• 대한전기학회논문지:전력기술부문A
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• 제48권2호
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• pp.119-126
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• 1999

Current transformer (CT) saturation may cause a variety of protective relays to malfunction. The conventional CT is designed that it can carry up to 20 times the rated current without exceeding 10% ratio error. However, the possibility of CT saturation still remains if the fault current contains substantial amounts of ac and/or dc components. This paper presents a design method of iron-cored CTs for use with protective relays to prevent CT saturation. The proposed design method determines the core cross section of the CT; it employs the transient dimensioning factor to consider relay's operating time (duty cycle) and dc component as well as ac components contained in the fault current, and symmetrical short-circuit current factor to consider as well as ac components contained in the fault current, and symmetrical short-circuit current factor to consider the biggest fault current. The method designs the cross section of CTs in cases of reclosure and no reclosure.

• Journal of the Korean Data and Information Science Society
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• 제17권4호
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• pp.1329-1341
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• 2006

When X and Y have independent gamma distributions, we consider the testing problem for two gamma means. We propose a solution based on a Bayesian model selection procedure to this problem in which no subjective input is considered. The reference prior is derived. Using the derived reference prior, we compute the fractional Bayes factor and the intrinsic Bayes factors. The posterior probability of each model is used as a model selection tool. Simulation study and a real data example are provided.

• 한국신뢰성학회지:신뢰성응용연구
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• 제10권1호
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• pp.25-38
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• 2010

In this paper, an accelerated degradation test procedure for an electronic appliance compressor is proposed. We investigate the amount of wear of the compressor and consider several factors as accelerating factors. Finally we select the operating pressure as a main accelerating factor. The test condition of accelerated degradation test is determined. The modified accelerating test reduces the test time in design phase by using the suggested accelerating factor.

• 대한음성학회지:말소리
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• 제67호
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• pp.79-102
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• 2008

In this paper, we investigate the relation between Bayes factor and likelihood ratio test (LRT) approaches and apply the neighborhood information of Bayes factor to building an alternate hypothesis model of the LRT system. To consider the neighborhood approaches, we contemplate a distance measure between models and algorithms to be applied. We also evaluate several methods to improve performance of utterance verification using neighborhood information. Among these methods, the system which adopts anti-models built by collecting mixtures of neighborhood models obtains maximum error rate reduction of 17% compared to the baseline, linear and weighted combination of neighborhood models.

• Journal of the Korean Data and Information Science Society
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• 제17권3호
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• pp.843-850
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• 2006

In this paper, we consider the Bayesian multiple comparisons problem for K bivariate exponential populations to make inferences on the relationships among the parameters based on observations. And we suggest the Bayesian procedure based on fractional Bayes factor when noninformative priors are applied for the parameters. Also, we give a numerical examples to illustrate our procedure.

• 한국의류학회지
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• 제31권8호
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• pp.1310-1320
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• 2007

This study investigated the differences in the importance of store characteristics depending on on-line clothing store type and consumer age. The questionnaires were given to female residents in the ages between 20-39 in Seoul and Kyung-gi province during October 2006. The results were summarized as follows: 1. By analyzing the differences in importances of on-line store characteristics factors it was found that buying process service factor and product searching system factor were important in on-line general merchandise store. and buying process service factor and product factor(all the factors, such as store credit, product, screen-displayed design, searching and approaching system, customer management service) were important in on-line specialty store. 2. By analyzing the differences in importances of on-line store characteristics depending on the store type, buying process system such as refund policy, shipping, high-speed payment and rapid searching, screen-displayed design system, approaching and searching system were more important in on-line general merchandise store when comparing to specialty store. It also showed that the consumer considered the reputation of the store and its image more important in on-line general merchandise store. 3. By analyzing the differences in of on-line clothing store importance depending on age, in the case of on-line general merchandise store, it showed that people in their thirties regarded buying process service factor more important than twenties, and when it came to the product and searching system, it was vice versa. Twenties had a tendency to consider the aspect of product important and, relatively, thirties regarded searching and approaching system factor important. in the case of specialty store. It was found that women in their twenties had a tendency to consider product factor more important.

