• Imaging Science in Dentistry
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• v.39 no.2
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• pp.99-102
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• 2009

Adenomatoid odontogenic tumor (AOT) is a tumor of odontogenic epithelium with varying degrees of inductive changes in the connective tissue. The common radiographic appearance of AOT is a unilocular radiolucency associated with an unerupted tooth. Detectable radiopacities have been reported in many cases. We present a case of AOT in a 9-year old-female patient. Cystic lesion with numerous, punctuate radiopaque foci was observed on the anterior region of the mandible. These radiopacities were situated mostly on the buccal side of impacted tooth on the multi-planar images of cone beam computed tomograph. Characteristic duct like structures and amyloid like material were observed on histopathologic finding. (Korean J Oral Maxillofac Radiol2009; 39 : 99-102)

• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.28 no.1
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• pp.299-309
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• 1998

This case was diagnosed as multiple cementoosseous dysplasia on the basis of clinical & radiological features but was diagnosed as ossifying fibroma on the basis of histopathological feature. The histopathologic features of the multiple cementoosseous dysplasia and cementoossifying fibroma have common features of cementum, fibrous network and bone. Multiple cementoosseous dysplasia is reactive lesion and shows restricted lesion size, occurred on anterior and posterior tooth of the mandible and needs no treatement except periodic follow up. But Cementoossifying fibroma is the true neoplasm and grows continuously and needs surgical removal. The final diagnosis of the multiple cementoosseous dysplasia requires good correlation of the clinical, histopathological, and radiological features.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1999.11a
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• pp.402-405
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• 1999

The Study of this paper is to establish the optimum fabricating condition of specimens using Vapor Deposition Polymerization Method which belongs to a mode of preparation of functional organic thin films with dry process and to develop thin film type humidity sensor which has good humidity sensitive Characteristics. Scanning electron microscopy Atomic force microscopy were used to analyze the characteristics of thin film and the basic structure of the humidity sensor is a parallel capacitor which consists of three layers of Al/PI/Al. The characteristics of fabricated samples were measured under various conditions and obtained linear characteristics in the range of 20∼80%RH independent of temperature change and low hysteresis characteristics.

• Journal of radiological science and technology
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• v.13 no.1
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• pp.3-9
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• 1990

A study was carried out to investigate the technical factors and the patient dose (entrance and absorbed dose) in chest P-A radiography based on the 86 hospitals in Seoul from July 1 to July 30, 1989. As a result of this study, main finding were as follow : 1. 51.2% of the surveyed hospitals made use of $60{\sim}69\;kVp$ as tube voltage in chest radiography 2. The majority of the surveyed(88.3%) have the use of $6{\sim}20\;mAs$ as tube current-time. 3. Percentage absorbed doses in patient were showed more than 90 percent in every tube voltage. 4. Object densities were all much the same in all tube voltages. 5. 48.8% of surveyed entrance doses ranged from $100\;{\mu}Sv$ to $190\;{mu}Sv$, and the mean dose was $158\;{\mu}Sv$.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.20 no.10
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• pp.883-890
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• 2010

According to torsional vibration characteristic of a tunable dual stiffness type clutch(TDSTC) in auto-transmission, the input shaft system have occurred breakdown for the duration cycle and over-vibration happened on vehicle at specific condition. This paper introduces the improvement of the torsional vibration of input shaft and the vehicle vibration by tuning of the TDSTC.

• Journal of Yeungnam Medical Science
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• v.12 no.2
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• pp.405-411
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• 1995

Lichenoid drug eruption is lichenoid skin eruptions caused by certain drugs and compounds, and can be identical or similiar to lichen planus. A 75-year-old woman who had taken antituberculosis medication(INH, ethambutol, rifampin) for 4 months developed pruritic generalized erythematous papular eruptions on the trunk and extremities, alopecia and nail dystropy. Histopathologic findings were hyperkeratosis, hypergranulosis, hydrophic degenaration of basal layer, band like lymphohistiocytic infiltration in the upper dermis and perivascular lymphohistiocytic infiltration in the deep dermis. She was treated with systemic corticosteroid, and then skin lesion were slightly improved. After termination of antituberculosis medication, skin lesions were markedly improved with residual hyperpigmentation. Alopecia and nail dystrophy were also improved.

