A Registration Method between Optical Tracker and Depth Camera Using Deep Learning

Jin Kim(김진),Da-El Kim(김다엘),MinHyuk Choi(최민혁),Su Yang(양수),Se-Ryong Kang(강세룡),So-Young Chun(천소영),Ji-Yong Yoo(유지용),Siyeon Noh(노시연),Sehum Kim(김세훈),Won-Jin Yi(이원진) 대한전자공학회 2022 대한전자공학회 학술대회 Vol.2022 No.4

Hough변환을 이용한 정자의 형태학적 특성 분석방법에 관한 연구

박광석,이원진,백재승,Park, Kwang-Suk,Yi, Won-Jin,Paick, Jae-Seung 대한의용생체공학회 1996 의공학회지 Vol.17 No.1

Hough변환을 이용하여 정자의 행태학적 특성을 분석하는 새로운 방법을 개발하였다. 이 방법은 정자의 머리부분이 주위의 배경과 밝기의 차이를 갖는다는 특성과 함께 그 형태가 타원에 근접한다는 특성에 근거하고 있다. 정자의 머리부분은 타원을 나타내는 5개의 파라메터로 표현되고, 최적의 파라메터 값이 반복적인 Hough 변환에 의하여 검출된다. 일차적으로 정자가 있는 영역을 선택한다. Hough변환을 이용한 계산을 가능하게 하기 위하여 Hough변환된 공간의 크기를 최소한으로 줄이고, 검출된 오차가 최소화되는 방향으로 검사영역을 이동 시켜가며 최적의 파라메터들을 도출한다. 형태학적 특성을 나타내는 지표들은 정자의 형태를 나타내는 타원의 다섯개 파라메터들로부터 계산된다. A new analytic method has been developed for the analysis of sperm morphology using Hough transform. This method is based on the characteristic that sperm heads have elliptic shape in addition to the density difference with the background Sperm heads are represented in elliptic form with five parameter, and the optimal parameters are estimated by iterative Hough transform. To reduce processing time practically, we restricted the transformed space in minimum volume and moved the searching volume to the maximum gradient for the estimated error. Morphological parameters were calculated from estimated sperm head boundaries without further processing.

하악 제1대구치의 치근 만곡에 영향을 주는 요인

최항문,이원진,허민석,이삼선,김정화,최순철,박태원,Choi Hang-Moon,Yi Won-Jin,Heo Min-Suk,Lee Sam-Sun,Kim Jung-Hwa,Choi Soon-Chul,Park Tae-Won 대한영상치의학회 2006 Imaging Science in Dentistry Vol.36 No.1

Purpose : To find the cause of root curvature by use of panoramic and lateral cephalometric radiograph. Materials and Methods : Twenty six 1st graders whose mandibular 1st molars .just emerged into the mouth were selected. Panoramic and lateral cephalometric radiograph were taken at grade 1 and 6, longitudinally. In cephalometric radio graph, mandibular plane angle, ramus-occlusal plane angle, gonial angle, and gonion-gnathion distance (Go-Gn distance) were measured. In panoramic radio graph, elongated root length and root angle were measured by means of digital subtraction radiography. Occlusal plane-tooth axis angle was measured, too. Pearson correlations were used to evaluate the relationships between root curvature and elongated length and longitudinal variations of all variables. Multiple regression equation using related variables was computed. Results : The Pearson correlation coefficient between curved angle and longitudinal variations of occlusal plane-tooth axis angle and ramus-occlusal plane angle was 0.350 and 0.401, respectively (p<0.05). There was no significant correlation between elongated root length and longitudinal variations of all variables. The resulting regression equation was $Y=10.209+0.208X_1+0.745X_2$ (Y: root angle, $X_1$: variation of occlusal plane-tooth axis angle, $X_2$: variation of ramus-occlusal plane angle). Conclusion : It was suspected that the reasons of root curvature were change of tooth axis caused by contact with 2nd deciduous tooth and amount of mesial and superior movement related to change of occlusal plane.

