• Nuclear Engineering and Technology
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• v.53 no.11
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• pp.3517-3527
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• 2021

New 80-MW (electric) ultra-long-life sodium cooled fast reactor core having inherent safety characteristics is designed with heterogeneous fuel assemblies comprised of driver and blanket fuel rods. Several options using upper sodium plenum and SSFZ (Special Sodium Flowing Zone) for reducing sodium void reactivity are neutronically analyzed in this core concept in order to improve the inherent safety of the core. The SSFZ allowing the coolant flow from the peripheral fuel assemblies increases the neutron leakage under coolant expansion or voiding. The Monte Carlo calculations were used to design the cores and analyze their physics characteristics with heterogeneous models. The results of the design and analyses show that the final core design option has a small burnup reactivity swing of 618 pcm over ~54 EFPYs cycle length and a very small sodium void worth of ~35pcm at EOC (End of Cycle), which leads to the satisfaction of all the conditions for inherent safety with large margin based on the quasi-static reactivity balance analysis under ATWS (Anticipated Transient Without Scram).

• Proceedings of the IEEK Conference
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• 1999.11a
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• pp.1163-1166
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• 1999

In this paper, A CMOS power amplifier for PCS is designed with 0.65-$\mu\textrm{m}$ CMOS technology. Differential cascode structure is used which has good reverse isolation and wide voltage swing. This amplifier circuits consist of three stages which are power amplification stage, driver stage and power control stage. We obtain output power of 30 ㏈m, IMD3 of -31㏈c and efficiency of 30 % at input power of 4 ㏈m.

• Korean Journal of Applied Biomechanics
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• v.19 no.2
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• pp.323-336
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• 2009

The purpose of the current study was to research scientific basis and necessity of supplementary materials for field lesson out of golf swing teaching methods. As the subject of study, skillful tour pro golfers were chosen to reinterpret field lesson results for driver swing from the viewpoint of kinematics. In addition, through precise analysis, this study developed a case to verify the validity and error of field lesson. As a result, field lesson showed a slight difference among qualitative evaluation of kinematical analysis of techniques, subjects of study, and items. Accordingly, there was a little difference between two methods in view of evaluation of errors that 5 subjects of the study have shown. However, there was a significant difference in compensation to prevent causes of error and errors. Based on instructor's experience most errors could be evaluated. Therefore, feedback for error correction based on instructor's experience showed a significant difference from qualitative evaluation of kinematical analysis of techniques. In conclusion, the following are required for correct golf swing lesson; instant feedback through field lesson and qualitative evaluation of kinematical analysis of techniques to determine fundamental causes correctly.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.10 no.3
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• pp.25-35
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• 2011

Traffic volume increases due to diversification of industry. Also, Automobile ownerships also increase steadily. It is estimated that the registered number of vehicle is expected to be 20 milion in the year 2015. These trends may result in increasing the number of woman drivers and elderly drivers. Therefore, this study aims to identify routes that reflect characteristics of each driver's preferences. A survey was conducted on different routes attributes for variances drivers. Driver types were classified by gender, age, and driving career. Accordingly, a weight for road composition attribute such as number of lanes, number of accidents, slope was estimated by using Swing Weighting technique in Multi-Attribute Utility Theory. In addition, a case study was conducted and identified weights were applied to routes. In result, drivers commonly prefer short route when they considered their routes. Also, male drivers prefer speedy and shorter route than that of female drivers. Elderly drivers prefer safe routes that represent low accidents rate. Moreover driving career under a year drivers prefer safe and easy routes. Therefore, we may conclude that the necessity of diversified route information is essential in the future car navigation system.

