• Proceedings of the KIPE Conference
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• 2002.07a
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• pp.701-706
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• 2002

Typically, dimensions of the power circuit depend on magnetic components, heat sink, and smoothing capacitor, etc. For the miniaturization of the power circuit, one of the solutions is that bulky magnetic transformer in previously used is replaced by a piezoelectric transformer. Therefore, since many systems are attempted to apply the piezoelectric transformers, a new piezoelectric material is tending to be developed continuously. In this paper, an analysis of neon tube inverters with piezoelectric transformers are presented by Pspice modeling. Simulation results show that it is possible to apply a piezoelectric transformer to neon tube inverters with high conversion efficiency

• Journal of the Korean Operations Research and Management Science Society
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• v.20 no.2
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• pp.109-123
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• 1995

Weight of the factors to be considered in layout development with improvement-type heuristics is discussed in this paper. Determination of weight is especially important if it is designed to be used with an improvement-type heuristic. It is same as the value of variable coefficients in a multi-objective function as well as indices for departmental switching orders in the heuristic. Various weights are examined through computer simulation to verify whether the numerical values collected from machinery industries can be used as weights. And then a method to be used for searching an optimum or optimum-tending layout for machinery industries is presented using the weight.

• Journal of the Korean Data and Information Science Society
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• v.19 no.4
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• pp.1037-1046
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• 2008

Recently, the oil suppliers who supply the tax-exempt oil to the fishery are confronted with big trouble in their supply and demand system due to the unstable global oil prices. We applied the seasonal ARIMA(SARIMA) model to the low-sulfur and high-sulfur crude oil which are in great request and developed forecasting systems for them. Since there are many parameters in SARIMA, it is difficult to estimate the optimal parameters, but it is overcome by using simulation looping program. In conclusion, we found that the obvious seasonality in demand of low-sulfur and these demands are tending downwards gradually.

• Proceedings of the Korean Geotechical Society Conference
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• 2008.10a
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• pp.1689-1692
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• 2008

In this research, these days extension of electric power station plant and new building plan is tending to more bigger size and much more cooling water for discharge, therefore submarine structure for discharge has needed various types and the large one. The domestic power plant was applied to once-through CW system structure that pipe line type, immersed PC-box culvert type and submarine headrace tunnel type of discharge structure. It is possible that the future structure type of submarine discharge is expected by a case research of application and plan.

• Korean Institute of Interior Design Journal
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• v.15 no.6 s.59
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• pp.255-263
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• 2006

This research analyze the demand of the residents against the public housing remodeling of national housing scale $(85m^2)$, focusing on residents and their tendencies within their dwelling spaces. The analysis determines the most appropriate patterns and spatial connections within the floor plan. The result includes that there are two types of the classification into an urban oriented propensity (45%), 'The center of city, the apartment and the convenience' etc, and a rural oriented propensity (55%), 'The pastoral, the house and the circumstance' etc, based on their lifestyle values. Also there are three interior propensity classifications, those tending to warm and sensitive variable space (42%), western and gorgeous dynamic space (34%) and oriental and popular static space (24%). The research illustrated the residents' desired space planning options, based on the analysis of the residents' preference patterns which is various.

• Journal of the Korea Safety Management & Science
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• v.12 no.3
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• pp.73-79
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• 2010

Currently, in Korea, an accident that takes place during a worker's commuting is generally not considered as work-related accident. However, there are several exceptions such as an accident that occurs in commuting while using transportation provided by an employer, an accident that happens during commuting time that can be regarded as part of a business activity (e.g. tending to work instructed by an employer on the way to or from work), and an accident that is caused by insufficient facility management by an employer. It is even more so as the workers' commuting distance increases with expanding scale of a city, and traffic accident occurs more frequent. Social risk of commuting-time accident is on the rise. Under this circumstance, it is an important social issue to explore how to protect workers from commuting-time accident.

• International Commerce and Information Review
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• v.9 no.3
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• pp.255-271
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• 2007

It is widely acknowledged that Chinese economy becomes a center of world economy and takes up a considerable portion of the trade in Northeastern Asia. Due to the investment and the logistics modernization strategy of Chinese government, recognizing the importance of logistics, the competitiveness of Chinese major ports is tending upward rapidly. Therefore, it is necessary to analyze the competitiveness of Chinese major ports in order to develop the logistics strategy of Korea by cooperating or competing with Chinese ports. In this study, we analyzed the competitiveness of 10 major Chinese ports with Data Envelopment Analysis(DEA). Through the analysis, we could investigate the efficiency of 10 major Chinese ports and figure out the trend of the efficiency within recent 10 years. In order for Korea to achieve the national strategic goal, becoming a logistics hub in East Asia, it is obvious to understand the competitiveness of Chinese major ports which are major competitor and strategic partner at the same time. This study will be useful to understand the competitiveness of Chinese ports and to develop a logistics hub strategy of Korea.

• Journal of Society of Preventive Korean Medicine
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• v.8 no.1
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• pp.155-161
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• 2004

The average life span is expanded due to the development of modem society, material and cultural life and increasing level of public health. This means that the aging society is rapidly progressing. Geniatric diseases also have increased due to increasing of the aged population. Along with an increase of the aged patient, the anti-aging, prevention of geniatric disease and quality of life is tending high on social concern and medical issues. Many reports showed the evidence to the positive anti-aging effect of Oriental medicine. Qigong therapy, a kind of Oriental medicine, has been used to prevent aging and life prolongation with positive effect for many thousand years. Therefore, qigong practice is popular and common to middle age and old age in China.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.20 no.6
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• pp.1948-1958
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• 1996

Experimental and theoretical studies on the air-assist coaxial atomizer have been continuously carried out for a long time. But now the importance of the theoretical study is tending to increase as with the development of computer. This study is concerned to the spray modelization, especially, the instability of the liquid jet surrounded by the air stream which flows with high velocity. To study the phenomena of the break up, we used the linear theory based on the classical Kelvin-Helmholtz theory for capillary wave at a simple interface and we investigated the variation of liquid core radius. As a result, we obtained that the drop diameter and the variation of the liquid core radius predicted by using our model are reasonable.

• Communications for Statistical Applications and Methods
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• v.28 no.1
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• pp.21-37
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• 2021

There is a direct connection between linear discriminant analysis (LDA) and linear regression since the direction vector of the LDA can be obtained by the least square estimation. The connection motivates the penalized LDA when the model is high-dimensional where the number of predictive variables is larger than the sample size. In this paper, we study the penalized LDA for a class of penalties, called the moderately clipped LASSO (MCL), which interpolates between the least absolute shrinkage and selection operator (LASSO) and minimax concave penalty. We prove that the MCL penalized LDA correctly identifies the sparsity of the Bayes direction vector with probability tending to one, which is supported by better finite sample performance than LASSO based on concrete numerical studies.