• Title/Summary/Keyword: Data uncertainty

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Shape Optimization of Electric Machine Considering Uncertainty of Design Variable by Stochastic Finite Element Method (확률유한요소법을 이용한 설계변수의 불확실성을 고려한 전기기기의 형상최적설계)

  • Hur, Jin;Hong, Jung-Pyo
    • The Transactions of the Korean Institute of Electrical Engineers B
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    • v.49 no.4
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    • pp.219-225
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    • 2000
  • This paper presents the shape optimization considering the uncertainty of design variable to find robust optimal solution that has insensitive performance to its change of design variable. Stochastic finite element method (SFEM) is used to treat input data as stochastic variables. It is method that the potential values are series form for the expectation and small variation. Using correlation function of their variables, the statistics of output obtained form the input data distributed. From this, design considering uncertainty of design variables.

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Impacts of Uncertainty of Water Quality Data on Wate Quality Management (수질자료의 불확실성이 수질관리에 미치는 영향)

  • Kim, Geonha
    • Journal of Korean Society on Water Environment
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    • v.22 no.3
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    • pp.427-430
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    • 2006
  • Uncertainty is one of the key issues of the water quality management. Uncertainty occurs in the course of all water quality management stages including monitoring, modeling, and regulation enforcement. To reduce uncertainties of water quality monitoring, manualized monitoring methodology should be developed and implemented. In addition, long-term monitoring is essential for acquiring reliable water quality data which enables best water quality management. For the water quality management in the watershed scale, fate of pollutant including its generation, transport and impact should be considered while regarding each stage of water quality management as an unit process. Uncertainties of each stage of water quality management should be treated properly to prevent error propagation transferred to the next stage of management for successful achievement of water quality conservation.

Prediction of unmeasured mode shapes and structural damage detection using least squares support vector machine

  • Kourehli, Seyed Sina
    • Structural Monitoring and Maintenance
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    • v.5 no.3
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    • pp.379-390
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    • 2018
  • In this paper, a novel and effective damage diagnosis algorithm is proposed to detect and estimate damage using two stages least squares support vector machine (LS-SVM) and limited number of attached sensors on structures. In the first stage, LS-SVM1 is used to predict the unmeasured mode shapes data based on limited measured modal data and in the second stage, LS-SVM2 is used to predicting the damage location and severity using the complete modal data from the first-stage LS-SVM1. The presented methods are applied to a three story irregular frame and cantilever plate. To investigate the noise effects and modeling errors, two uncertainty levels have been considered. Moreover, the performance of the proposed methods has been verified through using experimental modal data of a mass-stiffness system. The obtained damage identification results show the suitable performance of the proposed damage identification method for structures in spite of different uncertainty levels.

PROPAGATION OF NUCLEAR DATA UNCERTAINTIES FOR PWR CORE ANALYSIS

  • Cabellos, O.;Castro, E.;Ahnert, C.;Holgado, C.
    • Nuclear Engineering and Technology
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    • v.46 no.3
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    • pp.299-312
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    • 2014
  • An uncertainty propagation methodology based on the Monte Carlo method is applied to PWR nuclear design analysis to assess the impact of nuclear data uncertainties. The importance of the nuclear data uncertainties for $^{235,238}U$, $^{239}Pu$, and the thermal scattering library for hydrogen in water is analyzed. This uncertainty analysis is compared with the design and acceptance criteria to assure the adequacy of bounding estimates in safety margins.

RESONANCE SELF-SHIELDING EFFECT IN UNCERTAINTY QUANTIFICATION OF FISSION REACTOR NEUTRONICS PARAMETERS

  • Chiba, Go;Tsuji, Masashi;Narabayashi, Tadashi
    • Nuclear Engineering and Technology
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    • v.46 no.3
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    • pp.281-290
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    • 2014
  • In order to properly quantify fission reactor neutronics parameter uncertainties, we have to use covariance data and sensitivity profiles consistently. In the present paper, we establish two consistent methodologies for uncertainty quantification: a self-shielded cross section-based consistent methodology and an infinitely-diluted cross section-based consistent methodology. With these methodologies and the covariance data of uranium-238 nuclear data given in JENDL-3.3, we quantify uncertainties of infinite neutron multiplication factors of light water reactor and fast reactor fuel cells. While an inconsistent methodology gives results which depend on the energy group structure of neutron flux and neutron-nuclide reaction cross section representation, both the consistent methodologies give fair results with no such dependences.

Effects of uncertainty and spousal support on infertility-related quality of life in women undergoing assisted reproductive technologies (보조생식술을 받는 여성의 불확실성과 배우자 지지가 난임 관련 삶의 질에 미치는 영향)

  • Lee, Hye Shin;Boo, Sunjoo;Ahn, Jeong-Ah;Song, Ju-Eun
    • Women's Health Nursing
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    • v.26 no.1
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    • pp.72-83
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    • 2020
  • Purpose: The purpose of this study was to investigate the effects of uncertainty and spousal support on infertility-related quality of life (QoL) in women undergoing assisted reproductive technologies. Methods: In this correlational survey study, 172 infertile women undergoing assisted reproductive technologies for infertility treatment at M hospital in Seoul participated. Data collection took place at the outpatient department of M hospital using a self-report questionnaire from July to August 2019. Data were analyzed using SPSS for Windows version 28.0. Results: The mean scores for uncertainty, spousal support, and infertility-related QoL were 28.35 (out of 50), 86.67 (out of 115), and 57.98 (out of 100), respectively. Infertility-related QoL was positively correlated with spousal support and negatively correlated with uncertainty. According to the regression analysis, infertility-related QoL was significantly affected by uncertainty, total number of assisted reproductive technology treatments, marriage duration, subjective health status, the financial burden of infertility testing, and the presence of a burdensome person. These variables had an explanatory power of 35.0% for infertility-related QoL. Conclusion: Uncertainty was an important factor influencing infertility-related QoL among women undergoing assisted reproductive technologies. It is necessary to develop and implement a nursing intervention program focused on reducing various forms of uncertainty during assisted reproductive procedures and to consider other factors affecting infertility-related QoL in the clinical setting.

