인공 신경경망과 사례기반추론을 혼합한 지능형 진단 시스템

이길재,김창주,안병렬,김문현,Lee, Gil-Jae,Kim, Chang-Joo,Ahn, Byung-Ryul,Kim, Moon-Hyun 한국정보처리학회 2008 정보처리학회논문지B Vol.15 No.1

최근 IT 서비스 발달과 함께 고장제어, 고장의 원인분석 등의 복잡한 문제에 대하여 적합한 해결책을 제시할 수 있는 효과적인 진단시스템의 필요성이 커지고 있다. 따라서 본 논문에서는 지능형 진단 시스템분야에서의 시스템의 성능을 향상시키고, 최적의 진단을 수행하고자 사례기반추론과 인공신경망을 혼합한 지능형 진단 시스템을 제안 한다. 사례기반추론은 과거의 사례(경험)를 통해 현재의 제시된 문제를 해결하는 추론방식으로, 지식 획득이 덜 복잡하고, 정형화되기 어려운 규칙이나 문제영역이 불분명한 분야를 효율적으로 추론할 수 있다. 하지만 사례기반추론만을 이용해 추론된 사례는 증상에 대해 다수의 원인을 추론하게 된다. 이때 추론된 증상에 따른 다수의 원인은 동일한 가중치를 가져 불필요한 원인까지 진단해야 하는 문제점이 있다. 이러한 문제를 해결하고자 인공신경망의 오류역전파 학습 알고리즘을 이용하여 증상에 대한 원인들의 쌍을 학습 시킨 후 각각의 증상에 대한 원인의 가중치를 구해 제시된 증상에 대해 가장 발생 가능성이 높은 원인을 찾아내어, 보다 명확하고 신뢰성 있는 진단을 하는 데 그 목적이 있다. As the recent development of the IT services, there is a urgent need of effective diagnosis system to present appropriate solution for the complicated problems of breakdown control, a cause analysis of breakdown and others. So we propose an intelligent diagnosis system that integrates the case-based reasoning and the artificial neural network to improve the system performance and to achieve optimal diagnosis. The case-based reasoning is a reasoning method that resolves the problems presented in current time through the past cases (experience). And it enables to make efficient reasoning by means of less complicated knowledge acquisition process, especially in the domain where it is difficult to extract formal rules. However, reasoning by using the case-based reasoning alone in diagnosis problem domain causes a problem of suggesting multiple causes on a given symptom. Since the suggested multiple causes of given symptom has the same weight, the unnecessary causes are also examined as well. In order to resolve such problems, the back-propagation learning algorithm of the artificial neural network is used to train the pairs of the causes and associated symptoms and find out the cause with the highest weight for occurrence to make more clarified and reliable diagnosis.

경추후만을 동반한 극상근건염 환자의 추나치험1례

이길재,이병이,송윤경,임형호,Lee, Gil-Jae,Lee, Byeong-Yee,Song, Yun-Kyung,Lim, Hyung-Ho 척추신경추나의학회 2008 척추신경추나의학회지 Vol.3 No.2

Objective : The purpose of this study is to evaluate the conservative treatment for supraspinatus tendinitis with kyphotic cervical curvature patient. Methods : We used chuna, Herbal medication, Acupuncture, Bee Venom Acupuncture, Physical Therapy for this patient. And we measured of VAS score, ROM and Extent of the subjective symptoms of shoulder pain to evaluate treatment effects. Result : Patient's shoulder pain and cervical curvature has improved. VAS score and Extent of the subjective symptoms of shoulder pain score were also decreased.

