MFM-based alarm root-cause analysis and ranking for nuclear power plants

Song Mengchu,Reinartz Christopher,Zhang Xinxin,Thunem Harald P.-J.,McDonald Robert 한국원자력학회 2023 Nuclear Engineering and Technology Vol.55 No.12

Alarm flood due to abnormality propagation is the most difficult alarm overloading problem in nuclear power plants (NPPs). Root-cause analysis is suggested to help operators in understand emergency events and plant status. Multilevel Flow Modeling (MFM) has been extensively applied in alarm management by virtue of the capability of explaining causal dependencies among alarms. However, there has never been a technique that can identify the actual root cause for complex alarm situations. This paper presents an automated root-cause analysis system based on MFM. The causal reasoning algorithm is first applied to identify several possible root causes that can lead to massive alarms. A novel root-cause ranking algorithm can subsequently be used to isolate the most likely faults from the other root-cause candidates. The proposed method is validated on a pressurized water reactor (PWR) simulator at HAMMLAB. The results show that the actual root cause is accurately identified for every tested operating scenario. The automation of root-cause identification and ranking affords the opportunity of real-time alarm analysis. It is believed that the study can further improve the situation awareness of operators in the alarm flooding situation

A Study on the Concept and Features of K-fishbone Analysis in APEC e-Learning Training Program

Won-gyeum Cho,Young-hwan Kim APEC국제교육협력원 2019 Asia-Pacific Cybereducation Journal Vol.15 No.2

The purpose of this study is to examine the concepts and features of K-fishbone analysis used in the AeLT program and to find suggestions. For this purpose, I analyzed the AeLT Training Manual and lecture PPT file and AeLT final reports. The procedure of K-fishbone analysis is as follows. First, specify the problem to be solved. Second, brainstorm the cause and factor of the problem. Third, cluster problems and elements with the same factors. Fifth, the branching branches (2nd branch , 3rd branch) extending from large thorns become the sub-cause. After all the causes of the problem have been identified, the causal relationship and the correlational relationship are analyzed. The cause of receiving the most arrows is the fundamental cause and the priority of the solution. K-fishbone analysis should 1) consider as many causes and sub-factors as possible through brainstorming and 2) by doing casual and correlation relationship analysis, help to ① determine the more critical factors of the problem, ② remove unnecessary elements that hinder the discussion, so increase concentration on the subject, and ③ in the situation of the lack of data and information, improve the analyst's understanding of the problem and its causes. Moreover 3) It is suitable for solving problems especially in developing countries. The implications of K-fishbone analysis are as follows. First, it can be effectively used in invitational training for policy makers in developing countries. Second, it will be more widely used in inquiry classes in the school. Third, it can be widely extended and utilized as a method of RCA.

유압식 선로전환기의 Cause-consequence 분석에 관한 연구

이종규(Jong-Kyu Lee),최승호(Seung-Ho Choi) 한국철도학회 2013 한국철도학회 학술발표대회논문집 Vol.2013 No.11

선로전환기는 전기 모터식, 공압식 및 유압식 등이 있다. 선로전환기는 철도시스템의 핵심부품으로 고장이 발생하여 기능을 정확하게 동작하지 않을 경우 철도운용에 막대한 지장을 초래한다. 경부고속철도 2 단계(동대구-부산)에 Hydrostar 의 유압식 선로전환기가 설치되어 운용되고 있다. 이 유압식 선로전환기의 요구된 성능을 유지하기 위해서 Cause-consequece 분석을 필요로 한다. 본 논문에서는 유압식 선로전환기의 기능분석을 통한 모델링, FTA 를 수행하였으며, 각 기능에 대한 Cause-Consequence 분석을 수행하여 Cause-consequece diagram 을 도출하였다. The types of switch machine are electric motor, pneumatic and hydraulic. When the switch machine, which is the critical component of railway system, has a problem and does not work exactly, it results in enormous hindrance. The hydraulic switch machine of Hydrostar is installed at Gyeong-bu Highspeed Railway Project Phase Ⅱ(Dongdaegu - Pusan) and it is now operating. Cause-consequence analysis is required to maintain performance of hydraulic switch machine. This paper proposes a FTA analysis method that use the functional analysis of hydraulic point machine and presents Cause-consequence diagram by performing Cause-consequence analysis for each function.

