• Title/Summary/Keyword: Roberts

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Congenital Quadricuspid Semilunar Valve - A case report - (선천성 사엽성 반월형 판막 - 1예 보고 -)

  • Seo, Min-Bum;Seo, Hong-Joo
    • Journal of Chest Surgery
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    • v.42 no.3
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    • pp.361-363
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    • 2009
  • A 17-year-old male patient was referred with symptoms of dyspnea. Multi-detector computerized tomography (MDCT) and echocardiography evaluation revealed quadricuspid aortic and pulmonary valves, an atrial septal defect (ASD), and pulmonary stenosis. We closed the ASD using a bovine patch and performed a commissurotomy of the pulmonary valve. Quadricuspid semilunar valves are very rare congenital abnormalities that are reported to occur nine times more frequently in the pulmonic valve than in the aortic valve. According to the Hurwitz Roberts classification, the aortic valve was type A, and the pulmonic valve was type B. The aortic valve normal function, but the pulmonic valve was stenotic and had abnormal function.

Characterization of Elastic Modulus and Work of Adhesion in Elastomeric Polymer through Micro Instrumented Indentation Technique (마이크로 압입시험기법의 응용을 통한 탄성체 고분자 소재의 역학적 특성화 및 계면 접합에너지 평가기법 연구)

  • Lee, Gyu-Jei;Kang, Seung-Kyun;Kang, In-Geun;Kwon, Dong-Il
    • Proceedings of the KSME Conference
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    • 2007.05a
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    • pp.1744-1748
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    • 2007
  • In this study, the Johnson-Kendall-Roberts (JKR) theory was combined with the instrumented indentation technique (IIT) to evaluate work of adhesion and modulus of elastomeric polymer. Indentation test was used to obtain the load-displacement data for contacts between Tungsten Carbide indenter and elastomeric polymer. And the JKR contact model, contrived to take viscoelastic effects of polymer into account, was applied to compensate the contact area and the elastic modulus which Hertzian contact model would underestimate and overestimate, respectively. Besides, we could obtain the thermodynamic work of adhesion by considering the surface energy in this contact model. In order to define the relation between JKR contact area and applied load without optical measuring of contact area, we used the relation between applied load and contact stiffness by examining the correlation between JKR contact area and stiffness through dimensional analysis with 14 kinds of elastomeric polymer. From this work, it could be demonstrated that the interfacial work of adhesion and elastic modulus of compliant polymer can be obtained from a simple instrumented indentation testing without area measurement, and provided as the main algorithm of compliant polymer characterization.

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The Application and Effect of the Brown-Roberts-Wells Stereotactic System in the Management of Intracranial Lesions (두개강내 질환에서 BRW 콤퓨터 정위수술장치의 적용과 효과에 관한 연구)

  • Moon, Choong-Bae;Kim, Wan-Shup;Ko, Sam-Kyu;Ihm, Jowa-Hyuk;Baek, Seung-Chan;Chi, Yung-Chul;Choi, Byung-Yearn;Cho, Soo-Ho
    • Journal of Yeungnam Medical Science
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    • v.3 no.1
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    • pp.53-62
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    • 1986
  • In the past 10 years, modern technology has made deep seated obscure lesions visible. With development of computer technology and various stereotaxic techniques, many new procedures. refinement of old procedures, and development of new applications are possible. The authors are intended to provide a detailed description of our experience with the Brown-Roberts-Wells(BRW) stereotactic system in the evaluation and management of 90 patients with intracranial lesions, and to provide cases presentation of various inaccessible intracranial lesions.

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A Study on Edge Detection Algorithm using Modified Morphology (변형된 모폴로지를 이용한 에지 검출 알고리즘에 관한 연구)

  • Lee, Chang-Young;An, Young-Joo;Kim, Nam-Ho
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2015.05a
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    • pp.929-931
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    • 2015
  • As the digital image processing technology develops, the edge in the image is widely utilized in various fields such as the object recognition and detection. Most of the current methods to detect the edge use the fixed weighting mask of Sobel or Roberts. Such current methods have an advantage that the implementation is simple but have a disadvantage that the characteristics of the edge detection are more or less insufficient. Thus, an algorithm using the modified morphology is proposed in order to supplement such problems of the current edge detection methods and obtain the excellent edge detection, and also a simulation using this algorithm is conducted to compare with such current methods.

