• Journal of Oral Medicine and Pain
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• v.20 no.1
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• pp.195-204
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• 1995

The purpose of this study was to evaluate effect of head posture change on initial occlusal contacts through measuring the distances between initial occlusal contacts and maximum intercuspal position at different head posture. Two special devices were designed and constructed. Mandibular movement replicator was used to assess reliability of the K6 diagnostic system(MKG; Myo-tronic Inc, Seatle, USA) and head posture calibrator was used to maintain the constant head posture during experiment. We measured difference of distance between initial occlusal contact and maximum intercuspal position with MKG in upright, supine, 45 degrees extension, 30 degrees flexion, 30 degrees right and left bending postion of the head. The Frankfurt horizontal plane was used as a reference plane. 21 adults aged from 23 to 25 were selected, who have normal or class I molar relationship, and have no symptoms on TMJ and masticatory muscles, and have restorations less than 3 surfaces on each tooth, and have no other prosthetic restoration. The obtained results were as follows : The mean absolute distances between initial occlusal contact and maximum intercuspal postion were 0.39(0.18mm in the upright position, 0.65(0.37mm in the supine position, 0.59(0.33mm in the 45 degree extension, 0.70(0.53mm in the 30 degrees flexion, 1.12(1.10mm in the 30 degrees right bending and 1.94(0.67mm in the 30 degrees left bending of the head. The positions of the initial occlusal contacts have a tendency to locate anterior, left and inferior to maximal intercuspal position in upright position, posterior and inferior in supine position and 45 degrees extension, anterior and inferior in 30 degrees flexion, right and inferior in 30 degrees right bending, and left and inferior in 30 degrees left bending of the head. There were significant differences among the initial occlusal contacts in each head postures(P<0.0001). Therefore, we need to check initial occlusal contacts in the altered head posture during occlusal analysis and adjustment of occlusal appliance and dental occlusion for diagnosis and treatment of temporomandibular disorder.

• Korean Institute of Interior Design Journal
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• v.17 no.3
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• pp.131-138
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• 2008

This research is on a seating posture happening at a chair in a cinema and looked into various changes in a posture through the analysis of bodily movement in a established space like a cinema. Through the behavioral analysis of a seating posture in a limited space, each behavioral characteristic shown by a male and female and interdependent relations with a limited space were grasped. The conclusion through the above research work was as follows: 1) This research suggested a frame of analysis by dividing a seating posture into the side and upper part and was able to analyze its subsequent change characteristic of a seating posture by a male and female. 2) As for the side posture, a male was found to change fewer postures than a female, but as for the upper posture, there appeared a high frequency in posture change in case of a female. 3) As for time of staying in the side posture, a female was found to keep up a specific posture, and relatively a male changes his postures frequently while appreciating a movie; likely, as for the upper posture, it was found out that there existed a difference between the preference for the upper posture and time to keep it up. 4) A male and female were establishing a comfortable environment through their change in a posture, and there appeared changes in a posture the most within every 10 minutes in both the side and upper part postures. 5) As for the correlation between a initial posture and keep-up posture, it was found that a male tend to pursue a comfortable posture as time goes by, while a female kept up a comfortable one from her initial seating posture.

• Proceedings of the KIEE Conference
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• 2001.11c
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• pp.301-303
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• 2001

This paper deals with the biped robot gait on changing the initial postures. Gait of a biped robot depends on the constraints of mechanical kinematics and initial posture. Also biped robot's dynamic walking stability is investigated by ZMP(Zero Moment Point). The path trajectory. with the knee joint bent like a human, is generated and applied with the above considerations. To decrease trajectory tracking error, in this paper, a new initial posture similar to bird's case is proposed and realized with the real robot.

