• Journal of the Computational Structural Engineering Institute of Korea
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• v.30 no.2
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• pp.185-189
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• 2017

The purpose of earthquake resistant design for typical bridges is the 'No Collapse Design' allowing emergency vehicles just after earthquakes. The Roadway Bridge Design Code provides design provisions to carry out such 'No Collapse Design' with a ductile mechanism and response modification factors given for connections and substructure play key role in this procedure. In case of response modification factors for substructure, the Roadway Bridge Design Code provides values considering ductility and redundancy. On the other hand, 'AASHTO LRFD Bridge Design Specifications' provides values considering additionally an artificial factor according to the bridge importance categories divided into critical, essential and others. In this study, a typical bridge with steel bearing connections and reinforced concrete piers is selected and different response modification factors for substructure are applied with design conditions given in the Roadway Bridge Design Code. Based on the comparison study of the design results, supplementary measures are suggested required by applying different response modification factors for substructure.

• Structural Engineering and Mechanics
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• v.46 no.6
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• pp.755-773
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• 2013

One of the main requirements of the seismic design codes must be its easy application by structural engineers. The use of practically-applicable models or simplified models as single-degree-of-freedom (SDOF) systems is a good alternative to achieve this condition. In this study, deterministic and probabilistic response transformation factors are obtained to evaluate the response in terms of maximum ductility and maximum interstory drifts of multi-degree-of-freedom (MDOF) systems based on the response of equivalent SDOF systems. For this aim, five steel frames designed with the Mexican City Building Code (MCBC) as well as their corresponding equivalent SDOF systems (which represent the characteristics of the frames) are analyzed. Both structural systems are subjected to ground motions records. For the MDOF and the simplified systems, incremental dynamic analyses IDAs are developed in first place, then, structural demand hazard curves are obtained. The ratio between the IDAs curves corresponding to the MDOF systems and the curves corresponding to the simplified models are used to obtain deterministic response transformation factors. On the other hand, demand hazard curves are used to calculate probabilistic response transformation factors. It was found that both approaches give place to similar results.

• Korean Management Science Review
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• v.24 no.2
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• pp.73-80
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• 2007

Robust Design(RD) is a cost-effective methodology to determine the optimal settings of control factors that make a product performance insensitive to the influence of noise factors. To better facilitate the robust design optimization, a dual response surface approach, which models both the process mean and standard deviation as separate response surfaces, has been successfully accepted by researchers and practitioners. However, the construction of response surface approximations has been limited to problems with only a few variables, mainly due to an excessive number of experimental runs necessary to fit sufficiently accurate models. In this regard, an innovative response surface approach has been proposed to investigate robust design optimization problems with larger number of variables. Response surfaces for process mean and standard deviation are partitioned and estimated based on the multi-level approximation method, which may reduce the number of experimental runs necessary for fitting response surface models to a great extent. The applicability and usefulness of proposed approach have been demonstrated through an illustrative example.

• Journal of the Earthquake Engineering Society of Korea
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• v.23 no.4
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• pp.201-209
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• 2019

Response modification factors of school facilities for non-seismic RC moment frames with partial masonry infills in 'Manual for Seismic Performance Evaluation and Retrofit of School Facilities' published in 2018 were investigated in the preceding study. However, since previous studies are based on 2D frame analysis and limited analysis conditions, additional verification needs to be performed to further apply various conditions including orthogonal effect of seismic load. Therefore, this study is to select appropriate response modification factors of school facilities for non-seismic RC moment frames with partial masonry infills by 3D frame analysis. The results are as follows. An appropriate response modification factor for non-seismic RC moment frames with partial masonry infills is proposed as 2.5 for all cases if the period is longer than 0.6 seconds. Also if the period is less than 0.4 seconds and the ratio of shear-controlled columns is less than 30%, 2.5 is chosen too. However, if the period is less than 0.4 seconds and the ratio of shear-controlled columns is higher than 30%, the response modification factor shall be reduced to 2.0. If the period is between 0.4 and 0.6 seconds, then linearly interpolates the response correction factor.

