• Composites Research
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• 제19권6호
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• pp.16-22
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• 2006

다양한 조건 하에서 최상의 관통 특성을 발휘하기 위한 최적 조건에 대해 연구하였다. 섬유 종횡비(AR: 섬유 길이/섬유 직경), 계면 조건 그리고 섬유 함유량을 관통 저항력과 마찰력에 지대한 영향을 미치는 변수들로 고려하였다. 단섬유 강화고무의 관통 저항력은 기지에 비해 최대 3.4배 증가하였다. 동일한 섬유 종횡비와 섬유 함유량에서 계면 조건이 우수할수록 더 높은 관통 저항력을 보였다. 기지와 섬유 종횡비가 155이하인 일부 단섬유 강화고무의 마찰력은 존재치 않았다. 우수한 계면과 높은 섬유 종횡비를 갖는 단섬유 강화고무의 마찰력은 기지의 관통 저항력보다도 더 높았다. 전체적으로 계면 조건과 섬유 종횡비 그리고 섬유 함유량이 단섬유 강화고무의 관통 특성에 지대한 영향이 미침을 확인하였다.

• 한국식품영양과학회지
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• 제20권2호
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• pp.173-178
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• 1991

The rheological properties of acorn crude starch gel and refined starch gel were investigated by puncture test, back-extrusion test and retrogradation test. Puncture test was a useful method to compare the different gel type and concentration, and to calculate the compression and shear coefficient. Maximum extrustion force and adhesiveness were also examined by performing back-extrustion test. The retrogradation rate was analysed by Avrami equation in retrogradation test.

• 한국섬유공학회:학술대회논문집
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• 한국섬유공학회 1998년도 가을 학술발표회논문집
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• pp.283-285
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• 1998

Although many papers have been published for the mechanical properties of nonwoven fabrics, there is no report on the relationship of tensile and puncture properties. For the further applications of lightweight nonwoven products like protective clothing materials, thorough understanding of the relationship should be preceded when they are subjective to puncture farce. [1,2] (omitted)

• Composites Research
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• 제20권6호
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• pp.28-33
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• 2007

단섬유 강화고무의 관통 특성에 대해 섬유 종횡비(AR: 섬유 길이/섬유 직경), 섬유 함유량, 시편 크기 그리고 시험속도를 변수로 하여 연구하였다. 기지와 단섬유 강화고무의 관통 저항은 시편 크기의 증가에 따라 감소하였고, 동일한 시편 크기에서 시험 속도의 증가에 따라 관통 저항력은 증가하였다. 각각의 섬유 함유량에서 섬유 종횡비가 클수록 높은 관통응력 값을 보였다. 인장강도와 관통응력의 비교를 통해 시편 형상의 문제점에 대해 고찰하였다. 기지와 단섬유 강화고무의 막에 작용하는 힘은 시편의 크기에 관계없이 유사한 값을 보였고, 동일한 시편 크기에서 시험속도의 증가에 따라 증가하였다. 각각의 섬유함유량에서 섬유 종횡비가 클수록 막에 작용하는 힘은 크게 나타났다 전체적으로 시편 크기, 시험속도가 단섬유 강화고무의 관통 특성에 지대한 영향을 미침을 확인하였다.

• 한국식품조리과학회지
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• 제11권1호
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• pp.83-91
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• 1995

For the accurate interpretation and objective measurement of textural characteristics of fermented vegetables, first of all, the studies on the microstructure and chemical compositions of vegetable cell, and the changes in the textural properties of vegetables during salting, blanching and fermentation should be carried out. And the mechanical textural parameters were needed to compare with and analyze in relation to the sensory parameters. In this review, the thypical force-distance curves of fermented vegetables were obtained from the compression, cutting and puncture test. And it was showed that the compression force was a more effective textural parameter to express the hardness of fermented vegetables, and the sensory chewiness and toughness were related to the changes in cutting force. In the puncture test, the puncture force was related to the hardness and varied with the size and form of puncture probe; the changes in puncture force by small probe could express the decrease in hardness and crispness, whereas those by large probe could represent the changes in toughness. And the brittleness and crispness could be measured by the break point and the numbers of peak obtained from the force-distance curves.

• 한국식품과학회지
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• 제17권6호
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• pp.469-473
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• 1985

도토리묵의 관통검사와 Back Extrusion test를 실시하여 각각의 특징적인 force-distance curve를 구하였다. 관통검사시에 관여하는 compression force와 shear force의 기여도를 알기 위하여 $K{\acute{c}}$와 $K{\acute{s}}$를 계산하였다. 도토리묵의 관통에는 compression force가 훨씬 더 크게 기여하고, 도토리묵의 농도가 클수록 탐침의 지름이 커질수록 그 기여도가 더 증가하였다. Back Extrusion test에 의해 얻어지는 maximum Extrusion force는 시료량의 증감에는 변화가 없었지만, 도토리묵의 농도가 증가함에 따라서는 그 값이 증가하였다.

