• Journal of the Korea Safety Management & Science
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• v.8 no.6
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• pp.109-118
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• 2006

This paper proposes service layout strategy considering service characteristics by the use of benchmarking production system such as layout by P-Q chart, improvement tool, automated system, Toyota production system and lean production system. This paper represents operation methodology of statistical process control using control chart for service performance outcomes.

• Journal of the Korea Management Engineers Society
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• v.23 no.4
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• pp.73-86
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• 2018

Most electric products produced during the manufacturing process are produced after design and mass production under a given control standard. In particular, the development phase should present the criteria for the production process by setting appropriate limits based on the performance being targeted. Even if the standard of performance is set considering the performance of the process, measuring the performance of the product after actual production results will cause nonconformities with the expected results. Among the performance of electrical products, Energy standards represented by energy consumption efficiency continue to be of importance, and are mandatory standards that correspond to national standards in most countries. Therefore, statistical quality control of these standards shall basically have a large number of test equipment for each product, ensure sufficient test time and continuous sampling of product samples. In the end, companies that produce and sell electric appliances are striving to control mass production at a great cost, but this is not acceptable. This study presents basic characteristics of the energy efficiency of electrical products and proposes and conducts a case study on statistical production control methods for performance variation across products under the standards about domestic and international regulations.

• Journal of Korea Society of Industrial Information Systems
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• v.15 no.1
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• pp.47-57
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• 2010

There have been many problems to apply SPC(Statistical Process Control) which is a traditional process control technology to the process of multi-product, small-sized production because a machine in the process manufactures small numbers, but various kinds of products. Therefore, we need the new process control system that can flexibly control the process by setting up the SPEC rules and the KNOWHOW rules. The SPEC rule contains the combination of diverse conditions to specify the characteristics of various products. The KNOWHOW rule is based on engineers' know-how. The study suggests the Rule-base Process Control that can be optimized to the multi-product, small-sized production. It was validated in the process of semiconductor production.

• Journal of Haehwa Medicine
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• v.25 no.1
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• pp.71-86
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• 2016

Objective : Hongyi (Formica yessensis) is the dried insect of fomicidae. In previous studies, it appeared possibilities on anti-thrombosis, preventing atherosclerosis, treating rheumatoid disease, and inhibiting hela cell. In this study, we investigated anti-inflammatory effects and mechanism of Hongyi. Methods : Hongyi A was extracted by water and made dried powder. Hongyi B was extracted by ethanol and made dried powder. We measured Nitric Oxide (NO) production on the mouse macrophages (RAW 264.7), mouse vascular endothelial cell (MOVAS) and human vascular endothelial cell (HUVEC) for anti-inflammatory effect. In addition, we conducted reverse transcription reaction (RT-PCR) for investigating the mechanism. Results : In RAW 264.7 macrophages stimulated by LPS, Hongyi A ($100{\mu}g/m{\ell}$) decreased NO production compared with LPS $2{\mu}g/ml$ control group with statistical significance (p<0.05). Hongyi A (50, $100{\mu}g/m{\ell}$) also decreased NO production compared with LPS $4{\mu}g/ml$ control group with statistical significance (p<0.01). Hongyi B (50, $100{\mu}g/m{\ell}$) decreased NO production compared with LPS $2{\mu}g/ml$ control group with statistical significance (p<0.01). Hongyi B (10, 50, $100{\mu}g/m{\ell}$) also decreased NO production compared with LPS $4{\mu}g/ml$ control group with statistical significance (p<0.01, p<0.001, p<0.001). In the MOVAS, Hongyi A and B increased NO production compared with control group. In the HUVEC, Hongyi B increased NO production compared with control group. The expression of NF-${\kappa}B$ in 12-hours MOVAS culture was decreased by Hongyi A and B (10, $50{\mu}g/ml$) compared with control group, but expression of $I{\kappa}B$ was increased. In the 24-hours MOVAS culture, expression of $I{\kappa}B$ was significantly increased. The expression of NF-${\kappa}B$ in 12-hours HUVEC culture was decreased by Hongyi A and B compared with control group, but expression of $I{\kappa}B$ was increased. Hongyi B also increased eNOS mRNA gene expression. Conclusions : Hongyi A and B showed anti-inflammatory effect in mouse macrophages with the activation of vascular endothelial cell through NO production in MOVAS and HUVEC repectively. Honyi B showed superior effect than Hongyi A, but additonal mechanism study should be conducted.

