• Korean Journal of Applied Biomechanics
• /
• v.16 no.1
• /
• pp.151-158
• /
• 2006

The purpose of this study was to find out the kinematical characteristics of arm's basic position in ballet. In order to achieve the purpose of the study, 3D cinematographic analysis was conducted with a ballerina who might performed the perfect arm's basic position. According to the results of this study, it was appeared that the shoulder kept about 78%-82%, the elbow kept about 62%-96%, the wrist kept 52%-109%, and finger kept 48%-110% with the height. Also, movement was formed with $21^{\circ}-77^{\circ}$ of the upper arm angle, $106^{\circ}-164^{\circ}$ of the elbow, $125^{\circ}-140^{\circ}$ of the wrist, and $83^{\circ}-160^{\circ}$ of the shoulder. The left-right ratio of the total arm angle was 98% in the first, second, and third position, and 100% in the forth position. The angle of arm gradient was remained $-68^{\circ}$ in the first position, $-27^{\circ}$ in the second position, $73^{\circ}$ in the third position, and $-11^{\circ}$ in the forth position. Based on the results mentioned above, balance and symmetry of both arms was an important factor in those four positions. Although it is impossible to maintain the position like robot, it may be a good performance if a certain level of extent was remained With respect to this point of view, it may be a good position if the difference between right and left arm in each joint can be remained within 2%. Angle also was an important factor that if the difference in total angle can be remained within 2% it may be an excellent position, there was difference of right and left based on the joint though. Therefore, practice and instruction to make a perfect symmetry as much as possible were needed Also, it would be a good movement if position and angle of joint within 2% difference of right and left arm can be remained In turn, because ballet is movement with expression of the body, beauty of the body and balance of the movement have to be harmonized for beautiful performance. Therefore, it would be a meaningful future study considering the body condition and movement of ballerina to define the beauty.

• Journal of The Korean Society of Integrative Medicine
• /
• v.9 no.3
• /
• pp.135-144
• /
• 2021

Purpose : The purpose of this study was to investigate the effect of 2 weeks of backward walking exercise (BWE) on cervical angle and gait parameters in college students with forward head posture. Methods : Fifteen subjects participated in the experiment. All the participants had a craniovertebral angle (CVA) of 55 degrees or less. The purpose of the study was explained to all the subjects prior to participation, and volunteered to take part in the study. A camera capable of taking pictures of the lateral plane was installed at a distance of 1.5 meters from each subject. Images of forward head posture were obtained before and after performing the BWE, and the CVA and craniorotational angle (CRA) were compared pre- versus post exercise. Foot pressure and gait parameters (step length of left and right, stride length, stance of left and right, swing of left and right, step time of left and right, and stride time) were measured using a rehabilitation treadmill. The subjects performed the BWE for 2 weeks. The exercise program consisted of a 5-minute warm-up exercise, 20-minute main exercise, and 5-minute cool-down exercise. In the main exercise, the treadmill speed was set to 2.4 km/h in the first week and 3.4 km/h in the second week. A paired t test was used to compare the CVA and CRA and gait parameters before and after the exercise. Results : Comparison of the CVA and CRA before and after the BWE revealed a significant difference post exercise, with a marked improvement in forward head posture after the exercise (p<.05). Conclusion : Based on the results of this study, the BWE is considered to be an effective exercise for the forward head posture. Also, additional research is needed to shed light on the impact of the BWE on gait parameters.

• Korean Journal of Applied Biomechanics
• /
• v.25 no.1
• /
• pp.131-140
• /
• 2015

Purpose : The purpose of this study was to analyze the coordination of the trunk tilting angle and bilateral lower limbs according to the stirrups length during trot in equestrian. Methods : Participants selected as subject were consisted of adult male(n=7, mean age: $45.00{\pm}3.78yrs$, mean height: $172.50{\pm}2.44cm$, mean body mass: $76.95{\pm}4.40kg$, mean, mean leg length: $97.30{\pm}2.60cm$). They were divided into 3-types of stirrups lengths(67 cm, 72 cm, 77 cm) during trot. The variables analyzed were consisted of the trunk front-rear angle, lower limb joint(Right Left hip, knee, ankle), overall movement index(OMI) of the lower limbs(thigh, shank, foot) and asymmetry index(AI%) during trot. Results : The average angle in hip and knee joint showed more extended posture according to the increase of stirrups lengths and ankle angle showed more plantarflexion posture according to increase of stirrups length during 1 stride in trot. Also, average angle showed more extended posture in right hip and ankle joint than that of left. The angle of knee joint didn't show significant difference statistically between right and left. Also asymmetric index in average angle of hip, knee and ankle joint didn't show significant difference statistically in between lower limbs, but hip joint showed higher asymmetric index in stirrup length of 77 cm and ankle joint showed higher asymmetric index in stirrup length of 67 cm than that of the others respectively. The FR angle in trunk of horse-rider showed relative backward leaning motions at stirrup length of 67 cm and 77 cm than that of stirrup length of 72 cm during stance and swing phase. OMI in thigh, shank, and foot limbs didn't show significant difference statistically according to the stirrups length of right and left lower limbs, but left lower limbs showed higher index than that of right lower limb. Stirrup length of 72 cm in shank and foot limbs showed higher index than that of stirrup length of 67 cm and 77 cm. But stirrup length of 72 cm showed higher asymmetric index than that of stirrups length of 67 cm and 77 cm. Conclusions : When considering the above, 72 cm(ratio of lower limb 74.04%) stirrup lengths could be useful in posture correction and stabilization than 67cm(ratio of lower limb 68.69%) and 77 cm(ratio of lower limb 79.18%) stirrup lengths during trot in horse back riding.

