• The Safety technology
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• no.51
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• pp.12-13
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• 2002

• Journal of the Korea Safety Management & Science
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• v.16 no.1
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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.

• International Journal of Quality Innovation
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• v.10 no.1
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• pp.1-23
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• 2009

Face the process yield rate improvements of motherboard, although general enterprises finish deployment goal of each functions by overall quality managements, through quality improvement methods, industry engineering methods, plan-do-check-act (PDCA) methods and other improvement solutions, but it is only can be improved partially and unable to enhance the yield rate of product to the target. It only can takes one step ahead to enhance the process yield rate of motherboard with six sigma ($6{\sigma}$) overall DMAIC process and tactics. This research aimed to use six sigma quality improvement tactics by DMAIC systematic procedure and tactics, and find the key factors that effect to the process yield rate of surface mount technology. It also identified the keys input and process and output index to satisfy customer requirements and internal process index. The results showed that the major effective factors by fishbone and process failure modes and effects analysis (PFMEA). If the index of input and output that can be quantified, the optimum parameter can be found through design of experiment to ensure that the process is stable. If the factor of input and output that cannot be quantified, we found out the effective countermeasure by Mind_Mapping, make sure whole processes can be controlled stably, to reach the high product quality and enhance the customer satisfaction.

• Journal of Digital Convergence
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• v.10 no.2
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• pp.225-229
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• 2012

A reformer for a small fuel cell system is an apparatus which converts hydrocarbon fuel into hydrogen-rich gas. Among many indices of a reformer, the most crucial index of a reformer is CO concentration in the off-gas out of reformer which must be controled under 5ppm for the efficiency and performance of a system. This paper suggests the criteria of a reformer operation for the stability of a reformer in a fuel cell system by deducing crucial indices and improving processes. The six-sigma technique was applied to verify the optimum control and operation of a reformer of a fuel cell combined heat and power system. The result of temperature control of each parts of a reformer system is the concentration of CO which is the most important factor for the operation of a fuel cell system. The temperature of the parts of a reformer, MTS, LTS and Prox, were controled so that the concentration of CO.

• The Journal of Bigdata
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• v.2 no.1
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• pp.5-15
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• 2017

Six Sigma has been adopted for the last two decades in many industries of manufacturing and service business to implement processs improvement. The methodology has difficulties in discovering target projects in the Define step and in controlling continuous measure and control in the Control step. To address the problem, more advanced system is required to support continuous control and management, and business process management (BPM) can be an effective solution for this problem. In this research, we introduce integrated models of Six Sigma and BPM for the purpose of realizing continuous process improvement, and explain the procedure of analyzing, improving, and monitoring the processes based on the data which has been accumulated in business process execution. It is expected that this integrated approach can maximize business performance by improving and managing business continuously on the integrated platform of two business innovation strategies, Six Sigma and BPM.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.8 no.3
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• pp.673-681
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• 2007

The integration of Quality Circles and Six-Sigma has gained attentions for the attainment of enhanced customer satisfaction, costs reduction, and improved business performance. The purpose of this paper is to verify the benefit from the integration of Quality Circles and Six-Sigma by applying the integrated process for an alcohol manufacturing line. In the integrated process, we used the first three steps of Six-Sigma of Define, Measure, and Analyze(D-M-A) and then applied the concept of Quality Circle, which has good performance in the Improvement and Control(I-C) process. For the selection of the theme of quality circles, Analytic Hierarch Process(AHP) is used, and we also employed the experimental design, which is designed to find an optimal operating condition. Furthermore, the results of the economic analysis confirm that the integration process would be successful in reducing the incidence of defects and the quality cost.

