• 한국해양공학회지
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• 제9권1호
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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.

• 디지털융복합연구
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• 제16권9호
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• pp.173-178
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• 2018

에어백이 작동되는 중고속 추돌 사고의 경우 에어백 작동 전후의 차량 데이터가 차량의 EDM(Event Driven Memory)에 저장되어 그 추돌 속도를 쉽게 알 수 있다. 하지만 에어백이 작동하지 않는 저속영역에서 추돌하는 경우 그 속도를 산정하기가 어렵다. 또한 저속이라 하더라도 추돌속도에 따라 운전자의 부상 정도가 크게 영향을 받기 때문에 그 속도의 산정이 중요하다. 본 연구에서는 블랙박스에 저장된 영상 이미지를 분석하여 저속영역의 추돌속도를 연산하는 알고리즘을 제안하였다. 전기모터로 와이어로프를 이용하여 차량을 견인하는 방식으로 저속의 후방추돌 상황을 정확하게 재현하면서 다양한 차종과 속도에 대해 실험을 수행하였다. 이 때 블랙박스의 영상 이미지에서 두 차량의 거리가 좁아지는 비율과 전방 차량의 번호판 길이가 증가하는 비율이 동일함을 이용하여 추돌속도를 정밀하게 계산할 수 있다. 즉, 미리 측정된 초기거리와 블랙박스의 영상에서의 번호판의 길이를 초기조건으로 설정하여 본 연구의 계산 알고리즘을 적용하면 저속 추돌 속도를 정확하게 산정할 수 있다. 직선 추돌사고에는 본 연구의 결과가 그대로 적용되지만 각도를 두고 추돌하는 경우에는 별도의 고려가 필요하다.

• 한국운동역학회지
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• 제24권1호
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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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• 제9권10호
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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.

• 지식경영연구
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• 제13권5호
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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.

• 아태비즈니스연구
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• 제13권4호
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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.

• 한국콘텐츠학회논문지
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• 제10권11호
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• pp.92-101
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• 2010

세계의 많은 도시들은 국제 행사의 개최를 통해 각 도시의 인지도와 이미지를 제고하려는 노력을 기울이고 있다. 본 연구에서는 대형 스포츠 이벤트인 2008 베이징 올림픽이 베이징 이미지에 미치는 영향에 대해 부산시민 197명에 대한 설문조사를 실시하여 살펴보았다. 수집된 자료의 분석 결과, 주말의 베이징올림픽 시청시간은 베이징에 대한 친밀감, 베이징에 대한 태도와 정적인 상관관계를 갖는 것으로 나타났다. 베이징에 대한 친밀감과 베이징 올림픽 게임 운영에 대한 평가는 베이징에 대한 이미지, 베이징에 대한 태도, 베이징에 대한 방문의도에 유의미한 영향을 미치고, 그 중에서 베이징에 대한 친밀감이 더욱 큰 영향을 미치는 것으로 나타났다.

• 한국운동역학회지
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• 제13권1호
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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.

• 한국콘텐츠학회논문지
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• 제12권8호
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• pp.399-410
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• 2012

본 연구의 목적은 한류관광의 대표적인 스페셜이벤트인 인천한류관광콘서트에 대한 외래관광객의 소비 지출 패턴을 규명하고 그로인해 창출되는 경제적 파급효과를 분석하는 것이다. 자료는 2011년 인천한류관광콘서트에 관람한 외래관광객을 대상으로 설문조사를 실시하였다. 지출의 패턴은 토빗모형을 설정하여 분석 하였으며, 경제적 파급효과는 인천지역의 관광유발계수를 적용하여 산출하였다. 분석결과, 인구통계적 특성, 국적, 만족도 등 지출에 영향을 미치는 결정요인들은 선택된 지출 항목별로 다양하게 표출되었으며 경제적 파급효과는 투입된 비용보다 상회하는 효과를 나타내고 있다. 따라서 지출패턴에 따라 한류관광콘서트에 대한 경제적 파급효과를 극대화 시킬 수 있는 전략을 수립하는데 중요한 기초자료가 될 수 있을 것이다.

• 한국소음진동공학회논문집
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• 제16권5호
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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.