• 해양환경안전학회지
• /
• 제22권7호
• /
• pp.800-806
• /
• 2016

예부선이 항행할 경우 부선의 회두운동으로 인하여 예선은 조종성능에 제한을 받기 때문에 부선의 회두운동을 감소시켜야 안전한 예항업무를 이행할 수 있다. 본 연구에서는 부선의 침로안정성을 향상시키기 위한 방안으로 부선의 회두운동에 영향을 미치는 항목들을 조사하기 위하여 수조실험을 실행하였다. 선수 형상에 따라 회두운동 특성이 다르게 나타나기 때문에 서로 다른 선수 형상을 지닌 부선 모델을 대상으로 스케그의 영향, 예인선속의 영향, 예인삭 길이의 영향, 브라이들의 영향에 대하여 종합적으로 분석하였다. 실험결과 스케그의 설치 위치에 의한 효과는 선수형상에 따라서 다르게 나타나고 있는 모습을 보여주고 있다. 부선의 회두운동은 부선에 연결된 예인삭의 길이가 길수록 부선의 회두가 작아짐을 알 수 있었다. 또한 예인삭만 연결한 상태보다 예인삭에 브라이들을 연결하는 것이 부선의 회두가 작아지며, 브라이들의 길이가 길어질수록 부선의 회두운동이 크게 작아짐을 알 수 있었다.

• 한국전문물리치료학회지
• /
• 제25권3호
• /
• pp.12-18
• /
• 2018

Background: Passive straight leg raising (PSLR) is the common clinical test to measure of hamstring muscle length. Hip flexion angle contributes to change the lumbopelvic rotation during PSLR. Pressure biofeedback unit (PBU) is commonly used to detect lumbopelvic movement during lower limb movements. Thus, there may be the relationship between pressure of PBU and lumbopelvic motion during PSLR. Objects: The objective of this study was to determine the relationship between pressure of PBU and lumbopelvic motion during PSLR. Methods: Thirty two subjects participated in this study. A three-dimensional motion analysis system were used to measure the lumbopelvic angle during PSLR, while recording the pressure of PBU according to angle of PSLR by 10 degree increments. Pearson product moment correlations and linear regression analysis were used to describe the relationship between variables. Results: The results showed that there was a significant relationship between the lumbopelvic and angle of PSLR (Pearson's r=.83, p<.05), between the pressure of PBU and angle of PSLR (Pearson's r=.75, p<.05), and between lumbopelvic motion and pressure of PUB (Pearson's r=.83, p<.05). Linear regression equation using lumbopevic angle as an independent factor was as follows: Pressure of PBU = 47.35 + (2.55 ${\times}$ angle of lumbopelvic motion) ($R^2=.69$, p<.05). Conclusion: Results of the present study indicate that pressure of PBU can be used to indirectly detect the amounts of lumbobevic motion during muscle length test or stretching of hamstring.

• International Journal of Automotive Technology
• /
• 제6권2호
• /
• pp.183-190
• /
• 2005

During normal operating conditions, a motor vehicle is constantly subjected to a variety of forces, which can adversely affect its straight-ahead motion performance. These forces can originate both from external sources such as wind and road and from on-board sources such as tires, suspension, and chassis configuration. One of the effects of these disturbances is the phenomenon of vehicle lateral-drift during straight-ahead motion. This paper examines the effects of road crown, tires, and suspension on vehicle straight-ahead motion. The results of experimental studies into the effects of these on-board and external disturbances are extremely sensitive to small changes in test conditions and are therefore difficult to guarantee repeatability. This study was therefore conducted by means of computer simulation using a full vehicle model. The purpose of this paper is to gain further understanding of the straight-ahead maneuver from simulation results, some aspects of which may not be obtainable from experimental study. This paper also aims to clarify some of the disputable arguments on the theories of vehicle straight-ahead motion found in the literature. Tire residual aligning torque, road crown angle, scrub radius and caster angle in suspension geometry, were selected as the study variables. The effects of these variables on straight-ahead motion were evaluated from the straight-ahead motion simulation results during a 100m run in free control mode. Examination of vehicle behavior during straight-ahead motion under a fixed control mode was also carried out in order to evaluate the validity of several disputable arguments on vehicle pull theory, found in the literature. Finally, qualitative comparisons between the simulation results and the test results were made to support the validity of the simulation results.

• 정형스포츠물리치료학회지
• /
• 제14권2호
• /
• pp.1-8
• /
• 2018

Purpose: This study investigated the effect of the augmented reality (AR)-based knee joint short period exercise program and used a motion analyzer with a 3D camera to determine the range of motion and dynamic balance and further investigate the effects of therapeutic exercise on patients. Methods: This study used AR-based motion analysis and a Y-balance test to measure the range of motion (ROM) of each joint: the hip joint and the knee joint. After the measurements, an exercise program was applied to the subjects, using the knee motion program function, and the muscles of the quadriceps femoris and the hamstring were stretched or strengthened. Results: Our results showed knee joint extension at the dominant hip joint flexion position. While there was no significant difference (p>.05) at this position, there were significant differences in the non-dominant hips, unbalanced knee joint flexion, and superior knee joint flexion (p<.05). The Y-balance test using the non-dominant leg supported by the dominant legs showed that the absolute reach was $69.70{\pm}7.06cm$ before the exercise, and the absolute reach after the exercise was $77.56{\pm}6.09cm$ (p<.05). Conclusions: There was a significant difference when the movement of the lower limbs supported the superior limbs, and a significant difference was found in the ROM when the non-dominant side supported the dominant side. Therefore, the AR-based exercise program improves the balance of the human body and the range of motion of the joints, and research that aims to improve patients abilities should continue.

