• Proceedings of the KIPE Conference
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• 2015.11a
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• pp.209-210
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• 2015

This paper presents a new model predictive control method without the effect of a weighting factor in order to reduce common-mode voltage (CMV) for a three-phase voltage source inverter (VSI). By utilizing two active states with same dwell time during a sampling period instead of one state used in conventional method, the proposed method can reduce the CMV of VSI without the weighting factor. Simulation is carried out to verify the effectiveness of the proposed predictive control method with the aid of PSIM software.

• International conference on construction engineering and project management
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• 2013.01a
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• pp.419-425
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• 2013

Recently AEC industry has required construction automation according to becoming large and complex. Thus BIM-based construction project is increased and used in whole fields of AEC industry. Quantity take-off and estimation fields are important factor for decision-making in conceptual and schematic design stages of construction projects. The purpose of this study improves reliability of the estimation through QTO based on Open BIM. Scope and method to apply QTO is to select conceptual design stage through LoD(Level of Detail) in AEC field and to extract information from BIM model through analysis of IFC structure. This study proceeds three step to make BIM model and check the model quality and calculate QTO. The methodology of QTO using IFC is to verify of result in this study and expects utilizing in design stage of construction projects. The result from this study is expected to decrease the risk factor and time of estimation in the project early phase through improving reliability of schematic estimation.

• Journal of the Korean Society of Clothing and Textiles
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• v.35 no.10
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• pp.1139-1149
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• 2011

This study tested the validity of a three-factor model of the centrality of visual product aesthetics developed by Bloch, Brunel, and Arnold (2003) and explored the relationships between the centrality of visual product aesthetics and the relevant constructs. It was hypothesized that the path relationships including innovativeness and consumer independent judgment making are relevant constructs of the centrality of visual product aesthetics. Data were gathered by surveying university students in the Seoul metropolitan area (using convenience sampling) and 322 questionnaires were used in the statistical analysis. Correlation analysis, factor analysis, and regression analysis were conducted to analyze the data. The findings show the validity of the three factors (value, acumen, and response intensity) of the centrality of visual product aesthetics. Tests of the hypothesized path show that innovativeness influences the centrality of visual product aesthetics both directly and indirectly through consumer independent judgment making. Innovativeness positively influenced consumer independent judgment making and the three factors of the centrality of visual product aesthetics, whereas consumer independent judgment negatively influences the response intensity factor of the centrality of visual product aesthetics. The implications of these findings and suggestions for future study are also discussed.

• Journal of Korean society of Dental Hygiene
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• v.20 no.6
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• pp.913-924
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• 2020

Objectives: This study was conducted to develop a dental hygienist's job satisfaction scale and to evaluate its validity and reliability. Methods: A total of 34 preliminary questions were composed based on the components commonly defined in previous studies and in-depth interviews. Results: The results of the study were practice activity, professional satisfaction, income, working conditions, patient relations, and co-worker relations using the exploratory factor analysis. Goodness of fit of the model assessed using confirmatory factor analysis generally met the criteria. On verification of the internal consistency, the Cronbach's alpha for the factors were as follows: 0.821 for practice activity, 0.822 for professional satisfaction, 0.847 for income, 0.765 for working condition, 0.743 for patient relations, and 0.747 for co-worker relations, which implied that the measurement tool was reliable. Through exploratory and confirmatory factor analyses, a total of 24 items for six factors: six items for practice activity factors, four items for professional satisfaction, three items for income, four items for working conditions, three items for patient relationships, and three items for coworker relations. Conclusions: Based on the aforementioned results, the validity and reliability of the dental hygienist's job satisfaction measurement tool were satisfactory. Thus, it may be used for assessing the job satisfaction of the dental hygienists in future.

• 한국데이터정보과학회:학술대회논문집
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• 2005.10a
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• pp.177-188
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• 2005

Association rule mining searches for interesting relationships among items in a given large data set. Association rules are frequently used by retail stores to assist in marketing, advertising, floor placement, and inventory control. There are three primary threshold measures in association rule; support and confidence and lift. In the case of appling real world to association rules, we have some difficulties in data interpretation because we obtain many rules. In this paper, we develop the model of association rules using latent variables for environmental survey data.