• Proceedings of the Korean Nuclear Society Conference
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• 1996.11b
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• pp.521-526
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• 1996

원자력 발전소 내의 1차계통수에 존재하는 부식생성물과 노심에서 방사화된 여러 핵종들의 종류와 그 양에 대해서 CRUDSIM/MIT모형을 이용해서 분석하였다. 고리 4호기의 차계통수내의 수화학 조건을 이용하여 CRUDSIM/MIT모형에 적용하고 그 결과를 냉각수의 Activity자료와 증기 발생기의 Activity자료와 서로 비교 분석하였고, 노심과 증기발생기의 Crud양과 Activity를 예상하였다. 이 모형의 주요 인자인 $\beta$$_{c}$와 $\beta$$_{a}$ 값을 증기발생기의 Activity측정자료에 의해서 구하였다. 그리고 발전소 운전 중에 증기 발생기와 냉각수의 Activity각 최소화 할 수 있는 최적 조건 범위도 냉각수의 온도, pH, 수소농도등을 변화시켜서 구하였다. 고리4호기에 이 모형을 적용할 때 입력 자료에서, Activation Factor와 Recoil Release 등의 인자와 증기 발생기의 방사선양과 핵연료 표면의 Crud양을 구할 수 있으면 더욱 정확한 결과 값들을 얻을 수 있다.

• Proceedings of the Korea Contents Association Conference
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• 2019.05a
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• pp.323-324
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• 2019

오늘날 관광업은 나날이 한 도시의 중요한 경제 수입 업종이 되고 있으며, 관광업은 지방의 경제 발전에 대체적인 작용을 한다. 사인시스템에서 중요한 공공시설로서, 없어서는 안 되는 작용을 하고 있다. 관람객들은 사인시스템을 통해 목적지를 찾는 데 필요한 시간을 단축할 수 있고, 관광지에 대한 전반적인 인상도 높일 수 있다. 고대 고성 안내 사인시스템에 대한 연구와 완벽을 통해서 옛 고성로 하여금 더욱 좋은 개발 기회를 얻게 하다. 이곳을 찾은 사람들이 역사와 문화에 대해 더 잘 알게 해 준다고 말했다. 본 논문의 연구 대상은 중국 남북의 역사문화관광지 중에서 선발한 AAAA급 이상의 관광지이다. 본 연구의 연구 대상으로 선정된 4개 관광지는 리장고성, 관도고성, 선양고궁. 첫째, 관련 문헌을 통해 사인디자인과 관련된 요소를 파악, 이들 요소를 바탕으로 설문 조사의 관련 문항을 제작했다. 둘째, 관광지마다 현장조사를 하고 관련 사진을 수집해 설문조사의 기초 자료로 활용했다. 네 개의 관광지의 사인시스템에 대해 설문조사를 실시하다. 셋째, 설문조사 결과를 집계한다.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2020.11a
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• pp.90-91
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• 2020

Utilization of upgraded fine fly ash in cement-based materials has been proved by many researchers as an effective method to improve compressive strength of cement based materials at early ages. The addition of fine fly ash has introduced dilution effect, enhanced pozzolanic reaction effect, nucleation effect and physical filling effect into cement-fly ash system. In this study, an integrated reaction model is adpoted to quantify the contributions from cement hydration and pozzolanic reaction to compressive strength. A modified model related to the physical filling effect is utilized to calculate the compressive strength increment considering the gradual dissolution of fly ash particles. Via combination of these two parts, a numerical model has been proposed to predict the compressive strength development of fine fly ash mortar considering fly ash fineness. The reliability of the model is validated through good agreement with the experimental results from previous articles.

• Korean Journal of Poultry Science
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• v.19 no.1
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• pp.35-45
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• 1992

This study was carried out to investigate the effect of different dose of 312nm UV irradiation on ash and phosphorus contents in metatarsus of broiler chicks, whose dorsal skins were exposed to the UV light. Day old Hubbard line broiler chicks were fed with vitamin D deficient diet for 3 weeks and the defeathered dorsal skins were exposed to different dise (0.32, 0.65, or 0.98 J/$\textrm{cm}^2$) of 312nm UV light. The metatarsus bones were collected on 0, 1, 2, 3, 4 or 5 days after irradiation and defatted, dried, ashed and dissolved in 6N-HCI. The P concentrations were determined by spectrophotometry. When the 0.32 J/$\textrm{cm}^2$ dose was applied, the ash contents in metatarsus bones o( chicks were 42, 46 and 40% on 0, 1 and 3 days after irradiation, respectively. The maximum level, 46% was appeared at 2 days after exposure as 0.65 J/$\textrm{cm}^2$ was treated. When 0.98 J/$\textrm{cm}^2$ irradiation was applied, the high concentrations, 47 and 47% were shown on 1 and 2 days after irradiation, respectively. The 0.98 J/$\textrm{cm}^2$ among three levels of dose increased the most amount of ash in metatarsus bone. In respect to the P content in the chick bone the increased level, 19.4% was shown on 3 days after UV treatment with 0.32 J/$\textrm{cm}^2$. The maximum levels, 18.1 and 20.0% were present on 3 and 2 days after exposure to the 0.65 and 0.98 J/$\textrm{cm}^2$ of UV dose, respectively. It was shown that the higher dose of UV irradiation increased the more P concentration in matatarsus of chicks and the production rate was faster than those from 0.32 and 0.65 J/$\textrm{cm}^2$ treatments.