Causes of Construction Delays of Apartment Construction Projects: Comparative Analysis between Vietnam and Korea

김영목,김수용,르드롱반,Kim, Young-Mok,Kim, Soo-Yong,Luu, Truong-Van Korea Institute of Construction Engineering and Ma 2008 건설관리 : 한국건설관리학회 학회지 Vol.9 No.5

Construction delay caused considerable losses to project parties. Avoiding construction delays is important to save costs for project stakeholders. The main objective of this paper is to identify major causes of construction delays of apartment construction projects in Vietnam. Sixteen causes of delay were identified through a questionnaire survey of 166 professionals. Factor analysis was employed to categorize these causes. The results of the survey revealed the main causes of delay of apartment projects in Vietnam are: (1) owner's and contractor'S financial difficulties; (2) lack of experienced contractors; (3) late delivery of materials; (4) late construction site handover; (5) owner's late payments for completed works; (6) low bid prices; (7) inappropriate construction method; and (8) defective works and unnecessary reworks. Factor analysis uncovered that causes of delay can be grouped under five categories labeled the five INs: incompetence, ineffectiveness, inadequateness, inapplicableness and inconceivableness. Comparative analysis between the Vietnam construction industry (VCI) and the Korea construction industry (KCI) has been performed to infer valuable lessons for researchers and practitioners in the VCI and the KCI. Comparative analysis indicated that main causes of delay in the VCI somewhat differ from main causes of delay in the KCI. However, "contractor'S financial difficulties", "late construction site handover", "unnecessary rework", "incapable designers", "site clearance difficulties" are common causes of delay in the VCI as well as the KCI. The findings of this research can be used as a guideline to overcome problems in the VCI as well as in other construction industries. Since Korea has emerged as the first largest foreign investor in Vietnam, the results of this study may be useful not only to practitioners and researchers in Vietnam but also to participants in Korea.

텍스트 마이닝 기법을 활용한 우리나라 산업재해의 원인분석

최기흥,Choi, Gi Heung 한국안전학회 2022 한국안전학회지 Vol.37 No.3

The analysis of the causes of accidents in workplaces where machines and tools are used is essential to improve the effectiveness and efficiency of safety prevention policies in places of employment in Korea. The causes of workplace accidents are not fully understood mainly due to difficulties in analyzing available descriptive information. This study focuses on the automated accident cause analysis in workplaces based on the accident abstracts found in industrial accident reports written in an unstructured descriptive format. The method proposed in this paper is based on text data mining and uses the keyword search function of Excel software to automate the analysis. The analysis results indicate that the primary reason for the frequency of accidents is related to technical aspects at a stage in which dangerous situations occur in the workplace. Accidents due to managerial causes are typically observed when danger exists in the workplace; however, managerial actions play a more important role in reducing accident severity. A small company tends to use unsafe machines and devices, leading to further accidents due to technical causes, whereas managerial causes are more conspicuous as the company grows. To preclude the occurrence of accidents due to inadequate knowledge, the implementation of safety management and the provision of safety education to elderly workers at the early stage of their employment are particularly important for small companies with less than 100 workers.

