Mean Shift Segmentation을 이용한 스마트폰 기반의 수채화 효과 변환 기법

이상걸,김철기,차의영,Lee, Sang-Geol,Kim, Cheol-Ki,Cha, Eui-Young 한국정보통신학회 2010 한국정보통신학회논문지 Vol.14 No.11

본 논문에서는 최근 급속히 보급되고 있는 스마트폰에서 촬영한 사진 영상을 수채화 효과가 나도록 변환하는 기법에 대하여 제안한다. 제안하는 수채화 효과 변환 기법은 영상처리 분야에서 많이 사용하는 양방향 필터링(bilateral filtering)과 평균 이동 분할(mean shift segmentation)을 이용한다. 먼저 입력 영상을 스마트폰 화면 해상도로 크기 변환한 후 양방향 필터링을 이용하여 사진의 외곽선 부분은 보존하면서 고주파 성분을 약화시키도록 한다. 다음으로 양방향 필터링을 거친 영상에서 평균 이동분할을 수행하여 최종영상을 생성한다. 실험을 통하여 스마트폰의 연산속도를 고려한 평균 이동 분할의 파라미터 값을 설정하여 다양한 사진에 대하여 수채화 효과가 잘 나타나는 것을 확인하였다. We propose a retouching method that converts a photography taken by smartphone to a watercolor painting image using bilateral filtering and mean shift segmentation which are mostly used in image processing. The first step is to convert an input image to fit the screen resolution of smartphone. And next step is to weaken high frequency components of the image, while preserving the edge of image using the bilateral filtering. And after that we perform mean shift segmentation from the bilateral filtered image. We apply parameters of mean shift segmentation considering the processing speed of smartphone. Experimental result shows that our method can be applied to various types of image and bring better result.

골반내 후복막강의 obturator fossa에서 발생한 양성 신경초종

이상걸(Sang Geol Lee),이은혜(Eun Hye Lee),심정연(Jeong Yun Shim),이찬(Chan Lee),신명철(Myung Choel Shin),이위현(Wee Hyun Lee) 대한산부인과학회 2000 Obstetrics & Gynecology Science Vol.43 No.2

The schwannoma is a benign neoplasm originating from Schwann cell. Solitary nerve sheath tumors such as benign schwannomas arising in the pelvic retroperitoneum are infrequently reported. Those tumors can indeed be misdiagnosed for other more common conditions both clinically and instrumentally. We report a very rare case of a benign retroperitoneal pelvic schwannoma of the obturator fossa, which was incidentally found and misdiagnosed as adnexal mass preoperatively in fifty one-years-old postmenopausal women.

Mean Shift Segmentation을 이용한 수채화 스타일 변환 기법

이상걸(Sang-Geol Lee),김철기(Cheol-Ki Kim),차의영(Eui-Young Cha) 한국컴퓨터정보학회 2010 한국컴퓨터정보학회 학술발표논문집 Vol.18 No.2

본 논문에서는 영상처리에서 많이 사용하는 bilateral filtering과 mean shift segmentation을 이용하여 일반적인 사진을 수채화 스타일로 변환하는 기법에 대하여 제안한다. 먼저 bilateral filtering을 이용하여 사진의 외곽선 부분은 보존하면서 고주파 성분을 약화시키도록 한다. 그리고 bilateral filtering된 영상에서 mean shift segmentation을 수행하여 수채화 스타일의 영상을 생성한다. 본 논문에서 제안하는 기법으로 다양한 사진에 대하여 실험한 결과 수채화 스타일로 잘 변화되는 것을 확인하였으며 특히 주광에서 촬영한 풍경 사진들에 대하여 보다 우수한 성능을 보임을 확인하였다.

