• Korean Journal of Applied Biomechanics
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• v.14 no.1
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• pp.145-160
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• 2004

The purposes of this study to provide quantitative data in necessary to advance techniques kinematic analysis of Cucarachas which is an action of Rumba. Then, this study is performed on 5 female players who have won within the third prize at a national athletic meeting. When whole foot reached to floor, Displacement of right-left hip joint (until $E1{\sim}E3$ average moved 15.15cm)is found at right-left direction since the hip joint is turned to right back. On the other side, large displacement is shown because Rumba Cucaracha Movement is expressed by maximum shift of hip joint to right and left direction. Displacement of right hip joint(E3$57.40{\pm}7.46$) is found in front and in rear direction since hip joint is moved in rear and in front to turn the hip joint. It may be stated that this is ideal displacement expressed by movement of whole body with artistic poise and presentation because role of hip joint is very important in technical and artistic side. Angle of right shoulder joint E2($105.44{\pm}9.64$) is got wider. It may be stated that player shifts up and abduct elbow joint to right since center of gravity of player is exceedingly shifted to right in this motion of Cucarachas. On the other hand, since this motion is abducted right elbow and shrunk external abdominal oblique to him center of body to left front of hip joint, the angle becomes narrow. It is shown that angle of knee in right knee joint E4($75.44{\pm}2.61$) is large since right leg and hip joint is turned by foot using reaction of ground and so center of body is shifted to left. Large angle of ankle E4($134.40{\pm}10.50$) in Cucaracha Movement is shown by the action of twist force using narrow part of foot and compression force against ground with adduction speed of arm. The various kinematic analyses associated with motions of dance sport have not been sufficiently peformed so far, and thus a number of research projects for dance sport should be proposed and performed to be continuous.

• 제어로봇시스템학회:학술대회논문집
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• 2004.08a
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• pp.466-469
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• 2004

In this paper, we improve the matching impedance of antennas by inserting parasitic slots on the ground plane of right-angle triangular slot antennas. The designed antennas characteristics are analyzed by using Finite Different Time Domain (FDTD) method, the specific design frequency is 10 GHz and match impedance is 50 ohms. Simulation results show that the efficient of return loss and radiation patterns are improved and enhance. In this case, the right-angle triangular slot antennas with parasitic slots have matching impedance better than antennas without parasitic slots.

• Proceedings of the KSME Conference
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• 2001.06e
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• pp.317-322
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• 2001

This study depicts an experimental work of the impulsive wave discharged from the open end of several kinds of right-angle bend pipes, which are attached to the open end of a simple shock tube. The weak normal shock wave with its magnitude of Mach number from 1.03 to 1.20 is employed to obtain the impulsive wave propagating outside the open end of the bend pipes. The experimental data of the magnitude of the impulsive wave and its propagation directivity are analyzed to characterize the impulsive waves discharged from the right-angle bend pipes and compared with those from a straight pipe. The results obtained show that a right-angle miter bend considerably reduces the magnitude of the impulsive wave and its directivity toward to the pipe axis, compared with the straight pipe. It is believed that the right angle miter bend pipe can playa role of passive control against the impulsive wave.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.29 no.11
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• pp.18-27
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• 2015

In this paper, we proposed the spinning right-angle stereo vision system to center the shifted object on 3-dimensional image using a human eyesight-like, and the system is reconstructed with conventional stereo vision system. In this proposed system, the centering results of objects on the 3-dimensional image are very good, and we got the parameter ratios 89~112% for the real measurement values. Therefore, the suggested the spinning right-angle stereo vision system have a high possibilities to be applied to many industrial system parts and to be used for robot system, automatic system, and etc.

