• Title/Summary/Keyword: data uncertainty

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Application of Rainfall Runoff Model with Rainfall Uncertainty (강우자료의 불확실성을 고려한 강우 유출 모형의 적용)

  • Lee, Hyo-Sang;Jeon, Min-Woo;Balin, Daniela;Rode, Michael
    • Journal of Korea Water Resources Association
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    • v.42 no.10
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    • pp.773-783
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    • 2009
  • The effects of rainfall input uncertainty on predictions of stream flow are studied based extended GLUE (Generalized Likelihood Uncertainty Estimation) approach. The uncertainty in the rainfall data is implemented by systematic/non-systematic rainfall measurement analysis in Weida catchment, Germany. PDM (Probability Distribution Model) rainfall runoff model is selected for hydrological representation of the catchment. Using general correction procedure and DUE(Data Uncertainty Engine), feasible rainfall time series are generated. These series are applied to PDM in MC(Monte Carlo) and GLUE method; Posterior distributions of the model parameters are examined and behavioural model parameters are selected for simplified GLUE prediction of stream flow. All predictions are combined to develop ensemble prediction and 90 percentile of ensemble prediction, which are used to show the effects of uncertainty sources of input data and model parameters. The results show acceptable performances in all flow regime, except underestimation of the peak flows. These results are not definite proof of the effects of rainfall uncertainty on parameter estimation; however, extended GLUE approach in this study is a potential method which can include major uncertainty in the rainfall-runoff modelling.

The Relationships among Uncertainty, Appraisal of Uncertainty, Depression, Anxiety and Perceived Health Status in Patients with Atrial Fibrillation (심방세동 환자의 불확실감, 불확실감의 평가, 우울, 불안, 주관적 건강지각 간의 관계)

  • Kang, Younhee
    • Korean Journal of Adult Nursing
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    • v.17 no.2
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    • pp.230-238
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    • 2005
  • Purpose: The purposes of this study were to explore the concept of uncertainty and to examine the relationships among uncertainty, appraisal of uncertainty, depression, anxiety, and perceived health status in patients with atrial fibrillation. Method: The study utilized a descriptive correlational survey design using a face to face interview method. A convenience sample of 49 subjects were recruited from K university hospital over 8 months. The data were analyzed by t-test, ANOVA, Pearson correlation and partial correlation analysis. Results: 1) Subjects perceived with moderately high uncertainty(M=65.98); moderate physical health(M=39.80), mental health(M=47.38), and general health(M=2.94); moderate anxiety(M= 44.78); and slightly low depression(M=15.33). 2) There were significant differences in uncertainty by gender and education. 3) Uncertainty and danger appraisal were significantly correlated(r=.32, p=.03) while the uncertainty was not associated with opportunity appraisal. 4) Uncertainty was significantly correlated with mental health(r=-.31, p=.04), anxiety(r=.38, p=.01), and depression(r=.37, p=.01). Conclusion: This study was the first trial to explore uncertainty and to examine the relationships among its associated factors in Korean patients with atrial fibrillation. Thus, based on the findings of this study, directions for nursing practice and further nursing research for patients with atrial fibrillation were suggested.

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A Study on Factors Influencing the Appraisal of Uncertainty in Patients having Rheumatoid Arthritis (류마티스 관절염 환자의 불확실성 인지에 영향을 주는 요인 탐색)

  • Yoo, Kyoung-Hee
    • Journal of muscle and joint health
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    • v.4 no.2
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    • pp.277-296
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    • 1997
  • This study was conducted to investigate the influencing factors on the appraisal of uncertainty in patients having rheumatoid arthritis. Subjects of the study constituted 528 patients who visited outpatient clinics of two university hospitals and one general hospital in Seoul. Self report questionnaires were used to measure the variables influencing the appraisal of uncertainty. Reliability coefficients of these instruments were found Cronbach's Alpha=$.70{\sim}.96$. In data analysis, SPSS PC 6.0 program was utilized for descriptive statistics, Pearson's correlation, logistic and multiple regression analysis. The results of logistic and multiple regression analysis were as follows 1) Among the independent variables, significant factors to explain the appraisal of uncertainty in patients were uncertainty(p<.001), severity of illness(p<.05), educational level (p<.05) and age (p<.05). 2) When patients appraised uncertainty as "Danger", significant factors to explain the appraisal of uncertainty were uncertainty(p<.0001), age(p<.0005), severity of illness(p<.001), educational level (p<.05). 3) When patients appraised uncertainty as "Opportunity", significant factors to predict the appraisal of uncertainty were uncertainty(p<.0005), social support(p<.0005), severity of illness(p<.005), credible authority(p<.05), age(p<.05) and educational level (p<.05).

