• Journal of the Korean Society for Precision Engineering
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• v.15 no.12
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• pp.97-105
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• 1998

The fiber oriented condition inside fiber reinforced composite material is a basic factor of mechanical properties of composite materials. It is very important to meausure the fiber orientation angle for the determination of molding conditions, mechanical characteristics, and the design of composite materials. In the work, the fiber orientation distribution of simulation figure plotted by PC is measured using image processing in order to examine the accuracy of intersection counting method. The fiber orientation function measured by intersection counting method using image processing is compared with the calculated fiber orientation function. The results show that the measured value of fiber orientation function using intersection counting method is lower than the calculated value, because the number of intersection between the scanning line and the fiber with smaller fiber aspect ratio is counted less than with larger fiber aspect ratio.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.22 no.4
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• pp.953-959
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• 1998

To investigate accuracy of intensity method for measurement of the fiber orientation distribution, fiber orientation function is calculated by drawing simulation figures for the fiber orientation as varying fiber aspect ratio, fiber area ratio, and fiber orientation state, respectively. The values of fiber orientation function measured by intensity method are compared with the calculated values of fiber orientation function. The results show that measurement accuracy of the fiber orientation angle distribution by intensity method is affected by the fiber aspect ratio when the total length of oriented fiber is same. The average gradient of fiber orientation function is 0.94 for 1000mm of the total fiber length and is 0.93 for 2000 mm when the fiber aspect ratio is over 50. Measurement accuracy by intensity method is about 94% and the reliable data can be obtained by intensity method.

• Korean journal of food and cookery science
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• v.7 no.3
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• pp.69-76
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• 1991

Recent epidemiological observations suggested beneficial effects of dietary fiber on man's health. The obsective of this study was to obtain the dietary fiber reference data of mushrooms. The dietary fiber contents of six different mushrooms (Cornellus edodes, Auricularia auriculajudae, Gyrophora esculanta, Agaricus bisporus, Pleurotus ostreatus, Collybia velutipes) were analyzed by Southgate method, modified neutral detergent fiber (NDF) method and Food Research Institute (FRI) method. Duplicate sample were used for each determination. The mean values of total dietary fiber by Southgate method, modified NDF method and FRI method were respectively $20.08\pm1.45g$/100g dry weight, $20.24\pm1.85g$/100g dry weight and $21.5\pm2.70g$/100g dry weight. The mean values of all mushroom samples by FRI method were significantly different from the mean values of the samples by modified NDF method and Southgate method. However, there was no difference in the mean values of the samples between modified NDF method and Southgate method. By Southgate method, total dietary fiber of mushrooms composed of 1.7-3.1% soluble fiber, 47.0-66.6% hemicellulose, 28.4-57.7% cellulose and 0.9-3.3% lignin. By modified NDF method, total dietary fiber of mushrooms composed of 61.8-79.1% hemicellulose, 5.4-32.9% cellulose and 4.5- l5.5% lignin. Therefore, dietary fiber contents of mushrooms were mainly hemicellulose. Our values for total dietary fiber for six mushrooms were 2~4 times higher than crude fiber in textbook.

• Journal of the Korean Society for Precision Engineering
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• v.13 no.6
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• pp.34-44
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• 1996

In order to examine the accuracy of the intensity method, the fiber orientation-angle distribution of fiber-reinforced polymeric composites is measured using image processing. The fiber orientation function is calculated from the fiber orientation measured by the soft X-ray photograph. Theoretical and experimental results of fiber orientation function are compared for the composites with different fiber contents and fiber orientations. The intensity method is used for the experimental investigation and the measured fiber orientation function is compared to the calculated one. The relations between the measured and the simulated fiber orientation functions $J{\small{M}}$ and $J{\small{S}}$ respectively are identified. For the fiber length of 1.000mm and 2.000mm, it shows that $J{\small{M}}=0.83J{\small{M}}$. However. in general. the value of $J{\small{M}}$ decreases as the fiber length increases. For GFRP composites the relations between $J{\small{M}}$ and theoretical value J show that $J{\small{M}}$=0.73J for short fiber and $J{\small{M}}$=0.81J for long fiber.

