• Journal of the Korean Society of Physical Medicine
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• v.15 no.3
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• pp.51-59
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• 2020

PURPOSE: The purpose of this study was to provide clinical basic data to reduce pain and improve function by comparing neck muscle activity and neck alignment using self-stretching and passive stretching exercises for chronic neck pain caused by forward head posture. METHODS: The subjects were divided into 15 subjects assigned to perform self-stretching exercise and 15 subjects assigned to perform passive stretching exercise. The intervention was conducted for a total of 4 weeks. The muscle activity in the neck was measured by surface electromyography (EMG) before intervention, and craniovertebral and cranial rotation angles were measured by X-ray. The 4-week intervention was conducted and the above items re-measured in the same manner and analyzed. RESULTS: Muscle activity within both groups after intervention using self-stretching or passive stretching exercise was significantly different (p < .05)(p < .01). Neck alignment of both groups was significantly different (p < .001)(p < .01). Further, muscle activities of the upper trapezius and splenius capitis muscles showed significant differences (p<.05). Lastly, neck alignment showed statistically significant difference (p < .05). CONCLUSION: Self-stretching exercise activated motor nerves as a posture correction exercise, thereby improving inhibition of muscle activity, muscle contraction delay, and pathological conditions of the muscle. For future research, interventions of self-stretching exercise will be needed for patients with chronic back pain accompanied by forward head posture, and various clinical studies on postural improvement of forward head posture by maintaining a normal muscle tone state are needed.

• Clinics in Shoulder and Elbow
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• v.21 no.1
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• pp.42-47
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• 2018

A 25-year-old woman presented to the emergency room with a painful and swollen right forearm. She had just sustained an injury from an accident during which her arm was tightly wound by a rope as she was lowering a net from a fishing boat. Before being released, her arm was rigidly trapped in the rope for approximately ten minutes. Radiographs revealed anterior dislocation of the radial head that was accompanied by plastic deformation of the proximal ulna, manifested as a reversal of the proximal dorsal angulation of the ulna (PUDA); suggested a Monteggia equivalent fracture. With the patient under general anesthesia, we reduced the radial head by posterior compression at $90^{\circ}$ of elbow flexion and at neutral rotation of the forearm. However, the reduction was easily lost and the elbow re-dislocated with even slight supination or extension of the arm. After the osteotomy of the ulnar deformity to restore the PUDA to normal, the reduction remained stable even with manipulation of the arm. We found that the patient could exercise a full range of motion without pain at the 3-month follow-up, and neither residual instability nor degenerative changes were observed at the final 3-year follow-up.

• Journal of the Korean Society of Physical Medicine
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• v.10 no.2
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• pp.17-27
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• 2015

PURPOSE: The purpose of this study was to compare the effects of three interventions (intervention by passive range of motion exercise plus manual cervical traction, Mulligan's joint mobilization, and strengthening exercises) after Kaltenborn's joint mobilization on the cervical spine alignment, and muscle activity in patients with a forward head posture. METHODS: The subjects were 39 students from H University in Chungnam and C University in Jeonbuk. The subjects in each group attended training sessions three times a week for four weeks. We used one-way ANOVA and Scheffe's post hoc test to compare values between groups, and used paired t-test to compare the values of the dependent variables within groups. RESULTS: The results showed that the active intervention group experienced a significant increase compared to the passive intervention group in terms of the craniovertebral angle, cervical lordosis angle, and had significant decreases compared to the passive intervention group in terms of the upper trapezius muscle activity. The active intervention group also had significant increases in craniovertebral angle and decreased anterior scalene muscle activity than the active-assistive intervention group. The active-assistive intervention group had significant decreases compared to the active intervention group in terms of the serratus anterior, levator scapulae, and splenius capitis muscle activity. CONCLUSION: It appears that the subjects with a forward head posture had significant improvements in the cervical lordosis angle, cranial rotation angle, craniovertebral angle, and muscle activity after intervention by Mulligan's joint mobilization (active-assistive intervention component) and strengthening exercises (active intervention component) after applying Kaltenborn's joint mobilization.

