• 한국의학물리학회지:의학물리
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• 제19권4호
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• pp.219-226
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• 2008

이 연구에서는 저자들이 개발한 비정질 셀레늄층과 비정질 실리콘TFT배열을 사용하는 직접방식 디지털 X-선 영상 검출기에 대해 IEC (international electrotechnical commission)와 같은 국제표준으로 권고된 측정방법에 따라 특성을 평가하였다. 영상 성능 묘사에 사용되는 측정은 응답특성(response characteristic), 변조전달함수(MTF, modulation transfer function), 잡음전력스펙트럼(NPS, noise power spectrum), 양자검출효율(DQE, detective quantum efficiency), 양자제한 성능을 포함하고 있다. 영상특성평가 결과, 개발된 검출기의 DQE 값은 최저주파수와 최고주파수에서 각각 40%와 25%이었다. 해외 타사의 제품과 비교해서도 우월한 값을 나타내었다. 또한 MTF는 간접방식 DR, CR과 비교하면 매우 우월한 성능을 보이고 있다. 또한 양자 제한된 특성을 평가한 결과, 0.023 mR 이하에서만 제한된 특성을 보여 일반촬영용도로서 적합성을 확인할 수 있었다.

• Journal of Korean Neurosurgical Society
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• 제57권4호
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• pp.292-294
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• 2015

Vestibular schwannoma (VS) usually present the widening of internal auditory canal (IAC), and these bony changes are typically limited to IAC, not extend to temporal bone. Temporal bone invasion by VS is extremely rare. We report 51-year-old man who revealed temporal bone destruction beyond IAC by unilateral VS. The bony destruction extended anteriorly to the carotid canal and inferiorly to the jugular foramen. On histopathologic examination, the tumor showed typical benign schwannoma and did not show any unusual vascularity or malignant feature. Facial nerve was severely compressed and distorted by tumor, which unevenly eroded temporal bone in surgical field. Vestibular schwannoma with atypical invasion of temporal bone can be successfully treated with combined translabyrinthine and lateral suboccipiral approach without facial nerve dysfunction. Early detection and careful dissection of facial nerve with intraoperative monitoring should be considered during operation due to severe adhesion and distortion of facial nerve by tumor and eroded temporal bone.

• 한국유체기계학회 논문집
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• 제1권1호
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• pp.17-23
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• 1998

The blade failures are identified as the leading cause of unplanned outages for steam turbine. Most investigations of the failures are limited to material tests, chemical analysis of deposits, and possibly examination of material specimens. But to correct a blading problem requires more than positive identification of the mechanisms involved. An analytic procedure capable of predicting stress and dynamic characteristics of turbine blades is presented to increase steam turbine availability by decreasing blade failures. Finite element method is used to model and predict natural frequencies, steady and dynamic stresses of turbine blades. The procedure is illustrated by the case study. This procedure is used to guide, and support the plant manager's decision to avoid a costly, unplanned outage

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2003년도 생물공학의 동향(XII)
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• pp.95-97
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• 2003

본 연구에서는 손상된 심근의 재생을 위하여 골수단핵세포를 SD 래트에 이식하였고 5주 후에 심근의 재생, 신생혈관의 형성과 더불어 심장의 기능이 향상되었음을 확인할 수 있었다. 골수단핵세포를 손상된 심근경색 부위에 넣어주는 것은 추가 보완 실험을 통하여 심근경색의 치료법으로서 이용될 수 있을 것이다.

• 대한세포병리학회지
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• 제12권1호
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• pp.31-37
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• 2001

Whlie cytologic characteristics of squamous dysplasia, carcinoma in situ, and invasive squamous cell carcinoma of the uterine cervix are well documented, relatively few studios have dealt with the cellular features of microinvasive carcinoma. In order to describe the cellular characteristics of microinvasive squamous cell carcinoma, we retrospectively reviewed 45 cervovaginal smears(15 carcinoma in situ, 15 microinvasive cancer, 15 invasive cancer) which were confirmed by histologic examination of specimens obtained by hysterectomy at the Seoul National University Hospital during S years from 1995 to 1999. The cytologic features about tumor diathesis, inflammatory background, ceil arrangement, anisonucleosis, nuclear membrane irregularity, nuclear chromatin pattern, and nucleoli were observed. The cytologlc characteristics of microinvasive squamous cell carcinoma of the uterine cervix are syncytial pattern, mild tumor diathesis, the irregularity of nuclear membrane, irregularly distributed nuclear chromatin, and occurrence of micronucleoli. But, correlation between the depth of Invasion and the cytologic feature had limited value.

