• The Korean Journal of Applied Statistics
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• v.28 no.5
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• pp.1003-1011
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• 2015

We studied indices to explain runs lost for Korean professional baseball teams. Kim and Kim (2014) studied batting indices to explain run productivity of teams; subsequently, we studied fielding indices to explain runs lost. We considered several combined indices made by combining fielding indices closely connected with the runs lost of teams. Data analysis from all games in the regular seasons of 1982~2014 show that weighted WPH (defined as weighted average of WHIP and number of home runs allowed per game) best explain runs lost. Weighted WPH consisting of WHIP (with weight 81%) and number of home runs allowed per game (with weight 19%) was found optimal weighted WPH having correlation coefficient 0.95033 with average runs lost per game. Analysis by chronological periods gave results not much different.

• Journal of Convergence for Information Technology
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• v.8 no.6
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• pp.135-142
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• 2018

In recent years, researches utilizing UAV for military purposes such as precision tracking and batting have been actively conducted. In order to track the preceding flight, there has been a previous research on estimating the attitude information of the flight such as roll, pitch, and yaw using images taken from the rear UAV. In this study, we propose a method to estimate the attitude information more precisely by applying the Kalman filter to the existing image processing technique. By applying the Kalman filter to the estimated attitude data using image processing, we could reduce the estimation error of the attitude angle significantly. Through the simulation experiments, it was confirmed that the estimation using the Kalman filter can estimate the posture information of the aircraft more accurately.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.6
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• pp.239-244
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• 2019

The purpose of this study was to determine the correlation between upper limb muscle power and bat swing speed in elementary school baseball players. This study subjects were 32 subjects. Upper extremity muscle strength was measured in the Both Shoulder joints extensor flexor abductor adductor, Both elbow joints extensor flexor and bat swing speed. The correlation between upper extremity muscle strength and bat swing speed was analyzed using pearson's correlation analysis. There was a significant correlation between dominant upper extremity muscle strength and bat swing speed in the order of shoulder adductor, shoulder abductor, elbow flexor, and shoulder flexor and in correlation between non-dominant upper extremity muscle strength and bat swing speed in the order of shoulder adductor, elbow flexor, shoulder abductor, shoulder extensor, elbow extensor, and shoulder flexor. From these results, it can be seen that the stronger the upper extremity muscle strength, the bat swing speed is the more positive correlation.

• Journal of the Korea Convergence Society
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• v.12 no.8
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• pp.61-66
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• 2021

The purpose of this study was to investigate the relationship between vertical jump and lower extremity muscle strength of elementary school baseball players. This study subjects were conducted with a total of 40 subjects. Vertical jump was measured using a vertical jump gauge, and a hand held dynamometer was used to measure lower extremity muscle strength. For the measurement of lower extremity muscle strength, flexion·extension·adduction·abduction·internal rotaiton·external rotation of both hip joint, flexion·extension of both knee joint, dorsi flexion·plantar flexion of both ankle joint were measured. pearson's correlation analysis was used to analyze the correlation between vertical jump and lower extremity muscle strength. From these results, it was found that the stronger the leg muscles except for the plantar flexion, the higher the vertical jump was, indicating a positive correlation. In future studies, follow-up studies on the relationship between batting ability and vertical jump & lower extremity muscle strength are needed.

• Women's Health Nursing
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• v.2 no.1
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• pp.106-124
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• 1996

This paper reviews battering, sexual violence and divorce experienced among women. There three problems have negative influence on health status in women and are further developed to social problems such as family dissolution. The victims of the problems may manifest physical injury, emotional difficulties and social withdrawl, while their children may show problems caused by lack of parental caring and by resembling abusive behaviors of their parents. Hence, nurses need to pay attention to batting, sexual violence, and divorce and to develop relevant nursing interventions for them. Some strategies of dealing with those problems are presented in the following. First, we have to eliminate sexism prevailing in out society. Our society is assigning inequal and asymmetrical gender role. Mass media should inspire equality between genders and show a healthy model of family and community. Second, social system and laws should be changed through collective efforts. Those living conditions of women cannot be changed by the effort of women themselves only. We all need to work for establishing and changing the law, so that those women in suffering can obtain immediate and adequate protection. Third, social support system of consulting and referring women's problems should be established. Such support system as hot line, shelter and counseling clinics would help women in crisis. Fourth, job training and arrangement should be available to women who are divorced. Fifth, there should be self-help group for those women in suffering. Self-help group would help those women in sharing their problems and feelings and in establishing coping strategies. Nurses, as the largest group among health professionals, are sensitive and respond to health needs of clients and have an effect on managing women's health. However, we nurses have not been ready for dealing with problems of women, although most of us are women. we not need to change our perspective of women's health problems from a traditional medical perspective to feministic one. Accordingly, nurses need to develop realistic way of caring those women in suffering and to assist them in making decisions for their lives by themselves.

