Point-based surface best fit 알고리즘을 이용한 디지털 치아 모형과 3차원 CT 영상의 중첩 정확도

김봉철,이채은,박원서,강정완,이충국,이상휘,Kim, Bong-Chul,Lee, Chae-Eun,Park, Won-Se,Kang, Jeong-Wan,Yi, Choong-Kook,Lee, Sang-Hwy 대한구강악안면외과학회 2008 대한구강악안면외과학회지 Vol.34 No.5

Purpose: The goal of this study was to develop a technique for creating a computerized composite maxillofacial-dental model, based on point-based surface best fit algorithm and to test its accuracy. The computerized composite maxillofacial-dental model was made by the three dimensional combination of a 3-dimensional (3D) computed tomography (CT) bone model with digital dental model. Materials and Methods: This integration procedure mainly consists of following steps : 1) a reconstruction of a virtual skull and digital dental model from CT and laser scanned dental model ; 2) an incorporation of dental model into virtual maxillofacial-dental model by point-based surface best fit algorithm; 3) an assessment of the accuracy of incorporation. To test this system, CTs and dental models from 3 volunteers with cranio-maxillofacial deformities were obtained. And the registration accuracy was determined by the root mean squared distance between the corresponding reference points in a set of 2 images. Results and Conclusions: Fusion error for the maxillofacial 3D CT model with the digital dental model ranged between 0.1 and 0.3 mm with mean of 0.2 mm. The range of errors were similar to those reported elsewhere with the fiducial markers. So this study confirmed the feasibility and accuracy of combining digital dental model and 3D CT maxillofacial model. And this technique seemed to be easier for us that its clinical applicability can good in the field of digital cranio-maxillofacial surgery.

적색안료인 α-Fe₂O₃와 투명 유전체의 반응

김봉철,한용수,송윤호,서경수,이진호,이남양,박이순,이병교,Kim, Bong-Chul,Han, Yong-Soo,Song, Yoon-Ho,Suh, Kyung-Soo,Lee, Jin-Ho,Lee, Nam-Yang,Park, Lee-Soon,Lee, Byung-Kyo 한국세라믹학회 2002 한국세라믹학회지 Vol.39 No.3

적색 칼라 필터 재료인 ${\alpha}-Fe_2O_3$가 고온 제조 공정을 거치는 동안 화학적인 안정성에 관해서 연구한 것이다. PDP(Plasma Display Panel)에 있어서 통상적으로 칼라 필터 층의 위에 사용되고 있는 투명 유전체의 경우는 광의 투과도를 높이기 위하여 ZnO를 첨가한다. ZnO가 포함되어 있는 유전체의 경우는 500$^{\circ}$C 이상에서 ${\alpha}-Fe_2O_3$의 열적 안정성을 감소시켜 칼라 필터로서의 기능을 완전히 상실하게 되어 투명하게 된다. 반면에 ZnO가 포함되지 않는 투명 유전체의 경우는 ${\alpha}-Fe_2O_3$가 적색의 색상을 유지하면서 칼라필터로서의 기능을 유지하고 있었다. ${\alpha}-Fe_2O_3$가 칼라 필터로 기능을 유지하기 위해서는 ${\alpha}-Fe_2O_3$와 접촉하는 투명 유전체는 ZnO가 포함되지 않는 투명 유전체를 사용하여 1차 보호막을 형성한 후 그 위에 ZnO가 포함된 투명 유전체층을 형성하면 적색 칼라 필터가 색상을 유지하게 된다. We searched thermal stability of ${\alpha}-Fe_2O_3$ using red color filter for display. In the PDP(Plasma Display Panel), the color filter layer is lied normally between front glass and transparent dielectric materials, so it might be needed to study the reaction of ${\alpha}-Fe_2O_3$ and transparent dielectric materials. The transparent dielectric materials containing ZnO has good transparency. Red colorlayer of ${\alpha}-Fe_2O_3$ contacted with dielectric material layer containing ZnO is changed to colorlessness over 500$^{\circ}$C because ZnO defuse ${\alpha}-Fe_2O_3$, the dielectric materials without ZnO, however, maintain red color at the same condition. We suggest that a layer contacting with ${\alpha}-Fe_2O_3$ red color layer has to lie with transparent dielectric materials without ZnO, then the materials containing ZnO is coated over to get color of ${\alpha}-Fe_2O_3$ for red color filter

악교정 수술을 위한 디지털 모형 수술의 정확성 평가

김봉철,박원서,강연희,이충국,유형석,강석진,이상휘,Kim, Bong-Chul,Park, Won-Se,Kang, Yon-Hee,Yi, Choong-Kook,Yoo, Hyung-Suk,Kang, Suk-Jin,Lee, Sang-Hwy 대한악안면성형재건외과학회 2007 Maxillofacial Plastic Reconstructive Surgery Vol.29 No.6

