• Korean Journal of Applied Biomechanics
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• v.13 no.2
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• pp.1-12
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• 2003

This study was performed to provide normative isokinetic strength of knee muscles of middle school non-athletic and athletic populations for rehabilitation and pre-season screening for injury prevention. Seven non-athletic subjects and 8 hockey players participated in this investigation. Each subject was tested at speeds of $60^{\circ}/sec$, $180^{\circ}/sec$, and $300^{\circ}/sec$. The free weight of lower leg was measured at speed of $60^{\circ}/sec$ to take gravity effect Into consideration when peak torque of knee muscles occurred. The results showed that the relative peak torque production of knee flexors did not change but the relative peak torque of knee extensors decreased significantly. Mamstring/quadriceps ratios increased mainly due to significant decreases in knee extensors torque production. No significant differences were found between groups. The hamstring/quadriceps ratios for both groups were significantly lower when the gravity effect was not eliminated.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.52 no.4
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• pp.339-346
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• 2016

The aim of this research was to the experimental data using statistical and spectral analyzing method to get the motion reponses of a stern trawler in operation states such as drifting, sailing and trawling according to the wave height. In drifting, the significant and the maximum valuer of roll in beam sea increased according to the wave height, but those of pitch decreased. The response and the period of peak of roll in beam sea were increased, but those of pitch decreased. In navigation, the significant and maximum values of roll increased remarkably according to the wave height, but those of pitch changed a little. The response of roll was highest in quartering sea, beam sea and then following sea, but those of pitch was highest in bow sea, head sea and then beam sea in the order of all wave heights. The period of peak of roll due to the wave height and the wave direction changed from 3.8 to 9.9 seconds, and those of pitch changed from 3.3 to 10.4 seconds. In trawling, the significant and maximum values of roll increased a little according to the wave height, but those of pitch increased significantly. The response of roll was highest in beam sea, bow sea and then quartering sea, but those of pitch was highest in head sea, following sea, and then beam sea in the order. The period of peak of roll due to the wave height and the direction changed from 6.6 to 10.9 seconds, and those of pitch changed from 6.7 to 11.2 seconds.

• Korean Journal of Applied Biomechanics
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• v.28 no.3
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• pp.159-164
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• 2018

Objective: The aims of this study were to determine the impact peak force and kinematic variables in running speed and investigate the relationship between them. Method: Thirty-nine male heel strike runners ($mean\;age=21.7{\pm}1.6y$, $mean\;mass=72.5{\pm}8.7kg$, $mean\;height=176.6{\pm}6.1cm$) were recruited in this investigation. The impact peak forces during treadmill running were assessed, and the kinematic variables were computed using three-dimensional data collected using eight infrared cameras (Oqus 300, Qualisys, Sweden). One-way analysis of variance ANOVAwas used to investigate the influence of the running speed on the parameters, and Pearson's partial correlation was used to investigate the relationship between the impact peak force and kinematic variables. Results: The running speed affected the impact peak force, stride length, stride frequency, and kinematic variables during the stride phase and the foot angle at heel contact; however, it did not affect the ankle and knee joint angles in the sagittal plane at heel contact. No significant correlation was noted between the impact peak force and kinematic variables in constantrunning speed. Conclusion: Increasing ankle and knee joint angles at heel contact may not be related to the mechanism behind reducing the impact peak force during treadmill running at constant speed.

• Journal of Oral Medicine and Pain
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• v.25 no.1
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• pp.87-97
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• 2000

This study was performed to investigate the effects of repetitive mandibular opening movement and change of head posture on the vibration of temporomandibular(TM) joint. For this study, 23 patients with internal derangement of TM joint were selected. All they had clinically noticeable TM joint sound. Observation of the joint vibration were performed in four head postures, namely, natural head posture (NHP), forward head posture(FHP), upward head posture(UHP), and downward head posture(DHP). For recording of joint sound vibration, Sonopak of Biopak system(Bioresearch Inc., Milwaukee, USA) was used, The author could take results related to integral higher than 300Hz, integral lower than 300Hz, ratio of integral higher than 300Hz to integral lower than 300Hz, total integral which was sum of higher and lower integral, peak amplitude, and peak frequency in each opening movement, which was carried out three times in each head posture. Integral means amount of vibration. The data obtained were analysed by SPSS windows program and the results of this study were as follows : 1. In NHP, total integral in right TM joint was 5O.3Hz in the first opening, 67.9Hz in the second opening, and 74.0Hz in the third opening movement, bur there was no significant increase of total integral with repetitive opening movement. This finding was similar in left TM joint. Integral lower than 300Hz were higher than integral higher than 300Hz in almost every opening movement. 2. There was no significant difference of total integral between right and left side of TM joint, but there was a tendency of higher total integral in right TM joint than that in left TM joint except for results in DHP. 3. Peak amplitude in NHP ranged from 2.0 to 4.7, and peak frequency in NHP were 101.4-170.0Hz. And there was no consistent findings related to increase or decrease of these value according to repetitive opening in each head posture. 4. Change of head posture did not result any difference in integral, peak amplitude, and peak frequency. In conclusion, change of head posture and repetitive mandibular opening movement did not make any significant effect on the vibration of temporo-mandibular joint, especially, on total integral, peak amplitude, and peak frequency.

