• 제목/요약/키워드: Accuracy Assessment

검색결과 1,599건 처리시간 0.028초

A rapid modeling method and accuracy criteria for common-cause failures in Risk Monitor PSA model

  • Zhang, Bing;Chen, Shanqi;Lin, Zhixian;Wang, Shaoxuan;Wang, Zhen;Ge, Daochuan;Guo, Dingqing;Lin, Jian;Wang, Fang;Wang, Jin
    • Nuclear Engineering and Technology
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    • 제53권1호
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    • pp.103-110
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    • 2021
  • In the development of a Risk Monitor probabilistic safety assessment (PSA) model from the basic PSA model of a nuclear power plant, the modeling of common-cause failure (CCF) is very important. At present, some approximate modeling methods are widely used, but there lacks criterion of modeling accuracy and error analysis. In this paper, aiming at ensuring the accuracy of risk assessment and minimizing the Risk Monitor PSA models size, we present three basic issues of CCF model resulted from the changes of a nuclear power plant configuration, put forward corresponding modeling methods, and derive accuracy criteria of CCF modeling based on minimum cut sets and risk indicators according to the requirements of risk monitoring. Finally, a nuclear power plant Risk Monitor PSA model is taken as an example to demonstrate the effectiveness of the proposed modeling method and accuracy criteria, and the application scope of the idea of this paper is also discussed.

Screening and Assessment Tools for Measuring Delirium in Patients with Cancer in Hospice and Palliative Care: A Systematic Review

  • Yang, Eun Jung;Hahm, Bong-Jin;Shim, Eun-Jung
    • Journal of Hospice and Palliative Care
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    • 제24권4호
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    • pp.214-225
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    • 2021
  • Purpose: This study reviewed screening and assessment tools that are used to measure delirium in patients with cancer in hospice and palliative care settings and examined their psychometric properties. Methods: Four databases were searched for studies using related search terms (delirium, tools, palliative care, cancer, and others). The inclusion criteria were a) studies that included screening/assessment tools for measuring delirium in cancer patients receiving hospice/palliative care, and b) studies published in English or Korean. The exclusion criteria were a) studies that were conducted in an intensive care setting, and b) case studies, qualitative studies, systematic reviews, or meta-analyses. Results: Out of the 81 studies identified, only 10 examined the psychometric properties of tools for measuring delirium, and 8 tools were ultimately identified. The psychometric properties of the Memorial Delirium Assessment Scale (MDAS) were the most frequently examined (n=5), and the MDAS showed good reliability, concurrent validity, and diagnostic accuracy. The Delirium Rating Scale had good reliability and diagnostic accuracy. The Delirium Rating Scale-Revised 98 also showed good reliability and structural validity, but its diagnostic performance was not examined in hospice/palliative care settings. The Nursing Delirium Screening Scale showed relatively low diagnostic accuracy. Conclusion: The MDAS showed evidence of being a valid assessment tool for assessing delirium in patients with cancer in palliative care. Few studies examined the diagnostic performance of delirium tools. Therefore, further studies are needed to examine the diagnostic performance of screening/assessment tools for the optimal detection of delirium in patients with cancer in hospice/palliative care.

고해상도 영상자료 및 객체지향분류기법을 이용한 식생분류 정확도 향상 방안 연구 (Accuracy Improvement of Vegetation Classification Using High Resolution Imagery and OOC Technique)

  • 홍창희;박종화
    • 환경영향평가
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    • 제18권6호
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    • pp.387-392
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    • 2009
  • As Our society's environmental awareness and concern the significant increases, the importance of the legal system for environmental conservation such as the Prior Environmental Review System, Environmental Impact Assessment is growing increasingly. but, still critical issues are present such as reliability. Though there could be various causes such as the system or procedures etc. Above all, basically the environmental data problem is the critical cause. Therefore, this study was trying to improve the environmental data accuracy using the high-resolution color aerial photography, LiDAR data and Object Oriented Classification method. And in this study, classification based on coverage percentage of a particular species was attempted through the multi-resolution segmentation and multi-level classification method. The classification result was verified by comparison with 11 points local survey data. All 11 points were classified correctly. And even though the exact coverage percentage of the particular species did not be measured, It was confirmed that the species was occupied similar portion. It is important that the environmental data which can be used for the conservation value assessment could be acquired.

