• Journal of Astronomy and Space Sciences
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• 제23권3호
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• pp.209-216
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• 2006

Ion acoustic solitary wave in a plasma consisting of electrons and ions with an external magnetic field is reinvestigated using the Sagdeev's potential method. Although the Sagdeev potential has a singularity for n < 1, where n is the ion number density, we obtain new solitary wave solutions by expanding the Sagdeev potential up to ${\delta}n^4$ near n = 1. They are compressiv (rarefactive) waves and shock type solitary waves. These waves can exist all together as a superposed wave which may be used to explain what would be observed in the solar wind plasma. We compared our theoretical results with the data of the Freja satellite in the study of Wu et al. (1996). Also it is shown that these solitary waves propagate with a subsonic speed.

• Journal of Korean Dental Science
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• 제12권2호
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• pp.66-72
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• 2019

Osteochondroma is a bone tumor with cartilaginous growth potential that generally appears near the growth plate of long bones in areas such as hip, knee, and shoulder joints, related to the nature of endochondral ossification and it is known a common benign bone tumor. However, it has been very rare in craniofacial region possibly because craniofacial bone is largely formed by intramembranous ossification. Moreover, reports on the solitary type of osteochondroma in mandibular condyle has been extremely rare. Osteochondroma in mandibular condylar may show various symptoms similar to general temporomandibular joint disorders (TMDs), such as pain in the condylar area during mouth opening, internal derangement, facial asymmetry or posterior open bite. Therefore, it can be disregarded for a long time period without any adequate treatment. Surgical excision has been the treatment option for the solitary osteochondroma with very low recurrence rate reportedly. In this case report, a rare case of solitary osteochondroma developed in unilateral mandibular condyle is presented with emphasis on differential diagnosis with general TMDs.

• 한국안전학회지
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• 제32권6호
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• pp.61-67
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• 2017

Suspended sediment transport plays principal roles in morphological process of natural coastals. It is needed to understand the reason why interaction characteristics of solitary wave and suspended sediment. The present study shows that suspended sediment pickup derived on solitary wave celerity. The 2D prismatic open channel length is 12 m, width is 0.8 m, height is 0.75 m and slope is 1/6. Generation of solitary wave is used by rapidly opening the sluice gate. Bottom surface sediments are laid movable slope section by 0.03 m thickness and experimental sediments are used anathracite and jumoonjin sand. Techniques of suspended sediment pickup rate are designed equipment ASC(Absorptive Suspended sediment Collector). It could directly absorb 5 points suspended sediment by channel water depth. Solitary wave celerity is measued by ADV(Acoustic Doppler Velocimeter). Mounted two video cameras(Model No. : Sony, HDR-XR550) are used to image processing of suspended sediment concentration and turbidity. Suspended sediment pikcup rate(Einstein, 1950) is analyzed to nondimensionalization based on solitary wave celerity. The suspended sediment pickup rate is suggested that more effective plunging breaking type than spilling. The results indicates fundamental suspended sediment transport mechanism between solitary wave celerity and suspended sediment pickup based on laboratory experiments. Finally, the present study suggests that suspended sediment pickup rate by solitary wave is used only characteristics of sediment and solitary wave celerity.

• 대한치과보철학회지
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• 제54권4호
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• pp.401-406
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• 2016

임플란트 피개의치는 전통적인 총의치에 비해 높은 유지력 및 저작능력, 환자의 만족도를 보인다. 특히 골흡수가 심한 하악 무치악 환자의 치료에서는 우선되는 치료방법으로 고려된다. 임플란트 피개의치를 위한 attachment에는 임플란트간 연결된 bar type과 연결되어있지 않은 solitary type으로 구분할 수 있다. 최근 임상에서 많이 사용하는 solitary type의 경우 임플란트간의 평행관계가 중요하며, 임플란트간의 평행관계가 불량한 경우 attachment의 마모 및 유지력 감소로 유지관리를 내원횟수가 증가할 수 있다. 본 증례는 평행하지 못한 두 개의 하악 임플란트 식립 환자에서 milled bar를 이용하여 제작한 임플란트 피개의치로 만족할 만한 결과를 얻었기에 이를 보고하고자 한다.

• 한국시뮬레이션학회논문지
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• 제12권2호
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• pp.75-89
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• 2003

This paper describe numerical experiments with solitary beams in a self focusing Kerr medium with fast response. Through formal analogies, it compare this results on the phase sensitivity of beam collision with known predictions about one dimensional soliton interaction. For incoherent oblique beam interaction, there occurs a non-periodic coupled-mode type transfer of energy, resulting in complete transmission each beam through the other one.

