• Journal of the Korean Statistical Society
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• 제22권1호
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• pp.39-54
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• 1993

In the three-factor nested variance component model with equal numbers in the cells given by $y_{ijkm} = \mu + A_i + B_{ij} + C_{ijk} + \varepsilon_{ijkm}$, the exact confidence intervals of the variance component of $\sigma^2_A, \sigma^2_B, \sigma^2_C, \sigma^2_{\varepsilon}, \sigma^2_A/\sigma^2_{\varepsilon}, \sigma^2_B/\sigma^2_{\varepsilon}, \sigma^2_C/\sigma^2_{\varepsilon}, \sigma^2_A/\sigma^2_C, \sigma^2_B/\sigma^2_C$ and $\sigma^2_A/\sigma^2_B$ are not found out yet. In this paper approximate lower and upper confidence intervals are presented.

• 한국지반공학회논문집
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• 제26권12호
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• pp.71-79
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• 2010

설계지반정수의 합리적인 결정과 확률론적 방법에 의한 지반구조물의 설계를 위해서는 지반정수의 변동계수에 대한 신뢰성 있는 추정이 필요하다. 본 논문에서는 인천 송도지역의 지반조사자료를 이용하여 Three-Sigma Rule 및 통계적인 방법과 같은 표준편차 추정방법의 적용성을 평가해 보았다. 무작위성을 보이는 지반 물성값 중, 변동성이 작은 ${\gamma}_t$, ${\gamma}_b$, $e_0$는 $N_o=6$을, 상대적으로 변동성이 큰 $C_{\alpha}/C_c$, $C_c(1+e_0)$, $c_v$, $k_v$의 경우 $N_{\sigma}$=4.2~5.3을 사용하여 Three-Sigma Rule을 적용하면 통계학적 방법과 유사한 결과를 얻는 것이 관찰되었다. 또한 깊이에 따라 경향성을 보이는 비배수전 단강도는 약 40%의 변동계수를 보이는 것으로 관찰되었으며 $N_{\sigma}$=4를 사용하면 Three-Sigma Rule로 얻는 것으로 나타났다. 본 논문에서 추정한 변동계수를 이용하여 지반정수의 신뢰구간, 특성값을 결정할 수 있었다.

• 대한안전경영과학회지
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• 제8권4호
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• pp.239-247
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• 2006

This paper is to propose new features and models for process innovation after classifying in three categories ; conventional six sigma, lean six sigma and 3rd generation six sigma. First considering two project types which are bottom-up and tod-down, DMAIC process is linked up with QC story 15 steps. Secondly, I present Koreanized lean six sigma model using Japanese production technology and principles. Lastly, this paper also depicts a new 3rd generation six sigma model utilizing MBNQA management quality system.

• Journal of Advanced Marine Engineering and Technology
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• 제7권2호
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• pp.29-35
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• 1983

In general, for measuring residual stresses in plane stress state, two principal stresses {\sigma}_1 , {\sigma}_2$ and their directions .theta., should be determined. Naturally, for deciding three unknowns ${\sigma}_1, {\sigma}_2, ${\theta}$-three informations are necessary and therefore three strain gages are required for determining residual stresses at one point. In this paper, we tried to measure the residual stresses of one point with only two strain gages by drilling twice the hole of different diameters at the point and by detecting relaxation strains for each hole-drilling. We present also the formulas for determining the residual stresses from relaxation strains detected by strain gages in each hole-drilling. We carried out experiment, determining principal stresses and their directions of specimens applied specified uniform stress, and compared experimental results with the values calculated by formulas presented in this paper. The values calculated by formulas presented in this paper are always a little greater than the experimental results.

• 품질경영학회지
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• 제29권3호
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• pp.166-176
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• 2001

This paper considers a six sigma project for reducing the color variation of the monitor materials in a chemical plant. The project follows a disciplined process of five macro phases: define, measure, analyze, improve, and control (DMAIC). A process map is used to identify process input variables. Three key process input variables are selected by using an input variable evaluation table; a melting pressure, a coloring agent, and a DP color variation. DOE is utilized for finding the optimal process conditions of the three key process input variables. The sigma level of defects rate becomes a 4.58 from a 2.0 at the beginning of the project.