• Journal of Sasang Constitutional Medicine
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• v.18 no.2
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• pp.68-82
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• 2006

1. Objectives and Methods The purpose of this study was to objectify the diagnosis of Sasang constitution. It was analyzed the adult men and women's [i] sound into 23 factors with PSSC-2004. The study was conducted by subjects inputting 2.5-3 sec of [i] of 586 adult men and women's voices to PSSC-2004. The statistical analysis are applied to three groups : total group, male group, female group. The group of total 586 was composed with 155 Soyangin, 230 Taeumin and 201 Soeumin. The male group was composed with 61 Soyangin, 127 Taeumin and 87 Soeumin. The female group was composed with 94 Soyangin, 103 Taeumin and 114 Soeumin. 2. Results (1) In total group, the Soyangin's code3 was significantly low compared with the others(P=0.011). In total group, the Taeumin's code2 and the Soyangin's code1 were significantly high compared with the others(p=0.007)(P=0.030). (2) In total group, the Soyangin's peak, 50 up in peak and under 3 in peak were significantly low compared with the others(P=0.003) (P=0.005)(P=0.023). (3) In total group, the Taeumin's rank7, rank8, rank9 and rank10 were significantly high compared with the others (P=0.013)(P=0.015) (P=0.016)(P=0.003). (4) In male group, the Soeumin's code3 was significantly high compared with the others(P=0.002). (5) In male group, the Soeumin's peak sum was significantly high compared with the others(P=0.009). It was significant for distinction between Soeumin and Soyangin at the result of post mortem. In male group, the Soeumin's 50 up in peak, 50 down in peak were significantly high compared with the others(P=0.049)(p=0.037). In male group, the Soeumin's under 3 in peak was significantly high compared with the others(P=0.016). It was significant for distinction between Soeumin and Soyangin at the result of post mortem. (6) In male group, the Soeumin's rank 2, rank 3 and rank 4 were significantly low compared with the others(P=0.011) (0.011)(0.024). (7) In female group, the Taeumin's code2 was significantly high compared with the others(P=0.023). In female group, the Soyangin's code1 was significantly low compared with the others (P=0.046). In female group, Soyangin's code-1 was significantly high compared with the others(P=0.024). It was significant for distinction between Taeumin and Soyangin at the result of post mortem. (8) In female group, the Taeumin's peak sum was significantly high compared with the others(P=0.024). It was significant for distinction between Taeumin and Soyangin at the result of post mortem. In female group, the Taeumin's 50 up in peak was significantly high compared with the others(P=0.012). (9) In female group, the Taeumin's rank 7, rank 8, rank 9 and rank 10 were significantly high compared with the others (P=0.009) (P=0.013)(P=0.016)(P=0.023). 3. Conclusion From above result, there is the possibility of efficiency standardguide for constitutional diagnosis by analyzation of the voices.

• Proceedings of the Korea Electromagnetic Engineering Society Conference
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• 2005.11a
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• pp.69-74
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• 2005

The High Peak to Average Power Ratio (PAPR) could be a severe Problem in OFDM performance since it causes the significant distortion to the transmitting signal through a nonlinear device such as High Power Amplifier (HPA). In this paper, the performance of Peak cancellation method according to the HPA characteristic is comparatively analyzed with the clipping and windowing methods. The BER performances and the out-band power spectrums are demonstrated in detail.

