Purpose: This study aimed to make an in-depth analysis of various reasons that gymnasts quitted gymnastics, prevent them from quitting gymnastics and provide basic data and information for the activation of gymnastics. Methods: Open-ended interview questions about ‘Gymnasts’ hard points’ and ‘circumstances which made them to want to quit gymnastics’ were used for two coaches, three active players, junior high school students and above and two players who had already quitted gymnastics. The conceptual structure of quitting was analyzed for 1,022 male and female gymnasts, junior high school students and above, registered on Korea Gymnastic Association in 2013 through experts’ conferences. Results: It was shown that gymnasts mainly quitted gymnastics due to several factors such as the risk of injury, authoritative guidance, hard training, unstable future, poor motivation, poor acting abilities (skills) and a lack of studies. Conclusion: The following measures should be taken to prevent gymnasts from quitting gymnastics: the control of training intensity, a guarantee of the right to learn, player-personalized guidance, the creation of a positive training atmosphere, adequate rest, the understanding of players’ difficulties through on-going counseling and observation, coaches’ efforts to develop players’ potential talents and institutional support to prevent players from quitting gymnastics.

서울지역 28개 지하구조물에 대한 정밀안전진단 결과를 활용하여 제안된 균열집중구간 및 탄산화 기반 한계상태함수를 산정하여 우선적인 보수구간을 선별하고자 하였다. 상태평가를 위해 분할된 503개 쉬트에 대한 균열밀도는 로그정규분포, 탄산화 및 피복은 정규분포의 현장조사 결과를 얻었다. 각 구간별 실시한 강도, 초음파속도, CO2농도, 철근부식도, 염화물함유량 등을 고려할 수 있도록 환경지수를 도입하여 합리적인 보수 우선순위를 제안하고자 하였다.

Displacement is one of the most fundamental responses, containing useful information regarding dynamic behavior of a structure. Traditional displacement measurement devices such as LVDT have disadvantages in their high cost and few options on installation locations. For the sake of economic reason, vision-based displacement measurement systems using low cost cameras have been developed, yet these systems still have difficulties in finding appropriate camera positions; camera should be placed perpendicular to targets. This study presents a new vision-based displacement measurement system using the planar homography method that results in accurate displacement measurement, allowing the camera to face targets with an arbitrary angles. The proposed vision-based system was experimentally validated from a laboratory test.

In this study, a noncontact NDT method is implemented to detect the damage of pipeline structures and to identify the location of the damage. To achieve this foal, an Nd:YAG pulsd laser system is used to generate guided waves and a galvanometer-based laser scanner scans a specific area to find damage location. Then, a piezoelectric sensor is installed to measure structural responses. The measured time and spatial responses are transformed to data in frequency and wavenumber domain through 3-dimensional Fourier transform. Finally, damages can be detected by extracting reflected signals due to damage using wavenumber filter which eliminated strong incident waves.

The aim of this study is to experimentally verify the feasibility of the vibration control system to be implemented on 1/10 scale down floating structure with rigid body motion and propose a control algorithm to effectively control the dynamic responses of a floating structure. For this, active mass damper system was constructed and evaluated the function of each component consisting of the mass damper system.

In this paper, the filed test procedure for evaluating the performance of track structure for additional Speed-Up test on Test-Bed Section(KP 100∼128km Osong starting point). The behavior of track system corresponding the speed up of train will be identified by the analysis of the measured data.

This paper introduce a reinforcement method for vertical extension of a building using a rahmen frame structural system. This approach has to be carried out by considering the structural safety due to the additional weights being exerted to the pre-existing building. The connections to fasten both the rahmen frames and original building were designed with the axial loads and moments acting on the rahmen frame structural system, that is extended vertically. This system reduces the structure self-weight and ensures non-additional of reinforcement.

This study is to introduce a structural analysis method that can apply a unit modular system to a remodeling extension. The structural analysis process, which can reflect the behaviors between the existing building and the modular system, is performed in a five-staged structural analysis. Therefore, the example of structural analysis of an existing building is introduced.

This study is to establish a structural analysis method that can apply a unit modular system to a remodeling extension. Structural design has to be performed after considering the behaviors between the existing structures and the modular system because the modular system is added after the transformation of existing structures has been processed. The structural analysis process, which can reflect the behaviors between the existing building and the modular system, is introduced in a five-staged structural analysis.

In this paper, the seismic performance of RC frame with deterioration of structural capacity was evaluated by using capacity spectrum method. And the efficiency of retrofit by using infilled masonry was checked from the evaluation of its seismic capacity for various layout. As a results, it was found that the masonry infill wall increased the stiffness and strength, but reduced ductility.