• Journal of Institute of Control, Robotics and Systems
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• v.15 no.7
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• pp.694-699
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• 2009

This paper presents the implementation of the real-time object tracking control of the ROBOKER head. The visual servoing technique is used to track the moving object, but suffers from ill-estimated Jacobian of the virtual link design. To improve the tracking performance, the RBF(Radial Basis Function) network is used to compensate for uncertainties in the kinematics of the robot head in on-line fashion. The reference compensation technique is employed as a neural network control scheme. Performances of three schemes, the kinematic based scheme, the Jacobian based scheme, and the neural network compensation scheme are verified by experimental studies. The neural compensation scheme performs best.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2004.05a
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• pp.888-893
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• 2004

This paper proposed a dual actuator using bimorph PZT for information storage device based on prove array NSOM(Near-field Scanning Optical Microscopy). The gap between the media and the optical head should be maintained within the optical tolerance. Therefore, a new actuator having high sensitivity is required. Bimorph PZT, which has fast access time and high sensitivity characteristic, is suitable for this precise actuating system. This paper is focused on derivation of mathematical model of dual bimorph PZT actuator and control algorithm. Hamilton's principle was used for mathematical model. The model is verified by FEA(Finite Element Analysis), and compared with experimental results. Different control algorithms were used f3r two bimorph PZT actuating same direction and opposite direction. The gap between recording media and optical head was controlled within 20nm in experiment.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2004.11a
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• pp.586-591
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• 2004

A load/unload mechanism is applied to most small form factor hard disk drives. Loading velocity is ones of the most important factors to ensure the reliability of the load/unload operations. Especially, the lower the flying height of the head becomes, the more important the accuracy of the loading velocity control becomes. Because there is no sensor during the load/unload operations, BEMF voltage is used to sense the head velocity. To measure BEMF voltage, a simple circuit is added to the load/unload HDD control system. Overall acceptable results are obtained by using the simple PI controller but the errors from the target velocity occur when the head moves along the ramp and then reaches the disk. Feedforward profile and disturbance observer are used to remove those errors effectively.

• Child Health Nursing Research
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• v.8 no.2
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• pp.204-216
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• 2002

The purpose of this study was to investigate the effect of massage therapy on weight gain, length and head circumference in instituted infants. This study utilized nonequivalent control group with repeated measuring by quasi experimental design. Fifty eight instituted infants in Daejeon city were selected for the study. Fifty eight infants were randomly assigned two groups, one served as the control group and the other was experimental group to whom massage therapy was given. For the experimental group, massage protocol(developed by Field, 1986) was applied 2 times a day, mid-morning and early evening, for 4 weeks for each infants by researcher and trained research assistants. As a weight weighing instrument, electronic indicator scale (Cas Co., Korea) was used. The result of this study were summarized as follows; 1.A repeated measures ANOVA identified a significant group by time effect over the four weeks of intervention(F=14.69, p < .0001). Infants assigned to experimental group gained more weight than control group infants. 2. T-test identified that significant differences in length(t=2.60, P=.013) and head circumference(t=4.27, P=.000). Infants assigned to experimental group had more length and head circumference than control group infants. In conclusion, Massage therapy improved weight gain, length and head circumference of instituted infants. Therefore, it is recommended to utilize massage therapy as a nursing intervention for instituted infants.

• The Journal of Korean Physical Therapy
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• v.24 no.2
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• pp.163-169
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• 2012

Purpose: The present study was designed to investigate the effect of trunk control training on the labile surface on relative impulse and balance in stroke patients. Methods: A total of 21 participants were assigned to an experimental group (n=11) or a control group (n=10). In addition to conventional therapy, the experimental group received trunk control training on the swiss ball; 20 minutes, 4 times a week, for 8 weeks. Balance ability was evaluated by FRT (functional reaching test) and TUG (time up and go). In addition relative impulse in 6 areas of the foot (hallux, 1st metatarsal head, 2~3 metatasal head, 4~5 metatasal head, mid foot and heel) were measured using the F-scan system to evaluate locomotion ability during gait. Results: Significant differences in the relative impulse were observed in the areas of the 2~3 metatasal head during gait after exercise in both the control group and experimental group (p<0.05). Also, a significant increase was seen in the hallux after exercise in the experimental group (p<0.05), but no such significant increase was seen in the control group (p>0.05). Significant differences were observed in FRT and TUG in the experimental group but no such significant increase was observed in the control group (p>0.05). Conclusion: These results suggest that trunk control training on labile surface improves the balance in stroke patients and has a positive effect on locomotion ability.