• 신재생에너지
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• 제7권3호
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• pp.74-82
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• 2011

Because concern on the problem of the limited energy is growing and the wind energy is considered as one of the biggest solutions, the researches on the wind energy and turbine are accomplished vigorously. The simulation tools on the non-linear characteristics of wind turbine system are various and it could describe the non-linear characteristics well but, the tool and methodology to apply non-linear control theory rarely exist. In this paper, the application procedure of sliding mode control theory to 2-DOF non-linear wind turbine system is suggested and the application results of it are also shown as compared with a torque loop control theory.

• 한국임상수의학회지
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• 제17권1호
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• pp.266-269
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• 2000

Tracheal collapse at the thoracic inlet is described in a 4 year-old female yorkshire terrier. The initial presenting signs included coughing, dyspnea, cyanosis and collapse. Diagnosis was based upon the clinical signs, physical examination, plain radiography and fluoroscopy. The collapse was corrected by the aplication of a neumber of modified total ring prostheses (m-TRP) applied to the cervical trachea. Clinical complicatons were minimal and limited to mild, short-term coughing. The present study indicated that m-TRP were easy to apply to tracheal collapse and were able to decrese clinical signs. Therefore, m-TRP may be applied to tracheal collapse as new prostheses.

• 한국국방경영분석학회지
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• 제17권2호
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• pp.44-53
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• 1991

This paper is aimed to develop a Lanchester type combat model for the direct-fire engagement. This model incorporates number of combatants, inter-firing time, detection time by movement, detection probability by the signature of fire, where the inter-firing time and the detection time are assumed to follow a negative exponential distribution. The approach to modeling is as follows : in the process of an engagement, a combatant takes one of the states('observing' state or 'firing' state), a combatant is initially in the observing state, if the combatant detects a target, he changes his state from 'observing' to 'firing' and will cause attrition to the opposing forces. Thus this transition mechanism is embodied into the differential equation form with each transition rate. A limited examination of the validity has been conducted by comparison with the Monte-Carlo simulation model 'BAGSIM', and with a traditional Deterministic Lanchester model.

• Journal of Chest Surgery
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• 제17권2호
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• pp.189-196
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• 1984

Although the conventional methods of cardiopulmonary bypass for open heart surgery have been employed, it has been usual method to repair of congenital heart disease in infancy using deep hypother-mia and circulatory arrest technique. In 1980, we reported total correction of congenital heart disease using surface induced hypothermia-total circulatory arrest and rewarming with limited cardiopulmonary bypass. in 1981, three patients below 10 kilogram, who had ASD and PDA, and two of VSD with pulmonary hypertension were operated on using simple deep hypothermia without cardiopulmonary bypass. During surface cooling, there were no ventricular fibrillation and arrhythmia. There were no difficulties to resuscitate the heart. Postoperative respiratory and neurologic complication were not occurred. Follow up examination for two to three years gave no evidence of cerebral damage due to circulatory arrest.

• The Korean Journal of Pain
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• 제5권2호
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• pp.249-257
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• 1992

It is general knowledge that knee joint pain can be attributed to trauma and degenerative change around the knee joint. However most patients who have suffered from pain or limited range of motion of the knee joint show no definite pathology on X-ray or laboratory examination. We examined 242 patients with knee joint pain and found compression or entrapment of the articular nerve fiber by the tissue around the knee joint resulted in pain in almost all cases. Conclusion: by relieving the compression of the articular nerve fiber with just physical therapy and LASER stimulation on the identified trigger points, in conjunction with NSAIDs, muscle relaxants, were found to be very effective in the treatment of knee joint pain.