• The Transactions of the Korean Institute of Electrical Engineers A
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• v.50 no.1
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• pp.38-44
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• 2001

For double-circuit transmission line systems, an accurate digital distance relaying algorithm immune to the reactance effect is proposed. The apparent impedance calculated by the distance relay is influenced by the combined reactance effect of the fault resistance and the load current as well as the mutual coupling effect caused by the zero-sequence current of the adjacent parallel circuit. To compensate the magnitude and phase of the estimated impedance, this algorithm uses phase angle difference between the zero(positive) sequence of the both side of the system seperated by the fault point. The impedance measuring algorithm presented used a current distribution factor to compensate mutual coupling effect instead of the collected zero-sequence current of the adjacent parallel circuit.

• Proceedings of the KIEE Conference
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• 1998.07a
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• pp.384-386
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• 1998

In the emergency case such as a single line operation in a double line section because of a line broken or train's mal-operation, single line equipments that can operate without a line indication are needed. The main purpose of this study is to verify and analyze the availability of the single line operation that is able to operate without the indication of up or down line, and to offer a realizably alternative method to improve this situation. In order to carry out this study, we concentrated on getting related information. And to adopt the single line operation to existing line, the technology survey of other countries signalling system and the technical analysis of the interior signalling equipment were performed. As a result of this study, the required system and effect of the single line operation system were represented.

• Journal of the Korean Society of Clothing and Textiles
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• v.25 no.6
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• pp.1100-1111
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• 2001

The purpose of this study was to develop fashion On-line store attributes for fashion On-line shopping mall and to identify significant On-line store attributes, influencing consumers'purchase intention of interned fashion product shopping. A questionnaire was administered to 456 adults who had purchasing experience at fashion On-line shopping mall. SPSS 9.0 package was used for data analysis. Factor analysis, $X^2-test$, t-test, frequency, percentage, one-way ANOVA, multiple regression analysis were utilized. The results were as follows; 1. The On-line store attribute dimensions of fashion On-line shopping mall were tangibility, variety, marketing promotion, responsiveness, reputation, price and convenience. 2. The purchase experienced consumers showed higher purchase intention of Internet fashion product shopping and highly perceived about all sub-factors, except reputation. in On-line store attributes that have significantly positive influence on fashion On-line shopping attitudes. The purchase experienced consumers showed more favorable attitudes toward Fashion On-line shopping than non purchase experienced consumers. Attitudes toward Fashion On-line shopping have directly impact on purchase intention of Internet fashion product shopping.

• The Research Journal of the Costume Culture
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• v.19 no.3
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• pp.597-611
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• 2011

The purpose of this study is to propose a design method for one-piece dress patterns with high body fitness through an appearance evaluation of one-piece dress patterns with the application of the 3D Virtual Clothing System known as i-designer. Measures consisted of an optical illusion effect in visual imagery and mutual influence according to a change in the length and princess line, in a silhouette of a one-piece dress. The data was assessed by a t-test and a multi-way ANOVA and factor analysis using SPSS 17.0. The results were as follows; The design of the study pattern was done by modifying the ease of the bust circumference, ease of the abdominal circumference, ease of the hip circumference, the position of the side seam line, and the appearance of horizontality in the hem line, which received a low evaluation in appearance evaluations of a one-piece dress pattern. As a result of analyzing the visual image according to a change in the length and princess line, in the form of a silhouette of a one-piece dress, four factors were selected; the whole-body optical illusion factor, the upper-body optical illusion factor, the bust optical illusion factor, and the lower-body optical illusion factor. As a result of analyzing the effect of the interaction in the visual image according to the design variables, the influence of the main effect was found to be great in each factor. In the upper-body optical illusion factor, a significant difference was not noted in the two-way interaction between the length and the princess line. However, the influence on three-way interaction among the length, princess line, and silhouette was significant.

