• Journal of Power Electronics
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• v.12 no.1
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• pp.75-82
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• 2012

Elimination of rotor position sensors mechanically coupled with the rotor shaft is attractive to variable speed drives primarily due to increased system reliability and cost reduction. In this regard, search for a simple and robust position sensorless control has been intensified in past few years specifically for low-cost, high-volume applications such as home appliances. This paper describes a new parameter insensitive position sensorless control for switched reluctance motor (SRM) drives satisfying such a need in this market segment. Two consecutive switch-on times of the controllable switch in hysteresis current control are compared to estimate the rotor position and speed. The proposed sensorless control algorithm is very simple to implement since it does not depend on extensive computation or any additional hardware. In addition, the proposed method is robust in that its dynamic performance is least affected by system parameter variations. The proposed approach is demonstrated on a single-controllable-switch-converter-driven SRM with two-phases that lends itself to a system with low cost and compact packaging which comes close to the intended applications. Analysis and simulation results followed by experimental verification are presented to demonstrate the feasibility of the proposed sensorless control method.

• Journal of the Korean Home Economics Association
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• v.41 no.9
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• pp.55-67
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• 2003

The purpose of this study was to find out the source of information and clothing benefits of female university students according to their shopping orientations. 340 female students living in Seoul were surveyed and the following results were found: Female students were divided into recreational shoppers and convenience shoppers according to their shopping orientations. Recreational shoppers exhibited interest in self-improvement, individuality, economy, and convenience shoppers in practicality of clothing benefits. Recreational shoppers focused higher value on gathering information than convenience shoppers and prefer information they gain in store display and mass communication media. Recreational shoppers have higher value on self-actualizing than social affiliation value. The findings indicate that shopping orientation can be used effectively to segment the female university students market and the finding of this study contribute to the development of strategies for clothing producer or retailer to provide a strong means to satisfy their shoppers' needs.

• Journal of Korean Society of Rural Planning
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• v.20 no.2
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• pp.115-126
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• 2014

The purpose of this study is to segment foreign tourists who are visiting rural tourism village based on importance attributes of rural experiences tourism. From the literature review, rural experience tourism and its' importance attributes were discussed and these are, peculiar cultural experience, rural experience tourism price, food, natural scenery, accessibility, accommodation and convenient facility. On-site survey was conducted to collect the data from 8 rural tourism villages and a total of 258 useful samples were collected and analyzed. Frequent, cluster analysis, MDA, and MANOVA were performed to produce the results. The cluster analysis showed that three clusters solution was appropriate and named as moderated satisfaction group, high satisfaction group, and highly satisfaction group. The results of MANOVA showed that there were differences among the groups in terms of satisfaction and loyalty of rural experiences tourism. Theoretical and practical implications were discussed in the conclusion section.

• Archives of design research
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• v.14 no.4
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• pp.35-45
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• 2001

The origin of Minivan styled RV dates all the way back to the year 1959 when Volkswagen introduced the Microbus in Germany. But the new category of "Minivan" was made, and first used by Chrysler. This was when Chrysler revealed a new vehicle in 1982 named "Minivan". Minivan was successful in gathering the public attention with it′s multi-purpose characteristic. Ever since, many models were introduced in this category by various auto-makers around the world, which made the Minivan segment very competitive. Various Minivans were also introduced by the Korean auto-makers and these models have been finding their place rapidly in the market owing to their unique characteristics. But the reason for the growth of the Minivan category in Korea was quite different from that of other nations. Through out this thesis, the possibilities of a Minivan that can full fill the needs of a new life style of a family in the basis of various documentary records will be discussed. Ways of making roads, where bigger sized Minivans are continuously increasing, more efficient will also be considered. The main topic of this thesis will be about Minivan styled RV(Recreational vehicle) in relation to the change of Korean life style.

• Journal of Korean Neurosurgical Society
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• v.58 no.5
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• pp.401-411
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• 2015

More than 10 years have passed since lumbar total disc replacement (LTDR) was introduced for the first time to the world market for the surgical management of lumbar degenerative disc disease (DDD). It seems like the right time to sum up the relevant results in order to understand where LTDR stands on now, and is heading forward to. The pathogenesis of DDD has been currently settled, but diagnosis and managements are still controversial. Fusion is recognized as golden standard of surgical managements but has various kinds of shortcomings. Lately, LTDR has been expected to replace fusion surgery. A great deal of LTDR reports has come out. Among them, more than 5-year follow-up prospective randomized controlled studies including USA IDE trials were expected to elucidate whether for LTDR to have therapeutic benefit compared to fusion. The results of these studies revealed that LTDR was not inferior to fusion. Most of clinical studies dealing with LTDR revealed that there was no strong evidence for preventive effect of LTDR against symptomatic degenerative changes of adjacent segment disease. LTDR does not have shortcomings associated with fusion. However, it has a potentiality of the new complications to occur, which surgeons have never experienced in fusion surgeries. Consequently, longer follow-up should be necessary as yet to confirm the maintenance of improved surgical outcome and to observe any very late complications. LTDR still may get a chance to establish itself as a substitute of fusion both nominally and virtually if it eases the concerns listed above.