• 품질경영학회지
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• 제34권1호
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• pp.1-12
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• 2006

This paper presents a six sigma project for improving gate painting quality in a medium-sized automotive part company. The project follows a disciplined process of five macro phases: Define, Measure, Analyze, Improve, and Control. A CTQ(critical to quality) is determined based on COPQ(cost of poor quality) analysis, and a process map is utilized for identifying process input variables. Three KPIV s(key process input variable) are selected; Painting Temperature, Painting Quantity, and Painting Viscosity, and DOE(design of experiments) is utilized for finding the optimal process conditions for three KPIVs. MINITAB software is used for data analyses and DOE. The sigma level of defects rate has improved from 2.93 to 3.66.

• 산업경영시스템학회지
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• 제27권1호
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• pp.9-14
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• 2004

More than three years have passed since Korean companies introduced Six-Sigma. Each company used a lot of quality improvement tools for years. However, the tools have been taught to the companies with a little understanding of Six sigma tools. Therefore, it is difficult to use the tools correctly at appropriate time. This survey paper was conducted on MBBs and BBs of the manufacturing companies that introduced Six-Sigma. It is intended, in this paper, to provide the companies that will be introduce Six-Sigma a guideline of training course and tools by understanding the importance of each DMAIC stage of Six-Sigma, examining the frequently used tools in each process and their performances, and selecting the key tools for each stage based on the result of this survey.

• 대한간호학회지
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• 제31권5호
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• pp.808-817
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• 2001

To survey the present status of the gerontological nursing course at three year diploma programs, baccalaureate degree programs(BSN), and graduate programs in Korea, and to analyze the contents of the syllabus and gerontological nursing textbooks to provide the basic data in developing a standard model for gerontological nursing curriculum. Method: Data was collected from all the nursing programs in Korea from Nov. 2000 to Feb. 2001 by mail and fax. Result: The gerontological nursing courses has been offered 36 diploma program, 40 BSN, and 17 graduate programs. And the credits of the gerontological nursing course offered by the program were as follows : one credit (10 diploma and 8 BSN), two credits (22 diploma and 29 BSN), and three credits (1 BSN). The contents of curri- culum were analyzed by comparing the core curriculum of NGNA. The majority of the schools included Gerontological Nursing in General, Theory of Aging, Aging Processes, Care Plan Options, and Common Health Problems. The subjects which very few school cover are Legal/ Ethical Issues, Evaluation, Regulatory & Reimbursement Issues, Education Issues, Nursing Research in Gerontology, and Environmental Issues of Older Adults. There were some differences in these results among diploma courses, BSNs, and graduate schools. The gerontological nursing textbooks contained similar contents to those of the diploma and the baccalaureate programs.

• 대한안전경영과학회지
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• 제11권1호
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• pp.121-130
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• 2009

This paper considers a six sigma project for reducing the cost copper of the cable materials in a electric wire company. The project follows a disciplined process of five macro phases: define, measure, analyze, improve, and control (DMAIC). A process map is used to identify process input variables. Three key process input variables are selected by using an input variables are selected by using an input variable evaluation table: large cable, plating, and a twisted pair. DOE is utilized for finding the optimal process conditions of the three key process input variables. The implementing result of this six sigma project is enable for reducing of the 2.8% copper materials.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 1999년도 가을 학술발표회 논문집
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• pp.95-102
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• 1999

It is important to estimate the magnitude of settlement and the time of primary consolidation in geotechnical engineering projects. For these purposes, site explorations and laboratory tests are usually performed. However, the mechanical properties determined from laboratory tests on the samples obtained by different sampling techniques show different trends. In this study, three types of consolidation test were carried out on the soil samples obtained by three different sampling techniques (76mm tube, 76mm piston, and block samples), to verify the effect of sample disturbance on consolidation properties. It was found that sampling methods have influence on the $\varepsilon$ - log $\sigma$'$_{v}$ relationship. While insignificant difference of compression indices from the samples obtained by different sampling techniques was observed in compression region, these values showed a different trend in precompression region. The values of $c_{v}$ and k of block samples had a tendency to be larger than those of piston and tube samples. At consolidation pressure larger than $\sigma$'$_{p}$, however, these properties became similar regardless of sampling methods. The block and piston samples gave slightly higher values of $C_{a/}$ $C_{c}$ than tube samples. In the results of I $L_{EOP}$ and CRS test, it was observed that the values of $\sigma$'$_{p measured}$/$\sigma$'$_{p best estimated}$ of Yang-San clay decreases when strain becomes larger than 1.0% and that precompression strain of block samples is in the range of 1.5~2.0% while those of piston and tube samples are 1.75~3.75%. It was also shown that the values of $\sigma$'$_{p}$ of block samples exceed those of piston and tube samples by about 6~10%.6~10%.%.%.%.%.