• 디지털융복합연구
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• 제19권7호
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• pp.289-301
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• 2021

이 연구는 무용전공 중·고등학생의 완벽주의 성향이 경쟁불안 및 무용몰입에 미치는 영향을 규명하는데 목적이 있다. 연구대상은 무용전공 중·고등학생 279명을 유의표집방법으로 표집하였으며 조사도구는 설문지를 사용하였다. 자료분석은 t-test, 일원변량분석, 상관분석, 다중회귀분석을 실시하여 다음과 같은 결론이 도출되었다. 첫째, 완벽주의 성향과 경쟁불안에 유의한 차이가 나타났다. 둘째, 완벽주의 성향이 무용몰입에 유의한 차이가 나타났다. 셋째, 완벽주의 성향과 경쟁불안 및 무용몰입 간에는 인과관계가 있다. 무용전공 중·고등학생들의 무용몰입을 높이기 위해서는 다양한 심리적 요인들을 탐색함으로써 무용몰입을 높일 수 있는 요인을 파악하는 것이 중요함을 알 수 있다.

• Advances in aircraft and spacecraft science
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• 제2권3호
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• pp.249-261
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• 2015

The mechanical characterization of composite materials is nowadays a major interest due to their increasing use in the aeronautic industry. The design of most of these materials is based on their stiffness, which is mainly obtained by means of tensile tests with strain gauge measurement. For thin laminated composites, this classical method requires adequate samples with specific orientation and does not provide all the independent elastic constants. Regarding ultrasonic characterization, especially immersion technique, only one specimen is needed and the entire determination of the stiffness tensor is possible. This paper presents a study of different methods to determine the mechanical properties of transversely isotropic carbon fibre composite materials (gauge and correlation strain measurement during tensile tests, ultrasonic immersion technique). Results are compared to ISO standards and manufacturer data to evaluate the accuracy of these techniques.

• 한국학교보건학회지
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• 제36권2호
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• pp.21-30
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• 2023

Purpose: The study aimed to identify factors that affect college students' learning immersion in non-face-to-face remote classes. Methods: During COVID-19, a survey was conducted on 140 college students who were taking non-face-to-face remote courses at universities located in Seoul, Gyeonggi-do, and Chungcheong-do, Korea. Data were analyzed using the Pearson correlation coefficients, Independent t-test, ANOVA, and Hierarchial stepwise multiple regression with SPSS (Windows version 27.0). Results: In the study, the most important variable influencing learning immersion was the student's self-efficacy, followed by instructor presence, class participation, lecture satisfaction, and credits. Conclusion: Instructors who teach major courses at college need to develop and apply ways to enhance learners' self-efficacy and class content that can boost learners' motivation in order to maximize learners' learning immersion. In order to facilitate learners' access to online media and maintain their interest in remote classes, passionate efforts need to be made by active instructors.

• 한국재료학회지
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• 제23권1호
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• pp.24-30
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• 2013

Today, the modification of carbon foam for high performance remains a major issue in the environment and energy industries. One promising way to solve this problem is the optimization of the pore structure for desired properties as well as for efficient performance. In this study, using a sol-gel process followed by carbonization in an inert atmosphere, hollow spherical carbon foam was prepared using resorcinol and formaldehyde precursors catalyzed by 4-aminobenzoic acid; the effect of carbonization temperature and re-immersion treatment on the pore structure and characteristics of the hollow spherical carbon foam was investigated. As the carbonization temperature increased, the porosity and average pore diameter were found to decrease but the compression strength and electrical conductivity dramatically increased in the temperature range of this study ($700^{\circ}C$ to $850^{\circ}C$). The significant differences of X-ray diffraction patterns obtained from the carbon foams carbonized under different temperatures implied that the degree of crystallinity greatly affects the characteristics of the carbon form. Also, the number of re-impregnations of carbon form in the resorcinol-formaldehyde resin was varied from 1 to 10 times, followed by re-carbonization at $800^{\circ}C$ for 2 hours under argon gas flow. As the number of re-immersion treatments increased, the porosity decreased while the compression strength improved by about four times when re-impregnation was repeated 10 times. These results imply the possibility of customizing the characteristics of carbon foam by controlling the carbonization and re-immersion conditions.

• Corrosion Science and Technology
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• 제22권6호
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• pp.419-428
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• 2023

Seawater has been used to cool devices in nuclear power plants. However, the pipes used to transport seawater are vulnerable to corrosion; hence, the inner side of pipelines is coated with an epoxy layer as prevention. Upon coating damage, the pipe becomes exposed, and corrosion progresses. The major cause is widely known as cavitation corrosion, causing the degradation of mechanical properties. In this study, corroded specimens were prepared using cavitation and immersion methods to clarify the degradation trend of mechanical properties with corrosion. Three different types of epoxy coatings were used, and accelerated cavitation procedures were composed of amplitudes of 15 ㎛, 50 ㎛, and 85 ㎛ for 2 h, 4 h, and 6 h. The immersion periods were 3 and 6 weeks. We conducted instrumented indentation tests on all degradation samples to measure mechanical properties. The results showed that higher cavitation amplitudes and longer cavitation or immersion times led to more degradation in the samples, which, in turn, decreased the yield strength. Of the three samples, the C coating had the highest resistance to cavitation and immersion degradation.

