• Industrial Engineering and Management Systems
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• 제8권3호
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• pp.139-147
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• 2009

Control charts are used to distinguish between chance and assignable causes in the variability of quality characteristics. When a control chart signals that an assignable cause is present, process engineers must initiate a search for the assignable cause of the process disturbance. Identifying the time of a process change could lead to simplifying the search for the assignable cause and less process down time, as well as help to reduce the probability of incorrectly identifying the assignable cause. The change point estimation by likelihood theory and the built-in change point estimation in a control chart have been discussed until now. In this article, we discuss two kinds of process change point estimation when the CUSUM ($\bar{x}$, s) control chart for monitoring process mean and variance simultaneously is operated. Throughout some numerical experiments about the performance of the change point estimation, the change point estimation techniques in the CUSUM ($\bar{x}$, s) control chart are considered.

• 한국초등과학교육학회지:초등과학교육
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• 제17권1호
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• pp.23-32
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• 1998

A good example of the persistence of naive theories about change in seasons is well knowned: A filmmaker carried a camera into the crowd of gowned graduates at the 1987 commencement of Harvard University and asked a simple question, that is, "Why is it hotter in summer than in winter?" to twenty five students chosen at random. All of the answers except two were that the Earth is closer to the Sun in summer, so it is hotter in summer, but the Earth is farther from the Sun in winter, so it is cooler in winter. Until now, naive theories about the cause in seasons have been extensively studied. However, few studies to overcome these naive theories were reported. Author takes two steps: first, a new model on the cause in seasons is developed. Second, preservice students concepts' change on the cause in seasons through the new model is observed. The author concludes that the new model have a good effect on the preservice students concepts' change on the cause in seasons.

• 한국화재소방학회논문지
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• 제29권5호
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• pp.57-66
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• 2015

본 논문은 단자대에서 단일원인 및 복합원인에 의한 전기화재위험성을 규명하기 위한 연구이다. 우선적으로 단일원인인 접촉불량에 의한 화재위험성을 측정하기 위해 조임토크변화 및 접촉저항변화에 따른 열적특성을 분석하였다. 또한, 복합원인에 의한 화재위험성을 측정하기 위해 접촉저항변화에 따른 가속트래킹 실험을 실시하여 접촉불량과 트래킹의 화재연관성을 확인하였다. 실험결과 단일원인의 경우 접촉불량상태의 조임토크 및 접촉저항 크기가 증가할수록 열적특성이 뚜렷하게 나타나는 것을 확인할 수 있었고, 접촉저항변화에 따른 열적특성이 조임토크변화에 따른 열적특성보다 그 특성이 더 잘 나타났다. 또한, 복합원인의 경우 단자대 접촉불량과 트래킹은 상호연관성을 가지고 있으며, 두 가지의 복합적인 원인이 서로 작용될 경우 기존의 단일원인의 전기화재 위험성보다 상대적인 위험성이 더욱 높게 나타나는 것으로 도출되었다.

• 한국초등과학교육학회지:초등과학교육
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• 제30권2호
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• pp.204-212
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• 2011

This research is about the six graders' preconceptions in elementary school about a cause of the seasonal change before learning. The result of this research is that the patterns of six graders's preconceptions in elementary school are earth's rotation, earth's revolution, the distance between the earth and the sun and the location factor between the sun and our country, which are mixed up with two more things. Especially many patterns of students explain the seasonal change of our country using the change of location of our country by earth's rotation, the location factor between the earth and the sun and the distance between the earth and the sun by earth's revolution.

• 한국품질경영학회:학술대회논문집
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• 한국품질경영학회 2004년도 품질경영모델을 통한 가치 창출
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• pp.436-441
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• 2004

Knowing the time of the process change could lead to quicker identification of the responsible special cause and less process down time, and it could help to reduce the probability of incorrectly identifying the special cause. In this paper, we propose a generalized maximum likelihood estimate. (MLE) of the process change point when a control chart with variable sample size (VSS) scheme signals a change in the process mean, and evaluate the performance of this estimator when it mi used with a VSS EWMA chart.

