• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2013.10a
• /
• pp.94-96
• /
• 2013

본 논문에서는 복부 초음파 영상에서 Ends_in Search Stretching 기법을 적용하여 명암 대비를 강조한 후, 이진화, 영역 레이블링 기법, 잡음 제거를 통해 근막을 추출하고, 근막 영역의 하단 경계선을 기준으로 Cubic Spline 보간법을 적용하여 복부 근육의 근막 하단 영역을 추출한다. 복부 초음파 영상에서 추출된 근막 하단 영역을 이용하여 근막 영역을 제거한 후, 거리 기반 퍼지 ART 알고리즘을 적용하여 충수 후보 영역을 추출한 다. 추출된 충수 후보 영역에 침식 연산과 영역 레이블링 기법을 적용하여 충수를 추출한다. 제안된 방법을 복부 초음파 영상을 대상으로 실험한 결과, 기존의 충수 추출 방법보다 객관적이고 효율적으로 충수와 소장의 명암도 차이를 구별할 수 있어 충수 영역이 이전의 방법 보다 비교적 정확히 추출되는 것을 영상의학과 관련 전문의를 통해 확인하였다.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.19 no.11
• /
• pp.2540-2545
• /
• 2015

In this paper, we propose a novel method to extract appendix from ultrasound image automatically to avoid such subjectivity issue. In the process, we apply a series of image processing algorithms such as Ends_in search stretching for emphasizing brightness contrast and binarization, region labelling, and cubic spline interpolation for extracting lower bound fasicia line that is the base of extracting the appendix. Knowing that the appendix is located at the lower organ area below the bottom fascia line, we conduct a series of image processing techniques to find the fascia line correctly. And then we apply ART2 algorithm to the organ area in order to extract appendix accurately. Through experiment, the effectiveness of the proposed method is verified based on the field experts' evaluations.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2013.05a
• /
• pp.389-391
• /
• 2013

본 논문에서는 초음파 검사자가 효율적으로 충수염을 진단할 수 있도록 하기 위하여 초음파 영상에서 충수를 추출하는 방법을 제안한다. 충수를 추출하는 과정은 초음파 영상에서 Ends_in Search Stretching 기법을 적용하여 명암 대비를 강조하고, Max-Min 이진화, 영역 레이블링, 잡음 제거, Cubic Spline 보간법을 적용하여 복부 근육의 하단 근막 부분을 추출한다. 초음파 영상에서 추출된 근막 영역을 제거한 후, K-Means 클러스터링과 영역 레이블링을 적용하여 충수 영역을 추출한다. 제안된 방법을 초음파 영상을 대상으로 실험한 결과, 충수염을 진단하기에 적합한 충수 영역이 추출되는 것을 영상의학과 전문의를 통하여 확인하였다.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2013.10a
• /
• pp.889-892
• /
• 2013

본 논문에서는 급성 복증을 주소로 야간 응급실 내원 시 영상의학과 전문의 부재 등과 관련된, 급성 충수 돌기염 진단을 위한 복부 초음파 검사의 환자 대기 시간과 충수 돌기 절제술 시행까지 환자 대기 시간을 분석한다. 응급실 내원 환자 41.5%에서 초음파 검사 대기 시간은 10시간 이상으로 나타났고, 외래 내원 환자의 45.2%는 수술 대기 시간이 18시간 이상으로 나왔다. 이는 초음파 검사의 대기 시간이 수술 대기 시간에 영향을 미치는 것으로 카이제곱검증에서 유의하게 나왔다(p<0.05). 따라서 본 논문에서는 환자들의 대기 시간을 감소시키기 위한 방법으로 응급실 의료진의 초음파 검사 시행에 따른 유익성과 급성 충수 돌기염의 특징을 이용한 의료 영상 분석, 연구의 필요성을 제안한다.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.17 no.6
• /
• pp.1281-1285
• /
• 2013

In this paper, we propose a method to extract the area of appendix from ultrasonographic image via computational vision. A series of image processing techniques such as Ends-in search stretching for enhancing the brightness contrast, block binarization, grassfire algorithm for extracting lower part of fascia, and fuzzy sigma binarization method to finalize the appendix area are used to achieve our goal. The strength of this paper is using fuzzy sigma binarization instead of other binarization technique to handle the sensitivity of extracting the target area from regio hypogastrica. The experiment verifies the efficacy of the proposed method successfully.

