• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2003.11a
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• pp.111-116
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• 2003

Recently, power-electronics equipments or machine that microprocessor is included and computers have been installed continuously in industrial process or region of electronics customer. So concern for power quality, especially sags has been increased. Because those equipments are very sensitive to sags. The sag is phenomenon that magnitude of load voltage temporarily decreases because of power system fault. If a certain equipment in industrial process have any trouble result from sag, it can cause utility to be charged for enormous economics loss. Therefore it need to analyze the characteristic of sag and then mitigation method for sags in distribution system in oder to increase reliability. This paper gives an overview of sags characteristic due to short circuit fault in distribution system and after a general discussion of the various forms mitigation, gives a sags mitigation method with concentrating on mitigation-device interface method, especially FCL that is Fault Current Limiter.

• Proceedings of the KIEE Conference
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• 1993.07b
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• pp.695-697
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• 1993

In this paper, a novel concept for a static three-phase to three-phase power converter for an AC drive with an unity power factor and reduced harmonics on the utility line is presented. The power circuit consists of two back-to-back connected six-pulse bridges having only a $5{\mu}F$ ceramic capacitor in the DC link. By controlling the active power balance between two bridges, the DC link voltage can be maintained within 20V deviation from the nominal value with the small ceramic capacitor regardless of the load variation even in the unbalanced source condition.

• Proceedings of the KSRS Conference
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• 2003.11a
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• pp.183-185
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• 2003

Spatially referenced mobile mapping (MM) images contain rich information of man-made objects , e.g. road centerlines, buildings, light poles, traffic signs ,billboards and line trees etc. Therefore, the applications in transportation, urban 3D reconstruction, utility management are implemented increasingly. It’s a fundamental issue lies in MM image process that how to orient this image in the object space including interior orientation of camera and the exterior orientation of image. In this paper, the algorithm of automatic acquirement of DC (Digital Camera) parameters based on MM images is illustrated. And then, the mapping between image space and object space for MM images is described.

• Journal of the Korean Statistical Society
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• v.19 no.2
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• pp.151-159
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• 1990

Regression diagnostics often involves assesment of the changes that result from deleting multiple cases. Diagnostic mehtodology based on global influence measure, however, needs prohibitive computing time. As an alternative, Cook (1986) developed influence approach in which it is checked whether a minor modification of specifiation influences key results of an analysis. In line with Cook's development, we propose and study an inflence derivative method that yields both the magnitude and direction of case influences. The utility of our methodology is highlighted when case influence derivatives are plotted in a lower demensional space. Such plots are especially effective in unmasking "masked" observations in least squares regression and in robust regression also. We give several illustrations.strations.

• International Journal of Advanced Culture Technology
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• v.10 no.4
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• pp.396-402
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• 2022

Since the 21st century, the internet has been an essential existence due to the 4th industrial revolution and the development of IT technology, but the focus of the existing development direction has changed a lot over the past three years. COVID-19, also known as a pandemic, first occurred in 2020 escalating rapidly and cutting off society existing as an off-line form in every country. As non-face-to-face life continues, everyday technologies using online such as hybrid work have promptly developed, and an online virtual world called Metaverse excelled and became a phenomenal topic. In this study, theoretical considerations and the current status of the metaverse, which are being highlighted as global trend keywords, are examined, and the utility of the metaverse in the fashion industry was studied. Based on this study, it is expected that the work is recognized and brings helpful intuitions as a way to revitalize the shrinking fashion industry by using the metaverse, which is still in its infancy.

• The KIPS Transactions:PartD
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• v.13D no.4 s.107
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• pp.583-592
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• 2006

Software development based on product lines has been proved a promising technology that can drastically reduce cycle time and guarantee quality by strategically reusing quality core assets that belong to an organization. However, how to measure within a product line is different from how to measure within a single software project in that we have to consider the aspects of both core assets and projects that utilize the assets. Moreover, the performance aspects of overall project lines need to be considered within a product line context. Therefore, a systematic approach to measure the performance of product lines is essential to have consistent, repeatable and effective measures within a product line. This paper presents a context-based measurements elicitation approach for product lines that reflects the performance characteristics of product lines and the diversity of their application. The approach includes both detailed procedures and work products resulting from implementation of the procedures, along with their templates. To show the utility of the approach, this paper presents the elicited measurements, especially for technical management practices among product line practices. This paper also illustrated a real application case that adopt this approach. The systematic approach enables management attributes, i.e., measurements to be identified when we construct product lines or develop software product based on the product lines. The measurements will be effective in that they are derived in consideration of the application context and interests of stakeholders.