• Journal of the Korean Applied Science and Technology
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• v.35 no.1
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• pp.273-283
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• 2018

The purpose of this study is to analyze the optimum driver selection according to shaft intensity, shaft length and shaft weight that are determining factors of driver shot. To achieve the above purpose, the subject were participate with handicap zero 10 male pro golfer and mean score 90(handicap about 18) amateur 10 male golfer. The used club limited number 1 driver, we tested 24 driver which is shaft intensity, length, weight, total weight and swing weight. Dependent variable was strike ball speed, flying distance and head speed. The findings can be summarized as follows. First, There is a significantly difference in CPM. Ball speed, head speed and flying distance according to driver shaft intensity were found to be the best when CPM is 230<. Second, There is a significantly difference in shaft length. Ball speed, and head speed according to driver shaft length were found to be the best at 46 inch and flying distance were found to be the best at 45 inch. Third, There is not significantly difference in SW. Ball speed and flying distance according to driver shaft weight were found to be the best with 65g. In the case of head speed, it was the fastest with 50g shaft. Four, total variables were significantly difference between in pro and amateur golfer. In conclusion, there would be differences in individual physical condition but the best result was found with a driver of CPM 230<, shaft length 46inch, and shaft weight 65g.

• Korean Journal of Applied Biomechanics
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• v.15 no.3
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• pp.71-78
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• 2005

The purpose of this research was to conduct an analysis on the factors that determine the distance at the time of target swing based on the use of late hitting of outstanding college golfers to verify the difference between late hitting and the distance that target increases in regular swing and the distance. Then, this research conducts an analysis on the correlation between club head velocity, ball velocity, launch angle, back spin, meet ratio and distance that become kinematics variables at the time of target swing. To attain the above mentioned purpose, 25 outstanding college players with average experience and handicap of 6 years and 5, respectively, were targeted Comparative analysis on two swing that target increase in regular and the distance was conducted by used driver. When it pertained to two types of swing. analysis system comprised of an analytical software called the Science Eye of the Bridgestone and peripheries was used to define the relationship between variables of club head velocity, ball velocity, launch angle, back spin, meet ratio that become kinematics variables. As for the method of processing data pertaining to the factors that determine the distance, differences of distance by the type of swing was verified by using independent T-test that leveraged SPSS 120 statistics program. Moreover, level of correlation between variables that contribute to the increase in distance through relation of correlation, and analysis of tendencies was conducted to analyze tendency of non-distance to increase in accordance to the increase of each variable. Key results produced through this experiment are as follows: 1. Artificial late hitting for increased non-distance that targets skilled players had effect on increased the distance(p<. 05). 2 The drive distance is correlated with each measured variable that is positive correlation to ball velocity, club head velocity, meet ratio and relation of back spin and launch angle are negative correlation. ball velocity and club head velocity are very high correlated with drive distance(p<.01), back spin and distance are negative correlation(p<.01). 3. Among each measured variable increasing the club velocity is the most contribution, and ball velocity and meet ratio and the increasing launch angle and back spin is negative effect for increasing distance.

• Physical Therapy Rehabilitation Science
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• v.6 no.4
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• pp.189-195
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• 2017

Objective: The purpose of this study was to examine the effects of real-time visual feedback weight shift training during golf swinging on golf performance. Design: Repeated-measures crossover design. Methods: Twenty-sixth amateur golfers were enrolled and randomly divided into two groups: The golf swing training with real-time feedback on weight shift (experimental group) swing training on the Wii balance board (WBB) by viewing the center of pressure (COP) trajectory on the WBB. All participants were assigned to the experimental group and the control group. The general golf swing training group (control group) performed on the ground. The golf performance was measured using a high-speed 3-dimensional camera sensor which analyses the shot distance, ball velocity, vertical launch angle, horizontal launch angle, back spin velocity and side spin velocity. The COP trajectory was assessed during 10 practice sessions and the mean was used. The golf performance measurement was repeated three times and its mean value was used. The assessment and training were performed at 24-hour intervals. Results: After training sessions, the change in shot distance, ball velocity, and horizontal launch angle pre- and post-training were significantly different when using the driver and iron clubs in the experimental group (p<0.05). The interaction time${\times}$group and time${\times}$club were not significant for all variables. Conclusions: In this study, real-time feedback training using real-time feedback on weight shifting improves golf shot distance and accuracy, which will be effective in increasing golf performance. In addition, it can be used as an index for golf player ability.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.38 no.8
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• pp.54-61
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• 2001