• The Journal of the Korea Contents Association
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• v.12 no.3
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• pp.487-497
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• 2012

The purpose of this study is to increase the level of learning achievement and satisfaction by developing of on-line learning instruments. This study was to investigate the relationship among learning instrumments(lecture, homeworks, on-line interaction and off-line interaction), learning achievement and learning satisfaction. This survey was conducted 226 responses of e-learning social welfare education learners. Research method used Amos 18. Result indicated that homeworks and off-line interactive instruments had a positive effect on learning achievement and satisfaction. And lecture had a positive effect on learning satisfaction, but on-line mode interaction instruments had no effect. In order to improve the effectiveness of learning, structural development of activity learning instrument is necessary. And to foster learning satisfaction, it will be necessary to increase the learning achievement.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.26 no.2D
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• pp.225-231
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• 2006

On-line shopping allows consumers to order goods via internet and receive them at homes or workplaces. Emergence of online shopping industry has brought the changes in the structure of freight industry, in the location selection pattern of industrial clusters and in the consumer's travel pattern. This trend is likely to continue, especially in Korea, as the society sees increases in women's participation in workforce, in population of the elder and in production pattern of manufacturing individually customized goods. Despite on-line shopping's heavy influence on travel demand, no study on this particular topic has been done yet, and thus the effect of on-line shopping on travel demand has not been properly reflected on policy making process. This paper suggests the transportation strategy to cope with this change based on the analysis of the effect of on-line shopping on personal travel demand.

• Strategy21
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• s.44
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• pp.291-322
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• 2018

This research aims to cast light upon security characteristics of the Peace Line, which have been underestimated. To understand maritime order and maritime security policy of the Republic of Korea between 1950 and 1970, it is necessary to analyze the Peace Line as line of defence and to investigate its character This research begins with analyzation of historical facts and investigation on security characteristics of the Peace Line. It goes further to examination of legal justification of the Peace Line, which was one of international legal issues of the period, principally regarding its security characteristics. As results of the study, it could be said that the security characteristics of the Peace Line was the line of defensive waters, which set its goal mainly to prevent infiltration of communist spies. The Peace Line had practical effect as it functioned as a base line of the ROK Navy to take anti-spy operation. At the early phase of the Korea-Japan Negotiation, the Korea delegation interpreted significance of the Peace Line passively. After abrogation of Clark Line, the delegation, however, became positive to maintain the Peace Line and its security characteristics. Security characteristics of the Peace Line was recognized again, as it became the base line of special maritime zone which was made in 1972. Through analysis on international law, it is concluded that the Peace Line was fair as a part of the right of self-defense against indirect aggression. North Korea attempted indirect aggression mainly from sea way, and these might undermine peace and cause urgent and unjust damage on the ROK. Thus the ROK's action of anti-spy operation through the Peace Line can be justifiable as considering the right of self-defence. Also the Peace Line accorded with principles of necessity, immediacy and proportionality. As it was argued on the above, the Peace Line as line of defence was one of the most significant factor in the ROK's maritime security history from the Hot war against communist forces to Cold war period after Korean War and must not be underestimated.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.30 no.6 s.249
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• pp.631-636
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• 2006

In this study, a model of pneumatic cylinder position control system considering dynamic characteristics of transmission line is proposed. The transfer characteristics of transmission line are assumed to be second order transfer function because the effect of resonance characteristics of transmission line under high frequency range can be neglected by the friction force and low pass characteristics of the pneumatic cylinder driving system. Therefore, the position control system including transmission line can be modeled by using a model of pneumatic cylinder driving system and the model of transmission line. The effectiveness of the proposed model is proved by comparison of simulation results using proposed model with experimental results.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.6 no.4
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• pp.344-353
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• 1994

This study numerically analyzed the dynamic characteristics of the frequency response on the pneumatic transmission line with load impedances. The pressure transfer function is represented by the distributed parameter line model. To validate the mathematical approximations of Bessel function ratios, the results of frequency response in a blocked line were compared with those obtained by the Infinite-product, Brown's and Square-root approximations. Special emphasis was given to the frequency response characteristics on the pneumatic transmission line with load impedances. Computations were carried out for the wide range of parameters in terms of load capacitance ratio and load resistance ratio. The present results indicated that the theoretical model is capable of accurately predicting the frequency response characteristics for any configuration of a fluid transmission line.

• Journal of the Korean Institute of Telematics and Electronics
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• v.22 no.6
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• pp.63-70
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• 1985

In this paper, the Unilateral Fin-line structure and the I-Plane structure are analysed by Rayleigh-Ritz variational method including the effect of conductor thickness. And a com-putcr-aided design program, CADUNI, is developed for microwave I-plane and Unilateral Fin-Line bandpass filters. Unilateral Fin-Line Filters are desigied at the center frequency of 10.5 GHz with guided bandwidth between 5% and 24.6%. Measured insertion loss is between 0.17 and 0.25 dB, and center frequency deviation is less than 0.2%. Experimental results are in good agree-ment with theory.