• CELLMED
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• v.3 no.2
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• pp.13.1-13.6
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• 2013

The objective of the current study was to find out the effect of Integrated Amrita Meditation Technique (IAM) on blood pressure (BP), heart rate (HR), respiratory rate (RR) and IgA. One hundred and fifty subjects were randomized into three groups IAM, Progressive Muscle Relaxation (PMR) and Control. Baseline values were collected before giving the training for all the subjects and the IAM and PMR groups were given training in the respective techniques. BP, HR, RR and IgA were recorded manually at 0 h, 48 h, 2 months and 8 months after the first visit. HR was found to be reduced in the IAM group 48 h onwards and the fall sustained till 8 months (p < 0.05). IAM group showed significant drop when compared to the PMR group and control group in all the subsequent visits (p < 0.05). RR decreased significantly in the IAM group in the third and fourth visits (p < 0.05). RR of IAM showed significant decrease when compared to PMR and control from the third visit onwards. IgA showed significant increase in comparison with PMR and control in the third and fourth visits. BP did not show any difference in any of the visits. There was subject dropout from randomization to completion of the study, in all the three groups. The significant decrease in HR and RR and increase in IgA in the IAM group when compared to the PMR and control group shows the efficacy of the technique in reducing the physiological stress indicators for up to 8 months.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.9
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• pp.175-181
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• 2019

In the case of a conventional single stage decompression regulator used for large depressurization in the hydrogen fuel cell system of a fuel cell electric vehicle (FCEV), problems can arise, such as pulsation, slow response, hydrogen brittleness, leakage, high weight, and high cost due to high decompression. Most of these problems can be overcome easily using two decompression mechanisms (two-stage structures). In addition, a wide outlet-pressure control range can be secured if an electronic solenoid is applied to the second decompression. Accordingly, it is necessary to improve the precision of the outlet pressure of a two-stage pressure-reducing regulator and develop techniques, such as leakage prevention, durability, light weight, and price reduction. Therefore, to improve the outlet pressure accuracy and prevent leakage, the structural part before and after decompression to improve the air tightness were divided and the analysis was carried out assuming that the valve part was closed (open ratio: 0%) after each initial internal pressure application.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.21 no.2
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• pp.329-340
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• 1997

A passive control of interaction of condensation shock wave / boundary layer for reducing the strength of condensation shock was conducted experimentally in a 2.5 * 8 cm$^{2}$ indraft type supersonic wind tunnel. The effects of following factors on passive control were investigated: 1) the thickness of porous wall, 2) the diameter of porous hole, and 3) the orientation of porous hole. On the other hand, the location of nonequilibrium condensation region and condensation shock wave was controlled by regulation of the stagnation conditions. Surface static pressure measurements as well as Schlieren observations of the flow field were obtained, and their effects were compared with the results the cases of without passive control. It was found that thinner porous wall, smaller porous hole and FFH orientation for the same cavity size and porosity of 12% are more favourable than the cases of its opposite.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.21 no.6
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• pp.506-513
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• 2011

This paper is concerned with a study on the control effect of the MR damper using the cutout piston. The MR damper has passive damping force by the oil pressure and controllable damping force by the magnetic effect. As the velocity of the MR damper's piston increases the passive damping force increases and the ratio of the controllable damping force to the total damping force is decreased. Consequently, the control performance of the MR damper is reduced according to the increase of the velocity. In this paper, the cutout piston concept is applied to the MR damper to improve MR damper's control performance by reducing the passive damping effect. The MR damper with the cutout piston has been designed and manufactured and its hydraulic and electromagnetic analysis has been performed to predict its performance. The control performances of the MR damper with the cutout piston are verified through the comparison of experiment results and simulation results.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2002.10a
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• pp.1066-1069
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• 2002

Dynamic postural control varies with the environmental context, specific task and intentions of the subject. In this paper, dynamic postural control against forward-backward perturbations of a platform was estimated using tri-axial accelerometers and a force plate. Ten young healthy volunteers stood upright in comfortable condition on the perturbation system which was controlled by an AC servo motor. With anterior-posterior perturbations, movements of ankle, knee and hip Joints were obtained by tri-axial accelerometers. and ground reaction forces with corresponding displacements of the center of pressure(CoP) by the force plate. The result showed that the ankle moved first and the trunk forward, which implies that the mechanism of the dynamic postural control in forward-backward perturbations, occurred in the procedure of the ankle, the knee and the hip. Knee flexion and hip extension in the period of acceleration, constant velocity and deceleration phase is very important fur the balance recovery. These responses depends on the magnitude and timing of the perturbation. From the present study the accelerometry-system appears to be a promising tool for understanding kinematic accelerative In response to a transient platform perturbation. A more through understanding of balance recovery mechanism may aid in designing methods for reducing falls and the resulting injuries.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.24 no.1
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• pp.62-68
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• 2014

Recently, MRI(magnetic resonance imager) scanner is continually used for medical diagnosis and many biomedical researches. When it operates, however, intense noise is generated. The SPL(sound pressure level) of the noise approaches 130 dB especially in 3 T(Tesla) MRI. Meanwhile, more than 3 T MRI scanners have been developed to get higher-resolution images, so louder noise is expected in the future. The intense noise makes patients feel nervous and uncomfortable. Moreover, it could possibly cause hearing loss to patient in extreme cases. For this reason, some active noise control systems have been researched. One of them used feedback Filtered-X LMS(FXLMS) algorithm which is able to control only narrowband noises and possible to diverge in severe case. In this paper, we determine the property of MRI noise. Using the property, we applied a method of open-loop and adaptive control for reducing MRI noise at target point inside bore. We verified performance of the method with computer simulation and preliminary experiment. The results demonstrate that the method can effectively reduce MRI noise at target point.