• The Journal of Korean Academy of Orthopedic Manual Physical Therapy
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• v.25 no.2
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• pp.57-64
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• 2019

Background: This study was designed to identify the effect of the taping on the forward head posture during computer work. Methods: Twenty healthy adults were statistically assigned into 2 groups, the taping group (n=10) and the control group (n=10). In order to induce delayed onset muscle soreness (DOMS), twenty subjects performed isometric exercise of the neck on Bobath table for 20 minutes. During the experiment, subjects in taping group were attached Kinesio-tape on their upper trapezius. By using 2-D motion analysis, measurements were taken before taping, at 24 hour, 48 hour, and 72 hour after inducing DOMS. The effects of taping were evaluated by the angle of the head. Results: The results of this study were as follows; 1) There was no significant difference between the taping group and the control group (p>.05). 2) The control group had no significance, but the taping group shown a significance on the angle of head during computer work (p<.01). The interaction of group x period also shown a significance (p<.01). Conclusion: From these result, it was revealed that the taping therapy on upper trapezius could improve the angle of head during computer work.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.41 no.5
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• pp.357-365
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• 2013

In this study, forces and moments were measured on a projectile which consisted of a missile configuration body(shell) and a head installed control fins. The shell and the head were separated each other and the shell was rotated by an electric motor. The head rotated reversely against the rotational direction of the shell. The rotational force on the head was obtained from a couple of fixed fins of which angular displacement were set to the rotational direction equally. The air velocity was 40m/s on the experiment and the Reynolds number based on the diameter of head was $1.3{\times}10^5$. The other couple of fins were used to control the position and direction of the projectile by changing the angular displacement. From this experiment, the variation of force and moment were measured on the rotating projectile, and the effective amplitude and frequency were obtained through the FFT analysis.

• Korean Journal of Head & Neck Oncology
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• v.10 no.2
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• pp.102-105
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• 1994

The indolent course of most thyroid papillary carcinomas, even the presence of regional lymph node metastasis, make them unique among human malignant head and neck cancers. Age, sex, extracapsular invasion and anaplastic change are known to be correlated with prognosis. The purpose of this study is to clarify the significance of DNA content analysis as a prognostic factor. Twenty five thyroid papillary carcinomas were possible to be examined by flow cytometric analysis using fresh surgical specimens and three nodular hyperplasias and seven follicular adenomas were included as control group. The results were as follows: l) All of twenty five thyroid papillary carcinomas showed diploidy. 2) S-phase fraction was $1.94{\pm}2.77%$ in normal control group and $2.60{\pm}2.66%$ in papillary carcinoma group. The proliferation index was $8.44{\pm}3.89%$ in normal control and $7.70{\pm}3.63%$ in papillary carcinoma group with even low value. 3) Age, sex, extracapsular spread and lymph node metastasis showed no significant difference. In conclusion, low proliferative activity of thyroid papillary carcinomas are thought to be related with good prognosis.

• Journal of Clinical Otolaryngology Head and Neck Surgery
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• v.29 no.2
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• pp.182-189
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• 2018

Background and Objectives : There were few literatures about the relationship between upper airway disorders and cardiovascular risk factors such as hypertension, although an association between impaired lower respiratory function and cardiovascular alterations was often reported. Our purpose was to assess the relationships between chronic sinusitis and hypertension. Materials and Methods : Three hundred subjects with bilateral chronic sinusitis who underwent functional endoscopic sinus surgery between 2015and 2017 were evaluated. Six hundred forty subjects without any nasal diseases were enrolled as a control group. Blood pressure and body mass index (BMI) were measured using a standardized method, and subjects were asked about current use of any antihypertensive medication, history of diabetes, smoking and alcohol drinking habits.Sinusitis group was assessed by nasal endoscopic examination, paranasal sinus CT scan and allergy test. Results : Average systolic and diastolic blood pressures were statistically significantly higher in subjects with sinusitis than control group. Chronic rhinosinusitis was associated with a 1.415-fold (95% confidence interval 1.053-1.930) increased hazard of hypertension after multivariate adjustment. Conclusions : These results suggest that sinusitis is associated with high blood pressure. Therefore patients with sinusitis may need special attention for blood pressure control. Further studies need to be performed to elucidate the pathogenesis behind such associations.

• The Journal of Korean Academy of Orthopedic Manual Physical Therapy
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• v.28 no.3
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• pp.41-49
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• 2022

Background: In patients with forward head posture (FHP), the head is positioned forward, causing increased tension in the muscles and structures of the head, neck, and shoulders. This can result in joint dysfunction that may lead to abnormal afferent information. The purpose of this study was to investigate the effect on foot pressure through the isometric hip abduction (IHA) bridge exercise using elastic bands in patients with FHP. Methods: Twenty patients with FHP were randomly assigned to a study group that applied joint mobilization, soft tissue mobilization, a deep neck flexor strengthening exercise, and the IHA bridge exercise using an elastic band. A control group was also constituted, and members were given joint mobilization, soft tissue mobilization therapies, and the deep neck flexor strengthening exercise. Ten patients were assigned to each group. The static foot pressure and dynamic foot pressure of each patient were measured before and after the intervention, and the interventions for each group were applied twice a week for 4 weeks. Results: Both the study group and the control group showed significant differences in static and dynamic foot pressure before and after the interventions (p<.05). There were no significant differences in foot pressure between the study and control groups. Conclusion: : The results of this study revealed that there were no significant differences between the group doing the IHA bridge exercise using the elastic band and the control group. However, the intervention methods applied to both the groups were effective in improving the body center control of FHP patients.