• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.38 no.3
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• pp.177-183
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• 2012

Herpes zoster is a viral infection caused by the reactivation of the varicella zoster virus, an infection most commonly affecting the thoracolumbar trunk. Herpes Zoster Infection (HZI) may affect the cranial nerves, most frequently the trigeminal. HZI of the trigeminal nerve distribution network manifests as multiple, painful vesicular eruptions of the skin and mucosa which are innervated by the infected nerves. Oral vesicles usually appear after the skin manifestations. The vesicles rupture and coalesce, leaving mucosal erosions without subsequent scarring in most cases. The worst complication of HZI is post-herpetic neuralgia; other complications include facial scarring, motor nerve palsy and optic neuropathy. Osteonecrosis with spontaneous exfoliation of the teeth is an uncommon complication associated with HZI of the trigeminal nerve. We report several cases of osteomyelitis appearing on the mandible, caused by HZI, and triggering osteonecrosis or spontaneous tooth exfoliation.

• Journal of Korean Physical Therapy Science
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• v.5 no.3
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• pp.651-658
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• 1998

Cerebral palsy is a neurodevelopmental impairment caused by a nonprogressive defect or lesion in single or multiple locations in the immature brain. The defect or lesion can occur in utero or during or shortly after birth and produces sensory-motor impairment that are usually evident in early infancy. The causes of cerebral palsy are not completely understood, certain prenatal, perinatal, and postnatal factors have been associated with cerebral palsy. This study was analysed the clinical features of 50 children with cerebral palsy (29 males and 21 females) in National Rehabilitation Hospital from March 17 to June 27, 1998. The time of initial visit was over than 12 months in 74%, and their cheif complains were delayed developments (78%). The preterm infants were 40% and the infants with low birth weight were 36%. The maternal age at childbirth was over than 30 years old in 52%. The most common type of cerebral palsy was spastic (54%), mixed (22%), athetosis and hypotonia (10% each), ataxia (4%). The cerebral palsy with preterm infants and low birth weight were more likely to have spastic type (P=0.002, P=0.023 each). The most preterm infants were born between 30 and 35 years old of maternal age, and there were statistical significance in difference (P=0.031).

• Journal of Korea Society of Digital Industry and Information Management
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• v.13 no.3
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• pp.11-17
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• 2017

The aerial support air sculptures currently exhibited in indoor spaces are similar to simple ad balloons, using multiple rope strands. Users now want more advanced unfixed sculptures, and hope these will develop into buoyant sculptures that can maintain the attitudes that users want on their own. This study investigated an attitude control system for unfixed levitation sculptures that can levitate with no rope and continuously maintain a certain attitude at a height specified by the user. To facilitate levitation, the exterior part of the sculpture was made of lightweight fibers, and the interior part was filled with helium gas. The controller was composed of a microprocessor of the dsPIC30F line from microchip, gyro, acceleration, and earth magnetic field sensors, and a highly efficient brushless DC (BLDC) electric motor. The attitude and position control system requires scheduling considering the trajectories of the sculpture and the control system, because the roles of the overall components are more important than those of a single controller. Furthermore, the system was designed like a fusion system that is expanded and controlled as a total controller, because it is interconnected with various sensors. The attitude control system of buoyant sculptures was implemented in this study, such that it can actively cope with the position, direction, stopping, and time aspects. The system performance was then evaluated.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.21 no.2
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• pp.534-540
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• 1996

This paper presents an Adaptive Time-Delay Recurrent Neural Network (ATRN) for learning and recognition of temporal correlations of temporal patterns. The ATRN employs adaptive time-delays and recurrent connections, which are inspired from neurobiology. In the ATRN, the adaptive time-delays make the ATRN choose the optimal values of time-delays for the temporal location of the important information in the input parrerns, and the recurrent connections enable the network to encode and integrate temporal information of sequences which have arbitrary interval time and arbitrary length of temporal context. The ATRN described in this paper, ATNN proposed by Lin, and TDNN introduced by Waibel were simulated and applied to the chaotic time series preditcion of Mackey-Glass delay-differential equation. The simulation results show that the normalized mean square error (NMSE) of ATRN is 0.0026, while the NMSE values of ATNN and TDNN are 0.014, 0.0117, respectively, and in temporal learning, employing recurrent links in the network is more effective than putting multiple time-delays into the neurons. The best performance is attained bythe ATRN. This ATRN will be sell applicable for temporally continuous domains, such as speech recognition, moving object recognition, motor control, and time-series prediction.

