• 한국항공운항학회지
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• 제26권1호
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• pp.1-9
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• 2018

Ground effect includes a reduction of induced drag, increase of lift, and nose-down moment during landing. These phenomena, occurring late in the landing maneuver, are considered to be of little significance because they tend to counteract and/or compensate in this respect. Even though it is unlikely to affect any flare profile variations appreciably, some pilots have reversed perception about such phenomenon and overestimate during landing. It is becoming a negative factor and is making an adverse effect on landing maneuver. This study examines the perception of ground effect of large aircraft pilots, reviews literature regarding ground effect, and makes suggestions that pilots can correctly recognize and respond to the effect during landing flare maneuvers.

• 대한산업공학회지
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• 제21권3호
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• pp.371-385
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• 1995

The yield of semiconductor chips is dependent not only on the average defect density but also on the distribution of defects over a wafer. The distribution of defects leads to consider a cluster index. This paper briefly reviews the existing yield prediction models ad proposes a new cluster index, which utilizes the information about the defect location on a wafer in terms of the coefficient of variation. An extensive simulation is performed under a variety of defect distributions and a yield prediction model is derived through the regression analysis to relate the yield with the proposed cluster index and the average number of defects per chip. The performance of the proposed simulation-based yield prediction model is compared with that of the well-known negative binomial model.

• 품질경영학회지
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• 제27권3호
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• pp.1-16
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• 1999

According to the study of TQM implementations, the odds that an organization will successfully implement total quality management are two to one-against it. Based on the Brown's study, two thirds of all TQM implementations are dropped or fail altogether. However, organizations armed with knowledge of the factors that have the biggest impact on their success can take steps to influence or change those factors. In this paper, we studied on the degree of influence between those factors and successful start up and alignment factors. Based on extensive literature reviews those factors, threat, commitment, plan, progress and strategy are determined. Also we determine the successful start up and alignment factors. A framework of research including above factors is developed and tested statistically The Perceived data are collected from managers of quality departments of 141 Korean firms through survey. The results show that the rating of those factors which determine success of implementing TQM is progress, commitment, strategy and progress. But the factor of threat shows negative influence for the success of implementing TQM.

• 지식경영연구
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• 제10권2호
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• pp.1-14
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• 2009

This study has investigated the effects of promoting and inhibiting factors on information sharing between buyers and sellers in Korean distribution industry. Based on intensive literature reviews, eight promoting factors(satisfaction, relational norms, trust, commitment, fairness, formalization, participation, transaction specific investment) and five inhibiting factors(opportunism, environmental uncertainty, conflict, concentration, monitoring) were included in the research model. For the purpose of empirical testing, 320 respondents of retailers in Korea were surveyed and the analysis utilizing structural equation model indicated that satisfaction, relational norms, trust, commitment, fairness, formalization, and participation had positive effects on information sharing. And concentration and monitoring had negative effects on it. However transaction specific investment, opportunism, conflict, and environmental uncertainty had no significant effects.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• 제21권3호
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• pp.141-146
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• 2010

This summary of literature during the past year reviews published studies relating to risk factors for depressive disorders in children and adolescents. Risk factors include environmental toxins, socio-environmental, and genetic factors. As depression has a complex, multifactorial causal mechanism, it is likely that the accumulation and/ or interaction among multiple risk factors lead to depression. Findings related to the result of toxin exposure have been difficult to interpret given that risk factors tend to interact and that higher mental functions are not easily measurable. However, some findings have been consistent. Clinical research data has also shown that the risk for negative outcomes may be modified both by genetic and environmental factors through a gene environment interplay mechanism.

• 해양환경안전학회지
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• 제8권2호
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• pp.61-69
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• 2002

The relatively rapid rising trend of crime rates in marine situations leads to social concerns in Korea. This study reviews some theoretical backgrounds of the economics of crime and applies econometric models to Korean marine crimes. This research finds that there is a negative relationship between marine crime rates and unemployment rates and a positive relationship between the price level and marine crimes in Korea. The other finding results are that unemployment elasticities are higher in the 1980s and price elasticities are higher in th 1990s in comparison with the results of the other periods. This findings are incompatible with the previous theoretical researches in advanced countries. These findings show that In rapidly growing economy, marine crime occurrence is proportional to marine economic activity frequency. This result may reflect that marine crimes are different from land crimes.

• 한국시스템다이내믹스연구
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• 제13권4호
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• pp.5-31
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• 2012

This paper aims at investigating the dynamics between aging population and local finance. In recent years, the aging rate has been accelerating the pace. The trend implies that Korea is moving towards the aging society, presumably, with unprecedented speed in the world. Aging society's biggest problems are centered around the explosive growth of the financial needs. In particular, these problems are apt to appear more seriously in local governments, as most of them are confronted with high level of aging population and poor financial bases. Firstly, it analyzes how the population structure in the local government impacts local finance, income and expenditure. Based upon in-depth literature reviews, this study examines variables related to aging population and local fiance. Secondly, it focuses on a series of positive and negative feedback loops which would reveal the essence of the mutual interaction structure between aging population and local governments' fiscal behaviors.

• 한국언어정보학회:학술대회논문집
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• 한국언어정보학회 2007년도 정기학술대회
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• pp.481-488
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• 2007

In this paper, we propose a method to classify movie review documents into positive or negative opinions. There are several approaches to classify documents. The previous studies, however, used only a single classifier for the classification task. We describe a multiple classifier for the review document classification task. The method consists of three classifiers based on SVMs, ME and score calculation. We apply two voting methods and SVMs to the integration process of single classifiers. The integrated methods improved the accuracy as compared with the three single classifiers. The experimental results show the effectiveness of our method.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제9권8호
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• pp.3169-3181
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• 2015

Nowadays, online word-of-mouth has become a powerful influencer to marketing and sales in business. Opinion mining and sentiment analysis is frequently adopted at market research and business analytics field for analyzing word-of-mouth content. However, there still remain several challengeable areas for 1) sentiment analysis aiming for Korean word-of-mouth content in film market, 2) availability of machine learning models only using linguistic features, 3) effect of the size of the feature set. This study took a sample of 10,000 movie reviews which had posted extremely negative/positive rating in a movie portal site, and conducted sentiment analysis with four machine learning algorithms: naïve Bayesian, decision tree, neural network, and support vector machines. We found neural network and support vector machine produced better accuracy than naïve Bayesian and decision tree on every size of the feature set. Besides, the performance of them was boosting with increasing of the feature set size.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제12권8호
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• pp.4090-4102
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• 2018

After emerging online communications, text mining and sentiment analysis has been frequently applied into analyzing electronic word-of-mouth. This study aims to develop a domain-specific lexicon of sentiment analysis to predict box office success in Korea film market and validate the feasibility of the lexicon. Natural language processing, a machine learning algorithm, and a lexicon-based sentiment classification method are employed. To create a movie domain sentiment lexicon, 233,631 reviews of 147 movies with popularity ratings is collected by a XML crawling package in R program. We accomplished 81.69% accuracy in sentiment classification by the Korean sentiment dictionary including 706 negative words and 617 positive words. The result showed a stronger positive relationship with box office success and consumers' sentiment as well as a significant positive effect in the linear regression for the predicting model. In addition, it reveals emotion in the user-generated content can be a more accurate clue to predict business success.