• Applied Chemistry for Engineering
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• v.17 no.3
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• pp.296-302
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• 2006

The kinetics of the thermal-oxidative decomposition of waste polyurethane (PU) according to oxygen concentration has been studied using a non-isothermal thermogravimetric technique at several heating rates from 10 to $50^{\circ}C/min$. A kinetic model accounting for the effects of the oxygen concentration by the differential and integral method based on Arrhenius equation was proposed to describe the thermal-oxidative decomposition of waste PU. To obtain the information on the kinetic parameters such as activation energy, reaction order, and pre-exponential factor, the thermogravimetric analysis curves and its derivatives have been analyzed using the kinetic analysis method proposed in this work. From this work, it was found that reaction orders for oxygen concentration had a negative sign, and activation energy decreased as the oxygen concentration increased. It was also found that the kinetic parameters obtained from the integral method using the single heating rate experiments varied with heating rates. Therefore, it is thought that the differential method using the multiple heating rate experiments more effectively represents the thermal-oxidative decomposition of waste polyurethane.

• Journal of the Korean Society of Clothing and Textiles
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• v.26 no.11
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• pp.1615-1626
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• 2002

The purpose of this study was to investigate the effect of shopping orientation, and service quality and satisfaction on impulsive buying behavior in two types of apparel store. The sample consisted of 616 females aged 20-30 who were shopping at department stores and shopping malls in Busan. Data were analyzed with factor analysis, t-test, cross analysis and path analysis. The results showed that consumers of department stores showed more strongly convenient orientation than those of the shopping mall, consumers of the shopping mall showed more strongly recreational orientation and practical orientation than those of the department. Stores services of the department were perceived better than that of the shopping mall in promotional services, salespersons' services and environmental services. But it didn't show any differences between store types in product services. Consumers 'satisfaction with the service was greater in department stores than the shopping mall. But it didn't show any difference between apparel store types in the impulsive buying behaviors. Impulsive buying behavior of department store shoppers is directly affected by a shopper' shopping orientation as well as store service quality perceived by shoppers rather than a shopper' satisfaction. The service quality does not have directly related to consumers’ service satisfaction. The causal relationships of impulsive buying behaviors showed similarity in shopping malls and department stores. The perceived quality and satisfaction with store service were higher at department store than shopping malls. In impulse buying behavior of a department store was directly affected by a shopper' shopping orientation as well as store service quality perceived by shoppers rather than a shopper’ store service satisfaction.

• Child Health Nursing Research
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• v.23 no.2
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• pp.158-167
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• 2017

Purpose: The purpose of this study was to investigate the ecological factors influencing school adjustment of adolescents from low-income families. Methods: Secondary data analysis was performed using data of 1,321 low-income adolescents in 123 regions found on the Survey on Service Satisfaction with Community Child Care Center. Results: The results of multi-level analysis identified the factors influencing school adjustment of low-income adolescents as follows: individual-level factors were gender, grade in school, and emotional problem; an interpersonal-level factor was family structure; organizational-level factors were length of time attending center and satisfaction with the service of the center; community-level factors were region and perception of community. Conclusion: The results suggest that low-income adolescents' adjustment to school is influenced not only by individual factors but also by diverse environmental factors. Community factors suggest that more education support systems and leisure facilities for adolescents need to be built in small and medium cities. Strategies to enhance positive perception of community are also needed for this population. Further, it is necessary to develop multi-level interventions to improve the school adjustment of adolescents from vulnerable social groups.

• Korean Institute of Interior Design Journal
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• v.15 no.6 s.59
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• pp.205-212
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• 2006

The premise of this study is that an ultimate objective in planning an exhibition space is spectators' experiences shaped by a result of their first-hand experiences and responses within an exhibition space, and this result can be recognized in the spectators' movement. Thus, the sign system that can directly affects viewers' main line of flow and movement patterns was examined vis--vis a mutually complementary relation in a triangular composition with the structure of exhibition space and the exhibition contents. Based on the findings, predictive values before and after a complementary application of the sign system to the structure of exhibition space was analyzed and its validity was assessed. The results of this research analysis were drawn as follows. It was shown that an understanding of the locations of direction signs and the degree of recognition can function as an important factor to predict viewers' movement, along with an understanding of topological characteristics of an exhibition space. In terms of the connection and disconnection of space units that form the space structure, it suggests that the distribution of signs and the degree of recognition can adjust the degree of connection and disconnection. Even though exhibition spaces for research subjects were selected from a relatively large number of museums, but the research was limited with a focus on the structure of exhibition space and sign systems. Thus, it is proposed that future studies should be conducted by including varieties of exhibition and environmental factors.

• Genomics & Informatics
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• v.6 no.3
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• pp.110-116
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• 2008

Blood pressure refers to the force exerted by circulating blood on the walls of blood vessels, and chronical elevation of blood pressure is known as hypertension. Although hypertension is affected by genetic and environmental factors, the genetic background of hypertension is not fully understood. One of the candidate genetic factors, Prostaglandin-endoperoxide synthase 2 (PTGS2), is a membrane-bound enzyme, catalyzing the conversion of arachidonic acid to prostaglandin, and recently SNPs of PTGS2 gene was associated with hypertension in Japanese population. Therefore the association of PTGS2 polymorphisms was investigated with blood pressure in healthy Korean subjects, 470 unrelated individuals randomly selected from Ansung and Ansan cohorts. The 25 SNPs of PTGS2 gene were identified by the sequencing analysis of 24 Korean samples. Among identified polymorphisms, three SNPs (rs689466, -1329A>G; rs5275, +6365T>C; rs4648308, +8806G> A) were selected for further association analysis, and rs689466 located in promoter region was associated with blood pressure as well as triglyceride level in the blood. By in silico analysis, rs689466 locates in v-Myb transcription factor binding site, and the v-Myb site disappears when the SNP is changed from A to G nucleotide. Individuals with A/G and G/G genotype in rs689466 have higher blood pressure than those with A/A genotype, and the regression p-value is 0.008 for systolic and 0.004 for diastolic blood pressure. In summary, the PTGS2 polymorphism (rs689466) is associated with blood pressure in Asian populations based on this and Japanese studies, shedding light on it as a genetic risk marker of hypertension.