일 노인요양시설 치매 환자의 사망률과 예측인자

이상걸(Sang Keol Lee),김대희(Dae Hee Kim),서국희(Guk-Hee Suh) 대한노인정신의학회 2009 노인정신의학 Vol.13 No.1

Objectives : To investigate mortality rates and predictors of mortality in dementia patients (prevalence cohort) resident at institution. Methods : We followed up a dementia cohort for 5 years. A total of 273 subjects with dementia were longitudinally assessed at baseline, 6 months and 12 months and then checked whether alive or dead every 1 year for 5 years. Their mortality was compared with sociodemographic and clinical variables using Cochran-Mantel-Haenszel test and independent sample t-test. Survival time quartiles were used to describe the time until when 25%, 50%, and 75% of patients died. Kaplan Meier log-rank tests were used for testing the equality of survival among groups when identifying some disruptive agitated behaviors as mortality predictors. Relative risk (RR) with 95% confidence intervals were calculated by the Cox regression analysis. Results : In this study, overall 5-year mortality rate was 63.0% (12.6% per year). Median survival after baseline evaluation was 2.85 years, whereas median survival after institutionalization was 6.42 years. Log-rank tests revealed that some disruptive behaviors (i.e., Cagras syndrome, screaming, trying to get to a different place, intentional falling) were significantly higher in the deceased group. Mortality in subjects with dementia depended on old age {over 85, relative risk (RR) : 1.04;95% confidence interval (CI) : 1.02-1.06}, male gender (RR : 2.04;CI : 1.28-3.25), lower MMSE-K score (RR : 1.03;CI : 1.00-1.06). Conclusion : We expect that this study may provide basic health information for health policy making in institutional care approaches in Korea.

Mean Shift Segmentation을 이용한 수채화 효과 생성 기법

이상걸(Sang-Geol Lee),김철기(Cheol-Ki Kim),차의영(Eui-Young Cha) 한국컴퓨터정보학회 2010 韓國컴퓨터情報學會論文誌 Vol.15 No.9

본 논문에서는 영상처리에서 많이 사용하는 양방향 필터링(bilateral filtering)과 평균 이동 분할(mean shift segmentation)을 이용하여 일반적인 사진을 수채화 효과가 나도록 하는 리터칭 기법에 대하여 제안한다. 먼저 양방향 필터링을 이용하여 사진의 외곽선 부분은 보존하면서 고주파 성분을 약화시키도록 한다. 그리고 양방향 필터링된 영상에서 각각 DoG(Difference of Gradient) 에지 추출과 평균 이동 분할을 수행한다. 이때 DoG 에지 추출은 원영상의 RGB 색상 공간을 CIELAB 공간으로 변환 후 휘도(luminance) 성분만 이용하여 추출하도록 하며 두 결과를 결합하여 최종 영상을 생성한다. 본 논문에서 제안하는 기법으로 다양한 사진에 대하여 실험한 결과 수채화 효과가 잘 나타나는 것을 확인하였으며 특히 주광에서 촬영한 풍경 사진들에 대하여 보다 우수한 성능을 보임을 확인하였다. We propose a retouching method that converts a general photography to a watercolor painting image using bilateral filtering and mean shift segmentation which are mostly used in image processing. The first step is to weaken high frequency components of the image, while preserving the edge of image using the bilateral filtering. And after that we perform DoG(Difference of Gradient) edge extraction and mean shift segmentation respectively from the bilateral filtered image. The DoG edge extraction is performed using luminance component of the image whose RGB color space is transformed into CIELAB space. Experimental result shows that our method can be applied to various types of image and bring better result, especially against the photo taken in daylight.

