• 전력전자학회:학술대회논문집
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• 전력전자학회 2001년도 전력전자학술대회 논문집
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• pp.698-701
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• 2001

Loss analyses of two soft switching techniques for two-transistor forward converters are presented. The sums of snubber conduction and capacitive turn-on losses for two transistors are calculated to compare the losses of two techniques. While the conventional soft switching technique shows the loss difference between two transistors, proposed soft switching technique shows equal as well as lower loss in two transistors.

• 한국공작기계학회논문집
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• 제14권2호
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• pp.83-90
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• 2005

A mirror cam mechanism a kind of conjugate cam mechanism consists of two cams, two rollers, and two links. Since profiles of two mirror cam are identical, a simultaneous machining of two cams is achievable. Some machining errors on cam profiles do not result in the internal acting force, which often causes problems in high speed cam mechanism between two links. Also, since angular accelerations of two links are same, the internal acting force by the difference of the angular accelerations does not occur in the mechanism. Thus the mirror cam mechanism is very useful in high speed machinery. This paper studies a design method as well as a machining method, and develops an exclusive CAD/CAM software for mirror cam profiles. The developed CAD/CAM software is applied to a typical mirror cam mechanism and a mock-up equipment is built in order to test the machinism mirror cm. Experimental investigations show that the contact between cam surface and roller surface according to cam rotation agrees well with the simulation on the developed CAD/CAM software.

• Asian Journal for Public Opinion Research
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• 제8권2호
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• pp.144-159
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• 2020

This paper investigated the impact of grit on sustainable behavior and emotional well-being. A questionnaire about grit, sustainable behavior, and emotional well-being was administered to 273 undergraduate students in South Korea. To examine the association between the variables, this study used two spell out (SEM) comparison models. The results show that grit is positively related to sustainable behavior and emotional well-being. The effect of grit on emotional well-being was mediated by sustainable behavior. The effect of grit is higher on sustainable behavior than emotional well-being. In addition, sustainable behavior has a positive relationship to emotional well-being. The results show that the grit has an important implication for sustainable environment education and individual well-being.

• 복식문화연구
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• 제8권1호
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• pp.1-14
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• 2000

The purposed of this was (1) to investigate the beliefs, attitudes and buying intention of well-known brand apparel among female college students, and (2) to identify the factors that might distinguish those who have high intention to purchase well-known brand apparel and those who have low intention in terms of individual characteristics and social influence. The data were collected trough questionnaire from random samples of 291 female college students. Statical analysis of factor analysis, χ²-test, t-test and multiple discriminant were performed in analyzing the data. 1. 63% of 291 respondents investigated were identified as having high intention to buy well-known brand apparel. 2. Those who have high intention to buy well-known brand apparel have significantly higher beliefs on well-known brand apparel. 3. Those who have high intention to buy well-known brand apparel have significantly more favorable attitude toward buying well-known brand apparel. 4. Two groups of high intention and low intention to buy well-known brand apparel have significantly different profiles in terms of social influences, values, personality and demographic variables.

• 지질공학
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• 제17권3호
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• pp.405-409
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• 2007

예천온천지구에는 5개 온천공이 개발되어 있으며, 온천공들간의 거리는 약 $159.0m{\sim}702.6m$정도이다. 온천조사시 적정양수량 평가에 있어서는 각 공에 대한 적정양수량을 평가한 후 온천공간 수위간섭을 고려하여 적정양수량을 조절하도록 되어있다. 2호공과 5호공의 공간 거리는 약 159 m로서 5개 공중 가장 가깝게 위치하고 있으며, 양수시험시 이들간의 수위간섭 현상도 매우 크게 발생하였다. 5호공에서 3일간 양수시 5호공 자체의 수위강하는 17.21 m 이었으며, 2호공의 수위강하 역시 16.67 m로 두 공간에는 약 0.54 m 정도의 차이만을 보였다. 따라서 온천공간 영향의 정도는 약 97%로 매우 높았으며, 적정양수량도 당초 $750m^3/day$에서 $24m^3/day$로 감하였다. 또한 이와 같이 두 공간에 영향이 심한 원인은 대수층이 1.5차원에 기인한 것으로 해석된다.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2000년도 전력전자학술대회 논문집
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• pp.172-176
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• 2000

The paper presents the fault detection and isolation of two DC-DC converters parallel operation by ZCT method. Two experimental prototype converters were designed and implemented for evaluation of fault tolerant system. The experimental results show that fault detection and isolation circuit works very well.