• Steel and Composite Structures
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• v.22 no.3
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• pp.497-520
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• 2016

The confined concrete stress-strain curves utilised in computational models of concrete-filled steel tubular (CFST) columns can have a significant influence on the accuracy of the predicted behaviour. A generic model is proposed for predicting the stress-strain behaviour of confined concrete in short circular, elliptical and octagonal CFST columns subjected to axial compression. The finite element (FE) analysis is carried out to simulate the concrete confining pressure in short circular, elliptical and octagonal CFST columns. The concrete confining pressure relies on the geometric and material parameters of CFST columns. The post-peak behaviour of the concrete stress-strain curve is determined using independent existing experimental results. The strength reduction factor is derived for predicting the descending part of the confined concrete behaviour. The fibre element model is developed for the analysis of circular, elliptical and octagonal CFST short columns under axial loading. The FE model and fibre element model accounting for the proposed concrete confined model is verified by comparing the computed results with experimental results. The ultimate axial strengths and complete axial load-strain curves obtained from the FE model and fibre element model agree reasonably well with experimental results. Parametric studies have been carried out to examine the effects of important parameters on the compressive behaviour of short circular, elliptical and octagonal CFST columns. The design model proposed by Liang and Fragomeni (2009) for short circular, elliptical and octagonal CFST columns is validated by comparing the predicted results with experimental results.

• Journal of Wetlands Research
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• v.17 no.4
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• pp.421-427
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• 2015

In ASM model, organic matters are classified according to their characteristics and general classification into COD and BOD cannot satisfy conditions required by ASM. In this study, it was performed to study classification of organic matters required by ASM on the basis of microorganisms' respiration rate subject to wastewater and sludge treatment. As results of analysis of the organic matter's appearance, it was found that there were some differences in composition of organic matters between wastewaters. It is considered that it is an important characteristic of wastewater that should be understood in treating wastewater in each process. Therefore, it is considered that appearance of organic matters in each wastewater identified by this study will be used as important basic data for operation of municipal wastewater treatment plant. It was identified that SS was an important factor affecting nitrification through organic matter and ammonium nitrogen change analysis according to reaction time in the nitrification. It is considered that the nitrification has close relationship with choice of optimal retention time.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.63 no.10
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• pp.1377-1383
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• 2014

This paper deals with eddy current loss of magnetic coupling with radial permanent magnet (PM) using analytical method such as a space harmonic method. Superposition of two kinds analysis model is used to analyze eddy current loss induced in inner PM and outer PM of magnetic coupling. When the eddy current is induced, the environmental temperature increases, and the permanent magnet(PM) characteristics are degraded because the performance of PM is greatly influenced by temperature rise. Hence, the calculation of eddy current loss becomes an important factor in the magnetic coupling. In order to analyze eddy current loss, first, on the basis of the magnetic vector potential and two-dimensional(2-D) polar-coordinate system, the magnetic field solutions of the radial magnetized PM are obtained. And we obtain the analytical solutions for the eddy current density produced by permanent magnet. Lastly, analytical solutions for eddy current loss are derived by using equivalent, electrical resistance calculated from magnet volume and analytical solution for eddy current density. This analytical results are validated by comparing with the 2-D finite element analysis (FEA).

• Journal of agriculture & life science
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• v.45 no.3
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• pp.1-7
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• 2011

This study was carried out to provide the basic information for effective preservation and management of forest community of Nari basin in Ulleung Island. Forest community in Nari basin was classified into Fagus engleriana community, Sorbus amurensis community, Pinus densiflora community, Celtis jessoensis community and Alnus maximowiczii community. As the result of DCCA ordination analysis, sea level among environmental factors had high correlation with community distribution. Fagus engleriana community and Sorbus amurensis community correlated highly with aspect, Na content, and C/N ratio. There was a high correlation between Celtis jessoensis community and the content of Ca and K. Alnus maximowiczii community was distributed in site where CEC content is high. Pinus densiflora community was distributed in site where the content of Ca and CEC is high.

• Journal of the Korea Society of Computer and Information
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• v.26 no.5
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• pp.31-38
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• 2021

This study empirically investigated the user's experience with based on the Technology Acceptance Model. According to the frequency analysis results, the usability for learning was evaluated relatively higher than that for appreciation from the perspective of perceived usefulness and the technical factors such as graphics and modeling raised the issue for the quality improvement. According to the results of the correlation analysis, the usability for learning correlated with the degree of satisfaction. In addition, all detailed factors of perceived ease of use positively influenced on the degree of satisfaction and the impact of the environmental factor on the degree of satisfaction was greatest. The degree of satisfaction with the VR application significantly correlated with the degree of immersion and behavioral intention to the VR application. Therefore, this study proved the suitability for the Technology Acceptance Model as a tool for evaluating a VR application.