• Journal of the Korean Wood Science and Technology
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• v.43 no.6
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• pp.777-783
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• 2015

Wood is an anisotropic material that shows the changes in hardness, quality and dimensions depending on the types of cells on three cross sections, size, array and so on. It can also be used in different ways according to its use, which requires a meticulous research, in order to maximize the utilization by understanding the nature and use; and by clarifying the theory and technologies. The research on relationship among wood's physical properties, density, and elasticity of modulus have been studied in Korea and abroad, but those studies were based on correlation gained through standardized specimen. Rather, the study on complete product is rare. Moreover, the previous reports are mostly concentrating on vibration mode and batting, though the wood's physical properties as a material have not been in the main focus. Therefore, this study will carried out for analyzing MOE through figuring material property out and comparing frequency adapting to the Canadian HardMaple bat. For comparison of material properties, we studied the annual ring and density of the bat; calculated the MOE with resonance frequency and formula (ASTM C1259); and verified the repulsive force of this material. As a result, the relevance of the resonance frequency and annual ring is weak, and in comparison in the grain direction in wood, the MOE value is higher when the grain direction in wood is excited horizontally than when is excited vertically, because the material is repulsive when grain direction is horizontal.

• Journal of the Korean Society of Clothing and Textiles
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• v.16 no.2
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• pp.245-254
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• 1992

The purpose of this study was to evaluate the mechanical thermal resistances and comfort properties of ski wear made with vapor-permeable water repellent (VPWR) fabrics and thermal insulation battings. Four types of experimental clothing were made with the combination of two VPWR fabrics (Hipora-$TM^{\circledR}$, Hipora-$CR^{\circledR}$) and two thermal insulation battings ($Viwarm^{\circledR},\;Airseal^{\circledR}$). Thermal resistances of ski wear were objectly evaluated by thermal manikin experiment ($21{\pm}\;2^{\circ}C,\;50{\pm}5\%$ R.H.,0.25 m/sec air velocity) and thermographic accessment ($2{\pm}2^{\circ}C,\;0\%$ R.H.,0.25 m/sec air velocity, and emissivity level : 1). Garment wear tests of ski wear included the measurement of the microclimate (inner temp. and relative humidity) of the experimental clothing by digital thermohygrometer and subject wear sensation using McNall's thermal comfort ratings. CBo values of experimental clothing 4 (Hipora-$CR^{\circledR}+Airseal^{\circledR}$) and 1 (Hipora-$TM^{\circledR}+Viwarm^{\circledR}$) were significantly higher than those of 2 (Hipora-$TM^{\circledR}+Airseal^{\circledR}$) and 3 (Hipora-$CR^{\circledR}+Viwarm^{\circledR}$). Thermal resistances in the points of breast, back, belly, and loin was significantly higher than those of upper am, fore arm, and shank of measuring points on the thermal manikin. According to the color map of the thermogram, the experimental clothing 4 indicated higher surface temperatures than the others showing more yellowish spots on the surface of clothing. Inner temperature of experimental clothing was not significantly different among the four types of ski wear, but relative humidities of experimental clothing were significantly different. Relative humidities of experimental clothing 1 and 3 showed higher than those of 2 and 4. Relative humidity of experimantal clothing was affected largely by the thermal resis- tance of thermal insulation batting materials. The subject wear sensation of experimental clothing 2 and 4 showed lower humidity than the others. Subject wear sensation was affected more by humidity sensation than by thermal sensation.

• Korean Journal of Applied Biomechanics
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• v.23 no.1
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• pp.25-35
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• 2013

This study examined 24 right-handed amateur baseball players. Twelve who had played baseball for more than 6 years were grouped as skilled players, while 12 who had played for 1-3 years were the unskilled player group. The swing motion was divided into four event phases: stance, backswing, impact, and follow-through. The mean and maximum plantar pressure, center of pressure, and ground reaction force were measured during each event phase. The mean and standard deviations for each variables were calculated and differences were validated with the independent sample t-test. A p-value <0.05 was considered statistically significant. The results were as follows. 1)The ideal stance is a stable, balanced position with more than 65% of weight on the right foot. There was significant difference in mean left plantar pressure, while the maximal plantar pressure and mean right plantar pressure did not differ significant. 2)The effective backswing of a skilled player is comprised a rightward shift in weight to build maximum energy. More than 90% of the weight was on the right foot. There was a significant difference in the mean left plantar pressure, while the maximal plantar pressure and mean right plantar pressure did not differ significantly. 3) For an effective impact, a rapid shift in weight to the left foot is essential, so that a power hit is obtained. Significant difference in the mean and maximum plantar pressures of both feet were observed. 4)Follow-through requires wight balance, more on the right than the left, without leaning leftward. There was no significant difference in the mean or maximum plantar pressure. 5)The center of plantar pressure should move from the center of the foot to the toe. 6)The analyses of the ground reaction force suggest that a good swing involves a gradual shift in weight to the right side and a rapid leftward shift at impact. Good balance, with the center of gravity on the right side at follow-through, is also required.