• 성인간호학회지
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• 제15권3호
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• pp.411-421
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• 2003

Purpose: The purpose of this study is to compare spiritual well-being and perceived health status between Korean and Korean-American and to provide basic data that might develop comprehensive health care program including spiritual dimension. Method: The subject of the study were 411 adults chosen from religious organization located in Gyeongsang Province, Korea and Chicago, U.S.A.. The instruments used in the study were Spiritual Well-being Scale by Paloutizian & Ellison and Health Self Rating Scale by North Illinois University. Analysis of data was done by using descriptive statistics, Pearson correlation coefficient, ANCOVA, ANOVA and Duncan test with SPSS program. Result: 1) The mean score of spiritual well-being of Korean was 3.17 and Korean-American was 2.63, there was significant difference between two groups. 2) Perceived health status of Korean was 2.37 and perceived health status of Korean-American was 2.54, there was significant difference between two groups. Conclusion: According to this study, it is important to take into considerations spiritual aspects and cultural and environmental elements in developing the comprehensive health care program.

• 한국방재학회 논문집
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• 제9권6호
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• pp.89-97
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• 2009

본 연구에서는 도시지역을 관통하는 댐 붕괴파의 전파특성을 모의하고 분석하기 위한 선행 작업으로 천수방정식과 well-balanced HLLC 기법에 근간을 둔 2차원 비구조적 유한체적모형을 개발하였다. 개발된 모형은 다양한 1차원과 2차원의 댐 붕괴파 해석과 관련된 문제에 대해 검증되었으며, 검증결과 해석해 및 수리모형실험을 통한 실측자료와 매우 일치하는 경향을 나타냈다. 본 연구에서 개발된 수치모형은 현장에서 그리고 수리모형실험을 통해 관측된 수위자료와 잘 일치하였으며, 기존의 모형으로부터 계산된 수위결과에 비해 비교적 보다 정확한 결과를 나타내었다.

• The Journal of Advanced Prosthodontics
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• 제9권2호
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• pp.124-129
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• 2017

PURPOSE. This study evaluated the effect of span length on the adaptation of implant-supported cobalt chromium frameworks fabricated by three techniques. MATERIALS AND METHODS. Models with two solid abutment analogs at different inter-abutment distances were digitized using a laboratory scanner. Frameworks of two-, three-, and four-unit fixed prostheses were designed by a computer. Six dots with a diameter of 0.2 mm were preset on the surface of each framework. A total of 54 implant-supported cobalt chromium frameworks were fabricated by milling, selective laser melting (SLM), and cast techniques. The frameworks were scanned and exported as Stereolithography files. Distances between two dots in X, Y, and Z coordinates were measured in both the designed and fabricated frameworks. Marginal gaps between the framework and the abutments were also evaluated by impression replica method. RESULTS. In terms of distance measurement, significant differences were found between three- and four-unit frameworks, as well as between two- and four-unit frameworks prepared by milling technique (P<.05). Significant differences were also noted between two- and three-unit frameworks, as well as between two- and four-unit frameworks prepared by cast technique (P<.05). The milling technique presented smaller differences than the SLM technique, and the SLM technique showed smaller differences than the cast technique at any unit prostheses (P<.05). Evaluation with the impression replica method indicated significant differences among the span lengths for any fabrication method (P<.05), as well as among the fabrication methods at any unit prostheses (P<.05). CONCLUSION. The adaptation of implant-supported cobalt chromium frameworks was affected by the span length and fabrication method.

• 대한인간공학회지
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• 제27권4호
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• pp.73-83
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• 2008

With a rapid extension of functions in mobile phones, text input method has become very important for mobile phone users. Previous studies for text input methods were focused on Fitts' law, emphasizing expert's behaviors with one-handed text input method. However, it was observed that 97% of Korean mobile phone users input texts with two-hands. Therefore, this study was designed to develop a prediction model of two-handed Hangul text entry method including novice users as well as experts for mobile phone. For this study, Fitts' law was hypothesized to predict experts' movement time(MT) whereas Hick-Hyman law for visual search time was hypothesized to be added to MT for novices. The results showed that the prediction model was well fitted with the empirical data for both experts and novices with less than 3% error rates. In conclusion, this prediction model of two-handed Hangul text entry including novice users was proven to be a very effective model for modeling two-handed Hangul text input behavior for both experts.