• Journal of applied mathematics & informatics
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• v.5 no.2
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• pp.489-498
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• 1998

The influence of observations the on the goodness-of-fit test in maximum likelihood factor analysis is investigated by using the local influence method. under an appropriate perturbation the test statistic forms a surface. One of main diagnostics is the maximum slope of the perturbed surface the other is the direction vector cor-responding to the curvature. These influence measures provide the information about jointly influence measures provide the information about jointly influential observations as well as individ-ually influential observations.

• Nuclear Engineering and Technology
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• v.54 no.11
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• pp.4195-4208
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• 2022

In this study, operator habitability was numerically evaluated in the event of a fire at the main control bench board (MCB) in a reference main control room (MCR). It was investigated if evacuation variables including hot gas layer temperature (HGLT), heat flux (HF), and optical density (OD) at 1.8 m from the MCR floor exceed the reference evacuation criteria provided in NUREG/CR-6850. For a fire model validation, the simulation results of the reference MCR were compared with existing experimental results on the same reference MCR. In the simulation, various input parameters were applied to the MCB panel fire scenario: MCR height, peak heat release rate (HRR) of a panel, number of panels where fire propagation occurs, fire propagation time, door open/close conditions, and mechanical ventilation operation. A specialized-average HRR (SAHRR) concept was newly devised to comprehensively investigate how the various input parameters affect the operator's habitability. Peak values of the evacuation variables normalized by evacuation criteria of NUREG/CR-6850 were well-correlated as the power function of the SAHRR for the various input parameters. In addition, the evacuation time map was newly utilized to investigate how the evacuation time for different SAHRR was affected by changing the various input parameters. In the previous studies, it was found that the OD is the most dominant variable to determine the MCR evacuation time. In this study, however, the evacuation time map showed that the HF is the most dominant factor at the condition of without-mechanical ventilation for the MCR with a partially-open false ceiling, but the OD is the most dominant factor for all the other conditions. Therefore, the method using the SAHRR and the evacuation time map was very useful to effectively and comprehensively evaluate the operator habitability for the various input parameters in the event of MCB fires for the reference MCR.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.14 no.5
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• pp.370-376
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• 2004

The overall aim of this paper is to determine coupling loss factor of welding point between shell and cylinder using loss factor and structural loss factor. For this purpose, two kinds of loss factor were adopted. One is loss factor of each sub structure, another is structural loss factor based on the complex welded or assembled structure. Using these two parameters, it ispossible to derive the coupling loss factor which represent characteristic condition of SEA theory. Coupling loss factor of conjunction in complex structure was expressed as power balance equation. The derived equation for a coupling loss factor has been simplified on the assumption of one way (uni-directional) power flow between multi-sub structures. Using these conditions, it is possible to find the equation of coupling loss factor expressed as above two loss factors. To check the effectiveness of above equation, this paper used two-stage application. The first approach was application between simple cylinder and shell. The next was adopted rotary compressor. Rotary compressor has three main conjunctions between shell and internal vibration part. This equation was applied to find out the optimum welding point with respect to reduce the noise propagation. It shows the effective tool to evaluate the coupling loss factor in complex structure

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2003.05a
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• pp.969-972
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• 2003

The overall aim of this paper is to determine coupling loss factor of welding point between shell and cylinder using loss factor and structural loss factor. For this purpose, two kinds of loss factor were adopted. One is loss factor of each sub structure, another is structural loss factor based on the complex welded or assembled structure. Using these two parameters, it is possible to derive the coupling loss factor which represent characteristic condition of SEA theory. Coupling loss factor of conjunction in complex structure was expressed as power balance equation. The derived equation for a coupling loss factor has been simplified on the assumption of one way(nl- directional) power flow between multi-sub structures. Using these conditions, it is possible to find the equation of coupling loss factor expressed as above two loss factors. To check the effectiveness of above equation, this paper used two stage application. The first approach was application between simple cylinder and shell. The next was adopted rotary compressor. Rotary compressor has three main conjunctions between shell and internal vibration part. This equation was applied to find out the optimum welding Point with respect to reduce the noise propagation. It shows the effective tool to evaluate the coupling loss factor in complex structure

• Journal of the Korean housing association
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• v.19 no.5
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• pp.37-46
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• 2008

The purpose of this study is to derive and adapt the Valuation Factor of urban regeneration scientifically and synthetically, which is the basis of developing a rational plan for urban revitalization. For this, we have selected 37 factors relating to urban regeneration as outlined in preceding studies and inquiry about importance of factors. we analysed he Valuation factors influencing he importance of urban revitalization through a questionnaire which was completed by inhabitants and expert groups in Gwangju Metropolitan City. From he results of he Factor analysis using SPSSWIN(VER.14.0), it was found that the factors which influence the importance of urban regeneration are Environment, Function, Resources and Policy Factors. Environment Factor comprises amenity, culture, beauty and convenience, The while the Function Factor comprises interchange, information, complexity and security. This classification has credibility because of the high factor loading through the Varimax Factor Analysis and is due to a high Cronbach's coefficient. There is a strong correlation between the classified factors through correlation analysis. Finally, through AMOS (Analysis of Moment Structure) 16.0 it was found that the upper classification is credible because main suitability index confirms recommending an admission standard.

