• Journal of the Korean Society of Clothing and Textiles
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• v.26 no.11
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• pp.1605-1614
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• 2002

The purpose of this study was to identify the consumers who use the level of price as the indicator of the product quality. In order to implement the purpose of this study, Jeans market had been segmented by the mixture regression model, and price response function was calibrated for each segment. Based on the types of price response function, segments were allocated into one of two groups; the group using the level of price as the quality indicator or the group not using the level of price as that. Then, characteristics of both groups were compared in terms of product attributes and demographic variables. Data were co]looted from the sample of the 23o undergraduate and graduate students in Seoul. For the data analysis, mixture regression model, conjoint analysis, and t-test were used. As a result, jeans market was divided into 5 segments. Segment 1,2,3 were allocated into the group not using the level of price as the quality indicator while segment 4,5 were done into the other group. Significant differences existed between two groups in product attributes, not in demographic variables. Mixture model and conjoint analysis were proved to be an effective set of tools in market segmentation.

• Journal of Korean Society for Quality Management
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• v.44 no.4
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• pp.799-811
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• 2016

Purpose: The conjoint analyst in marketing are interested in detecting whether there exist synergy or antagonistic effects between two attributes. In the cases where attributes have two or three levels, we research on the design of survey questionnaire to estimate all the main effect and as many two factor interaction effects as possible. Methods: We consider the balanced incomplete block (BIB) mixed level factorial design $2^f{\times}3^g$ or fractional factorial design. To reduce the number of questions in a questionnaire, we propose the balanced incomplete block mixed level design with minimum aberration which is generated by implementing proc factex in SAS. Also, we propose using two or three level BIB factorial design instead of mixed level designs by transforming three level attributes into two attributes of two levels and two level attribute into three level attribute by using dummy level technique. Results: We propose three methods for designing survey questionnaire where the block and design generators are found with practical number of questions in a questionnaire. By analyzing all the respondents survey data generated by the simulation study, we find the proper model and do the concepts optimization. Conclusion: The proposed methods of designing survey questionnaires seem to perform well in the sense that the proper model, and then the optimal concept is found in a case study where all the respondents survey data are generated by the simulation study.

• Journal of Korean Society for Quality Management
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• v.30 no.4
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• pp.154-163
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• 2002

This study tries to analyze how TPM works in domestic manufacturing industry by estimating two-stage model. First stage tests the effects of five TPM-factor variables (TFV : (1) Small group activity & Autonomous maintenance, (2) Education & Training, (3) Planned maintenance, (4) improving effectiveness of each piece of facility (5) Safety & Environment) to two TPM-performance variables. Second stage tests how two TPVs affect the industry's productivity level. By combining these two stages, this study uses a model to explain how TPM, represented by TFVs, works to improve productivity via TPVs. Multivariate and univariate regression and correlation analyses were peformed. It is shown that five TFVs works in two different ways to improve the industry's productivity level. In the second stage, overall equipment effectiveness has relatively more significant effects to the productivity level.

• The Mathematical Education
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• v.51 no.4
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• pp.351-375
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• 2012

This research is a case study of the changes of students's problem solving ability and affective characteristics when we apply to general students MG-CPS model which is creative problem solving model for gifted students. MG-CPS model which was developed by Kim and Lee(2008) is a problem solving model with 7-steps. For this study, we selected 7 first grade students from girl's high school in Seoul. They consisted of three high level students, two middle level students, and two low level students and then we applied MG-CPS model to these 7 students for 5 weeks. From the study results, we found that most students's describing ability in problem understanding and problem solving process were improved. Also we observed that high level students had improvements in overall problem solving ability, middle level students in problem understanding ability and guideline planning ability, and that low level students had improvements in the problem understanding ability. In affective characteristics, there were no significant changes in high and middle level classes but in low level class students showed some progress in all 6 factors of affective characteristics. In particular, we knew that the cause of such positive changes comes from the effects of information collection step and presenting step of MG-CPS model.