• Korean Journal of Applied Biomechanics
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• v.17 no.3
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• pp.11-21
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• 2007

The purpose of this study was to examine the differences of kinematics and muscle activities depending on the changes of angle approaching balls during backhand drive in squash. The results are as follows. Stride time took the longest at AD2 and step lengths were the biggest at AD1 of left foot contact and right foot contact and AD2 of impact and follow-through. The center of gravity and the speed of racket head were the highest at AD3 and at AD2. Angle of shoulder joint were the biggest at AD1 of left foot contact, right foot contact and impact and AD3 of follow-through. Angle of elbow joint were the biggest at AD3 of left foot contact, right foot contact and follow-through and AD2 of impact. Angle of pelvis joint were the biggest at AD2 of left foot contact, AD1 of right foot contact and AD3 of impact and follow-through. Angle of knee joint were the biggest at AD2 of left foot contact, AD1 of right foot contact and AD3 of impact and follow-through. Angle of ankle joint were the biggest at AD1 of left foot contact and AD3 of right foot contact, impact and follow-through. According to the analysis results of triceps brachii, latissimus dorsi, brachioradialis muscle and flexor carpi ulnaris muscle activities were high at AD1 of all phases. Analysis results of vastus lateralis, vastus medialis, tibialis anterior and gastrocnemius medial muscle activities were high at AD2 of phase1 and phase3. Those of vastus lateralis, vastus medialis and tibialis anterior, gastrocnemius medial were high at AD3 of Phase 2 and AD1 of phase2.

• Physical Therapy Korea
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• v.25 no.4
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• pp.19-26
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• 2018

Background: Alignment of the lower limb is an important factor, influencing balance and gait in kinematics and kinetics, in patients with and without a flat arched foot. Flat arched foot are associated with the range of motion (ROM) of the hip and alignments of the knee joints, is strongly influenced. Objects: The purpose of this research was to investigate the relationship between hip joint ROM and quadriceps angle (Q-angle), by dividing them into two groups according to the presence or absence of flat feet, using a navicular drop test (NDT) and resting calcaneal stance position (RCSP). Methods: Forty elderly patients were allocated to the experimental group (flat foot group, n1=20) or the control group (non-flat group, n2=20). Universal and digital goniometer, tractograph and tape measure were used to determine the related changes in the hip ROM, Q-angle, NDT and RCSP. Results: Data were analyzed using the Pearson correlation coefficients. Active internal ROM of the hip joint (right, r=.803, p<.001), (left, r=.951, p<.001) were highly correlated with NDT, and also, was moderately correlated with Q-angle (right, r=.562, p=.019), (left, r=.757, p<.001). Passive internal ROM of the hip joint (right, r=.742, p=.001), (left, r=.922, p<.001) were highly correlated with NDT, and also, was moderately correlated with RCSP (right, r=-.530, p=.029) and with Q-angle (right, r=.710, p=.001), (left, r=.698, p=.002) in the flat foot group. However, no strong correlation among the hip ROM, NDT, RCSP and Q-angle were found in the non-flat foot group. Conclusion: This research may provide evidence of the correlations between hip internal ROM and flat foot.

• Korean Journal of Applied Biomechanics
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• v.15 no.4
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• pp.181-189
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• 2005

To know the proper impact posture and changes for the various clubs, changes of impact variables according to the change of golf club length was investigated. Swing motions of three male low handicappers including a professional were taken using two high-speed video cameras. Four clubs iron 7, iron 5, iron 3 and driver (wood 1) were selected for this experiment. Three dimensional motion analysis techniques were used to get the kinematical variables. Mathcad and Kwon3D motion analysis program were used to analyze the position, distance and angle data in three dimensions. Major findings of this study were as follows. 1. Lateral position of the head remained more right side of the target up to 3.5cm compared to the setup as the length of the club increased. 2. Left shoulder raised up to 5cm and right shoulder lowered up to 2.5cm compared to setup. The shoulder line opened slightly (maximum 11 degrees) to the target line. 3. Forward lean angle of the trunk decreased up to 4 degrees (more erected) compared to setup. 4. Side lean angle of the trunk increased compared to setup and increased up to 16 degrees as the club length increased. 5. The pelvis moved to the target line direction horizontally and opened up to 31 degrees. Right hip moves laterally to the grip position at the setup. 6. Flexion of the left leg maintained almost constantly but the right leg flexed up to 11 degrees compared to setup. 7. Left arm is straightened but the right arm flexed about 20degrees compared to straight. 8. Center of the shoulders were in front of the knees and toes of the feet. 9. Hands moved to the left (8.7cm), forward (5.7cm) and upward (11.6cm) compared to the setup. This is because of the rotation of pelvis and shoulders. 10. Shaft angle to the ground was smaller than the lie angle of the clubs but it increased close to the lie of the clubs at impact.

