• Journal of Power Electronics
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• v.11 no.1
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• pp.105-111
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• 2011

By having accurate knowledge of the magnetic field distribution and the thrust calculation in linear synchronous motors, assessing the performance and optimization of the motor design are possible. In this paper, after carrying out a performance analysis of a single-sided wound secondary linear synchronous motor by varying the motor design parameters in a layer model and a d-q model, machine single- and multi-objective design optimizations are carried out to improve the thrust density of the motor based on the motor weight and the motor efficiency multiplied by its power factor by defining various objective functions including a flexible objective function. A genetic algorithm is employed to search for the optimal design. The results confirm that an overall improvement in the thrust mean, efficiency multiplied by the power factor, and thrust to the motor weight ratio are obtained. Several design conclusions are drawn from the motor analysis and the design optimization. Finally, a finite element analysis is employed to evaluate the effectiveness of the employed machine models and the proposed optimization method.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2011.06a
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• pp.1299-1300
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• 2011

• KSCE Journal of Civil and Environmental Engineering Research
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• v.34 no.5
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• pp.1489-1504
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• 2014

This paper is aimed to suggest a site specific partial safety factor of offshore wind turbine (OWT) pile foundation design for the offshore wind turbine complex at a West-South mainland sea in Korea. International offshore wind design standards such as IEC, GL, DNV, API, ISO and EUROCODE were compared with each partial safety factor and resistance factor. Soil uncertainty analysis using a large number of soil data sampled was carried out, and their results were adapted to estimate partial safety factor of OWT pile foundation through reliability analyses. The representative partial safety factor has been estimated as 1.3. When a proposed partial factor is willing to use to other sites, it is recommended that further studies on code calibration are required to validate their accuracy using more site characterization data.

• Korean Journal of Human Ecology
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• v.23 no.3
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• pp.501-514
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• 2014

In this study, visual images were analyzed with the representative seven kinds of selected skirts, by the differences of shape and length which are affecting to the images of skirts. In addition, the purpose of the study is to present the basic data for the skirt design and patterns those are appropriate to the preferred images of 20-30s. The results of this study are as follows. First, analyzed by the visual evaluation about the composing factors are as follows. Factor 1 is a Cute image factor, factor 2 is a charming image factor, factor 3 is a transversal factor, Factor 4 is active image factor, Factor 5 was classified as a longitudinal factors. Second, analyzed by the visual evaluation according to the shape and length of the skirt, 20-30s women's most preferred form of the skirt is pleated skirt which was highly evaluated looks good, beautiful, favorite, attractive factors. Non-prefered skirts are gored skirt which was highly evaluated not corny, not pretty, heavy, unattractive factors and gored skirt which was negatively evaluated with classic and dislike factors. In the length of skirt, the knee length short skirt is attractive, active and positively evaluated by the 20-30s women than long skirt. Therefore, the results of this study, there are almost no differences according to the age groups of 20-30s women. They are more affected from the length of the skirt rather than the shape.

• The Journal of Information Systems
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• v.11 no.1
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• pp.51-74
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• 2002

The purpose of this study is to empirically investigate critical success factors for effective implementation of web-based distance learning system. First of all, four critical success factors are theoretically derived from reviewing previous research. They are: (1) learner-related factor including the variables such as teaming ability, learning attitude, and attending motivation, (2) environmental factor including the variables of physical and mental support for learners, (3) instructional design factor represented by one variable, the degree of appropriateness of learning contents, and (4) the factor concerning the level of self-directed learning readiness embracing the variables such as curiosity for learning, openness towards challenge of learning and affection for learning. Subsequently, the relationships between these four critical success factors and the degree of learning satisfaction are empirically investigated. The data for empirical analysis of the research are collected from 1,020 respondents who have already passed the web-based distance learning courses which have been implemented in Information and Communication Officials Training Institute. Out of 1,020 responded questionnaires, 875 data were available for statistical analyses. The main results of this study are as follows. Firstly, the most important factor for successful implementation of the web-based distance learning system is shown to be the instructional design factor, and in the next place, the self-directed learning readiness factor, the environmental factor and the learner-related one in sequence. Secondly, additional analysis of the variables included in the instructional design factor shows that availability of practical information and knowledge is the most influencing variable, and next, interesting composition of contents, reasonable learning amount, optimal level of instruction, and understandable explanation are significantly important in the descending order. Lastly, among learning motivators, strong intention of acquiring business knowledges and skills is found to be the most important satisfier in the web-based distance learning. The theoretical contribution of this study is to derive a comprehensive model of critical success factors for implementing the web-based distance learning system. And, the practical implication of this study is to propose efficient and effective guidelines for developing and operating the web-based distance learning system in the various kinds of organizations.