• Journal of Institute of Control, Robotics and Systems
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• v.8 no.10
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• pp.890-897
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• 2002

This paper deals with the reduction of trajectory tracking error by changing the initial postures of a biped robot. Gait of a biped robot depends on the constraints of mechanical kinematics and the initial states including the posture. Also the dynamic walking stability in a biped robot system is analyzed by zero moment point(ZMP) among the stabilization indices. Path trajectory, in which knee joint is bent forward like human's cases, is applied to most cases considered with above conditions. A new initial posture, which is similar to bird's gait, is proposed to decrease trajectory tracking error and it is verified through real experimental results.

• Journal of Advanced Navigation Technology
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• v.26 no.4
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• pp.235-243
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• 2022

In this paper, in the case of an inertial navigation system, the posture estimation error in the initial alignment due to vertical deflection is analyzed. Posture estimation error due to DOV was theoretically analyzed based on the speed and posture error of INS. Simulations were performed to verify the theoretical grinding, and the results were in good agreement. For example, in the case of η=20", an alignment error of ϕ_N=0.00287°, ϕ_U=0.00196° occurred, and in the case of 𝜉=20", an error of ϕ_E= -0.00286° occurred. Through this, it was confirmed that the vertical posture error caused by the DOV occurred as a coupling characteristic of the INS posture error. It has been shown that an additional posture error may occur due to the DOV, which was not considered in the existing INS alignment, which means that correction for the DOV must be considered when applying high-precision INS.

• Proceedings of the IEEK Conference
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• 2006.06a
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• pp.947-948
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• 2006

This paper proposes a robust posture stabilization control method for wheeled mobile robots. To solve the robust posture stabilization, we introduce reference generation mode, reference tracking mode, and reference regulation mode. In reference generation mode, a kinematic time-invariant controller is used to generate the reference trajectory which starts from the initial posture of the actual robot to the desired posture. In reference tracking mode, a sliding mode position controller is employed in such a way that the actual robot can follow the reference trajectory in the desired forward or backward moving direction, even in the presence of the disturbances in the dynamics. In reference regulation mode, a sliding mode heading direction controller is used such that the actual robot can maintain the desired posture against the disturbances. In this way, robust posture stabilization can be achieved at almost all global regions.

• Journal of Oral Medicine and Pain
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• v.20 no.2
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• pp.489-496
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• 1995

The purpose of this study was to evaluate an effect of change on head posture initial occlusal contacts with measuring the distances between initial occlusal contacts and maximum intercuspal position at different head posture in TMDs patient. For this study, 24 patients from age 13 to 36 were selected, they were examined health history taken, patients who have sign and symptoms of TMDs were examine before the study. For the normal group, 21 adults from age 23 to 25 were selected. They have normal or class I molar relationship, and have no other prosthetic restorations. Difference on distance between initial occlusal contact and maximum intercuspal position with mandibular kinesiograph$(MKG^R)$(K6 diagnostic system, Myo-tronic Inc, USA) in upright, supine, 45$^{\circ}$ extension, 30$^{\circ}$ flexion position of the head were measured. The Frankfort horizontal plane was used as a reference plane. The results were as follows : 1. There were significant differences between initial occlusal contacts of the normal and patient group on upright position and 30$^{\circ}$ flexion of the head(p<0.05, p<0.01) 2. The position of the initial occlusal contacts have a tendency to place anterior and inferior to maximal intercuspal position in upright position and 30( flexion of the head as well as posterior and inferior in supine position and 45$^{\circ}$ extension of the head in the normal and patient groups. 3. There were significant differences among the initial occlusal contacts between uptight and supine position; upright and 45$^{\circ}$ extension of the head(p<0.05); supine position and 30$^{\circ}$ flexion of the head, .and 30(flexion and 45$^{\circ}$ extension of the head in the patient group(p<0.01) The result have shown that after treatment on the supine position, it may be necessary to check occlusal contact on the upright position as well ass flexion of the head. It may need careful adjustment in occlusal condition on upright position of TMDs patient.

