• Journal of Ocean Engineering and Technology
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• v.9 no.1
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• pp.47-56
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• 1995

This study is aimed to have a database of system development for the prediction, monitoring, analyzing, and evaluation of tensile strength and damage characteristics through AE technique for CFRP. Therefore the correlations between impact characteristics (such as impact velocity, impact energy, delamination area etc) and AE signals for CFRP laminates were investigated. And also it were accomplished the evaluation of tensile strength and the investigation on correlation with AE signals for impact damaged specimen of CFRP laminates.

• Journal of Digital Convergence
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• v.16 no.9
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• pp.173-178
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• 2018

The vehicle collision speed in mid and high range can be checked by EDM(Event Driven memory) data recorded when the air bag works. But it's difficult to estimate the low speed of vehicle collision. And estimating the speed is important because the injury level can be changed by the impact speed. The study proposed an estimating algorithm by analysing the images recorded in car blackbox instrument. Low speed rear collision accidents simulated with wire winding motor for various vehicle types. The study estimated the impact speed with the ratio of the distance change between two vehicles and the length change of the number plate of front vehicle. The closer the vehicles are, the larger the plate length is. You can estimate the impact speed with the ratio. The impact speed is calculated with the initial distance for a specific length of number plate in the algorithm. The results can be applied to the linear rear collision because the angle of impact was not considered in this study.

• Korean Journal of Applied Biomechanics
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• v.24 no.1
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• pp.11-18
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• 2014

The purposes of this study were to analyze the kinematics and electromyographic variables of the upper extremity for the backhand clear motion according to the type of hitting in badminton. Seven elite male university players were selected as the subjects. Four digital video cameras and Noraxon Telemyo 2400 were used to collect the 3D kinematics and electromyographic data. The results were as follows: 1) in the phase of impact, the time of motion for the overhead backhand clear was the longest, 2) in the event of impact, the distance of step toward X direction was the longest and the distance of step toward Y direction was the shortest for the overhead backhand clear, 3) in the event of backswing, the rotation angles of shoulder and pelvis and the flexion angle of shoulder for the overhead backhand clear were the biggest, 4) the maximum flexion angular velocity of shoulder and the maximum extension angular velocity of elbow for the overhead backhand clear were the biggest, and 5) in the phase of impact, mean EMG of the wrist flexor, triceps, and trapezius muscle for the overhead backhand clear was bigger than that for the underhand stroke and in the phase of follow-through, mean EMG of the wrist flexor and extensor, biceps, triceps, and trapezius muscle for the overhead backhand clear was the biggest.

• The Journal of Asian Finance, Economics and Business
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• v.9 no.10
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• pp.137-145
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• 2022

This study aims to test the information content of sustainability reports issued by the most significant telecommunications companies operating in the Kingdom of Saudi Arabia (Stc, Zain, and Mobily), and their compatibility with the national sustainability standards issued by the Ministry of Commerce in the Kingdom of Saudi Arabia in light of the Kingdom's vision 2030, and its impact on the stock exchange indices of these companies. The event study methodology was used to study the impact of publishing sustainability reports on stock prices and the trading volume of these companies' shares in the Saudi stock market during the period from (October 2020 to March 2021). The results indicate a significant impact of the information contained in the sustainability reports on stock prices and trading volume in the stock market, and the importance of directing the company's management towards more disclosure of information about sustainability in its environmental, social, and economic aspects instead of focusing only on information related to the financial performance and economic activity of the company. This encourages the listed companies to disclose the sustainability of the financial reports and standardize the form in which these disclosures are prepared.

• Knowledge Management Research
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• v.13 no.5
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• pp.139-160
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• 2012

Win-win growth between large companies and small and medium enterprises (SMEs) become a critical encomic and social issue in Korea. Korea government has been attempted to establish strong policy to build right win-win relationship between large companies and SMEs. Along with this strong drive from Korea government, a variety of strategies that enhance win-win relationships between large companies and SMEs have been adopted. Win-win growth policy is expected to provide positive impact on sustainable competitive advantage of firms. Therefore, many studies have focused on the win-win growth policy success factors, type of the policy, and the results of the policy. Although there is much literature on the win-win growth policy, the effects of win-win policy on firm value is not well understood. We addressed this issue by exploring how win-win growth policy influences a firm's market value using event study methodology. We evaluated the cumulative abnormal returns for win-win growth policy announced by Korean large firms from 2004 to 2012. The results of this study insisted that the announcements of win-win growth policy show negative impact on firm's market value, which is not consistent with previous studies. The findings of this study offer insights that may help government policy makers and managers to revise their policy for better outcomes of their win-win growth policy.

