• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2008.04a
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• pp.653-658
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• 2008

LCVA has an advantage that its natural frequency can be easily controlled by changing the area ratio of the vertical column and horizontal part. The previous studies investigated the dynamic characteristics of the LCVA under harmonic load. This study experimentally obtained the first and second mode natural frequencies of the LCVA from shaking table tests using white noise and compared the values with the ones by previous study. Test results show that the measured first mode natural frequency of the LCVA has a different value compared with calculated one. The effective length($L_e$) was revised using by power equation. In the Case01 to 19, the standard deviation($s_r$) is 4.7292 and the coefficient of correlation(r) is 0.9856. In the Case21 to 61, the standard deviation ($s_r$) is 14.2143 and the coefficient of correlation(r) is 0.9935. The second mode frequency increases with the increasing area ratio, which is due to the sloshing motion effect resulting from the large area of the vertical column.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.19 no.2
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• pp.119-126
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• 2009

LCVA has an advantage that its natural frequency can be easily controlled by changing the area ratio of the vertical column and horizontal part. The previous studies investigated the dynamic characteristics of the LCVA under harmonic load. This study experimentally obtained the first and second mode natural frequencies of the LCVA from shaking table tests using white noise and compared the values with the ones by previous study. Test results show that the measured first mode natural frequency of the LCVA has a different value compared with calculated one. The effective length($L_e$) was revised using by power equation. In the case01 to 19, the standard deviation($S_r$) is 4.7292 and the coefficient of correlation(r) is 0.9856. In the case21 to 61, the standard deviation($S_r$) is 14.2143 and the coefficient of correlation(r) is 0.9935. The second mode frequency increases with the increasing area ratio, which is due to the sloshing motion effect resulting from the large area of the vertical column.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.27 no.6C
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• pp.619-624
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• 2002

In this paper, a novel architecture of programmable divider with fifty percent duty cycle output and programmable dividing number has been proposed. Through HSPICE simulation, a 900MHz frequency synthesizer with proposed (sequency divider has designed in a standard 0.25㎛ CMOS technology To verify the operation of proposed frequency divider, a chip had been fabricated using 0.65㎛ 2-poly, 3-metal standard CMOS processing and experimental result shows that the proposed frequency divider works well. The designed voltage controlled oscillator(VCO) has a center frequency of 900MHz a tuning range of $\pm$10%, and a gain of 154HHz/V. The simulated frequency synthesizer performance has a settling time of 1.5$\mu$s, a frequency range from 820MHz to IGHz and power consumption of 70mW at 2.5V power supply voltage.

• Journal of Drive and Control
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• v.15 no.4
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• pp.1-10
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• 2018

Spool displacement of a direction control valve is the standard signal to measure the bandwidth frequency of the direction control valve. When the spool displacement signal is not available, it is suggested in this study to use the metering hydraulic line as an alternative way to measure - 90 degree phase bandwidth frequency of the hydraulic direction control valve. Dynamics of the hydraulic line is composed of inertia, capacitance, and friction effects. The effect of oil inertia is dominant in common hydraulic line dynamics and the line dynamics is close to a derivative action in a range of high frequency; such as a range of bandwidth frequency of common directional control valves. Phase difference between spool displacement and line load pressure is nearly constant as a valve close to 90 degree. If phase difference is compensated from the phase between valve input and pressure, compensated phase may be almost same as the phase of spool displacement that is a standard signal to measure phase bandwidth frequency of the directional control valve. A series of experiments were conducted to examine the possibility of using line pressure in to measure phase bandwidth frequency of a directional control valve. Phase bandwidth frequency could be measured with relatively high precision based on metering hydraulic line technique and it reveals consistent results even when valve input, oil temperature, and supply pressure change.

• Journal of Nutrition and Health
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• v.33 no.3
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• pp.314-324
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• 2000

Evaluation of nutritional status of the elderly imposes different problem from the other age groups. It is essential to use right instrument to assess food consumption. In Korea, the food frequency questionnaire has not been applied widely to elderly people. The purpose of this study is to assess the possibility of employing a semi-quantitative food frequency questionnaire(FFQ) for the Korean elderly to estimate nutrient and/or food intakes. In this study the FFQ for the elderly was developed and validated. The subjects were 144 free-living old women aged from 65 to 90. The FFQ was designed with 4 items for cereals and 86 items for other foods and with frequency of 12 intervals. Three portion sizes were given to select : 1/2 of standard amount, standard amount, and 11/2 of standard amount. ach subject was interviewed with newly developed FFQ form and same subjects were also involved to complete 3-day diet record. Nutrient intake was calculated using software program developed by our group. The nutrient intakes by the FFQ was validated by comparing the results with 3-day diet record. The FFQ estimated significantly higher mean intakes of energy, carbohydrate, protein, fats and vitamin C than did the diet reconrds(p<0.05). Pearson's correlation coefficients between two methods ranged from 0.21 for vitamin Q to 0.69 for alcohol(mean r=0.53). From 32% to 42% of the subjects were classified in the same quintile of nutrient intake by two methods, and 63% to 84% were classified in the same or adjacent quintile. On average, only 4% of the subjects were misclassified into extreme quitiles. The results indicate that the FFQ developed for the elderly in this study is useful for classifying individuals by rank and identifying groups at extremes of nutrient intakes.

