• Journal of Korean Society of Environmental Engineers
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• v.35 no.6
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• pp.394-399
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• 2013

The recalcitrant hairs which are accumulated in the U-trap equipped to prevent the stench from the drainage produce the phenomenon of blocking the flow of water through the home drainage pathway. The chemical dissolution solutions commercially manufactured are excessively poured into U-trap to solve this blocking problem. In this study, the specially designed instrument was developed for the experiments to cut and crush the hairs of which main component are the recalcitrant keratin proteins. The performance of the instrument for cutting and crushing hairs was investigated using experimental methods. The cutting and weighing method was used in order to obtain the average length of a large amount of hairs cut by instrument. This method is relatively simple to measure the weight of cutting hairs to obtain the average length of the fibers, the values of average length showed not greater tolerances. Also the average cutting number was defined to evaluate the performance of the cutting and crushing instruments designed for this study. We were able to apply these evaluation methods to provide the criteria to obtain the optimal structure of instrument and proper operation time in the given experimental conditions. These experimental methods and results will provide the good example to design and to analyze the various device that can be used for cutting the fibers. The cutting and crushing instrument developed in this study showed the effective abilities to cutting the hairs. The general using the cuttting and crushing instrument at every home would be helpful to prevent water environmental pollution.

• Proceedings of the Korean Fiber Society Conference
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• 1997.04a
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• pp.109-114
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• 1997

• Journal of the Korean Society for Nondestructive Testing
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• v.33 no.5
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• pp.430-435
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• 2013

This study is investigation of the characteristics for acoustic emission signal generated by destruction on glass fiber bundles and specimen that was machined composite materials surrounding the outside of GFRP cylinder. The Amplitude of acoustic emission signal gets bigger as the cutting angle of knife increases. Accordingly, the number of hits in destruction of composite materials specimen have more in longitudinal direction (longitudinal direction to the glass fiber) than in hoop direction (horizontal direction to the glass fiber) while the amplitude of signals were bigger in hoop direction than longitudinal direction. It was found out that the amplitude of the glass fiber breakage is more than 40 dB and that the amplitude of signal for matrix crack was less than 40 dB because matrix crack signal was not observed when threshold value is 40 dB and matrix crack signal suddenly appered when threshold value is 32 dB. The slope of the amplitude is related to the acoustic emission source and the slope of the amplitude of the horizontal and vertical directions are 0.16 and 0.08. In particular, The slope of the amplitude of longitudinal direction breakage appear similar to the glass fiber breakage and therefore Acoustic emission source of longitudinal direction breakage is estimated the glass fiber breakage.

• Korean Chemical Engineering Research
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• v.50 no.1
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• pp.30-34
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• 2012

For the purpose of development of polymeric material for marine applications, the effects of silica and chopped glass fiber on tensile strength of polyester resin were studied. A series of experiments were performed with different contents of silica and chopped glass fiber. Tensile strength of polyester resin was increased with the contents of unmodified glass fiber, and decreased with that of silica. The surfaces of silica and chopped glass fiber were modified with coupling agent at different concentrations, and the modification showed positive effect on the increase of tensile strength of polyester resin. Synergistic effect on the tensile strength of polyester resin was observed by modified silica and chopped glass fiber.

• Proceedings of the Korean Fiber Society Conference
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• 2003.10b
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• pp.112-113
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• 2003

한국섬유섬유산업에 있어서 섬유장에 대한 정보를 알아야 하는 이유로는 원료로부터 섬유를 분리 시키고, 길이 방향으로 배향시키며, 곧게 펼치는 과정에서 섬유의 절단을 최소화할 수 있는 기계의 조건을 산출하는데 있다. 또한 제품의 강도를 결정하는데 있어서 섬유의 길이는 중요한 역할을 한다. 그러나 섬유의 길이를 측정하는 데에는 많은 어려움이 있다. 그것은 섬유의 한올 한올의 길이를 측정하는 것은 쉽지만 수많은 섬유들을 빠른 속도로 측정해야하기 때문이다. (중략)

