• The Transactions of the Korean Institute of Electrical Engineers C
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• v.53 no.8
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• pp.420-424
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• 2004

This paper presents experimental data from model windings with different arrangement of coil in order to provide information to design a 22.9kV class HTS transformer. Before experiment, the composite insulation of two different type of HTS transformers are investigated. The first basic of investigation is a breakdown characteristic of liquid nitrogen and flashover characteristic on the GFRP surface under ac and impulse, The second investigation is insulation design, manufacture and test of model windings. These include a AC withstand voltage test of 50 kV rms and a lighting impulse test of 150 kV at peak.

• Journal of the Korea institute for structural maintenance and inspection
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• v.19 no.5
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• pp.92-103
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• 2015

Box-Wilson experimental design method, known as central composite design, is the design of any information-gathering exercises where variation is present. This method was devised to gather as much data as possible in spite of the low design cost. This method was employed to model the effect of mixing factors on several performances of 60 MPa high strength self compacting concrete and to numerically calculate the optimal mix proportion. The nonlinear relations between factors and responses of HSSCC were approximated in the form of second order polynomial equation. In order to characterize five performances like compressive strength, passing ability, segregation resistance, manufacturing cost and density depending on five factors like water-binder ratio, cement content, fine aggregate percentage, fly ash content and superplasticizer content, the experiments were made at the total 52 experimental points composed of 32 factorial points, 10 axial points and 10 center points. The study results showed that Box-Wilson experimental design was really effective in designing the experiments and analyzing the relation between factor and response.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.34 no.1
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• pp.42-48
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• 2006

In this study, a repetitive response surface enhancement technique (RRSET) is proposed as a new system approximation method for the efficient multidisciplinary design and optimization (MDO). In order to represent the highly nonlinear behavior of the response with second order polynomials, RRSET introduces a design space transformation using stretching functions and repetitive response surface improvement. The tentative optimal point is repetitively included to the set of experimental points to better approximate the response surface of the system especially near the optimal point, hence a response surface with significantly improved accuracy can be generated with very small experimental points and system iterations. As a system optimizer, the simulated annealing, which generates a global design solution is utilized. The proposed technique is applied to several numerical examples, and demonstrates the validity and efficiency of the method. With its improved approximation accuracy, the RRSET can contribute to resolve large and complex system design problems under MDO environment.

• Environmental Engineering Research
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• v.15 no.2
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• pp.63-70
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• 2010

In this study, the response surface method and experimental design were applied as an alternative to conventional methods for the optimization of coagulation tests. A central composite design, with 4 axial points, 4 factorial points and 5 replicates at the center point were used to build a model for predicting and optimizing the coagulation process. Mathematical model equations were derived by computer simulation programming with a least squares method using the Minitab 15 software. In these equations, the removal efficiencies of turbidity and total organic carbon (TOC) were expressed as second-order functions of two factors, such as alum dose and coagulation pH. Statistical checks (ANOVA table, $R^2$ and $R^2_{adj}$ value, model lack of fit test, and p value) indicated that the model was adequate for representing the experimental data. The p values showed that the quadratic effects of alum dose and coagulation pH were highly significant. In other words, these two factors had an important impact on the turbidity and TOC of treated water. To gain a better understanding of the two variables for optimal coagulation performance, the model was presented as both 3-D response surface and 2-D contour graphs. As a compromise for the simultaneously removal of maximum amounts of 92.5% turbidity and 39.5% TOC, the optimum conditions were found with 44 mg/L alum at pH 7.6. The predicted response from the model showed close agreement with the experimental data ($R^2$ values of 90.63% and 91.43% for turbidity removal and TOC removal, respectively), which demonstrates the effectiveness of this approach in achieving good predictions, while minimizing the number of experiments required.

• The Journal of Korean Physical Therapy
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• v.31 no.5
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• pp.261-265
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• 2019

Purpose: This study examined the effects of Vojta therapy on the respiratory function in young male smokers. Methods: Three subjects were tested using the ABA design for Single-subject Experimental Research Design. This study was conducted with the baseline, intervention, and follow-up phase. Intervention was conducted three to four times a week for 20 minutes per times and a total of 25 sessions. The respiratory function was measured using a Spirometer. Results: The results of Forced Vital Capacity and Forced Expiratory Volume at one second for all subjects showed improvements in the intervention phase over the baseline phase. In the follow-up phase, the improved ability was still maintained or slightly reduced. Conclusion: Vojta therapy used on young male smokers was effective in both FVC and FEV1. In other words, the Vojta therapy worked effectively in improving the respiratory function. In future studies, it is necessary to have a control group and increase the number of trials in order to generalize the effect of Vojta therapy.

