• 천문학회보
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• 제44권2호
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• pp.53.3-53.3
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• 2019

Recent work by Ravanbakhsh et al. (2017), Mathuriya et al. (2018) showed that convolutional neural networks (CNN) can be trained to predict cosmological parameters from the visual shape of the large scale structure, i.e. the filaments, clusters and voids of the cosmic density field. These preliminary works used the dark matter density field at redshift zero. We build upon these works by considering realistic mock galaxy catalogues that mimic true observations. We construct light-cones that span the redshift range appropriate for current and near future cosmological surveys such as LSST, EUCLID, WFIRST etc. In summary, we propose a novel multi-image input CNN to track the evolution in the morphology of large scale structures over cosmic time to constrain cosmology and the expansion history of the Universe.

• 한국의학물리학회:학술대회논문집
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• 한국의학물리학회 2002년도 Proceedings
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• pp.28-31
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• 2002

Filmless full-PACS in korea has rapidly been growing, since government had supported collaborative PACS project between industry and university hospital in late of 1995. At the same time, a small company had started PACS business, while the Korea PACS society was being formed. In the beginning, PACS societies had focused on developing peripheral solutions such as DICOM gateway for image acquisition, x-ray film digitizer, and viewing software for research or management of personal image data, while Samsung Medical Center had started installing an imported partial PACS system which had recently upgraded with a new system. In similar time frame, a few hospitals had started developing and installing domestic large scale full-PACS system. Several years later, many hospitals have installed full-PACS system with national policy of reimbursement for PACS exams in November 1999. It is believed that Korea is the first country that adopted PACS reimbursement for filmless full-PACS as a national policy. Both experiences of full-PACS installation and national policy generated tremendous intellectual and technological expertise about PACS at all levels, clinical, hospital management, education, and industrial sectors. There are currently three types of PACS system which includes domestic, imported, and hybrid PACS system with imported solution for core system and domestic solution for peripheral system. There are more than 20 domestic PACS companies and they have now enough experiences so that they are capable of installing a truly full-PACS system for large-scale teaching hospitals. PACS societies in Korea understand how to design, implement, install, manage, sustain, and provide good services for large-scale full-PACS. PACS society has also strength for the highest integration technology of the Hospital Information. However, further understanding and timely implementation of continuously evolving international standard and integrated healthcare enterprise concepts may be necessary for international leading of PACS technologies for the future.

• 대한한의진단학회지
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• 제17권3호
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• pp.233-240
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• 2013

Objectives The objective and universal grading system for the facial nerve palsy is needed to the objectification of treatment in Oriental medicine. In this study, the facial nerve palsy grading was developed with combination of image processing technique and Nottingham scale. Methods The developed system is composed of measurement part, image processing part, facial nerve palsy evaluation part, and display part. With the video data recorded by webcam at measurement part, the positions of marker were measured at image processing part. In evaluation part, Nottingham scales were calculated in four different facial expressions with measured marker position. The video of facial movement, time history of marker position, and Nottingham scale were displayed in display part. Results & Conclusion The developed system was applied to a normal subject and a abnormal subject with facial nerve palsy. The left-right difference of Nottingham scores was large in the abnormal compared with the normal. In normal case, the change of the length between supraorbital point and infraorbital point was larger than that of the length between lateral canthus and angle of mouth. The abnormal case showed an opposite result. The developed system showed the possibilities of the objective and universal grading system for the facial nerve palsy.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2005년도 학술발표회(1)
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• pp.101-102
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• 2005

• Journal of Information Processing Systems
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• 제18권1호
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• pp.48-58
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• 2022

Blind restoration for motion-blurred images is always the research hotspot, and the key for the blind restoration is the accurate blur kernel (BK) estimation. Therefore, to achieve high-quality blind image restoration, this thesis presents a novel windowed-total-variation method. The proposed method is based on the spatial scale of edges but not amplitude, and the proposed method thus can extract useful image edges for accurate BK estimation, and then recover high-quality clear images. A large number of experiments prove the superiority.

• 한국측량학회지
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• 제20권3호
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• pp.313-321
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• 2002

고해상도 위성영상의 공급이 현실화됨에 따라 위성영상을 기반으로 한 수치지형도나 주제도의 신규제작 및 갱신에 많은 관심이 모이고 있다. 본 연구는 아이코노스 위성영상을 이용하여 기존의 축척 l/5,000 및 l/25,000수치지도의 수정 및 갱신 가능성을 제시하고자 하였다. 아이코노스 단영상에서 기존 수치지도상의 기준점을 활용하여 기하보정을 수행하였으며, 기존 수치지도의 3차원 등고선자료와 표고성과에 의해 수치표고모형을 추출하여 정사영상을 생성하였다. 정사보정된 위성영상과 기존 수치지도를 중첩하여 변화된 지형지물들을 스크린 디지타이징 방법으로 수정하였고, 위치정확도 분석을 위해 변하지 않은 지역의 지형지물들을 위성영상위에 직접 작도하여 비교하였다. 그 결과, 평면위치오차를 $\pm$3.35m의 평균제곱근오차로 산출할 수 있었으므로 축척 1/10,000 이하의 수치지도 갱신에는 충분히 그 활용이 가능한 것으로 판단되며, 입체영상을 사용하고 지상기준점 측량을 병행한 갱신방법을 사용한다면 축척 l/5,000이상의 대축척 수치지도 갱신도 가능할 것이다.