봉약침 요법을 이용한 요추관 협착증 치험 1례

이길재,이병이,장건,송윤경,임형호,Lee, Gil-Jae,Lee, Byeong-Yee,Jang, Gun,Song, Yun-Kyung,Lim, Hyung-Ho 척추신경추나의학회 2007 척추신경추나의학회지 Vol.2 No.1

Objectives : This study was performed to evaluate the effect of Bee Venom Acupuncture Therapy on Lumbar Spinal Stenosis. Methods : The patient was diagnosed as Lumbar Spinal Stenosis through Lumbar spine MRI and treated with Bee Venom Acupuncture Therapy and so on and measured of VAS and ODI score to evaluate treatment effects. Results and Conclusions : ROM of Lumbar, Milgram test and sensory test has improved. VAS and ODI score were also decreased.

요추 추간판 탈출증 환자의 굴곡신연기법 치료효과에 대한 임상적 고찰

이길재,이병이,장건,송윤경,임형호,Lee, Gil-Jae,Lee, Byeong-Yee,Jang, Gun,Song, Yun-Kyung,Lim, Hyung-Ho 척추신경추나의학회 2007 척추신경추나의학회지 Vol.2 No.2

Objectives : This research is aimed to confirm the treating patients with herniated lumbar disc using Chuna treatment. Methods : Out of patients who were confirmed to have a herniated lumbar disc by MRI among the patients in oriental medical hospital of Kyungwon University from July 2005 to Dec 2006, we dived 15 people was treated common treatment, 15 people was treated both common treatment and Chuna treatment. We measured Visual Analog Scale(VAS) and symptom grade before and after treatment in each groups. Statistical analysis was performed by using SPSS program. Results : The result of the Visual Analog Scale(VAS) and symptom grade before and after treatment between two group, shows that the improvement of Back pain and Sciatica in common treatment with Chuna treatment group is more effective than that in only common treatment group.

마르텐사이트계 스테인리스강의 템퍼 취성과 준안정상에 관한 분석

이길재 ( Gil Jae Lee ),최병학 ( Byung Hak Choe ),김재훈 ( Jae Hoon Kim ) 한국열처리공학회 2021 熱處理工學會誌 Vol.34 No.1

The martensitic stainless steel has excellent corrosion resistance and higher strength by quenching and tempering heat treatment. It has been widely used as blade material due to these properties. The hardness and impact toughness of martensitic stainless steel depended strongly on tempering temperatures. The 12Cr martensite stainless steel (SS 410) tempered about 540℃ showed temper embrittlement. To know cause of temper embrittlement in terms of phase identification, a detailed analysis of electron diffraction patterns during TEM observations has been carried out on the <110>α-Fe and <113>α-Fe zone axes for temper embrittlement specimen. The double electron diffraction spots at 1/3(211) and 2/3(211) positions were observed. The lattice space between individual diffraction spots was about 3.5 A and this value coincide with three times to α-bcc lattice space (1.17 A). The area which found double diffraction spots was judged metastable “zone” similar to the omega phase and induced embrittlement of SS410 material. (Received January 4, 2021; Revised January 8, 2021; Accepted January 13, 2021)

고등교육의 책무성 평가 -회귀분석을 활용한 성과 기반 재정지원 방안 연구-

이길재(Lee Gil-Jae) 한국교육행정학회 2013 敎育行政學硏究 Vol.31 No.2

도심지에서의 GPS 가시성 분석에 관한 연구

이길재(Lee Gil Jae),최윤수(Choi Yun Soo),윤하수(Yoon Ha Su),김재명(Kim Jae Myeong) 대한토목학회 2009 대한토목학회 학술대회 Vol.2009 No.10

외상성 허리 탈장: 증례 보고

이길재 ( Gil Jae Lee ),정민 ( Min Chung ),유병철 ( Byung Chul Yu ) 대한외상학회 2013 大韓外傷學會誌 Vol.26 No.3

The occurrence of traumatic hernia is rare. However, traumatic lumbar hernias are the most frequently occurring traumatic hernias. Superior lumbar hernias occur more frequently than inferior lumbar hernias, but for anatomical reasons, among traumatic lumbar hernias, inferior lumbar hernias occur more frequently than superior lumbar hernias. Repair of a lumbar hernia is very difficult. Mesh fixation to the bony part and general weakness of surrounding tissue make repair of a lumbar hernia tricky. A traumatic lumbar hernia was repaired using transfascial fixation around the defect to secure the mesh. This technique is another choice for a lumbar hernia technique.