• Plant Journal
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• v.11 no.2
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• pp.45-51
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• 2015

In this paper, studied condenser operating management which is affecting power plants efficiency considering the cost of poor quality. Sea water temperature and condenser pressure have clear correlation in S power plants. As the sea water temperature changes, condenser pressure changed -1.7~+20 mmHg from design condenser pressure(38.1 mmHg). Use the heat rate correction curve from manufactory company, realized that efficiency and cost of poor quality changed 0.0201%, 12,830 won/h at Unit #1,2 but 0.0155%, 9,832 won/h when condenser pressure 1 mmHg rise. Also, checked that it is changed depend on seasonal corresponding operation, plant ageing and the point of preventive maintenance like overhaul maintenance. This study said if we considered complying with management range and planning overhaul maintenance, then it could help reducing operating maintenance losses minimum 2.5 billion won per 1 year (case : Unit #1, forty days maintenance).

• Korean Journal of Veterinary Research
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• v.60 no.3
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• pp.105-108
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• 2020

These days abattoirs' hygiene of Korea is regulated by Hazzard Analysis Critical Control Point (HACCP). Although 20 years have been left since first HACCP was adjusted in Korea, 12% of abattoirs got inconsistence on evaluations. Food poisoning caused by bacteria feces like pathogenic Escherichia coli and Salmonella has not decreased. These bacteria on meat cross-contaminate at the abattoir. Therefore, field verification of abattoir's critical control point (CCP) and experiments to find alternative ways of the CCP were conducted. The aerobic bacteria were measured before and after high-pressure water based washing process set as CCP in most abattoirs. Four parts of cattle carcasses were selected to apply sponge-swab method. The effects were < 1 log reduction which is not significant. Lactic acid (LC), chlorine dioxide (ClO₂) and slightly acidic electrolyzed water (SAEW) were used to measure the effect of reducing bacteria on beef by the different time. LC has 1.24-2.02 log reduction for aerobic bacteria. ClO₂ has 1.44-1.96 log reduction for aerobic bacteria. SAEW has 1.1-1.91 log reduction for aerobic bacteria. There was significant difference according to concentrations (p < 0.05). This study presents legitimacy for hygiene improvement of CCP by field verification. In addition, chemical disinfectants that can be mechanically applied have better reduction effects of high-pressure washing.

• Journal of Korean Physical Therapy Science
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• v.28 no.1
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• pp.46-53
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• 2021

Background: The purpose of this study was to investigate the effect of taping applied to the lower trapezius on the upper trapezius muscle tone, pain intensity, cervical rotation range of motion in chronic upper trapezius pain patients. Design: Case-control study. Methods: Twenty subjects with chronic upper trapezius pain were classified into an experimental group and a control group. The experimental group applied lower trapezius facilitation taping and the control group applied sham taping. Taping Before and after the application of taping, muscle tone, pain intensity, and cervical rotation range of motion of the upper trapezius were measured. Results: In the experimental group, there were significant differences in the pressure pain threshold and muscle tone before and after taping. In the comparison between groups, there was a significant difference in muscle tone between the experimental group and the control group. Conclusion: The application of the lower trapezius facilitation taping was found to be effective in reducing the pressure threshold and muscle tone of the upper trapezius. Therefore, it is expected that more effective treatment can be provided by adding lower trapezius facilitation taping to the treatment protocol for patients with chronic shoulder pain.

• Journal of the Korean Society for Precision Engineering
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• v.16 no.1 s.94
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• pp.42-48
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• 1999

A control method for a robot hand grasping a object in a partially unknown environment will be proposed, where a proximate sensor detecting the distance between the fingertip and object was used. Particularly, the finger joints were driven servo-pneumatically in this study. Based on the proximate sensor signal the finger motion controller could plan the grasping process divided in three phases ; fast aproach, slow transitional contact and contact force control. That is, the fingertip approached to the object with full speed, until the output signal of the proximate sensor began to change. Within the perating range of the proximate sensor, the finger joint was moved by a state-variable feedback position controller in order to obtain a smooth contact with the object. The contact force of fingertip was then controlled using the blocked-line pressure sensitivity of the flow control servovalve for finger joint control. In this way, the grasping impact could be reduced without reducing the object approaching speed. The performance of the proposed grasping method was experimentally compared with that of a open loop-controlled one.