• Journal of the Korean Graphic Arts Communication Society
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• v.27 no.1
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• pp.107-118
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• 2009

The printing industry is getting more digitalized and integration. It has enabled the interactive information and networking from Pre-Press, Press, to the Post-Press. These are efficient management and the improved process and productivity are getting more important. Such trends improved in the functionality and automation. This paper tries to find out how technology for CIP3/4-based process may be applied and resolved. Such subject includes the domestic and international cases regarding each manufacturer's CIP3/4 technology types. Another purpose is to emphasize on the needs to establish the environment. Under this environment, it is possible to integrate network in exchangeable form through JDF standard format after CIP3/4. Based on the data from this study, it is expected to collect further substantial data which is related to the domestic printing company's CIP4 operation. It will be also possible to perform subsequent studies on the proper variables of the market segment. CIP4 stands for "International Cooperation for Integration of Prepress, Press and Post-press, it is an association of around forty international companies, mostly manufacturers of prepress, press and post-press, as well as suppliers and users. In this paper, we studied on the acting application of CIP4 workflow.

• Journal of Information Technology Services
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• v.5 no.2
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• pp.155-168
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• 2006

Software product line is a software product or a set of software system, which has common functions. We can develop a specific software product, which satisfies requirements of a particular market segment and a mission in a specific domain by reusing the core asset such as the developed software architecture through the software product line. Software development methodology based on the software product line can develop a software more easily and fast by reusing the developed software core asset. Developed countries of software technology select software product line as a core field of software production technology, and support technology development. In case of USA, CMU/SEI(Carnegie Mellon University/Software Engineering Institute) developed product-line framework 4.0 together with the industry and the Department of Defense. Europe is supporting the development of product line technology through ITEA(IT for European Advancement) program. However, industries in our country understand the necessity of software production technology based on product line concept for the purpose of increasing productivity, it is not sufficient to invest for this technology development. In this paper, we aim to construct the common architecture of software product line for production of the software product line.

• Journal of the Korean Home Economics Association
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• v.39 no.10
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• pp.55-67
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• 2001

The purpose of this study were 1) to find out the benefits sought factors and segment the customers of internet shopping mall, 2) to find out the store image factors of internet shopping mall, and 3) to analyze the internet shopping mall market using perceptual map of segmented groups. The questionnaires dealing with attribute dimension of internet shopping mall image, benefits sought, and demographic variables were selected from the previous studies or were developed for this study. The data from 319 respondents which were collected through the internet survey site was analyzed by factor analysis, cluster analysis, one-way ANOVA, and $X^2$-test. The results of this study were as follows: 1. Benefit sought by consumer in internet shopping malls was found to include six different factors: assortments of products, search efficiency, brand/fashionability, delivery convenience, promotion service and informativeness. 2. As a result of subdividing the consumers, four distinctive groups were formed on the basis of benefit factors: multi-benefit oriented group, convenience oriented group, brand oriented group and low-benefit oriented group. Demographic traits such as education and income level were proven to significantly differentiate the benefit segments. 3. In the structural components of internet shopping-malls image, product/information, service/convenience and economy were drawn from attribute dimensions. 4. 12 perceptual maps of internet shopping mall image were constructed and each ideal vector were drawn.

• Journal of the Korean Home Economics Association
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• v.48 no.8
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• pp.113-128
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• 2010

The purposes of this study were 1) to divide consumers into segments according to their consumption attitude and subjective knowledge about natural dyed products 2) to develop a profile for each segment with respect to the media types, the preferred media programs, the information sources, the lifestyle activities and the demographics. Data(n = 213) was collected using questionnaires via the internet. By cluster analysis of the consumers' attitude and their subjective knowledge about natural dyed products, four groups were identified 1) the loyal consumption group (20.1%), 2) the conditional/reluctant consumption group(36.6%), 3) the negative/reluctant consumption group(24.2%) and 4) the non purchasers(19.1%). Several characteristics of these four groups were then compared by ANOVA and chi-square statistics. The results indicated that the consumption attitude and subjective knowledge could be the criteria for segmenting the consumers and that the segmented groups had unique consumer characteristics. Implications of this study were discussed.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.19 no.2
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• pp.275-281
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• 2010

This research's goal is to process directly aspherics with big sagment and thin center thickness. If we can process directly aspherics with big sagment and thin center thickness, we think it greatly helps to reduce the time of developing optical system. We made very thin glass using diamond grinding whetstone regarding the trace of tool and the detailed drawing of tool super precisive aspherics that has 0.46mm center thickness and over $30^{\circ}$ segment, $0.1{\mu}m$ machining accuracy, 15nm surface accuracy. We think this research's result will be effective to open new market because it is applied not only cell phone optical system but also CCTV robot optical system, internet phone optical system. Also we expect to enhance the super strong brittle precisive process's possibility with super precisive processing technique that achieves 0.46mm glass center thickness as first in the world.