Magnetic resonance images of ameloblastoma

Kim, Jae-Duk,Kim, Jin-Soo 대한구강악안면방사선학회 2005 Imaging Science in Dentistry Vol.35 No.4

Purpose : To classify and describe the characteristic features of MRI of some ameloblastoma variants. Materials and Methods : The MR images, CT images, and panoramic radiographs in 5 cases were retrospectively examined as follows. First, the contents of ameloblastomas were devided into two portions of either solid or cystic components on the basis of MR signal intensities. The signal intensity within the solid or cystic portions was classified as homogeneous or heterogeneous. Next, the characteristic internal feature of the lesion on T1W1 or T2WI was described. The signal intensities were classified into low, intermediate, slightly high, high, and strong high signal intensity. Results : Unicystic lesion showed homogeneous high signal intensity (SI) on T2W2 and the rim enhancement of the surrounding area including the mural nodule and the thick wall except the central portion on Gd-T1W1 Solid type revealed heterogeneous and high SI area with strong high SI area on T2W2. On Gd-T1W1, the area corresponding to the low signal spot on T1W1 and the strong high signal spot on T2W1 showed low SI. Hybrid type showed slightly enhanced capsular structures and low SI for the round bony septa and the areas connecting the mixed and cystic lesions on T2W1 and Gd-T1W1. Conclusion : MRI could easily assess the relationship between the mixed and cystic findings in ameloblastoma.

급성 심근허혈에 의해 윤발된 승모판 폐쇄부전의 기전에 관한 실험적 연구

강덕현,송현,송재관,김현숙,이재환,임희영,이재원,박성욱,박승정,송명근 대한순환기학회 1999 Korean Circulation Journal Vol.29 No.8

판막 질환에서의 심근 섬유화 : 심근 조직을 이용한 형태학적 연구 및 혈청 생화학적 지표의 분석

강수진,박덕우,송재관,박경민,송종민,강덕현,한기훈,송현,이재원,주석중,송명근,김정선 대한순환기학회 2004 Korean Circulation Journal Vol.34 No.2

알쯔하이머 환자의 실행증 오류 형태

권재철,나덕렬,김향희,김경문,강연욱 대한신경과학회 1997 대한신경과학회지 Vol.15 No.5

경막내로 투여한 신경전달물질이 통증성 배뇨반사에 미치는 영향

박재식,김덕윤,안동국 大韓泌尿器科學會 1998 Korean Journal of Urology Vol.39 No.8

都市周邊 農村地域의 人口移出現象 : 淸原郡 玉山面의 事例硏究 The Case Study of Oksan

李在德 西原大學校 1984 西原大學 論文集 Vol.13 No.-

In this paper, the writer attempted to identify the problems which came from rural outmigration and to consider the solutions of these problems. It is assumed that these problems are different in every rural areas according to their locational context.The rural areas in the vicinity of city are selected for this study and these are three hamlets in Oksan Myon neighboring Cheongju City (Fig.1).The data were collected by interview with residents in the study area using questionnaire. The analytic procedure for this study is as follows. 1) To see the degree of rural outmigration in the study area,the numbers of migrants and households containing individual migrants are counted and the ratio between migrants and residents are calculated in each study area. 2) The motive,selectivity and destination of outmigration are explained by comparative analysis between migrants and residents in the context of their age, sex, education and income level. 3) From these,the resulting problems are described and some solutions are supposed. In these contexts,the following concluding remarks are made. Study areas experience rural depopulation due to steady outmigration and this reduces the effectiveness of investment for establishments of public facilities and service functions in runal areas.Thus it becomes a hindrance to desirable living of rural residents. Outmigration in study areas also reveal the selectivity of age,sex and education.The age group 20-30 are most highly leaving the rural areas and males are more migratory than females.The more educated,the more migratory. It means the outflow of agricultural labor forces possessing high productivity. Therefore,agriculture is managed by farmers who have low productivity. This results in stagnation of agriculture and low income of rural households in study areas. And thus,economic motive for migration appeared as the most influential one in study area.The stagnation of income results in the delay of agricultural mechanization which seems to be the best method to cope with the lack of labor forces due to financial deficits.Therefore,the rural areas meet with duplicated difficulties. The destination of migrants differ in their motives.These are Seoul Metropolitan Area for occupation and Cheongju City for education respectively. Because Cheongju City cannot offer sufficient employment opportunities,she is not selected as the destination of outmigrants from study areas and commuting to her rarely take place. Thus,I think that the best solutions of these problems are to seek the methods which settle down the rural population in rural areas and which increase the income of farming houscholds.The public investment by government authorities are needed for the improvement of living conditions in rural areas though ineffective.Besides the enhancement of agricultural income through intensive land use,increase of agricultural productivity per unit area,agricultural mechanization etc.,it is desirable in rural areas near the city that rural households get income from nonagricultural sectors to rise their income level.It is possible through that rural residents get a job at neighboring city and commute.For this the regional center which can offer sufficient employment opportunities,public facilities and service functions should be developed within short distance from rural areas.

