• The Transactions of The Korean Institute of Electrical Engineers
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• v.58 no.2
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• pp.217-224
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• 2009

This paper presents a new AC/DC converter scheme for HVDC system to achieve a high power factor operation. The new AC/DC converter consists of two 12-pulse bridge converters in series: the primary and auxiliary converters. Ignition angles of the main and auxiliary converters are controlled independently to maintain the nominal DC voltage and control auxiliary voltage. The resulted DC voltage obtained by superimposing the above two phase modulated voltages can be controlled very rapidly over a wide range, and a high power factor operation is achieved. Performance improvements in power factor and harmonic distortion are validated by theoretic derivations and experiments with prototype HVDC system. With the proposed converters, investment for reactive power compensation and filter in HVDC system can be saved significantly.

• Communications for Statistical Applications and Methods
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• v.6 no.3
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• pp.707-718
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• 1999

Non-regular designs such as the Plackett-Burman(PB) design have traditionally been used for screening only main effects because of complex aliasing. But it was found that these designs could be used to estimate the 2-factor interactions as well as main effects through the hidden projection property. The goal of this paper is to propose the estimable model when projecting the 12-run PB design using the algebraic geometric method. The core of this method considers the design as a affine variety and the Grbner basis of the design ideal for this affine variety gives the estimable polynomial models. As the results of applying the 12-run PB design it is actually found that this design has the models not only with 2-factor interactions but with 3-factor. This design is the maximal fan in 4-factor projection.

• Journal of the Korean Home Economics Association
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• v.30 no.2
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• pp.97-111
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• 1992

In this survey, we tried to find out number of participating and main purpose of that "Kye" meeting of all family members in rural community. Main purpose is follows; First, Differences by rural area, number of participating and main purpose of that "Kye" meeting of all family members in rural community. Second, Relationship between residence years by the head of a family and numbers in rural community. Third, Relationship between size of owned land(paddy field and uplaned) by the head of a family and number of participating and main purpose of that "Kye" meeting of all family members in rural community. Fourth, Relationship between size of cultivated land(paddy field and uplaned) by the head of a family and number of participating and main purpose of that "Kye" meeting of all family memebers in rural community. The main results are as follows; First, there are different points by the kind of rural area in number of participating and "Kye for friendly gathering", "Kye for saving", "Kye for sightseeing". Second, variable of residence years of the head of a family is only negative influential factor in "Kye for saving". Third, variable of size of owned land is positive influential factor in total number of participating "Kye", "Kye for friendly gathering", "Kye for saving" and "Kye for sightseeing". Fourth, variable of size fo cultivated land is positive influential factor in total number of participating "Kye", "Kye for mournig and marriage", "Kye for friendly gatiering", "Kye for saving" and "Kye for sightseeing". It seems that "Kye" meetings are still a preferred means by the jrural community to gather the cooperation among rural population. But the purpose of "Kye" meetings has changed from the family centered such as worship or marriage and mouring of family members to out of the family centered events such as friendly gathering, sightseeing.

• Korean Journal of Occupational Health Nursing
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• v.13 no.2
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• pp.89-103
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• 2004

One of the major health problems of working women is job stress according to many studies. However, existing job stress questionnaires are suitable for men and men's job environments only, and do not reflect emotional labor for sales people. The aim of this research is to find women's job stress factors. The subjects of this investigation are married working women in sales since they experience emotional labor in addition to physical and psychological labor and the work-family conflict is very important job stressor for them. The job stressor of married sales women was analyzed through qualitative research. After I had in-depth interviews with 20 married sales women, I identified 49 new concepts, 3 main categories and 17 sub categories. The results are like the following. 1. 3 main categories are job factor, aggravate factor, and compensate factor. 2. Job factor has 5 sub-categories including 'increasing of selling', 'emotional labor' and 'physical burden'. 3. Aggrabate factor has 6 sub-categories including 'work/family conflict', 'relationship with higher office' and 'relationship with a fellow worker' 4. Compensate factor has 6 sub-categories including 'opportunity of employment', 'discrimination', and 'prestige' Consequently this study newly found some major job stressors for married working women in sales department.

