Effective Scene Change Detection Method for MuIUmedia Bata as Video Images using Mean Squared Error

Jung, Chang-Ryul,Koh, Jin-Gwang,Lee, Joon The Korea Institute of Information and Commucation 2002 한국정보통신학회논문지 Vol.6 No.6

동영상데이터의 대용량 검색을 할 때 사용자가 원하는 검색점을 추출하여 인덱싱과 재생하기 위해서는 동영상 데이터의 프레임 리스트 제공이 필요하다. 평균오차를 적용하여 프레임의 대각선으로부터 픽셀값을 추출한다. 각각의 프레임으로부터 추출된 픽셀의 RGB값은 행렬구조로 저장하고, 저장된 프레임은 두 지정을 비교하여 장면전환점을 추출한다 또한 동영상의 전체적인 구조를 파악할 수 있는 알고리즘과 장면전환설을 구현하였다. 본 연구에서는 제안한 방법의 성능 우수성을 기존연구와 비교하여 분석하고 증명했다 When retrieving voluminous capacity of video image data, it is necessary to provide synopsized frame lists of video image data for indexing and replaying at the exact point where the user want to retrieve. We apply Mean Squared Error method to extract certain pixel value from diagonal direction of a frame. The RGB value of a pixel extracted from each frame is saved in a matrix form, and this frame is retrievedas a scene change point if the compared value of two points met the certain condition. Also implement the algorithm and provide a way to seize entire structure of video image and the point of scene changes. finally, we analyze and prove that our method has better performance compared with the others.

멀티미디어 영상 교육에 따른학습자 개인 특성에 대한 실증 분석

김동현,정창렬 順天靑巖大學 1998 論文集-順天靑巖大學 Vol.22 No.2

Recently, a few of educational institution are frequently used Multimedia Video System for the purpose of remote education according to constituting information super highway. The Multimedia Video System related to information super highway is feasible for real-time interaction on remote learning between instructor and learners, and enhances learning effects. Any learning media of education may be expected little learning effects without considering the system satisfactions of learner and the relation of learning effects using this Multimedia Video System. This paper is, therefore, analyzed the effects on correction and relation between the system satisfaction of Multimedia Video System and learning effects. And it is proposed reconsiderable contents of education to instructors or educational policy makers in using Multimedia Video System of remote education.

홍삼류의 섭취가 비만과 혈중 지질의 상호관계에 미치는 영향

박화진,이정희,이소진,함혜선,조현정,임창률,유영빈,박기현 대한의생명과학회 2000 Journal of biomedical laboratory sciences Vol.6 No.4

비만은 동맥경화의 위험인자로서 혈중에 triglyceride의 농도를 종가시키고, 상대적으로 HDL-Cholesterol의 농도를 감소시킴과 동시에 수축기 혈압을 상승시킨다. 본 연구에서 홍삼제품류를 4년 또는 5년 동안 복용해 온 건강한 사람 (ginseng군)과 홍삼제품을 복용하지 않은 건강한 사람 (control군)을 대상으로 하여 신체 계측치로부터 비만지수를 구하고 이것과 혈중의 triglyceride (TG)농도, TG/HDL-Cholesterol ratio 및 수축기 혈압과의 상호관계를 연구한 바, ginseng군에서는 대조군에 비해 혈중의 TG 농도가 일정하게 유지되었고, TG/HDL-Cholesterol ratio 및 수축기 혈압도 일정하게 유지되었다. 이러한 현상은 ginseng군에서 기호품으로 alcohol을 섭취하거나, 흡연을 한 경우에도 상관없이 일정하게 유지 되었다. 이 결과는 홍삼제품류를 장기 복용하면 비만의 저하 및 고혈압 또는 동맥경화의 위험인자가 억제될 수 있고, 결론적으로 비만, 고혈압 및 동맥경화를 예방할 수 있을 것으로 추정한다. Obesity is the risk fcactor of atherosclerosis and not only increases triglyceride concentration in blood but also decreases relatively the ratio of TG to HDL-Cholesterol in blood. In case of obesity, systolic blood pressure is also increased in responding the increase of TG in blood. Index of obesity in red ginseng-taking group (ginseng group) was lower as compared with non-red ginseng-taking group (control group). The TG concentration, the ratio of triglyceride to HDL-cholesterol in blood and systolic blood pressure were decreased in the subjects of ginseng group compared with that in control group. It is inferred that long-term intake of ginseng products may help to prevent the risk of atherosclerosis and obesity.

