the strength and chemical resistance of the material [1,2,3,4]. Current study will discuss the characterization of fiber pull-out in orthogonal cutting of a fiber-matrix composite materials. A sparsely distributed idealized model composite material, namely a glass reinforced polyester (GFRP) was used as workpiece. Analysis method employs a force sensor and the signals from the sensor are processed using AR time series model. The experimental correlation between the fiber pull-out and the AR coefficients is examined first and effects of fiber orientation, cutting parameters and tool geometry on the fiber pull-out are also discussed.

• Advanced Composite Materials
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• 제17권1호
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• pp.75-87
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• 2008

Aerospace structural applications, along with high performance marine and automotive applications, require high-strength efficiency, which can be achieved using metal matrix composites (MMCs). Rotating components, such as jet-engine blades and gas turbine parts, require materials that maximize strength efficiency and metallurgical stability at elevated temperatures. Titanium matrix composites (TMCs) are well suited in such applications, since they offer an enhanced resistance to temperature effects as well as corrosion resistance, in addition to optimum strength efficiency. The overall behavior of the composite system largly depends on the properties of the interface between fiber and matrix. Characterization of the fiber.matrix interface at operating temperatures is therefore essential for the developemt of these materials. The fiber fragmentation test shows good reproducibility of results in determining interface properties. This paper deals with the evaluation of fiber fragmentation characteristics in TMCs at elevated temperature and the results are compared with tests at ambient temperature. It was observed that tensile testing at $650^{\circ}C$ of single-fiber TMCs led to limited fiber fragmentation behavior. This indicates that the load transfer from the matrix to the fiber occurs due to interfacial friction, arising predominantly from mechanical clamping of the fiber by radial compressive residual and Poisson stresses. The present work also demonstrates that composite processing conditions can significantly affect the nature of the fiber.matrix interface and the resulting fragmentation of the fiber.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 1996년도 춘계학술대회논문
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• pp.73-80
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• 1996

Commerical purity aluminium , copper and STS 304 stainless steel sheets are welded by ultrasonic welding. The microstructures, x-ray diffraction profiles of planes , pole figures of the surface of original metal sheets are compared with those of the weld interface. The microstructures show disturbance and dark areas in the weld interface and grain refinement in the vicinity of the interface. The x-ray diffraction intensity of each plane in weld interface decreased in all metal sheets with exception of 9200) in steel sheet. The microstructure and x-ray diffraction intensity is affected by the mixture of deformation, heating and vibratin duringthe ultrasonic welding. Therefore, after the ultrasonic welding, the positions of the peak intensity in the pole figures are changed, the value of the maximum pole intensity is decreased in Al, is increased in copper and stainless steel. Very strong {100} <001> texture, strong {100} <001>,{123}<634> textures in original Al surface are transformed into weak, {100}<001>, {110}<112> and {112}<111> components in weld surface, weak (110) fiber is slightly changed to (110) fiber in copper, (100)and ${\gamma}$ fiber components are transformed into strong ${\gamma}$ fiber component in stainless steel.

• 펄프종이기술
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• 제45권5호
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• pp.30-36
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• 2013

Hydrophobic property of Kapok fiber was investigated by sequential removal of its components by different extraction methods. Acetone extraction for the removal of the hydrophobic extractives, holo-cel-lulose preparation after the removal of lignin and xylan extraction by potassium hydroxide was applied. The degree of hydrophobicity of each samples were measured by the water sorption ability. The water sorption ability of Kapok fiber was increased by the sequential treatment of acetone extraction, holocellulose preparation and xylan removal. Based on holocellulose compositional analysis by $^1H$-NMR spectroscopic method, the unusual high amount of the acetyl groups in the holocellulose of Kapok partially contributed to the hydrophobicity of Kapok holocellulose fiber.

• Computers and Concrete
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• 제8권6호
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• pp.735-755
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• 2011

The capability of a multi-directional fixed smeared crack constitutive model to simulate the flexural/punching failure modes of fiber reinforced concrete (FRC) laminar structures is discussed. The constitutive model is implemented in a computer program based on the finite element method, where the FRC laminar structures were simulated according to the Reissner-Mindlin shell theory. The shell is discretized into layers for the simulation of the membrane, bending and out-of-plane shear nonlinear behavior. A stress-strain softening diagram is proposed to reproduce, after crack initiation, the evolution of the normal crack component. The in-plane shear crack component is obtained using the concept of shear retention factor, defined by a crack-strain dependent law. To capture the punching failure mode, a softening diagram is proposed to simulate the decrease of the out-of-plane shear stress components with the increase of the corresponding shear strain components, after crack initiation. With this relatively simple approach, accurate predictions of the behavior of FRC structures failing in bending and in shear can be obtained. To assess the predictive performance of the model, a punching experimental test of a module of a façade panel fabricated with steel fiber reinforced self-compacting concrete is numerically simulated. The influence of some parameters defining the softening diagrams is discussed.

• 혜화의학회지
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• 제14권2호
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• pp.107-112
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• 2005

Peripheral axons in vertebrate animals can regenerate after nerve injury and accomplish its functional recovery. Numerous studies have revealed that diverse molecular factors are induced during axonal regeneration and their potential roles in axonal regeneration have been studied. Examples is N-CAM, L1, P0, nerve growth factors, GAP-43 and so forth. However, most of the studies on axonal regeneration have been primarily focused on axon fiber regrowth and elucidating molecular factors, and relatively less is known about functional recovery. Also, specific drugs or drug components used in the oriental medicine in relation to nerve fiber regeneration have not been known. And thus, in the present, a study on the effect of Samul-tang components and Samul-tang extracts to regeneration of peripheral axon fiber is underway by immunofluorescence staining. Therefore, this prior application of Samul-tang with documents consideration is reported with a plea for further investigation.