• Transactions of the Korean Society of Automotive Engineers
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• v.17 no.1
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• pp.80-86
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• 2009

Main bearing cap is one of the essential structural elements in internal combustion engine. Main bearing cap guides and holds the crankshaft, withstanding the full combustion and inertia loads of the engine. A seamless design methodology using FEA has been proposed to produce a reliable design of main bearing cap. A Levy's thick cylinder model was applied to calculate the contact pressure between bearing shell and housing bore. A calculated contact pressure at housing bore is within the allowed limit comparing with that from bearing shell model. An adequate FEA model was suggested to obtain reliable solutions for the durability of main bearing cap. 3D global model consists of engine bulkhead, main bearing cap, and bolts. Sub-model consisting of cap and part of bolts is used to get detailed solution of main bearing cap. A very careful contact modeling practice is needed to resolve the convergence problems frequently encountering during combined geometric and material non-linear problems. A proposed methodology has been applied to the main bearing cap model successfully and obtained reliable stress results and fatigue safety factors.

• Journal of Information Processing Systems
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• v.2 no.3 s.4
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• pp.178-182
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• 2006

Children exhibit different behaviors, skills, and motivations. The main aim of this research was to investigate children's sensibility factors for icons, and to look for the best typeface for application to Web-Based Instruction (WBI) for e-Learning. Three types of icons were used to assess children's sensibilities toward metaphors: text-image, representational, and spatial mapping. Through the factor analysis, we found that children exhibited more diverse reactions to the text-image and representational types of icons than to the spatial mapping type of icons. Children commonly showedn higher sensibilities to the aesthetic-factor than to the familiarity-factor or the brevity-factor. In addition, we propose a collaborative-typeface system, which recommends the best typeface for children regarding the readability and aesthetic factor in WBI. Based on these results, we venture some suggestions on icon design and typeface selection for e-Learning.

• The Transactions of the Korean Institute of Electrical Engineers B
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• v.50 no.8
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• pp.392-401
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• 2001

This paper presents the single-stage high power factor AC to DC converter operated in active-clamp mode. The proposed converter is added active-clamping circuit to boost-flyback single-stage power factor corrected power supply. The active-clamping circuit limits voltage spikes, recycles the energy trapped in the leakage inductance, and provides a mechanism for achieving soft switching of the electronic switches to reduce the switching loss. The auxiliary switch of active-clamping circuit uses the same control and driver circuit as the main switch to reduce the additional cost and size. To verify the performance of the proposed converter, a 100W converter has been designed. The proposed converter gives good power factor correction, low line current harmonic distortions, and tight output voltage regulation, as used unity power factor.

• Korea Journal of Hospital Management
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• v.1 no.1
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• pp.136-153
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• 1996

The purpose of this study is to identify the factors hindering hospital reengineering project in one university hospital. The data was collected by the self-administered Questionnaire to 288 members of the hospital in Pusan on April 5-18, 1996. This study took some statistical methodologies, such as descriptive analysis, factor analysis and logit model analysis. The results were as follows; First, in the descriptive analysis for whether the hospital reengineering named RUSH94 was a success or not, the subjects judged that it was not successful and regarded their fable mutual communication as the main factor. Second, in the reason of failure at the reengineering project, the group who thought that the failure factor was the lack of mutual consensus checked the scores of the first factor produced from the factor analysis.

• Fashion & Textile Research Journal
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• v.4 no.1
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• pp.11-18
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• 2002

The purpose of this study was to investigate the characteristic and composition factor of Japanese costume design. The stimulus were 25 contemporary costume design which represented the traditional image of Japanese. The main survey of questionary consisted of their evaluation of the Japanese costume image by 26 semantic differential bipolar scales and the subjects were 99 female students majoring in clothing and textiles. The data were analyzed by Factor analysis, Multidimensional Scaling Method and Regression Analysis. The major findings were as follows. As a result of design analysis, contemporary Japanese costume design which represented the traditional image had traditional form, color, texture, pattern, etc. Through factor analysis about Japanese costume image 7 factors were identified; Attractiveness, Attention, Cool and warm, Neatness, Activeness, Maturity, Classics. According to image positioning, Japanese costume design was classified by simple-decorative, soft-hard. As the result of regression analysis, The preference of Japanese costume image was related to attractive factor.