SMD의 위치 및 불량 검색을 위한 수리형태학의 적용 ( Application of Mathematical Morphology for SMT )

권준식,우상찬,최종수 대한전자공학회 1993 대한전자공학회 워크샵 Vol.1993 No.-

형태학적 골격에서의 거리 변환을 이용한 2차원 물체 인식

권준식,최종수 대한전자공학회 1996 전자공학회논문지-B Vol.b33 No.7

In this paper, w epropose a new mehtod to represent the shape and to recognize the object. The shape description and the matching is implemented by using the distance transform on the morphological skeleton. The employed distance transform is the chamfer (3,4) distance transform, because the chamfer distance transform (CDT) has an approximate value to the euclidean distance. The 2-D object can be represented by means of the distribution of the distance transform on the morphological skeleton, the number of skeletons, the sum of the CDT, and the other features are employed as the mtching parameters. The matching method has the invariant features (rotation, translation, and scaling), and then the method is used effectively for recognizing the differently-posed objects and/or marks of the different shape and size.

이동전화 단말기 판매보조금 실태조사 연구

권준식 世明大學校 1998 世明論叢 Vol.7 No.-

In this paper, to propose the healthy policy for the good mobild communication service. I researched an actual state of the mobile telephone sale subsidy and subscribers of cellular and PCS companies. I investigated the present conditions of mobile communicaion service and the point at issue, and propose the desirable strategies such as the improvement of call quality through a network construction and added service expansion and the healthy strategy such as the removal of obligaiton subscription term and the reduction of call fee.

SMD의 위치 및 불량 검색을 위한 수리형태학의 적용 ( Application of Mathematical Morphology for SMT )

권준식,우상찬,최종수 한국통신학회 1993 한국통신학회 워크샵 Vol.- No.-

SMD의 위치와 방향 계산 및 검사 알고리듬 : 형태학적 방법과 Hough 변환 방법의 비교

권준식,최종수 대한전자공학회 1995 전자공학회논문지-B Vol.b32 No.1

New morphological positioning algorithm and inspection method are presented and compared with a method by means of the Hough transform. The positioning algorithm is the process of finding the center and the rotated angle of the surface mounted device (SMD). The inspection method is capable of detecting the location of broken or bent leads. In order to obtain the center and the orientation of the SMD rapidly, the Hough transform method utilizes feature points (concave points) and is executed on a DSP board. The proposed morphological method is implemented by using the morphological skeleton subsets, and an ultimate orientation is decided by the Hit-or-Miss transform (HMT). In the inspection process, two inspection methods also are presented. The first method utilizes the morphological methods, i.e., opening and closing. It is performed before the positioning process and called an initial inspection. The second method follows the positioning process and is performed by an inspection of intersections of rulers and the lead edge (or the skeleton). It is a ruling technique which is referred to as a detailed inspection. We find the morphological approach is preciser and faster than the Hough approach by the comparison of the proposed algorithms.

지문영상 처리를 위한 개선된 병렬 세선화 알고리즘

권준식 대한전자공학회 2004 電子工學會論文誌-SP (Signal processing) Vol.43 No.1

지문영상에서 신뢰할 만한 특징을 추출하기 위한 세선화 알고리즘은 전처리 과정에 있어서 매우 중요한 부분을 차지한다. 본 논문에서 제안하는 세선화 알고리즘은 2치화된 지문영상의 연결성을 파괴하지 않고, 중심선에 가장 관접한 골격선을 최소 1화소 두께로 만들 수 있는 강건한 병렬 세선화 알고리즘을 제안하는 것이다. 제안한 기법은 3개의 부반복에 의해 반복 수행되며, 첫 번째 부반복은 내부점에 의해 최외각 경계 화소만을 제거하는 것이며, 두 번째 부반복은 2화소 두께의 골격선을 찾아 한쪽 골격선만을 추출한다. 세 번째 부반복은 골격선에 여분으로 존재하는 2화소 두께의 화소를 제거한다. 따라서 제안하는 세선화 방법은 회전과 잡음에 강건하며 균형 잡힌 중심선을 만들어낸다. 세선화 알고리즘의 성능을 평가하기 위하여 이전에 발표된 알고리즘들과 비교 분석하였다. To extract the creditable features in fingerprint image, many people use the thinning algorithm that has a very important position in the preprocessing. In this paper, we propose the robust parallel thinning algorithm that can preserve the connectivity of the binarized fingerprint image, make the thinnest skeleton with 1-pixel width and get near to the medial axis extremely. The proposed thinning method repeats three sub-iterations. The first sub-iteration takes off only the outer boundary pixel by using the interior points. To extract the one side skeletons, the second sub-iteration finds the skeletons with 2-pixel width. The third sub-iteration prunes the needless pixels with 2-pixel width existing in the obtained skeletons and then the proposed thinning algorithm has the robustness against the rotation and noise and can make the balanced medial axis. To evaluate the performance of the proposed thinning algorithm we compare with and analyze the previous algorithms.