• Journal of the Korea Fashion and Costume Design Association
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• v.9 no.3
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• pp.115-132
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• 2007

The purpose of this research is that to study of musical performer's purchasing behavior, satisfaction and design preference, and to give the information for better performance costume market based on that result. The target for the survey is limited only for above 4th grade female students and have experienced more than three times of performances. Total 364 questionnaires are used for this research. The SPSS was used for the analysis. The results were, first, in the survey of place of purchasing, specialty shop for musical performance shop was the most. The most group for the budget that they spent was under 100,000 Won. Rational price for costume would be 150,000-300,000 Won. Most people purchase costume before 2 weeks and compare 3-4 stores mostly. There were not many complaints about being comfort for costume itself. The preference for costume was different depends on not only scale of performance but also whether solo, duet or trio or more. Also harmony with other person costume was most consideration factor when they perform duet or more. For the choice of shop factor following were considered the most important; various selections, kindness of sales persons and possibility for trying various costumes. However, locations of shop or delivery service were not important relatively. For the choice of costume factor, design color, comfort and functionality were considered the most important but price, quality and decoration were not. For 'the satisfaction after purchase costume' factor, people's opinions, best appearance on the stage and meeting image with themselves were considered the most important. Second, on the subject for 'design preference of costume based on type of performance', people chose different color of dress depends on what types of performance. In case of solo, they prefer vivid primary color; in case of trio or more, they prefer black; in case of duet, they prefer pastel tone. As for preference of sleeve design, all of them prefer non-sleeve type.

• Journal of the Korean Recycled Construction Resources Institute
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• v.9 no.1
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• pp.100-108
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• 2021

The purpose of this study is to analyze the reliability index of a design by applying the reduction factor of the recently developed fiber reinforced high strength concrete design guideline(draft). By collecting material and member test data performed for the development of the design guideline(draft), statistical characteristics of material strength and member strength analysis equations are obtained. A simul ation that appl ies the material statistical characteristics and the member anal ysis equation of the design guidel ine(draft) is performed, and the statistical characteristics of the section strength are calculated by combining the statistical characteristics of the analysis equation. Reliability analysis was performed by applying the load combination of the domestic highway bridge design code and concrete structural code, and it was confirmed that the design that applies the reduction factor for materials and members suggested in the design guideline(draft) satisfies the target reliability index.

• Journal of the Korean GEO-environmental Society
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• v.17 no.12
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• pp.55-64
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• 2016

In this paper bearing capacity and safety margin of shallow foundation on weathered soil ground against shear failure by using current design method of allowable stress design (ASD), load resistance factor design (LRFD) based on reliability analysis and partial safety factor design (PSFD) in Eurocode were estimated and compared to each other. Results of the plate loading test used in construction and design were collected and analysis of probability statistics on soil parameters affecting the bearing capacity of shallow foundation was performed to quantify the uncertainty of them and to investigate the resistance bias factor and covalence of ultimate bearing capacity. For the typical sections of shallow foundation in domestic field as examples, reliability index was obtained by reliability analysis (FORM) and the sensitivity analysis on soil parameters of probability variables was performed to investigate the effect of probability variable on shear failure. From stability analysis for these sections by ASD, LRFD with the target reiability index corresponding to the safety factor used in ASD and PSDF, safety margins were estimated respectively and compared.

• Archives of design research
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• v.17 no.1
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• pp.163-178
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• 2004

In this study, in order to achieve the before-mentioned study purpose, the importance of developing the new product, the relationship with the design, and the design element for developing the new product were considered. In order to extract the importance of the design element which is applied to the development of the new product design, the research model about the induction of the priority was created, the evaluation items were instituted, and the demonstrative research approach was performed in order to recognize the relationship among those elements. Firstly, in the process of selecting the items for the application, 14 evaluation elements which were extracted through the advanced study data were grouped in 4 kinds of dimensions, and the properties which are related with the Digital TV product were composed up of 36 items. Through the factor analysis, by decreasing the detailed standard for the evaluation of 36 items, the parsimony was secured, and the characteristics which the various items contain induced into one factor. Secondly, the detailed factors which were united into one factor went under the paired comparison as one by one through AHP again, and then the importance degree was generated. First of all, as the first stage of AHP, the decision making factors which affect the whole achievement of purpose of the decision making were classified as in a hierarchical style. From these research results, it was known that the functional factor and esthetic factor in the process of designing the new product are the major affecting variables, and it was confirmed that in case of the Digital TV products group, the factors such as the high quality of picture, big screen, user interface, sound, product reliability, style, size, indoor reproduction, and guarantee are the main factors which influence the need of the consumers in purchasing products.

• Fashion & Textile Research Journal
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• v.12 no.5
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• pp.626-632
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• 2010

The results of the image evaluations by various shapes of skirts which are typical female's lower garment were as follows; 1. The composition factors of images by the shapes of skirts were classified into five factors. The 1st factor is lovely image factor, the 2nd is attractive image factor, the 3rd is practical image factor, the 4th is slim-looking image factor and the 5th is long-looking image factor. 2. In the 1st factor- lovely image factor, tiered skirt, $360^{\circ}$ flared skirt and $180^{\circ}$ flared skirt were evaluated to express lovely images. In the 2nd factor- attractive image factor, $180^{\circ}$ flared skirt was evaluated to express refine and attractive images. In the 3rd factor- practical image factor, $360^{\circ}$ flared skirt and gathered skirt were evaluated to express easy and practical images. In the 4th factor- slim looking image factor, males evaluated 8gored skirt and females evaluated gathered skirt to express fat images. In the 5th factor- long looking image, $180^{\circ}$ flared skirt was evaluated to express long looking images by both sexes. 3. In the lovely image factor, gathered skirt was evaluated most differently between the sexes. Both in the attractive and practical image factor, tiered skirt was evaluated most differently between the sexes. 4. In the preference of male and female university students according to the shapes of skirts, both the sexes prefered flared skirt. But the low prefered shapes of skirts were differently evaluated between the sexes; the male students' was A-lined skirt and the female's was pleated skirt and wrap skirt.