구리당량 영상작성에 의한 골밀도계측방법의 평가

김재덕 대한구강악안면방사선학회 2000 Imaging Science in Dentistry Vol.30 No.2

Purpose : The effects of step numbers of copper wedge and exposure on the coefficient of determination (r2) of the conversion equation to Cu-equivalent image and on the Cu-equivalent value (mmcu) and it's coefficient of variation measured at each copper step and the mandibular premolar area were evaluated. Method : Digital image analyzing system consisted of scanner, personal computer, and a stepwedge with 10 steps of 0.03 mm copper in thickness as reference material was prepared for quantitative assessment of the bone mineral density. NIH image program was used for analyzing images. Results : The film having moderately high film density showed the discrepancy between the real thickness and the measured Cu-equivalent value of each copper step. The Cu-equivalent image was dependent on the determinational coefficient of the conversion equation than the coefficient of variance of the measured value. Conclusion : Obtaining conversion equation with high coefficient of determination and proper film exposure are supposed to be neccessary for quantitative assessment of bone density. Multiple steps in the range of the corresponding copper thickness to the bone density of the area to be measured should be prepared. (Korean J Oral Maxillofac Radiol 2000 ; 30 : 101-108)

연구실 소고 : 식피와 피판

유재덕 大韓成形外科學會 1990 Archives of Plastic Surgery Vol.17 No.1

14K 및 16K 齒科用 金合金의 硬度 및 微細組織에 關한 硏究

金在道,林時德 대구산업정보대학 1989 논문집 Vol.3 No.-

The purpose of this study was to investigate the variation of micro-vickers hardness and microstructure of dental casting gold alloys manufactured by Korean D Co. Hardness number was measured by micro-vickers hardness tester and microstructure was observed by metallurgical microscope. The results were as follows: 1. Hardness number of experimental group I was 183.62±12.65Hv, hardness number of experimental group Ⅱ was 161,29±9.37Hv, respectively. 2. Hardness number of experimental group I was more approximately 14% than experimental group Ⅱ and both groups were higher hardness number than type Ⅳ gold alloys of K. D. A. specification No. 5. 3. Microstructure of experimental group I was finer structure than experimental group Ⅱ and both groups were existed by dendritic structure and micro porosity.

그래프 모델링 방법에 의한 매니퓰레이터 제어

김덕영,신위재 慶南大學校 附設 工業技術硏究所 1992 硏究論文集 Vol.10 No.-

본 연구에서는 라그랑지-오일러의 동적 모델링 접근방법과 본드 그래프 모델링 기법이 일치함을 보였으며, 매니퓰레이터의 비선형화를 통한 동적 모델링의 비선형성을 거의 무시한 상태에서, 로보트 매니퓰레이터의 P-I 제어기를 구성하였고, 위치와 속도에 대한 추적오차를 관측하기 위하여 ENPORT-7로 시뮬레이션한 결과 본드그래프 모델링 기법이 매니퓰레이터의 동작해석과 제어기 설계에 유용함을 확인하였다. Lagrange-Euler and Newton-Euler modeling methods are required very complicated and tedious process of calculation because it deal with the many variables. Therefore the Bond graph method use in dynamic analysis of multiple-joint manipulator. In this paper, we show that the dynamic modeling approach method of Lagrange-Euler agree to the Bond graph modeling technique and P-I FF controller is designed by Bond graph in order to reduce the following error for position and speed of the Manipulator. In the operating analysis and design on manipulator controller, the usefulness of this modeling method is verified by the ENPORT program simulation.