• 복식
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• 제51권3호
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• pp.141-153
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• 2001

The Purpose of this research is to compare the feminine modesties expressed in the clothes of women's college students in 1980s and 1990s, and to find out the social cause of the change of modesty by reference data. Korean women's college students in 1980s considered feminine modesty very important in the selection of clothes but students in 1990's had quite different attitudes. The major cause of this change may be due to the fact that the traditional conservative values in clothes were diminished in 1990's. The main cause of different values in 1980s and 1990s is the rapid social change of korean society in this Period. The concrete factors of changes were the change of authoritarian aesthetic values and the Positive orientation to diversity individuality sensibility and sexuality.

• 해양안보
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• 제1권1호
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• pp.31-59
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• 2020

본 연구의 목적은 왜 러시아가 카스피해 협약에서 카스피해 횡단 노선을 허용하는 방향으로 입장을 전환하였는지를 밝히는 데 있다. 러시아의 유라시아 통합에 대한 입장 변화를 설명하는 이론은 변화의 원인으로 서방으로부터의 고립과 아시아-태평양의 정치·경제적 중요성 상승을 제시하지만, 서방의 영향력을 허용할 수 있는 입장 변화의 원인은 설명하지 못한다. 따라서 본 연구에서는 러시아의 카스피해 입장 변화의 원인으로 유라시아 개발에 따른 유라시아 영향력 확대에 대한 인식의 변화를 제시한다.

• 한국통계학회:학술대회논문집
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• 한국통계학회 2005년도 춘계 학술발표회 논문집
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• pp.191-196
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• 2005

Knowing the time of the process change could lead to quicker identification of the responsible special cause and less process down time, and it could help to reduce the probability of incorrectly identifying the special cause. In this paper, we propose a MLE of the process change point when control charts with the fixed sampling rate (FSR) scheme or the variable sampling rate (VSR) scheme monitor a process to detect changes in the process mean and/or variance of a normal quality variable.

• 대한한의학원전학회지
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• 제20권4호
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• pp.251-265
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• 2007

This study is a research on the etiology in Wu Youke's wenyi theory. In regard to the etiology of epidemic disease that had been spread on a very large scale at that time, Wu Youke denied the traditional theory which urged the irregular change of climate as the cause of epidemic disease, and proposed the concept of 'zaqi' which was considered by him to be something that could be the real cause of epidemic disease. And He treated the wenyi disease as something that has the same meaning with wenbing, so his concept on wenbing was basically the thing that treats 'zaqi' as the fundamental cause of wenbing and treats the concept of 'wen(溫)' as an environmental cause that could help activate the virulence of 'zaqi'. Such concept like this was the thing somewhat different from the traditional etiological theory that considers the change of climate as the principal cause of waigan(外感)-disease, and it must for the most part have been originated from the experience of Wu Youke himself. But this study, in contrast, based on the thing he denied the traditional theory on the irregular change of climate, has been done in the point of view that fundamental concept of his wenyi theory such as 'zaqi' was not only originated from his clinical experience but also from the influence of paradigm shift in the natural philosophy of that time. There had been so much change in cosmology and natural philosophy from the fundamental basis at that time, and the the most principal concept of it was that there always exists irregular faces in the change of nature. Such concept like this got into its stride from about 17th century, and it was expressed in the form of the severe criticism against the traditional natural philosophy. In regard to this, this study has outlined the academic thought of the leading scholars who made a significant progress in such a paradigm shift, and it includes the scholars like Wang Tingxiang, Wang Fuzhi, Hu Wei, Huang Zongxi, who played their role in the time of the latter period of Ming dynasty and the former period of Qing dynasty.

• Communications for Statistical Applications and Methods
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• 제10권3호
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• pp.825-833
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• 2003

Knowing the time of the process change could lead to quicker identification of the responsible special cause and less process down time, and it could help to reduce the probability of incorrectly identifying the special cause. In this paper, we propose a maximum likelihood estimator of the process change point when a Shewhart $\bar{X}$ chart with variable sample size (VSS) scheme signals a change in the process mean. Also we build a confidence interval for the process change point by using the likelihood function.