• Journal of the Institute of Electronics Engineers of Korea TE
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• v.39 no.4
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• pp.370-378
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• 2002

Fuzzy inference which combines numerical data and linguistic data has been used to design adaptive filter algorithms. In adaptive IIR filter design, the fuzzy prefilter is taken account, and applied to both direct and lattice structure. As for the fuzzy inference of the fuzzy filter, the Sugeno's method is employed. As membership functions and inference rules are recursively generated through neural network, the accuracy can be improved. The proposed adaptive algorithm, adaptive IIR filter with fuzzy prefilter, has been applied to adaptive system identification for the purposed of performance test. The evaluations have been carried out with viewpoints of convergence property and tracking properties of the parameter estimation. As a result, the faster convergence and the better coefficients tracking performance than those of the conventional algorithm are shown in case of direct structures.

• Journal of muscle and joint health
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• v.26 no.3
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• pp.214-222
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• 2019

Purpose: The purpose of this study was to examine the mediating effects of self-esteem and meaning of life in the relationship between stress and depression in adults. Methods: The subjects of this study were 162 adults aged 19 to 64 who live in Jeollabuk-do and capital area. Data were collected from March to April 2018. The data were analyzed by independent t-test and one way ANOVA analysis. The mediating effects were verified by the Bootstrapping method using the PROCESS macro for SPSS. Results: The results showed that stress had a direct effect on self-esteem and depression, self-esteem had a direct effect on depression. Self-esteem had a mediating effect on the relationship between stress and depression. However, the meaning of life did not have any direct or mediating effects on depression. Conclusion: In order to reduce depression in adults, strategies for improving self-esteem are needed along with stress management. As for the effect of life meaning on depression, it is necessary to measure and apply the meaning of multidimensional life repeatedly.

• Nuclear Engineering and Technology
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• v.44 no.7
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• pp.709-718
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• 2012

The pressurized water reactor APR1400 adopts DVI (Direct Vessel Injection) for the emergency cooling water in the upper downcomer annulus. The International Standard Problem number 50 (ISP-50) was launched with the aim to investigate thermal hydraulic phenomena during a 50% DVI line break scenario with best estimate codes making use of the experimental data available from the ATLAS facility located at KAERI. The present work describes the calculation results obtained for the ISP-50 using the RELAP5/MOD3.3 system code. The work aims at validation and assessment of the code to reproduce the observed phenomena and investigate about its limitations to predict complicated mixing phenomena between the subcooled emergency cooling water and the two-phase flow in the downcomer. The obtained results show that the overall trends of the main test variables are well reproduced by the calculations. In particular, the pressure in the primary system show excellent agreement with the experiment. The loop seal clearance phenomenon was observed in the calculation and it was found to have an important influence on the transient progression. Moreover, the collapsed water levels in the core are accurately reproduced in the simulations. However, the drop in the downcomer level before the activation of the DVI from safety injection tanks was underestimated due to multi-dimensional phenomena in the downcomer that are not properly captured by one-dimensional simulations.

• Journal of Korean Society of Water and Wastewater
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• v.25 no.3
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• pp.325-334
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• 2011

Market Environment around water work industry is rapidly changing. ISO, International Organization for Standardization, announced the international water work service standard for comparison and evaluation between nations and businesses. And developed countries in water work are introducing market principle for growth of nation's water industry and reinforcement of its competitiveness. Also, some local governments entrusted their water utilities for improvement of competitiveness of water work. However, as some failure cases from overseas came out with emphasis, there are many refuting perspective about entrusted operation achievements of domestic water market. Hence, this paper evaluated competitiveness of domestic local water utilities from the perspective of productivity. After evaluating productivity using Malmquist productivity index, the authors compared and analyzed whether there is a difference of productivity between two different operating types by using Mann-Whitney test. As a result of analysis, it has shown that local water utilities achieved higher productivity at entrusted operation type rather than direct operation type. The local water utilities which chose entrusted operation had increased the productivity 13.9% on total factor productivity(TFP) during experimenting period, while the local water utilities which chose direct operation had increased 0.2%. The background of achieving this high productivity in entrusted operation was analyzed as a result of the higher technological effectiveness of a special water company. The result of this study can be referred when local government needs to decide on what operating types they will use.

• The Korean Journal of Food And Nutrition
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• v.23 no.1
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• pp.15-22
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• 2010

This study was conducted to evaluate the antioxidative effect and antimutagenic capacity of ethanol extracts of Flammulina velutipes by employing biological and biochemical assays. The $IC_{50}$ of MDA with BSA conjugation reaction, lipid peroxidation and scavenging effect on DPPH radical in ethanol extracts of Flammulina velutipes was found to be 28.39 mg/assay, 9.33 mg/assay and 144.61 mg/assay respectively. Therefore, the most effective antioxidative capacity of ethanol extracts of Flammulina velutipes was $Fe^+$-induced linoleate peroxidation, among the method used this study. The indirect and direct antimutagenic effects of the ethanol extracts of Flammulina velutipes were examined by the Ames test using Salmonella typimurium TA98 and TA100. The inhibition rates on indirect mutagenicity mediated by 2-anthramine and on direct mutagenicity mediated by sodium azide in Salmonella typimurium TA100 and mediated by 2-nitrofluorene in Salmonella typimurium TA98 were 0%, respectively. These findings indicate that ethanol extracts of Flammulina velutipes have no effects on indirect and direct mutagenicity. Based on these results, it believed that the ethanol extracts of Flammulina velutipes has antioxidative capacities, and is a the candidate for the prevention and dietetic treatment of chronic diseases and the development of antioxidative functional food.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2003.11a
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• pp.99-102
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• 2003

