• Journal of Institute of Control, Robotics and Systems
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• v.21 no.5
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• pp.401-406
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• 2015

In this study, the gait imbalance evaluation algorithm based on two axes angle using encoder is proposed. This experiment was carried out to experiment with a healthy adult male to 10 people. The device is attached to the hip and knee joint in order to measure the angle during the gait. Normal and imbalance gait angle data were measured using an encoder attached to the hip and knee joints. Also, in order to verify the reliability of estimation of asymmetrical gait using hip and knee angle, it was compared with the result of asymmetrical gait estimation using foot pressure. SI (Symmetry Index) was used as an index for determining the gait imbalance. As a result, normal gait and 1.5cm imbalance gait were evaluation as normal gait through SI using an encoder. And imbalance gait of 3cm, 4cm, and 6cm were judge by imbalance gait. Whereas all gait experiments except normal gait were evaluation as imbalance gait through SI using the pressure. It was possible to determine both the normal gait and imbalance gait through measurement for the angle and the pressure.

• Journal of Convergence for Information Technology
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• v.11 no.3
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• pp.250-260
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• 2021

The purpose of this study is to investigate muscle function and symmetry index during whole body vibration exercise using lower extremity training posture for throwing athletes. For throwing athletes in their 20s(6 males, 4 females, age: 24.60±0.92years, height: 177.90±7.40cm, weight: 92.90±22.97kg), lower extremity training postures with squat, carphrase, and lunge movements. Whole body vibration exercise training was performed using. Tensiomyography(TMG) variables Time Delay(Td), Time Contraction(Tc), Time Sustain(Ts) Time Relaxation(Tr), and Displacement Maximumal(Dm) in the lower extremity joint muscles(biceps femoris(BF), gastrocnemius lateral(GL), gastrocnemius medial(GM), rectus femoris(RF), tibialis anterior(TA), lateral vastus(LV), medial latissimus(ML)), were measured to compare and analyze muscle activity, muscle fatigue, and left-right symmetry. The results of the study are left RF, VL, right VM (p<.05) in Td, VM (p<.05) in Tc, GM in Ts (p<.05), left RF in Tr, and right TA (p<. 05) showed a change. Therefore, it has been proven that various whole-body vibration training is an effective exercise with changes in muscle contraction, and stability of the core is secured by symmetry of the left and right muscles. For this reason, the whole body vibration exercise will have a positive effect on rehabilitation training, and it is believed that it will be able to improve performance.

• Journal of Integrative Natural Science
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• v.13 no.1
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• pp.19-26
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• 2020

In this paper, we study on the reinterpretation of Burnside's theorem that is a tool to compute the number of equivalence classes of a group action on a set, and by applying it, we find out the numbers of different patterns in coloring problems of various types of figures with symmetry and use them for computing the numbers of different kinds of chemical compounds.

• Korean Journal of Optics and Photonics
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• v.28 no.1
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• pp.33-38
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• 2017

The universality of the quasi-linear relation between the order parameter S and the normalized birefringence ${\Delta}n_{rel}$, $S=(1+a){\Delta}n_{rel}-a{\Delta}n^2_{rel}$ is confirmed. It is verified that the refractive index of liquid crystals distributed with regular polyhedral symmetry is isotropic and it is given as $\frac{1}{n^2_{av}}=\frac{1}{3}\(\frac{1}{n^2_e}+\frac{2}{n^2_o}\){\cdot}S$ and ${\Delta}n_{rel}$ of angular weighted liquid crystals that are initially distributed with regular polyhedral symmetry, are numerically calculated. Also ${\Delta}n_{rel}$ and S of liquid crystals that are conically distributed, keeping the rotational symmetry about z-axis are calculated as the apex angle of the cone is varied. Based on these calculated results, it is confirmed that the quasi-linear relation between S and ${\Delta}n_{rel}$ is universal, independent of the details of the distribution function.

• The Journal of Korean Physical Therapy
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• v.35 no.5
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• pp.145-150
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• 2023

Purpose: This study examined the effects of ankle control training using neuromuscular electrical stimulation (NMES), leg muscle activation, and balance in stroke patients. Methods: Thirty-one stroke patients diagnosed with cerebral infarction and cerebral hemorrhage were selected for the study. The experimental group underwent ankle control training using NMES, while the control group applied NMES to the paretic tibialis anterior muscle for 30 minutes per session, five times a week for four weeks. The muscle activity changes were measured using surface electromyography, and balance parameters were evaluated using a functional reach test (FRT). Results: The intra-group comparison of the concentric muscle activity revealed improvements in the experimental group, including paretic tibialis anterior (TA) muscle (p<0.05), medial gastrocnemius muscle (MG) (p<0.01), and lateral gastrocnemius muscle (LG) (p<0.05), as well as MG (p<0.05), LG (p<0.05), soleus muscle (p<0.05) of the non-paretic side, and soleus muscle symmetry index (p<0.05). The intra-group comparison of the eccentric muscle activity showed improvements in the experimental group, including MG (p<0.01) and LG (p<0.01) of the paretic side, as well as MG (p<0.01), LG (p<0.01) of the non-paretic side, and LG symmetry index (p<0.01). The intra-group comparison of the functional reach test revealed significant differences in the test results in the experimental and control groups (p<0.05). Conclusion: Ankle control training using NMES had a positive effect on the changes in muscle activation and improved balance in patients with stroke.