Nonlinear Cardiac Dynamics and Morning Dip : 위험한 일중리듬 An Unsound Circadian Rhythm

염명걸,김남수,오재원,김창렬,이재웅,김순길,이철범,노정일,최정연,윤용수 대한순환기학회 1998 Korean Circulation Journal Vol.28 No.3

전기차 드라이브샤프트 토크 전달 부의 열 구조 연동 해석

김세은(Se-Eun Kim),정창호(Chang-Ho Jung),이문구(Moon-Gu Lee),박정률(Jung-Ryul Park),한상원(Sang-Won Han),전용호(Yongho Jeon) 한국기계가공학회 2024 한국기계가공학회지 Vol.23 No.11

In recent years, the automotive industry has focused on developing electric vehicles (EVs) that meet the global carbon emission regulations. EVs have the potential to reduce emissions significantly by replacing fossil fuels with electric motors. However, unlike internal combustion engines, the high torque generated by the motor causes a considerable strain on the drivetrain, necessitating the development of new components capable of withstanding the load changes. This study aims to develop a drivetrain that can maintain stable performance under EV driving conditions. Traditional design validation requires significant time and cost. To address this challenge, we propose using numerical analysis to verify the design. Finite Element Analysis (FEA) was used to model the behavior of the torque transmission joints, focusing on the generation of frictional heat and accumulated thermal input owing to nonlinear motion and rotation. Simulations performed using LS-Dyna and ANSYS Transient Thermal software were compared with actual temperature measurement data, achieving a high accuracy of 98%. Nonlinear motion was predicted analytically and the reliability of the model was validated using thermal imaging camera data. Through this study, we analyzed the effects of heat flux on high-speed rotating objects, providing a solution that can shorten the design and development time.

혈액투석 유지 요법 환자에서 하대정맥 직경과 좌심실 비대와의 관계

신진호(Jin Ho Shin),박찬현(Chan Hyun Park),최정혜(Jung Hye Choi),이창화(Chang Hwa Lee),강경원(Kyoung Won Kahng),김상목(Sang Mok Kim),강종명(Chong Myung Kang),박한철(Han Chul Park),장성렬(Sung Ryul Chang),이방헌(Bang Hun Lee) 대한내과학회 1998 대한내과학회지 Vol.55 No.5

Background: Volume overload is one of the most important, correctable factor far blood sure control in hemodialysis patient. But objective parameter for the ideal body weight is not available in clinical field yet. Recently inferior vena caval examination became a possible candidate for an objective parameter for intravascular volume status. Therefore we investigated how inferior vena cava changes during hemodialysis compared with total amount of ultrafiltration and ANP, and also the effect of changes of IVC diameter on LVK Methods: 43 patients on stable maintainance hemodialysis were enrolled. Among them, 21 patients were on antihypertensive medication. Just before and after the hemodialysis, inferior vena cava diameter, plasma atrial natriuretic peptide and left ventricular mass index were measured for each patient. Inferior vena cava was examined at the level just below the hepatic vein during quiet respiration and left ventricular mass index was calculated. Results- Inferior vena cava at expiration(IVCe) was significantly decreased during hemodialysis(before hemodialysis 21.9 4.9 mm, after hemodialysis 18.3 4.4 mm, p = 0.02). Collasibility index was significantly increased during hemodialysis (before hemodialysis 0.24 0.15, after hemodialysis 0.41 0.19, p< 0.001). Atrial natriuretic peptide(ANP) was significantly decreased during hemodialysis (before hemodialysis 252.3±119.0 pg/ml, after hemodialysis 185.6±93.2 pg/ml, p<0.001). Total ultrafiltration amount was significantly correlated with collapsibility change(r=-0.40) and change of ANP(r=-0.41). Left ventricular mass index was correlated with interdialysis weight gain(r=0.39, p<0.05), IVCe after hemodialysis(r=0.48, p<0.05) in univariate analysis but not in multivariate analysis. Conclusion: Collapsibility index of inferior vena cava, IVC diameter and ANP changes reflect the volume change during the hemodiaylsis. Therefore 1VC examination can be an objective parameter for volume change during hemodialysis. Postdialysis 1VCe correlates weakly with left ventricular mass index but it cannot be an independant risk factor for left ventricular hypertrophy in our study.

An Agent System Protection Mechanism for Secure Action of Mobile Agent in Open Network Systems

Jung, Chang-Ryul,Yoon, Hong-Sang,Koh, Jin-Gwang The Korea Institute of Information and Commucation 2002 한국정보통신학회논문지 Vol.6 No.2

최근 몇 년간 이동에이전트는 분산시스템의 전자상거래와 전자데이터의 교환과 인공지능, 네트웍관리와 같은 여러 응용분야에서 많이 이용되고 있는 분야중 하나이다. 특히 EC/EDI의 영역에서 본래의 이동에이전트 서명 문제를 추가하여 사용되어야 한다. 그러므로 분산네트웍에서 이동하는 에이전트의 프라이버시와 속성을 보호하는 것은 매우 중요하다. 상거래에 응용되기 위해서는 각각의 이동에이전트들 상호간에 거래의 신뢰성을 향상할 수 있는 안전한 인트라넷 환경이 필요하다. 본 연구에서는 이동에이전트를 악의적인 서버로부터 이동에이전트를 자신을 보호하고 인터넷과 같은 오픈시스템의 자원들을 보호하는 안전한 이동에이전트 역할을 수행하도록 하는 에이전트 보호 메커니즘을 설계하여 신뢰하는 실행환경을 제안한다. In the resent years, the term mobile agent is probably one of the most overused words in many appliable areas of distributed open systems as electronic commerce and electronic data interchange, and it has very different meanings in the area of artificial intelligence, network management, or distributed systems. However, the use of mobile agent adds significant problems, primarily in the area of EC/EDI. Therefore it is very important to control the roaming agents to keep one's privacy or property in distributed open networks. The surge in secure intranets for commercial applications provides a robust, secure environment to which trading partners can increasingly entrust their interactions to some mobile agents. In this paper, we introduce a mechanism to protect mobile agent itself from the malicious server he is visiting and also we introduce a mechanism to protect vital resources of the open systems as internet.