• 한국측량학회:학술대회논문집
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• 한국측량학회 2003년도 춘계학술발표회 논문집
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• pp.321-326
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• 2003

The subjects of this study are to examine and to apply the methods of making 1:5,000 scale maps using 1m resolution stereo images of IKONOS for the Munsan area of Paju-city where aerial photo surveying cannot possible because of security conditions. GCP(Ground Control Point) were acquired from GPS surveying and were to perform geometric corrections on images. Digital Map used IKONOS stereo images and it worked from the digital analytical stereoplotter. From field investigation, RMSE errors of the plane and vertical positions are estimated to 1.706m and 1.231m, respectively. The plane accuracy is better than an accuracy required by NGIS (national GIS) programs. Local information from field investigation was added and the resulting maps should be good as digital map under the scale of 1/5,000.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제16권7호
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• pp.2359-2376
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• 2022

With the exponential growth of medical image big data represented by high-resolution CT images(CTI), the high-resolution CTI data is of great importance for clinical research and diagnosis. The paper takes lung CTI as an example to study. Retrieving answer CTIs similar to the input one from the large-scale lung CTI database can effectively assist physicians to diagnose. Compared with the conventional content-based image retrieval(CBIR) methods, the CBIR for lung CTIs demands higher retrieval accuracy in both the contour shape and the internal details of the organ. In traditional supervised deep learning networks, the learning of the network relies on the labeling of CTIs which is a very time-consuming task. To address this issue, the paper proposes a Weakly Supervised Similarity Evaluation Network (WSSENet) for efficiently support similarity analysis of lung CTIs. We conducted extensive experiments to verify the effectiveness of the WSSENet based on which the CBIR is performed.

• 한국정보처리학회:학술대회논문집
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• 한국정보처리학회 2010년도 춘계학술발표대회
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• pp.405-408
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• 2010

This paper presents a new feature extraction technique, correlation coefficient and Manhattan distance (MD) based method for recognition of rotated object in an image. This paper also represented a new concept of intensity invariant. We extracted global features of an image and converts a large size image into a one-dimensional vector called circular feature vector's (CFVs). An especial advantage of the proposed technique is that the extracted features are same even if original image is rotated with rotation angles 1 to 360 or rotated. The proposed technique is based on fuzzy sets and finally we have recognized the object by using histogram matching, correlation coefficient and manhattan distance of the objects. The proposed approach is very easy in implementation and it has implemented in Matlab7 on Windows XP. The experimental results have demonstrated that the proposed approach performs successfully on a variety of small as well as large scale rotated images.

• 유통과학연구
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• 제10권6호
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• pp.17-26
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• 2012

도농 복합형태인 인구 30만인 순천시에 종합슈퍼와 백화점 등 대규모점포 4개가 운영 중인 것은 대규모점포의 과잉공급이라는 지적이 제기되어 왔다. 그러나 순천시는 전남 동부권의 교통요지로서 광양시, 여수시, 보성군 및 구례군 등 인근 지역에서 1 시간 이내에 점포방문이 가능하다. 4개 점포는 도시와 농촌 지역의 거주자도 고객층으로 간주하여 차별화된 점포이미지 구축 전략을 수립하고 있다. 본 연구에서는 점포이미지 변수를 13개로 세분하여 각 점포의 이미지를 비교하였다. 점포이미지는 진열 상품의 다양성 및 품질, 점포 접근성, 매장 분위기 등 다양한 형태로 나타난다. 이러한 이미지는 고객들의 주관적 판단에 따라 각자에게 인지되고, 점포를 선택하는 주요 요인이 된다. 본 연구에서는 점포이미지 변수를 대분류 5개 소분류 13개로 분류하였다. SPSS Ver. 19를 이용한 요인분석에서는 5개로 대분류된 점포이미지가 3개의 요인으로 구분되어 추출되었다. 5개 대분류에서 편의성, 분위기 및 서비스 이미지로 분류된 이미지들이 첫 번째 공통요인으로 추출되었고 이를 본 연구에서는 부대서비스 요인으로 구분하여 기술하였다. 5개 분류에서 편의성 이미지로 분류되었던 접근성과 상품관련 이미지로 분류되었던 상품다양성과 가격 이미지는 같은 공통요인으로 추출되었다. 이는 점포가 위치하고 있는 지역이 대도시인가 또는 지방 중소도시인가, 설문 조사에 응한 집단의 특성에 따라 달라질 것으로 예상된다. 13개 이미지 변수에 대해서 점포간 및 응답자간 점포이미지 비교에서는 접근성, 가격, 브랜드 이미지 및 조명/음향 이미지에서 점포별 및 응답자 집단별로 차이가 있는 것으로 나타났다. 본 연구는 두 가지 측면에서 한계를 가지고 있다. 첫째, 도농복합형태의 지방 중소도시 거주자만을 대상으로 조사하였다. 점포가 소재하고 있는 지역의 교통체증 정도, 응답자 집단의 생활수준 등에 따라 고객이 느끼는 점포이미지는 차이를 보일 수 있기 때문이다. 둘째, 대규모점포를 이용하는 고객만을 대상으로 하였다. 지방 도시에는 비교적 규모가 큰 전통시장이 열리고 있으며, 대규모점포와 전통시장은 상품의 종류, 가격 등에서 경쟁을 하고 있다. 대규모점포를 이용하는 고객과 전통시장을 방문하는 고객이 느끼는 점포이미지는 다를 수 있다. 추후 연구에서는 대도시 소재 점포와 지방 중소도시 소재 점포와의 동시 조사로 점포이미지에 대한 상대적 비교가 필요할 것이다. 또한 동일 지역에서 대규모점포 이용 고객과 준대규모점포 또는 전통시장 이용 고객층에 대한 상대적 비교 연구도 이루어져야 할 것으로 사료된다.