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A Study on Edge Detection Algorithm Considering Pixel Distribution (화소분포를 고려한 에지 검출 알고리즘에 관한 연구)

  • Lee, Chang-Young;Kim, Nam-Ho
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2015.05a
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    • pp.919-921
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    • 2015
  • The edge is widely utilized as a preconditioning process in order to simplify the images in several fields such as the object recognition and detection. The edge detection methods which are generally known include the methods of Sobel, Roberts and Laplacian. However, such current methods have an advantage that the implementation is simple but bring more less an insufficient result since they use the fixed weighting mask. Therefore, an algorithm using the modified morphology is proposed in order to supplement such problems of the current edge detection methods and obtain the excellent edge detection, and also a simulation using this algorithm is conducted to compare with such current methods.

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Edge Detection Algorithm using Area Averaging of Segmented Mask (세분화된 마스크의 영역 평균을 이용한 에지 검출 알고리즘)

  • Lee, Chang-Young;Kim, Nam-Ho
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2015.05a
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    • pp.267-269
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    • 2015
  • In the modern society, the images provide the most effective information in multi-devices and the edge includes important feature information in such images. This edge is used as an essential preconditioning process in several application fields and many studies have been carried out in order to obtain the excellent images. The methods of Sobel and Roberts which are generally known are simple to implement the images but bring more or less insufficient processing result. Thus, this paper proposed an edge detection algorithm using the area averaging of segmented mask in order to supplement the problems of the current methods and compared it with such current methods.

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Mechanical Characterization of Elastomeric Polymer Through Micro Instrumented Indentation Technique (마이크로 압입시험기법의 응용을 통한 탄성체 고분자 소재의 역학적 특성화 및 계면 접합에너지 평가기법 연구)

  • Lee, Gyu-Jei;Kang, Seung-Kyun;Kang, In-Geun;Kwon, Dong-Il
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.31 no.9
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    • pp.951-959
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    • 2007
  • In this study, the Johnson-Kendall-Roberts(JKR) theory was combined with the instrumented indentation technique (IIT) to evaluate work of adhesion and modulus of elastomeric polymer. Indentation test was used to obtain the load-displacement data for contacts between Tungsten Carbide indenter and elastomeric polymer. And the JKR contact model, contrived to take viscoelastic effects of polymer into account, was applied to compensate the contact area and the elastic modulus which Hertzian contact model would underestimate and overestimate, respectively. Besides, we could obtain the thermodynamic work of adhesion by considering the surface energy in this contact model. In order to define the relation between JKR contact area and applied load without optical measuring of contact area, we used the relation between applied load and contact stiffness by examining the correlation between JKR contact area and stiffness through dimensional analysis with 14 kinds of elastomeric polymer. From this work, it could be demonstrated that the interfacial work of adhesion and elastic modulus of compliant polymer can be obtained from a simple instrumented indentation testing without area measurement, and provided as the main algorithm of compliant polymer characterization.

A Study on Edge Detection for Images Corrupted by AWGN using Modified Weighted Vector (AWGN에 훼손된 영상에서 변형된 가중치 벡터를 이용한 에지검출에 관한 연구)

  • Lee, Chang-Young;Kim, Nam-Ho
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.16 no.7
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    • pp.1518-1523
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    • 2012
  • Due to development of visual media in various industrial sectors, the importance of image processing is increasing. Among the various image processing areas, edge detection is utilized widely for various fields such as object recognition, object segmentation, the medical and other industries. Edge includes the critical factors of images like size, direction and location. Then conventional methods such as Sobel, Prewitt, Roberts and Laplacian are proposed to detect edge. However, edge detection property of these methods is declined when they are applied to the image which corrupted by AWGN(Additive White Gaussian Noise). Therefore, an algorithm using modified weighted filter is proposed in this paper and our method has excellent property on edge detection.