• The Korean Journal of Rheology
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• v.6 no.2
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• pp.147-156
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• 1994

폴리프로필렌 이산화티타늄 첨가 폴리프로필렌을 심초형 복합 방사하여 첨가제를 섬유의 중심부분, 또 표면부분에 차별분포시켰다. TiO2의 함량이 증가함에 따라 점도(η)와 저장탄성계수(G＇)는 증가하였다. 전자현미경으로 파단면의 모폴로지를 관찰한 결과 TiO2와 함량이 증가함에 따라 감소하는 경향을 보였다. TiO2의 함량 증가에 따라 강력, 절단신도, 그리고 탄성계수는 감소하였다. 복합방사한 섬유의 TiO2 함량이 2% 미만일 때는 homo PP 보다 강력이 좋아졌다. 복합 섬유의 탄성계수는 중심부에 homo PP가 분포한 경우가 더 컸 고 강력과절단 신도는 중심부에 filled PP가 분포한 경우가 더 컸다.

• Applied Microscopy
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• v.38 no.4
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• pp.347-351
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• 2008

The morphological characteristics of the cut sections of hair using razor, clipper and scissors were investigated with scanning electron microscopy. With the razor, the cutting section had a long elliptical form and a rhythmical ribbon shape. It was curved outward since the end part of it became thinner. With the scissors, the cutting section had a flat, circular form. It seemed to be because the scissors imposed a constant strength on the hair. With the clipper, the cutting section had also a circular form but a layer of the macrofibril was generated in the middle part of the cortex. It seemed to be generated while the rapidly moving blades of the clipper cut the hair in an instant.

• Proceedings of the Korean Fiber Society Conference
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• 1991.06b
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• pp.75-75
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• 1991

• Journal of the korean academy of Pediatric Dentistry
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• v.27 no.1
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• pp.151-160
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• 2000

The effect of concentration as factor in cytotoxicity, protein synthesis and alkaline phosphatase activity was compared for pulpotomy medicaments (formaldehyde, formocresol, paraformaldehyde, ferric sulfate) Human pulp fibroblasts were exposed to a range of concentrations(0.01, 0.05, 0.10, 0.25, 0.50, $1.00{\mu}l/ml$) of each agents, for period of 24hrs. The cell activities were evaluated by MTT assay, protein assay and alkaline phosphatase activity examination. The results as follows : 1. After 24hrs culture, pulp fibroblasts adding formaldehyde, formocresol and paraformaldehyde were suppressed cell activities with concentration increasing, but, no depression of cell activities by ferric sulfate. No significant difference was in formaldehyde, formocresol and paraformaldehyde. 2. Protein synthesis by pulpotomy agents were not significant difference in pulp fibroblasts but protein synthesis were a little decreased by paraformaldehyde. 3. Alkaline phosphatase activity was a little decreased by pulpotomy medicaments.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.04a
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• pp.921-924
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• 2008

Several techniques, including transmission X-ray photography and AC-impedance spectroscopy, are available for evaluating the fiber dispersion in a fiber reinforced concrete Evaluating the fiber dispersion in fiber reinfored concrete needs since the fibers bridge crackseffectively. However, these equipment is very expensive. Therefore this paper presents the quantitative evaluation method based on the image analysis of sectional image taken using an ordinary digital camera. After detecting the fiber accurately, the fiber dispersion characteristics are represented by the coefficient such as the fiber dispersion coefficient, the number of fibers in unit area, and the distribution of the fiber orientation. Test were performed to evaluate the effectiveness of proposed method and the dispersion characteristics of fibers according placing method and flow direction. Additionally, the effect of fiber dispersion characteristics on mechanical properties was investigated. Test results shows that fiber aligned along the flow direction and more fibers placed and dispersion was better on the section parallel to the flow direction. And about 50% difference in the flexural tensile strength according to the placing method occured.