• 대한물리치료과학회지
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• 제18권2호
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• pp.9-15
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• 2011

Purpose: The purpose of this study was to provide the information of renal disease patients and to provide evidence the physical therapy recipient of renal disease patients. The reviews suggest that renal disease patients are physical inactivity situation, increase on cardiopulmonary risk factor, developed complication disease, increased psychosocial factor like depress and anxiety, decreased Quality of life because their disease effects. Thus. exercise program seems to have beneficial effect on physiologic and psychosocial functioning, Quality of life. It is expected that this study will consider rehabilitation program for internal medicine patients and should be consider as availability of therapeutic exercise program on understanding renal disease in physical therapy.

• 한국조리학회지
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• 제11권1호
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• pp.87-104
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• 2005

A lifestyle changes according to environment. It appears more in the dietary life connected with the necessities in life. This study is executed empirically through the questionnaire that consists of selection attribute and variables connected with "well-being" that is examined in empirical analysis. It was carried out for 20 days from July 15 to August 5, 2003 with the customers who live in Seoul and the suburbs. With collected data, there were frequency analysis and factor analysis, reliability analysis using SPSS 10.0 packages, and T-test and ANOVA were enforced for the verification of differences between demographic elements with each factor. The result indicates that the inclinations of customers changed from the "well-being" trend have four factors: health consideration factor, food materials factor, cooking factor, and habit factor. And the housewife group shows the great changes in habit factor. In case of the changes according to incomes, the larger income earners tend to consider health more. In conclusion, people came to prefer the healthy Korean style food from the well-being trend.

• 한국컴퓨터정보학회논문지
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• 제12권5호
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• pp.215-223
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• 2007

온라인 쇼핑몰에 대한 관심이 높아지면서 다양한 연구가 진행되어 왔다. 그러나 대부분의 연구들은 인터넷의 특성을 고려하지 않은 채 오프라인 시장의 서비스품질 측정 도구를 그대로 적용하고 있다. 이에 본 연구에서는 기존 상거래에서처럼 환경적인 요소도 고객만족에 영향을 미치는 요인으로 고려하여 시스템품질로 규정하고, 서비스품질과 더불어 고객만족과의 관계를 파악하는 것이 중요하다고 보았다. 즉, 시스템품질과 서비스품질 중 어느 품질 요인이 고객만족에 더 많은 영향을 미치는지를 살펴보고, 시스템품질 요인과 서비스품질 요인과 고객만족 요인인 타인에게 적극적으로 쇼핑몰을 추천하는 애호도와 전환성과 어떤 관계가 있는지를 살펴본 후 이에 따라 고령친화용품을 중심으로 다양한 고객의 욕구를 충족시키는데 필요한 품질전략을 제시하고자 하였다.

• 응용통계연구
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• 제35권2호
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• pp.189-201
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• 2022

본 연구는 외부 요인을 모형에 강화시켜 암호화폐 수익률 예측력을 향상시키는 방법에 대해서 다루고 있다. 고려한 요인으로는 크게 나누어 금융 경제적 요인 및 심리적 요인을 고려하였다. 먼저 금융 경제적 요인을 반용하기 위해서 주성분 요인을 사용하여 수 많은 변수를 차원축소를 통해서 모형에 반영하였다. 또한 심리적 요인을 위해서는 뉴스 기사 데이터를 활용하여 산출해낸 감성지수를 활용하였다. 이러한 요인들은 충격반응함수 분석을 통해서 요인들의 의미와 영향력을 시각화하였다. 또한 전통적인 ARIMAX 뿐 만 아니라 랜덤포레스트 및 딥러닝 모형을 활용하여 비선형성을 반영하였다. 그 결과 요인 강화가 암호화폐 수익률 예측력을 향상시킴을 실증분석을 통해 밝혔으며 그 중에서 딥러닝 모형인 GRU가 가장 좋은 예측 성능을 보임을 관찰하였다.