• Journal of the Korean Society for Nondestructive Testing
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• v.32 no.3
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• pp.269-275
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• 2012

Carbon-fiber reinforced plastic(CFRP) laminates made of nano-particle-coated carbon fibers and damaged by a simulated lightning strike were tested under compression-after-impact(CAI) mode, during which the damage progress due to compressive loading has been monitored by acoustic emission(AE). The impact damage was induced not by mechanical loading but by a simulated lightning strike. Conductive nano-particles were coated directly on the fibers, from which CFRP coupons were made. The coupon were subjected to the strikes with a high voltage/current impulse of 10~40 kA within a few ${\mu}s$. The effects of nano-particle coating and the degree of damage induced by the simulated lightning strikes on AE activities were examined, and the relationship between the compressive residual strength and AE behavior has been evaluated in terms of AE event counts and the onset of AE activity with the compressive loading. The degree of impact damage was also measured in terms of damage area by using ultrasonic C-scan images. The assessment during the CAI tests of damaged CFRP showed that AE monitoring appeared to be useful to differentiate the degree of damage hence the mechanical integrity of composite structures damaged by lightning strikes.

• Journal of The Korean Association For Science Education
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• v.14 no.1
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• pp.24-33
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• 1994

This study is aimed at categorizing the CAl programs through analyzing the 82 science CAl programs developed by KEDI( Korean Educational Development Institutes ) and the 19 science CAl programs developed by the teachers who won the prizes in the first national educational software contest. The findings are as follows. 1) The main types of science CAl programs developed by KEDI are hybrid design type of tutorials and simulations, tutorials, and hybrid design type of instructional games and drill and practice. The other type of programs are very few. 2) The main types of science CAl programs developed by the teachers, who won the prizes in 1st educational software contest, are tutorials and hybrid design type of tutorials and simulations. There is no other type of programs except only two simulation type programs. 3) The science CAl programs developed by KEDI as well as by teachers who won the prizes in the contest are biased in two or three types, and the trend is severe in the programs developed by the teachers.

• Proceedings of the Korea Information Processing Society Conference
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• 2000.10b
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• pp.1337-1340
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• 2000

정보화 사회에서의 컴퓨터의 가치는 교육분야서 더욱 높아지고 있으며, 기존의 수업보다 시간적 공간적 제약을 덜 받게 되는 원격교육은 무한한 발전 가능성을 가지고 있다. 하지만 기존 웹 상에서의 원격교육에서는 필수의 강의가 끝나면 수업의 평가 후 학생에게 수업의 결과를 알려주는 형식이었고, 또한 학습자에게는 일률적으로 평가가 적용 학생의 수준에 맞는 수업을 할 수가 없었으며 교수의 입장에서도 학생들의 평가 결과가 수업의 질을 높이거나 내용을 변경시킬 근거가 될 수 는 없었다. 따라서, CAI(Computer Aided Instruction) 시스템에서 수준별 학습을 위한 단계별 예비 테스트와 학습 후 테스트의 평가 내용을 다양한 방법으로 가시적으로 제시함으로써 교수 방법을 지원할 수 있는 평가 컴포넌트를 작성하고자 한다. 이는 평가의 방법이 체계적으로 되고 또한 학습의 패러다임을 바꾸거나 과목을 변경할 경우 또한 그 결과에 따라 교수 방법의 변화나 수업내용의 변경을 하려할 때 용의하게 사용할 수 있다. 또한 유사한 다른 패러다임의 원격교육 시스템에서도 이미 개발된 구성요소를 사용함으로써, 사용의 용이성과 이식성, 재사용성을 높일 수 있게 한다.

• The Journal of Korean Physical Therapy
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• v.28 no.6
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• pp.376-380
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• 2016

Purpose: This study was to investigate the short-term effects of spiral taping (ST) on performance on the star excursion balance test (SEBT) in individuals with unilateral chronic ankle instability (CAI). Methods: This study was single-group pre - post measures experimental design. The subjects with CAI were 39 (range, 20-31 years; male 16, females 23) were enrolled in the study. The discomfort had in unilateral ankle and Cumberland ankle instability score was 19.56 (${\pm}3.29$). Spiral tape (a width of 3 mm) was applied $3{\times}4$ cross shape on medial malleolus, lateral malleolus and dorsal of talocural joint of unstable ankle. SEBT was measured baseline and 30 min later in stable ankle and unstable ankle. Results: SEBT showed significantly improved after applying the ST (p<0.05, ES=0.74) on unstable ankle. In comparison the difference of stable and unstable ankle, between the pretest and posttest were significant differences (p<0.01, ES=1.88). Conclusion: These results indicated that ST improves performance on the SEBT. Therefore, it suggests that ST may be a suitable intervention to dynamic balance in patients with CAI.

