• Geomechanics and Engineering
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• v.31 no.5
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• pp.453-460
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• 2022

It is essential for geotechnical engineers to conduct studies and make predictions about the stability of slopes, since collapse of a slope may result in catastrophic events. The Gaussian process regression (GPR) approach was carried out for the purpose of predicting the factor of safety (FOS) of the slopes in the study that was presented here. The model makes use of a total of 327 slope cases from Iran, each of which has a unique combination of geometric and shear strength parameters that were analyzed by PLAXIS software in order to determine their FOS. The K-fold (K = 5) technique of cross-validation (CV) was used in order to conduct an analysis of the accuracy of the models' predictions. In conclusion, the GPR model showed excellent ability in the prediction of FOS of slope stability, with an R² value of 0.8355, RMSE value of 0.1372, and MAPE value of 6.6389%, respectively. According to the results of the sensitivity analysis, the characteristics (friction angle) and (unit weight) are, in descending order, the most effective, the next most effective, and the least effective parameters for determining slope stability.

• Journal of the East Asian Society of Dietary Life
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• v.17 no.4
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• pp.580-588
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• 2007

The purpose of this study was to measure the effects of the perceived sacrifice, service quality, value and satisfaction on the intention to revisit restaurants. A total of 273 questionnaires were completed. The equation model was used to measure the causal effects. The results demonstrated that the confirmatory factor analysis model provided an excellent model fit. The modified model yielded a significantly better fit to the data than the service quality model, and accounted for a greater share of the variance in intention to revisit than the service quality model. The effects of value and service quality on intention to revisit were statistically significant in both the service quality model and modified model. The effects of perceived sacrifice and service quality on value were statistically significant in the service quality model and modified model. As expected, service quality had a significant effect on satisfaction in the modified model. Satisfaction had a significant effect on intention to revisit in the modified model. Satisfaction also had a significant effect on service quality in the service quality model. Moreover, service quality had an indirect influence on intention to revisit through value and satisfaction in the modified model. Service quality had an indirect influence on the intention to revisit through value in the service quality model. The overall findings offer strong empirical support for the intuitive notion that improving service quality can increase favorable intention to revisit, and decrease unfavorable intention to revisit.

• The Journal of the Korea Contents Association
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• v.11 no.8
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• pp.221-230
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• 2011

The purpose of this study was to examine validity of the Korean-Child Behavior Checklist: K-CBCL) as measures for emotional and behavioral problems for use with children with autism spectrum disorders. In present study, the factor of the K-CBCL was investigated, using data of 248 children with autism spectrum disorders, with 11.17 mean ages. The two factor model of Internalizing problems (Withdrawn, Somatic Complaints, Anxious/Depressed) and Externalizing problems (Delinquent Behavior, Aggressive Behavior) was investigated by the confirmatory factor analysis. The two factor model of K-CBCL was adequate for children with autism spectrum disorders. The inter-item consistency for the sub-factor of K-CBCL demonstrated on adequate reliability of the measure. Although the inter-item consistency of Withdraw, Social problems, Delinquent Behavior was not acceptable, the inter-item consistency of Internalizing, Externalizing and total problems were good. This results supported validity and reliability and suggested that K-CBCL is used to assess for emotional and behavioral problems in children with autism spectrum disorders.

• International Commerce and Information Review
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• v.9 no.2
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• pp.19-40
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• 2007

In recent, T-commerce is widely dispersed as alternative type of commerce. It is forecasted that t-commerce system is used more than e-commerce system. Therefore more and more t-commerce-related industries are also recognizing that t-commerce is a critical business model. It is needed to understand the concept of t-commerce and develop the t-commerce marketing strategy. CEO analyses consumer's behaviors according to the data about buyers and applies the advantage of t-commerce to the communication with customers. This t-commerce system plays an important role in maximizing customer satisfaction and affecting their intention to reuse it. Therefore this paper attempts to identify T-commerce critical success factors and divide between use-intention group and unuse-intention group by taking out a discriminant function by the discriminant analysis. This lays a foundation in developing T-commerce strategy. According to the discriminant function extracted, convenience factor, amusement factor, system quality factor, product perception factor are significant in the sequence of influential degree. However, usefulness factor and speedy connection factor are not significant. In result, the target hitting rate is 77.9% in the first unuse-intention group and it is 95.2% in the second use-intention group. The total discriminant target hitting rate is computed to higher value, 86.55%. The statistic package, SPSS 12.0, is used to survey and analyse data and test the hypothesis. The validity and reliability of variables are verified by both reliability analysis and factor analysis. The discriminant analysis is used to tell the difference between use-intention group and unuse-intention group.

