• Title/Summary/Keyword: Spindle head

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A case of a Spindle cell/pleomorphic lipoma in the lateral neck (측경부에 발생한 방추세포 / 다형성 지방종1예)

  • Kim, Young Yoon;Yoon, Sung Ho;Park, Jong Min;Lee, Dong Hoon
    • Korean Journal of Head & Neck Oncology
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    • v.34 no.1
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    • pp.41-43
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    • 2018
  • The Spindle cell lipoma is a slow-growing benign tumor seen generally in the shoulders, upper back, and back of the neck of male. The Pleomorphic (giant-cell) lipoma is a benign tumor of adipose tissue with atypical histological features. It is mainly seen in the same lesion as the Spindle cell lipoma. The Pleomorphic lipoma is cytogenetically similar to spindle cell lipoma with a consistent loss of chromosome 16q material. For this reason, these two entities are regarded as a similar spectrum in the adipose tumors. Herein, we present a 53-year old man with Spindle cell/pleomorphic lipoma in the lateral neck. Physical and radiologic examinations of the Spindle cell/pleomorphic lipoma in the lateral neck are not specific and preoperative diagnosis is usually difficult. Therefore, clinicians should consider the possibility that Spindle cell/pleomorphic lipoma may occur in the lateral neck mimicking the other more frequently observed lesions.

Unknown Primary Origin Metastatic Spindle Cell Carcinoma : A Case Report (원인불명의 경부전이성 방추형 세포암 1례)

  • Koh Joong-Wha;Kim Byung-Chul;Kim Seung-Kyun
    • Korean Journal of Head & Neck Oncology
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    • v.15 no.2
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    • pp.239-242
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    • 1999
  • Spindle cell carcinomas of the head and neck are unusual neoplasms that are histologically biphasic, having both squamous cell carcinoma and apparently malignant spindle cell or sarcomatous element. Controversy about the histogenesis of these tumors has resulted in various terminology ; sarcomatoid carcinoma, pseudosarcoma, carcinosarcoma, and spindle cell carcinoma. The clinical course and natural history of these tumors are also variable. We report a case of 64-year-old male who complained of a neck mass. The patient was treated with extended radical neck dissection and postoperative radiotherapy, but the primary site of spindle cell carcinoma could not be found. We reviewed the clinical course, treatment, prognosis, and histogenesis of spindle cell carcinoma of the head and neck.

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Spindle Cell (Sarcomatoid) Carcinoma of the Larynx : A Case Report (후두에 발생한 방추세포암종 1예)

  • Hong, Ki-Min;Jung, Gi-Hwa;Lim, Jae-Yol;Choi, Jeong-Seok
    • Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
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    • v.25 no.1
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    • pp.39-41
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    • 2014
  • Spindle cell carcinoma is an uncommon type of squamous cell carcinoma characterized by a mixture of malignant epithelial and mesenchymal cells. Most spindle cell tumors are polypoid and pedunculated. It is usually detected at an early stage, removed by laryngoscope guided polypectomy at the time of diagnosis, and seems to have good prognosis. The tools for diagnosing spindle cell carcinoma are histopathological analysis and immunohistochemical analysis. With reviews of literature, we report a 72-year-old patient complaining of hoarseness and dysphagia who was later diagnosed as spindle cell carcinoma.

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A Study on the Miniaturization of Angle Head Spindle Case for Cutting in Narrow Spaces (협소 공간 절삭가공용 앵글 헤드 스핀들 케이스 소형화에 대한 연구)

  • Sung, Chul Hoon;Han, Sung Gil;Kim, Sung Hoon;Song, Chul Ki
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.18 no.6
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    • pp.98-105
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    • 2019
  • In order to improve the fuel economy and dynamic behavior of automobiles, the weight reduction tendency of automobile parts is obvious. Also, in order to maximize assembly and maintenance convenience, various parts are integrated and modularized. Multi-piece methods require many manufacturing processes and become a factor of lowering the strength of parts. It is advantageous to overcome the disadvantages by integrally manufacturing to reduce the processing steps and ensure the strength of the parts. However, when it is necessary to process in a narrow space inside the part, it is impossible to process with the existing spindle. The angle head spindle is only a component of a machine tool, but it is a core part that requires high technology and is highly utilizable in products requiring high precision machining. Therefore, various and continuous studies needs for angle head spindles in areas such as vibration absorption, operational safety, excellent dimensional stability, and strength. In this paper, we propose an optimal design for angle head spindle by performing structural analysis and shape optimization for angle head spindle gear and case.