The accuracy of model surgery is one of important factors which can influence the outcome of orthognathic surgery. To evaluate the accuracy of digitalized model surgery, we tried the model surgery on a software after transferring the mounted model block into a digital model, and compared the results with that of classical manual model surgery. We could get the following results, which can be used as good baseline analysis for the clinical application. 1. We made the 3D scanning of dental model blocks, and mounted on a software. And we performed the model surgery according to the previously arranged surgical plans, and let the rapid prototyping machine produce the surgical wafer. All through these process, we could confirm that the digital model surgery is feasible without difficulties. 2. The digital model surgery group (Group 2) showed a mean error of $0.0{\sim}0.1mm$ for moving the maxillary model block to the target position. And Group 1, which was done by manual model surgery, presented a mean error of $0.1{\sim}1.2mm$, which is definitely greater than those of Group 2. 3. Remounted maxillary model block with the wafers produced by digital model surgery from Group 2 showed the less mean error (0.2 to 0.4 mm) than that produced by manual model surgery in Group 1 (0.3 to 1.4 mm). From these results, we could confirm that the digital model surgery in Group 2 presented less error than manual model surgery of Group 1. And the model surgery by digital manipulation is expected to have less influence from the individual variation or degree of expertness. So the increased accuracy and enhanced manipulability will serve the digital model surgery as the good candidate for the improvement and replacement of the classical model surgery, if careful preparation works for the clinical adjustment is accompanied.

EPS 적용을 위한 SRM의 효율향상 설계 및 특성

김봉철(Bong-Chul Kim),안진우(Jin-Woo Ahn) 전력전자학회 2004 전력전자학술대회 논문집 Vol.- No.-

This paper presents a design and characteristics analysis of an SRM drive for EPS application. A rack mounted EPS system is considered in this paper. In the unrestricted design conditions, motor parameters are determined for sufficient torque and speed with some restrictions. For the smooth torque generation and simple circuit of power system, 12/8 motor drive is considered. With FEM and magnetic circuit analysis, redesigned motor is simulated to meet the requirement of specifications. Effectiveness of the suggested SRM drive for EPS application is verified by redesigned motor drive tests.

고등학생들의 원자력 인식구조에 대한 언어 연결망 분석

김봉철(Bong-Chul Kim),정운관(Woon-Kwan Chung),최명일(Myung-Il Choi) 한국콘텐츠학회 2015 한국콘텐츠학회논문지 Vol.15 No.7

이 연구는 언어 연결망 분석을 통해 고등학교 학생들이 원자력에 대해 어떤 인식구조를 갖고 있는가를 파악하기 위한 것이다. 6대 광역도시에 소재하는 고등학생 250명을 대상으로 설문조사를 실시한 결과, 출현빈도가 높은 단어들은 발전소(87회), 일본(71회), 위험(59회), 후쿠시마(59회), 방사능(56회), 에너지(47회), 영광(37회), 전기(30회), 체르노빌(29회), 폭발(25회) 등인 것으로 나타났다. 한편, 원자력 수용성이 높은 집단과 낮은 집단으로 구분하여 차이를 분석한 결과, 수용성이 높은 집단은 방사능(25회), 후쿠시마(23회), 에너지(21회), 일본(21회), 발전소(20회), 위험(17회), 영광(16회), 핵(14회) 등이, 수용성이 낮은 집단은 발전소(40회), 일본(31회), 위험(29회), 후쿠시마(23회), 방사능(17회), 에너지(16회), 영광(16회), 체르노빌(15회) 등의 출현빈도가 높은 것으로 나타났다. 이러한 결과를 바탕으로, 원자력과 관련한 대국민 커뮤니케이션은 공중 세분화와 이에 따른 적절한 접근이 필요하다는 사실을 확인할 수 있었다. This paper investigated how high school students perceive on nuclear power applying semantic network analysis. The total number of 250 high school students in 6 metropolitan areas responded to the survey. Results indicate that the word which most frequently appeared is ‘Nuclear plant’ (87 times) following by ‘Japan’ (71 times), ‘Danger’(59 times), ‘Fukushima’ (59 times), ‘Radioactivity’ (56 times), ‘Energy’ (47 times), ‘Youngkwang’ (37 times), ‘Electricity’ (30times), ‘Chernobyl’ (29 times), ‘Explosion’ (25 times). For students in higher acceptance level of nuclear ‘Radioactivity’ (25 times) was most frequently showed up following by ‘Fukushima’ (23 times), ‘Energy’ (21 times), ‘Japan’ (21 times), Nuclear plant’ (20 times), ‘Danger’ (17 times), ‘Youngkwang’ (16 times). For student in lower acceptance level of nuclear, the word of ‘Nuclear plant’ (40 times) most frequently appeared following by ‘Japan’ (31 times)’, ‘Danger’ (29 times), ‘Fukushima’ (23 times), ‘Radioactivity’ (17 times), ‘Energy’ (16 times), ‘Youngkwang’ (16 times), ‘Chernobyl’ (15 times).

