• Journal of Advanced Marine Engineering and Technology
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• v.38 no.3
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• pp.262-268
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• 2014

This research introduces the structural design and the validation results of the flexible high speed coupling for 2MW class wind turbine which transmit and cut off torque between gear box and generator. The high speed coupling requires electrical insulation to prevent electrical surface damages on gear box. Therefore glass fiber reinforced plastics is applied to absorb the vibration and deformation of power train and to transmit required torque. Finite element analysis was performed to optimize the thickness and accumulation number of glass fiber reinforced plastics. Torque limiter which cut off the abnormal torque is designed in frictional disc type. The design of the coupling was validated with the performance test of prototype.

• Radiation Oncology Journal
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• v.18 no.2
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• pp.85-91
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• 2000

Purpose : The aim of this study is to look for the possible efficacy of postoperative external irradiation for incompletely resected meningiomas. Methods and Materials : From August 198: to January 1997, forty-four patients with intracranial meningioma were treated by postoperative external irradiation. Of the 44 meningiomas, 18 transitional, 13 meningotheliomatous, 6 hemangiopericytic, 4 atypical, 2 fibroblastic and 1 malignant meningioma were identified. We classified all patients into two groups by the histology. The benign group was consisted of the meningotheliomatous, transitional and fibroblastic types. The malignant group was consisted of the atypical, hemangiopericytic and malignat types. In the means of surgery, 37 patients were resected incompletely and 7 patients were managed by biopsy only. After surgery, all patients were received postoperative external irradiation. Radiotherapy was deliverd using Co-60 or 4 MV photon beam to a total dose of 50 to 65 Gy (mean dose 57.4 Gy) with a 1.8 to 2 Gy per fraction. The median follow-up was 48 months (range : 21 $\~$ 101 months). Multivariate analysis of the Influence by age, sex, location, histology and radiation dose on local control has been done using Cox's proportional hazard model. Results : 5-year local control rate was 93.8$\%$ for the benign histology and 51.8$\%$ for the malignant histology (p=0.0110) and overall local control rate at 5 years was 87.4$\%$. The analysis of the prognostic factors, such as age, sex, location, and radiation dose were not significant except for the histology. Conclusion : Adjuvant postoperative external irradiation appears to be significantly improved local control in the patients with incompletely resected meningiomas.

• Journal of Korean Tunnelling and Underground Space Association
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• v.19 no.4
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• pp.651-668
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• 2017

For initial stability of the tunnel, the primary support, Shotcrete and rockbolt shall be placed in the most appropriate time. This is because the role of such support plays a vital role in long-term and short-term tunnel stability. In this study, the rock bolt is an important supporting system that receives the external pressure generated by the stress relaxation during tunnel excavation as axial force and transmits it to the shotcrete on the tunnel excavation surface. Until now, most of the materials of rock bolts have been used in the field, but there have been many problems such as uncertain quality of Chinese materials entering the market, poor packing due to falling down of rock bolts when filled with mortar, and corrosion due to water. Therefore, in this study, we have developed a high strength steel pipe rock bolt using Autobeam material to solve and improve various problems of existing rock bolts. In order to evaluate the performance of the developed bolt, field tests were carried out and the existing mortar filler in order to improve the performance of the rock bolt, the design and construction criteria were studied and the results were included in this paper.

• Korean Journal of Head & Neck Oncology
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• v.37 no.1
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• pp.57-61
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• 2021

Fibrous dysplasia is a bone condition characterized by the replacement of normal bone tissue and the medullary cavity by abnormal fibrous tissues. Craniofacial fibrous dysplasia causes facial asymmetry compromising the aesthetics as well as vision and hearing. A 21-year-old male visited the clinic due to vertical orbital dystopia and exophthalmos that had developed over the previous 2 months. The patient was diagnosed with a fibrous dysplasia of the frontal, ethmoid bones and superior orbital wall. By a bicoronal incision on the scalp, the radical resection of the lesions was done. After harvesting the remaining frontal bone, we did the autogenous reconstruction using split calvarial bone graft. Postoperatively, the vertical orbital dystopia and exophthalmos significantly improved. The patient is satisfied with the surgical outcomes and has not reported any recurrence.

• Composites Research
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• v.31 no.6
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• pp.385-391
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• 2018

In this study, carbon fibers were fabricated via carbonization of oxidized polyacrylonitrile (oxi-PAN) under different carbonization conditions. Carbonization of oxi-PAN fiber was performed under four different temperature (1300, 1400, 1500, $1600^{\circ}C$) with four different fiber tensions (14, 25, 35, 45 MPa). Effect of carbonization process on the structural development and mechanical properties of carbon fiber were characterized by single filament fiber tensile test and Raman spectroscopy. A clear correlation exists between the Raman spectrum and the tensile modulus of carbon fiber and effect of carbonization temperature on the tensile modulus showed increased tendency only at higher fiber tension (${\geq}25MPa$) while tensile strength showed decreased or random tendency. Therefore, it may be concluded that the optimization of carbonization temperature of oxi-PAN fiber also requires optimization of fiber tension.

• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.5 no.1
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• pp.26-31
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• 1975

The author observed a rare case of fibrous dysplasia in 12years old female who came to the Infirmary of Dental College, Seoul National University, complaining of facial asymmetry at 3 years' duration in right maxilla-facial region. The serial radiograms has been taken and the nature of the ]esion established as a typical fibrous dysplasia according to the interpreted findings in their images. The author has obtaind the results as follows: 1. Fibrous dysplasia occured at 3 years of age in this case. 2. Familial tendency, traumatic history and endocrine. disturbances: were: not noted in this patient. 3. The serial radiograms revealed a typical fibrous dysplasia encroaching Tight zygomatic bone.

• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.9 no.1
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• pp.37-43
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• 1979

The authors observed 2 cases of fibrous dysplasia on the cranial and maxillofacial bones in 31, 28 aged sisters, who had come to the Infirmary of Dental College, Yonsei University. The serial roentgenograms and clinical findings had been taken and the results established as polyostotic fibrous dysplasia according to the findings in their images. The authors have obtained the results as follows: 1. Bony expansion of the mandible occured at 18 years of age and the facial assymetry appeared due to development of the lesions. 2. The traumatic history were not noted but weak tendency of familial history noted 3. Endocrine disturbances, hyperpigmentation on the skin and premature puberty in the infancy were not noted. 4. We have concluded these diseases as polyostotic fibrous dysplasia on the cranial and maxillofacial bones with weak familial tendency according to the findings

• Proceedings of the KOR-BRONCHOESO Conference
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• 1991.06a
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• pp.24-24
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• 1991

기관협착증은 이비인후과 영역에 있어서 치료가 어려운 질환중의 하나로 이의 재건에는 여러가지 자가조직이 각각의 장점에 따라 사용되어 왔지만 완전하고 만족할만한 결과를 얻지 못하는 실정이다. 저자들은 가토의 자가 늑연골 (1군) 및 늑연골막 (2군)을 이용한 기관 재건술을 시행하여 다음과 같은 결과를 얻었다. 1) 이식편은 술후 10주 (1군) 및 12주 (2군)에 흡수나 섬유조직으로의 대치는 없었으며, 기관강의 크기는 직상 하부의 정상기관과 큰 차이가 없었다. 2) 늑연골을 이식한 부위는 연골막의 내세포층에서 연골세포가 분화, 이동되어 절단된 연골사이로 이동하여 새로운 연골을 형성하였다. 3) 늑연골막을 이식한 부위는 연골막에서 형성된 연골세포 및 연골기질이 절단된 연골사이로 이동하여 새로운 연골을 형성하였다. 4)) 이식한 부위의 점막층은 점막재생이 이루어져 원주상피로 피복되었다. 5) 기관 전벽의 결손부위는 늑연골 및 늑연골막을 이용하여 성공적으로 재건되었다.

• Imaging Science in Dentistry
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• v.30 no.2
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• pp.117-122
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• 2000

Fibrous dysplasia is a benign disorder of bone consisting of intramedullary proliferation of fibrous tissue and irregularly distributed, poorly developed bone. The disease manifests itself in the monostotic form in which only one bone is involved and the polyostotic form in which multiple bones at different sites are affected. We reported a extensive case of polyostotic fibrous dysplasia with involvement of craniofacial bones, mandible, ribs and extremities. A 18-year-old man showed remarkable right facial swelling who had been treated on right femur 3 years ago with a bone graft for pathologic fracture and he recognized facial swelling 5 years ago. Extraoral radiograms and computed tomogram showed diffuse sclerosis with a ground glass appearance of the most cranial bones, facial bones. The right mandibular lesion showed very expansile lesion with mottled appearance. Bone scans showed mutifocal increased uptakes in craniofacial bones, right mandible, bilaterally in ribs, humerus, femur, tibia and characteristic varus deformity of right femur (shepherd's crook defomity). This case showed exceptionally bilateral, extensive nature of bone lesion and didn't show any features of skin pigmentation and endocrine disturbances.

• Journal of Life Science
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• v.26 no.10
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• pp.1202-1206
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• 2016

Unicellular cyanobacterial strains of Subsections I and II and filamentous cyanobacterial strains of Subsection III have been shown to be polyphyletic, heterocystous strains of Subsections IV and V, both of which were previously reported to be monophyletic. In this study, the small subunit ribosomal RNA (16S rRNA) sequences of 13 strains of cyanobacteria - one strain, Oscillatoria nigro-viridis PCC7112, of the Subsection III, 6 strains including genus Anabaena, Nostoc, Tolypothrix, Calothrix and Scytonema of the Subsection IV, and 6 strains including genus Hapalosiphon, Fischerella and Chlorogloeopsis of the Subsection V - were determined. The phylogenetic analysis of cyanobacteria was carried out using the 16S rRNA sequences. The results of the phylogenetic analyses of 16S rRNA sequences, based on Neighbour-joining, maximum-parsimony, and maximum-likelihood methods, indicated that the members of Subsection IV were not monophyletic but polyphyletic. In addition, the phylogenetic results strongly indicated that the genus Scytonema in Subsection IV could be a common ancestor of heterocystous cyanobacteria in Subsection IV and V. Furthermore, the phylogenetic analyses revealed that the genus Anabaena could be phylogenetically diverse and that cyanobacterial strains in Subsection IV might be polyphyletic, whereas those in Subsection V could be monophyletic, as reported before. The results for the genus Anabaena indicate that it should be reclassified.