• Asia-Pacific Journal of Business
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• v.13 no.4
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• pp.135-149
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• 2022

Purpose - The primary objective of this article is to investigate the impact of U.S. monetary policy on institutional / individual / foreign investor reactions in the Korean stock market. Design/methodology/approach - This study employs a high frequency event study methodology to identify U.S. monetary policy shocks and quantify the impact of identified shocks on investor reactions. The dependent variable in the regression model is net stock purchase, while the explanatory variables are U.S. monetary policy shocks. The model is estimated for the period 2000-2019, including 156 FOMC meetings. Findings - Foreign investors immediately sell stocks in response to contractionary U.S. monetary shocks. They do not, however, react to anticipated changes in monetary policy rates, confirming the rationality of foreign investors. Individual investors demonstrate the opposite response, indicating that a non-trivial proportion of individual investors are irrational. Research implications or Originality - This study adds to the current literature on the effect of U.S. monetary policy on the Korean stock market. This study demonstrates a heterogeneous response to U.S. monetary policy shocks, validating the rational investment behavior of foreign investors, while individual investors exhibit a certain degree of irrationality. Methodologically, this study adds to the literature by quantifying the impact of U.S. monetary policy employing a sharper identification method allowing a simple and consistent estimation.

• Korean Journal of Applied Biomechanics
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• v.13 no.1
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• pp.155-171
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• 2003

The purpose of this study was to analyze the kinematic variables of over head kick(OHK) in soccer with three dimensional analysis technique and show the kinematic characteristics of it. The 7 subjects were university football player who have been playing football more than 7 years. The OHK was filmed on 16mm video camera(30frame/sec.) kinematic variables were temporal, postures, and COG(center of gravity). The mean values and the standard deviation for each variables were obtained and used as basic factors for examining characteristics of OHK. The results of this analysis were as follows : Temporal variables : The total time elapsed(TE) of OHK was $0.95{\sim}1.14sec$, the 1st phase was 0.35sec., 2nd phase was 0.46sec., and 3rd phase was 0.22sec.. Posture variables : When subjects performed OHK at the impact event, the ankle and knee angle of kicking foot were more extend than supporting foot. but the hip angle of supporting foot were more extend than kirking foot. Moving distance of the center of mass of the both foot. When subject performed OHK at the impact event, the range of distance on mediolateral direction aspect into right left shoulder line, anteroposterior direction aspect was $20.9{\pm}10.5cm$, vertical direction aspect was $92.3{\pm}19.9cm$. Angular velocity : the faster angular velocity of knee ankle on the kicking foot pew form jump position to landing position, the faster velocity of ball became. C. O. G. variables. When subject performed OHK at the impact event, upper part of the body was getting lower, lower part of the body was getting higher.

• The Journal of the Korea Contents Association
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• v.10 no.11
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• pp.92-101
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• 2010

Many cities in the world are trying to enhance city awareness and city image through international events. In this study, the impact of 2008 Beijing Olympic Games on Beijing Image was investigated by survey. According to the result of data analysis, there is a positive correlation between the watching time of Beijing Olympic Games on TV in weekend and familiarity to Beijing. And there is a positive correlation between the watching time of Beijing Olympic Games on TV in weekend and attitude toward Beijing, too. Familiarity to Beijing and Beijing Olympic Games management have an significant impact on Beijing image, attitude toward Beijing and intention to visit Beijing. Familiarity to Beijing than Beijing Olympic Games management has a larger impact on Beijing image and attitude toward Beijing.

• The Journal of the Korea Contents Association
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• v.12 no.8
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• pp.399-410
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• 2012

This study is to investigate the expenditure patterns that was generated by visitors who attended The Korean Music Wave Festival and analyze economic impact derived from that event. The target is the foreign visitors who attended '2011 Incheon Korean Music Wave'. Total of 407 questionnaires were collected. The collected data were analyzed to produce spending patterns using Tobit models. Also, tourism multipliers were employed to identify the economic impact. This results show that expenditure determinants such as demographic variables and satisfaction as independent variables are significant in estimating visitors' expenditures. Also, In addition economic impact derived from direct spending was substantially over committed cost. Accordingly, this result can contribute to providing basic information for marketing strategy that generates the economic effect on the destination. Moreover, the result can be utilized when establishing the strategy that can maximize the economic impact based on the spending patterns.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.16 no.5 s.110
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• pp.503-513
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• 2006

The duration time of aircraft noise event is also an important factor for the evaluation of civil aircraft noise, which is considered as a notable characteristic of military aircraft noise. SEL is proved as a suitable noise metric for the measuring military aircraft noise of various flight pattern considering the duration time of noise event. This study reviews whether SEL is a suitable for measuring civil aircraft noise and study shows SEL is fairly compensating the duration time of civil aircraft noise event for the evaluation of aircraft noise. Noise metric for the evaluation aircraft noise based on SEL is more appropriate than based on $L_{MAX}$ for compensating duration time of noise event either military aircraft or civil aircraft. In this reason, current formula of WECPNL based on energy average of measured $L_{MAX}$ for the evaluation of aircraft noise impact in 'Test Method of Noise and Vibration of Korea' is recommended to be amended to formula of WECPNL based on energy average of measured SEL considering compensation of noise event duration time, if WECPNL is not based on measured EPNL, a metric compensating duration time.