• 제목/요약/키워드: Judgment Method

검색결과 529건 처리시간 0.028초

발전용 밸브누설 평가를 위한 다중계측 연구 (Study on the Multi-measuring Method for Evaluation of Internal Leak of Power Plant Valve)

  • 이상국;박성근;박종혁;김광홍;김영범
    • 동력기계공학회지
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    • 제11권3호
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    • pp.35-40
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    • 2007
  • Leak would happen because of the damage of high temperature and high-pressure valve in nuclear power plant. condition based prevention maintenance is essential by using the suitable method based on local condition. Energy loss prevention can prevent from an accurate test, Local actually and ability. The methods of test for high energy fluid leak at present are analysis of ${\Delta}T$, AE(Acoustic Emission) analysis, and thermal image. The result for test of secondary system in nuclear power plant Unit reveals that the AE occurred clearly in leakage situation, but thermal image didn't occur. It is identified that leak is occurred when the orifice located front and back of valve operates. It shows that making a impatient judgment by using the single method if it is leakage is containing uncertainty. So we think that using the Multi-Measuring method is more sound judgment than single-measuring method.

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재해 데이터베이스의 사례연구를 위한 휴먼에러 재해 검색방법에 관한 연구 (Study on searching method of human errors accidents for case study of disaster database)

  • 한우섭
    • 한국재난정보학회 논문집
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    • 제1권1호
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    • pp.121-136
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    • 2005
  • Most human-error case of accident database is written by various description and expression because accident database is produced by two or more person. And extracted information by searching of database varies in researcher's judgment criteria and the capability. Furthermore, much time and effort are required to examine manually information related to the human error from each accident case. Accordingly, it is difficult to explore objectively the accidents relevant to the human-error from the accident data base which is accumulated enormously. In this study, to solve these problems, it was developed an searchig method which is not influenced by researcher's judgment criteria and capability. For this, human-error keywords were extracted from a Japanese-English dictionary to examine objectively the accident case related to human-error in data base. This searching method by the human-error keywords can be applicable in most accident databases, although a database will be accumulated in future. Also, using the searching technique of this research, knowledge obtained by searching result can be compared with other research's results by the same method. Although the number of accident case increasese, searching results from database have the objectivity because it is not necessary to modify the based searching method or change the human-error keywords. However, as subject of future investigation, it would be necessary that the extension and investigation on human-error keywords improve and the technique to enhance searching accuracy would be modified.

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PVA를 이용한 산업용 모터 고장진단 모니터링 시스템의 가시성을 높이는 방법 (Method for High-visibility of Online Monitoring and Fault Diagnosis System for Industrial Motor using PVA)

  • 고영진;강인원
    • 대한안전경영과학회지
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    • 제22권1호
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    • pp.15-21
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    • 2020
  • Industrial Motors diagnostic equipment is highly dependent on the automation system, so if there are defects in the automation equipment, it can only rely on the operator's intuitive judgment.To help with intuitive judgment, Park's Vactor Approach(PVA) represents the current signal as a pattern of circles, so it can tell if a fault occurs when the circle is distorted. However, the failure to judge the degree of distortion of the circle pattern is the basis of the fault, so it will face difficulties. In this paper, in order to compare the faults of PVA, the period of d-axis current of PVA pulsation was mastered, so that two phase differences occurred in the same signal source. Through experiments, it is confirmed that this is a 90 degree cross formation of PVA, which is convenient for judging from the vision that there is no fault, thus helping the operator to make intuitive judgment.

업무상 뇌.심혈관질환의 인정기준에 관한 고찰 (Study on the Standards for Acknowledgement of Cerebral and Cardiovascular Diseases due to Occupational Cases)

  • 최순영;임화영
    • 대한안전경영과학회지
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    • 제12권3호
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    • pp.61-72
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    • 2010
  • Judgment of cerebral and cardiovascular diseases arising out of duty follows the legal judgment method for the purpose of investigation of medical causes based on the Industrial Accident Compensation Insurance Act, with the characteristics of the occurrence as personal factors etc. act as risk factors while work-related ones as triggers, in the case of disease due to occupational cases, as whether it arose out of duty must be judged including even the individual's personal risk factors, there are limitations securing fairness even with existing laws, regulations and guidelines. This study was carried out to suggest basic data for the preparation of standardized guidances for diseases arising out of duty by reviewing the standards for the acknowledgment of cerebral and cardiovascular diseases due to occupational cases, and it has a significance in that it suggests target diseases that may be judged as cerebral and cardiovascular diseases, legal criteria for the acknowledgment and standards for the judgment of cerebral and cardiovascular diseases arising out of duty.