• Journal of Korean Academy of Nursing
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• v.38 no.3
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• pp.383-392
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• 2008

Purpose: This study was to analyze the sustainable effects of cardiopulmonary resuscitation (CPR) reeducation on nurses' knowledge and skills. Methods: A repeated experimental design was used for a single sample group of 47 nurses working for a general hospital. The nurses were tested on their skill of CPR 3 times at an interval of 4 m1onths. In order to test nurses' knowledge and skills, the researcher used a CPR assessment program linked to an adult practice doll (Anne). Results: 1) The amount of decrease of nurses' knowledge about CPR between points of time was wide between first and second points of time but small between the second and third time owing to the effects of reeducation between the two points of time. 2) Nurses' skills between the first and second time dropped but they improved between the second and third time owing to the effects of reeducation. Conclusion: As confirmed by the above findings, reeducation of CPR clearly affects nurses' knowledge and skills. Given the fact that the same period of time (4 months) elapsed between the 3 tests, it could be argued that the reeducation at the second test served to maintain nurses' knowledge and enhance their skills.

• Fashion & Textile Research Journal
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• v.18 no.4
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• pp.498-508
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• 2016

The purpose of this study is to develop an aesthetic and functional bicycle wear for new senior women in their 50s and 60s. Based on the results of the survey, we developed bicycle wear that is friendly to bicycling posture and reflects the preference of new senior women. The results are as followed: First, emphasis is placed on the simple and functional design of the experimental wear consisting of jacket and pants. Jacket is different from the color scheme with the armhole princess line in order for the waistline to look slim. Pants are designed to hold the leg muscles tightly in order to help reduce the muscle fatigue on the bicycle ride. Second, cutting lines and coloring materials are used for the wearer to look slim and the safety of the wearer is planned to secure by inserting the reflective material along the cutting lines on the bicycle ride. Third, the pattern of the experimental wear is designed in consideration of the riding motion of the bicycle. Jacket is designed to have back length longer than front length as compared to the bicycle wears available on the market. Sewing lines in the armpit are designed to be eliminated in order to move the arms smoothly on the ride. Pants are designed to minimize the seam line in consideration of the movement of muscles and ligaments and the experimental wear is produced by combining the material with the functions of cool comfort and stretch.

• Korean Journal of Human Ecology
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• v.17 no.6
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• pp.1205-1213
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• 2008

Material is a factor for maximizing formative aspect among fashion design factors. Therefore, central axis of modern fashion is performing various trials for escaping from existing cloth and searching for artistic value. Especially, Korean paper is a formative material, which is manufactured through traditional manual work in Korea. The material is used in various fields on the basis of its aesthetic feature. Especially, fashion field performs handcraft activity on the basis of mulberry pulp, which is a prime material of Korean paper. Because the activity can be reinterpreted by world designers, who want to find motive of fashion material in the third world, it is necessary to perform experimental study for developing expressive form on the basis of diversity of Korean paper material. Therefore, the purpose of this study is to perform experimental study by focusing on the development of Korean paper material in order to express formative feature. The study purposes are as follows. The first purpose is to reinterprete the theory through actual work of fiber formation using Korean paper in the current flow where art and design field are fused and compromised. The second purpose is to suggest vision of material development on the basis of formative feature to fashion world focusing its eyesight to Asia and the third countries. The study results are as follows. First, Korean paper has been evaluated as proper material for the fusion of design and art because of its handicraft feature, long-term preservation, heat insulation, absorption, diversity and eastern feature. Second, the study performed various trials for artistic dress material by developing 12 Korean paper works and suggested the development of new material on the basis of formative feature of modem fashion industry.

• Journal of Korean Society for Quality Management
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• v.39 no.3
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• pp.365-376
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• 2011

Robust design (RD) has emerged as a key feature in process design and development for more than twenty years. Many researchers and industrial engineers around the world have invested their intensive efforts to develop and apply RD in many fields in order to improve quality of output products. However, there is also room for improvement. The primary objective of this research is to determine "robust formulation" of a medicine by checking its gelation index. In order to achieve this target, based on the nature of problem, at first, a customized experimental format is designed for obtaining data. Second, time-depended responses based models are developed by the proposed inverse problem (IP) methodology. Third, an RD model based on mean square error (MSE) concept is introduced for time-depended responses. Finally, the proposed approach is illustrated by a case study while comparing obtained results to the response surface methodology (RSM) approach.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.22 no.1
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• pp.64-71
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• 1997

Digital communication channels are imparied by linear effects such as dispersion, ISI(intersymbol Interference), fading phenomenon etc. But, the practical channel equalization system is required to design for compensating the nonlinear distortion caused by harmonic distortion etc. This paper is a study on the performance of nonlinear channel equalization using RBF(Radial Basis Funclion) network, which has the equivalent structure to the optimal Basian filter. Expecially, the variance of RBF network is modifiedby nonlinear polynomial filters to compare the convergence characteristic of nonlinear channel equalization. Experimental results show that the modified RBF network achieves the faster convergence property than conventional RBF network. Moreover, the RBF network ofhigher order variance modified represents the better performance than that of lower order variance in the bandpass channels and second/third order polynomial channels.