프로야구 구단의 공익연계마케팅 활동에 대한 성과 분석

이승철 ( Seung Chul Lee ) 한국스포츠산업경영학회 2009 한국스포츠산업경영학회지 Vol.14 No.1

국내외적으로 많은 프로스포츠구단이 기업의 사회적 공헌측면에서 공익연계마케팅활동을 실시하고 있지만 프로스포츠구단의 공익마케팅활동에 대한 성과를 분석하는 연구들은 매우 제한적으로 실시되고 있다. 따라서 이 연구는 프로야구단의 공익연계마케팅 활동을 분석하고자 팬들이 선호하는 공익연계마케팅활동이 무엇인지, 그리고 더 나아가 공익연계마케팅활동에 대한 팬들의 태도와 팀이미지, 팀동일시, 팀충성도 그리고 공익연계마케팅활동에 대한 후원의도와의 관계를 분석하였다. 이 연구의 대상은 2007년 프로야구 홈경기장에 직접 관람한 관중이다. 편의표본추출법을 이용하여 8개 팀의 홈경기장에서 총 2023명이다. 자료처리는 SPSS 16.0과 AMOS 16.0을 이용하여 빈도분석, 신뢰도분석, 상관관계분석, 공분산구조분석을 실시하였다. 연구결과를 살펴보면 다음과 같다. 첫째, 공익연계마케팅에 대한 태도는 팀이미지에 유의한 영향을 미치는 것으로 나타났다. 둘째, 공익연계마케팅에 대한 태도는 팀동일시에 유의한 영향을 미치는 것으로 나타났다. 셋째, 공익연계마케팅에 대한 태도는 팀충성도에 유의한 영향을 미치는 것으로 나타났다. 넷째, 팀이미지와 팀동일시는 팀충성도 영향을 미치는 것으로 나타났다. 여섯째, 팀충성도는 공익연계마케팅에 대한 후원의도에 유의한 영향을 미치는 것으로 나타났다. Expenditures on Cause related marketing (CRM) have grown dramatically in the past decade. Consumer tend to have favorable attitudes toward businesses that support charities or causes. CRM is a marketing concept that is increasingly gaining popularity among businesses globally today. Among the many benefits of CRM, businesses primarily aim at image improvements with the underlying assumption that image influences purchase intentions. CRM can be defined as a strategic positioning and marketing tool which links a company or brand to a relevant social cause or issue, for mutual benefit. It is a rapidly growing form of promotion that is expected to exceed $828 million in spending in North America in 2002. Nevertheless, cause related sport marketing has not received much academic attention in korea. Therefore, This study focused on the effects of professional baseball team`s caused-related marketing attitude on team image, team identification, and team loyalty, caused-related marketing supporting intention. The 2023 respondents in the study were spectators of the games of the 2007 Samsung Pavv baseball league. They were selected to achieve this purpose using non-probability sampling which is a convenient sampling method and a self-administrative method. Data analysis were processed through SPSS for Windows 16.0 and AMOS 16.0 version and analyzed by factor analysis, Cronbach`s α test, frequency analysis, correlation analysis, and structure equation modeling. The results of this study based on these methods and procedures are as follows. The attitude towards caused-related marketing had a positive influence on the team`s image, team identification, team loyalty. Second, team image and team identification had a positive influence on the teal loyalty and team loyalty had a positive influence on the supporting intention towards caused-related marketing

유아교사들이 인식하는 장애유아 학대의 유형과 원인에 관한 의미연결망 분석

김경민 한국복지상담교육학회 2020 복지상담교육연구 Vol.9 No.2

The purpose of this study was to obtain basic data for the organization of education programs for the abuse prevention of disabled infants and toddlers. To this end, the semantic structure of the types and causes of infantile abuse recognized by infant teachers was to be identified. Therefore, a questionnaire survey was conducted on 127 nursery teachers and kindergarten teachers working at daycare centers and kindergartens in Seoul and Gyeonggi-do. Based on the survey results, a frequency analysis of key words related to the types and causes of abuse of infants and toddlers with disabilities was conducted. In order to understand the structural characteristics of 60 key words related to abuse type and 25 key words related to abuse cause, UCINET6 and NetDraw program were used to conduct semantic network analysis, centrality and cluster analysis. As a result, in the centrality analysis, in the case of abuse type, the key words related to physical and emotional abuse were high, and in the cluster analysis, the importance of emotional abuse was derived. In the case of the cause of abuse, stress and lack of understanding of disability were high in centrality analysis, and in cluster analysis, the internal factor of teachers was found to be related to abuse. Based on these results, the composition of a program for preventing abuse of infant with disabilities for early childhood teachers was proposed. 본 연구는 유아교사들을 대상으로 장애유아 학대예방교육 프로그램을 구성하기 위한 기초자료를 확보하고자 하는 것을 목적으로, 유아교사들이 생각하는 장애유아 학대의 유형과 원인의 의미구조를 확인하고자 하였다. 이를 위해 서울, 경기지역의 어린이집과 유치원에 근무하는 보육 교사 및 유치원 교사 127명을 대상으로 설문조사를 실시하였다. 설문조사의 내용을 바탕으로 장애유아 학대의 유형 및 원인과 관련 있는 핵심어의 빈도분석을 실시하였다. 그리고 학대유형 관련 핵심어 60개와 학대원인 관련 핵심어 25개의 구조적 특성을 파악하기 위해 UCINET6와 NetDraw 프로그램을 사용하여 의미연결망 분석과 중앙성 및 군집분석을 실시하였다. 그 결과, 중앙성 분석에서는 학대 유형의 경우 신체적, 정서적 학대와 관련된 핵심어가 높게 나타났고 군집분석에서는 정서적학대의 중요성이 도출되었다. 학대 원인의 경우 중앙성 분석에서는 스트레스와 장애이해 부족이 높게 나타났으며 군집분석에서는 교사의 내적 요인이 학대와 관련 있는 것으로 나타났다. 이러한 결과를 바탕으로 유아교사를 위한 장애유아 학대 예방교육 프로그램의 구성 내용을 제안하였다.