간호시뮬레이션 학습자의 간호역량에 관한 구조모형 (A Structural Model on the Nursing Competencies of Nursing Simulation Learners)

  • 박수진;지은선
    • 대한간호학회지
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    • 제48권5호
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    • pp.588-600
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    • 2018
  • Purpose: The purpose of this study was to test a model of nursing competencies of nursing simulation learners. The conceptual model was based on the theory of Jeffries's simulaton theory. Methods: Data collection was conducted in October 2017 for 310 students from two nursing universities in Kyungbuk area for 20 days. Data analysis methods were covariance structure analysis using SPSS 21.0 and AMOS 22.0 statistical programs. Results: The hypothetical model was a good fit for the data. The model fit indices were comparative fit index=.97, normed fit index=.94, Tucker-Lewis Index=.97, root mean square error of approximation=.44, and standardized root mean square residual=.04. Teacher factors were directly related to simulation design characteristics, and it was confirmed that the curriculum, classroom operation and teaching method of the instructors were important factors. Learner factors were found to have a direct effect on nursing competence, self-confidence, and clinical performance that belong to nursing capacity. In particular, the results of this study indicate that the simulation design characteristics have a partial mediating effect on learner factors and clinical performance, and a complete mediating effect on learner factors and clinical judgment ability. Conclusion: In order to improve the learner's clinical performance and clinical judgment ability, it is necessary to conduct practical training through nursing simulation besides preparing the learner and the educator.

Multi-measuring기법을 이용한 원전 제어밸브의 누설진단 (Leakage Monitoring of Control Valves for Nuclear Power Plants Using Multi-measuring)

  • 김성영;김영범;김봉호;이상국
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2007년도 춘계학술대회B
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    • pp.3458-3463
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    • 2007
  • Leakage would happen because of the damage of high temperature and high-pressure valve in nuclear power plant. condition based prevention maintenance is essential by using the suitable method based on local condition. Energy loss prevention can prevent from an accurate test, Local actually and ability. The methods of test for high energy fluid leakage at present are analysis of ${\Delta}$T, AE(Acoustic Emission) analysis, and thermal image. The result for test of AC (Main steam) system in YNG 2 Unit reveals that the AE occurred clearly in leakage situation, but thermal image didn't occur. It is identified that leakage is occurred when the orifice located front and back of valve operates. It shows that making a impatient judgment by using the single method if it is leakage is containing uncertainty. So I think that using the Multi-Measuring method is more sound judgment than Single-Measuring method.

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S-PBL의 연계순서에 따른 간호대학생의 학습성과 비교: 무작위 교차설계 (A Comparative Study on Learning Outcomes according to the Integration Sequences of S-PBL in Nursing Students: Randomized Crossover Design)

  • 윤소영;최자윤
    • 대한간호학회지
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    • 제49권1호
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    • pp.92-103
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    • 2019
  • Purpose: This study aimed to compare the effects of simulation integrated with problem based learning (S-PBL) according to the sequences of problem-based learning (PBL) and high fidelity simulation training (HFS) on knowledge, clinical performance, clinical judgment, self-confidence, and satisfaction in fourth-grade nursing students. Methods: In this randomized crossover design study, four S-PBLs on medical-surgical nursing were applied alternatively to two randomly-assigned groups of 26 senior nursing students for 8 weeks. The collected data were analyzed using an independent t-test. Results: The method of administering PBL prior to HFS led to significantly higher scores on knowledge (t=2.28, p=.025) as compared to the method of administering HFS prior to PBL. However, the latter method led to significantly higher scores on clinical performance (t=-6.49, p<.001) and clinical judgment (t=-4.71, p<.001) as compared to the method of administering PBL prior to HFS. There were no differences in the effect of the two methods on self-confidence (t=1.53, p=.128) and satisfaction (t=1.28, p=.202). Conclusion: The integration sequences of S-PBL was associated with different learning outcomes. Therefore, when implementing S-PBL, it is necessary to consider the educational goal to executes an appropriate sequence of integration.

