• 한국결정성장학회지
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• 제25권4호
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• pp.140-144
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• 2015

Tonpilz 트랜스듀서에서 head mass에 영향을 미치는 요소로써 그 형상과 무게 및 소재의 영향을 연구하였다. 형상 요소로는 head mass의 옆면이 대칭 축과 이루는 각도를 그 인자로 하여 0도, 35.5도, 60도로 변화시키면서 대역폭과 출력의 변화를 모사하였다. 그 결과 Al의 경우에는 35.5도에서 대역폭이 최대 값이 되었으며 그 때의 대역폭은 86.4 %로 계산되었다. Head mass의 중량은 대역폭에는 큰 영향이 없이 출력에만 영향을 미치는데 중량이 25 % 감소하였을 때 20 % 정도 출력이 증가하였다. 끝으로 head mass의 소재를 Ti로 변경하였을 때에는 밀도의 차이에 의한 무게의 증가에도 불구하고 출력이 100 % 향상되었는데 이는 Ti의 탄성률 같은 기계적 특성의 영향으로 판단되며 최대의 대역폭을 얻기 위한 형상은 45도에서 얻어졌고 대역폭은 88.1 %이었다.

• 제어로봇시스템학회논문지
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• 제15권3호
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• pp.330-336
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• 2009

This paper studies on the new control algorithm for the mass-flow stabilization in strip head part of a hot strip mill. A new strip tension model in the strip head part is derived using the current deviation of two neighboring stands. The current deviation means a difference between a measured current and a lock-on current, where the lock-on current is set up when a strip tension or a looper angle reaches each target value or time is about 0.4sec, respectively. On the basis of the tension calculation model, a mill velocity of a backward stand is controlled to stabilize a strip mass-flow by PI control algorithm. Therefore, the mass-flow control for strip head part is executed from a metal-in time into a foreward stand till the looper works normally. It is known by the results of a computer simulation and an experiment that the proposed control algorithm is very effective in stabilizing the mass flow of the strip head part.

• 한국음향학회지
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• 제29권7호
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• pp.422-430
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• 2010

Tonpilz 트랜스듀서의 방사 패턴은 구조 변수들에 의해 많은 영향을 받는다. 본 연구에서는 단일 모드 Tonpilz 트랜스듀서에 대해서 동일한 유효 면적을 가지는 다양한 전면추 형상에 따른 방사 패턴을 계산하였다. 트랜스듀서의 전면추 형상은 가장 많이 사용되는 원형과 정삼각형, 정사각형, 정육각형 및 정팔각형에 대해 분석하였으며, 각 형상에 대해 방사 패턴 수식을 유도하였다. 유도한 수식을 바탕으로 전면추 형상과 크기에 따른 방사 패턴의 변화를 해석하고, 서로의 특성을 비교하였다. 계산 결과의 타당성은 유한 요소 해석을 이용하여 확인하였다.

• 임상이비인후과
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• 제29권2호
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• pp.301-306
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• 2018

Immunoglobulin G4-related disease (IgG4RD) is a chronic inflammatory condition characterized by tissue infiltration with lymphocytes and IgG4-secreting plasma cells, as well as varying degrees of fibrosis. We report a case of a 70-year-old man with a rapid-growing cervical mass for several months. Computed tomography and positron emission tomography showed a huge, ill-defined mass involving left thyroid lobe and encasing the common carotid artery, which was clinically and radiologically suspicious for anaplastic thyroid carcinoma. Ultrasonography-guided core needle biopsy was performed and histopathology examination revealed to be consistent with IgG4RD, and the IgG4/IgG ratio was 0.6. After oral corticosteroid was administered, the mass was dramatically resolved. Because IgG4RD often presents as a single localized and infiltrated mass lesion, it can be confused and misdiagnosed as a malignancy. Thus, clinicians should consider IgG4RD as a differential diagnosis in a rapid-growing neck mass to prevent unnecessary and excessive treatments.