영상처리를 이용한 정자의 운동 특성 분석

심훈섭,이원진,박광석,백재승,Shim, Hoon-Sup,Yi, Won-Jin,Park, Kwang-Suk,Paick, Jae-Seung 대한전자공학회 1994 전자공학회논문지-B Vol.b31 No.11

본 논문에서는 영상처리 방법을 이용하여 정자의 운동 특성을 분석하는 자동화된 방법을 개발하였다. 시스템의 구성은 별도의 전용 프로세서를 사용하지 않고 PC와 간단한 영상처리 보드로 이루어진다. 영상 처리 보드는 영상을 받아들이는 데 사용되며 PC는 영상을 처리한 다음 분석해서 정자의 운동 특성을 나타내 주는 특성 변수의 값을 계산한다. 분석 알고리듬으로서 중요한 것은 정자의 위치 검출 알고리듬과 정자의 운동 경로를 추적하는 Match matrix 방법이다. 분석한 결과를 수작업 방법 그리고 전용 프로세서를 이용하는 방법과 비교하여 신뢰할 만한 결과를 얻었다. In this paper, we developed an analyzing method of the motional characteristics of sperm, using image processing technology. Without the aid of a dedicated image-processor, this processing of a personal computer(PC) and a simple image processing board. The image processing board is used for acquiring images from a microscopic imaging source. The PC processes the images from the board and computes the parameters of motional characteristics of sperms. The algorithm of the site detection of sperms and the 'Match Matrix Method' is noteworthy. After comparing the results of our method with those of the manual method, and with those of the method using a dedicated image-processor, we concluded that our method is useful and reliable.

디지털 방사선영상 시스템의 기본적 원리

최진우,이원진,Choi, Jin-Woo,Yi, Won-Jin 대한영상치의학회 2010 Imaging Science in Dentistry Vol.40 No.4

Digital radiographic systems allow the implementation of a fully digital picture archiving and communication system (PACS), and provide the greater dynamic range of digital detectors with possible reduction of X-ray exposure to the patient. This article reviewed the basic physical principles of digital radiographic imaging system in dental clinics generally. Digital radiography can be divided into computed radiography (CR) and direct radiography (DR). CR systems acquire digital images using phosphor storage plates (PSP) with a separate image readout process. On the other hand, DR systems convert X-rays into electrical charges by means of a direct readout process. DR systems can be further divided into direct and indirect conversion systems depending on the type of X-ray conversion. While a direct conversion requires a photoconductor that converts X-ray photons into electrical charges directly, in an indirect conversion, lightsensitive sensors such as CCD or a flat-panel detector convert visible light, proportional to the incident X-ray energy by a scintillator, into electrical charges. Indirect conversion sensors using CCD or CMOS without lens-coupling are used in intraoral radiography. CR system using PSP is mainly used in extraoral radiographic system and a linear array CCD or CR sensors, in panoramic system. Currently, the digital radiographic system is an important subject in the dental field. Most studies reported that no significant difference in diagnostic performance was found between the digital and conventional systems. To accept advances in technology and utilize benefits provided by the systems, the continuous feedback between doctors and manufacturers is essential.

턱교정수술에서 3D simulation과 CAD/CAM의 활용

진임건(ImGeun Jin),양훈주(HoonJoo Yang),김대승(DeaSeung Kim),이원진(Won Jin Yi),황순정(Soon Jung Hwang) 대한치과의사협회 2012 대한치과의사협회지 Vol.50 No.11

We describes the process of 3D virtual treatment planning and of CAD/CAM for surgical splint in orthognathic surgery. The potential benefits and disadvantages of 3D virtual approach and the use of CAD/CAM system for the treatment of the patient with a maxillofacial deformity are discussed. For the more convenient applications,3D software should be improved.

3차원 광학 스캐너와 콘빔CT에서 생성된 디지털 모형의 비교

권혁진(Hyuk-Jin Kwon),김각균(Kack-Kyun Kim),이원진(Won-Jin Yi) 대한턱관절교합학회 2016 구강회복응용과학지 Vol.32 No.1

구강검진의 효과 증진을 위한 파노라마방사선사진의 필요성에 관한 연구

신민정,최보람,허경회,이원진,허민석,이삼선,최순철,Shin, Min-Jung,Choi, Bo-Ram,Huh, Kyung-Hoe,Yi, Won-Jin,Heo, Min-Suk,Lee, Sam-Sun,Choi, Soon-Chul 대한영상치의학회 2010 Imaging Science in Dentistry Vol.40 No.1