Design of Special-purpose Machine Tool Based on a Multi-spindle Head (다축 스핀들 헤드 기반의 전용 공작기계 설계)

  • Maeng, Heeyoung;Park, Juwook;Park, Hongkeun
    • Journal of the Korean Society of Manufacturing Technology Engineers
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    • v.24 no.6
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    • pp.675-681
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    • 2015
  • When many holes on a plane are machined simultaneously, the positional precision and machining efficiency are very important. Multi-spindle heads are typical order making products of which the number of shafts and hole positions vary depending on the size or form of the product. For the automatic design of multi-spindle heads, the design modules for power transmission systems for drive, idle, and spindle shafts were developed, and a design technique the determining the optimum position and number of idle shafts according to gear positions was developed. In addition, for the precise determination of the multi-spindle head, the design methods for the guide planes of columns, and feed mechanisms were devised. In addition, the design modules for accurate clamping and automatic transportation mechanisms were developed. Finally, in order to simplify and standardize the design process, the design analysis and simulation verification modules are integrated.

Experimental Study on the Electrostatic Discharge in the HDD Spindle System Using Fluid Dynamic Bearings (유체동압베어링을 사용하는 하드디스크 드라이브 스핀들 시스템에서 발생하는 정전기 방전에 관한 실험적 연구)

  • Kang, Min-Gu;Jang, Gun-Hee
    • Transactions of the Korean Society for Noise and Vibration Engineering
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    • v.16 no.1 s.106
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    • pp.75-80
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    • 2006
  • This paper introduces the mechanism of the ESD(electrostatic discharge) in the HDD spindle system using FDBs(fluid dynamic bearings). When a HDD(hard disk drive) spindle system is rotating, triboelectric charging occurs in the FDBs through the friction between the lubricant and the rotating shaft or between the lubricant and stationary sleeve. And this electrostatic charge is accumulated in the rotating parts of the HDD spindle system because they are insulated from the ground by the lubricant. This research shows experimentally that the behavior of electric charge and discharge in the FDB spindle system is the same as that of a capacitor. It also measures the electrostatic voltage difference between the rotating and stationary parts in the FDB spindle system due to the change of humidity, supporting load and motor speed. This research shows that the control of ESD is required in the HDD spindle system using FDBs, because the electrostatic charge accumulated in the FDB spindle system may cause the breakdown damage of the GMR head and data loss consequently.

Experiental Study on the Electrostatic Discharge in the HDD Spindle System Using Fluid Dynamic Bearings (유체동압베어링을 사용하는 하드 디스크 드라이브 스핀들 시스템에서 발생하는 정전기 방전에 관한 실험적 연구)

  • Kang, Min-Gu;Jang, Gun-Hee
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2005.11a
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    • pp.318-323
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    • 2005
  • This paper introduces the mechanism of the ESD (Electrostatic discharge) in the HDD spindle system using FDBs (Fluid Dynamic Bearings). When a HDD (Hard Disk Drive) spindle system is rotating, triboelectric charging occurs in the FDBs through the friction of the lubricant between the rotating shaft and stationary sleeve. And this electrostatic charge is accumulated in the rotating part of the HDD spindle system because it is insulated from the ground by the lubricant. This research shows experimentally that the behavior of electric charge and discharge in the FDB spindle system is the same as that of a capacitor. It also measures the electrostatic charge and discharge of the FDB spindle system due to the chanse of humidity, supporting load and motor speed. This research shows that the control of ESD is required in the HDD spindle system using FDBs, because the electrostatic charge accumulated in the FDB spindle system may cause the breakdown damage of the GMR head and data loss consequently.

