• Title/Summary/Keyword: closing operator

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Image Mosaics using Morphological Corner Detection (모폴로지 코너 검출법을 이용한 영상 모자이크)

  • 조세연;이정호;유형승;조아영;정동석
    • Proceedings of the Korean Information Science Society Conference
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    • 2004.04b
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    • pp.700-702
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    • 2004
  • 모자이크는 설러 장의 영상을 하나의 큰 영상으로 만드는 것을 말한다. 본 논문은 asymmetrical closing이라고 불리는 모폴로지에 의한 closing operator를 사용한 영상 모자이크에 관한 연구이다. asymmetrical closing을 하기 위한 structuring element를 소개하고 이것을 이용한 코너 정 추출 방법 및 local maxima에 대해서도 소개한다. 여러 개의 코너 정들 중 조건을 만족하는 tie point들을 이용하여 Perspective 변환 파라미터를 추출하여 최종 모자이크 결과 영상을 생성하게 된다.

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A Study on the Multiple Spurious Operation Analysis in Fire Events Probabilistic Safety Assessment of Domestic Nuclear Power Plant (국내 원자력발전소의 화재사건 확률론적안전성평가에서 다중오동작 분석 연구)

  • Kang, Dae Il;Jung, Yong Hun;Choi, Sun Yeong;Hwang, Mee-Jeong
    • Journal of the Korean Society of Safety
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    • v.33 no.6
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    • pp.136-143
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    • 2018
  • In this study, we conducted a pilot study on the multiple spurious operations (MSO) analysis in the fire probabilistic safety assessment (PSA) of domestic nuclear power plant (NPP) to identify the degree of influence of the operator actions used in the MSO mitigation strategies. The MSO scenario of the domestic reference NPP selected for this study is refueling water tank (RWT) drain down event. It could be caused by spurious operations of the containment spray system (CSS) of the reference NPP. The RWT drain down event can be stopped by the main control room (MCR) operator actions for stopping the operation of CSS pump or closing the CSS motor operated valve if the containment spray actuation signal (CSAS) is spuriously actuated. Outside the MCR, it can be stopped by operator actions for closing the CSS manual valves or motor operated valve or stopping the operation of CSS pump. The quantification result of a fire PSA model that takes into account all recovery actions for the RWT drain down event lead to risk reduction by about 95%, compared with quantification result of fire PSA model without considering them. Among the various operator actions, the recovery action for the spurious CSAS operations and the operator action for the manual valve are identified as the most important operator actions. This study quantitatively showed the extent to which the operator actions used as MSO countermeasures have affected the fire PSA quantification results. In addition, we can see the rank of importance among the operator recovery actions in quantitative terms.

Development of an Automatic Cap Opening And Closing Device for Unmanned Chemical Manufacturing Processes (화학제조공정의 무인화를 위한 자동 캡 개폐장치 개발)

  • Jun-Sik Lee;Oh-Seong Kwon;Jun-Ho Lee
    • Journal of the Korean Society of Industry Convergence
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    • v.27 no.1
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    • pp.71-76
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    • 2024
  • Automatic production systems are constantly advancing technologies to improve productivity and safety. Specifically, liquid filling machines are primarily utilized to package products into drums after manufacturing process in the hazardous chemical industry. Most existing filling machines allow the operator to open the drum cap and inject the product directly or semi-automation. In this study, we have developed a cap opening and closing mechanism onto the existing drum filling machine, enabling automatic and safe cap manipulation while filling the product in the IBC tank. By applying the appropriate torque value through numerical analysis, we confirmed that the system worked without any problems during the process of opening and closing the cap. Therefore, it is expected that the developed machine will give more production and reduce human efforts without risk in the chemical packaging industry.

Automatic Face Tracking based on Active Contour Model using Two-Level Composite Gradient Map (두 단계 합성 기울기 맵을 이용한 활성 외곽선 모델 기반 자동 얼굴 추적)

  • Kim, Soo-Kyung;Jang, Yo-Jin;Hong, Helen
    • Journal of KIISE:Software and Applications
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    • v.36 no.11
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    • pp.901-911
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    • 2009
  • In this paper, we propose a construction technique of two-level composite gradient map to automatically track a face with large movement in successive frames. Our method is composed of three main steps. First, the gradient maps with two-level resolution are generated for fast convergence of active contour. Second, to recognize the variations of face between successive frames and remove the neighbor background, weighted composite gradient map is generated by combining the composite gradient map and difference mask of previous and current frames. Third, to prevent active contour from converging local minima, the energy slope is generated by using closing operation. In addition, the fast closing operation is proposed to accelerate the processing time of closing operation. For performance evaluation, we compare our method with previous active contour model-based face tracking methods using a visual inspection, robustness test and processing time. Experimental results show that our method can effectively track the face with large movement and robustly converge to the optimal position even in frames with complicated background.

