• 대한화학회지
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• 제57권5호
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• pp.554-559
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• 2013

본 연구에서는 ${\beta}$-D-glucopyranose 분자의 hydroxymethyl group의 두 torsion angle의 변화에 따른 포텐셜 에너지의 변화를 진공 상태와 implicit water 상태에서 연구하였으며 이를 통해 Solvation Energy가 구조에 미치는 영향에 대해서 알아보았다. 계산에 사용한 프로그램은 AMBER package였으며, force field는 GLYCAM_06을 사용하였다. Solvation model은 Hawkins, Cramer, Truhlar 등이 제안한 generalized Born model을 사용하였다. 계산 결과, methyl hydroxyl group 내의 hydroxyl group이 고리구조의 hydroxyl group과 강한 수소결합이 가능한 영역에서 많은 변화가 일어났다. 이를 통해 solvation effect로 인해서 수소 결합의 중요성이 감소했다는 결론을 내렸다.

• 한방안이비인후피부과학회지
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• 제28권3호
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• pp.76-87
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• 2015

Objectives : Allergic rhinitis is highly increased in these days. We aimed to investigate therapeutic effect ofShinchulsanby observing changes in blood cells and the protein expression level of IL-4 in spleen of Sprague-Dawley(SD) rats with allergic rhinitis.Methods : Fifteen SD rats were divided into three groups: normal, control, and sample group. Allergic rhinitis was induced in the control and sample group by intraperitional and intranasal sensitization with 0.1% and 0.4% Ovalbumin solution. ThenShinchulsanwas orally administered only to the sample group for 28 days, while the rats in the control group was given normal saline.Results : 1.Shinchulsanshowed significantly decreased eosinophil level on the serum of the rat model.2.Shinchulsanshowed significantly decreased IgE level on the serum of the rat model.3.Shinchulsanshowed significantly decreased the protein expression levels of IL-4 in spleen of the rat model.4.Shinchulsanhad no hepatoxicity, according to AST and ALT on the serum.Conclusion : According to the above results, it is considered thatShinchulsanis helpful in treatment of allergic rhinitis.

• 천문학회지
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• 제53권6호
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• pp.139-147
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• 2020

The sunspot area is a critical physical quantity for assessing the solar activity level; forecasts of the sunspot area are of great importance for studies of the solar activity and space weather. We developed an innovative hybrid model prediction method by integrating the complementary ensemble empirical mode decomposition (CEEMD) and extreme learning machine (ELM). The time series is first decomposed into intrinsic mode functions (IMFs) with different frequencies by CEEMD; these IMFs can be divided into three groups, a high-frequency group, a low-frequency group, and a trend group. The ELM forecasting models are established to forecast the three groups separately. The final forecast results are obtained by summing up the forecast values of each group. The proposed hybrid model is applied to the smoothed monthly mean sunspot area archived at NASA's Marshall Space Flight Center (MSFC). We find a mean absolute percentage error (MAPE) and a root mean square error (RMSE) of 1.80% and 9.75, respectively, which indicates that: (1) for the CEEMD-ELM model, the predicted sunspot area is in good agreement with the observed one; (2) the proposed model outperforms previous approaches in terms of prediction accuracy and operational efficiency.

• 한국수소및신에너지학회논문집
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• 제33권5호
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• pp.499-506
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• 2022

This study proposes kinetic parameters of Ru catalyst for steam methane reforming (SMR). First, extensive experiments are performed under different SMR conditions to evaluate performance of the catalyst in SMR. Second, a kinetic model is designed and developed for parameter estimation and validation using gPROMS. Finally, estimated parameters are fitted to the kinetic model and then, the model results are compared with the experimental data. The model results are in a good agreement with the experimental data.

• 한국식품저장유통학회지
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• 제30권2호
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• pp.224-234
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• 2023

We analyzed the major quality characteristics of red pepper powders from various regions and predicted these characteristics nondestructively using shortwave infrared hyperspectral imaging (HSI) technology. We conducted partial least squares regression analysis on 70% (n=71) of the acquired hyperspectral data of the red pepper powders to examine the major quality characteristics. R_c² values of ≥0.8 were obtained for the ASTA color value (0.9263) and capsaicinoid content (0.8310). The developed quality prediction model was validated using the remaining 30% (n=35) of the hyperspectral data; the highest accuracy was achieved for the ASTA color value (R_p²=0.8488), and similar validity levels were achieved for the capsaicinoid and moisture contents. To increase the accuracy of the quality prediction model, we conducted spectrum preprocessing using SNV, MSC, SG-1, and SG-2, and the model's accuracy was verified. The results indicated that the accuracy of the model was most significantly improved by the MSC method, and the prediction accuracy for the ASTA color value was the highest for all the spectrum preprocessing methods. Our findings suggest that the quality characteristics of red pepper powders, even powders that do not conform to specific variables such as particle size and moisture content, can be predicted via HSI.