Colonoscopy learning curves for colorectal surgery fellow trainees

Jung Ryul Oh,Kyung Su Han,Chang Won Hong,Byung Chang Kim,Bun Kim,Sung Chan Park,Min Jung Kim,Sang Jae Lee,Jae Hwan Oh,Changha Shin,Dae Kyung Sohn 대한외과학회 2018 Annals of Surgical Treatment and Research(ASRT) Vol.95 No.4

Purpose: This study aimed to analyze the learning curves for colorectal surgery fellows in a colonoscopy training program. Methods: Between May 2003 and February 2017, 60 surgical fellows joined our 1-year colonoscopy training program as trainees and performed 43,784 cases of colonoscopy. All trainees recorded their colonoscopy experiences prospectively into the database. After excluding 6 trainees, who had experience with performing more than 50 colonoscopies before participating in our training program or who discontinued our training program with experience performing less than 300 colonoscopies, this study included 54 trainees who had performed 39,539 colonoscopy cases. We analyzed the cecal intubation rate (CIR) and cecal intubation time (CIT) using the cumulative sum (Cusum) technique and moving average method to assess the technical colonoscopy competence. Results: Overall, the CIR by the trainees was 80.7%. The median number of cases of colonoscopy performed during the training period for each trainee was 696 (range, 322–1,669). The trainees were able to achieve a 90% CIR with 412 and 493 procedures when analyzed using the moving average and the Cusum, respectively. Using the moving average method, CIRs after 150, 300, and 400 procedures were 67.0%, 84.1%, and 89.2%, respectively. The CIT of trainees continuously decreased until 400 successful cases. Median CITs were 9.4, 8.3, and 7.4 minutes at 150, 300, and 400 successful cases, respectively. Conclusion: We found that more than 400 cases of experience were needed for technical competence in colonoscopy. Continuous teaching and monitoring is required until trainees become sufficiently competent.

Colonoscopy Learning Curves for Colorectal Surgery Fellow Trainees in the 15-year Experiences of a Colonoscopy Training Program

Jung Ryul OH,Kyung Su HAN,Chang Won HONG,Byung Chang KIM,Sung Chan PARK,Min Jung KIM,Jae Hwan OH,Changha SHIN,Dae Kyung SOHN 대한외과학회 2017 대한외과학회 학술대회 초록집 Vol.2017 No.11

Clinical and Radiographic Features of Adult-onset Ankylosing Spondylitis in Korean Patients: Comparisons between Males and Females

Jung, Young-Ok,Kim, Inje,Kim, Suho,Suh, Chang-Hee,Park, Han Jung,Park, Won,Kwon, Seoung Ryul,Jeong, Jae Cheon,Lee, Yun Jong,Ryu, Hee Jung,Park, Young Bae,Lee, Jisoo,Lee, You-Hyun,Seo, Young Il,Chung, The Korean Academy of Medical Sciences 2010 JOURNAL OF KOREAN MEDICAL SCIENCE Vol.25 No.4

<P>The objective of this study was to investigate clinical and radiographic features and gender differences in Korean patients with adult-onset ankylosing spondylitis. Multicenter cross-sectional studies were conducted in the rheumatology clinics of 13 Korean tertiary referral hospitals. All patients had a confirmed diagnosis of ankylosing spondylitis according to the modified New York criteria. Clinical, laboratory, and radiographic features were evaluated and disease activities were assessed using the Bath ankylosing spondylitis disease activity index. Five hundred and five patients were recruited. The male to female ratio was 6.1:1. Average age at symptom onset was 25.4±8.9 yr and average disease duration was 9.6±6.8 yr. Males manifested symptoms at a significantly earlier age. HLA-B27 was more frequently positive in males. Hips were more commonly affected in males, and knees in females. When spinal mobility was measured using tragus-to-wall distance and the modified Schober's test, females had significantly better results. Radiographic spinal changes, including bamboo spine and syndesmophytes, were more common in males after adjustment of confounding factors. In conclusion, we observed significant gender differences in radiographic spinal involvement as well as other clinical manifestations among Korea patients with adult-onset ankylosing spondylitis. These findings may influence the timing of the diagnosis and the choice of treatment.</P>