• Archives of Craniofacial Surgery
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• v.16 no.2
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• pp.49-52
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• 2015

The alveolar cleft has not received as much attention as labial or palatal clefts, and the management of this cleft remains controversial. The management of alveolar cleft is varied, according to the timing of operation, surgical approach, and the choice of graft material. Gingivoperiosteoplasty does not yet have a clear concensus among surgeons. Primary bone graft is associated with maxillary retrusion, and because of this, secondary bone graft is the most widely adopted. However, a number of surgeons employ presurgical palatal appliance prior to primary alveolar bone graft and have found ways to minimize flap dissection, which is reported to decrease the rate of facial growth attenuation and crossbite. In this article, the authors wish to review the literature regarding various advantages and disadvantages of these approaches.

• Journal of Power Electronics
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• v.16 no.2
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• pp.399-413
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• 2016

This paper presents a topology for a modular power electronic transformer (PET) and a control scheme. The proposed PET consists of a cascaded H-Bridge rectifier on the primary side, a high-frequency DC/DC conversion cell in the center, and a cascaded H-Bridge inverter on the secondary side. It is practical to use PETs in power systems to reduce the cost, weight and size. A detailed analysis of the structure is carried out by using equivalent circuit. An algorithm to control the voltages of each capacitor and to maintain the power flow in the PET is established. The merits are analyzed and verified in theory, including the bi-directional power flow, variable voltage/frequency and high power factor on the primary side. The experimental results validated the propose structure and algorithm.

• Archives of Craniofacial Surgery
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• v.12 no.2
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• pp.102-106
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• 2011

Purpose: It is accepted universally that correction of the cleft lip nasal deformity requires multiple stages of surgery. Following primary lip repair in infancy or early childhood, secondary surgery to improve the deformity of the lip and nose is frequently necessary. A suitable surgical procedure to correct the accompanying deformity, such as cleft palate and alveolus, must be carried out at an appropriate age. In developing countries, it is common for patients with cleft lip nasal deformity to present severe secondary deformities in adolescence, because of poor follow-up and inappropriate surgery. Methods: The first patient was a 12 year old Mongolian boy. He presented prominent lip scar, short lip, wide columella, asymmetric nostril, palatal fistula, cleft alveolus, and velopharyngeal incompetence. He underwent cheilorhinoplasty, transpositional flap, alveoloplasty by iliac bone graft, and sphincter pharyngoplasty. On follow-up, a bilateral maxillary hypoplasia and a class III malocclusion developed. He underwent LeFort I osteotomy and maxillary advancement at the age of 16 years. The second patient was an 18 year old Eastern Russian girl. She presented with a deviated nose, right alar base depression, short lip, protrusion on vermilion, large palatal fistula, and severe VPI due to short palate. She underwent the combined procedure of cheilorhinoplasty, corrective rhinoplasty, tongue flap for palatal fistula, and superiorly based pharyngeal flap. And the tongue flap was detached at postoperative 3 weeks. Results: The overall results have been extremely pleasing and satisfactory to patients. There were no postoperative complications. Conclusion: We discovered the one stage operation for radical correction was sufficient procedure to provide excellent clinical outcomes in patients with severe cleft lip nose deformity.

• Korean Journal of Cleft Lip And Palate
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• v.4 no.2
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• pp.69-78
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• 2001

Alveolar cleft exists in 75% of cleft patients, In alveolar cleft patients, alar base is widening, palatal fistular formation, maxillary growth disturbance & tooth loss of adjacent area is raised, Alveolar bone grafting, especially iliac bone grafting, is a general treatment method. As operation timing, bone grafting is classified with primary, early secondary, secondary, & late secondary, Here we report cleft width, marginal bone height, bone resorption rate, grafted shape & bone densities after secondary iliac bone grafting was done in the Dept. of oral and maxillofacial surgery of chonbuk national university hospital. We compared cleft width to bone resorption rate and grafted shape. Also, alveolar bone densities of grafted and contralateral site was compared with Emago 3 package? (Oral Diagonostic System, The Netherlands), The data obtained were analyzed using Spearman's rho coefficients and sign test with SPSS for window, The results were obtained as follows. 1. As alveolar cleft width is increase, bone resorption rate is, too. This relation showed significant difference(P<.01). 2, In proximal & distal area, alvolar cleft width and bone graft contour after bone grafting had a reverse proportional difference. It was not significant difference(P>.05). 3. After 3 month, in bone density results by using Emago 3 package? with periapical standard view, occlusal view & panoramic view, differences between grafted bone and alveolar bone of contralateral site didn't show a significant difference(P>.05). Thus, differences of bone densities in the alveolar bones didn't exist.

• Journal of Internet Computing and Services
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• v.24 no.6
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• pp.57-64
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• 2023

This study analyzed the perceptions of elementary and secondary school teachers regarding the importance of SW/AI education in fostering students' fundamental knowledge and the necessity of integrating SW/AI into education. A total of 830 elementary and secondary school teachers were selected as study subjects using the judgment sampling method. The analysis of survey data revealed that elementary and secondary teachers exhibited a strong awareness of the importance and necessity of SW/AI education, irrespective of school characteristics, region, educational experience, or prior involvement in SW and AI education. Nevertheless, the primary reasons for not implementing SW/AI education were identified as excessive workload and a lack of pedagogical expertise. An analysis of opinions on the essential conditions for implementing SW/AI education revealed that workload reduction, budget support, teacher training to enhance teacher competency, content distribution, expansion of subject-linked courses, and dedicated instructional time allocation were the major influencing factors. These findings indicate a significant demand for comprehensive instructional support and teacher capacity-building programs.