• Journal of Korean Public Health Nursing
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• v.36 no.1
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• pp.59-74
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• 2022

Purpose: This study aimed to identify the factors affecting the emergency response ability to develop an education program to strengthen the emergency response ability of caregivers having the highest probability of discovering emergency situations. Methods: This study is a descriptive research study conducted by 204 caregivers working in elderly care facilities and home care centers located in one area. The collected data were analyzed by independent t-test, one-way analysis of variance (ANOVA), Pearson's correlation, and multiple linear regression using the Statistical Package for the Social Sciences (SPSS) 25.0 statistical program. Results: First aid knowledge was related to work time (F=3.52, p=.008), number of care people (F=2.58, p=.038), workplace (F=6.76, p=.001), and self-efficacy (F=3.70, p=.026), and the ability to cope with emergency situations showed a statistically significant difference in education level (F=3.58, p=.015). There was a positive correlation between self-efficacy and emergency response ability (r=.179, p<.05), and the factors affecting emergency response ability were education level (β=-.164, p=.050), workplace (β=.290, p=.023), and self-efficacy (β=.103, p=.022). Conclusion : Factors influencing the improvement of caregivers' ability to cope with emergency situations, workplace, education level, and self-efficacy were found. Thus, it is suggested to develop and apply an emergency education program to increase self-efficacy and consider the workplace and educational level.

• The Journal of Industrial Distribution & Business
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• v.10 no.7
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• pp.71-82
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• 2019

Purpose - This study aims to identify the priorities of medical service quality improvement by customer satisfaction characteristics and potential customer satisfaction improvement (PCSI) index based on the dualistic quality classification of Kano Model (1984) for Comprehensive Health Screeening Center in General Hospitals and Centers only for Comprehensive Health Screening and suggest a direction for future improvement. Research design, data, and methodology - Through advanced research on health screening medical service quality, this study set four service quality factors, including tangible, human, process and supportive factors, and 39 measurement items. Based on these items, the study used 117 questions, which consist of dualistic quality factors, customer satisfaction coefficients, positive and negative questions for PCSI index and questions for current satisfaction. 300 effective samples were collected for adults in their 20s who experienced health screening service in Seoul, Gyeonggi-do and Incheon within the past two years. Collected data were input in the quality evaluation duality table to categorize quality factors and calculate customer satisfaction coefficients by Timko(1993). The study also analyzed PCSI index in comparison with current satisfaction and identified priorities in quality improvement. Results - It was found that the most urgent factors to improve the quality in both groups were adequate waiting hours and emergency response for complications, which are process factors classified as unitary quality. It is urgently needed to improve the quality as the PCSI index was high in supportive factors (complaint response team) as attractive quality in Comprehensive Health Screening Center in General Hospitals and in process factors (prevention of infection) as unitary quality in Centers only for Comprehensive Health Screening. As the PCSI index was low in space use as a tangible factor, it was found that the current level can be maintained instead of improvement. Conclusions - To improve the health screening medical service quality, it is required to focus on process factors (adequate waiting hours, emergency response for complications, prevention of infection) and supportive factors (complaint response team) among service qualities perceived by users. It is proposed to ensure continuous efforts to manage and reinforce priorities as a direction for future improvement in health screening service.

• Korean Journal of Child Studies
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• v.34 no.1
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• pp.141-159
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• 2013

This study was conducted in order to develop an observation scale for analyzing the responses of child and therapist in child-centered play therapy in terms of item discrimination, validity, and reliability. The observation scale was developed on the basis of child-centered play therapy literature, the author's experience of child-centered play therapy, the observation of video tapes of play therapy session, and discussions with child-centered play therapy experts. The participants in this study were 54 children aged from 4 to 9 years old who have emotional and behavioral problems, and 7 therapists who consult with the children. The reliability of factors, as measured by inter-rater reliability and Cronbach's', ranged from .72 to .77. The results of factor analysis identified 2 factors and 21 items associated with the reponses of the children, and 2 factors and 19 items associated with the responses of the therapists. The significant factors identified were as follows; (1) the child's response style; (2) the child's response content (adaptability, initiation, structuring, flexibility); (3) the therapist's response style, and (4) the therapist's response content (facilitative response, structuring, nonfacilitative response). In conclusion, these results demonstrated that the observation scale provides a valid and reliable means of analyzing the responses of child and therapist in child-centered play therapy.