• Journal of Technologic Dentistry
• /
• v.18 no.1
• /
• pp.117-127
• /
• 1996

This study was aimed to help the construction of esthetic dental prosthesis by investigation of the factors affecting on the atterition position and attrition angle of maxillary lateral incisors. Therefore 197 complete cast of maxillary and mandibualar extracted form the student of K. college were subjected for this study, and result throught the study are as follows. 1. None attrite rate of the maxiilary right lateral incisors was about 16.2% and that of the maxillary left lateral incisors was about 32.4% of examined teeth. 2. Throught mesiodistal attrition area 1) It showed that right lateral incisors was the most frequence in attrition of mesial area of incisal edge, and left lateral incisors was the most frequence in attrition of mesial and mid area of incisal edge. 2) It showed that square type arch was more frequence in attrition of all incisal edge, and ovoid type arch was more frequence in the attrition of mid area of incisal edge, and ovoid type arch was more frequence in the attrition of mid area of incisal edge, and taper type arch was more frequence in the attrition of mesial area of incisal edge than it of average frequence of right lateral incisors, by dental arch type. 3) It showed that square type arch was more frequence in the attrition of all area and mid area of incisal edge, and ovoid type arch was more frequence in the attrition of mid area of incisal edge, and taper type arch was more frequence in the attrition of mesial and distal area of incisal edge than it of average frequence of left lateral incisal, by dental arch type. 4) Sex, vertical overlap, horizontal overlap, incisal guide angle, did not affect significantly to throughout mesiodistal attrition, statistically 3. Throughout labiolingual attrition quantity. 1) It showed that throughout labiolingual attrition quantity was more attrition in order of taper type arch < ovoid type arch < square type arch, by dental arch type. 2) It showed that throughout labiolingual attrition qauntity was more attrition when the length of horizontal overlap is shorter than it of other, by horizontal overlap. 3) Throughout labiolingual attrition quantity of right lateral incisors showed that male was more attrition than it of female. 4) Vertical overlap, incisal guide angle, sex on left lateral incisors did not affect significantly to throughout labiolingual attrition, statistically. 4. Attrition angle 1) It showed that average attrition anlge of right lateral incisors were $30{\pm}13.02$ degree, and it of left lateral incisors were $26{\pm}13.37$ degree. 2) It showed that taper type arch have a bigger attrition angle than it of average of lateral incisors, and square tape arch have a smaller attrition angle than it of average of lateral incisors, by dental arch type. 3) It showed that horizontal overlap of 2.1mm above have a bigger attrition angle than it of average, by horizontal overlap. 4) It showed that female have a bigger attrition angle it of male, by sex.

• Archives of Craniofacial Surgery
• /
• v.11 no.1
• /
• pp.45-48
• /
• 2010

Purpose: After surgical interventions of mandible fractures, facial asymmetry can be occurred, and it leads to serious problems for patients. This can be solved by mandible angle ostectomy. Methods: A 19-year-old male underwent percutaneous surgical intervention for left mandibular angle and right parasymphyseal fractures 3.5 years ago. The left angle was protruded compared to the other side. Using a percutaneous approach, $4.5{\times}1cm$ sized piece of mandible angle was sawed off. For the right angle, intraoral approach was performed for angle ostectomy, and the angle was sawed off by a size of $4{\times}1cm$, using a pattern based on the piece from the left side. Results: After surgery, no complications such as subcondylar fractures, refractures, insufficient corrections, secondary angle formations, hematomas, and transient nerve palsies were seen, and symmetric correction of mandible angles were done. Conclusion: In facial asymmetries due to mandibular fractures, mandible ostectomy could be a solution. Using the bone section from the contralateral side, measurement of the amount of bone sawed off was possible, and via percutaneous approach on the previously operated site with simultaneous scar revision, and intraoral approach for the contralateral side, cosmetically satisfactory result was obtained.