신뢰성해석에 의한 초기균열을 갖는 구조부재의 건전성 평가방법 (The Integrity Assessment Method of Initailly Cracked Structural Components by Reliability Analysis)

  • 임상전;변태욱
    • 대한조선학회논문집
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    • 제30권2호
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    • pp.161-176
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    • 1993
  • 본 논문에서는 주어진 상황에 맞추어 적절한 수준에서 건전성평가를 수행하기 위하여, 개정된 BSI PD 6493의 3단계 평가방법에 균열성장효과를 고려한 건전성 평가방법과 균열의 안정성장을 엄밀히 고려할 수 있는 안정성 평가방법(stability assessment method:SAM)과 더불어 소성 붕괴를 평가하는 극한하중해석을 고려한 건전성 평가방법을 정식화하였다. 또한 신뢰성이론 중 2차 모멘트방법을 사용하여, center cracked panel(CCP) 시편과 관통균열을 갖는 파이프에 대하여, 신뢰성해석에 의한 건전성 평가를 수행하였다. 신뢰성해석을 수행하는데 필요한 확률변수들의 통계적 특성은 지금까지 보고된 그들 변수들의 실험자료와 통계해석의 결과들을 이용하였다. 또 기존의 신뢰성해석에서 정확한 파괴확률을 구할 수 있는 Monte Carlo 방법을 사용하여, 본 논문의 유용성을 검토하였다.

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Establishment of analytical methods for allergenic compounds in mouthwashes and sanitary napkins by ultra-high-performance liquid chromatography with tandem mass spectrometry

  • Hee-Jung Sim;Hee-Jin Jeong;Yeong-In Lee;Yu-Jin Cho;Seung-Hoon Baek;Jong-Hwan Kim
    • 분석과학
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    • 제36권2호
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    • pp.89-98
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    • 2023
  • Analytical methods for detecting atranol, chloroatranol, evernic acid, (+)-usnic acid, and atranorin in sanitary napkins and mouthwashes were developed using ultrahigh performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS). UHPLC-MS/MS conditions were optimized for rapid, sensitive, and simultaneous analysis of the five allergenic compounds. The methods were validated by assessing their specificity, matrix effects, limit of detection (LOD), limit of quantification (LOQ), linearity, accuracy, and precision. Good linearity was achieved with a determination coefficient of ≥0.99. The LOD and LOQ were 2.1-9.8 and 6.4-29.6 ng/g for sanitary napkins and 0.29-0.48 and 0.87-1.45 ng/mL for mouthwashes, respectively. The accuracy and precision were within an acceptable range according to the criteria reported in the European SANTE/11813/2017 guidelines (70-120 % recovery, <20 % relative standard deviation). Therefore, these methods can be used to analyze atranol, chloroatranol, evernic acid, (+)-usnic acid, and atranorin in sanitary napkins and mouthwashes.

배전기기 전압계측 정밀도 평가시스템 개발 및 성능시험 (A Development and Performance Test of Voltage Measurement Accuracy Assessment System for Distribution Equipment)

  • 조진태;김주용;이학주;김재한
    • 조명전기설비학회논문지
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    • 제27권9호
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    • pp.83-89
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    • 2013
  • Power distribution system has been changed from radial system to closed loop or mesh system due to connection of distributed generation growth. Data from distribution equipments which are installed at distribution line is required to be accurate for the performance of DMS(Distribution Management System). This paper analyzes the voltage measurement data from distribution equipment. However, the results of the analysis are confirmed to have some errors in voltage measurement data from distribution equipment. These errors come from aging of voltage sensor in distribution equipment and inaccurate data transfer to FRTU(feeder remote terminal unit) through the controller. The main problem is that the voltage measurement data of distribution equipment can not be assessed after it's first installation at the distribution line. The voltage measurement accuracy assessment system is to assess the voltage measurement data from distribution equipment on hot-line. This study had a field test to verify the performance of system.

방송언어 개선 연구의 현황과 발전 방향 (The Current State and the Development Direction of the Studies on Improving of Broadcasting Language)

  • 조태린
    • 한국어학
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    • 제74권
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    • pp.169-197
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    • 2017
  • The purpose of this paper is to seek the development direction of the studies on improving of broadcasting language, by examining the fruits and the limitations of existing research. Firstly, this paper makes sure that the study on improving of broadcasting language is one of the subtypes of study on broadcasting language. Then the current state of the studies on improving of broadcasting language is analyzed by genre, problem, and assessment standard. According to this analysis, existing research is concentrated too much in certain genres such as current affairs and news, but also in certain problems such as accuracy or publicness infractions. Finally, this paper concludes by suggesting three development directions of the future studies on improving of broadcasting language as follows: (1) Accuracy or publicness related problems need no more studies on themselves but continuous and systematic monitoring and institutional device. (2) We need more interest and research on language used in certain genres such as TV home shopping and commercial break. (3) Fairness or soundness related problems need more studies on themselves, because the judgement or assessment standard of these problems is not only difficult to find out, but also in need of viewer and listener awareness investigation and social agreement procedure.

