• 대한전기학회:학술대회논문집
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• 대한전기학회 2003년도 추계학술대회 논문집 전력기술부문
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• pp.174-177
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• 2003

Kinds of most frequent faults happened on overhead distribution system are the single line-to-ground fault, the line-to-line fault and the two line-to-ground fault. Occasionally, the three line-to-ground fault and the disconnection of a wire are happened in severe conditions. In this study, the single line-to-ground fault, the line-to-line fault, two line-to-ground fault on three-phase four-wire overhead distribution system were experimentally simulated and characteristics of total leakage current of distribution arrester caused by these faults were investigated. Also, the changing aspect of total leakage current of distribution arrester caused by voltage variation was investigated. In a consequence, abnormal voltages caused by voltage variation, the line-to-line fault, the two line-to-ground fault have a little effect on total leakage current of ZnO arrester. But abnormal voltages caused by the single line-to-ground fault have an important effect on total leakage current of ZnO arrester.

• 한국콘텐츠학회:학술대회논문집
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• 한국콘텐츠학회 2009년도 춘계 종합학술대회 논문집
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• pp.373-377
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• 2009

본 연구는 학습자의 효과적 학습을 위해 온라인 상 콘텐츠 품질을 구성하는 요소와 오프 강의가 콘텐츠 품질을 인식하는데 얼마나 영향을 주는가를 알아보기 위한 연구이다. 다속성 태도모델(multiattribute attitude model)의 속성만족도-중요도 모델(attribute satisfaction-importance model)을 중심으로 온라인 학습에 있어 콘텐츠 품질이 학습태도에 미치는 영향과 오프 강의를 병행했을 때의 학습태도(learning attitude) 형성의 변화에 대한 관계를 살펴보고자 한다. 콘텐츠 만족도에 대한 신념(belief)은 콘텐츠 품질을 구성하는 요소로 음성강의, 동영상강의, WBI방식 강의로 나누어 평가한다. 여기에 웹상의 강의와 오프강의를 병행했을 때 형성되는 학습태도의 변화에 대해 연구한다.

• Journal of Advanced Marine Engineering and Technology
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• 제32권6호
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• pp.964-973
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• 2008

In this study, a short-wavelength coplanar-type transmission line employing periodic ground structure (PGS) was developed for application to miniaturized on-chip passive component on Si Radio Frequency Integrated Circuit (RFIC). The transmission line employing PGS showed shorter wavelength and lower characteristic impedance than conventional coplanar-type transmission line. The wavelength of the transmission line employing PGS structure was 57 % of the conventional coplanar-type transmission line on Si substrate. Using the theoretical analysis. basic characteristics of the transmission line employing PGS (e.g., bandwidth. loss, impedance, and resonance characteristics) were also investigated in order to evaluate its suitability for application to a development of miniaturized passive on-chip components on silicon RFIC. According to the results. the bandwidth of the transmission line employing PGS was more than 895 GHz as long as T is less than 20${\mu}m$, and the resonance characteristic was observed in 1239 GHz, which indicates that the PPGM structure is a promising candidate for application to a development of miniaturized on-chip passive components on Si RFIC.

• 한국정보과학회논문지:컴퓨팅의 실제 및 레터
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• 제8권3호
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• pp.295-302
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• 2002

이 논문에서는 전자화폐 시스템 사용의 기술적인 문제점에 관한 몇가지 해결방안을 제안한다. 그 해결책은 온/오프 라인 겸용 전자화폐, 원카드, 주문형 시스템, 카드 대 카드 이체 시스템 등이다. 이 대안들이 엔젤플러스 전자화폐 사례에서 소스코드로 기술되었다. 전자화폐는 IC형과 네트워크형으로 분류 한다. 그러나 그들은 통합되어야 한다 최종사용자는 편리성을 위하여 겸용으로 사용되기를 원한다. 이 논문에서는 사례연구에 의하여 온/오프 라인 겸용 전자화폐를 개발한다. 이 논문을 바탕으로 미래연구에서는 소비자지향의 다양한 기능을 소유한 전자화폐 개발이 진행되어야 할 것이다.

• 한국정밀공학회지
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• 제13권3호
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• pp.70-79
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• 1996

In off-line process optimization, process parameters are controlled such that the process is robust against changes in equipment conditions and incoming materials. The off-line methods, however, are not effective when the changes are so large that process parameters need to be adjusted. On-line control can respond to such large changes, but process uniformity has not been controlled on-line due to the difficulties in modeling. This paper is aimed at developing a new on-line control methodology where the uniformity is controlled effectively. The process variability is categorized based on the physical considerations, and the process parameters are classi- fied considering their effects on the categorized process variabilities. On-line control is performed with the properly selected process parameters so that robustness may not be degraded. The developed methodology is applied to the single wafer plasma etching processes, which resulted in both higher within-a-wafer uniformity and compens- ation of the incoming material non-uniformity.