• Journal of Korean Institute of Industrial Engineers
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• v.29 no.4
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• pp.271-282
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• 2003

Automotive occupant packaging has been a part of main ergonomics interests, especially, in terms of driver's posture. Previous research on driver's posture has mainly focused on the initial optimal posture for driving sedans. However, customer preferences on cars are shifting from sedans to RV and automobile manufacturing companies seek to understand temporal changes in drivers' posture according to driving environment. So the main aim of this study was to develop a driver's posture measurement system during driving and investigate casual changes due to duration, car type, traffic flow. Four male drivers participated in the experiments during one week. It was shown that considerable changes in their postures were caused with respect to driving environment, which implies that not only static optimal postures but their dynamic changes should be taken into consideration for proper design and evaluation of interior packaging. The research is expected to help packaging designers understand human drivers so as to improve their comfort.

• The Journal of Pediatrics of Korean Medicine
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• v.38 no.2
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• pp.32-40
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• 2024

Objectives The main aim was to quantify forward head posture using POM Checker®, a postural balance analyzer, among elementary school students. Additionally, the study aimed to investigate whether postural imbalance improved following three sessions of the school doctor program focused on body posture correction. Methods The program was conducted as part of the school doctor program in Korean Medicine, featuring lectures by a designated Korean Medicine doctor at an elementary school. The curriculum covered the importance of maintaining correct posture and included posture correction exercises. Pre- and post-program self-reported surveys were administered, alongside postural measurements taken over three months at one-month intervals. The survey included data on gender, grade, lifestyle habits, and awareness of correct posture. Result Out of 73 participating students, 63 underwent body balance measurements from the upper grades of one elementary school. Survey results revealed significant variations in daily sitting hours and weekly exercise levels. Attendance at lectures increased knowledge about correct posture. Initial measurements of forward head posture categorized 41.0% and 1.6% of participants into caution and risk groups, respectively. After the second measurement, the caution group representation decreased to 3.2%, and by the third measurement, only 1.6% of participants remained in the caution group. Conclusions Improvements in the angle and understanding of forward head posture among elementary school students were observed before and after the Korean Medicine school doctor program. However, posture improvement may be temporary, necessitating consistent follow-up management and monitoring.

• Physical Therapy Korea
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• v.21 no.1
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• pp.37-46
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• 2014

Asymmetric sitting posture may cause asymmetric buttock pressure and unilateral low back pain (LBP). The purpose of this study was to compare the differences of buttock pressure between both sides, and pelvic angle (sagittal and coronal planes) during typing in a sitting position on a pressure mat (Baltube) in individuals with and without unilateral LBP. Ten subjects with unilateral LBP and ten subjects without unilateral LBP were recruited for this study. Buttock pressure was measured using a pressure mat and pelvic angles were measured using a palpation meter. The subjects performed typing in a sitting posture for 30 minutes. Pressure data were collected and averaged at initial term (from start to first minutes) and final term (last minutes of 30 minutes). Angles of pelvic tilting were measured after 30 minutes typing. Pressure asymmetry values (difference in pressure between both sides) were calculated at the initial and final terms. A two-way analysis of variance was used to compare the differences between the initial and final pressure asymmetry values in subjects with and without unilateral LBP. An independent t-test was applied to compare the pelvic tilt angles between the two groups. To compare the change of pressure from the initial term to the final term between the symptomatic and asymptomatic sides in the unilateral LBP group, a paired t-test was applied. In the unilateral LBP group, the pressure asymmetric value at the final term was significantly greater than that of the initial term (p<.05). The angle of pelvic tilting in coronal plane was significantly greater in the unilateral back pain group compared to the without unilateral LBP group (p<.05), however, there was no significant difference in the angle of pelvic tilting in the sagittal plane between the two groups (p>.05). In the unilateral LBP group, the change of pressure from the initial term to the final term was significantly less in the symptomatic side (-6.90 mmHg) than the asymptomatic side (5.10 mmHg). This asymmetric sitting posture may contribute to unilateral LBP in the sitting position. Further studies are needed to determine if asymmetric weight bearing in sitting causes unilateral LBP or if unilateral back pain causes asymmetric weight bearing, and if the correction of asymmetric weight bearing in sitting can reduce unilateral LBP.