• Journal of Ginseng Research
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• v.42 no.4
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• pp.436-446
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• 2018

Background: The potential therapeutic values of Korean Red Ginseng extract (KRGE) in autoimmune disorders of nervous system have not been fully investigated. Methods: We used an acute experimental autoimmune encephalomyelitis animal model of multiple sclerosis and determined the effects and mechanism of KRGE on spinal myelination. Results: Pretreatment with KRGE (100 mg/kg, orally) for 10 days before immunization with myelin basic protein $(MBP)_{68-82}$ peptide exerted a protective effect against demyelination in the spinal cord, with inhibited recruitment and activation of immune cells including microglia, decreased mRNA expression of detrimental inflammatory mediators (interleukin-6, interferon-${\gamma}$, and cyclooxygenase-2), but increased mRNA expression of protective inflammatory mediators (insulin-like growth factor ${\beta}1$, transforming growth factor ${\beta}$, and vascular endothelial growth factor-1). These results were associated with significant downregulation of p38 mitogen-activated protein kinase and nuclear factor-${\kappa}B$ signaling pathways in microglia/macrophages, T cells, and astrocytes. Conclusion: Our findings suggest that KRGE alleviates spinal demyelination in acute experimental autoimmune encephalomyelitis through inhibiting the activation of the p38 mitogen-activated protein kinase/nuclear factor-${\kappa}B$ signaling pathway. Therefore, KRGE might be used as a new therapeutic for autoimmune disorders such as multiple sclerosis, although further investigation is needed.

• The Journal of Society for e-Business Studies
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• v.19 no.1
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• pp.15-42
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• 2014

Cloud storage service has the potential to be a core infrastructure for the future mobile and Internet service; thus related service providers have been investing in it and trying to attract as many users as possible. In addition, those need to find out what motivates the users to keep using their service not only to attract new customers but also to secure their subscribers. Therefore, this study will examine its relationship with user's motivation based on the extended TAM model with external variables for objective research about continuous use of cloud storage service. As a result, it was found that personal innovativeness, self efficacy, functional attributes, and psychological switching cost influence the continuous use of cloud storage service. Also, it is expected they can guide service providers to the right track when setting up their business strategy in the future.

• Journal of the Korean Solar Energy Society
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• v.23 no.3
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• pp.45-53
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• 2003

This paper presents a study on the power factor improvement of V47- 660 [kW] Wind Turbine Generation System (WTGS) in Jeju wind farm, as a model system in this paper. In this system, the power factor correction is controlled by the conventional method with power condensor banks. Also, this system has only four bank steps, and each one capacitor bank step is cut in every one second when the generator has been cut in. This means that it is difficult to compensate the reactive power exactly according to the variation of them. Actually, model system has very low power factor in the area of low wind speed, which is almost from 4 to 6 [m/s]. This is caused by the power factor correction using power condenser bank. To improve the power factor in the area of low wind speed, we used the static var compensator(SVC) using current controlled PWM power converter using IGBT switching device. Finally, to verify the proposed method, the results of computer simulation using Psim program are presented to support the discussions.

• Earthquakes and Structures
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• v.20 no.2
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• pp.133-148
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• 2021

The paper presents a simplified force-based seismic design procedure for the preliminary design of steel haunch retrofitting for the seismic upgrade of deficient RC frames. The procedure involved constructing a site-specific seismic design spectrum for the site, which is transformed into seismic base shear coefficient demand, using an applicable response modification factor, that defines base shear force for seismic analysis of the structure. Recent experimental campaign; involving shake table testing of ten (10), and quasi-static cyclic testing of two (02), 1:3 reduced scale RC frame models, carried out for the seismic performance assessment of both deficient and retrofitted structures has provided the basis to calculate retrofit-specific response modification factor Rretrofitted. The haunch retrofitting technique enhanced the structural stiffness, strength, and ductility, hence, increased the structural response modification factor, which is mainly dependent on the applied retrofit scheme. An additional retrofit effectiveness factor (ΩR) is proposed for the deficient structure's response modification factor Rdeficient, representing the retrofit effectiveness (ΩR=Rretrofitted /Rdeficient), to calculate components' moment and shear demands for the retrofitted structure. The experimental campaign revealed that regardless of the deficient structures' characteristics, the ΩR factor remains fairly the unchanged, which is encouraging to generalize the design procedure. Haunch configuration is finalized that avoid brittle hinging of beam-column joints and ensure ductile beam yielding. Example case study for the seismic retrofit designs of RC frames are presented, which were validated through equivalent lateral load analysis using elastic model and response history analysis of finite-element based inelastic model, showing reasonable performance of the proposed design procedure. The proposed design has the advantage to provide a seismic zone-specific design solution, and also, to suggest if any additional measure is required to enhance the strength/deformability of beams and columns.

• Bulletin of the Korean Chemical Society
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• v.31 no.7
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• pp.2039-2042
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• 2010

• Journal of the Korean Society of Safety
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• v.9 no.1
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• pp.3-8
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• 1994

This paper has described the analysis of the Stress Intensity Factor behaviour of a short crack Initiated from notch tip. The model for finite element analysis is a double edge notched specimen. The parameters used in this study are crack length and notch root curvature radius.