• 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.33 no.4
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• pp.96-102
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• 2005

Cusum control chart is an efficient method to detect the change of process status. Many variants of cusum have considered, and the effects of design parameters have reviewed. To find the best cusum out of variants and to decide the best values of the design parameters, we need a criterion measuring the performance of the cusum control chart. People used and suggested several criterions which appear to be similar, but those have quite different properties. In this paper we review the properties of performance measure of cusum and its variants. Our goal is to provide fair and impartial criterion for comparison of cusums when the decision boundaries of the cusums are much different each other. We comparatively tested newly suggested measure and traditional measure with the examples of cumulative scored chart as a special case of cusum chart.

• Publications of The Korean Astronomical Society
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• v.28 no.3
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• pp.37-54
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• 2013

China and Korea have a long history of star charts, dating from the prehistoric period. Historically, Korean astronomy has been deeply influenced by China over the last two thousand years, particularly on constellation system. Therefore, Chinese and Korean traditional star charts have many similarities in terms of shape of constellation, number of star, and so forth. Korean star charts, however, have lots of unique characteristics distinguishing from Chinese ones, such as, size of star and position of constellation. Overall knowledge of the Chinese star chart is required to study the Korean star chart. In this paper, I focus on introducing selected star charts in China and Korea. Although this review is very limited, I hope that this paper is helpful in research in the field of historical astronomy.

• Journal of Korean Society for Quality Management
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• v.40 no.2
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• pp.176-185
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• 2012

After a work of Derman and Ross(1997) that considered simple main runs rules and derived ARL (Average Run Length) using Markov chain modeling, $\bar{X}$ control chart based on diverse alternative main and supplementary runs rules that is the most popular control chart for monitoring the mean of a process are proposed. This paper reviews and discusses the-state-of-art researches for these runs rules and classifies according to several properties of runs rules. ARL derivation for a proposed runs rule is also illustrated.

• Radiation Oncology Journal
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• v.37 no.1
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• pp.60-65
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• 2019

Purpose: The quality assurance (QA) chart rounds are multidisciplinary meetings to review radiation therapy (RT) treatment plans. This study focus on describing the changes in RT management based on QA round reviews in a single institution. Materials and Methods: After 9 full years of implementation, a retrospective review of all patients whose charts passed through departmental QA chart rounds from 2007 to 2015. The reviewed cases were presented for RT plan review; subcategorized based on decision in QA rounds into: approved, minor modifications or major modifications. Major modification defined as any substantial change which required patient re-simulation or re-planning prior to commencement of RT. Minor modification included treatment plan changes which didn't necessarily require RT re-planning. Results: Overall 7,149 RT treatment plans for different anatomical sites were reviewed at QA rounds. From these treatment plans, 6,654 (93%) were approved, 144 (2%) required minor modifications, while 351 (5%) required major modifications. Major modification included changes in: selected RT dose (96/351, 27%), target volume definition (127/351, 36%), organs-at-risk contouring (10/351, 3%), dose volume objectives/constraints criteria (90/351, 26%), and intent of treatment (28/351, 8%). The RT plans which required major modification according to the tumor subtype were as follows: head and neck (104/904, 12%), thoracic (12/199, 6%), gastrointestinal (33/687,5%), skin (5/106, 5%), genitourinary (16/359, 4%), breast (104/2387, 4%), central nervous system (36/846, 4%), sarcoma (11/277, 4%), pediatric (7/251, 3%), lymphoma (10/423, 2%), gynecological tumors (2/359, 1%), and others (11/351, 3%). Conclusion: Multi-disciplinary standardized QA chart rounds provide a comprehensive and an influential method on RT plans and/or treatment decisions.

• Communications for Statistical Applications and Methods
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• v.23 no.6
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• pp.497-515
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• 2016

Modern processes often monitor more than one quality characteristic that are referred to as multivariate statistical process control (MSPC) procedures. The MSPC is the most rapidly developing sector of statistical process control and increases interest in the simultaneous inspection of several related quality characteristics. Most multivariate detection procedures based on a multi-normality assumptions are independent, but there are many processes that assume non-normality and correlation. Many multivariate control charts have a lack of related joint distribution. Copulas are tool to construct multivariate modelling and formalizing the dependence structure between random variables and applied in several fields. From copula literature review, there are a few copula to apply in MSPC that have multivariate control charts, and represent a successful tool to identify an out-of-control process. This paper presents various types of copulas modelling for the multivariate control chart. The performance measures of the control chart are the average run length (ARL) and the average number of observations to signal (ANOS). Furthermore, a Monte Carlo simulation is shown when the observations were from an exponential distribution.

• The Journal of Pediatrics of Korean Medicine
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• v.36 no.4
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• pp.1-17
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• 2022

Y

• The Journal of Internal Korean Medicine
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• v.42 no.6
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• pp.1349-1355
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• 2021

Objectives: The aim of this study was to evaluate the effectiveness of additional administration of Banha-sasim-tang formulation to patients with gastrointestinal symptoms that did not improve with Western medicines. Methods: The patients who met the inclusion and exclusion criteria were analyzed retrospectively. A paired t-test was performed on the Nepean Dyspepsia Index-Korean version (NDI-K) scores before and after administering the Banha-sasim-tang formulation. Results: A total of 27 subjects were included. The mean duration of taking the Banha-sasim-tang formulation was 15.6±3.1 days. The most commonly used Western medicine before taking the Banha-sasim-tang formulation was rebamipide. The means of the NDI-K score were 57.4±21.8 before administering Banha-sasim-tang formulation and 34.9±16.5 after administration, and the difference was statistically significant (p<0.0001). No serious side effects were encountered while taking the Banha-sasim-tang formulation. Conclusions: For patients whose gastrointestinal symptoms do not improve with Western medicines, additional administration of Banha-sasim-tang formulation may be an option. However, as this study is a retrospective chart review, prospective, large-scale, double-blind studies are needed in the future.

• The Journal of Internal Korean Medicine
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• v.40 no.3
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• pp.478-490
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• 2019

Purpose: This work is a retrospective clinical case study evaluating the efficacy of Injinoryung-san granule administration to patients who showed an abnormal hepatic function test level. Methods: We analyzed the chart records of seven patients with elevated levels of the hepatic function test treated with Injinoryung-san granules. Results: The patients who were treated with Injinoryung-san showed a significant improvement in their elevated hepatic function test levels. Conclusion: In patients with elevated hepatic function test levels, Injinoryung-san granules can improve the hepatic level without adverse effects or changes in existing drugs.

• The Journal of Korean Medicine
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• v.37 no.1
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• pp.34-40
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• 2016

Objectives: To observe safety and efficacy of herbal medicine for psoriasis patients. Methods: We did retrospective chart review for 107 psoriasis patients who had been treated by herbal medicine for 2 months, and we analyzed the liver function test (LFT) results and Psoriasis Area and Severity Index (PASI) scores of before and after the treatment. Results: The mean LFT and the number of patients with abnormal LFT decreased after the treatments. More than 95% of patients with normal LFT maintained normal results at after the treatment, and only 2.1% and 4.6% patients with normal LFT showed abnormal Glutamic Oxaloacetic Transaminase (GOT) and Glutamic Pyruvic Transaminase (GPT) results at after the treatment. Also, both mean PASI scores for all patients and patients with abnormal LFT before the treatment decreased significantly. Conclusions: This study suggest that herbal medicine may be safe and effective treatment for psoriasis.