• Journal of Physiology & Pathology in Korean Medicine
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• v.22 no.2
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• pp.487-496
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• 2008

The purpose of this study is to investigate clinical frequency and priority of five pattern identification settled by Korean Standard Differentiation of the Symptoms and Sign for Stroke. The present study was done over 177 hospitalized patient with stroke in the Daejeon University Oriental Medical Hospital in the period of November 2006 to July 2007. Stroke patients had been interviewed by residents and specialists who studied standard operation procedures in Fundamental study for Standardization and Objectification of Differentiation and Pattern Identification of Syndrome of Oriental Medicine for Stroke. In Heat-transformation pattern group, men showed significantly high frequency and in Deficiency of Gi pattern group, women showed significantly high frequency. In Heat-transformation pattern group, the indicators such as 'aversion to heat during fever', 'flushed face', 'full and rapid pulse', 'dryness of the eyes, 'yellow coating of the tongue', 'feverishness of the limbs', 'dryness of the eyes' showed significantly high frequency. In Dampphlegm syndrome group, the indicators such as 'white coating of the tongue', 'yellowish face', 'thick coating of the tongue', 'wheezing in the throat with sputum', 'swollen tongue', 'slippery pulse' showed significantly high frequency. In Deficiency of Gi pattern group, the indicators such as 'pale tongue', 'lassitude', 'pale face', 'weakness pulse' showed significantly high frequency. In Deficiency of Eum group, the indicators such as 'short and rapid pulse', 'mirror-like tongue' showed significantly high frequency. For more sensitive Korean Standard Differentiation of the Symptoms and Signs for Stroke, Large scale study is to be done, giving weight on the important indicators.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.14 no.1
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• pp.15-22
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• 2008

The excitement over radio frequency identification (RFID) technology has gained momentum in the last five years, with a diversification in the range of applications. Besides academic research into radio frequency identification (RFID) has proliferated over the last few years, however there is much to be desired on Packaging industry. In this paper, we present a literature reviews of researches of RFID system on Packaging, especially focused on RFID system standardization into packaging. There is not any packaging standard or guidance about tag locations, classification with the materials and so on. Therefore it hampers reduction of the distribution costs on political and corporate sides, and lack consistency of applying RFID system. The main focus of this review paper is to establish a constituency about legislating RFID system standard on packaging. It is hoped that the review will be a good resource for future research in order to applly RFID system to Packaging industry effectively.

• Annals of Clinical Neurophysiology
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• v.16 no.2
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• pp.49-54
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• 2014

Heart rate variability is significantly associated with cardiovascular complications in various neurological disorders with cardiac impairment. Measures of spontaneous heart rate variability might be different from provocating tests of heart rate variability such as deep breathing and Valsava maneuver. Methods for analysis are divided into time domain methods and frequency domain methods. There are standard deviation of NN interval, standard deviation of average NN interval, root mean square of the successive differences, NN50, and pNN50 in time domain methods. Frequency domain bands can be divided into very low, low, and high frequency. Each variables are influenced by sympathetic and/or parasympathetic activity.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.62 no.1
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• pp.70-75
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• 2013

The electrical separation joint as a filter circuit distributes the track circuit frequency. The electrical separation joint is classified into the interval where reinforcing bars are insulated and not insulated through the length of track circuit. In case of incorrectly setting up the length of electrical separation joint, the amplitude of current on the track circuit is not over standard current which is the standard of current on the track circuit and it effects on the close frequency on track circuit. Then, it makes an accident or makes a train not receive information for train control. In this paper, the electrical separation joint model is suggested and parameters are numerically calculated in the model. Moreover, the length of electrical separation joint is analyzed and is demonstrated by uisng Matlab and PSpice program.

• Proceedings of the KIPE Conference
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• 1999.07a
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• pp.367-372
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• 1999

In this paper, an inverter fed induction motor drive system is analyed in order to predict the conducted interference. High frequency model for inverter, motor and system parasitic components are proposed. High frequency component allows time and frequency domain analysis to be performed with standard PSpice tool. The overall high frequency component and model are verified by comparing simulation and experimental result.