• 한국의류산업학회지
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• 제7권5호
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• pp.501-508
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• 2005

The purpose of this study was to investigate the effects of Chinese consumer characteristics as internal inclination on the trust and purchase intention of on-line shopping mall. Two hundred sixty subjects, who were living in Shanghai, China and were university students, were randomly selected for questionnaire. The effective two hundred forty four questionnaires were used to conduct reliability tests for internal consistency and multiple regressions for relationship between independent and dependent variables with SPSS 10.0. The results from this study were as follows. It showed a significant relationship between the on-line shopping experience, consumer innovation, consumer risk and the trust of on-line shopping mall, however, it didn't show any significant relationship between convenience shopping orientation and the trust of on-line shopping mall. Also, It showed a significant relationship between the on-line shopping experience, consumer innovation and the distrust of on-line shopping mall, however, it didn't show any significant relationship between consumer risk, convenience shopping orientation and the distrust of on-line shopping mall. It showed a significant relationship between purchase intension, the consumer risk and on-line shopping experience which appeared a high trust in on-line shopping mall, however, it didn't show any significant relationship between purchase intension and consumer innovation which appeared a high distrust. Therefore, it could be concluded that in China it is decreasing to purchase through the internet shopping mall every year because the group of consumer innovation, which most of internet users in China belong to it, distrusts the internet shopping mall.

• 한국콘텐츠학회논문지
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• 제9권10호
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• pp.492-499
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• 2009

본 연구는 학습자의 효과적 학습을 위해 온라인 상 콘텐츠 품질을 구성하는 요소와 오프라인 강의가 콘텐츠 품질을 인식하는데 얼마나 영향을 주는가를 알아보기 위한 연구이다. 다속성 태도모델(multiattribute attitude model)의 속성만족도-중요도 모델(attribute satisfaction-importance model)을 중심으로 온라인 학습에 있어 콘텐츠 품질이 학습태도에 미치는 영향과 오프라인 강의를 병행했을 때의 학습태도(learning attitude) 형성의 변화에 대한 관계를 살펴보고자 한다. 콘텐츠 만족도에 대한 신념(belief)은 콘텐츠 품질을 구성하는 요소로 음성강의, 동영상강의, WBI방식 강의로 나누어 평가한다. 여기에 웹상의 강의와 오프라인 강의를 병행했을 때 형성되는 학습태도의 변화에 대해 연구한다.

• 한국의류학회지
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• 제28권3_4호
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• pp.396-402
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• 2004

The purpose of this study was to investigate the difference of cotton fabric texture perceived between on-line(screening fabric) and off-line(real fabric), and to analyze fabric characteristics having an effect on the difference. The similarity of 55 various cotton fabrics perceived between on-line and on-line were measured showing simultaneously real fabrics and screening fabrics by 7-scale questionnaire. And the characteristics of cotton fabrics such as weave structure, thickness, weight, fabric density, stiffness, Hunter's L, a, b, and hue were measured. Cotton fabrics were classified into 3 groups by extent of similarity. There were no significant differences in weft density, stiffness, Hunter's L, a, b, and hue among 3 groups. But there were significant differences in weave structure, thickness, weight, warp density, and difference of warp ＆ weft density. The fabrics having large similarity were thick and heavy, had small warp density and difference of warp ＆ weft density, and distinct surface texture. The group having medium similarity included fabrics of medium thickness and weight, having weak surface texture, large warp density and difference of warp ＆ weft density. The group having small similarity, which the differences between on-line and off-line were large, included thin and light fabrics having smooth surface and large warp density and difference of warp ＆ weft density.

• 아동학회지
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• 제25권2호
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• pp.109-120
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• 2004

This study examined the effects of Internet addiction on interpersonal relationships. The subjects were selected from 337 secondary school male students and data were collected with questionnaires. Data were analyzed with paired t-test and t-test. Result showed that there is a difference between on-line and off-line interpersonal relationships by Internet addiction. That is, internet addicted adolescents have more positive interpersonal relationships in on-line situations, while normal adolescents do not show any significant difference between on-line and off-line situations.

• 산업경영시스템학회지
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• 제3권3호
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• pp.35-39
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• 1980

Although the product line produces a large volume of goods in a relatively short time, once the product line is established there are numerous problems that arise in connection with this product line. One of these problems is the problem of balancing operations or stations in terms of equal times and in terms of the times required to meet the desered rate of production. The objective of line balancing is minimizing the idle time on the line for all combinations of work stations subject to certain restrictions. In general, there are two types of line-balancing situations : (1) assembly line balancing and (2) fabrication line balancing. Two approaches to the assembly line balancing problem have been used. The first assumes a filed cycle time and find the optimum number of work stations. The second approach to the assembly line balancing problem assumes the number of work stations to be fixed and systematically coverages on a solution which minimizes the total delay time by minimizing the cycle time. Here the cycle time is determined by the longest station time. In this paper, by using the second approach method, a general mathematical model, problem solutions, and computer program for the assembly line balancing problem is presented. Data used is obtained from the company which has been confronted with many problems arising in connection with their assembly line.