적응형 임계값을 이용한 오차확산 방법

권준식,이재영,박유신 대한전자공학회 2006 電子工學會論文誌-SP (Signal processing) Vol.43 No.1

The error diffusion method is one of the digital halftoning processes that transforms the continuous-tone image to the binary image and the method has the excellent reproduction ability. However the error diffusion method using the permanent threshold has difficulty in proper binarization, so the method has the periodic pattern and is unpleasant to the eye. In this paper, to reduce defects and to binarize properly, we propose the error diffusion method using the adaptive threshold. Depending on the intensity distribution of the input gray scale image, we decided on the adaptive threshold with the average of the intensities. The error diffusion method with the adaptive threshold has the better performance than the existing method and is evaluated with experiments and comparisons. 오차확산 방법은 프린터 등에 적용하기 위해 연속계조의 영상을 흑과 백의 이진영상으로 표현하는 디지털 하프토닝의 방법 중 하나로 우수한 영상 재현 능력을 보인다. 그러나 기존의 오차확산 방법은 임계값을 고정적으로 가지면서 오차확산을 하기 때문에 입력 영상에 대해서 충실한 이진화 처리가 어렵고 눈에 거슬리는 주기적인 패턴이 발생하는 단점이 있다. 본 논문에서는 입력 영상의 충실한 이진화 처리 및 주기적인 패턴을 감소시키기 위해 적응형 임계값을 적용하여 오차 확산하는 방법을 제안하였다. 적응형 임계값은 입력 농담 영상의 밝기분포를 감안하여 평균치를 산출하는 방법을 사용하였다. 이진화 처리 방법에 대해서 고정임계값을 이용한 오차확산 방법과 제안한 방법을 비교 분석한 결과 제안하는 적응형 임계값을 사용한 오차확산 방법이 더 우수한 디지털 하프토닝 방법임을 실험과 비교를 통해 확인할 수 있었다.

Systematic Preventable Trauma Death Rate Survey to Establish the Region-based Inclusive Trauma System in a Representative Province of Korea

권준식,Jin-Hee Lee,황경진,Heo Yunjung,조항주,이국종,정경원 대한의학회 2020 Journal of Korean medical science Vol.35 No.50

Background: Trauma mortality review is the first step in assessing the quality of the trauma treatment system and provides an important basis for establishing a regional inclusive trauma system. This study aimed to obtain a reliable measure of the preventable trauma death rate in a single province in Korea. Methods: From January to December 2017, a total of 500 sample cases of trauma-related deaths from 64 hospitals in Gyeonggi Province were included. All cases were evaluated for preventability and opportunities for improvement using a multidisciplinary panel review approach. Results: Overall, 337 cases were included in the calculation for the preventable trauma death rate. The preventable trauma death rate was estimated at 17.0%. The odds ratio was 3.97 folds higher for those who arrived within “1–3 hours” than those who arrived within “1 hour.” When the final treatment institution was not a regional trauma center, the odds ratio was 2.39 folds higher than that of a regional trauma center. The most significant stage of preventable trauma death was the hospital stage, during which 86.7% of the cases occurred, of which only 10.3% occurred in the regional trauma center, whereas preventable trauma death was more of a problem at emergency medical institutions. Conclusion: The preventable trauma death rate was slightly lower in this study than in previous studies, although several problems were noted during inter-hospital transfer; in the hospital stage, more problems were noted at emergency medical care facilities than at regional trauma centers. Further, several opportunities for improvements were discovered regarding bleeding control.

지문영상 처리를 위한 개선된 병렬 세선화 알고리즘

권준식 대한전자공학회 2004 電子工學會論文誌-SP (Signal processing) Vol.41 No.03

To extract the creditable features in fingerprint image, many people use the thinning algorithm that has a very important position in the preprocessing. In this paper, we propose the robust parallel thinning algorithm that can preserve the connectivity of the binarized fingerprint image, make the thinnest skeleton with 1-pixel width and get near to the medial axis extremely. The proposed thinning method repeats three sub-iterations. The first sub-iteration takes off only the outer boundary pixel by using the interior points. To extract the one side skeletons, the second sub-iteration finds the skeletons with 2-pixel width. The third sub-iteration prunes the needless pixels with 2-pixel width existing in the obtained skeletons and then the proposed thinning algorithm has the robustness against the rotation and noise and can make the balanced medial axis. To evaluate the performance of the proposed thinning algorithm, we compare with and analyze the previous algorithms. 지문영상에서 신뢰할 만한 특징을 추출하기 위한 세선화 알고리즘은 전처리 과정에 있어서 매우 중요한 부분을 차지한다. 본 논문에서 제안하는 세선화 알고리즘은 2치화된 지문영상의 연결성을 파괴하지 않고, 중심선에 가장 근접한 골격선을 최소 1화소 두께로 만들 수 있는 강건한 병렬 세선화 알고리즘을 제안하는 것이다. 제안한 기법은 3개의 부반복에 의해 반복 수행되며, 첫 번째 부반복은 내부점에 의해 최외각 경계 화소만을 제거하는 것이며, 두 번째 부반복은 2화소 두께의 골격선을 찾아 한쪽 골격선만을 추출한다. 세 번째 부반복은 골격선에 여분으로 존재하는 2화소 두께의 화소를 제거한다. 따라서 제안하는 세선화 방법은 회전과 잡음에 강건하며 균형 잡힌 중심선을 만들어낸다. 세선화 알고리즘의 성능을 평가하기 위하여 이전에 발표된 알고리즘들과 비교 분석하였다.

형태학적 골격에서의 챔퍼 거리 변환을 이용한 2차원 물체인식 ( 2-D Object Recognition Using Chamfer Distance Transform on Morphological Skeleton )

권준식,최종수 대한전자공학회 1994 대한전자공학회 학술대회 Vol.1994 No.1