Formulation of a reference coordinate system of threedimensional head & neck images : Part Ⅱ. Reproducibitity Ⅱ부 수평기준면과 정중사상면의 재현성

Kim, Nam-Kug,Park, Jae-Woo,Chang, Young-Il 대한치과교정학회 발행 2005 대한치과교정학회지 Vol.35 No.6

This study was performed to investigate the reproducibility of the horizontal and midsagittal planes, and to suggest a stable coordinate system for three-dimensional (3D) cephalometric analysis. Eighteen CT scans were taken and the coordinate system was established using 7 reference points marked by a volume model, with no more than 4 points on the same plane. The 3D landmarks were selected on V works (Cybermed Inc., Seoul, Korea), then exported to V surgery (Cybermed Inc., Seoul, Korea) to calculate the coordinate values. All the landmarks were taken twice with a lapse of 2 weeks. The horizontal and midsagittal planes were constructed and its reproducibility was evaluated. There was no significant difference in the reproducibility of the horizontal reference planes. But, FH planes were more reproducible than other horizontal planes. FH planes showed no difference between the planes constructed with 3 out of 4 points. The angle of infersection made by 2 FH planes, composed of both Po and one Or showed less than 1° difference. This was identical when 2 FH planes were composed of both Or and one Po. But, the latter cases showed a significantly smaller error. The reproducibility of the midsagittal plane was reliable with an error range of 0.61 to 1.93° except for 5 establishments (FMS-Nc, Na-Rh, Na-ANS, Rh-ANS, and FR-PNS). The 3D coordinate system may be constructed with 3 planes; the horizontal plane constructed by both Po and right Or; the midsagittal plane perpendicular to the horizontal plane, including the midpoint of the Foramen Spinosum and Nc; and coronal plane perpendicular to the horizontal and midsagittal planes, including point clinodale, or sella, or PNS. 본연구는 삼차원 두부 영상을 위치시키기 위한 좌표계를 구성하는 방법에 대한 제안하기 위해, CT data에서 기존의 두부방사선 계측사진에서 쓰이는 점들을 선정하고, 이를 바탕으로 수평, 수직평면의 안정성을 조사하였다. 서울대학교 치과병원에 내원한 환자 18명의 CT자료를 채득하였으며, 모든 환자는 서울대학교 병원 진단방사선과에서 촬영하였다. (Somatom Plus 4: Siemens, Eriange, Germany). V works for surgery 4.0 (Cybermed Inc., Seoul, Korea)을 이용하여 3차원 좌측표를 선정하고, 계측점을 선택하였다. 좌표축을 동일하게 설정하기 위해 7개의 점(reference point)을 4·4·2 pixel size의 voxel로 따로 표시하였다. 계측점을 선정한 후 V surgery (Cybermed Inc., Seoul, Korea)에서 각 점의 좌표값을 추출하였다. 각각의 점들은 2회 반복 선정한 후 점들을 조합하여 수평, 수직평면의 재현성을 평가한 결과 다음과 같은 결론을 얻었다 수평 기준면의 재현도는 S-CI평면을 제외하고는 통계적으로 유의한 차이를 보이지 않았으나, 사잇각은 FH평면이 가장 작게 나타났다. FH평면은 Po과 Or중 어느 3점을 선택하더라도, 통계적으로 유사한 재현도를 보였다. FH1과 FH2의 사잇각과 FH3과 FH4의 사잇각은 1° 이하의 적은 오차를 보이며, FH3과 FH4의 사잇각이 통계적으로 더 작은 차이를 보였다. 정중시상면의 재현도는 FMS-Nc, Na-Rh, Na-ANS, Rh-ANS, FR-PNS를 기준으로 설정한 경우를 제외하면, 0.61~1.93° 의 양호한 값을 보였다. 이상의 결과에 의하면 공간에서 정의되는 평면의 재현도는 평면을 정의하는 점 자체의 식별오차뿐 아니라, 각 점의 위치관게에도 영향을 받는 것을 알 수 있었다. 따라서, 안정적인 3차원 기준좌표계를 구성하려면 양측 Po과 편측 Or으로 구성되는 평면을 수평기준면으로, 수평면에 수직이고, Foramen Spinosum의 중점과 Nc를 포함하는 평면을 수직기준면으로, 수평면과 수직면에 수직이고, clinoidale나 sella, PNS를 지나는 평면을 전두면으로 설정하는 것이 바람직할 것으로 생각된다.