• Asian-Australasian Journal of Animal Sciences
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• v.23 no.8
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• pp.1034-1042
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• 2010

This study aimed to determine the optimum dietary crude protein level in a typical diet for fattening pigs fed ad libitum under normal climate conditions in Central Vietnam. One hundred and ninety two gilts of Mong Cai local breed (MC), $F_1$ Large White${\times}$Mong Cai and $F_2$ crossbreds of (Landrace${\times}$Mong Cai)${\times}$Large White were used. At the start of the experiment, Mong Cai pigs weighed 12 kg at 11 weeks of age, $F_1$ pigs 12.1 kg at 8 weeks of age and $F_2$ pigs 12.2 kg at 8 weeks of age. Four diets differing in crude protein (CP) content (10.1, 13.1, 16.1 and 18.9% in DM) were formulated from rice bran, corn meal, cassava meal and fish meal. Calculated digestible energy content of the diets ranged from 13.5 to 13.8 MJ per kg DM. Pigs were housed individually in pens of $2.5\;m^2$ each and had ad libitum access to feed in a trough as well as water in bowls. The final weights after a growing period of 150 days were 66, 86 and 96 kg for MC, $F_1$ and $F_2$, respectively. Feed intake of MC pigs was highest at 13.1% CP while $F_1$ and $F_2$ had the highest feed intake at 16.1% CP. The results showed that for MC the maximum gain was obtained at levels between 13 to 16% CP. For the $F_1$ the maximum gain was at dietary protein levels of 16-17%. For $F_2$ the max gain was obtained at CP levels of 16 to 18%. Feed conversion was highest in MC pigs (~4.0) followed by $F_1$ (~3.3) and $F_2$ (~3.1), and within genotypes was lowest at the optimum CP level (p<0.05). Back fat thickness in MC (33.1 mm), $F_1$ (23.0 mm) and $F_2$ (20.5 mm) pigs was different and within genotypes was the lowest at intermediate CP levels. In conclusion, increasing the dietary crude protein contents in practical diets for pigs in Vietnam can increase production on small holder farms. Optimal performance for MC, $F_1$ and $F_2$ pigs is achieved at different dietary crude protein contents.

• Journal of the Korean Society for Nondestructive Testing
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• v.31 no.1
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• pp.62-67
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• 2011

Nanoparticles-coated and impact-damaged carbon-fiber reinforced plastics(CFRP) laminates were tested under compression-after-impact(CAI) mode and the propagation of damage due to compressive loading has been monitored by acoustic emission(AE). The impact damage was induced not by mechanical loading but by a simulated lightning strike. CFRP laminates were made of carbon prepregs prepared by coating of conductive nano-particles directly on the fibers and the coupons were subjected to simulated lightning strikes with a high voltage/current impulse of 10~40 kA within a few microseconds. The effects of nano-particles coating and the degree of damage induced by the simulated lightning strikes on the AE activities were examined, and the relationship between the compressive residual strength and AE behavior has been evaluated in terms of AE event counts and the onset of AE activity with the compressive loading. The degree of impact damage was also measured in terms of damage area by using ultrasonic C-scan images. From the results assessed during the CAI tests of damaged CFRP showed that AE monitoring appeared to be very useful to differentiate the degree of damage hence the mechanical integrity of composite structures damaged by lightning strikes.

• Journal of Korean Society of Transportation
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• v.22 no.3 s.74
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• pp.7-16
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• 2004

The purpose of this study was to find the characteristics of travel behavior and accessibility in terms of spatial structure. We analyzed travel behaviors and accessibility using a mode choice model and the Complementary Accessibility Index(CAI). The urban spatial structures that were compared were a compact city (CC) versus a sprawled city (SC), and high residential density districts (HD) versus low residential density districts (LD). First, CC and HDs residents had a shorter commuting distance than the CC and LDs residents. Second, behavior models showed that the use of Private cars for commuting in SCs was found to be greater than private car use in CCs, and that public transportation modes would be encouraged in CCs. Third, changes associated with the time and cost of commuting by private car generally affect the demand for public transportation modes in the CC. Also, analysis of cross elasticity suggests that changes of subway travel time affect the demand for buses very elastically. Fourth, the CAI of SC and LD were superior to the CC and HD even though the SC inefficient urban forms in terms of spatial structure. So, the spatial distribution of population density was also found to be an important factor affecting accessibility and energy savings.

• 한국생물공학회:학술대회논문집
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• 2003.10a
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• pp.9-10
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• 2003

• Proceedings of The Korean Society of Health Promotion Conference
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• 2003.05a
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• pp.81-98
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• 2003

• The Mathematical Education
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• v.30 no.2
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• pp.107-123
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• 1991