• Journal of the Korean Society for Precision Engineering
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• v.31 no.6
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• pp.543-550
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• 2014

A magnet gear composed of two layers of permanent magnets repeated circumferentially can transmit the power without mechanical contact. In the topology called by the magnet shutter gear known as the most competitive concept among the existing concepts, the number of pole-pairs on the high speed rotor corresponds to that of low speed rotor through electric steel set functioning as a magnetic modulator. The methodology is classified into radial type and axial type according to its magnetic path as in the motor. However, the magnetic modulator has multiple poles located separately. So, it is very complicated to assemble each module of the magnet gear mechanically and to sustain a mechanical stiffness of the modulator. The practical trouble can be solved partially through reconfiguring the modules. This paper deals with the novel magnetic shutter gear topology varying the magnetic path and its effectiveness is verified through real hardware implementation.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.25 no.6
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• pp.317-323
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• 2013

A multi-perforated tube indicates the existence of multiple holes of various shapes on the surface of a long cylinder-type or rectangular tube, and a hole installed on the surface is called an orifice, as it is relatively small in size, compared with the surface area of the tube. In this study, the flow characteristics of a circular multi-perforated tube with many orifices on the surface were investigated experimentally and numerically. The volume flowrate issuing from each orifice, discharge angle, effective flow area ratio, and the flow fields around the orifices were measured and visualized, with the variation of the orifice area ratio, at the same blockage ratio. The volume flowrate distributions along the flow direction of the multi-perforated tube tends to be more uniform, as larger orifices were positioned at the inlet side of the multi-perforated tube, compared with no orifice area change along the flow direction.

• Journal of Trauma and Injury
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• v.20 no.1
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• pp.47-51
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• 2007

Penetrating chest trauma caused by the components of one's own car is rare in motor vehicle accidents. We experienced two cases of penetrating chest injury caused by the sideview mirror of the patient's vehicle. One was a 25-year-old man. The sideview mirror penetrated the left chest, went through the diaphragm, and ruptured the spleen. He was in shock upon arrival at the emergency room. An emergency thoracotomy and laparotomy were done. The ruptured spleen was resected, the lung and the diaphragm were debrided and repaired, and the chest wall was reconstructed. The other patient was a 57-year-old male, who was transported to our emergency room with the sideview mirror of his truck stuck into his right chest wall as the result of an accident. He also had a right Bennet's fracture and an open fracture of the right tibia. Air had been sucked into the right pleural cavity through the wound. Multiple rib fractures and lung lacerations had also occurred. Removal of the sideview mirror, repair of the lacerated lung, and reconstruction of chest wall were done immediately. Both patients recovered without complication and were discharged.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2013.10a
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• pp.525-530
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• 2013

With the increasing the importance of emotional quality of vehicle, the sound quality of systems with electric motor components has become increasingly important. Electric motors are used for windows, seats, sun roof, mirrors, steering columns, windshield wiper, climate control blowers, etc. In this paper, a study was conducted to identify sound quality factors that contribute to customer's satisfaction and preference of the window lift system. Jury test for subjective evaluation was carried out and sound quality index was developed. Averaged sound pressure level and sharpness were significant factors when glass moves down. Also, maximum loudness at stop section and averaged loudness were significant factor when glass moves up. Noise source identification was carried out for the reduced the loudness and sharpness during glass transferred section and impulsive noise at stop section, Using the source identification result, several improvement points were applied. And finally, the degree of sound quality improvement was judged using sound quality index.

• Parasites, Hosts and Diseases
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• v.38 no.3
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• pp.167-171
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• 2000

We report a chronic cerebral paragonimiasis from a 41-year-old Korean man who complains a headache and weakness of left motor neuron components. Magnetic resonance images of the brain revealed conglomerates of multiple ring-like enhancements in tempore-occipital and frontal lobes of the right hemisphere. An intradermal test for paragonimiasis westermani was positive. The patient was born near an endemic area of paragonimiasis and used to eat boiled or grilled freshwater crayfish in his childhood. Nodules in the brain were resected through craniotomies. The eggs of P. westemani were identified pathologically and parasitologically in the calcified necrotic lesions. Examinations on sputum and fecal specimens for the eggs of P. westemani were shown to be negative and a chest radiograph was normal. It is presumed that the brain lesions were formed by P. westemani approximately 30 years ago.

• Journal of Korean Neurosurgical Society
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• v.29 no.3
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• pp.396-401
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• 2000

We report a case of spontaneous cervical epidural hematoma caused by a pure epidural arteriovenous malformation. A 22-year-old woman developed a sudden quadriplegia after a vigourous physical therapy including multiple acupunctures for her neck pain. Emergency cervical magnetic resonance image showed an epidural hematoma in her cervicothoracic junction. Emergent decompressive laminectomy and an evacuation of the hematoma were performed. A soft tissue mass found in the hematoma was proven to be an arteriovenous malformation. Postoperatively, the patient experienced some complications. However, she recovered completely from the motor weakness.