Perceived Anxiety and Uncertainty in Hematopoietic Stem Cell Transplantation Recipients to and from Isolation Unit (격리병동 입.퇴실시 조혈모세포 이식 환자가 지각하는 불안과 불확실성)

  • Kim, Hye-Jo;Choi, Dong-Won;Park, Ho-Ran;Sohng, Kyeong-Yae
    • Journal of Korean Academy of Fundamentals of Nursing
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    • v.13 no.3
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    • pp.428-436
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    • 2006
  • Purpose: To investigate the levels of uncertainty and anxiety at admission and discharge to the isolation unit for patients undergoing hematopoietic stem cell transplantation (HSCT). Method: The data were collected from 60 patients who were admitted to the department of HSCT. Uncertainty and anxiety were assessed using the Mishel Uncertainty in Illness Scale (MUIS) and Anxiety Inventory (STAI). Collected data were analyzed using the SAS program. Results: The mean score for anxiety at admission was 2.20, and at discharge 2.10. The mean score for uncertainty at admission was 2.19, and at discharge 2.07. The anxiety at admission the group with physical discomfort was higher than that of group without physical discomfort. A positive relationship was found between anxiety and uncertainty at admission and at discharge. The major variables were expectation for cure and physical discomfort, explaining 25.87% of the anxiety at admission. The major variable was expectation for cure, explaining 20.94% of the uncertainty at admission. Conclusion: Front the above results, it can be concluded that support and consideration are required to reduce anxiety of the inpatient in single room.

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The Precautionary Behavior of Korean Households under Health Uncertainty

  • Kong, Moon-Kee;Lee, Hoe-Kyung
    • Proceedings of the Korea Inteligent Information System Society Conference
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    • 2001.01a
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    • pp.325-329
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    • 2001
  • This paper tests existence of precautionary saving motive under health uncertainty, using household level panel data from Korea. For this purpose, this paper considers a dynamic health capital model with health uncertainty and derives testable equations for changes in consumption and medical expenditures. Under this framework, households who face future health uncertainty will exhibit precautionary behavior by depressing consumption or increasing investment in health. To test this hypothesis, the paper uses the conditional variance of health as the direct measure of health uncertainty, obtained by estimating a multinomial logit model. Empirical results using the Korean Household Panel Study (KHPS, 1993 - 1997) suggest that Korean elderly households follow the precautionary behavior to insure against future health risk.

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The Contribution of Competence in Parenting: Uncertainty related Children's Diseases, and Nursing Educational Need (입원 환아 어머니의 부모 역할 효능감 영향 요인: 질병에 대한 불확실성, 간호 교육 요구도)

  • Nam, Hyun A;Lee, Hwa Jin;Kim, Mi Ok
    • Korean Parent-Child Health Journal
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    • v.17 no.1
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    • pp.29-36
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    • 2014
  • Purpose: Competence in parenting helps the parent to recognize the ability to resolve problems arising to children, allowing positive interactions with children through desirable child-rasing behavior and smooth communication with children. This study aims to identify the contribution of uncertainty and educational needs to the competence in parenting. Methods: Total 159 mothers responded a questionnaire developed to measure uncertainty, educational needs, and competence in parenting. t-test, ANOVA, and stepwise multiple regression with the SPSS program were used to analyze the data. Results: We found that uncertainty, nursing educational need, and mothers' age had influence to the competence in parenting. Conclusion: Nursing interventions provided to the mothers of hospitalized children for better parental competence need to include programs for alleviating uncertainty and satisfying the need for nursing education.

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An Analysis of the Influence of Knowledge Management Factors on Knowledge Transfer (지식이전에 대한 지식경영 요인의 영향 분석)

  • Oh Jay-In
    • The Journal of Information Systems
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    • v.15 no.1
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    • pp.191-213
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    • 2006
  • The purpose of this research is to identify the structure among determining factors focusing on knowledge transfer and analyze and prove the causal relation on knowledge transfer in Korean companies and public corporations. The results from the analysis of data collected in this study are as follows. First, forum among organization related factors has the positive relation with uncertainty in a significant level. Second, the higher the knowledge presentation and the ease of use are among information systems related factors, the lower the ambiguity and uncertainty are. Third, among process related factors, unification has the negative relation with ambiguity and uncertainty in a significant level. Fourth, a better manpower employment contributes to a worse ambiguity and uncertainty. Fifth, ambiguity has a negative relation with knowledge transfer. In conclusion, the factors that lower the ambiguity and facilitate knowledge transfer include information systems, unification, and manpower employment. These factors, however, influence on uncertainty, which turns out to be nothing to do with knowledge transfer.

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