• Journal of Korean Neurosurgical Society
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• 제62권4호
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• pp.382-388
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• 2019

Objective : The primary aim of this investigation was to explore the nature of dura mater biomechanics following the introduction of puncture defect(s). Methods : Twenty-eight dura mater specimens were collected during autopsy from the department of forensic medicine of the authors' institution. Specimens were divided randomly into one of four groups : group I (cranial dura mater; n=7), group II (cranial dura mater with one puncture defect; n=7); group III (cranial dura mater with two puncture defects; n=7), and group IV (cranial dura mater with three puncture defects; n=7). Results : The mean${\pm}$standard deviation tensile strengths of the dura mater were $8.35{\pm}3.16$, $8.22{\pm}3.32$, $7.13{\pm}1.77$, and $6.94{\pm}1.93MPa$ for groups I, II, III, and IV, respectively. There was no statistical difference between all groups. A single, two or more punctures of the dura mater using a 20-gauge Quincke needle did not affect cranial dura tensile strength. Conclusion : This biomechanical study may contribute to the future development of artificial dura mater substitutes and medical needles that have a lower negative impact on the biomechanical properties of dura mater.

• 대한가정학회지
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• 제26권3호
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• pp.93-102
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• 1988

Rheological properties of cowpea and mung bean starch gels and pastes were investigated and compared with Instron Universal Testing machine and Brabender Viscometer. As the result of puncture test of gels, yield point force of mung bean starch gel was higher than that of cowpea starch gel. Compression coefficient of cowpea starch gel calculated by Bourne's equation was lower than that of mung bean starch gel. the stress relaxation test showed that viscoelastic properties of cowpea and mung bean starch gels may be represented by six element Maxwell model consisting of three Maxwell element in parallel. Cowpea and mung bean starch pastes showed bingham pseudoplastic behavior in 3, 5, 6, 7 and 8%. The consistency index in 7∼8% of cowpea starch paste were lower than those of mung bean starch paste. concentration dependence on consistency index and yield stress in mung bean starch were higher than those of cowpea starch. The yield stress of starch pastes was significantly correlated with yield point force by puncture test (r=0.996).

• 한국식품과학회지
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• 제18권5호
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• pp.364-371
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• 1986

High-ester pectin을 HCI 단독 또는 HCI 과 $NH_4OH$를 병용하여 demethylation 시킨뒤 얻어진 low-ester pectin(LM pectin)으로 gel을 제조하였다. LM pectin gel의 단단함과 강도(强度)를 측정한 결과 HCI로 처리된 LM pectin gel은 일반적으로 강도(强度)가 약하고 거칠며 탄력이 없었다. 반면 $HCl-NH_4OH$로 처리한 LM pectin gel은 텍스쳐가 부드럽고 탄력이 좋았다. 물리적 성질에 대한 LM pectin의 화학적 조성의 상관 관계에서 단단함(Sag값)에 대한 ester함량 및 분자량, 그리고 강도(强度)(puncture stress)에 대한 amide 및 ester함량 EH는 분자량 간에는 유의성 있는 관계가 밝혀졌다. 상관성이 높은 화학적 인자에서 LM pectin gel의 물리적 성질을 예측할 수 있는 관계식을 산출하였다.

• 한국식품영양과학회지
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• 제19권3호
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• pp.195-200
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• 1990

Effects of cooking time(5-30 min in a pressure cooker) and HTST air dehydratiion time(0-9min at 15$0^{\circ}C$) on physical properties of dried green peas(3% oisture content wet basis) were investigated by determining rehydration ratio rehydration curve browning reaction and puncture force, The rehydration ratio and curve of dried green peas were increased with increa-sing cooking time and HTST air dehydration time. Preheating of the green peas for 30 min in a pressure cooker or for 9 min of HTST air dehydration time prior to 6$0^{\circ}C$ air dehydration recovered a 87.3% of original moisture content of raw green peas in a boiling water for 5 min. The brownin greaction was gradually decreased up to 15 min of cooking time. Puncture pressure of rehydrated green peas treated in a boiling water for 5 min was decreased as the cooking time and HTST air dehydration time were increased and was highly correlated with rehydration (r=-0.956) The effects of cooking time and HTST air dehydration time on rehydration ratio browning reaction and puncture pressure were significantly different at the a=0.01 level except effect of HTST air dehydration time on browning reaction.