• 대한안전경영과학회지
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• 제16권1호
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• pp.169-176
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• 2014

This research discusses the characteristics and the implementation strategies for two types of quality metrics to analyze innovation effects in six sigma projects: fixed specification type and moving specification type. $Z_{st}$, $P_{pk}$ are quality metrics of fixed specification type that are influenced by predetermined specification. In contrast, the quality metrics of moving specification type such as Strictly Standardized Mean Difference(SSMD), Z-Score, F-Statistic and t-Statistic are independent from predetermined specification. $Z_{st}$ sigma level obtains defective rates of Parts Per Million(PPM) and Defects Per Million Opportunities(DPMO). However, the defective rates between different industrial sectors are incomparable due to their own technological inherence. In order to explore relative method to compare defective rates between different industrial sectors, the ratio of specification and natural tolerance called, $P_{pk}$, is used. The drawback of this $P_{pk}$ metric is that it is highly dependent on the specification. The metrics of F-Statistic and t-Statistic identify innovation effect by comparing before-and-after of accuracy and precision. These statistics are not affected by specification, but affected by type of statistical distribution models and sample size. Hence, statistical significance determined by above two statistics cannot give a same conclusion as practical significance. In conclusion, SSMD and Z-Score are the best quality metrics that are uninfluenced by fixed specification, theoretical distribution model and arbitrary sample size. Those metrics also identify the innovation effects for before-and-after of accuracy and precision. It is beneficial to use SSMD and Z-Score methods along with popular methods of $Z_{st}$ sigma level and $P_{pk}$ that are commonly employed in six sigma projects. The case studies from national six sigma contest from 2011 to 2012 are proposed and analyzed to provide the guidelines for the usage of quality metrics for quality practitioners.

• 품질경영학회지
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• 제27권1호
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• pp.223-231
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• 1999

The concept of six sigma was introduced at and popularized by Motorola in its quest to reduce defects of manufactured electronics products. When used as a metric, six sigma technically means having no more than 3.4 defects per million opportunities in any process, product, or service. More important than the technical definition is the concept of six sigma as a disciplined, quantitative approach for improvement of defined metrics in manufacturing, service, or financial processes. This approach derives the overall process of selecting the right projects based on their potential to improve performance metrics and selecting and training the right people to get the business results.

• 대한임상검사과학회지
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• 제36권2호
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• pp.121-126
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• 2004

The primary goal of six sigma is to improve patient satisfaction, and thereby profitability, by reducing and eliminating defects. Defects may be related to any aspect of customer satisfaction: high product quality, schedule adherence, cost minimization, process capability indices, defects per unit, and yield. Many six sigma metrics can be mathematically related to the others. Literally, six means six standard deviations from the mean or median value. As applied to quality metrics, the term indicates that failures are at least six standard deviations from the mean or norm. This would mean about 3.4 failures per million opportunities for failure. The objective of six sigma quality is to reduce process output variation so that on a long term basis, which is the customer's aggregate experience with our process over time, this will result in no more than 3.4 defect Parts Per Million(PPM) opportunities (or 3.4 Defects Per Million Opportunities. For a process with only one specification limit (upper or lower), this results in six process standard deviations between the mean of the process and the customer's specification limit (hence, 6 Sigma). The results of applicative six sigma experiment studied on 18 items TP, ALB, T.B, ALP, AST, ALT, CL, CK, LD, K, Na, CRE, BUN, T.C, GLU, AML, CA tests in clinical chemistry were follows. Assessment of process performance fits within six sigma tolerance limits were TP, ALB, T.B, ALP, AST, ALT, CL, CK, LD, K, Na, CRE, BUN, T.C, GLU, AML, CA with 72.2%, items that fit within five sigma limits were total bilirubin, chloride and sodium were 3 sigma. We were sure that the goal of six sigma would reduce test variation in the process.

• 한국산업경영시스템학회:학술대회논문집
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• 한국산업경영시스템학회 2002년도 춘계학술대회
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• pp.397-402
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• 2002

Six Sigma is one of the most active subjects in quality management. This study deals with some existing weaknesses that may arise in implementing Six Sigma in real world situations. The main weaknesses discussed here include the lack of understanding of cultural aspects on the nations and industries, the poor linkage between quality, finance and accounting from the bottom line point of view, and the difficult development process of metrics for all improvement results to validate the effect of Six Sigma. Finally, the key success characteristics for a good Six Sigma project are presented.