The different methods such as HPLC, indirect- and direct-ELISA were employed for the analysis of microtoxins and the results of each method were compared in terms of the detection limit and accurary. Three toxins, microcystin-RR, -LR and -YR were clearly separated by HPLC using 0.05 M methanol and phosphate buffer used as a solvent system. The calibration curves for the toxins were linear in the range of 5 ng to 50 ng. The standard curves for the immunoassay of microcystin obtained by direct and indirect ELISA are compared. The linear responses of inhibitions of binding by microcystin in the direct and indirect competitive ELISA were in the range of 10 ng to 1000 ng and 50 pg to 160 pg, respectively. Distribution of microtoxins at 11 sites in the Nakdong river and several lakes in Korea was also studied. The most dominant microcystin variant in the test sites was found to be microcystin-RR.

• Korean Journal of Adult Nursing
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• v.24 no.2
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• pp.119-129
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• 2012

Purpose: The purpose of this study was to test hand hygiene behavior model of hospital nurses, based on theory of planned behavior. Methods: Data were collected from 253 nurses from four university hospitals for the period of December 2010 to January 2011. Data were analyzed using of SAS (ver.9.1). Fitness of the study model was identified with SAS PROC CALIS. Results: The overall fitness was $x^2$=57.81 (df=13, $p$ <.001), GFI=.99, AGFI=.99, CFI=.95, NFI=.93. The variance of actual implementation of hand hygiene by predictor variables was 11.0% and the variance of intention to hand hygiene was 53.5%. Variable that had a direct effect on hand hygiene behavior was intention. Perceived behavior control and attitude affected hand hygiene behavior indirectly. Control belief had a direct effect on perceived behavior control and had an indirect effect on intention and behavior. Behavioral belief had a direct effect on attitude and an indirect effect on intention and behavior. Conclusion: The study provides basic information for understanding nurses' hand hygiene behavior. Further testing of the model will indicate which variables can contribute to improved hand hygiene.

• Journal of Drive and Control
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• v.15 no.1
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• pp.16-27
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• 2018

Hydraulic torque load simulator is essential to test and qualify the performance of various angle control systems. Typically a flapper-type second stage servovalve is applied to the load simulator, but here the direct drive servovalve, which is a kind of one-stage valve and affected by the large flow force, is applied. Since the torque load is applied not to the stationary shaft but to the rotating shaft of the angle control system, the controlled torque of load simulator is not accurate due to the rotating speed of the angle control system. A feedforward compensator is designed and applied to minimize the disturbance-like effect. A mathematical model is derived and linearized to analyze the stability, accuracy and responsiveness of the torque load simulator. The parameter effects of a controller, servovalve, hydraulic motor, rotating spring shaft are analyzed and summarized. The goodness of the linear analysis is verified by the digital computer simulations using both the linear and nonlinear mathematical models.

• Journal of Korean Biological Nursing Science
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• v.20 no.2
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• pp.84-91
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• 2018

Purpose: The purpose of this study was to construct and test a structural equation model to investigate the risk factors of metabolic syndrome in rural women. Methods: The raw data in this study was collected from the Korean Genome and Epidemiology Study supervised by the Korea Centers for Disease Control and Prevention from 2005 to 2010. The data included physical examinations and surveys of 1,125 women, who resided in three rural areas of South Korea. The structural model in this study was composed of five latent variables: depression, stress, social support, health behavior, and metabolic syndrome. The structural equation model was used to assess the relationships among the variables. Results: The results of the study showed that depression and stress had direct effects on metabolic syndrome. Social support had a direct effect on health behavior and metabolic syndrome. Also, health behavior had a direct effect on metabolic syndrome. Conclusion: This study may serve as a guideline for interventions and strategies used to reduce metabolic syndrome in rural women.

• Child Health Nursing Research
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• v.10 no.4
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• pp.383-394
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• 2004

Purpose: This study was conducted to identify resiliency factor, to test causal relationship and effect of resiliency factors on adaptation in families of children with cancer. A conceptual framework was constructed based on McCubbin's resiliency model. Hypotheses were tested with empirical data. Method: Data were collected using self-report questionnaire from 232 families of children with cancer. The collected data were analyzed using the SAS program and LISREL program for covariance structural analysis. Result: Family hardiness and problem-solving coping had significant direct effects on adaptation in families of children with cancer. Social support had significant indirect and total effect on adaptation. Family Schema had significant direct effect on family hardiness and problem-solving coping. Problem-solving communication had a significant direct effect on family hardiness and an indirect effect on family functioning and problem-solving coping. Among the resiliency factors, family hardiness had the greatest effect on adaptation in family of children with cancer. Conclusion: The findings suggest that nursing interventions to enhance family hardiness, problem-solving coping and social support would result in an increase in adaptation in families of children with cancer. An integrated intervention that emphasizes and promotes resiliency factors should be developed and established for families of children with cancer.