• International Journal of Aeronautical and Space Sciences
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• v.17 no.3
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• pp.409-422
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• 2016

A parametric study based on an unsteady mathematical model of a pyrotechnically actuated device was performed for design optimization. The model simulates time histories for the chamber pressure, temperature, mass transfer and pin motion. It is validated through a comparison with experimentally measured pressure and pin displacement. Parametric analyses were conducted to observe the detailed effects of the design parameters using a validated performance analysis code. The detailed effects of the design variables on the performance were evaluated using the one-at-a-time (OAT) method, while the scatter plot method was used to evaluate relative sensitivity. Finally, the design optimization was conducted by employing a genetic algorithm (GA). Six major design parameters for the GA were chosen based on the results of the sensitivity analysis. A fitness function was suggested, which included the following targets: minimum explosive mass for the uniform ignition (small deviation), light casing weight, short operational time, allowable pyrotechnic shock force and finally the designated pin kinetic energy. The propellant mass and cross-sectional area were the first and the second most sensitive parameters, which significantly affected the pin's kinetic energy. Even though the peak chamber pressure decreased, the pin kinetic energy maintained its designated value because the widened pin cross-sectional area induced enough force at low pressure.

• Nuclear Engineering and Technology
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• v.49 no.7
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• pp.1423-1430
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• 2017

Detonation cell width is an important parameter in hydrogen explosion assessments. The experimental data on gas detonation are statistically analyzed to establish a universal method to numerically predict detonation cell widths. It is commonly understood that detonation cell width, ${\lambda}$, is highly correlated with the characteristic reaction zone width, ${\delta}$. Classical parametric regression methods were widely applied in earlier research to build an explicit semiempirical correlation for the ratio of ${\lambda}/{\delta}$. The obtained correlations formulate the dependency of the ratio ${\lambda}/{\delta}$ on a dimensionless effective chemical activation energy and a dimensionless temperature of the gas mixture. In this paper, support vector regression (SVR), which is based on nonparametric machine learning, is applied to achieve functions with better fitness to experimental data and more accurate predictions. Furthermore, a third parameter, dimensionless pressure, is considered as an additional independent variable. It is found that three-parameter SVR can significantly improve the performance of the fitting function. Meanwhile, SVR also provides better adaptability and the model functions can be easily renewed when experimental database is updated or new regression parameters are considered.

• Journal of Fashion Business
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• v.9 no.3
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• pp.64-87
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• 2005

The purpose at this study is to develop the appropriate bodice model for Chinese women in order to contribute to the improvement of fitness at clothing products that are exported to China. The sample group was the subject of 149 persons with the standard body shape at 19-24 years old women who reside in Beijing and Shanghai, China. The data analysis is processed for statistics using SPSSWIN 10.0 PROGRAM, and the used analysis methods are technical statistics analysis, factor analysis, group analysis, and one-way ANOVA. The outcome of this study is summarized as follows. 1. Prior to develop the tight-fitting shape of bodice model, the body classification approach by the posture and type of bending and stretching is selected to use 6 index items, and the body types are classified into bent body, right body, and pull-back body. 2. The average body size of standard body shape had 3 times of wearing experiment based on the tight-fitting shape of ESMOD bodice block drawing, and the system was corrected and supplemented to present the final bodice block drawing. 3. Comparisons have been made based on the center front line, center back line and chest circumference for each of existing bodice block for Chinese women, existing bodice block for Korean women and the combination of the bodice block under this study.

• Journal of Navigation and Port Research
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• v.29 no.10 s.106
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• pp.897-906
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• 2005

The purpose of this research is to verify the strategic fitness and relevance of the distribution park for a hub port in Northeast Asia and to find a method to be a hub-port with a competitive edge. The strategic factor of distribution park development are policy, methodology and promotion method So these factors are analysed by structural equation model. The essential results of the research show that distribution park should be actually developed to produce value-added and to be port cluster.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.57 no.11
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• pp.2108-2116
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• 2008

The paper concerns Fuzzy C-Means clustering based Radial Basis Function neural networks (FCM-RBFNN) and the optimization of the network is carried out by means of Particle Swarm Optimization(PSO). FCM-RBFNN is the extended architecture of Radial Basis Function Neural Network(RBFNN). In the proposed network, the membership functions of the premise part of fuzzy rules do not assume any explicit functional forms such as Gaussian, ellipsoidal, triangular, etc., so its resulting fitness values directly rely on the computation of the relevant distance between data points by means of FCM. Also, as the consequent part of fuzzy rules extracted by the FCM - RBFNN model, the order of four types of polynomials can be considered such as constant, linear, quadratic and modified quadratic. Weighted Least Square Estimator(WLSE) are used to estimates the coefficients of polynomial. Since the performance of FCM-RBFNN is affected by some parameters of FCM-RBFNN such as a specific subset of input variables, fuzzification coefficient of FCM, the number of rules and the order of polynomials of consequent part of fuzzy rule, we need the structural as well as parametric optimization of the network. In this study, the PSO is exploited to carry out the structural as well as parametric optimization of FCM-RBFNN. Moreover The proposed model is demonstrated with the use of numerical example and gas furnace data set.