• The Journal of Korean Physical Therapy
• /
• v.27 no.3
• /
• pp.154-158
• /
• 2015

Purpose: The purpose of this study was to propose a new reference point for measurement of the infrasternal angle and to investigate the intra- and inter-rater reliabilities of infrasternal angle measurement using photographs. Methods: Twenty-four healthy male college students participated as subjects in this study. Photographs were taken of subjects in two postures, one standing with the shoulders relaxed and one standing with the shoulders at $150^{\circ}$ abduction. All photographs were analyzed using Image J software. Raters used the photographs to measure the infrasternal angle between the xiphoid process, the medial margin of rib and navel on the right and left sides. The reliability of the infrasternal angle measurement was assessed by means of intraclass correlation coefficients [ICC (3,1)]. The level of statistical significance was set at p<0.05. Results: The intra- and inter-rater reliabilities of the infrasternal angle measurement for the right side at rest were excellent (ICC=0.866 and 0.813, respectively), as were those for the left side at rest (ICC=0.919 and 0.846, respectively). At $150^{\circ}$ shoulder abduction, the intra- and inter-rater reliabilities for measurement of the infrasternal angle on the right side were excellent (ICC=0.972 and 0.778, respectively), as were those for the left side (ICC=0.914 and 0.826, respectively). Conclusion: These findings suggest that this technique can be successfully used to measure the infrasternal angle, thus suggesting a new reference point for determining the length of the internal oblique and external oblique muscles in clinical situations.

• Physical Therapy Korea
• /
• v.12 no.1
• /
• pp.45-54
• /
• 2005

The quadriceps-angle (Q-angle) and the ratio of hamstring/quadriceps (H/Q) are important for the stability of the knee and for protection from excessive stress. The aim of this study was to examine the association between Q-angle and H/Q ratio with and without knee osteoarthritis. We compared knee osteoarthritis patients with symptom-free women. The mean age of the patients in the arthritis group (25 women, osteoarthritis) was 59.7 years. The non-arthritis group consisted of 25 women with a mean age of 55.2 years. Of the 25 women with osteoarthritis, 5 had the condition in their left knee, 5 had it in their right knee, and 15 had it on both sides. There was no significant difference in the knee Q-angle of the left and right knees of the arthritis group and the non-arthritis-group (p>.05). The strength of all the muscles around the involved right knee in the arthritis group was significantly weaker than that of the non-arthritis group (p<.05). However, in the left knee, only the strength of the knee extensors and internal rotators was significantly weaker than that of the non-arthritis group (p<.05). The Q-angle was not associated with the H/Q ratio and internal rotators/external rotators ratio of the involved knee in the arthritis group (p>.05). Neither was the Q-angle associated with the pain level of an involved knee in the arthritis group (p>.05). The knee pain was not associated with the H/Q ratio of the involved knee in the arthritis group (p>.05). The Q-angle was not associated with the ratio of H/Q and pain level of the involved knee in the osteoarthritis women.

• Journal of the Korean Society of Safety
• /
• v.29 no.6
• /
• pp.81-86
• /
• 2014

Composite materials have high specific stiffness, specific strength than existing concrete or steel materials. It has superior dynamic properties when utilizing advantages of material such as Non-corrosive, light weight, non-conducting and it has superior mold ability which can make variable shapes. Thus, in the construction, for using composite materials as construction materials, the study carried out static strength of fiber right angle direction and fatigue performance of FRP deck member. The study is going to deduct S-N curve by analyzing the results comparatively and estimate long-term durability. From now on, the study is going to provide interpretation of FRP member and basic data of design basis, furthermore providing foundation technique of composite materials' application of structural frame is the goal of this study.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2000.05a
• /
• pp.124-127
• /
• 2000

This paper describes the algorithm for more fast tracking by compensation of the staring angle of antenna to receive the satellite signal changed by the mobile vehicle direction. The staring angle is compensated by signal processing from the electronic compass which is called VECTOR2X, and a left-right tracking method. Especially, when mobile vehicle is turning with high speed, it is observed a result which has more fast tracking time by using angle tracking technique compensated by electronic compass than one by only left right tracking method.

• Proceedings of the KIEE Conference
• /
• 2002.07c
• /
• pp.1985-1987
• /
• 2002

Silicon bulk micromachined micromirrors are designed and fabricated for out-of-plane right angle reflection. The micromirror is comprised of a minor plate, springs, magnetic bars and electrodes. Single crystalline silicon is used for a flatness improvement of a mirror plate. Out-of-plane right angle reflection requires a 45 degree operation of the micromirror. The micromirrors are operated by applying a magnetic field, which is generated by a coil located below a substrate. For an individual mirror operation, each mirror is clamped using an electrostatic force against the electromagnetic force. Angular deflections are measured and compared with theoretical data. The micro mirror operates up to 45 degree when magnetic field is 4 kA/m which is generated by a 115 mA coil current Simple addressing is tested, and it is shown that a clamping voltage is less than 5V.