TRIZ의 모순을 이용한 트랜스퍼 몰딩 프레스 장비 신뢰성 문제 해결

고수연,송용원,심홍균,전용문,서성민 사단법인 한국융합기술연구학회 2023 아시아태평양융합연구교류논문지 Vol.9 No.9

METAVERSE와 Chat GPT의 상용화에 따른 관련 산업이 발달함에 따라 고성능 반도체의 수요 또한 증가하고 있다. 이러한 고성능 반도체는 매우 정밀하게 제조된다. 정밀한 제조에 아주 작은 문제의 발생은 치명적이다. 이러한 이유로 반도체 제조공정에서 발생하는 문제는 모두 근본 원인을 찾아 제거해야 한다. 본 논문에서는 반도체 후공정 중 하나인 인캡슐레이션(Encapsulation) 공정의 성형 수지인 에폭시 몰드 컴파운드(EMC : Epoxy Mold Compound) 누출 발생에 따른 생산 불량 사례를 다루고 있다. 낮은 온도와 용융점이라는 근본 원인을 찾기 위해 TRIZ의 대표적 분석 방법인 기능 분석과 CECA(Cause–Effect Chain Analysis) 분석을 이용하였다. 여러 가지 영향 인자들의 기능적 상호 작용을 나타내는 기능도를 작성하여 영향을 분류하였으며, 분류된 내용을 바탕으로 영향 인자의 원인을 찾아 CECA 분석으로 세밀하게 분석하였다. 분석된 참 원인은 기술적 모순을 바탕으로 물리적 모순을 도출하였으며, 부분과 전체의 분리 원리를 활용하여 펠릿(Pellet) 형태의 EMC를 분말(Powder) 형태로 변형시켜 기존 공정 온도를 유지하면서 낮은 점도의 용융물로 변형시킬 수 있는 구체적인 해결안을 제시하였다. 그 결과 EMC의 누출이 획기적으로 개선되었으며, 그에 따른 사출물(Spiral Flow) 유동성 검사의 신뢰성이 향상되었다. Demand for high-performance semiconductors is increasing as related industries develop with the commercialization of METAVERSE and Chat GPT. Such high performance semiconductors are manufactured with great precision. A very small problem in precision manufacturing can be catastrophic. Therefore, the root cause of any problem that occurs in the semiconductor manufacturing process is found and eliminated. This paper deals with cases of production defects caused by leakage of epoxy mold compound (EMC), which is a molding resin in the encapsulation process, which is one of the semiconductor post-processes. In order to find the root cause of low temperature and melting point, we used functional analysis and CECA (Cause-effect chain analysis) analysis, which are representative analytical methods of TRIZ. The effects of various influencing factors were functionally created, functional diagrams showing interactions were created and classified, and the causes of influencing factors were found based on the classified contents and analyzed in detail by CECA analysis. The analyzed true cause derives physical contradiction based on technical contradiction, utilizes part-whole separation principle to transform pellet-like EMC into powder form, low viscosity while maintaining existing process temperature presented a concrete solution that can be transformed into a melt of As a result, leakage of the epoxy mold compound was dramatically improved, thus improving the reliability of the injection fluidity test.