• Journal of Integrative Natural Science
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• v.8 no.4
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• pp.273-284
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• 2015

Chemoattractant Receptor Homologous molecule expressed on Th2 cells (CRTh2) is a chemoattractant receptor with seven transmembrane helices targeted for inflammatory diseases such as asthma and allergic rhinitis. In this study, pharmacophore based Comparative Molecular Similarity Indices Analysis (CoMSIA) were performed on the series of 2-(2-(benzylthio)-1H-benzo[d]imidazol-1-yl) acetic acids derivatives. Initially, GASP module was used for generation of pharmacophore models using five highly active compounds from the dataset. Among the generated pharmacophores, the best pharmacophore model was selected based on fitness score and was used as template for the alignment of compounds which was used for CoMSIA analysis. The best predictions were obtained utilizing steric, hydrophobic and H-bond acceptor parameters showing a $q^2$=0.559 and $r^2$=0.730. 15 test set compounds was used to investigate the predictive ability of the CoMSIA model. Contour maps suggested that presence of bulky substituents and H-bond acceptor atoms at $5^{th}$ position of benzene ring will increase the activity of the compounds. The results obtained from this study will be useful to design more potent CRTh2 antagonists.

• Journal of Fisheries and Marine Sciences Education
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• v.27 no.1
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• pp.230-242
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• 2015

The purpose of this study is to propose, firstly, the definition of marine health tourism and empirically to analyse the effect of benefit sought and brand equity on visit intention of destination as marine health tourism. This study utilizes the PLS-SEM method in order to measure the overall model fitness level and statistical significance of all paths in proposed research model. As a result of the analysis, benefit sought factor like nature has a highest positive effect on brand equity(image and perceived quality) and also, on visit intention via brand equity. Specially, this study measures the non-linear of all the paths and shows the statistical significance that the more high health factor as benefit sought is, the preference for quality brands is more steeply. In addition, the measurement of the moderating effect of gender variables shows that female is the most sensitive than male on the path from health benefit sought to brand quality among all the paths. However, the definition of marine health tourism in this study is proposed according to the characteristics of a particular area. In this vein, the definition is needed to generalize more through follow-up study.

• Journal of Korean Academy of Nursing Administration
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• v.21 no.4
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• pp.366-374
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• 2015

Purpose: This study was designed to identify a path model that anticipates the interpersonal competence of nurses by anticipating factors that explain interpersonal competence within an organization, and analyzing the effects of these factors. A hypothetical model was formulated based on a literature review of interpersonal competence. For the study, influential factors were divided into two variables: exogenous variables including communication style, coaching leadership, and social support, and endogenous variables of self-efficacy, job satisfaction, and organizational commitment. Methods: The sample included 202 hospital nurses. Data were collected through questionnaires and analyzed using SPSS and AMOS. Results: The overall fitness was good ($x^2=74.707$, p<.001), d.f=19, $x^2/df=3.932$, GFI=.940, AGFI=.826, RMR=.009). Social support, self-efficacy, horizontal communication and organizational commitment directly affected the interpersonal competence of the nurses, and informal type of communication, horizontal, upward communication and coaching leadership indirectly effected the interpersonal competence of the nurses. Horizontal communication, social support, self-efficacy, and organizational commitment explained 46.5% of the variance in interpersonal competence of nurses. Conclusion: Based on the study results, nurses in hospitals need informal types of communication, horizontal, upward communication and coaching leadership to increase their interpersonal competence.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• v.29 no.1
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• pp.465-470
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• 2005

The purpose of this research is to verify the strategic fitness and relevance of the distribution park for hub port in Northeast Asia and to find a method to be a hub-port with a competitive edge. The Strategic factor of distribution park development are policy, methodology and promotion method. So these factors are analysed by structural equation model. The essential results of the research show that distribution park should be actually developed to product value-added and connected to industry park to be port cluster.

• Journal of the Korean Society of Costume
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• v.55 no.5 s.95
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• pp.55-64
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• 2005

The concern with three-dimensional measurement has been growing in recent years. And over the last few years, several studies have been made on three-dimensional measurement. Some of the studies using a three-dimensional measurement have focused on type of form of human body and evaluation of fitness. But there has been no study about applications of three-dimensional measurement system for shape analysis. So, the purpose of this study was to investigate about application of three-dimensional mea-surement system lot shape analysis. The instrument and tools for three-dimensional measurement was Whole Body 3D scanner(model name: Exyma-WBS2H). Analysis program used in experiment is Rapid Form 2004 PPI (INUS technology, Int, Korea). The following results were obtained; 1. The point data using three-dimensional measurement system built 3D model. 2. The three-dimensional data were used to analyze length and curvature of shape. 3. The shape using three-dimensional measurement system could be used in variety field.