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Assessment on shock pressure acquisition from underwater explosion using uncertainty of measurement

  • Moon, Seok-Jun;Kwon, Jeong-Il;Park, Jin-Woo;Chung, Jung-Hoon
    • International Journal of Naval Architecture and Ocean Engineering
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    • v.9 no.6
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    • pp.589-597
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    • 2017
  • This study aims to verify experimentally the specifications of the data acquisition system required for the precise measurement of signals in an underwater explosion (UNDEX) experiment. The three data acquisition systems with different specifications are applied to compare their precision relatively on maximum shock pressures from UNDEX. In addition, a method of assessing the acquired signals is suggested by introducing the concept of measurement uncertainty. The underwater explosion experiments are repeated five times under same conditions, and assessment is conducted on maximum quantities acquired from underwater pressure sensors. It is confirmed that the concept of measurement uncertainty is very useful method in accrediting the measurement results of UNDEX experiments.

A Study on Robust Identification Based on the Validation Evaluation of Model (모델의 타당성 평가에 기초한 로바스트 동정에 관한 연구)

  • Lee, Dong-Cheol;Chung, Hyung-Hwan;Bae, Jong-Il
    • Proceedings of the KIEE Conference
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    • 2000.07d
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    • pp.2690-2692
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    • 2000
  • In order to design a stable robust controller, nominal model, and the upper bound about the uncertainty which is the error of the model are needed. The problem to estimate the nominal model of controlled system and the upper bound of uncertainty at the same time is called robust identifcation. When the nominal model of controlled system and the upper bound of uncertainty in relation to robust identifcation are given, the evaluation of the validity of the model and the upper bound makes it possible to distinguish whether there is a model which explains observation data including disturbance among the model set. This paper suggests a method to identify the uncertainty which removes disturbance and expounds observation data by giving a probable postulation and plural data set to disturbance. It also examines the suggested method through a numerical computation simulation and validates its effectiveness.

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A Study on Uncertainty, Anxiety and Nursing Needs in Mothers of Hospitalized Children (입원 아동 어머니가 지각하는 불확실성과 불안 및 간호요구도)

  • Yoo, Kyung-Hee
    • Journal of Korean Academy of Fundamentals of Nursing
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    • v.14 no.2
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    • pp.213-220
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    • 2007
  • Purpose: This study was conducted to investigate uncertainty, anxiety and nursing needs in mothers of hospitalized children. Method: Self report questionnaires were used to measure the variables. Variables were uncertainty, anxiety and nursing needs. In data analysis, SPSSWIN 12.0 program was utilized for descriptive statistics, Pearson's correlation coefficients, and regression analysis. Results: Cronbach's alphas of .84 to .97 indicate reliability of the instruments. Uncertainty positively correlated with anxiety (r=.624, p<.001) and nursing needs (r=.147, p<.05), and anxiety positively correlated with nursing needs (r=.262, p<.01). In regression analysis of anxiety, uncertainty, nursing assessment of nursing needs and duration of hospitalization were significant predictors, explaining 45.1% of variance. Conclusion: Uncertainty was a significant predictor of anxiety in mothers whose children were hospitalized. Therefore, nursing interventions which decrease uncertainty must be developed for these mothers.

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Uncertainty Analysis of Hyung San River Discharge due to the methods of Discharge Measurement (유량측정방법에 따른 형산강유량의 불확실도 분석)

  • Seo, Kyu-Woo;Kim, Su-Hyun;Kim, Dai-Gon
    • Proceedings of the Korea Water Resources Association Conference
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    • 2005.05b
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    • pp.1538-1542
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    • 2005
  • This study is to secure more accurate data of the discharge on the measurement by gaining a reliable hydrological data through the comparison the present method of measuring them and the other way that is based ISO. This study suggests the applicable measurement method of the discharge that has reliance through general elements and the analysis of uncertainty by comparing and assaying the data of the Hyung San River that is measured by the present standard. The result of this study makes us realize that we should complement the measurement method of the discharge securing the reliable and accurate hydrological data Hydrological data is very important things to perform domestic river works or install some structure in river or coast. Securing reliable and accurate hydro-data and making a thesis should go on in other to do any construction in river or coast.