• Journal of the Korean Society of Physical Medicine
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• v.6 no.4
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• pp.407-414
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• 2011

Purpose : The aim of this study was to clarify the lung capacity, maximal insufflation capacity, and peak cough flow when a mechanical insufflation-exsufflation(MIE) method was used to increase Duchenne muscular dystrophy patients' lung function. Methods : The subjects of the study were 21 patients with Duchenne muscular dystrophy. They were randomly selected from patients within the boundaries of the selection criteria, and divided into two groups; The subject group(n=11) used the mechanical insufflation-exsufflation method with traditional therapeutic exercise. The control group(n=10) used only traditional therapeutic exercise. Results :The results indicated that maximal insufflation capacity, unassisted peak cough flow and assisted peak cough flow significantly increased in the subject group(p<.05). By contrast, in the control group, the results didn't indicate the significant differences from the variable. There were significant differences in maximal insufflation capacity and assisted peak cough flow between the subject group and the control group before and after the application of the mechanical insufflation-exsufflation method. Conclusion : A mechanical insufflation-exsufflation method has positive effects on the improvements of cough functions and that of pulmonary functions such as lung volume, lung elasticity in patients with Duchenne muscular dystrophy.

• Structural Engineering and Mechanics
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• v.27 no.4
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• pp.425-438
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• 2007

Large changes in stiffness associated with cracking and yielding of reinforced concrete sections may be expected to occur during the dynamic response of reinforced concrete frames to earthquake ground shaking. These changes in stiffness in stories that experience cracking might be expected to cause relatively large peak interstory drift ratios. If so, accounting for such changes would add complexity to seismic design procedures. This study evaluates changes in an index parameter to establish whether this effect is significant. The index, known as the coefficient of distortion (COD), is defined as the ratio of peak interstory drift ratio and peak roof drift ratio. The sensitivity of the COD is evaluated statistically for five- and nine-story reinforced concrete frames having either uniform story heights or a tall first story. A suite of ten ground motion records was used; this suite was scaled to five intensity levels to cause varied degrees of damage to the concrete frame elements. Ground motion intensity was found to cause relatively small changes in mean CODs; the changes were most pronounced for changes in suite scale factor from 0.5 to 1 and from 1 to 4. While these changes were statistically significant in several cases, the magnitude of the change was sufficiently small that values of COD may be suggested for use in preliminary design that are independent of shaking intensity. Consequently, design limits on interstory drift ratio may be implemented by limiting the peak roof drift in preliminary design.

• Korean Journal of Applied Biomechanics
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• v.17 no.4
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• pp.45-55
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• 2007

We investigated the biomechanics and characteristics of shoulder rotator muscles for professional woman volleyball players. The purpose of this study was to analyze the isokinetic peak torque and range of motion for shoulder joint rotation. We measured the strength and ROM of the internal rotation(IR) and external rotation(ER) of shoulders joint for nine professional woman Volleyball players and nine University students with Biodex and Simi-motion. 1. We measured peak torques for the shoulder joint rotator at angular velocities of 60/s and 180/s. It was found that the peak torques were significantly different between the two groups and also between the hands used. 2. At angular velocity of 60/s, IR/ER ratio of the shoulder joint was significantly different depending on the groups and the hands in use. There was a significant difference for 'Dominant side' at angular velocity of 180/s, but no significant difference for 'Non-dominant side' and the controls group. 3. Regarding the ROM of rotation of the shoulder joint group, IR was significantly different between the groups and the hands in use. 4. IR/ER ratio of the shoulder joint for Dominant side was quite different between the groups.

• Physical Therapy Rehabilitation Science
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• v.12 no.2
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• pp.130-139
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• 2023

Objective: This study aimed to analyze the effects and characteristics of the height of the treatment table on the force and time of ground reaction (GR) and contact hand (CH) generated from the therapist's feet to generate thrust during spinal manipulation (SM). Design: A cross-sectional survey study Methods: Thirty-six healthy subjects were recruited. SM was performed on the ilium using a knee-high table, where the therapist felt it was easy to control the subject's posture and body shape and comfortable to generate force, as well as a relatively high thigh-high table. The force and time generated by the therapist's GR and CH were simultaneously measured through a force plate. Results: As a result, there was a significant difference in peak force and rundown force at the therapist's GR according to the table height (p < 0.05). In the therapist's CH, there was a significant difference between PreMin (preload minimum) force and peak force (p < 0.05), and there was a significant difference between the time from PreMin to peak and the time of the entire section (p < 0.05). Conclusions: As a result, the generation of increased CH force and faster thrust duration were confirmed by mobilizing the reduced GR force of the therapist to generate thrust than the relatively high table on the knee-high table.