• 한국가금학회지
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• 제24권1호
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• pp.17-28
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• 1997

This experiment was carried out to investigate the effects of different chilling and packing methods on physico-chernical properties of cold-stored chicken breast and thigh meats. Dehoned chicken breast and thigh meats were chilled either air spray or ice-water immersion method. The chilled meats were either vacuum packed or atmosphere packed, and stored at -2˚C for 1, 3, 7, 11, 15, and 20 days. The pH of both immersion chilled meats and vacuum packed meats were higher than those of their counterparts(P<0.05). The pH of atmosphere packed meats increased as the storage period extended. The moisture contents of vacuum packed meats were remarkably higher than those of atmosphere packed meats. The pH of all treatments decreased as the storage period extended. The shear values of air spray chilled and vacuum packed breast meats were significantly higher than immersion chilled and vacuum packed ones. However, immersion chilled and atmosphere packed breast meats were significantly higher than those of air spray chilled and atmosphere packed breast meats. The shear values of immersion chilled and vacuum packed thigh meats were significantly higher than those of immersion chilled and vacuum packed thigh meats. In atmosphere packed thigh meats, air spray chilling method showed higher shear values than those of immersion chilled thigh meats. In thigh muscle, tenderness values tended to decrease as the storage period extended(P<0.05). Contents of water soluble proteins of vacuum packed and air spray chilled breast and thigh meats were higher than those of their counterparts as the storage period extended(P<0.05). The contents of water soluble proteins significantly decreased as the storage period extended. Salt soluble proteins of atmosphere packed breast and thigh meats were remarkably higher than those of vacuum packed ones(P<0.05). Total lipid contents of atmosphere packed and air spray chilled breast and thigh meats were higher than those of atmosphere packed and immersion chilled meats as the storage period extended. The vacuum packed meats were significantly higher in total lipid contents than those of atmosphere packed meats. The storage period decreased the total lipid contents of cold chicken, Major fatty acids in cold-stored chicken were oleic, palmitic, linoleic and stearic acids, regardless of chilling method. Unsaturated fatty acids of all treatments decreased, but saturated fatty acids increased as the storage period extended.

• 한국게임학회 논문지
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• 제17권6호
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• pp.19-28
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• 2017

최근 VR(Virtual Reality) 기술을 기반으로 하는 다양한 형태의 가상현실 콘텐츠가 개발되고 있다. 하지만 빠른 속도로 발전하고 있는 가상현실 디바이스 기술에 비해 이러한 디바이스를 적극적으로 활용하는 가상현실 기반 게임 콘텐츠 개발은 부진한 편이다. 본 논문에서는 가상현실 기술을 기반으로 하는 디바이스 중 사용자의 접근성이 높은 HMD(Head Mounted Display) 부착형 모바일 기기를 활용하여 가상현실 노래방을 두 가지 형태의 서로 다른 가상현실 재현방법론(실사기반의 3D 가상현실 공간 생성과 실사기반의 $360^{\circ}$ 영상 방식)으로 개발하고 이에 대한 사용자의 사실감과 몰입감에 대하여 사용자 테스트를 통해 비교 결과를 제시한다. 본 연구진은 논문의 비교 결과가 향후 모바일 기반 가상현실 콘텐츠 개발시 개발 지침으로 활용될 것으로 기대한다.

• 한국비블리아학회지
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• 제34권3호
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• pp.255-272
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• 2023

본 연구는 문헌정보학과 학생을 대상으로 블렌디드 러닝을 적용한 전공 교과목 운영이 학습몰입도, 결과성취도, 학습만족도에 어떠한 영향을 미쳤는지 효과를 측정 및 분석 후, 학생 중심형 수업을 보다 활성화하기 위한 시사점을 모색하기 위해 수행하였다. 그 결과 첫째, 블렌디드 러닝 수업 운영 후 학습몰입도, 결과성취도, 학습만족도의 사전 및 사후 비교분석을 통해 사후조사 평균 점수가 높은 것으로 나타났다. 둘째, 학습몰입도 요인 중 학업사유인지, 학업집중, 흥미성, 통제감 등 모든 요인에서 유의미한 결과가 나왔으며 특히 학업집중과 통제감의 효과가 높게 나타났다. 셋째, 결과성취도 요인 중 성취동기, 만족감, 관계활용능력, 수업태도 등 모든 요인에서 유의미한 결과가 나왔으며 특히 만족감과 관계활용능력의 효과가 높게 나타났다. 넷째, 학습만족도 요인은 일반만족도와 학습관련 만족도 등 모두 효과가 매우 높게 나타났다. 이로써 블렌디드 러닝을 적용한 전공 교과목 운영은 문헌정보학과 학생들에게 효과가 있다는 것으로 파악되었다.

• 한국기계가공학회지
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• 제13권2호
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• pp.108-116
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• 2014

Considering the run-out effect and cutting force coefficients, the cutting force profile of half immersion end-milling was analyzed in detail. The effects of three specific cutting-force coefficients and three edge-force coefficients are verified. Through a detailed investigation, it is proved that the radial cutting force coefficients and are the major factors which increase the cutting forces Fx and Fy in end-milling. However, the axial cutting force coefficients have no influence on the force Fx and Fy changes in end-milling. Also, the analyzed end-milling force model shows good consistency with the actual measured force with regard to Fx and Fy. Thus, this model can be used for the prediction of the force history in end-milling with run-out, and it incurs a different force history with different start and exit immersion angles as well as holding effects.

• 한국식품과학회지
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• 제21권6호
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• pp.735-741
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• 1989

For the accurate prediction of freezing time, probably the most difficult factor to measure and major error source is the surface heat transfer coefficient. In this work, surface heat transfer coefficient were determined for still air freezing and immersion freezing methods by theory of the transient temperature method and confirmed by using a modification of plank's equation to predict the freezing time of ground lean beef. The results showed the cooling rate of immersion freezing was about 11 times faster than that of still air freezing method. A comparison of surface heat transfer coefficient of copper plate and ground lean beef resulted an difference of 25-30% because the food sample surface is not smooth as copper plate. Also, when h-values measured by ground lean beef were applicated to modified model, the accuracy of its results is very high as difference of about 8%.