• Journal of Magnetics
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• 제20권4호
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• pp.439-443
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• 2015

A control rod drive mechanism (CRDM) is an electromechanical equipment that provides linear movement for the control rods to control the nuclear reactivity in a nuclear reactor. A rod position indication system (RPIS) detects the control rod's position. To enhance the measurement accuracy of the system, a magnetostrictive type sensor with capability of generating operation limiting signals would be adapted instead of a conventional RPIS for a CRDM. An RPIS was modelled for a numerical analysis with the permanent magnets at the stationary limit positions and magnetic shielding plates with a moving permanent magnet. The performance analysis of the RPIS were conducted, and the results were discussed here.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1997년도 추계학술대회 논문집 학회본부
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• pp.38-41
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• 1997

As the LPM is used for position accuracy decision device it is required that both the reason of posion error and the definition of position itself should be cleared. In this study, the precision of the position decision of LPM is affected by the geometrical shape such as tooth shape or processing accuracy. By using the analysis of magnetic circuit, we calculated the permeance come up with the gap. Once the thrust force has been obtained, the permeance due to the mechanical error of the pole pitch and the tooth pitch becomes the error of thrust force. We confirmed as well that it is being affected by the difference due to the variation of the airgap permeance.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2004년도 추계학술대회 논문집
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• pp.606-610
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• 2004

In this paper, we would like to explain about the structure analysis of wheel set as variation of contact position between wheel and rail. Measurement of interacted force between wheel and rail is necessary for running safety evaluation as important factor of derailment mechanism. It's necessary to running safety evaluation of rolling stock. Wheel unload and lateral force change as variation of contact position between wheel and rail. Interacted force between wheel and rail got as each contact position through computer simulation. This is necessary process as first research for evaluation of derailment phenomenon and running safety.

• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2002년도 춘계 학술대회논문집
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• pp.164-170
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• 2002

Numerical analysis of the flowfield around a 50-meter class airship is performed to determine the optimal position for the airspeed probe installation. The turbulent flow around the hull with gondola is analyzed to examine the characteristics of the data measured by the probe attached to the gondola, and they turned out to show the nonlinear relation between the freestream and measured angles of attack and be influenced by the Reynolds number. New position of the hull nose was proposed and the effect of various factors on the flowfield around the nose was also examined. The analysis with a panel method showed that the effect of empennage was negligible, and the effect of gondola and boundary layer thickness had also little impact. It was shown that the freestream angle of attack would be the only independent variable for the probe position around the hull nose in constructing the calibration matrix.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 제36회 하계학술대회 논문집 B
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• pp.1153-1155
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• 2005

This paper deals with dynamic characteristics of LSRM according to drive condition. First, in experiment of LSRM, position of LSRM detected approximation sensor. Position choose mover of LSRM and inductance. When approved current in each phase by decided position, we made sure current and voltage according to turn-on, turn-off. Second, in dynamic characteristic of LSRM, through an experiment, we decided turn-on position of inductance profile. Also, we presented dynamic characteristic analysis model which is consisted at motor and sensor signal part, etc., and substitute circuit constant that get using magnetic equivalent circuit method, we confirmed current and voltage waveform.

• 동력기계공학회지
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• 제10권4호
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• pp.43-49
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• 2006

Nowadays, the thermal environments of classrooms are usually adjusted by the ceiling type air-conditioning system with a temperature sensor installed on inlet of an air-conditioner. However, it is not clear that the conventional temperature sensor position is proper to satisfy both thermal comport and energy saving in summer especially. Therefore, this study is aimed at finding out the best position of the temperature sensor on the purpose of the comfort thermal environment and energy saving. The different 5 positions for the temperature sensor are supposed in this paper to analyze thermal environment by CFD. From the analysis through the CFD simulations, the best position of the temperature sensor satisfying for both comfort thermal environment and energy saving is obtained.