• 대한세포병리학회지
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• 제2권2호
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• pp.134-141
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• 1991

Localized or solitary fibrous tumor (SFT) of the pleura has been classified as a type of mesothelioma, arising from the submesothelial connective tissue cells. The preoperative diagnosis of the tumor at the cytologic or histologic level is very important for the proper handling of the lesion. This preoperative diagnosis is now possible by means of the advance in the transthoracic fine needle aspiration biopsy (FNA) techniques and in the very experience of the cytopathologists. We describe FNA cytologic feature of two cases of SFT arising from the pleura. Cytologic, histologic, immunohistochemical, and electron microscopic characteristics of pleural SFT are discussed. The tumor cells of SFT are spindle or oval in shape with a variable amount of cytoplasm. They are arranged in irregular trabeculae intimately associated with capillaries. A unique cytologic feature observed in this tumor is that thick, eosinophilic, amorphous collagen bundles are scattered between tumor cells.

• Archives of Reconstructive Microsurgery
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• 제22권2호
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• pp.78-81
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• 2013

Neurofibroma may present as a solitary lesion or as multiple lesions. Although there is no site of predilection for solitary lesions, occurrence on the hand is rare. Plexiform neurofibroma can develop in isolation or more commonly as a part of neurofibromatosis type 1. In those that apper in isolation, trauma has been suggested as a precipitating factor. A 68-year-old male farmer had experienced repetitive prior episodes of trauma in the involved finger. He presented with a painless mass on the dorsal aspect of the fifth finger. Physical examination showed a protruding mass measuring approximately $15{\times}20mm$ which was not tenderness to palpation and any skin changes or pigmentation. Ultrasonography showed a cystic mass on the dorsal aspect of the middle phalanx. Microsurgical dissection was applied in order to seperated the lesion from the ulnar side of the dorsal branch of the digital nerve. Pathologic examination of the specimens revealed neurofibroma. At three-month follow-up, motor and sensory function were intact, and range of motion was fully recovered. Traumatic solitary neurofibroma is a rare tumor of the hand, especially in the finger. Hand surgeons should be aware of the diagnostic possibilities of this tumor based on examination, history taking and imaging studies.

• Archives of Plastic Surgery
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• 제38권1호
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• pp.109-112
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• 2011

Purpose: Neurofibromas may present as multiple or solitary lesions. Although there is no predilection site for solitary lesions, they are rare on the hand. In addition, solitary intramuscular neurofibromas are a very rare pathological type. Here, we report a rare solitary intramuscular neurofibroma in the hand. This paper examines the clinical characteristics of intramuscular neurofibroma arising from the lumbricalis in order to enable a correct diagnosis and treatment. Methods: A 32-year-old male presented with a painless mass on the palm. The physical examination revealed a $3{\times}2$ cm protruding mass that was non-tender to palpation. The vascular and sensory examinations were unremarkable, while the motor examination showed mild difficulty with flexion and extension. Magnetic resonance imaging demonstrated an enhancing solid mass between the thenar eminence and second metacarpophalangeal joint. The diagnosis of an intramuscular neurofibroma was confirmed following surgical excision and histological evaluation. Results: The pathological examination was consistent with a neurofibroma, with delicate fascicles and loose fusiform cells in a fibrous stroma, with oval or spindle-shaped nuclei and scant cytoplasm. The background matrix was pale staining and had focal myxoid stroma. There was no significant nuclear pleomorphism and no mitoses. Immunohistochemistry with S-100 was slightly positive. At the 6-month follow-up, motor and sensory function were intact and the range of motion was full. Conclusion: A neurofibroma is a rare tumor of the hand, especially the intramuscular type. Hand surgeons should consider the diagnosis of this tumor based on the examination and imaging.

• Journal of Korean Neurosurgical Society
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• 제30권sup1호
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• pp.140-143
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• 2001

We report a case of huge trigeminal schwannoma in a 10-year-old boy with neurofibromatosis type II, extending into the three spaces of the left middle, posterior, and infratemporal fossa. Initially we thought the child had a solitary trigeminal schwannoma, and most of the mass was resected successfully through one-stage operation, cranio-orbito-zygomatic intradural approach. However during the follow-up of the patient we found radiographically other multiple intracranial tumors of bilateral acoustic schwannomas, right trigeminal schwannoma, and foramen magnum tumor. Eventually the patient was diagnosed as neurofibromatosis type II presenting multiple intracranial tumors. We think childhood trigeminal schwannoma, even though in the case of solitary tumor, should be considered as possible initial manifestation of neurofibromatosis type II and that careful follow-up for the possibility of occurrence of other brain tumors such as schwannomas or meningiomas is necessary.

• Journal of Korean Neurosurgical Society
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• 제52권6호
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• pp.564-566
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• 2012

Non-Hodgkin's lymphoma rarely originates from bone, and even more infrequently from a vertebral body. Lymphoblastic lymphoma is a rare type of non-Hodgkin's lymphoma, and results from an abnormality in adaptive immune cells. A 27-year-old man presented with a two-month history of night sweats, weight loss, and severe back pain. Radiological studies demonstrated an osteolytic lesion compressing the subarachnoid space at the T11 level. Posterolateral fusion with decompression was performed and a pathologic examination confirmed lymphoblastic lymphoma of the B-cell precursor type. To our knowledge, this is the first report of solitary lymphoblastic lymphoma from B-cell precursors in of the thoracic spine. Herein, we discuss the presenting symptoms and the management of this rare case of lymphoblastic lymphoma.