Objective Assessment of Mathematical Morphology Operators to Improve the Accuracy of Background Subtraction for Soccer Videos: An Experimental Comparative Study (축구 동영상의 배경 분리 정확도 향상을 위한 수학적 모폴로지 연산자들의 정량적 비교 평가에 관한 연구)

  • Jung, Chanho
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.41 no.12
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    • pp.1752-1755
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    • 2016
  • In this letter, to determine how mathematical morphology operators can be best used to enhance the accuracy of background subtraction for "soccer videos", we conducted an experimental comparative study. We investigated six different mathematical morphology operators under the same experimental setup. We found that the closing by reconstruction-opening by reconstruction is optimal through the experiments using the F-measure. We believe that this comprehensive comparative study serves as a reference point and guide for developers and practitioners in choosing an appropriate mathematical morphology operator adopted for building intelligent soccer video analysis systems.

Role of Intraoperative Angiography in the Surgical Treatment of Cerebral Aneurysms (뇌동맥류의 수술 중 뇌혈관 조영술의 역할)

  • Sim, Jae Hong
    • Journal of Korean Neurosurgical Society
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    • v.29 no.4
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    • pp.491-499
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    • 2000
  • Objective : In the cerebral aneurysm surgery, the goal is complete circulatory exclusion of the aneurysm without compromise of normal vessels. In an operating room, an operator should confirm the completeness and precision of the surgical result, before closing the wound. Object of this study was to determine which cases require intraoperative angiography. Methods : We reported our experience with 48 intraoperative angiographic studies performed during the surgical treatment of cerebral aneurysm of these 48 cases. There were 5 giant(10.4%), 15 globular(1.5-2.5cm)(31.25%) and 28 saccular(58.3%) aneurysm. We recorded the incidence of unexpected findings, such as residual aneurysms, major vessel occlusions. Using Fischer's exact test, we assessed whether unexpected angiographic findings showed any correlation with aneurysm site, size and clinical findings. Results : In 5 cases(10.4%), we detected unexpected angiographic findings which resulted in clip adjustment. By means of clip adjustment, an operator could restore the flow of two major arterial occlusion(4.2%) and also obliterate three persistent filling aneurysms(6.3%). Globular aneurysm was the only factor to predict unexpected angiographic findings(p<0.05). The subgroup of globular and giant aneurysm has a high risk of occlusion of the parent artery and its branches and/or residual aneurysm. There were two minor complications related to this procedure. Conclusion : Intraoperative assessment makes it possible to recognize and correct the technical defect. Particularly in globular aneurysm, we were able to prevent both the chance for another operation and the risk of postoperative complications.

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Multi Characters Detection Using Color Segmentation and LoG operator characteristics in Natural Scene (자연영상에서 컬러분할과 LoG연산특성을 이용한 다중 문자 검출에 관한 연구)

  • Shin, Seong;Baek, Young-Hyun;Moon, Sung-Ryong
    • Journal of the Korean Institute of Intelligent Systems
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    • v.18 no.2
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    • pp.216-222
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    • 2008
  • This paper proposed the multi characters detection algorithm using Color segmentation and the closing curve feature of LoG Operator in order to complement the demerit of the existing research which is weak in complexity of background, variety of light and disordered line and similarity of left and background color, etc. The proposed multi characters detection algorithm divided into three parts : The feature detection, characters format and characters detection Parts in order to be possible to apply to image of various feature. After preprocess that the new multi characters detection algorithm that proposed in this paper used wavelet, morphology, hough transform which is the synthesis logical model in order to raise detection rate by acquiring the non-perfection characters as well as the perfection characters with processing OR operation after processing each color area by AND operation sequentially. And the proposal algorithm is simulated with natural images which include natural character area regardless of size, resolution and slant and so on of image. And the proposal algorithm in this paper is confirmed to an excellent detection rate by compared with the conventional detection algorithm in same image.