다중 카메라를 이용한 3차원 개체 추적 시스템

이상걸 ( Sang-geol Lee ),구경모 ( Kyung-mo Koo ),서영욱 ( Young-wook Seo ),차의영 ( Eui-young Cha ) 한국정보처리학회 2004 한국정보처리학회 학술대회논문집 Vol.11 No.1

본 시스템은 어항속에 있는 물고기 움직임을 추적하기 위해 두 대의 카메라로부터 동시에 독립된 영상을 획득하고 획득된 영상을 처리하여 좌표를 얻어내고 3차원 좌표로 생성해내는 시스템이다. 제안하는 방법은 크게 두 대의 카메라로부터 동시에 영상을 획득하는 방법과 획득된 영상에 대한 처리 및 물체 위치 검출, 그리고 3차원 좌표 생성으로 구성된다. Frame grabber를 사용하여 두 개의 카메라로부터 동시에 영상을 획득하며, 3개의 연속된 프레임에 대한 차영상과 ART2(Adaptive Resonance Theory)를 이용하여 각각의 영상에서의 물고기 위치를 검출한다. 검출된 각각의 좌표를 병합하여 3차원 좌표를 생성하며, 추적 결과는 OpenGL을 이용하여 3차원으로 재생한다.

마코프-연쇄 모형을 이용한 광역도시권 설정 및 권역 변화 분석에 관한 연구

이상걸(Lee, Sang Geol),우명제(Woo, Myungje) 대한국토·도시계획학회 2016 國土計劃 Vol.51 No.7

체외수정시술을 받은 산모와 자연 임신된 산모에서의 임신 중반기 산모혈청 삼중식별검사결과 비교에 관한 연구

이상걸(Sang Geol Lee),신승주(Seung Joo Shin) 대한산부인과학회 1999 Obstetrics & Gynecology Science Vol.42 No.8

목적: 체외수정시술을 받은 산모와 자연 임신된 산모와의 Down 증후군 및 개방성 신경관 결손증에 대한 산모 혈청 검사상의 선별 양성율에 차이가 있는지를 알아보아서 IVF 태아에서도 triple test가 잘 적용되는지를 연구하였다. 연구방법: 1995년 1월부터 1998년 4월까지 각각 200 명씩의 단태아 임신 산모를 대상으로 하여 임신 15주에서 20주사이에 산모 혈청 삼중식별검사를 시행하였다. 결과: 인공수정시술 군에서 선별 양성율은 0.5%이고 자연 임신군 에서는 1%이었다. AFP, unconjugated-E3, hCG의 평균치는 인공수정시술 군에서 각각 0.92 MoM, 1.44 MoM, 0.87 MoM 이었고 자연임신 군에서 각각 0.86 MoM, 1.28 MoM, 0.83 MoM 이었다. 통계학적 분석은 student t-test, chi-square test 등을 이용하였으며 P-value 〈0.05 인 경우 통계학적 유의성이 있는 것으로 분석하였다. 결론: 본 연구결과 두 집단간의 Down 증후군에 대한 산모 혈청선별검사상 양성일 확률에는 차이가 없는 것으로 밝혀졌고 향후 많은 환자 분석을 하여 좀더 정확한 비교치를 구할 필요가 있고 앞으로 인공수정시술을 받은 산모의 혈청선별검사에 도움이 되면 한다. Objective : To evaluate the results of second-trimester maternal serum triple-marker screening test for Down syndrome and open neural tube defects in singleton pregnancies conceived from in vitro fertilization, the screen positive rates and triple-marker level of patients conceiving singleton pregnancies by IVF were compared to those of pregnancies conceived naturally. Methods : Two hundred singleton pregnancies conceived by IVF and naturally conceived pregnancies who had done maternal serum screening test during the second trimester were analyzed from January 1995 to April 1998. Results : One (0.5%) of the 200 cases of IVF singleton pregnancies had a positive result for Down syndrome compared with 1% of screen positive rate in the 200 cases of naturally conceived pregnancies. The median level of the triple markers were 0.92 multiples of the median(MoM) for alpha-fetoprotein(AFP), 1.44 MoM for unconjugated estriol(E3) and 0.87 MoM for human chorionic gonadotropin(hCG) respectively. Conclusion : The positive rate of triple test for Down syndrome and open neural tube defect in the two groups were significantly not different. As additional data are collected, corrected standards should be determined.