• Proceedings of the KIEE Conference
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• 1996.07a
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• pp.486-488
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• 1996

A dc-dc converter which transfers l2-48W of power(regulated output voltage 24V) across a large, variable air gap(1-2cm) has been designed. This converter employs double resonance to compensate the large leakage inductance of the primary and secondary of the transcutaneous transformer. To maximize the effect of resonance, a constant frequency, duty cycle control method is used. The duty cycle control presents advantages over a frequency control in terms of increase in dc voltage gain and reduction of the primary current. The analysis and design procedure for the proposed scheme is presented and the performance result is simulated and verified experimentally.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2011.10a
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• pp.672-672
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• 2011

This study describes the comparison of noise suppression performances at different locations of two error microphones in active noise control (ANC) for outdoor applications. For this study, 12 different locations were predefined to decide best locations for error sensors in terms of suppressing noise. As shown in Fig. 1, the ANC system with one primary loudspeaker, two secondary loudspeakers and two error microphones is operated by a filtered-x LMS (FXLMS) algorithm which is implemented in a TI 6713 DSP board and Realsys 4713 AD/DA Extension board. The noise for the primary source is a typical road noise measured at a highway roadside. The lengths of adaptive filters of W1 and W2 are varied from 32 to 128 respectively. An intensive computer simulation was accomplished before outdoor ANC experiments. It is expected from the simulation results that the ANC performances are very much dependent upon the locations of the two error microphones.

• Journal of the Korean neurological association
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• v.36 no.4
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• pp.294-301
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• 2018

Background: Neuroimaging can play a crucial role in discovering potential abnormalities to cause secondary headache. There has been a progress in the fields of headache diagnosis and neuroimaging in the past two decades. We sought to investigate neuroimaging findings according to headache disorders, age, sex, and imaging modalities in first-visit headache patients. Methods: We used data of consecutive first-visit headache patients from 9 university and 2 general referral hospitals. The International Classification of Headache Disorders, third edition, beta version was used in headache diagnosis. We finally enrolled 1,080 patients undertook neuroimaging in this study. Results: Among 1,080 patients (mean age: $47.7{\pm}14.3$, female: 60.8%), proportions of headache diagnosis were as follows: primary headaches, n=926 (85.7%); secondary headaches, n=110 (10.2%); and cranial neuropathies and other headaches, n=43 (4.1%). Of them, 591 patients (54.7%) received magnetic resonance imaging (MRI). Neuroimaging abnormalities were found in 232 patients (21.5%), and their proportions were higher in older age groups and male sex. Chronic cerebral ischemia was the most common finding (n=88, 8.1%), whereas 76 patients (7.0%) were found to have clinically significant abnormalities such as primary brain tumor, cancer metastasis, and headache-relevant cerebrovascular disease. Patients underwent MRI were four times more likely to have neuroimaging abnormalities than those underwent computed tomography (33.3% vs. 7.2%, p<0.001). Conclusions: In this study, the findings of neuroimaging differed according to headache disorders, age, sex, and imaging modalities. MRI can be a preferable neuroimaging modality to identify potential causes of headache.

• Tuberculosis and Respiratory Diseases
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• v.61 no.5
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• pp.490-495
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• 2006

Leiomyoma of the bronchus is a very rare benign tumor of the lung. Most endobronchial leiomyomas occur as secondary foci of primary uterine leiomyoma. We herein report a case with endobronchial tumor that had a different pathology from a primary resected uterine leiomyoma and was therefor considered a primary endobronchial leiomyoma. A 51-year-old woman with a history of uterine myoma presented with productive cough and fever. Bronchoscopy revealed a lightly yellow colored mass lesion that totally obstructed the orifice of the left lower lobe of the lung. The diagnosis of leiomyoma was made by histological examination of the obtained specimen. We considered the possibility of a benign metastasizing pulmonary leiomyoma. For treatment and differential diagnosis, a left lower lobe lobectomy of the lung and total hysterectomy with bilateral salphingooopherectomy were performed. The differences between lung and uterine lesions were confirmed by morphologic finding and immunohistochemical staining. The pathological diagnosis was primary endobronchial leiomyoma combined with uterine myoma.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.13 no.3
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• pp.39-45
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• 2013

In this paper, we propose a cooperative relaying protocol using Fountain codes for secondary network under interference constraint. In the proposed protocol, a secondary source uses Fountain codes to transmit its message to a secondary destination with help of a secondary relay. The secondary source and relay operate in the underlay model, in which they must adapt their transmit power so that the interference caused at a primary user is lower than an allowable threshold. To evaluate performance of the proposed protocol, we derive the expressions of average number of transmission times over Rayleigh fading channel. Various Monte-Carlo simulations are presented to verify the derivations.