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Probabilistic Interpretation of NDE Data in Condition Assessment of Bridge Element (교량안전진단에 있어서 비파괴 시험자료의 통계적 해석 방법)

  • 심형섭;강보순;황성춘
    • Proceedings of the Korea Concrete Institute Conference
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    • 2001.11a
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    • pp.803-808
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    • 2001
  • Mathematical basis of interpretation of data from nondestructive evaluation (NDE) methods in bridge inspection is presented. In bridge inspection with NDE methods, NDE data are not assessments. NDE data must be interpreted as condition of element. Interpretation is then assessment. Correct assessments of conditions of bridge elements depend on the accuracy and variability in test data as well as on the uncertainty of correlations between attributes (what is measured) and conditions (what is sought in the inspection). Inaccuracy and variability in test data defines the qualify or NDE test. The qualify or test itself is important, but in view of condition assessment, the significance of uncertainty in correlations of attributes and conditions must be combined. NDE methods that are accurate in their measurements may still be found to be poor methods if attributes are uncertain indicators of condition of bridge elements. This paper reports mathematical presentation of inaccuracy and variability in test data and of uncertainty in correlation of attributes to element conditions with three examples of NDE methods.

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The Uncertainty, Regret Experience, and Negative Behavior Intention of Fashion Consumers According to the Types of Internet Shopping Malls (인터넷 쇼핑몰 유형별 패션 소비자의 불확실성, 후회경험 및 부정적 행동의도에 관한 연구)

  • Lee, Eun-Jin;Jung, Wook-Whan
    • Fashion & Textile Research Journal
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    • v.15 no.5
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    • pp.763-776
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    • 2013
  • This study investigated the uncertainty, regret experience, and negative behavior intention of fashion consumers according to the types of internet shopping malls. The data was obtained from internet fashion consumers, and 394 responses were used in the data analysis. The statistical analysis methods were frequency analysis, factor analysis, reliability analysis, t-test, ANOVA, and regression analysis. As results, the uncertainty of internet fashion consumers was composed of two factors; information uncertainty and preference uncertainty. The regret experience was composed of function or service regret, suitability regret, and product regret. Also, the negative behavior intention was composed of purchase switching intention and purchase deferral intention. The information uncertainty of fashion consumers positively affected the negative behavior intention in all types of internet shopping malls (e.g., open market, integrated shopping mall, and fashion specialized shopping mall). In open market, the preference uncertainty negatively affected the purchase switching intention; however, the preference uncertainty positively affected the purchase deferral intention. In open market and fashion specialized shopping mall, the product regret of internet fashion consumers positively affected the negative behavior intention. In addition, there were partially significant differences in the factors of uncertainty, regret experience, and negative behavior intention by gender and marital status of demographic characteristics. The results of this study will provide useful information to the marketing strategies considering fashion consumer's negative emotion and behaviors according to the types of internet shopping malls.

Economic Policy Uncertainty and Korean Economy : Focusing on Distribution Industry Stock Market

  • Jeon, Ji-Hong;Lee, Hyun-Ho;Lee, Chang-Min
    • Journal of Distribution Science
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    • v.15 no.12
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    • pp.41-51
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    • 2017
  • Purpose - This study proposes the impact of the US and Korean economic policy uncertainty on macroeconomy, and its effect on Korea. The economic policy uncertainty index of the US and Korea is used to represent the economic policy uncertainty on Korean economy. Research design, data, and methodology - In this paper, we collect the eight variables to find out the interrelationship among the US and Korean economic policy uncertainty index of the US and macroeconomic indicators during 1990 to 2016, and use Vector Error Correction Model. Result - The distribution industry stock index in Korea is influenced by the economic policy uncertainty index of the US rather than of Korea. All variables are related negatively to the economic policy uncertainty index of the US and Korea from Vector Error Correction Model. This study shows that the economic policy uncertainty index of the US and Korea has the dynamic relationships on the Korean economy. Conclusions - A higher economic policy uncertainty shows a greater economy recession of a country. Finally, the economic policy uncertainty of the Korea has an intensive impact on Korea economy. Particularly, the economic policy uncertainty of the US has a strong impact on distribution industry stock market in Korea.