• Korean Journal of Head & Neck Oncology
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• v.17 no.2
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• pp.226-229
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• 2001

Synovial sarcoma is commonly found in the extremities of mesenchymal origin, but rare in the head and neck area. Histopathology is diagnostic and it shows a biphasic pattern with two neoplastic elements; spindle cell, sarcoma like stroma and gland like clefts lined by epitheloid cells. Synovial sarcoma is high-grade neoplasm that expresses epithelial as well as supporting features. This paper presents a case of synovial sarcoma of hypopharynx on 25 years old male. He was treated by surgical excision and postoperative chemoradiotherapy. There were no evidences of local recurrence & distant metastasis for 19 months postoperatively.

• Korean Journal of Head & Neck Oncology
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• v.9 no.2
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• pp.221-226
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• 1993

Hamangiopericytoma, first described by Stout & Murray in 1942, is a rare vascular tumor composed of spindle-shaped or rounded cells proliferating around endothelial lined capillaries. These proliferating cells were belived to arise from the pericytes of Zimmerman. Histologically, this tumor demonstrates great variability and clinical course cannot be predicted from the histological appearance. Head and Neck hemangiopericytoma appears to have a lower grade malignancy with frequent local recurrency and metastasis, therefore, aggressive surgical therapy should be the treatment of choice. We experienced a case of hemangiopericytoma occurred in the right skull base at submastoideal and suboccipital area presenting as neck mass in upper occipital triangle in a 42 years old female patient and we report it with a review of literatures.

• Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
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• v.28 no.2
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• pp.128-130
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• 2017

Sarcomatoid carcinomas are biphasic tumors which have surface epithelial changes and an underlying spindle-shaped neoplastic proliferation. A 62-year-old male with hoarseness came to our hospital for evaluation. A single smooth polypoid lesion was detected on his right true vocal fold by larnygoscope. The patient was diagnosed with vocal polyp and treated with surgical excision. Pathology report of the excised specimen was compatible with sarcomatoid carcinoma. Therefore, further surgical resection was performed to secure safety margins. We report a case of a sarcomatoid carcinoma patient who was clinically diagnosed as vocal polyp.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.49 no.2
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• pp.61-67
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• 2023

This systematic review aimed to analyze the clinicopathological profile and relevant prognostic factors of head and neck rhabdomyosarcoma in pediatric patients. The search was carried out in the electronic search portals PubMed, Lilacs, Embase, Scopus, and Web of Science. The search yielded studies that were then analyzed regarding study topic, data extraction, and risk of bias using the STROBE (Strengthening the Reporting of Observational Studies) guidelines. Finally, three studies were included for qualitative analysis. Most of the cases involved embryonic and alveolar rhabdomyosarcoma. Expression of MYOD1 was highly correlated with diagnosis of spindle cell/sclerosing rhabdomyosarcoma, which appears to have a poor prognosis in children. Furthermore, tumor size <5 cm and absence of metastasis accompanied by complete resection and administration of adjuvant therapies such as chemotherapy and radiotherapy favored a better prognosis.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2001.04a
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• pp.309-314
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• 2001

The balance of high speed spindle system with high precision rotation like grinding machine is very important. Traditionally, we use trial and error method to balance the spindle. It takes much time. So we are developing the automatic balancing equipment being used in the grinding machine. The balancing head we develop is wireless. It will be used high-speed grinding machine. We use influence coefficient method to control the automatic balancer. Experiments are based on automatic and manual balancing. We perform test of the vibration filter. It helps to remove noise. The filter and experiments with automatic balancing controller show that automatic balancing control can be successfully achieved with the quick response and good stability characteristics.

• Proceedings of the Korean Society of Marine Engineers Conference
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• 2006.06a
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• pp.29-30
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• 2006

나이모닉 일체형으로 사용되고 있는 선박용 2 행정 저속엔진의 배기밸브 스핀들을 고온, 고압, 배기가스 및 반복 충격 하중에 노출된 스핀들의 Head부분은 기존의 나이모닉 소재를 적용, 기존 재질의 우수한 성질을 유지하고 설계적으로 나이모닉 소재의 적용이 불필요한 Stem부는 오스텐나이트 계열의 SNCrW 소재를 사용하여 관성마찰 용접 방식으로 접합하여 제품을 제작하고, 접합부의 미세조직 관찰, 성분분석, 인장, 경도, 피로시험 등의 기계적, 금속적 특성평가를 통해 마찰용접제품에 대한 신뢰성을 확인하고 양산 생산을 위한 기술적 토대를 마련하였다.