• Journal of Magnetics
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• 제21권3호
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• pp.431-436
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• 2016

In the design of transformer winding, natural vibration frequency is an important parameter. This paper presents a 2D model to calculate axial vibration natural frequency of power transformer winding based on the elastic dynamics theory, and according to the elastic support equivalent principle of radial pressboards. The 3D model to calculate natural vibration frequency can be simplified as a 2D one as the support of pressboards on the winding is same. It is verified that results of the 2D model are consistent with those of 3D one, but the former can achieve much higher calculation efficiency. It shows that increasing the width and number of pressboards can improve axial natural frequency through formula analysis and simulation, and also the relations between the changes of axial pre-compression and axial natural vibration frequency on the windings are investigated. Finally, the proposed 2D model's effectiveness is proved when compared with tested ones.

• 한국경영과학회:학술대회논문집
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• 한국경영과학회/대한산업공학회 2005년도 춘계공동학술대회 발표논문
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• pp.975-982
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• 2005

The purpose of the Gage R&R study is to determine whether a measurement system is adequate for monitoring a process. If the measurement system variation is small relative to the process variation, then the measurement system is deemed 'adequate'. The sources of variation associated with the measurement system are compared using an analysis of variance (ANOVA) model, in general. A typical ANOVA model used in a standard Gage R&R study is the two-factor random effect model. Then, the ANOVA partitions the total variation into three categories: repeatability, reproducibility, part variation. However, if the process variation possesses the between group variation, within group variation, and within-part variation, these variations can cause the measurement system evaluation to provide misleading results. That is, in the standard Gage R&R study these variations affect the estimate of repeatability, reproducibility, or both. This paper presents a four-factor nested factorial ANOVA model which explicitly considers these variations for the Gage R&R study. The variance component estimates are derived by setting the EMS equations equal to the corresponding mean square from the ANOVA table and solving. And the proposed model is compared with the standard Gage R&R model.

• 한국의류학회지
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• 제34권8호
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• pp.1341-1351
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• 2010

The Korean jean market has become increasingly competitive due to the increased imports of global brands. This study is to understand the purchase behaviors of Korean college students toward foreign brand jeans to help Korean jean brands enhance their competitive advantages over foreign brand jeans in the Korean market. Considering perceptions of Korean consumers toward foreign brands and traditional value changes, this study proposed a research model incorporating two extended behavioral intention (BI) models, Lee's modified BI model and Ajzen's theory of planned behavior. To test the research model, a total of 240 valid data sets were collected from college students in Busan, Korea. Structural and measurement models were estimated using LISREL 8.80. Because face saving failed to attain internal validity, the research model was revised to eliminate face saving. The findings indicated that perceived behavioral control had the strongest direct influence on purchase intentions of Korean college students for foreign brand jeans. Group conformity and subjective norm had non-significant direct impacts on purchase intention, whereas group conformity had an indirect impact on purchase intention through attitude. Based on the findings, theoretical and managerial implications were provided.

• 한방재활의학과학회지
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• 제25권3호
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• pp.37-49
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• 2015

Objectives This study was designed to collect studies about the Pharmacopuncture used for Rheumatoid arthritis model through analysis on Korean medicine prescriptions of Korean journals objective. Methods We searched 29 studies related Pharmacopuncture treatment of Rheumatoid arthritis model via Korean medicine web database. Results 29 studies were published 2007 to 2015. There were 4 studies have positive control group and negative control group, and 25 studies were design only negative control group. 15 studies were published 2007, 5 studies were published 2008, 1 study was published 2010, 2 studies were published 2011, 5 studies were published 2012, 1 study was published 2013. There were 20 Pharmacopuncture treated for Rheumatoid arthritis mouse or rat model. Most of these studies were effective to treat of Rheumatoid arthritis model. Conclusions These results suggested that Pharmacopuncture is effective treatment to Rheumatoid arthritis model and we need continuously agonize and research more effective therapy method.

• 보건행정학회지
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• 제27권2호
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• pp.149-156
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• 2017

Background: This study was conducted to evaluate the performance of the Hierarchical Condition Category (HCC) model, identify potentially high-cost patients, and examine the effects of adding prior utilization to the risk model using Korean claims data. Methods: We incorporated 2 years of data from the National Health Insurance Services-National Sample Cohort. Five risk models were used to predict health expenditures: model 1 (age/sex groups), model 2 (the Center for Medicare and Medicaid Services-HCC with age/sex groups), model 3 (selected 54 HCCs with age/sex groups), model 4 (bed-days of care plus model 3), and model 5 (medication-days plus model 3). We evaluated model performance using $R^2$ at individual level, predictive positive value (PPV) of the top 5% of high-cost patients, and predictive ratio (PR) within subgroups. Results: The suitability of the model, including prior use, bed-days, and medication-days, was better than other models. $R^2$ values were 8%, 39%, 37%, 43%, and 57% with model 1, 2, 3, 4, and 5, respectively. After being removed the extreme values, the corresponding $R^2$ values were slightly improved in all models. PPVs were 16.4%, 25.2%, 25.1%, 33.8%, and 53.8%. Total expenditure was underpredicted for the highest expenditure group and overpredicted for the four other groups. PR had a tendency to decrease from younger group to older group in both female and male. Conclusion: The risk adjustment models are important in plan payment, reimbursement, profiling, and research. Combined prior use and diagnostic data are more powerful to predict health costs and to identify high-cost patients.