• 소성∙가공
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• 제13권7호
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• pp.594-599
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• 2004

In the sheet metal forming operations, the strain measurement of sheet panel is an essential work which provides the formability information needed in die design, process design, and product inspection. To measure efficiently complex geometry strains, the 3-dimensional automative strain measurement system, which theoretically has a high accuracy but practically has about 3～5％ strain error, is often used. For eliminating the strain error resulted in measuring the strains of formed panels using an automated strain measurement system, the position error calibration method is suggested, which computes accurate strains using the grids with accurate nodal coordinates. The accurate nodal coordinates are calculated by adding the nodal coordinates measured by the measurement system and the position error found using the multiple regression method as a function of the main error parameters obtained from the analysis of strain error in a standard cube. For the verification, the strain distributions of square and dome cups obtained from the position error calibration method are compared with those provided by the finite element analysis and ASAME.

• 대한간호학회지
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• 제5권1호
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• pp.133-143
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• 1975

Most of mothers place their babies in either supine or prone position without change of position. Studies comparing supine and prone position of the newborn infants -have already been performed with the result that the prone position is relatively better than the supine position. However, one kind of position recommended to the mothers is not sufficient for the good rearing practice of children, because the same position placed for period long of time may bring out physical, mental tension and fatigue, and deformities of the skull and the thorax. For this reason nurses have to find out other position which has identical or more advantages than prone position so as to perform the position change for the babies. Main purpose of this study is to identify the differences of vital signs, the number of urination, defecation, diaper rash, crying and amount of feeding of the newborn infants with prone position or lateral position during the first three days of life. Sixty two newborn infants who were delivered at Seoul National University Hospital during the period from July 1 to September 5, 1974 were chosen as subjects for this study. The criteria for the choice of subjects were the babies born with vaginal delivery; body weight 2.5kg or over at birth; Apgar score Seven or over; and gestation period between thirty-eight months ana forty- two months. Of these subjects, by random sampling, thirty-one newborn infants were placed in the prone position and the other thirty-one in the lateral position. The results of this study reviewed in a statistical analysis of the t-test to obtain the following findings : 1. The heart rates of babies in the prone position were the mean heart rates of 135.03 and those in the lateral position 135.98 without any statistically significant difference. 2. There was no significant difference of respiration rate between two groups : a group in the prone position showed the mean respiration rates of 45,57 and the other in the lateral position 46.49. 3. There was no significant difference of body temperature between two groups: the mean body temperature of a group placed in the prone position was 98$^{\circ}$18'F(36$^{\circ}$77'C) and that of the other group 98$^{\circ}$20'F(36$^{\circ}$78'C). 4. One baby showed diaper rash only in a group of infants in the prone position. 5. The number of crying of the babies in the prone position were 23.70 and those in the lateral position 30.00 with a statistical difference at 5 percent level. 6, There was no difference of frequency of urination between two groups: the mean frequency of a group placed in tile prone position was 5.44 and that of the other group 5.06, 7. There was no significant difference of frequency of defecation between two groups : the mean frequency of a group placed in the prone position was 4.20 and that of tile other group 4.21, 8. There was no significant difference of feeding amount between two groups : the average amount of a group in the prone position showed 325.03 and that of the other group in the lateral position 291.51. All the above results mean that we may substitute tile lateral position for the Prone position or utilize both position for tile rearing practice of the babies.

• 한국ITS학회:학술대회논문집
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• 한국ITS학회 2008년도 제7회 추계학술대회 및 정기총회
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• pp.351-354
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• 2008

• 수산해양기술연구
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• 제54권2호
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• pp.181-187
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• 2018

In order for the probe to perform ocean exploration and survey research, it is necessary to adjust the position of the ship as desired by dynamic positioning system. The dynamic positioning system of T/S NARA is applied to K-POS dynamic positioning system of Kongsberg, which makes maintaining the ship's position, changing position and heading control possible. T/S NARA is not capable of dynamic positioning if one or more propulsive forces are lost with DP Level One. However, it is predicted that dynamic positioning can be achieved even at the time of missing one thrust in a good sea condition. Therefore, we want to analyze the effect of each propulsion on the performance of dynamic position system. When one of the bow thruster and azimuth thrusters lost their propulsion, maintaining the ship's position, changing position and heading control performance were compared and analyzed. If the situation occurred disable from using the bow thruster, they can not maintain ship's position. Azimuth thruster was influential for the ship's position control and bow thruster was influential in heading control. The excellent dynamic positioning performance can be achieved, considering the propulsion power that will have a impact on each situation in the future.