우라늄 투여후 간조직에서의 효소활성도의 변화

김국찬,이강석,김진규,김인규,박효국,천기정,김상복 대한방사선 방어학회 1993 방사선방어학회지 Vol.18 No.2

우라늄 피폭후 효소활성도가 내부피폭의 biomarker로서의 가능성을 연구하기 위하여 수서생물인 잉어9Caprinus carpio)의 복강내 우라늄 투여시 간조직에서 일어나는 여러가지 효소계의 변화를 조사하였다. 이러한 효소활성도의 변화는 우라늄 내부피폭의 biomarker로서 가능성을 가지고 있으며 연구결과는 다음과 같다. 1) 6일째까지 우라늄을 주사하여 적출한 간에서의 전체단백질량은 계속 감소하고 있다. 2) 세포내의 lysosome내에 함유하고 있는 acid protease와 β-glucuronidase의 활성도는 6일째 투여후까지 활성도가 감소하고 있다. 3) Alkaline phosphatase의 경우 6일째 우라늄 투여후까지 증가하고 있으며 반대로 acid phosphatase의 경우 6일째 우라늄 투여후까지 활성도가 급격히 증가하였고 glutamate oxaloacetate transaminase의 활성도는 완만하게 증가하고 있다. 4) Creatine kinase의 활성도는 완만한 감소를 보이고 있으며 malate dehydrogenase는 첫번 우라늄 투여후에 활성도가 급격히 감소하였고 3일째 우라늄 투여후에는 활성도가 거의 나타나지 않았다. We examined various enzyme activity changes by intraperitioneal injection uranium in the carp liver. These enzyme activity changes can be used as biochemical indicators of internal exposure to uranium. The results were followings ; 1) Total protein concentration decreased by intraperitoneal injection in the carp liver. 2) Lysosomal acid protease and β-glucronidase activities increased in the liver until sixth intraperitoneal injection of uranium, but lysosomal acid phosphatase activities decreased in the liver until the sixth injection of uranium. 3) Alkaline phosphatase activities sharply increased and Glutamate oxaloacetate Transaminase activities steadily decreased in the liver until the sixth injection of uranium. 4) Creatine %kinase activities steadily decreased and malate dehydrogenase activities sharply decreased in the liver after the primary injection of uranium. Any malate dehydrogenase activities was not detected after sixth injection of uranium.

사이클하중을 받는 철근콘크리트 보-기둥 접합부의 거동에 관한 연구

장극관 서울産業大學校 1996 논문집 Vol.44 No.1

In the design of ductile moment-resisting frames "DMRFs" following the strong column-weak beam design philosophy, it is desirable that the joint and column remain essentially elastic in order to insure proper energy dissipation and lateral stability of the structure. The joint has been identified as the "weak link" in DMRFs because any stiffness or strignth deterioration in this region can lead to substantial drifts and the possibility of collapse due to P-delta effects. Moreover, the engineer is faced with the difficult task of detailing an element whose ssize is determined by the framing members, but which mest resist a set of loads very different from those used in the design of the beams and columns. For 2/3-scale beam-column-slab joint assemblies were designed according to existing code requirements of ACI 318-89, representing interior joints of DMRFs with reinforced high strength concrete. The influence on aseismic behavior of beam-column joints due to monolithic sbal, has been investigated.

드릴 공구의 응력 해석을 위한 유한요소법의 적용

김국원 순천향대학교 부설 산업기술연구소 2004 순천향 산업기술연구소논문집 Vol.10 No.2

Drilling process is one of the most common, yet complex operations among manufacturing processes. The performance of a drill is largely dependent upon drilling forces. Many researches focused on the effects of drill parameters on drilling forces. In this paper, the integration of CAD/CAE for the drill tool is performed. The stresses occurring in drilling process are analyzed by finite element method. The analytic drilling forces considering the drill parameters and drilling conditions are used. With ANSYS, geometric modeling and mesh generation of drill is performed automatically. From the study, the optimal drill tool design and the drilling condition determination may be achieved.

고무재료의 경도와 변형률 에너지 함수에 관한 연구

김국원 순천향대학교 부설 산업기술연구소 2001 순천향 산업기술연구소논문집 Vol.7 No.1

Up to now, several mathematical theories based on strain energy functions have been developed for rubber materials. These theories, coupled with the finite element method, can be used very effectively by engineers to analyze and design rubber components. However, due to the complexities of the mathematical fomulations and the lack of general guidelines available for the analysis of rubber components, it is a formidable task for a engineer to use these rubber theories. In this paper, a simple method for predicting the strain energy function (Neo-Hookean model and Mooney-Rivlin model) without any experiment is discussed. This method is based on an empirical equation to estimate elastic modulus from hardness. Compared with uniaxial tension tests and Mooney-Rivlin model from the measured data, the usefulness of this method is confirmed.

寶城소리 沈淸歌 : 問題點·解釋試論

李菊子 全北大學校 國語國文學會 1982 國語文學 Vol.24 No.-

무인감시시스템 구현을 위한 이동체 인식 알고리즘에 관한 연구

장국렬,방만원,박진홍,박순영 木浦大學校 情報産業硏究所 1996 情報産業硏究誌 Vol.4 No.-

In this paper, an effective algorithm which can detect moving objects from the image sequences and classify an intruder from other moving objects is presented for an implementation of unmanned surveillance system. The proposed algorithm uses a stick figure model for features of the moving object since the stick figure model can be represent the characteristics of the moving objects. The stick figure model is extracted by applying the thining algorithm to the binary difference image between the reference and the image of a moving object. The computer simulation is carried out to analyze the performance of the proposed algorithm. The results show that the algorithm can discriminate a moving person and a moving animal with high degree of reliability.

日東壯遊歌 硏究 : 作家를 中心으로

金國昭 명지어문학회 1976 明知語文學 Vol.8 No.-

유한요소법을 이용한 DC 브러쉬 모터의 동특성 해석

김국원 순천향대학교 부설 산업기술연구소 2001 순천향 산업기술연구소논문집 Vol.7 No.2

In this paper, described is a research on the dynamic characteristics of DS brush motor finite element method. A impact test is performed to obtain the natual frequencies, which valuate the usefulness of the finite element analysis. From the study, It is thought that this finite element model can be applicable for designing a new motor with improvement in dynamic characteristics.

동아대학교박물관 소장 朱敬一肖像畵

金國寶 동아대학교 박물관 2000 考古歷史學志 Vol.16 No.-