• Title/Summary/Keyword: empirical evaluation

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A Study on Feasibility Evaluation for Prognosis Systems based on an Empirical Model in Nuclear Power Plants

  • Lee, Soo Ill
    • International Journal of Safety
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    • v.11 no.1
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    • pp.26-32
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    • 2012
  • This paper introduces a feasibility evaluation method for prognosis systems based on an empirical model in nuclear power plants. By exploiting the dynamical signature characterized by abnormal phenomena, the prognosis technique can be applied to detect the plant abnormal states prior to an unexpected plant trip. Early $operator^{\circ}{\emptyset}s$ awareness can extend available time for operation action; therefore, unexpected plant trip and time-consuming maintenance can be reduced. For the practical application in nuclear power plant, it is important not only to enhance the advantages of prognosis systems, but also to quantify the negative impact in prognosis, e.g., uncertainty. In order to apply these prognosis systems to real nuclear power plants, it is necessary to conduct a feasibility evaluation; the evaluation consists of 4 steps (: the development of an evaluation method, the development of selection criteria for the abnormal state, acquisition and signal processing, and an evaluation experiment). In this paper, we introduce the feasibility evaluation method and propose further study points for applying prognosis systems from KHNP's experiences in testing some prognosis technologies available in the market.

MEASURING THE INFLUENCE OF TASK COMPLEXITY ON HUMAN ERROR PROBABILITY: AN EMPIRICAL EVALUATION

  • Podofillini, Luca;Park, Jinkyun;Dang, Vinh N.
    • Nuclear Engineering and Technology
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    • v.45 no.2
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    • pp.151-164
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    • 2013
  • A key input for the assessment of Human Error Probabilities (HEPs) with Human Reliability Analysis (HRA) methods is the evaluation of the factors influencing the human performance (often referred to as Performance Shaping Factors, PSFs). In general, the definition of these factors and the supporting guidance are such that their evaluation involves significant subjectivity. This affects the repeatability of HRA results as well as the collection of HRA data for model construction and verification. In this context, the present paper considers the TAsk COMplexity (TACOM) measure, developed by one of the authors to quantify the complexity of procedure-guided tasks (by the operating crew of nuclear power plants in emergency situations), and evaluates its use to represent (objectively and quantitatively) task complexity issues relevant to HRA methods. In particular, TACOM scores are calculated for five Human Failure Events (HFEs) for which empirical evidence on the HEPs (albeit with large uncertainty) and influencing factors are available - from the International HRA Empirical Study. The empirical evaluation has shown promising results. The TACOM score increases as the empirical HEP of the selected HFEs increases. Except for one case, TACOM scores are well distinguished if related to different difficulty categories (e.g., "easy" vs. "somewhat difficult"), while values corresponding to tasks within the same category are very close. Despite some important limitations related to the small number of HFEs investigated and the large uncertainty in their HEPs, this paper presents one of few attempts to empirically study the effect of a performance shaping factor on the human error probability. This type of study is important to enhance the empirical basis of HRA methods, to make sure that 1) the definitions of the PSFs cover the influences important for HRA (i.e., influencing the error probability), and 2) the quantitative relationships among PSFs and error probability are adequately represented.

Application of Empirical Research Methods in Information Systems Research: Gaining Lessons Through Evaluation (경영정보학 연구에 나타난 실증적 연구방법 적용상의 문제: 평가를 통해 얻은 교훈)

  • Kang, Shin-Cheol;Lee, Zoon-Ky;Choi, Jeong-Il
    • Asia pacific journal of information systems
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    • v.16 no.2
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    • pp.1-25
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    • 2006
  • Application of appropriate research methods has assumed an important role in knowledge accumulation endeavors in the scientific research community. The current study reported here summarizes how we used the empirical methods in IS research, what we need to improve in using empirical study as research methodology through the set of comprehensive research guideline. From the survey and review of seminal and classical research guidelines, we developed our own 28 checklist for research design, statistical analysis, and conclusion, which can be commonly applied to all articles that employ inferential statistical methods in IS research. Then, we critically evaluated the usage of empirical research methods in major IS journals by using the checklist, with the goal of improving the quality of academic papers. In this study, we scrutinized four major IS journals which published empirical papers from 1991 to 2000: MIS Quarterly, Journal of MIS, Information Systems Research, and Decision Sciences. As a result of intensive evaluation work, we could highlight many areas that are lagging and call for greater attention with regard to the proper usage of empirical study in IS research. The research findings in this study can be referred as checklist and guideline when IS researcher applies the empirical method.