• The Journal of Korean Academy of Orthopedic Manual Physical Therapy
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• v.20 no.2
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• pp.9-14
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• 2014

Background: This study aims to examine correlations between quadriceps angle, lower extremity muscle strength and leg length discrepancy. Methods: This study selected 96 healthy women university students as the subjects of research. Quadriceps angle, lower extremity muscle strength and leg length discrepancy were measured. The statistical analysis of the data SPSS/window (version 12.0) were analyzed using the pearson correlation analysis. Results: There were negative correlations between the muscle strength of the right hamstring muscles and the right quadriceps angle in supine and standing positions. Functional leg length discrepancy of left and right quadriceps angle in supine and standing position showed positive correlations. Conclusions: The quadriceps angle affect the knee. An abnormal angle caused weakening of balance. Muscle strength, leg length discrepancy, and affected lower extremity alignment and knee function. These conclusions may prevent exercise limitation or disorders in the subjects and treating the patients with knee injury or patellofemoral pain syndrome with basic therapy intervention.

• Journal of the Korean Society of Clothing and Textiles
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• v.12 no.1 s.26
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• pp.45-52
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• 1988

To classify the foot type, direct measurements, metatarso-phalanx angle and foot print angle of the right and left foot were measured and analyzed. The results are as follows. 1. The correlation coefficients between right and left foot were high degree, and except medial malleous height, the diffences between right and left foot are not significant. 2. The correlation coefficient among direct measurements of the foot are high degree, tut the correlation coefficients between direct measurements and metatarso-phalanx angle and foot print angle are no or low degree. Therefore, to recognize the foot type, the direct measurements, metatarso-phalanx angle and foot print angle need to be measured independently. 3. According to foot width/foot $length{\times}100$ which is the slender degree of foot, three groups are distinguished: one is slender type of which foot width/foot $length{\times}100$ is less than $40.14\%$, two is standard type of which foot width/foot $length{\times}100$ is $40.14\%{\~}44.30\%$, three is broad type of which foot width/foot $length{\times}100$ is more than $44.30\%$. 4. On the photographs metatarso-phalanx angle was measured, and two groups are distinguished: one is normal type of which the metatarso-phalanx angle is more than $160^{\circ}$ and the other is the deformed type of which the metatarso-Phalanx angle is less than $159^{\circ}$. 5. By foot print angle $30^{\circ}$ which need reformation of the foot, two groups are distinguished: one is normal foot print angle of which the angle is more than $30^{\circ}$ and the other is flat foot print angle of which the angle is less than $30^{\circ}$. 6. Classifications by foot width/foot $length{\times}100$, metatarso-Phalanx angle and foot Print angle are put together, and then foot types are classified into 12 groups such as Table 11.

• Korean Journal of Applied Biomechanics
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• v.15 no.4
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• pp.55-66
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• 2005

The present study used a video analysis system to quantify the kinematical data of step shoot motion by male university handball players. From the results of analyzing dynamic variables of step shoot motion according to shooting direction were drawn conclusions as follows. 1. The height of release was proportional to the height of players, and the height of release appeared low in left-side attacks. This is probably because the left-right-throwing angle is larger in left-side attacks than that in center attacks and right-side attacks and, as a result, the throwing arm is lowered down in throwing. 2. The leftward inclination angle of the body was larger in order of right-side attacks > center attacks > left side attacks. 3. Players' throwing form was close to three quarter style in left-side attacks. In center and right-side attacks, the arm was somewhat more upright but still it was more three quarter style than overhand style. 4. The front-rear throwing angle at the moment of release was much higher in right-side attacks than in left-side ones. This is probably because the point of time for releasing the ball is usually late in right-side attacks and, as a result, the front-rear throwing angle becomes quite large. 5. The contribution of body parts on the ball speed was higher in order of the forearm > upper arm, hand > shoulder joint. 6. In players whose distance between the two legs at the moment of release, their body usually did not incline to the side much. Thus it is considered necessary to correct the right leg in their shooting motion. 7. According to the result of analyzing throwing form, the speed of the ball at the moment of leaving the hand was faster in right-side attacks than in left-side and center attacks.