• 대한두경부종양학회지
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• 제10권2호
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• pp.157-162
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• 1994

It is the purpose of this paper to determine the relative frequency of the neoplastic vs. non-neoplastic disease in a series of surgically removed parotid and submandibular masses. The study was conducted a retrospective review of 249 consecutive, operated patients' records seen over a 9-year period from 1985 through 1993 at Department of Otolaryngology-Head and Neck Surgery, Korea Cancer Center Hospital. One hundred and fifteen patients had parotid mass and 134 patients had submandibular mass. All the specimen surgically removed were studied histopathologically. The numbers and percentages of patients are reported along with a pathological classification of the lesions encountered: neoplastic(benign, malignant) and non-neoplastic (inflammatory, non-inflammatory). There were 59 benign, 46 malignant, 6 inflammatory, 4 non-inflammatory in 115 parotid mass, and 33 benign, 48 malgnant, 47 inflammatory, 6 non-inflammatory in 134 submandibular mass. One-hundred-eighty-six of entire 249 patients had tumor involvement, for a 74.7% incidence of neoplasia. There was a neoplastic predominance in parotid mass(91.3%) and a relative inflammatory predominance in submandibular mass(35.1%).

• 대한두경부종양학회지
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• 제29권2호
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• pp.71-74
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• 2013

Neck mass is a common manifestation from head and neck malignancy, most of which come from mucosal squamous cell carcinomas in the upper aero-digestive tract. However, once aspiration cytology suggests atypical malignant cells in the neck mass rather than metastatic squamous cell carcinomas, it is confusing to decide the adequate diagnostic work-ups and treatment planning. Here, we report a 29-year-old woman presenting with a growing neck mass mimicking malignancy of unknown origin, which was finally diagnosed as primary lymphoepithelial carcinoma in the parotid gland with multiple metastases to the lymph nodes. The patient underwent comprehensive neck dissection and total parotidectomy and the adjuvant radiation treatment was given. Our report highlight that the primary salivary gland cancer should be considered as the potential tumor origin in case of malignancy of unknown origin in the head and neck region and neck mass suggestive of atypical carcinomas.

• 대한두경부종양학회지
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• 제26권2호
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• pp.250-252
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• 2010

Vascular leiomyomas are benign tumors of smooth muscle origin arising from the muscularis layer of blood vessel walls. They can occur anywhere in the body where smooth muscle is found and usually occur in the lower extremity as a slow-growing, firm, occasionally painful mass. However they are rare in the head and neck and very rare in hard palate. Here we report a case of a vascular leiomyoma presenting as a soft mass of the hard palate and review the literatures.

• 대한두경부종양학회지
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• 제26권2호
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• pp.221-224
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• 2010

Papillary thyroid carcinoma frequently invades the lymph node, trachea, esophagus and perithyroid tissue. However, direct extension to posterior pharyngeal area is known to be rare. A 64-year-old male was referred to our clinic presenting as posterior pharyngeal mass during gastrofiberscopy. The neck CT scan showed soft tissue mass in retropharynx and lymph node in right level III with calcifications. We performed the total thyroidectomy with selective(level II, III, IV) and anterior compartment neck dissection. In operative findings, the right thyroid mass were connected to the retropharynx through the posterior portion of inferior constrictor muscle. Histopathologic findings revealed the papillary thyroid carcinoma extended to retropharynx. We report a unique case with a literature review.

• 대한기관식도과학회지
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• 제13권2호
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• pp.72-77
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• 2007

The case report of migrating ingested fish bone presenting as an unresolving inflamed neck mass is rare. The diagnosis must be suspected in a patient with an unresolving inflamed cutaneous lesion, especially one with a punctum, the tenderness of the lesion elicited on swallowing and the presence of a palpable subcutaneous neck mass. In such a patient, a history of recent foreign body ingestion must be actively sought. An accurate early diagnosis of this easily treatable condition is desirable because it could avert unnecessary delays, inconveniences, anxiety, costs, and surgery. The authors experienced a case of lateral neck mass resulting from the migration of a fish bone which was successfully removed by surgical exploration and made a report with a review of literature.

• 대한두경부종양학회지
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• 제23권2호
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• pp.178-180
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• 2007

Tortuosity of the internal carotid artery is not a rare condition. A 68-year-old woman presented with a 3 years' history of a pulsatile tinnitus and throat abnormal sensation. On physical examination, a soft pulsatile mass on the left posterior oropharyngeal wall was noted. By neck CT and neck MRI the tortuous internal carotd artery was visualized. Otolaryngologists should recognize this anomaly and the patient should be made aware of their condition, because it may cause a fatal or near-fatal hemorrhage during surgical procedures in the pharynx, especially tonsillectomy and adenoidectomy and drainage of peritonsillar abscess. We report a case of a left internal carotid artery tortuosity as an oropharyngeal mass.