• Journal of the Ergonomics Society of Korea
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• v.29 no.5
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• pp.735-739
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• 2010

Driving workload is increasing according to developing new in-vehicle devices and introducing driving information systems. In this research using a driving simulator, EFRP (Eye Fixation Related Potential) was measured for evaluating driving attention and distraction while tasking cognitive workload, n-back tasks. The result of EFRP was compared with driver behaviors. Results suggest that EFRP is able to use for a method of evaluating driving workload, however, the analysis of driver behavior is difficult to find driving attention and distraction in the case of free flow of traffic situation.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.19 no.4
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• pp.98-107
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• 2005

Brushless DC motor(BLDCM) can be driven by 120[^{\circ}]$ square wave voltage and use PWM pulse patterns in two-phase feeding scheme to control the speed of the motor. This Paper introduces four PWM modes used BLDCM control system, and analyzes their different influences on the motor performances using a time-stepped voltage source finite element method. To verify the proposed computational method, we built the prototype motor for electrical power steering(EPS) and compared the predicted and the measured back EMF and phase current.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.56 no.7
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• pp.1224-1230
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• 2007

In this paper, we study the classification of defects at steam generator tube in nuclear power plant using eddy current testing (ECT). We consider 4 defect patterns of SG tube: I-In type, I-Out type, V-In type, and V-Out type. Through numerical analysis program based on finite element modeling, 400 ECT signals are generated by varying width and depth of each defect type. In order to improve the classification performance, we propose new feature extraction technique. After extracting new features from the generated ECT signals, multi-layer perceptron is used to classify the defect patterns. Through the computer simulation study, it is shown that the proposed method achieves 100% classification success rate while the previous method yields 91% success rate.

• 유체기계공업학회:학술대회논문집
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• 2006.08a
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• pp.487-488
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• 2006

In these days, demand of a LCD monitor is remarkably increasing with development of the LCD technology. However, there are thermal problems for improvement of efficiency for the LCD monitor. Thus, this research analyzed thermal problems such as convection and conduction heat transfer characteristics in the LCD monitor using an infrared (IR) camera. Also, the results of the outer side of the front LCD panel using the IR camera have been compared with the results of the inner side of the front panel using T-type thermocouples. The equations have been derived for the temperature distribution of the inner side of the front LCD panel by a multiple regression method including variables for ambient temperature, humidity and temperature differences between the front and back panels of the LCD monitor.

• Journal of the Korean Institute of Telematics and Electronics D
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• v.35D no.4
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• pp.24-31
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• 1998

The far-zone magnetic field patterns of a E-plane horn antenna with various edge structures are analyzed using UTD. The ray tracing method is used to lacate the shadow boundaries, and then GO and UTD are utilized to evaluate the incident, reflected, diffracted, surface diffaracted, and the second order diffracted, diffracted-reflected, and diffracted-reflected-diffracted waves existing in each region of interest. By doing this, we analyzed the effects of flanges or caps connected on the edge of a horn antenna on the side lobe and back lobe levels. Also, the validity of this paper is proved by comparing the analytical results with those of measurement and method of moment presented in the reference.

• Journal of the Korean Home Economics Association
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• v.32 no.5
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• pp.125-134
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• 1994

The Purpose of this study is to explore the conceptions of childhood and the practices about childrearing in the period of the Three States. The method used for this study is the historical method and the literatures of analysis are The Chronicles of the Three States and The Heritage of the Three States. According to the results the conceptions of childhood in its boundary were that the point at which childhood in its boundary were that the point at which childhood ended was the age of 15. And the conceptions of childhood in its demension were that the age of 10 was important demension epitemologically and the age of 15 was important in political dimension. Also there were several practices of childrearing in the Three States. First the sweddling clothes were in use. Second a child was carried on adult's back. Third parents paryed for giving birth to their child and had a dream of conception. finally there were th child welfare works. Through this study we can have access to the understanding about cultural transmission process of childrearing in Korea.

• International Journal of Contents
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• v.7 no.3
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• pp.1-5
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• 2011

It has been an interesting challenge to find a good classifier for imbalanced data, since it is pervasive but a difficult problem to solve. However, classifiers developed with the assumption of well-balanced class distributions show poor classification performance for the imbalanced data. Among many approaches to the imbalanced data problems, the algorithmic level approach is attractive because it can be applied to the other approaches such as data level or ensemble approaches. Especially, the error back-propagation algorithm using the target node method, which can change the amount of weight-updating with regards to the target node of each class, attains good performances in the imbalanced data problems. In this paper, we analyze the relationship between two optimal outputs of neural network classifier trained with the target node method. Also, the optimal relationship is compared with those of the other error function methods such as mean-squared error and the n-th order extension of cross-entropy error. The analyses are verified through simulations on a thyroid data set.

• Journal of the Korean Home Economics Association
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• v.32 no.4
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• pp.149-162
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• 1994

The Purpose of this study is to explore the conceptions and the practices about childreariong in the Koryo Dynasty(918-1392 A, D). The method used for this study is the historical method and the literatures of analysis are the Koryo Dynasty History. According to the results the conceptions of childhood in its boundary were that the point at which childhood ended was the age of 15, which was sud-devided into three of different periods. And the conceptions of childhood in its nature and its ideal traits were that child's ability was determinated innately and intellectual features and mutual understanding of others were emphasized as its ideal traits. Also the practices of childrearing in Koryo Dynasty were that a child was carried on adult's back, and that parents prayed for giving birth to their child and finally that the role expectation toward childrearing was affectionate caring. Moreover there were the child welfare work and the educational system in Koryo Dynasty. Through this study, we can have access to the understanding about cultural transmission process of childrearing in Korea.

• Communications of the Korean Mathematical Society
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• v.14 no.4
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• pp.815-832
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• 1999

High-order weighted difference schemes with uniform meshes are considered for the convection-diffusion problem depending on Reynolds numbers. For small Reynolds numbers, a weighed cen-tral difference scheme is suggested since there is no boundary layer. For large Reynolds numbers, we propose a modified up wind method with an artificial diffusion in order to overcome nonphysical oscilla-tion of central schemes and obtain good accuracy in the boundary later. Existence and corresponding error estimates of the solution for the difference scheme have been shown. Numerical experiments are provided to back up the analysis.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2009.01a
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• pp.446-449
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• 2009

In this paper, we present a novel method for reconstructing a super-resolution image using multi-view low-resolution images captured for depth varying scene without requiring complex analysis such as depth estimation and feature matching. The proposed method is based on the iterative back projection technique that is extended to the 3D volume domain (i.e., space + depth), unlike the conventional superresolution methods that handle only 2D translation among captured images.