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A Case of Recurrent Spindle Cell Epithelial Tumor of Thymus-Like Differentiation (SETTLE) in the Glottis (성문에서 발생한 재발성 흉선상 방추상 상피세포 종양(Spindle Epithelial Tumor with Thymus-Like Differentiation, SETTLE) 1예)

  • Park, Woori;Choi, Nayeon;Chung, Man Ki
    • Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
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    • v.26 no.2
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    • pp.133-136
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    • 2015
  • Spindle epithelial tumor with thymus-like differentiation (SETTLE) is an extremely rare type of thyroid tumor, with spares reports on its clinical course. SETTLE is derived from branchial pouch or thymic remnants, and classified as a low grade, malignant neoplasm due to its indolent growth and tendency to develop delayed metastasis. Therefore, stringent initial workups and long-term follow-up are required to prevent misdiagnosis. We present a case of recurrent spindle epithelial tumor with thymus-like differentiation (SETTLE) in the glottis of 57 year-old male patient, who had a history of surgical excision for the SETTLE from the thyroid gland 5 years ago. Transoral CO2 laser surgery was performed to remove the glottic tumor and there was no evidence of local recurrence at 11 months postoperatively.

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A Forging Analysis and Mechanical Properties Evaluation of Superalloy Exhaust Valve Spindle (초내열 합금 배기 밸브 스핀들 단조 해석 및 기계적 특성 평가)

  • Choi, S.G.;Oh, J.S.;Jeong, H.S.;Cho, J.R.
    • Proceedings of the Korean Society for Technology of Plasticity Conference
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    • 2009.10a
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    • pp.84-88
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    • 2009
  • The nickel-based alloy Nimonic 80A possesses strength, and corrosion, creep and oxidation resistance at high temperature. The exhaust valves of low speed diesel engines are usually operated at temperature levels of 400-$600^{\circ}C$ and high pressure to enhance thermal efficiency and exposed to the corrosion atmosphere by the exhaust gas. Also, the exhaust valve is subjected to repeated thermal and mechanical loads. So, the nickel-based alloy Nimonic 80A was used for the large exhaust valve spindle. It is composed a 540mm diameter head and a 125mm diameter stem. It is developed large products by hot closed-die forging. Manufacturing process analysis of the large exhaust valve spindle was simulated by closed die forging with hydraulic press and cooled in air after forging. The preform was heated to $1080^{\circ}C$ 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. Mechanical properties of the large exhaust valve spindle were evaluated by the variety of tests, including microstructure observation, tensile, as well as hardness and fatigue tests, were conducted to evaluate the mechanical properties for head part of exhaust valve spindle.

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A Case Study on the Failure of Intake and Exhaust Valves for Marine Diesel Engines

  • Kim Jong-Ho
    • Journal of Advanced Marine Engineering and Technology
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    • v.29 no.7
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    • pp.801-807
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    • 2005
  • Any failure of intake and exhaust valves of marine diesel engine must be regarded as serious, and any steps which can be taken to prevent such failure are desirable. The purposes of this study is to investigate and to analyse the failure causes of intake and exhaust valves for marine diesel engine during sea trial after completion of overhauling. In this study, to analyse the failure causes, we have carried out on board inspection, fractography test and discussion based on the specimen and repairing report provided by the ship owner. From the results of above inspection, test and discussion, it has been considered reasonable to conclude that the causes of damaged valves of the ship are as follow ; 1) During operation, the stick or seizure of valve spindle occurred and hence the movement of exhaust valve spindle was to be resisted and subsequently the engine was to be operated under an unappropriated valve timing and the exhaust valve sustained the repeated loads exceeding the fatigue strength of valve material. 2) By the loads above described, the fatigue fracture was initiated at the structural noncontinuous part of exhaust valve spindle, and then the valve head was finally fractured and dropped in the cylinder. 3) The fractured exhaust valve head impacted the intake valve at various direction to be bent or damaged.