• Journal of the Korea Safety Management & Science
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• v.15 no.1
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• pp.293-301
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• 2013

The purpose of this study is to introduce the limit of previously used six sigma quality process evaluation metrics, $Z_{st}$ and $P_{pk}$, and a solution to overcome this drawback by using a metric based on performance evaluation of Z-factor quality innovation. Case analysis on projects from national six sigma contest from 2011 to 2012 is performed and literature review on new drug development HTS (High Throughput Screening) is used to propose innovative performance evaluation metrics. This research shows that experimental study on six sigma evaluation metric, $Z_{st}$ and $P_{pk}$, have no significance difference between industrial type (Manufacturing, Semi-Public Institute, Public Institute) and CTQ type (Product Technology Type CTQ, Process Technology Type CTQ). Following discovery characterize this quality improvement as fixed target type project. As newly developed moving target type of quality innovation performance metric Z-Factor is used for evaluating experimental study, hypothetical analysis suggests that $Z_{st}$ and $P_{pk}$ share different relationship or even show reciprocal relationship. Constraints of the study are relatively small sample size of only 37 projects from past 2 years and conflict on having interview and communication with six sigma quality practitioner for qualitative experimental study. Both moving target type six sigma innovation project and fixed target type improvement project or quality circle enables efficient ways for a better understanding and quality practitioner use by applying quality innovation performance metric. Downside of fixed target type quality performance evaluation metric, $Z_{st}$ and $P_{pk}$, is presented through experimental study. In contrast, advantage of this study is that high throughput requiring product technology, process technology and quantum leap typed innovation effect is evaluated based on precision and accuracy and Z-Factor that enables relative comparison between enterprises is proposed and implemented.

• Journal of Korea Society of Industrial Information Systems
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• v.25 no.4
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• pp.49-63
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• 2020

Municipal governments today are facing increasingly complex issues while resources continue to be constraint but the service quality expectation from citizen is more demanding. They must develop and implement tools that help manage operations more efficiently. While Lean Six Sigma principle and tools have been widely applied to profit organizations, the extant literature has not provided many cases of such application to local governments. This research presents a case study of applying Lean Six Sigma approaches and tools to a municipal government of a small town in USA to improve process efficiency, quality performance, and citizen satisfaction. In this case study, DMAIC (Define, Measure, Analyze, Implement, and Control) is used as a tool to define current issues, develop, and measure performance metrics, and recommend action plans. The result of this case study shows that applying the principles and tools of Lean Six Sigma provides an excellent way to improve the process efficiency and quality of providing public work services at a local government.

• Journal of Korean Institute of Industrial Engineers
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• v.32 no.4
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• pp.323-337
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• 2006

Samsung, recognized as a global leading company, has huge and complex supply chain structures and has been improving them continuously for its fast-growing global businesses. SCM 6 Sigma is the state-of-the-art methodology developed through a combination of SCM innovation concepts accumulated from SCM Business Group in Samsung SDS and 6 Sigma which has successfully settled down as the management innovation tool for many companies in Samsung. The ultimate goal of SCM 6 Sigma is to train and develop future supply chain leaders who are more capable of leading SCM innovations. By leveraging the established 6 Sigma Belt System, Samsung aims to alleviate a shortage of SCM talents that has been a bottleneck in improving SCM performances at its group companies. This explains why SCM 6 Sigma is created. SCM 6 Sigma is the unique and critical component for Samsung to implement its various strategies for continuous improvement of its operations at a higher level of effectiveness and systematically as well. In return on these efforts, many SCM innovation projects have been successfully executed through SCM 6 Sigma up to today. In this paper, we introduce the methodology and explain the business rationale behind it together with its deployment case.

• International Journal of Quality Innovation
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• v.8 no.3
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• pp.23-34
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• 2007

Many practitioners strive to increase the efficiency of their product development. In addition, smaller companies must satisfy customers' expectations of their product development. These expectations can be e.g. use of specific methodologies such as Lean Product Development (LPD) and/or Design for Six Sigma (DFSS). This study attempts to identify differences and similarities between these methodologies and the connection between them. This comparison is of interest to practitioners that must choose a strategy for their product development as well as to researchers. The aim of both methodologies is to reduce waste and time of development and to raise the quality of a product at the very roots of the product: its development. LPD and DFSS help development managers to structure projects and focus as much as possible on customer expectations and satisfaction.