• Korean Management Science Review
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• v.31 no.3
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• pp.27-39
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• 2014

We derive a generalized statistic form of Q control chart, which is especially suitable for short run productions and start-up processes, for the detection of process mean shifts. The generalization means that the derived control chart statistic concurrently uses within lot variability and between lot variability to explain the process variability. The latter variability source is noticeably prevalent in lot type production processes including semiconductor wafer fabrications. We first obtain the generalized Q control chart statistic when both the process mean and process variance are unknown, which represents the case of implementing statistical process control charting for short run productions and start-up processes. Also, we provide the corresponding generalized Q control chart statistics for the rest of three cases of previous Q control chart statistics : (1) both the process mean and process variance are known (2) only the process mean is unknown and (3) only the process variance is unknown.

• Journal of Korean Society for Quality Management
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• v.5 no.2
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• pp.3-20
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• 1977

The purpose of this Study is to develope the Role of Statistics in Industrial mass production. The process of mass production will be divided into three steps, that is, Standardization, production and inspection. The Statistics is applied to Specificat-ions, Quality Control and Sampling inspection in these three steps. The applications have developed to Statistical methods based on probability theory. And then, The improved plan is exhibited the point of problems of introducting of spreading of quality control throughout field survey.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.29 no.2
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• pp.97-103
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• 2006

Recently, the control chart is developed for monitoring processes with normal short production runs by the coefficient of variation(CV) characteristic for a normal distribution. This control chart does not work well in non-normal short production runs. And most of industrial processes are known to follow the non-normal distribution. Therefore, the control chart is required to be developed for monitoring the processes with non-normal short production runs by the CV characteristics for a non-normal distribution. In this paper, we suggest the control chart for monitoring the processes with a gamma short runs by the CV characteristics for a gamma distribution. This control chart is denoted by the gamma CV control chart. Futhermore evaluated the performance of the gamma CV control chart by average run length(ARL).

• Journal of Korean Society of Industrial and Systems Engineering
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• v.27 no.3
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• pp.14-20
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• 2004

The coefficient of variation(CV) which is a relatively dimensionless measure of variability is widely used to describe the variation of sample data. However, the properties of CV distribution are little available and few research has been done on estimation and interpretation of CV. In this paper, we give an outline of statistical properties of coefficient of variation and design of control chart based on this statistic. Construction procedures of control chart are presented. The proposed control chart is an efficient method to monitor a process variation for short production run situation. Futhermore, we evaluated the performance of CV control chart by average run length(ARL).

• Journal of Korean Society for Quality Management
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• v.41 no.3
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• pp.487-494
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• 2013

Purpose: In this study, we propose the precision guided munitions verification methodology using the statistical analysis method has been proposed. and it can be applied to the precision guided munitions quality assurance work. Methods: This modeling is based on Failure Mode and Effects Analysis, Statistical Process Control, Defense Quality Managerment System, Production Readiness Review, Manufacturing Readiness Assesment and so on. Results: The Process Control Modeling that has the following procedures ; searching the critical to quality, statistical analysis by process, verify process. Moreover, the effectiveness of the methodology is verified by applying to the precision guided munitions. Conclusion: To achieve a analysis methods of statistical process control and verify process for precision guided munitions.

• Communications for Statistical Applications and Methods
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• v.12 no.2
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• pp.265-273
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• 2005

In this paper, we proposed multivariate EWMA control charts for both combine-accumulate and accumulate-combine approaches to monitor dispersion matrix of multiple quality variables. Numerical performance of the proposed charts are evaluated in terms of average run length(ARL). The performances show that small smoothing constants with accumulate-combine approach is preferred for detecting small shifts of the production process.