Purpose : This study was designed to evaluate the efficacy and utility of panoramic radiograph for the improvement of the periodic oral examinations. Materials and Methods : Clinical examinations and panoramic examinations were done for the 242 subjects of oral examinations. The results of panoramic radiograph interpretation were compared with the clinical findings. Two questionnaires were created. One was carried out before the panoramic examination and the other done afterwards, to find out the subjects' cognition and satisfaction for the clinical and panoramic examinations. Results : 1. Panoramic findings showed a higher detection rate of 31.9% for periodontal diseases, and 23.1% for dental caries than clinical findings. 2. The additional abnormalities detected through panoramic examinations were impacted tooth in 81 subjects (33.6%), maxillary sinus abnormalities in 28 subjects (11.6%), condylar abnormalities in 5 subjects (2.1%), congenital and acquired dental anormalies in 59 subjects (24.5%), and other miscellaneous abnormalities in 34 subjects (14.1%). 3. 164 subjects (67.8%) were satisfied with the current periodic oral examination, and 75 subjects (31.1%) hoped for better accuracy. 4. In the first and second questionnaire, 154 subjects (67.0%) and 163 subjects (70.6%) responded respectively that panoramic examination was necessary, and 193 subjects (83.2%) responded that it actually helped. Conclusion : The panoramic examination was revealed to improve the effectiveness of the periodic oral examination and to increase the satisfaction of the subjects of examination.

방사선학적 골 소실량과 치주염 진행 단계의 딥러닝 기반 컴퓨터 보조 진단 방법: 다중기기 연구

이상정(Sang-Jeong Lee),이원진(Won-Jin Yi) 대한전기학회 2021 대한전기학회 학술대회 논문집 Vol.2021 No.7

건국의대 제 1회 기초의학 종합시험의 결과 분석

장성훈(Soung Hoon Chang),이원진(Won Jin Lee),이건세(Kun Sei Lee),이법이(Beob Yi Lee),고기석(Ki Seok Koh) 한국의학교육학회 1998 Korean journal of medical education Vol.10 No.1

To provide the information about overall test reliability and test improvement, we analyzed the first fundamental medical sciences examination at the Kon-Kuk University College of Medicine on August 23, 1997. The results are as follows: 1. The number of the items in the test is 230. The range of the scores is from 32.5 to 61.3(average percentage score: 50.0+/-6.1). Among the 39 students, three(7.7%) passed the examination with percentage scores of higher than 60. 2. The correlation coefficients between the fundamental medical sciences examination and academic records are 0.4682(the first semester in 1st grade), 0.5933(the second semester in 1st grade), and 0.6538(the first semester of 2nd grade), respectively. 3. Among the 230 items, 47(20.4%) are too difficult or too easy. Therefore these items are recommended to be discarded. 4. Among the 230 items, 115(50%) have lower discriminative indices(lower than 0.14) and 55(23.9%) have higher discriminative indices(higher than 0.23). 5. Among the 230 items, overall acceptable items are 101; the range of difficulty is 0.15~0.84 and discriminative indices are higher than 0.15. Good acceptance is shows in pharmacology and microbiology. 1997년 8월 23일에 건국대학교 의과대학 의학과 2학년 학생 39명 전원이 참석한 가운데 제1회 기초 의학 종합시험을 시행하였다. 본 연구의 목적은 처음 시행하는 기초의학 종합시험 결과에 대한 철저한 분석을 통해 문제점을 도출하여 보다 개선된 문제 출제를 유도하기 위함이다. 1.기초의학 종합시험은 총 230문제를 치렀으며, 100점 만점으로 환산한 성적은 최고 61.3점, 최저 35.2점이었으며, 평균은50.0+/-6.1이었다. 정답을 60%이상 맞추어 합격한 자는 39면 중 3명(7.7%)뿐이었다. 2. 이 시험성적과 의학과 1학년 1학기 평점과의 상관계수는 0.4682, 1학년 2학기 평점과는 0.5935, 1학년 전체 평점과는 0.5528, 2학년 1학기 평점과는 0.6538로 의학과 1,2학년 평점과 이 시험과는 일관되게 비교적 좋은 상관관계를 보였으며 특히 2학년 1학기 평점과 가장 좋은 상관을 보였다. 3. 총 230개 문항 중 난이도에서는 18개(7.8%)문항은 너무 쉬웠으며, 29개(12.6%)문항이 너무 어려웠다. 따라서 총 47개(20.4%)문항이 너무 쉽거나 어려워서 폐기해야 할 문항이었다. 4. 음성 변별도를 나타낸 문항이 35개(15.2%)이었으며 변별계수가 0.14이하의 불량한 문항은 115개(50%)이었다. 변별계수가 0.23이상의 양호한 문항은 55개(23.9%)이었다. 5. 난이도(0.15~0.84)와 변별도(0.15이상)모두가 수용할 만한 문항은 총 101개(43.9%)이었다. 10개 교과목 중 문제 수용률이 가장 높은 과목은 약리학(72%), 미생물학(68%)의 순서이었으며, 면역학과 행동과학의 수용률은 각각 0%이었다.