An Study on the Impact of N/A Check Item on the Security Level Result through Empirical Verification (실증검증을 통한 N/A 점검항목이 보안 수준 결과에 미치는 영향에 관한 연구)

  • Lee, Jun Ho;Sung, Kyung Sang;Oh, Hea Seok
    • KIPS Transactions on Computer and Communication Systems
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    • v.3 no.8
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    • pp.271-276
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    • 2014
  • This study analyzed that N/A check items affect the results of the security level degree, when performing vulnerability analysis evaluation. For this, we were used vulnerability analysis evaluation range, check items and quantitative calculation method. Furthermore, were applied grade and weight for the importance of the items. In addition, because technology develop rapidly, the institution is always exposed risk. therefore, this study was carried out empirical analysis by applying RAL(Risk Acceptabel Level). According to the analyzed result N/A check items factors affecting the level of security has been proven. In other words, this study found that we shall exclude inspection items irrelevant to the institution characteristics, when perform vulnerability analysis evaluation. In this study suggested that security level evaluation shall performed, after that exclude items irrelevant to the institution characteristics based on empirical verification. And also, it proposed that model research is required for establish check items for which analysis-evaluate vulnerability based on empirical verification.

Review on Library Science Research Evaluation in Korea (문헌정보학분야의 논문평가에 관한 고찰)

  • Lee Seung-Chae
    • Journal of Korean Library and Information Science Society
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    • v.36 no.4
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    • pp.199-210
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    • 2005
  • This study reviews the research papers which deal with research evaluation in library science and discusses on quantitative and qualitative research methods, and non-empirical research. For the purpose of improving paper production system, encouragement of publishing review paper and review Journal Is recommended.

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An Empirical Comparative Analysis Between Kano and Improved Kano Methods (Kano 품질속성 평가방법론들의 실증적 비교분석)

  • Yoon, Jae-Wook;Lee, Hee-Young
    • Journal of Korean Society for Quality Management
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    • v.37 no.4
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    • pp.31-42
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    • 2009
  • Various studies have been undertaken in order to effectively understand customer requirements. Kano proposed a dualistic approach, physical fulfillment and customer satisfaction, to differentiate Attractive, Must-be, One-dimensional quality attributes. As there were a few limitations on the Kano's method, researchers have proposed improved methods. However, there have been few empirical evidences that the improved methods are superior to the original Kano's method for identifying relevant quality attributes. The objective of this study is to provide a comparative study on Kano and improved Kanomethods based on empirical analysis of quality attributes on University services. For the analysis of the questionnaire formats, the Kano's original 5 scale questionnaire is more effective than improved methods, direct and 3 scale questionnaire. For the analysis of evaluation methods, the original Kano and Timko's method using the evaluation table are more effective than quantifying methods, Domouchel and Lim's methods.

Evaluation and Application of Prediction Models for the Daylight Performance of a Light-Pipe System (광파이프 시스템의 채광성능 예측모델의 검증 및 적용)

  • Yun, Geun Young;Shin, Ju Young;Kim, Jeong Tai
    • KIEAE Journal
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    • v.10 no.1
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    • pp.65-72
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    • 2010
  • The use of natural light has the potential for improving both the energy efficiency and indoor environmental quality in buildings. A light-pipe system can introduce daylight to spaces that would otherwise not be able to benefit from the advantages of daylight penetration. For the light-pipe system to be widely used in Korea, it is important to quantify its daylighting performance with due consideration regarding the effects imposed by the local climate conditions. This paper presents the evaluation results of existing semi-empirical models to predict daylighting performance of a light-pipe system. The evaluation of the existing models was based on the monitoring data obtained from a underground parking lot in which the light-pipe system was installed. Comparisons were made between the predicted and the monitored data obtained from the study. The results indicated that semi-empirical models which was developed using the experimental data obtained under the Korean climatic conditions had a good prediction performance. We also quantified the effects caused by sky conditions, solar altitudes, room dimensions, and the aspect ratio of a light-pipe system on both the daylighting performance of the light-pipe system and the indoor illuminance distributions of the space using the semi-empirical model. Finally, this paper provides the design guideline of the light-pipe system for its application to an underground parking lot space.