근본원인분석을 적용한 간호대학생의 환자안전의 효과

신정은,김혜련 한국간호시뮬레이션학회 2018 한국간호시뮬레이션학회지 Vol.6 No.1

Purpose: The purpose of this study was to examine the effect of debriefing program applying patient safety analysis and comparison of knowledge and attitude toward patient safety. Method: A nested design of pretest-posttest control group was used with root cause analysis for debriefing. The participants were 58 undergraduate nursing students recruited from one university in Chungcheong province. They were assigned to either an experimental group (n=28 or a control group (n=30). A structured root cause analysis method for debriefing program offered to the experimental group whereas the control group did not receive any program. The data were analyzed using the PASW 23.0 program with χ2test, t-test, and ANOVA. Results: The participants who had participated in the root cause analysis in the debriefing showed significant difference (p < .001). Conclusion: The result of this study found that the root cause analysis method in the debriefing improved patient safety. Therefore, this program can be widely used in nursing curriculum because it leads to efficient debriefing and improves patient safety through root cause analysis.

선박 충돌사고의 원인요소 간 상관관계 및 충돌시간에 따른 원인요소 분석

윤동협,신일식 해양환경안전학회 2017 해양환경안전학회지 Vol.23 No.1

선박의 대형화, 고속화 및 선종의 다양화는 운송수단 중 해양 운송수단의 비중을 크게 증가시켰다. 선박사고 유형 중 기관손상 다음으로 충돌이 사고발생 빈도가 높았으며, 인적 요인에 의한 사고비율이 높은 것으로 보고되고 있다. 선박 충돌사고는 한 가지 원인요소로 발생하는 경우보다 복합적인 원인요소로 발생하게 되며 여러 개의 원인요소를 재결서를 통하여 원인요소를 조사할 필요가 있다. 본 연구에서는 해양안전심판원에서 제공하는 재결서 중 선박 충돌사고에 대해서 인적 요인을 바탕으로 선박 충돌사고의 원인요소를 도출하였으며, 상관관계분석을 통하여 원인요소들을 규명하였다. 또한, 선박충돌을 인지한 시점에서부터 충돌이 일어난 시점까지 걸린 시간을 바탕으로 충돌을 피할 수 없는 충돌시점에서의 발생되는 주요 원인요소와 20분 내에 발생하는 선박 충돌사고의 원인요소를 분석하여 선박 충돌사고를 예방하고자 하였다. 상관분석은 상용소프트웨어인 Statistical Package for Social Sciences(SPSS Ver21.0)을 사용하였다. 시간 분석은 재결서를 바탕으로 상대방 선박을 인지한 시점에서부터 충돌이 일어난 시점까지 걸린 시간을 분석하였다. 선박 충돌사고의 원인요소는 2가지 이상에 의해 발생한 사고가 많았으며, 상대선박 감시소홀은 항해업무 외 다른 작업과 높은 상관관계가 있었다. 충돌을 피할 시간 여력이 없는 경우(0분)이 36.1 %이며, 경계 또는 상대 선박 감시소홀과 졸음항해 또는 음주가 원인요소이었다. Enlargement and speed-up of a ship and diversification of ship’s type have served to greatly increase the importance of marine transport means. It's reported that accident occurrence frequency of collision is high next to engine damage among the ship accident types, and that the accident ratio according to human factors is also high. In addition, ship accidents come to occur caused by complex cause factors rather than a sole cause factor, it is necessary to investigate the cause factors through the written verdict. This study proposed the cause factors of collision ship accident on the basis of human factors in collision ship accident among the written verdicts provided by the Korean Maritime Safety Tribunal, and inquired into the cause factor and effect through the correlation analysis of accident occurrence factors. Also, this study predicted the collision accident through analyzed the major cause factor of the occurrence at the zero minute when collision on the basis of the time taken from the time point of detecting collision of ships to the time point of collision occurrence. This study used commercial software-Statistical Package for Social Sciences (SPSS Ver21.0) to do correlation analysis. For time analysis, this study analyzed the cause factor and time by analyzing the time taken from the time point of detected ships to the time point of collision occurrence on the basis of the written verdicts. The study analysis showed that there were many cases of collision ship accidents occurrence caused by more than two sorts of cause factors, and that the case (zero minute) where there is no time to spare for collision avoidance accounted for 36.1 %, and negligence in guard or surveillance of the other ship, and sailing while drowsy, or drinking was a contributor to an accident. Poor watch keeping is very strong relationship with pool ready for sail.