• Journal of Astronomy and Space Sciences
• /
• 제32권4호
• /
• pp.341-348
• /
• 2015

New observations for the times of minimum lights of a well-known apsidal motion star CW Cephei were made using a 0.6 m wide field telescope at Jincheon station of Chungbuk National University Observatory, Korea during the 2015 observational season. We determined new times of minimum lights from these observations and analyzed O-C diagrams together with collected times of minima to study both the apsidal motion and the Light Time Effect (LTE) suggested in the system. The new periods of the apsidal motion and the LTE were calculated as 46.6 and 39.3 years, respectively, which were similar but improved accuracy than earlier ones investigated by Han et al. (2002), Erdem et al. (2004) and Wolf et al. (2006).

• 한국해양공학회지
• /
• 제6권1호
• /
• pp.19-28
• /
• 1992

The motion of a cylindrical object resting on shallow seabed due to wave forces and soil friction is studied. Given environmental conditions such as wave characteristics and seabed soil properties, the equations of motion are derived and the corresponding reponses of the cylinder in two dimensional plane, i.e., translational and rotational displacements, accelerations, are calculated. The motion is substantially restrained by the penetration of a cylinder into seabed and the parametric study focuses on finding out a minimum penetration depth which makes the cylinder motionless.

• 한국콘텐츠학회논문지
• /
• 제6권9호
• /
• pp.116-123
• /
• 2006

본 연구에서는 게임캐릭터가 단순행동에서 감정상황에 대한 동작연기로 발전되기를 기대하며 접근을 하였다. 게임캐릭터가 다양한 상황을 표현하고 감정을 부여하는 매개자로서 역할을 부여하고, 표현하는 동작을 마임연기자동작에서 추출하여 3D캐릭터에게 동작 연기별로 적용시켜 표현하였다. 동작연기는 기본동작에서 희, 노, 애, 락의 감정별 단계로 확대하였고, 상징적 언어상황에 대한 반의적 감정연기를 통하여 의사전달을 분명히 하고, 다양한 시각에서 표현되는 동작연기를 제시하였다.

• 한국정밀공학회:학술대회논문집
• /
• 한국정밀공학회 2004년도 추계학술대회 논문집
• /
• pp.359-363
• /
• 2004

Numerous studies have been performed to analyze various phenomena of human's walking, gait. In the present study, unrecognized walking and recognized walking were analyzed by three dimensional motion capture system(VICON motion system Ltd., England) and simulated by computer program. Two normal males participated in measuring the motion of unrecognized and recognized walking. Six infrared cameras and four force plates were used and sixteen reflective markers were attached to the subject to capture the motion. A musculoskeletal model was generated anatomically by using ADAMS(MSC software corp., USA) and LifeMOD(Biomechanics Research Group Inc, USA). The inverse dynamic simulation and forward dynamic simulation were also performed. The result of simulation was similar to the experimental result. This study provides the base line for dynamic simulation of the falling walking. It will be useful to simulate various another pathologic gaits for old peoples.

• The Journal of Korean Physical Therapy
• /
• 제17권2호
• /
• pp.1-10
• /
• 2005

This study is going to have been recognized a change of Cervical range of motion with the object 40 persons who sat for many hours before computer. According to the therapy term, sling used joint mobility exercise and Mckenzie was executed by 20 persons Shared. The study results about the effect that Cervical exercise had on joint Range of motion of a VDT syndrome patient were as follows. 1. There was a similar difference a sling used in Cervical Range of motion of joint mobility exercise cure after one-week, two-weet and three-week. 2. The change Cervical Range of motion of Mckenzie exercise has not been after one-week and two-week but a similar difference happens after three-week. 3. There has not been difference between joint mobility exercise and Mckenzie exercise in cure ferm sling used.

• 한국안전학회지
• /
• 제21권3호
• /
• pp.122-126
• /
• 2006

This study investigated effect of arm posture, wrist motion repetition and external load on perceived discomfort through an experiment. Eleven female college students participated in the experiment, where shoulder, elbow and wrist motion, wrist motion repetition, and external load were used as independent variables. The results showed that only external load had a significant effect on perceived discomfort. The perceived discomfort linearly increased with external load. Based on the results of this and the previous study for males, it was concluded that effect of external load on perceived discomfort was larger than that of other posture and motion repetition related variables. This implies that effect of external load is the most important factor considered in the first place when assessing postural load.