Diagnostic accuracy of imaging examinations for peri-implant bone defects around titanium and zirconium dioxide implants: A systematic review and meta-analysis

  • Chagas, Mariana Murai;Kobayashi-Velasco, Solange;Gimenez, Thais;Cavalcanti, Marcelo Gusmao Paraiso
    • Imaging Science in Dentistry
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    • 제51권4호
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    • pp.363-372
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    • 2021
  • Purpose: This systematic review and meta-analysis assessed the diagnostic accuracy of imaging examinations for the detection of peri-implant bone defects and compared the diagnostic accuracy between titanium (Ti) and zirconium dioxide (ZrO2) implants. Materials and Methods: Six online databases were searched, and studies were selected based on eligibility criteria. The studies included in the systematic review underwent bias and applicability assessment using the Quality Assessment of Diagnostic Accuracy Studies 2 (QUADAS-2) tool and a random-effect meta-analysis. Summary receiver operating characteristic (sROC) curves were constructed to compare the effect of methodological differences in relation to the variables of each group. Results: The search strategy yielded 719 articles. Titles and abstracts were read and 61 studies were selected for full-text reading. Among them, 24 studies were included in this systematic review. Most included studies had a low risk of bias (QUADAS-2). Cone-beam computed tomography (CBCT) presented sufficient data for quantitative analysis in ZrO2 and Ti implants. The meta-analysis revealed high levels of inconsistency in the latter group. Regarding sROC curves, the area under the curve (AUC) was larger for the overall Ti group (AUC=0.79) than for the overall ZrO2 group (AUC=0.69), but without a statistically significant difference between them. In Ti implants, the AUCs for dehiscence defects(0.73) and fenestration defects(0.87) showed a statistically significant difference. Conclusion: The diagnostic accuracy of CBCT imaging in the assessment of peri-implant bone defects was similar between Ti and ZrO2 implants, and fenestration was more accurately diagnosed than dehiscence in Ti implants.

술기 수행 평가에서 평가자의 유형별 피드백이 간호대학생의 자가 평가의 정확성, 정서반응, 자기효능감, 인지하는 피드백의 질에 미치는 효과 (Effects of Examiner's Verbal Feedback on Nursing Students' Accuracy of Self-assessment, Emotional Response, Self-efficacy, and Perceived Quality of Feedback in Skill Performance Assessment)

  • 김은정
    • 기본간호학회지
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    • 제25권2호
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    • pp.146-154
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    • 2018
  • Purpose: In this study, effects of positive, negative, and mixed verbal feedback were examined for accuracy of self-assessment, emotional responses, self-efficacy, and perceived quality of feedback in skill performance assessment. Methods: Participants were a convenience sample of 104 second-year nursing students who had completed their fundamentals of nursing class. Participants were assigned randomly to a positive, a negative or a mixed feedback group. All participants completed the performance measure and then received the assigned the type of feedback from an evaluator. After delivery of feedback, they assessed their own performance using the same sheet as the evaluator and completed the survey for emotional response, self-efficacy for learning, and quality of feedback. Results: There were no significant differences in accuracy of self-assessment and perceived quality of feedback among the three groups ($x^2=4.74$, p=.094; $x^2=3.30$, p=.192, respectively). The negative feedback group had significantly lower self-efficacy and positive emotions and more negative emotions than the other two groups (F=9.43, p=.009; $x^2=16.29$, p<.001; $x^2=5.69$, p=.005, respectively). Conclusion: Negative feedback can affect emotions and motivations for learning in nursing students and may interfere with the effectiveness of feedback, so instructors should pay more attention when providing negative feedback. Mixed feedback with an effect similar to positive feedback could be an alternative.

Statistical reference values for control performance assessment of seismic shake table testing

  • Chen, Pei-Ching;Kek, Meng-Kwee;Hu, Yu-Wei;Lai, Chin-Ta
    • Earthquakes and Structures
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    • 제15권6호
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    • pp.595-603
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    • 2018
  • Shake table testing has been regarded as one of the most effective experimental approaches to evaluate seismic response of structural systems subjected to earthquakes. However, reproducing a prescribed acceleration time history precisely over the frequency of interest is challenging because shake table test systems are eventually nonlinear by nature. In addition, interaction between the table and specimen could affect the control accuracy of shake table testing significantly. Various novel control algorithms have been proposed to improve the control accuracy of shake table testing; however, reference values for control performance assessment remain rare. In this study, reference values for control performance assessment of shake table testing are specified based on the statistical analyses of 1,209 experimental data provided by the Seismic Simulator Laboratory of National Center for Research on Earthquake Engineering in Taiwan. Three individual reference values are considered for the assessment including the root-mean-square error of the achieved acceleration time history; the percentage of the spectral acceleration that exceeds the determined tolerance range over the frequency of interest; and the error-ratio of the achieved peak ground acceleration. Quartiles of the real experimental data in terms of the three objective variables are obtained, providing users with solid and simple references to evaluate the control performance of shake table testing. Finally, a set of experimental data of a newly developed control framework implementation for uni-axial shake tables are used as an application example to demonstrate the significant improvement of control accuracy according to the reference values provided in this study.