• 산업경영시스템학회지
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• 제25권1호
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• pp.29-34
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• 2002

Six Sigma is one of the most active subjects in quality management. This studs deals with some existing weaknesses that may wise in implementing Six Sigma in real world situations. The main weaknesses discussed here include the lack of understanding of cultural aspects on the nations and industries, the poor linkage between quality, finance and accounting from the bottom line point of view, and the difficult development process of metrics for all improvement results to validate the effect of Six Sigma. Finally, the key success characteristics for a good Six Sigma project are presented.

• 대한임상검사과학회지
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• 제52권2호
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• pp.91-97
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• 2020

비타민 D 검사의 표준화는 전 세계적으로 계속되고 있으며, 결과의 정확성을 향상시키기 위해 많은 노력을 기울였다. 본 연구의 목적은 외부 품질 평가(EQA) 프로그램을 이용하여 비타민 D 검사의 시그마 메트릭스 값을 분석하는 것이다. 시그마 메트릭스는 검사기관에서 수행한 정량적 시험에 사용되며, 분석결과는 품질 측면에서 객관적으로 시각화할 수 있다. 이 분석은 약 300개의 검사기관이 참여한 가운데, CAP의 외부정도관리 프로그램인 2019년 정확도 기반 비타민 D (ABVD) 조사 결과를 이용하여 수행하였다. CDC 표준검사기관에서 얻어진 표준 값 6개의 서로 다른 농도에서는 시그마 메트릭 값이 각각 1.00, 1.85, 2.42, 1.01, 1.54 및 0.78로 분석되었다. 평균 1.43 시그마 메트릭 값을 보여주었다. 특히, 검체 ABVD-16, 17의 결과값에서의 양성 편향은 비타민 D 측정을 위한 표준검사법인 액체크로마토그래피 탠덤 질량 분석(LC-MS/MS)에 대해서만 나타났다. 차이의 원인은 다양한 비타민 D 대사산물에 대한 다양한 교차 반응으로 설명된다. 검사 기관은 전반적인 성능을 개선해야 한다.

• 한국경영과학회:학술대회논문집
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• 한국경영과학회/대한산업공학회 2005년도 춘계공동학술대회 발표논문
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• pp.579-584
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• 2005

A metric is a measure of one factor of a company's performance. The metrics are used to monitor the overall performance of the company for achieving business objectives. Insufficient metrics cannot reflect company's conditions. Therefore, it is important to be equipped with 'good' metrics. This study introduces the concept of metric quality and proposes its dimensions. The study also presents application scenarios that show the role and usefulness of the metric quality.

• 산업경영시스템학회지
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• 제27권1호
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• pp.103-108
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• 2004

Companies adopted a program called Six Sigma, in order to make fundamental changes in the way the company operated to fulfill customers' expectations. Six Sigma reduces the occurrence of defects. This approach derives the overall process of selection the right projects based on their potential to improve performance metrics and selection and training the right people to get the business results. However, in the course of Six Sigma process steps, companies are in the face of problems. This study is to solve the problems using TOC(Theory of Constrains). TOC is methodology for solving key problem in system which is called Constraints. Nowadays, its application is going to be wide and its concept is being implemented. In this paper, it is showed possibility of application TOC to Six Sigma.

• 품질경영학회지
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• 제27권4호
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• pp.266-279
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• 1999

Today, Companies are facing the harsh realities of a competitive environment. This is no time for revolutionary change. Instead, Companies are instituting revolutionary change meant to have impact within a very short time frame. Bold steps are required to lead the industry into a future of improved efficiency and significant productivity gains. GE, as well as Intel, Motorola, and other companies adopted a program called Six Sigma, in order to make fundamental changes in the way the company operated to fulfill customers'expectations. Six sigma reduces the occurrence of defects from a 3 sigma level of 66,800 defects per million to a 6 sigma level-less than 4defects per million. The goals and metrics of the company's Six Sigma process clearly have had a positive effect on customer satisfaction and customer perception of the company.

• 대한안전경영과학회:학술대회논문집
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• 대한안전경영과학회 2004년도 추계학술대회
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• pp.81-85
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• 2004

Companies adopted a program called Six Sigma, in order to make fundamental changes in the way the company operated to fulfill customers' expectations. Six Sigma reduces the occurrence of defects. This approach derives the overall process of selection the right projects based on their potential to improve performance metrics and selection and training the right people to get the business results. However, in the course of Six Sigma process steps, companies are in the face of problems. This study is to solve the problems using TP(Thinking Process) of TOC(Theory of Constraints). TOC is methodology for solving key problem in system which is called Constraints. Nowadays, its application is going to be wide and its concept is being implemented. In this paper, it is showed possibility of application TOC to Six Sigma.