• 대한전기학회논문지:시스템및제어부문D
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• 제49권5호
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• pp.257-263
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• 2000

One of the basic assumptions in the static gait design for a walking robot is that the weight of leg should be negligible compared to that of body, so that the total gravity center is not affected by swing of a leg. Based on the ideal assumption of zero leg-weight, conventional static gait has been simply designed for the gravity center of body to be inside the support polygon, consisting of each support leg's tip position. In case that the weight of leg is relatively heavy, however, while the gravity center of body is kept inside the support polygon, the total gravity center of walking robot can be out of the polygon due to weight of a swinging leg, which causes instability in walking. Thus, it is necessary in the static gait design of a real robot a compensation scheme for the fluctuation in the gravity center. In this paper, a body impedance control is proposed to obtain the total gravity center based on foot forces measured from load cells of a real walking robot and to adjust its position to track the pre-designed trajectory of the corresponding ideal robot's body center. Therefore, the walking stability is secured even in case that the weight of leg has serious influence on the total gravity center of robot.

• 한국자동차공학회논문집
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• 제18권5호
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• pp.91-99
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• 2010

The center of gravity on vehicle is a fundamentally important point for assessing and measuring the characteristics of vehicle dynamics. Especially, the center of gravity height on vehicles is the closest factor with respect to rollover accidents in a social issue nowadays. In this paper, the center of gravity height in conjunction with vehicle parameters of vehicle weight, driving axle and roof height after measured by vehicle weight and loading location by means of VCGM developed by KATRI with good performance that the accuracy was less than 0.6% and repeatability 0.3% for vehicles being used in the whole world was observed. As a result of study, the location of center of gravity height on vehicle was able to be estimated with only roof height on vehicle.

• EDISON SW 활용 경진대회 논문집
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• 제4회(2015년)
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• pp.460-466
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• 2015

The remaining features in this study using the Freecad proceeds according to the overall effect was not supported by the modeling Freecad were conducted a study to complement using the CATIA program or other commercially available. The focus of this study is that there can be obtained the stability through the center of gravity of the balancing of two parts by increasing the weight of the other magnet through a Fortuna other end of the weight of the bar, using the center of gravity. Finally, to find the optimal design of the weight and thickness of the main bar through the center of gravity balancing is the purpose of this study.

• 대한조선학회논문집
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• 제46권3호
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• pp.335-342
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• 2009

Motion characteristics of a planing craft are sensitively changed according to its weight and longitudinal center of gravity. In this paper, planing craft model tests were performed in calm water for various test conditions and Froude numbers. Sinkage and trim were measured to analyze the relations between the attitudes of a planing craft and the weight and center of gravity of it. Theoretical formula for the prediction of the attitudes of a prismatic planing hull was modified so that it can be applied to the prediction of the attitudes of a non-prismatic planing hull, and the calculation results by the modified formula were in good agreements with the experimental data.

• 한국소음진동공학회논문집
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• 제23권10호
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• pp.878-884
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• 2013

The center of gravity and the moment of inertia of railway vehicles are important parameters for running safety and stability in railway vehicle design. However, the exact measurement of those is difficult in manufacturing field. The weight measurement of a railway vehicle beneath the wheel using a weight scale is off by a large amount. This paper suggests a measurement method for the center of gravity and the moment of inertia of railway vehicles using vibration. For the measurement a railway vehicle is suspended using four wires. Direct measurement of the tension of the wires and the period of swinging motion of the suspended railway vehicle with calculations give the exact location of the center of gravity and the moment of inertia in x, y, and z directions, respectively. This implementation was demonstrated using an experimental device and verified numerically.