• Journal of Wetlands Research
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• v.22 no.2
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• pp.121-129
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• 2020

This paper described a laboratory investigation of micro hydropower at lower head water in a free vortex flow. The vortex height, turbine rotation and torque for straight blade with inner curved edge, twisted blade and curved blade were investigated at the flow rate of 0.0069 ㎥/s in the inlet channel. The results showed that the optimum vortex strength occurred within the range of the diameter of basin to the outlet diameter ratios of 0.17~18.5. The power output and efficiency of straight blade were higher as compared to other blades. The highest amount of generated energy was 12.33 W, the torque was 0.91 N·m and the highest efficiency by considering effective head was 29.5 %, whereas the highest efficiency by considering vortex height was 80.5 % at the rotational speed of 132 rpm. The water vortex velocity of straight blade was about 2.8 times larger than the mean velocity in the inlet channel.

• The KIPS Transactions:PartC
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• v.17C no.3
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• pp.291-298
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• 2010

In wireless sensor networks, energy is the most important consideration because the lifetime of the sensor node is limited by battery. The clustering is the one of methods used to manage network energy consumption efficiently and LEACH(Low-Energy Adaptive Clustering Hierarchy) is one of the most famous clustering algorithms. LEACH utilizes randomized rotation of cluster-head to evenly distribute the energy load among the sensor nodes in the network. The random selection method of cluster-head does not guarantee the number of cluster-heads produced in each round to be equal to expected optimal value. And, the cluster head in a high-density cluster has an overload condition. In this paper, we proposed both a token based cluster-head selection algorithm for guarantee the number of cluster-heads and a cluster selection algorithm for uniform-density cluster. Through simulation, it is shown that the proposed algorithm improve the network lifetime about 9.3% better than LEACH.

• The korean journal of orthodontics
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• v.31 no.3 s.86
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• pp.311-323
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• 2001

One of the various mechanics used to treat unilateral Class II malocclusion is head gear with asymmetric face bow. We made the finite element models of unilateral Class II maxillary dental arch and power arm asymmetric face bow. We designed this experiment to observe stress distribution of periodontal ligament, reaction force, and displacement and to understand force system, so to predict the therapeutic effect. On the basis of computerized tomograph of maxillary dental arch of 25 years old male with normal occlusion without extraction and orthodontic treatment history, we made finite element models of maxillary dental arch and periodontal ligament. Then we modified that model to unilateral maxillary Class II malocclusion model of which maxillary left molar displaced mesially. Also, We made finite element model of asymmetric face bow of which right outer bow shorter than left by 25mm(RMO, Penta-FormTM/Medium size, 0.045 inch iner bow, 0.072 inch outer bow). After that, retraction force of 250g, 300b, 350g were applied to maxillary first molar. We concluded as follow. 1. The Net force that both maxillary first molars were received increased as the retraction force increased. Mesially positioned tooth received more force than normally positioned tooth. But, both tooth were received distal force, so distal movement occured. 2. Both tooth received buccal lateral force. In analysis of force element, as the retraction force were increased, force of X-axis at mesially positioned tooth decreased, and force of X-axis at normally positioned tooth increased. so lateral force component moved to the side received less force from more force. 3. There were rotation, tipping with distal movement in maxillary first molar. As retraction force were increased, rotation and tipping also increased. More tipping and rotation occured at the side received more force, that is, mesially positioned tooth. Though it Is small change, displacement of same pattern occur in normally positioned tooth

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.40 no.6
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• pp.31-40
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• 2003

Most face recognition systems are based on 2D images and applied in many applications. However, it is difficult to recognize a face when the pose varies severely. Therefore, head pose estimation is an inevitable procedure to improve recognition rate when a face is not frontal. In this paper, we propose a novel head pose estimation algorithm for 3D face recognition. Given the 3D range image of an unknown face as an input, we automatically extract facial feature points based on the face curvature. We propose an Error Compensated Singular Value Decomposition (EC-SVD) method based on the extracted facial feature points. We obtain the initial rotation angle based on the SVD method, and perform a refinement procedure to compensate for remained errors. The proposed algorithm is performed by exploiting the extracted facial features in the normaized 3D face space. In addition, we propose a 3D nearest neighbor classifier in order to select face candidates for 3D face recognition. From simulation results, we proved the efficiency and validity of the proposed algorithm.