학교 폭력에 대한 낙관적 편견과 제3자 효과

김봉철 ( Bong Chul Kim ),최명일 ( Myung Il Chio ),이동근 ( Dong Geun Lee ) 한국PR학회 2006 PR연구 Vol.10 No.2

The optimistic bias and the third-person effect are similar concepts concerned with people`s perceptual bias. But these two concepts have been studied separately in different fields so far. The current research is about the relationship between these two concepts. Opinion survey of 428 high school students revealed the optimistic bias and the third-person effect. These two perceptual biases showed statistically significant relationships respectively with the psychological distance. The third-person effect was proportional to psychological distance, but the optimistic bias was not proportional to psychological distance. In the meantime, the self-esteem was proportional to the optimistic bias whereas the third-person effect did not show statistically significant relationship with the self-esteem. Lastly, the optimistic bias and the third-person effect regarding school violence did not show any relationship with each other.

The mainstream of the RTA case‐law in the WTO Dispute Settlement System

김봉철(Kim, Bong-Chul) 원광대학교 법학연구소 2009 圓光法學 Vol.25 No.2

지역무역협정은 WTO의 출범시기부터 각국의 체결이 급증하여, 최근에는 국제무역규범의 대안으로까지 평가되기도 한다. 이러한 상황 속에서, WTO는 회원국들의 지역무역협정 체결에 대한 규제를 보다 강화하기 위해 지역무역협정위원회의 설치를 비롯한 다양한 방법을 시도하고 있다. 지역무역협정위원회의 역할에 더하여, WTO 분쟁해결절차에서 지역무역협정 관련 분쟁의 해결을 통한 일종의 판례법을 축적하여 지역무역협정에 관련한 해석의 기준을 마련하는 것도 WTO 체계 내에서 지역무역협정의 규율을 강화하기 위한 방법이 될 수 있다. WTO 분쟁해결절차에서는 몇 차례의 지역무역협정 관련 사례가 논의된 바 있다. 이러한 사례들 중 많은 경우가 FTA 또는 관세동맹과 같은 형태의 지역무역협정과 세이프가드 적용에 관한 것이었다. 또한 사례들의 분석 결과, 분쟁해결기구는 상당수의 분쟁에 있어서 지역무역협정에 관한 논점을 적극적으로 해결하기 보다는 이른바 ‘병행주의’(Parallelism) 등과 같은 전혀 다른 이론을 적용하여 가급적 피하려고 한다는 점을 발견할 수 있다. 이러한 내용은, 지역무역협정에 관한 WTO 규범들의 해석에 있어서 모호한 부분을 해결하기 위해 축적된 ‘WTO 판례법’이 이용될 수 있을 것이라는 기대에는 미치지 못하는 결과이다. 지역무역협정에 관한 WTO의 적극적인 규제와 분쟁 발생의 방지를 위해서는, 이와 관련된 판례의 축적이 더욱 요구된다. 아울러 분쟁해결절차에서 지역무역협정의 논의가 보다 적극적으로 진행되어야 할 것이다.

용존공기부상 공정 적용을 통한 미세먼지 오염수 무방류 시스템 성능 평가

김봉철(Kim, Bong Chul),박찬규(Park, Chan Gyu) 대한토목학회 2020 대한토목학회 학술대회 Vol.2020 No.10

커피전문점 브랜드이미지와 구매의도의 관계에서 혼잡지각의 조절효과

김봉철(Kim, Bong-Chul),최풍운(Choi, Poong-Woon) 한국서비스산업학회 2012 서비스산업연구 Vol.9 No.2

태국 기업법상 설립규정에 관한 비교법적 고찰

김봉철(KIM Bong-Chul),이준표(LEE Joon-Pyo) 한국태국학회 2011 한국태국학회논총 Vol.18 No.1

Thailand is newly industrialised and emerging in the world economy these days. After the Asian Financial crisis, the economy of the Southeast Asian country is recovering with the help of the IMF and several internal economic reforms. The legal reforms on enterprises is also related with the situation. One of the basic laws in this field is the Civil and Commercial Code section 22(Articles 1012 to 1273) which regulates partnerships or companies. The Public Limited Company Code also regulates these types of enterprises. There are three general types of partnerships in Thailand: Unregistered ordinary partnerships, Registered ordinary partnerships and Limited partnerships. These are governed by the Thai Civil and Commercial Code. There are two types of limited companies: private limited companies and public limited companies. The first is governed by the Civil and Commercial Code and the second is governed by the Public Limited Company Act. A public limited company governed by the Public Limited Company Code is one established for the purpose of offering the sale of shares to the public. The procedure for incorporating a public limited company is similar to that of a private limited company in registration requirements and shareholder liability. However, there are some differences between the two types on several requirements. Thailand is an interesting country for start a business in ASEAN. In 2008, the Thai Civil and Commercial Code and Public Limited Company Code was changed to simplify the incorporation of a limited liability company. In spite of these improvements, it may be asked whether these measures can actually guarantee the practice effect of laws. Hence, it is necessary for Thai enterprise law that should be established in incorporation procedure.