• Journal of the Korean Society of Costume
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• v.63 no.1
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• pp.97-107
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• 2013

To give satisfaction with the fit to a wearer, the wearer's body size and body types should be considered first, this study conducted the descriptive statistical analysis on the upper body measurements of women in their 20s because their body shape has reached the completion stage of adult female's physical development. Also, the analysis classified their upper body types into groups to secure basic data for (maximum satisfaction with the fit of ready-to-wear clothing. The factor analysis was conducted using 49 items of measurement. The main factor analysis was used as a factor extraction method. After extracting the factors with Eigenevalues over 1, the factor loadings were drawn using the Varimax rotation. As a result, 6 factors were extracted. To secure internal consistency, factors that could lower the reliability of the experiment were taken out, so only 36 of the 49 items were used for the analysis. After selecting the items to recognize the main features of each body type, they were used for the final factor analysis. The entire R square of the 6 factors was 84.06%. To classify the upper body types of women in their 20s and to recognize the main features of each body shape type, the researcher conducted the cluster analysis with the items generated from the factor analysis. Through the cluster analysis, the upper body type of women in their 20s were classified into 3 body types. Also, since there are some restrictions on this research objects in terms of local and numbers of measured objects, the results of the this research should only be used as basic data.

• International Journal of Computer Science & Network Security
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• v.22 no.4
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• pp.299-309
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• 2022

Human factor represents a very challenging issue to organizations. Human factor is responsible for many cybersecurity incidents by noncompliance with the organization security policies. In this paper we conduct a comprehensive review of the literature to identify strategies to address human factor. Security awareness, training and education program is the main strategy to address human factor. Scholars have consistently argued that importance of security awareness to prevent incidents from human behavior.

• Journal of the Earthquake Engineering Society of Korea
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• v.18 no.6
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• pp.301-308
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• 2014

A suspension bridge is a type of bridge in which the beam is suspended by load-bearing cables. There are two classifications: the self-anchored suspension bridge has the main cable anchored to the bridge girders, and the earth-anchored suspension bridge has the main cable anchored to a large anchorage. Although a suspension bridge is structurally safe, it is prone to be damaged by various actions such as hurricanes, tsunamis and terrorist incidents because its cables are exposed. If damage to a cable eventually leads to the cable rupture, the bridge may collapse. To avoid these accidents, studies on the dynamic behavior of cable bridges due to the cable rupture have been carried out. Design codes specify that the calculated DAF (dynamic amplification factor) should not exceed a certain value. However, it has been difficult to determine DAFs effectively from dynamic analysis, and thus no systematic approach has been suggested. The current study provides a guideline to determine DAFs reliably from the dynamic analysis results and summarizes the results by applying the method to an earth-anchored suspension bridge. In the study, DAFs were calculated at the location of four structural parts, girders, pylons, main cable and hangers, with variations in the rupture time.

• Research in Community and Public Health Nursing
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• v.19 no.2
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• pp.247-259
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• 2008

Purpose: This study was conducted to develop a teacher-efficacy scale which is adequate for heath education teachers. Method: A preliminary questionnaire was made based on the hypothetical factors. A total of 364 health education teachers answered to the preliminary test, and the potential factors of teacher-efficacy were checked out by exploratory factor analysis (EFA). In the main test 378 health education teachers answered, the factor structure was drawn by EFA, and confirmatory factor analysis (CFA) was conducted to test and the fitness of the factor model. Results: Through the preliminary test, 5 potential factors were found, which were instruction, health-service, administrative task, interpersonal relationship, and community connection. Also, 48 items were reduced to 31 items. Through the main test, from the 34 items were extracted 4 factors with 24 items, And then teacher-efficacy scale was developed, which included the subscales of instruction efficacy, health-service efficacy, task-interpersonal efficacy, and community connection efficacy. Conclusion: Different from that for other subject teachers, the factor structure for health teachers had 4 factors with 24 items. The scale developed in this study is consistent with health teachers' work areas, and for this reason, has significance as a adequate and valid scale to measure teacher-efficacy of health education teachers.

• Journal of Korea Port Economic Association
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• v.35 no.3
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• pp.41-60
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• 2019

This study aims to identify factors that pharmaceutical logistics companies must consider when selecting a logistics center; it also aims to analyze the importance-satisfaction-of these factors by using IPA. The main results are as follows. First, overall, the aforementioned factors are divided into logistics factor, economic factor, environmental factor, and policy factor, and most of the specific attributes of each main factor are less satisfied than the importance. Second, the users of pharmaceutical logistics are divided into producers, distributors, clinics, and pharmacies. The analysis of each user shows a need to improve logistics factors as well as an overinvestment in environmental factors. The results can provide drug distribution companies directions for selecting logistics centers as well as strategic implications.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 1998.10a
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• pp.183-190
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• 1998

In this study, I-type girders, main members of a steel composite bridge, are designed by Load and Resistance Factor Design method as well as Allowable Stress Design method. The width, height web thickness and flange thickness of main girders are set as design variables. The design program connects optimization program ADS, which is coded with FORTRAN, and a main program coded with $C^{++}$. In this study, it is shown that in this particular steel composite bridge, the design by The Load and Resistance Factor Design method is more economical than that by The Allowable Stress Design method.d.