• Korean Journal of Otorhinolaryngology-Head and Neck Surgery
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• v.61 no.11
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• pp.580-587
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• 2018

Background and Objectives We evaluated the clinical characteristics and vestibular function of patients with direction changing vibration induced nystagmus (DC VIN) and unilateral vestibular hypofunction and suggest clinical implication and a proposed mechanism of DC VIN. Subjects and Method The records of 315 patients who underwent the VIN test were reviewed retrospectively. Among these, 18 patients (5.7%) showed DC VIN, and out of whom, 15 patients (4.8%) were diagnosed as unilateral vestibular hypofunction by caloric, rotation chair (RCT), and video head impulse test (vHIT). We analyzed the relationship between DC VIN and the dizziness characteristics, duration of disease, and the outcome of the vestibular function test. Results The mean age of 15 patients was $67.4{\pm}10.7years$ and the mean duration of dizziness was $13.6{\pm}29.7months$. The caloric test revealed 25% of the patients to have significant canal paresis [Caloric vestibular neuritis (VN)], while 75% showed normal caloric response. However, unilateral vestibular hypofunction was observed by abnormal results in RCT or vHIT (Non-caloric VN). Seven patients showed ipsilateral DC VIN (nystagmus to vibrated side) and eight patients contralateral DC VIN (nystagmus to opposite side of vibration). Patients with ipsilateral DC VIN were shown to have a significant longer duration of dizziness than those with contralateral DC VIN. Conclusion Although rare, DC VIN can also be found in patients with unilateral vestibular hypofunction. Patients with DC VIN had a mild vestibular asymmetry with Non-caloric VN or Caloric VN in the process of compensation. The mechanism of ipsilateral DC VIN seems to be due to the small amount of vestibular asymmetry, which is smaller than the interaural attenuation of vibration.

• Journal of the Ergonomics Society of Korea
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• v.32 no.3
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• pp.245-252
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• 2013

Objective: This paper analyzes the changes on stride parameters, joint angles, and trajectories of the body parts due to high heels during walking and explains the causal relationship between the changes and high heels. Background: This study aims to indicate the comprehensive gait changes by high heels on the whole body for women wearing high heels and researchers interested in high-heeled walking. Method: The experiment was designed in which two different shoe heel heights were used for walking (1cm, 9.8cm), and twelve women participated in the test. In the experiment, 35 points on the body were tracked to extract the stride parameters, joint angles, and trajectories of the body parts. Results: Double support time increased, but stride length decreased in high-heeled walking. The knee inflexed more at stance phase and the spine rotation became more severe. The trajectories of the pelvis, the trunk and the head presented outstanding fluctuations in the vertical direction. Conclusion: The double support time and the spine rotation were changed to compensate instability by high heels. Reduced range of motion of the ankle joint influenced on the stride length, the knee flexion, and fluctuations of the body parts. Application: This study can provide an insight of the gait changes by high heels through the entire body.

• Research in Plant Disease
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• v.7 no.2
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• pp.69-79
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• 2001

Meloidogyne arenaria race 2 (59%) is widely distributed, followed by M. incognita race 1 (23%), and an unknown race of M. incognita (18 ％) in greenhouses in southern Korea. The key character to distinguish between M. arenaria and M. incognita is excretory pore in female head. When oriental melon, Cucumis melo L., grafted on Shintozoa (Cucurbit maxima x Cu. moschata) is transplanted in February in a plastic tunnel inside a greenhouse infested with M. arenaria, nematodes produced egg masses on roots at 40 days after transplanting and the soil juveniles (J2) population reach maximum in July to 3,817/100 ㎤. Juveniles are distributed relatively uniform over the 180-cm-wide row horizontally and the highest density occurs at 0-25 cm soil depth. For the control of root-knot nematodes, rice rotation, solarization, and soil addition treatments are the most effective (P=0.05); treatments reduce number of J2 over 90% and increase yield two times. Corn retation, fosthiazate, and soil drying treatment are moderately effective, while sesame and green onion rotations are not effective. The relationship between M. arenaria and yield of oriental melon is adequately described by a linear regression model. In the test with wild Cucumis genetic sources introduced from U.S.Dept. of Agriculture (USDA), one of C.heptadactylus, two of C.anguria, two of C. anguria var. longaculeatus, nine of C. metuliferus are resistant to both species of root-knot nematodes.