• Journal of the Korean Data and Information Science Society
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• v.17 no.1
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• pp.149-160
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• 2006

Association rule mining searches for interesting relationships among items in a given large data set. Association rules are frequently used by retail stores to assist in marketing, advertising, floor placement, and inventory control. There are three primary threshold measures in association rule; support and confidence and lift. In the case of appling real world to association rules, we have some difficulties in data interpretation because we obtain many rules. In this paper, we develop the model of association rules using latent variables for environmental survey data.

• Proceedings of the KSME Conference
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• 2008.11b
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• pp.2131-2136
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• 2008

The characteristics of heat transfer and pressure drop in an offset strip fin heat exchanger was studied with a steady-state three dimensional numerical model. Flow Reynolds number $Re_{dh}$ ranged from 10 to 3500 and Prandtl number Pr ranged from 0.7 to 50. The dimensionless performance factors, i.e. 'the pumping power factor F' and 'the heat transfer performance factor J' were analyzed and obtained a relationship between them. Finally, the prediction of F and J factors was generalized for different Prandtl numbers.

• Computers and Concrete
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• v.19 no.6
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• pp.725-736
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• 2017

This paper presents the two-, three-, and four-lane transverse reduction factor based on FEA method, probability theory, and the recently actual traffic flow data. A total of 72 composite girder bridges with various spans, number of lanes, loading mode, and bridge type are analyzed with time-varying static load FEA method by ANSYS, and the probability models of vehicle load effects at arbitrary-time point are developed. Based on these probability models, in accordance to the principle of the same exceeding probability, the multi-lane transverse reduction factor of these composite girder bridges and the relationship between the multi-lane transverse reduction factor and the span of bridge are determined. Finally, the multi-lane transverse reduction factor obtained is compared with those from AASHTO LRFD, BS5400, JTG D60 or Eurocode. The results show that the vehicle load effect at arbitrary-time point follows lognormal distribution. The two-, three-, and four-lane transverse reduction factors calculated by using FEA method and probability respectively range between 0.781 and 1.027, 0.616 and 0.795, 0.468 and 0.645. Furthermore, a correlation between the FEA and AASHTO LRFD, BS5400, JTG D60 or Eurocode transverse reduction factors is made for composite girder bridges. For the two-, three-, and four-lane bridge cases, the Eurocode code underestimated the FEA transverse reduction factors by 27%, 25% and 13%, respectively. This underestimation is more pronounced in short-span bridges. The AASHTO LRFD, BS5400 and JTG D60 codes overestimated the FEA transverse reduction factors. The FEA results highlight the importance of considering span length in determining the multi-lane transverse reduction factors when designing two-lane or more composite girder bridges. This paper will assist bridge engineers in quantifying the adjustment factors used in analyzing and designing multi-lane composite girder bridges.

• The Journal of Natural Sciences
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• v.13 no.1
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• pp.113-128
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• 2003

The purpose of his study was to investigate the effectiveness on clothing advertisement of three types of model, perception of model attributes by the clothing consumers, and difference in advertisement effectiveness according to perception of model attributes. Three types of advertisements for easy casual brand were selected, which are using celebrity, expert and general consumer models. The final analysis included 304 persons, who ranged from 16 to 25 in age. The statistics used analysis include ANOVA, Duncan's multiple range test, factor analysis and regression by the SPSS program. The result were as follow:1. The celebrity advertisement was the most effective type on all kinds of attitude changes (cognitive, emotional, and behavioral attitude changes) of consumers.2. The celebrity model received high scores on attractiveness and truthfulness; and the general consumer model received high scores on truthfulness and similarity.3. The amount of consumers attitude changes was different according to the perceptions of model attributes as well as the types of model.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.35 no.9
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• pp.1091-1097
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• 2011

The SGBEM-FEM alternating method has been known to be a very effective method for analyzing threedimensional cracks in a finite body. The accurate values of the stress intensity factor can be obtained for a general planar or nonplanar three-dimensional crack. In the existing method, eight-noded quadrilateral boundary elements are used to model a crack. In some cases, three-node triangle boundary elements are more convenient for the modeling of a crack with a general shape. In this study, a crack is modeled with three-noded triangular and seven-noded quadrilateral elements by using the advancing-front mesh generation method. The stress intensity factors are obtained for cracks with several shapes and the accuracy of results is examined.