An Improved Multilevel Fuzzy Comprehensive Evaluation to Analyse on Engineering Project Risk

  • LI, Xin;LI, Mufeng;HAN, Xia
    • 융합경영연구
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    • 제10권5호
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    • pp.1-6
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    • 2022
  • Purpose: To overcome the question that depends too much on expert's subjective judgment in traditional risk identification, this paper structure the multilevel generalized fuzzy comprehensive evaluation mathematics model of the risk identification of project, to research the risk identification of the project. Research design, data and methodology: This paper constructs the multilevel generalized fuzzy comprehensive evaluation mathematics model. Through iterative algorithm of AHP analysis, make sure the important degree of the sub project in risk analysis, then combine expert's subjective judgment with objective quantitative analysis, and distinguish the risk through identification models. Meanwhile, the concrete method of multilevel generalized fuzzy comprehensive evaluation is probed. Using the index weights to analyse project risks is discussed in detail. Results: The improved fuzzy comprehensive evaluation algorithm is proposed in the paper, at first the method of fuzzy sets core is used to optimize the fuzzy relation matrix. It improves the capability of the algorithm. Then, the method of entropy weight is used to establish weight vectors. This makes the computation process fair and open. And thereby, the uncertainty of the evaluation result brought by the subjectivity can be avoided effectively and the evaluation result becomes more objective and more reasonable. Conclusions: In this paper, we use an improved fuzzy comprehensive evaluation method to evaluate a railroad engineering project risk. It can give a more reliable result for a reference of decision making.

Maritime Officers' Strategies for Collision Avoidance in Crossing Situations

  • Hong, Seung Kweon
    • 대한인간공학회지
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    • 제36권5호
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    • pp.525-533
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    • 2017
  • Objective: The aim of this study is to investigate maritime officers' strategies to avoid the ship collision in crossing situations. Background: In a situation where there is a risk of collision between two ships, maritime officers can change the direction and speed of the own-ship to avoid the collision. They have four options to select; adjusting the speed only, the direction only, both the speed and direction at the same time and no action. Research questions were whether the strategy they are using differs according to the shipboard experience of maritime officers and the representation method of ARPA (automatic radar plotting aid) - radar graphic information. Method: Participants were 12. Six of them had more than 3 years of onboard experience, while the others were 4th grade students at Korea Maritime and Ocean University. For each participant, 32 ship encounter situations were provided with ARPA-radar information. 16 situations were presented by the north-up display and 16 situations were presented by the track-up display. Participants were asked to decide how to move the own-ship to avoid the ship collision for each case. Results: Most participants attempted to avoid the collision by adjusting the direction of the ship, representing an average of 22.4 times in 32 judgment trials (about 70%). Participants who did not have experience on board were more likely to control speed and direction at the same time than participants with onboard experience. Participants with onboard experience were more likely to control the direction of the ship only. On the other hand, although the same ARPA Information was provided to the participants, the participants in many cases made different judgments depending on the method of information representation; track-up display and north-up display. It was only 25% that the participants made the same judgment under the same collision situations. Participants with onboard experience did make the same judgment more than participants with no onboard experience. Conclusion: In marine collision situations, maritime officers tend to avoid collisions by adjusting only the direction of their ships, and this tendency is more pronounced among maritime officers with onboard experience. The effect of the method of information representation on their judgment was not significant. Application: The results of this research might help to train maritime officers for safe navigation and to design a collision avoidance support system.

드라이빙 시뮬레이터 기반 자율주행차 판단능력 등급화를 위한 평가지표 선정 (Selection of Evaluation Metrics for Grading Autonomous Driving Car Judgment Abilities Based on Driving Simulator)

  • 오민종;진은주;한미선;박제진
    • 대한토목학회논문집
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    • 제44권1호
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    • pp.63-73
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    • 2024
  • 현재 전 세계적으로 연구·개발 중인 자율주행차 Level 3에서 Level 5단계는 운전자의 인지-판단-제어과정을 차량에 탑재된 각종 센서로 대체하여, 운전과정의 대부분을 인공지능이 자율적으로 수행할 수 있도록 한다. 하지만 현재 자율주행차는 국가별로 상이한 자율주행차의 판단능력 최소기준을 만족할 경우, 임시운행 허가를 받아 도로주행이 가능하도록 하고 있다. 향후 자율주행차가 보급될 때 구매자들은 임시운행 허가의 한계로 위험상황 회피능력에 대한 신뢰도가 높지 않을 것으로 예상된다. 이에 본 연구에서는 드라이빙 시뮬레이터 기반으로 운전자의 위험상황 회피능력 비교·평가를 통해 자율주행차 판단능력 등급화 방안 제시 및 시나리오별 등급화가 가능한 평가지표를 도출하고자 하였다. 드라이빙 시뮬레이터 실험에는 성인 30명(남=25, 여=5명)이 참여하였다. 실험결과 분석은 K-평균 군집분석과 독립표본 T-검정을 진행하였으며, 이를 통해 자율주행차의 판단능력 등급 분류가 가능함과 등급 분류의 통계적 유의성을 확인할 수 있었다. 향후 자율주행차의 위험상황 회피능력에 대한 신뢰수준을 향상시키는데 크게 기여할 수 있을 것이다.