An Empirical Study on Development of IS Evaluation Indices : In Case of Public Sectors (정보시스템 평가지표 개발에 관한 실증적 연구 : 공공부문을 중심으로)

  • 정해용;김상훈
    • Journal of the Korean Operations Research and Management Science Society
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    • v.28 no.4
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    • pp.155-189
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    • 2003
  • In this research, the comprehensive evaluation model of IS(information systems) for public sectors is theoretically constructed through reviewing and integrating previous IS evaluation-related research. This model is hypothesized to consist of five sectors(System Sector, User Sector, Organization and Management Sector, Resource Management Sector and Strategic Contribution Sector), ten evaluation items belonging to these five evaluation sectors, and sixty two evaluation indices for these ten evaluation items. The results of empirical analyses to test the validity of the research model show that the evaluation sectors turn out to be the same ones as proposed in the hypothetical model. The evaluation items(System Quality, Information Quality, Service Quality) in System Sector proves to be consistent with the hypothetical model. However, in case of User Sector, two evaluation items(Perceived Usefulness and User Satisfaction) which are included in the hypothetical model are found to be merged into one item(User Satisfaction). And, it is shown that four evaluation items such as the Efficiency of Internal Process, Customer Satisfaction, Organizational Innovation, and the Degree of Informatization competence improvement are included in Organization and Management Sector, differently from the research model in which the items, Organizational innovation and the Degree of Informatization competence improvement, are not divided. As a final result, sixty two evaluation indices that comprise all the evaluation items belonging to five sectors are found to be reduced to fifty seven ones through factor analyses, criterion-related validity tests and reliability analyses.

A Study on Evaluation Method of Cable Tension for Railway Steel Composite Bridge (강철도 복합교량 케이블의 장력 평가기법에 관한 연구)

  • Choi, Jung-Youl;Lee, Soo-Jae;Chung, Jee-Seung
    • The Journal of the Convergence on Culture Technology
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    • v.8 no.4
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    • pp.407-413
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    • 2022
  • In this study, the empirical formula for evaluating cable tension based on long-term measurement for about 3 years according to temperature change was proposed by proving the correlation between the expansion joint displacement of the upper road bridge and the cable tension of the lower railway bridge. The tension prediction results using the empirical formula for tension evaluation each cables proposed in this study were found to be in good agreement with the cable tension using the vibration method within 3%. Therefore, it was analyzed that it could be applied together with the vibration method that was an experimental technique, to predict and evaluate the cable tension in serviced railway steel composite bridge. As a result of applying the estimated temperature calculated by the empirical formula for expansion proposed in this study to the empirical formula, it was analyzed that a high level of reliability could be secured when compared with the vibration method. Therefore, it is judged that the empirical formula for cable tension evaluation reflecting the estimated temperature proposed in this study can be used to predict the tension of cables according to climate change in the future and establish a maintenance plan.

A Study on the Empirical Evaluation of Quality Factor on Library Service for the Disabled (도서관장애인서비스 품질요인의 실증적 평가에 대한 연구)

  • Bae, Kyung-Jae
    • Journal of the Korean Society for Library and Information Science
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    • v.50 no.2
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    • pp.271-287
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    • 2016
  • This study intends to review the quality factors of library service for the disabled using user-centered approach. For the empirical review of quality factors, Nine quality factors were drawn after analyzing the current library service quality factors and the standards of library service for the disabled. Using these factors, The survey for identifying importance of factors and the qualitative evaluation of service cases were performed in this study. As a result of this survey, the most critical but relatively weak quality factors were facility, collection and staff factors. And the qualitative evaluation results of service cases indicated that the reading culture program and the information service factors were critical.