• International journal of advanced smart convergence
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• 제8권3호
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• pp.78-86
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• 2019

Recently, IoT researches using sensor data based on embedded networks in various fields including healthcare and sports have been continuously attempted. This study analyzes golf ball mobility to support IoT application in golf sports field. Generally, since the difference in density occurs due to the condition of the inner material and the abnormal state at the time of the outer skin joining during the manufacturing of the golf ball, the weight of each subset is equal for any two points with the same radius in the sphere cannot be guaranteed. For this reason, the deflected weight of the sphere has the undesirable effect of hitting the ball in a direction in which the weight of the ball is heavy. In this study, it is assumed that there is a unique center of gravity of the ball, and even if the golf ball cannot be manufactured perfectly, it wants to establish the basic principle to accurately recognize or mark the putting line based on the center of gravity. In addition, it is evaluated how the mobility of the golf ball with a deviation from the center of gravity of the golf ball affects the progress path (or movement direction) and the moving distance (or carry distance) after the golfer hits. The basic model of the mobility of the golf ball can help the golfer exercise model and the correlation analysis. The basic model of the mobility of the golf ball can help the golfer exercise model and the correlation analysis.

• 대한산업공학회지
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• 제11권2호
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• pp.87-99
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• 1985

The purpose of this study is to analyze the changes in centers-of-gravity (COG), acceleration and body posture and their associated effects both on EMG and on the maximum capability of weight lifting during Clean & Jerk and Snatch motions. Displacement, velocity, acceleration of joints were obtained from film analysis. Also levels of exertions on 11 major muscle groups were obtained from EMG analysis during a lifting cycle. The EMG data were measured from Telemetry System which is useful in field experiments. Magnitude and direction of force, change in center-of-gravity were extracted from COG data which were measured from force platform. The results of this study can be to be useful both to coaches and to athletes in weight-lifting.

• 한국항해항만학회지
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• 제43권1호
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• pp.16-22
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• 2019

본 연구에서는 국내 소형 어선의 재화상태에 따른 중량 및 무게중심 추정식을 제안하였다. 소형 어선에 탑재되는 중량물은 선원, 어구 등의 고정 중량과 연료, 청수, 식량, 미끼, 어획물 등의 가변 중량으로 분류할 수 있다. 다양한 소형 어선들의 중량 데이터를 통계 분석한 후, 각 탑재물의 중량 및 무게중심을 총톤수에 대하여 선형 함수화하였다. 그리고 재화상태를 고려하여 각 가변 중량물에 가중치를 부가하는 방식으로 총 중량 및 무게중심 추정식을 구성하였다. 소형 어선의 길이와 총톤수, 그리고 재화상태 정보만을 활용하여 총 중량 및 무게중심을 상당히 신뢰도 높게 추정할 수 있음을 검증하였다.

• The Journal of Korean Physical Therapy
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• 제5권1호
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• pp.61-69
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• 1993

It was performed to encourage for Physical Therapist to apply the theory of center of the human body and segments in clinical situations. This study was investigated literarily on center of the human body and segments. Methods which search for the center-2 types, that is, method using reaction broad and segmental method-was suggested. The center location difference of gravity in human body depends on individual character. Generally, the center location is in kent of 2nd sacrum, that is, at $55\%$ of height from foot. The center of each segment is on 'link'. In the first place we must how the weight of segment we can search for the center easily. Mean segment coater location of extremities is at $42.33\%$ from each proximal end, and mean center of head and trunk lies at $45\%$.

• 한국정보통신학회:학술대회논문집
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• 한국정보통신학회 2016년도 추계학술대회
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• pp.948-949
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• 2016

본 논문에서는 감마선원 영상화를 위한 감마선 탐지장치에 적용할 차폐체의 구조 변경에 대한 연구를 수행하였다. 선행 연구를 통해 상용 감마선 영상화 장치의 차폐체와 차폐효율은 유사하지만 경량화 그리고 무게중심을 이동시킨 차폐체를 구현하였다. 본 논문에서는 모션 제어장치의 효율적인 동작을 위해 차폐체를 변경하였다. 차폐체 설계를 위해서 MCNP 전산모사를 수행하였으며, 그 결과 약 15%의 경량화 및 무게중심을 차폐체 중심으로 이동시키는 결과를 얻었다.