Multi-scale crack detection using decomposition and composition (해체와 구성을 이용한 다중 스케일 균열 검출)

  • Kim, Young Ro;Chung, Ji Yung
    • Journal of Korea Society of Digital Industry and Information Management
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    • v.9 no.3
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    • pp.13-20
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    • 2013
  • In this paper, we propose a multi-scale crack detection method. This method uses decomposition, composition, and shape properties. It is based on morphology algorithm, crack features. We use a morphology operator which extracts patterns of crack. It segments cracks and background using opening and closing operations. Morphology based segmentation is better than existing integration methods using subtraction in detecting a crack it has small width. However, morphology methods using only one structure element could detect only fixed width crack. Thus, we use decomposition and composition methods. We use a decimation method for decomposition. After decomposition and morphology operation, we get edge images given by binary values. Our method calculates values of properties such as the number of pixels and the maximum length of the segmented region. We decide whether the segmented region belongs to cracks according to those data. Experimental results show that our proposed multi-scale crack detection method has better results than those of existing detection methods.

Concrete crack detection using shape properties (형태의 특징을 이용한 콘크리트 균열 검출)

  • Joh, Beom Seok;Kim, Young Ro
    • Journal of Korea Society of Digital Industry and Information Management
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    • v.9 no.2
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    • pp.17-22
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    • 2013
  • In this paper, we propose a concrete crack detection method using shape properties. It is based on morphology algorithm and crack features. We assume that an input image is contaminated by various noises. Thus, we use a morphology operator and extract patterns of crack. It segments cracks and background using opening and closing operations. Morphology based segmentation is better than existing integration methods using subtraction in detecting a crack it has small width. Also, it is robust to noisy environment. The proposed algorithm classifies the segmented image into crack and background using shape properties of crack. This method calculates values of properties such as the number of pixels and the maximum length of the segmented region. Also, pixel counts of clusters are considered. We decide whether the segmented region belongs to cracks according to those data. Experimental results show that our proposed crack detection method has better results than those by existing detection methods.

Stereok Matching based on Intensity and Features for Images with Background Removed (배경을 제외한 영상에서 명암과 특징을 기반으로하는 스테레오 정합)

  • Choe, Tae-Eun;Gwon, Hyeok-Min;Park, Jong-Seung;Han, Jun-Hui
    • Journal of KIISE:Software and Applications
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    • v.26 no.12
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    • pp.1482-1496
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    • 1999
  • 기존의 스테레오 정합 알고리즘은 크게 명암기반기법과 특징기반기법의 두 가지로 나눌 수 있다. 그리고, 각 기법은 그들 나름대로의 장단점을 갖는다. 본 논문은 이 두 기법을 결합하는 새로운 알고리즘을 제안한다. 본 논문에서는 물체모델링을 목적으로 하기 때문에 배경을 제거하여 정합하는 방법을 사용한다. 이를 위해, 정합요소들과 정합유사함수가 정의되고, 정합유사함수는 두 기법사이의 장단점을 하나의 인수에 의해 조절한다. 그 외에도 거리차 지도의 오류를 제거하는 coarse-to-fine기법, 폐색문제를 해결하는 다중윈도우 기법을 사용하였고, 물체의 표면형태를 알아내기 위해 morphological closing 연산자를 이용하여 물체와 배경을 분리하는 방법을 제안하였다. 이러한 기법들을 기반으로 하여 여러가지 영상에 대해 실험을 수행하였으며, 그 결과들은 본 논문이 제안하는 기법의 효율성을 보여준다. 정합의 결과로 만들어지는 거리차 지도는 3차원 모델링을 통해 가상공간상에서 보여지도록 하였다.Abstract Classical stereo matching algorithms can be classified into two major areas; intensity-based and feature-based stereo matching. Each technique has advantages and disadvantages. This paper proposes a new algorithm which merges two main matching techniques. Since the goal of our stereo algorithm is in object modeling, we use images for which background is removed. Primitives and a similarity function are defined. The matching similarity function selectively controls the advantages and disadvantages of intensity-based and feature-based matching by a parameter.As an additional matching strategy, a coarse-to-fine method is used to remove a errorneous data on the disparity map. To handle occlusions, multiple windowing method is used. For finding the surface shape of an object, we propose a method that separates an object and the background by a morphological closing operator. All processes have been implemented and tested with various image pairs. The matching results showed the effectiveness of our method. From the disparity map computed by the matching process, 3D modeling is possible. 3D modeling is manipulated by VRML(Virtual Reality Manipulation Language). The results are summarized in a virtual reality space.