• Journal of the Korea Institute of Building Construction
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• v.2 no.3
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• pp.131-138
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• 2002

The objective of the study is to examine the characteristic correlations between reinforcing carbon fiber and interfacial adhesion agent since the interfacial adhesion strength between reinforcing carbon fiber and matrices is believed to be an essential element influencing the physical properties in carbon fiber reinforced cement composite using slurry method. The integrity of interfacial adhesion between reinforcing fiber and cement not only affects the quality of fiber reinforced cement composite but also influences to a large degree the physical properties of the cement composite when producing carbon fiber reinforced cement composite using slurry method. Having analyzed the physical properties 1.e., water content, tensile strength, flexural strength and flexural toughness of carbon fiber reinforced cement composite specimens, C-PAM(cation polyacrylamide) was determined to be an optimum interfacial adhesion agent. The study has also demonstrated that interfacial adhesion strength varies largely on the content and type of the reinforcing fiber. Judging from magnified view of the tensile shear cross-section using VMS(video microscope system), interfacial adhesion strength between reinforcing fiber and matrices is affected by the type of interfacial adhesion agent. According to the result of the experiments, C-PAM was determined to be an ideal interfacial adhesion agent when using carbon fiber in producing carbon fiber reinforced cement composite with the optimum content of carbon fiber being established.

• Fibers and Polymers
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• v.7 no.2
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• pp.191-194
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• 2006

This paper adopts nonlinear vibration method to analyze the fluctuation process of fiber movement. Based on Hamilton Principle, this paper establishes differential equation of fiber axial direction movement. Using variable-separating method, this paper separates time variable from space variable. By using the disperse movement equation of Galerkin method, this paper also discusses stable region of transition curve and points out those influencing factor and variation trend of fiber vibration.

• Journal of the Korean Ceramic Society
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• v.32 no.9
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• pp.995-1002
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• 1995

The alumina fiber was obtained by extruding the TEA complexed polymeric sol, synthesized by the alkoxide sol-gel method, through nozzle. The purpose of this study was to investigate the properties of fiber spun by TEA complexed sol. The analysis of sol indicated that TEA was bonded at alkoxide precursor and the optimum molar ratio for spinning was 0.5 mole of TEA, 3 mole of H2O. The cross section of the fiber from circular nozzle was not circular but oval, which indicated that the shape of nozzle did not affect the shape of fiber. The diameter of the fiber was about 100 ${\mu}{\textrm}{m}$ in the state of dried gel fiber, 60${\mu}{\textrm}{m}$ in calcined fiber, and the tensile strength of the fiber calcined at 90$0^{\circ}C$ was 2.1$\times$108 Pa.

• Journal of the Korean Society for Nondestructive Testing
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• v.18 no.5
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• pp.357-364
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• 1998

To investigate accuracies between intensity method and count method for measurement of the fiber orientation distribution, fiber orientation function is derived by drawing simulation figure for the fiber orientation as varying fiber aspect ratio, fiber area ratio, and fiber orientation state, respectively. The values of fiber orientation function measured by intensity method and count method are compared with the calculated ones from simulation figures. The results show that measurement accuracy of fiber orientation angle distribution obtained by count method is by 4% higher than that by intensity method.

• Korean Journal of Poultry Science
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• v.21 no.2
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• pp.73-82
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• 1994

A study was conducted to develop a new analytical method to quantitate chicken dietary fiber (CDF). Four types of grain diets and 2 types of forages were used. Three broiler chicks at eight weeks of age were used in the Latin square design to estirnate the in vivo digestibility. Six quantitative analytical methods (Southgate method, total dietary fiber or TDF, acid detergent fiber or ADF, neutral detergent fiber or NDF, crude fiber or CF) including CDF were compared in this study. ADF, NDF and CF contained the lowest amount of the unavailable carbohydrate(UC). The value of TDF was higher than the values of ADF, NDF and CF and lower than CDF and the Southgate method. The value of NDF showed the lower values than the CDF, Southgate fiber and TDF. The recovery rate of the fiber in the feces was high in the TDF, ADF, NDF and CF, while CDF and Southgate fiber showed lower recovery rates. TDF, NDF, ADF, or CF can replace chromium in the digestibility test, while the CDF and Southgate fiber can not replace chrorniurn. The digestibility of TDF, NDF, ADF and CF in the chicken showed negative values or values close to zero depending on the types of feed but the digestibility of CDF and Southgate fiber showed relatively high positive values.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.43 no.5
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• pp.34-42
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• 2011

A fiber processing method, which might be an alternative for conventional refining process, was introduced. The method consists of repetitive, gentle, mechanical impacts on fibers, followed by fiber uncurling process. This method was very effective for OCC and BCTMP for increasing WRVs (water retention value) while keeping fiber lengths from shortening. For OCC and BCTMP, gentle mechanical impacts on fibers using Hobart mixer increased breaking lengths and tear strengths simultaneously at fast drainage level, and straightening fibers using kady mill increased those strength properties further. For SwBKP and HwBKP, only mechanical impacts using the Hobart mixer were effective on increasing tensile and tear strength at fast drainage, but there were no further increase by kady mill treatment. The strength increases of BCTMP by this alternative fiber processing method were exceptionally high. An extensive engineering development should be followed to actualize this fiber processing mechanism in an energy-effect way.