• Journal of the Korean Society of Radiology
• /
• v.82 no.1
• /
• pp.182-193
• /
• 2021

Purpose To identify the features that can be used for differentiating appendicitis from non-appendicitis in pediatric patients with equivocal ultrasound (US) results. Materials and Methods A total of 53 pediatric patients (≤ 18 years old) with equivocal results on US examination for suspected appendicitis between November 2012 and October 2017 were included. US evaluation was conducted based on information retrieved from a predefined structured report form. Then, the likelihood of appendicitis was prospectively classified into five categories. The equivocal results were considered as grade 3 (indeterminate) and grade 4 (probably appendicitis). Results Of the 53 patients, 25 (47.2%) and 28 (52.8%) were classified into grade 3 and 4 groups, respectively. Among the individual US findings, increased vascularity of the appendiceal wall and peri-appendiceal fat infiltration were independent findings associated with the diagnosis of appendicitis (p = 0.005, p = 0.045, respectively) in the multivariate logistic regression analysis and showed the highest diagnostic accuracy (69.8% and 62.3%, respectively). Conclusion Increased vascularity within the appendiceal wall and peri-appendiceal fat infiltration were significant predictors of appendicitis in patients with equivocal US findings.

• Journal of the Korean Society of Radiology
• /
• v.84 no.3
• /
• pp.653-662
• /
• 2023

Purpose This study aimed to determine the incremental value of using a structured report (SR) for US examinations of the pediatric appendix. Materials and Methods Between January 2009 and June 2016, 1150 pediatric patients with suspected appendicitis who underwent US examinations of the appendix were included retrospectively. In November 2012, we developed a five-point scale SR for appendix US examinations. The patients were divided into two groups according to the form of the US report: free-text or SR. The primary clinical outcomes were compared between the two groups, including the rate of CT imaging following US examinations, the negative appendectomy rate (NAR), and the appendiceal perforation rate (PR). Results In total, 550 patients were included in the free-text group and 600 patients in the SR group. The rate of additional CT examinations decreased by 5.3% in the SR group (8.2%, p = 0.003), and the NAR decreased by 8.4% in the SR group (7.8%, p = 0.028). There was no statistical difference in the appendiceal PR (37.6% vs. 48.0%, p = 0.078). Conclusion The use of an SR to evaluate US examinations for suspected pediatric appendicitis results in lower CT use and fewer negative appendectomies without an increase in appendiceal PR.

• Transactions of the Korean Society of Mechanical Engineers B
• /
• v.41 no.10
• /
• pp.675-683
• /
• 2017

In this study, a theoretical analysis was performed to the flow of refilling stage in a safety injection tank, which is the core cooling system of nuclear power plant in an emergency. A theoretical model was proposed with a nonlinear governing equation defining on the flow of the refilling process of the coolant. Utilizing the Taylor-series expansion, the $1^{st}$ - order approximation flow equation was obtained, along with its analytic solution of closed type, which could predict accurately the variations of free surface height and flow rate of the coolant. The availability of theoretical result was confirmed by comparing with previous experimental results.

• Proceedings of the KSME Conference
• /
• 2005.11a
• /
• pp.103.1-103.1
• /
• 2005

• Proceedings of the Korean Nuclear Society Conference
• /
• 1998.05a
• /
• pp.629-634
• /
• 1998

프랑스 CEA 실험장치인 BETHSY 실험설비에서 수행된 부분충수 운전에 대한 실험인 6.9c 실험에 대한 MELCOR 1.8.3 의 평가를 수행하였다. 이 연구는 OECD/NEA 국제공동연구인 ISP-38 로 수행되었다. 평가결과, MELCOR 1.8.3 은 부분충수운전시 잔열제거계통 상실에 대한 예측능력이 있고 원자로 냉각재계통압력, 노심수위 등 전반적으로 거동을 잘 모의하고 있다고 판단되었다. 그러나 민감도 분석에서 도출된 결론에 의하여 상간의 운동량 전달 및 Liquid Entrainment모델에 있어서 개선 필요성이 있는 것으로 평가되었다.