재일코리안 차세대의 정체성과 통일의식 상관성 연구

이상걸(Lee, Sang-Kul),임채완(Lim, Chae-Wan) 동북아시아문화학회 2016 동북아 문화연구 Vol.1 No.46

This study examines unification consciousness of New Generation in Koreans in Japan and how national identity of them has changed. Especially it classifies types of the identity and analyzes correlation between the types and unification consciousness. At first this study examines existing researches and establishes typology of the identity of New Generation in Koreans in Japan. It reviews existing typology critically and transforms it creatively in accordance with characteristics of the object of this study. The typology consists of four types on the basis of ethnicity and citizenship; combination-oriented, ethnic-oriented, citizen-oriented and individual-oriented. Not only by referring to the existing researches but by adjusting it for the purpose of this study, it sets four subordinate components including unification willingness, concern degree of unification, practical attitude and ways of unification preference. In the view of study results, it is possible to draw several conclusions. First of all, to inspire the unification consciousness the ethnic-identity should be established because there is a correlation between the unification consciousness of New Generation in Koreans in Japan and the ethnic identity standard as it is marked on the results in a depth interview. Second, if the unification consciousness and the ethnic identity were low, the reason of it can be from the absence of the unification education. For growth of New Generation as a main agent of the unification, the organized unification education is needed. Thirdly, the unification education should be customized to New Generation by their identity types. Since each identity type has a difference in unification consciousness according to the results. This study is confirmed that the unification consciousness is affected on the standard of the ethnic identity by not only a theoretical investigation but also an actual investigation. Furthermore it is meaningful that it is confirmed by the depth interview of the experts. Also it is significant that the object of this study is New Generation at this point of time which the role of Korean residents is getting important as main agent of the unification. In addition, this study established the correlation between the identity and the unification consciousness, although the previous study is not enough. Also it ascertains the political implication that the establishment of the ethnic identity has to be preceded to arise the upright unification consciousness. Based on these outcomes, there are several suggestions for improvement of this study. First of all, object and method of study should be extended. The number of Choseon school is much more than that of Korean school. Also Choseon school accepts the curriculum of General Association of Korean Residents in Japan and North Korea. Therefore the comparison study between the students of ethnic school and Choseon school should be implemented. Also the comparison study between the students of ethnic school and Japan school also should be implemented. In addition to, the comparison study between New Generation of Koreans in China and U.S.A. is also needed. Second of all, based on the context of this study, the subject of this study is limited to the identity type, the unification consciousness and the correlation between them. The subject of study should be extended to an improvement plan of the unification education and the curriculum of unification education for stiffen the capability as main agent of the unification. Also the study about an actual condition and the way of vitalization of Korea community network should be implemented. Until now, the role of Korean residents abroad in the unification process is just an intermediary. However New Generation in Koreans in Japan, teachers, and experts agree that the role of Korean residents abroad is important in the process of unification. According to an extension of economical bases and an improv

다공성 소재를 사용한 운반용 공기 부상시스템 개발에 관한 연구

이상걸(Sang-Geol Lee),정동택(Dong-Teak Chung),정경석(Kyung-Seok Jeong),김태연(Tae-Yeon Kim) 대한기계학회 2017 대한기계학회 춘추학술대회 Vol.2017 No.11

When using a conveyor for the movement of a surface-treated object, there is a high possibility that the surface of the object is damaged by friction with the surface of the conveyor. In order to prevent such surface damage, it is an alternative to use a method of making the object slip by using the pneumatic pressure. In order to float an object from the surface, a large number of air holes must be made on the surface so that the pneumatic pressure is evenly dispersed, and this processing causes an increase in the production cost. In this study, we have carried out a study to apply the air floating system which moves by floating the object using the low cost porous material as a substitute method, and it confirms the validity of the method of transporting without damaging the surface of the object.