• Korean Management Science Review
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• v.13 no.2
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• pp.25-48
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• 1996

Mixed Model Assembly Lines (MMALs) are increasingly used to produce differentiated products on a single assembly line without work-in-process storage, Usually, a typical MMAL consists of a number of (1) stations doing exactly the same operation on every job, (2) stations involving operations with different choices, and (3) stations offering operations that are not performed on every job, or that are performed on every job but with many options. For stations of the first type there is no sequencing problem at all. However, for the second type a set-up cost is incurred each time the operation switches from one choice to another. At the third type of stations, different models, requring different amounts and choices of assembly work, creates an uneven flow of work along the line and variations in the work load at these stations. When a subsequence of jobs requires more work load than the station can handle, it is necessary to help the operations at the station or to complete the work elsewhere. Therefore, a schedule which minimize the sum of set-up cost and utility work cost is desired. So this study has developed Fixed Random Ordering Rule (FROR), Fixed Ascending Ordering Rule (FAOR), Fixed Descending Ordering Rule, and Extended NHR (ENHR). ENHR is to choose optimal color ordering of each batch with NHR, and to decide job sequence of the batch with it, too. As the result of experiments, ENHR was the best heuristic algorithm. NHR is a new heuristic rule in which only the minimum addition of violations from both partial sequence and unassigned sequence at every branch could be considered. And this is a heuristic sequencing rule for the third type of stations at MMAL. This study developed one more heuristic algorithm to test the performance of NHR, which is named as Practical Heuristic Rule (PHR).

• Journal of the Ergonomics Society of Korea
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• v.34 no.5
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• pp.519-529
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• 2015

Objective: This study aims to analyze the characteristics of occupational accidents and injuries of telecommunications line and cable workers by type of workplace and operational process of cabling service and to provide baseline data in establishing the preventive policies for occupational accidents and injuries. Background: In order to set up the preventive policies for occupational injuries and illness systematically, the accident analysis by industry should be preceded. To establish more effective policies, it should be done by occupation for persons who work in various kinds of occupation rather than by industry for persons who do in the same occupation. Method: In this study, the 176 occupational accidents and injuries were classified by type of workplace - indoor (inside building) and outdoor (at the top of utility pole, in a manhole, or in the fields) - and also done by operational process involved at the time of the accident. By analyzing the characteristics of occupational injuries and illness by type of workplace and operational process, respectively, this study can be helpful in establishing the preventative policies for occupational accidents and injuries. Results: The characteristics of occupational accidents and injuries by type of workplace showed that there were differences in terms of accident rate between indoor and outdoor on age of the injured, while not on employment-size and work experience of the injured. In addition, the characteristics on accident type, agency of accident, parts of body affected, and operational process between indoor and outdoor workplaces were statistically different each other. Conclusion and Application: The findings of occupational accidents' characteristics can be applied to the establishment of systematic preventative policies for occupational accidents of telecommunications line/equipment workers.

• Fashion & Textile Research Journal
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• v.19 no.4
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• pp.385-399
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• 2017

This study will broaden the application of doll costume product with historical characteristics and the image of unlined cheollik in the $17^{th}$ century period of transition during the Joseon Dynasty. Historical design sources were extracted from old documents and precedent studies. Unlined cheollik of Shin Gyeong-yu, meritorious retainer, were selected as main reference-relic because of various fabric, preserved conditions and definite shape. 'Baby doll' was selected as main model because of consumer preferences and awareness. Design sources from unlined cheollik in the early $17^{th}$ century were about a 1:2 ratio of upper and under parts, removable separated doori-somae, knife-shaped collar (outside), projected square collar (inside), long pleats line, side slit, traditional flat fell seam sewing. Trapezoidal side line, round waistline, and thin fabric were applied in designs because of toddler-body of doll model. Three designs were produced in step 1: Cheollik A focusing on the historical remake (traditional type), Cheollik B with belt and side slit (crossover type), and Cheollik C with back- opening (modern type). In step 2, interview with fashion major student was conducted to increase the utility of designs. As a result, modern trend sources (frill, velcro, round armhole line, slope of sleeves, and floral pattern) were reflected in Cheollik B, C. Finally, three doll cheollik and cheollik-styled doll apron sample were produced. Various versions must be suggested in the study of doll costume products with traditional sources that balance historical characteristics and practicality to improve customer satisfaction.

• Biomedical Science Letters
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• v.13 no.4
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• pp.273-278
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• 2007

Stem cells have been the subject of increasing scientific interest because of their utility in numerous biomedical applications. Stem cells are capable of renewing themselves; that is, they can be continuously cultured in an undifferentiated state, giving rise to more specialized cells of the human body. Therefore, stem cells are an important new tools for developing unique, in vitro model systems to test drugs and chemicals and a potential to predict or anticipate toxicity in humans. In the present study, in vitro cultured F3 immortalized human neural stem cell line and in vivo adult Sprague Dawley rats was used to evaluate the cytotoxicity of anticancer drug paclitaxel. In vitro apoptotic activity of paclitaxel was evaluated in F3 cell line by a MTT assay and DAPI test. The cell death was induced with the treatment of 20 nM paclitaxel and chromatin degradation was detected by DAPI staining, which was analyzed by fluorescent microscope. In vivo studies, we also observed nestin immunoreactivity on subventricular zone, which is stem cell rich region in the adult brain of the SD rat. Immunofluorescent staining result shows that pixel intensities of nestin were decreased in a dose dependent manner. These results suggest that paclitaxel is able to induce cytotoxic activity both in F3 neural stem cell line and neural stem cell in SD rat brain.