• Animal cells and systems
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• v.2 no.4
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• pp.507-511
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• 1998

Fingerprints of 100 New Zealand-Samoan males and 93 females have been analyzed. Whorls are more numerous in fingerprint females (65.6%) than in males (55.6%). The index of pattern intensity displays a higher value in females (16.49) than in males (15.48). The bimanual differences both in males and females are not statistically significant for the occurrence of patterns on the digits of the right and left hands. Also the difference between both sexes for the occurrence of patterns is not statistically significant. Incidences of actual symmetry on homologous digits represented 78.2% in males and 85.8% in females. The mean total ridge counts showed $175.7{\pm}54.6$ ($M{\pm}SD$) in males and $171.6\{pm}49.8$ ($M{\pm}SD$) in females, respectively. Conclusively, this study shows that the New Zealand-Samoans are closely related to the Mongoloids in quantitative dermatoglyphics.

• Proceedings of the Korean Society of Marine Engineers Conference
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• 2005.06a
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• pp.1022-1028
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• 2005

This paper is presented the analysis results and simulation results of cascaded H-bridge 7 level inverter with various modulation index. Stepped waveform having number of switching was used to eliminate harmonic components. Switching angles according to modulation index are calculated numerically. Therefore, 3 times of switching with 7 level topology and QWS(Quarter Wave Symmetry) could eliminate 5th and 7th harmonics. The harmonic characteristics are compared to those of space vector modulation method which known as common modulation method in industrial field. Stepped waveform method showed higher ability to reduce, especially lower order of harmonics.

• Animal cells and systems
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• v.4 no.1
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• pp.91-94
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• 2000

Fingerprints of 114 Australian Aboriginal males and 90 females have been analyzed. Whorls are more frequent in males (56.7%) than in females (51.2%) and loops are less frequent in males (42.6%) than in females (47.0%). The index of pattern intensity displays a higher value in males (15.60) than in females (14.94). The bimanual differences both in males and females ave not statistically significant for the occurrence of patterns on the digits of the right and left hands. Also the difference between both sexes for the occurrence of patterns is not statistically significant. Incidences of actual symmetry on homologous digits represented 74.0% in males and 77.3% in females. The mean total ridge counts showed 156.65 $\pm$43.32 (M$\pmSD) in males and 148.6943.64 (M$\pmSD) in females, respectively. Conclusively, this study represents that the Australian Aborigines conform closely to the Polynesians in finger dermatoglyphics.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.18 no.11
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• pp.1048-1055
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• 2005

The formula to calculate a variation of optical path length of single crystal by the electric field was derived by this study. The formula was applied to $Bi_{12}SiO_{20}$ single crystal. The results are as follows. In case of the applied electric field in the body diagonal direction and the passing light along the same direction, the variation of optical path length had the largest value. The symmetry of the space distribution of optical path length satisfied $E3C_2\;8C_3$, the set of elements of the symmetry of $Bi_{12}SiO_{20}$ single crystal. The property which gave the largest influence to the variation of optical path length is the strain of length by the Inverse piezoelectric effect. The second influence, is the variation of the refractive index by the electro-optic effect. The variation of optical path length by the inverse piezoelectric effect and by the electro-optic effect have a reverse sign each other.

• Journal of rehabilitation welfare engineering & assistive technology
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• v.10 no.2
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• pp.147-153
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• 2016

The aims of this study were to evaluate the joint coordination between hip and knee joints in the transfemoral amputees, and its symmetry between sound and prosthetic limbs. Seven transfemoral amputees ($46.4{\pm}10.7-year-old$, $174.8{\pm}3.5cm$, $78.3{\pm}9.7kg$) and 7 able bodies ($24.0{\pm}4.5-year-old$, $174.5{\pm}5.9cm$, $66.9{\pm}9.4Kg$) participated in this study. They walked at a self-selected walking speed across a 10m level ground. Simultaneously angle and angular velocity in the hip and knee joint were measured by motion analysis system. Then continuos relative phase(CRP), standard deviations of CRP (CRP_SD) and symmetry index(SI) were calculated. In able bodies, there were no differences of the parameters between left and right limb(all p>0.05). However, significant differences between sound and prosthetic limb in most of the parameters, except for CRP for stance phase were shown (all p<0.05). There were differences in all SI between transfemoral amputees and able bodies (p<0.05). In conclusion, joint coordination was altered in transfemoral amputee during level walking and shown in interlimb asymmetry.