• Korean Journal of Head & Neck Oncology
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• v.39 no.2
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• pp.41-44
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• 2023

Follicular dendritic cell sarcoma (FDCS) is rare lymphoid sarcoma occurs anywhere in body, mostly in lymph nodes. Sixty-two-year-old man presented left submandibular gland region mass for 5 months. Mass excision with submandibular gland resection was performed. Histopathology showed proliferation of spindle and ovoid cells with storiform arrangement which were positive for CD21, CD23, Vimentin, Ki-67, suggested FDCS in submandibular gland region lymph node. Tumor size was 3cm with no involvement of resection margin, nor cellular atypia and necrosis, so regular follow up was performed. After 4 years, new enhancing mass in left submandibular area was found. Wide excision of mass with neck dissection on left level I-III was performed. Histopathology confirmed recurrence of FDCS. The patient underwent radiation therapy from left mandible to hyoid area. After 2 years, new nodule was found in left lung upper lobe, and wedge resection confirmed metastasis of FDCS. The patient is on adjuvant chemotherapy.

• Journal of Advanced Marine Engineering and Technology
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• v.29 no.8
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• pp.938-945
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• 2005

The microstructure evolution in hot forging process is composed of dynamic recrystallization during deformation as well as grain growth during dwell time. Therefore, the control of forging parameters such as strain, strain rate. temperature and holding time is important because the microstructure change in hot working affects the mechanical properties. Modeling equations are developed to represent the flow curve. grain size. recrystallized volume fraction and grain growth phenomena by various tests. The developed modeling equations were combined with thermo-viscoplastic finite element modeling to predict the microstructure change evolution during hot forging process. The large exhaust valve spindle (head diameter of 512mm) was simulated by closed die forging with hydraulic press and cooled in air after forging. The preform was heated to each 1080 and 1150$^{\circ}C$. Numerical calculation was performed by DEFORM-2D. a commercial finite element code. Heat transfer can be coupled with the deformation analysis in a non-isothermal deformation analysis. In order to obtain the fine and homogeneous microstructure and good mechanical properties in forging. the FEM would become a useful tool in the simulation of the microstructure development. In forging, appropriate temperature, strain and strain rate and rapid cooling are required to obtain the fine grain microstructure The optimal forging temperature and effective strain range of Nimonic 80A for large exhaust valve spindle are about 1080$\∼$l120$^{\circ}C$ and 150$\∼$200$\%$.

• Journal of Advanced Marine Engineering and Technology
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• v.29 no.8
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• pp.891-898
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• 2005

Inertia welding is a solid-state welding process in which butt welds in materials are made in bar and in ring form at the joint race, and energy required lot welding is obtained from a rotating flywheel. The stored energy is converted to frictional heat at the interface under axial load. The quality of the welded joint depends on many parameters, including axial force, initial revolution speed and energy amount of upset. working time, and residual stresses in the joint. Inertia welding was conducted to make the large exhaust valve spindle for low speed marine diesel engine. superalloy Nimonic 80A for valve head of 540mm and high alloy SNCrW for valve stem of 115mm. Due to different material characteristics such as, thermal conductivity and flow stress. on the two sides of the weld interface, modeling is crucial in determining the optimal weld geometry and Parameters. FE simulation was performed by the commercial code DEFORM-2D. A good agreement between the Predicted and actual welded shape is observed. It is expected that modeling will significantly reduce the number of experimental trials needed to determine the weld parameters. especially for welds for which are very expensive materials or large shaft. Many kinds of tests, including macro and microstructure observation, chemical composition tensile , hardness and fatigue test , are conducted to evaluate the qualify of welded joints. Based on the results of the tests it can be concluded that the inertia welding joints of the superalloy exhaust valve spindle are better properties than the material specification of SNCrW.

• Korean Journal of Head & Neck Oncology
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• v.26 no.1
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• pp.37-40
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• 2010

Ectopic hamartomatous thymoma is a rare benign tumor of the lower neck occurring in the male adult predominantly. The origin of this tumor has been debated, but it is now believed to arise from remnants of the cervical sinus of His from early development. They are composed of epithelial, adipocytic, and spindle cells in variable amounts. Recognition of ectopic harmatomatous thymoma is important and needs to be differentiated from high-grade sarcomas such as synovial sarcoma or glandular malignant peripheral nerve sheath tumor. We here report on a case of ectopic hamartomatous thymoma arising in the left lateral neck of 33-year-old male patient.