대학교육 만족도 및 교수학습 성과 영향요인 분석

이길재(Lee Gil-Jae),이정미(Lee Jung Mi) 한국교육행정학회 2015 敎育行政學硏究 Vol.33 No.1

본 연구의 목적은 대학 수준의 특성을 통제한 상태에서 대학생의 교수학습 과정과 관련된 변인들이 대학교육 만족도와 교수학습 성과에 어떠한 영향을 미치는지를 탐색하는 것이다. 이를 위해 한국교육개발원의 ‘대학생 교수-학습과정 조사도구(NASEL)’를 통해 수집된 2013년 도 데이터를 위계적 선형모형을 활용하여 분석하였다. 분석결과, 학생이 소속된 계열과 교수학습역량 진단기준(Benchmarks)은 대학교육 만족도와 유 의미한 상관을 보였다. 대학생 개인 수준 변수들을 살펴보면, 학년이 높아질수록, 아르바이트 시 간이 많을수록 더 낮은 대학교육 만족도를 보고하였다. 대학의 특성을 나타내는 2수준의 변수들 중에서 유일하게 학부명성 변수만 대학교육 만족도와 유의미한 상관을 나타냈다. 대학교육 만족 도 모형과 마찬가지로, 5개의 교수학습역량 진단기준과 소속 단과대학을 나타내는 계열 변수 는 교수학습 성과에도 통계적으로 유의미한 영향이 있는 것으로 드러났다. 학생의 개인 특성 변수 중 교수학습 만족도와 유의미한 상관을 보인 변수들은, 성별, 재학기간, 공부시간, 아르 바이트 시간, 장학금 수혜 액, 대학의 통제유형, 학부명성 등이었다. 이러한 분석결과를 토대 로 정책적 시사점이 논의되었다. The purpose of this study is to analyze the factors associated with students’ satisfaction with and learning outcomes of higher education. To achieve the goals, the study analyzes the data collected by running a survey of National Assessment of Students’ Engagement in Learning (NASEL) in 2013. Major findings are as follows: First, all the benchmarks are shown to be associated with students’ satisfaction at the statistical significance level of P<0.01. Concerning the student-level predictors, the higher the class level, the lower the satisfaction score. On the other hand, the more the amount of time spent for a part-time job, the lower the level of satisfaction. Next, the only institutional- level variable found to be related to students’ satisfaction is reputation of colleges. The results of the model analyzing variables associated with learning outcomes are as follows: As is the case for students’ satisfaction, five benchmarks are shown to be related to learning outcomes of college students. In terms of students’ characteristics, female students reveal a lower level of learning outcomes, whereas students with longer years of college education a higher level. As one can intuitively predict, the amount of time spent for a part-time job is shown to be negatively associated with learning outcomes, while higher GPA and greater amount of scholarship are found to be associated with learning outcomes in a positive way. At the institutional level, private and college reputation reveal a positive association with learning outcomes.

화력발전용 저압터빈 최종 단 블레이드에 대한 파손 연구

이길재(Lee Gil Jae),김진열(Kim Jin Yeol),김정환(Kim Jung Hwan),김정면(Kim Jeong Myun),김재훈(Kim Jae Hoon) 대한기계학회 2015 대한기계학회 춘추학술대회 Vol.2015 No.11

The fracture of a LP (low pressure) turbine blade of a 500 MW thermal power plant is presented. The blade was made of martensitic stainless steel and the micro structure was tempered martensite. There was no evidence of degradation of blade material but the hardness and impact properties of damaged blade were exceeded to material certificate specificaion. The fracture took place at root finger region and failure mode was intergranular type. The root cause for fracture was stress corrosion cracking due to material embrittlement.