A fully on-chip open-drain CMOS output driver was designed for high bandwidth DRAMs, such that its output voltage swing was insensitive to the variations of temperature and supply voltage. An auto refresh signal was used to update the contents of the current control register, which determined the transistors to be turned-on among the six binary-weighted transistors of an output driver. Because the auto refresh signal is available in DRAM chips, the output driver of this work does not require any external signals to update the current control register. During the time interval while the update is in progress, a negative feedback loop is formed to maintain the low level output voltage ($V_OL$) to be equal to the reference voltage ($V_{OL.ref}$) which is generated by a low-voltage bandgap reference circuit. Test results showed the successful operation at the data rate up to 1Gb/s. The worst-case variations of $V_{OL.ref}$ and $V_OL$ of the proposed output driver were measured to be 2.5% and 7.5% respectively within a temperature range of $20^{\circ}C$ to $90^{\circ}C$ and a supply voltage range of 2.25V to 2.75V, while the worst-case variation of $V_OL$ of the conventional output driver was measured to be 24% at the same temperature and supply voltage ranges.

• Korean Journal of Applied Biomechanics
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• v.17 no.2
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• pp.31-40
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• 2007

Proper weight shifting is essential for a successful shot in golf swing and this could be described by means of the ground forces between the feet and ground. It is assumed that the ground forces would different according to the club used because the length and swing weight of each club is different. But, in present, it is not clear what changes are made by the change of clubs and this affect the swing motion. Therefore this study focused on the investigation of the changes of the ground forces and ground reaction forces (GRF) by the change of club length. The subjects were three professional male golfers. Four swings (driver, iron 3, iron 5, and iron 7) for each subject were taken by two high speed video cameras and two AMTI force platforms were used to measure the GRF simultaneously. Kwon GRF 2.0 and Mathcad 13 software were used to post processing the data. Changes of the three major component of GRF (Vertical, lateral, anterior-posterior force) at 10 predefined events were analyzed including the maximum. Major findings of this study were as follows. 1. Vertical forces; - There were no significant changes until the top of backswing. - Maximum was occurred at the club horizontal position in the downswing for both feet. The shorter club produced more maximum forces than longer ones in the left foot, but reverse were true for the right foot. - Maximum forces at impact shows the same patterns. 2. Lateral forces; Maximum was occurred at the club horizontal position for both feet, but there were no lateral forces because the direction of two forces was different. Maximum force pattern by different clubs was same as the vertical component. 3. Anterior-posterior forces; - This component made a counter-clock wise moment about a vertical axis located between two foot until the club vertical position was reached during the backswing, and reverse moment were produced when the club reached horizontal at the downswing. - Also this component made a forward moment about a horizontal axis located in the CG during the fore half of the downswing, and a reverse moment until the club reached vertical at the follow through phase. Maximum was occurred at the club vertical in the downswing for both feet. The longer club produced more maximum forces than shorter ones for both feet.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.62 no.2
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• pp.84-89
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• 2013

In this paper, we propose interface circuits for reducing power consumption and EMI when sequences of data from LCD controller to LCD driver IC by transmitting two bit data during one clock period. The proposed circuits are operated in current mode, which is different from conventional voltage-mode signaling techniques, and also employ threshold technique of Modified-LVDS(Low Voltage Differential Signaling) method. We have simulated the proposed circuits using H-SPICE tool for performance analysis of the proposed method. The simulation results show that the proposed circuits provide a faster transmission speed and stronger noise immunity than the conventional LVDS circuits. It might be suitable for the real-time transmission of huge image data in LCD system.