• Journal of Korean Institute of Industrial Engineers
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• v.39 no.5
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• pp.361-366
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• 2013

Prediction of process parameters is very important in parameter design. If predictions are fairly accurate, the quality improvement process will be useful to save time and reduce cost. The concept of dual response approach based on response surface methodology has widely been investigated. Dual response approach may take advantages of optimization modeling for finding optimum setting of input factor by separately modeling mean and variance responses. This study proposes an alternative dual response approach based on machine learning techniques instead of statistical analysis tools. A hybrid neural network-genetic algorithm has been proposed for the purpose of parameter design. A neural network is first constructed to model the relationship between responses and input factors. Mean and variance responses correspond to output nodes while input factors are used for input nodes. Using empirical process data, process parameters can be predicted without performing real experimentations. A genetic algorithm is then applied to find the optimum settings of input factors, where the neural network is used to evaluate the mean and variance response. A drug formulation example from pharmaceutical industry has been studied to demonstrate the procedures and applicability of the proposed approach.

• Structural Engineering and Mechanics
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• v.68 no.2
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• pp.159-170
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• 2018

This paper aims to develop response modification factors for stiffness degrading structures by incorporating soil-structure interaction effects. A comprehensive parametric study is conducted to investigate the effects of key SSI parameters, natural period of vibration, ductility demand and hysteretic behavior on the response modification factor of soil-structure systems. The nonlinear dynamic response of 6300 soil-structure systems are studied under two ensembles of accelograms including 20 recorded and 7 synthetic ground motions. It is concluded that neglecting the stiffness degradation of structures can results in up to 22% underestimation of inelastic strength demands in soil-structure systems, leading to an unexpected high level of ductility demand in the structures located on soft soil. Nonlinear regression analyses are then performed to derive a simplified expression for estimating ductility-dependent response modification factors for stiffness degrading soil-structure systems. The adequacy of the proposed expression is investigated through sensitivity analyses on nonlinear soil-structure systems under seven synthetic spectrum compatible earthquake ground motions. A good agreement is observed between the results of the predicted and the target ductility demands, demonstrating the adequacy of the expression proposed in this study to estimate the inelastic demands of SSI systems with stiffness degrading structures. It is observed that the maximum differences between the target and average target ductility demands was 15%, which is considered acceptable for practical design purposes.

• Korean Journal of Clinical Pharmacy
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• v.18 no.2
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• pp.75-83
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• 2008

Purpose: Currently lung cancer ranks second in cancer for incidence rate and is a disease that ranks first for a death rate by cancerous growth because it is already advanced at the time of diagnosis. The purpose of this paper was to analyze the factors that affect the effectiveness of and rash occurrence by Epidermal Growth Factor Receptor Tyrosine Kinase Inhibitor (EGFR TKI) in patients with non-small cell lung cancer. Methods: A retrospective chart review of 100 patients, who took EGFR TKI (erlotinib, gefitinib) among patients who were diagnosed with non-small cell lung cancer in a Hospital in Korea between May 2005 and February 2008, was conducted. The drug effectiveness was evaluated by Response Evaluation Criteria In Solid Tumor. Results: EGFR mutation was the only factor associated with drug response (complete response and partial response). When stable disease was added to drug response as the evaluation parameter, ECOG and rash as well as EGFR mutation were found to be important factors. Survival, however, was not affected by EGFR mutation. The factors influenced on survival were older age (${\geq}65$), low ECOG ($1{\sim}2$), adenocarcinoma and rash. In the case of rash, group with EGFR mutation or low ECOG showed significantly higher chance of occurrence. There was no significant difference in rash occurrence between gefitinib and erlotinib groups. Conclusions: Based on the results, EGFR mutation positive and low ECOG ($1{\sim}2$) were significantly important factors for both effectiveness of EGFR TKI and rash occurrence. Also, rash itself was found to be an independently significant factor for the disease control and survival. Therefore, while administering EGFR TKI, patients who have the factors associated with rash occurrence should be closely monitored for effective and safe drug therapy.