• Smart Structures and Systems
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• v.24 no.6
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• pp.793-802
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• 2019

The centrifuge model test is usually used for two-dimensional deformation and instability study of the soil slopes. As a typical loose slope, the municipal solid waste (MSW) landfill is easy to slide with large deformation, under high water levels or large earthquakes. A series of centrifuge model tests of landfill slide induced by rising water level and earthquake were carried out. The particle image velocimetry (PIV), laser displacement transducer (LDT) and marker tracer (MT) methods were used to measure the deformation of the landfill under different centrifugal accelerations, water levels and earthquake magnitudes. The PIV method realized the observation of continuous deformation of the landfill model, and its results were consistent with those by LDT, which had higher precision than the MT method. The deformation of the landfill was mainly vertically downward and increased linearly with the rising centrifugal acceleration. When the water level rose, the horizontal deformation of the landfill developed gradually due to the seepage, and a global slide surface formed when the critical water level was reached. The seismic deformation of the landfill was mainly vertical at a low water level, but significant horizontal deformation occurred under a high water level. The results of the tests and analyses verified the applicability of PIV in the two-dimensional deformation measurement in the centrifuge model tests of the MSW landfill, and provide an important basis for revealing the instability mechanism of landfills under extreme hydraulic and seismic conditions.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.11 no.2
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• pp.127-133
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• 1999

The MOSU model, a depth-averaged two-dimensional sediment transport model, is applied to simulate the bed level changes before and after dock construction in Daemyung site. The model is a semi¬coupled finite difference model that can be applied to a river, a reservoir, a lake, estuaries, or coastal regions, The model is able to simulate the transport of fine sand, silt, and clay. The model parameters are estimated by qualitative calibration. A prediction result of the numerical model shows that the bed level changes due to dock construction are little.

• Journal of Industrial Technology
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• v.27 no.A
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• pp.85-94
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• 2007

This study, regarding curved channel, was performed to compare and analyze hydraulic characteristics and the speed of water and water level for left bank and right bank through hydraulic model experiments and numerical analysis. Real channels that had characteristics of curved channel were selected as objectives. In order to easily operate one and two dimensional numerical analysis and comparison for total 2.4Km model channel, measuring point was set up as 200m. HEC-RAS model was applied as one dimensional numerical analysis program and SMS model was used as two dimensional numerical analysis program. In respect of speed of water, the average speed of water for right bank recorded 8.33m/s in a model experiment and 3.08m/s, 8.57m/s were average speed of water for right bank in one dimensional and two dimensional numerical analysis. The average speed of water of two dimensional numerical analysis was quite similar to that of model experiments. Also, as for water level, maximum observational errors between one and two dimensional numerical analysis for right and left bank of model experiments were 0.66m, 0.84m and 0.28m, 0.48m for each. It was found that two dimensional numerical analysis had a similar result to hydraulic model experiments. Accordingly, from the result of this study, two dimensional numerical analysis should be used rather than one dimensional numerical analysis, when numerical analysis for curved channel is conducted.

• 유체기계공업학회:학술대회논문집
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• 1998.12a
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• pp.33-41
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• 1998

In this study, the performance prediction programs for centrifugal pumps are developed. To estimate the losses in the centrifugal pump impellers, two-zone model and TEIS(two elements in series) model are applied to the program. The basic concept of two zone model considers the primary zone that is an isentropic core flow and the secondary zone that is non-isentropic region at the impeller exit. The flows through two different zones mixed out at the impeller exit and the mixing process occurs with an increase in entropy, a decrease in total pressure. The level of the core flow diffusion in a impeller was calculated using TEIS(two elements in series) model. The effects of various parameters which are used in this program on the prediction of head and efficiency are discussed. The correlation curves to select the effectiveness of the primitive TEIS model were suggested according to the specific speed of the centrifugal pumps.

• The KSFM Journal of Fluid Machinery
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• v.2 no.1 s.2
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• pp.56-63
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• 1999

In this study, the performance prediction programs for centrifugal pumps are developed. To estimate the losses in the centrifugal pump impellers, a two-zone model and TEIS(two elements in series) model are applied to the program. The basic concept of a two zone model considers the primary zone that is an isentropic core flow and the secondary zone that has a non-isentropic region at the impeller exit. The flow goes through two different zones and is mixed out at the impeller exit and the mixing process occurs with an increase in entropy, a decrease in total pressure. The level of the core flow diffusion in an impeller was calculated using TEIS(two elements in series) model. The effects of various parameters which are used in this program on the prediction of head and efficiency are discussed. The correlation curves used to select the effectiveness of the primitive TEIS model were suggested according to the specific speed of the centrifugal pumps.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2008.11a
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• pp.441-446
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• 2008

The source transfer receiver model ('Source $\times$ Transfer = Response' model) which is widely used by NVH development process of vehicle/transport/machinery to analyze effectively and manage efficiently the structural dynamic behavior is also applicable to construction structure. If the evaluation assessment of the vibration level does not meet the target level, there are two methods, one is source treatment or replacement and the other is the reduction treatment on the transfer structure. In case of source treatment, it is done by source supplier and so, the latter is more practical method to reduce the vibration level. In this study, in order to get the accurate Transfer FE model(floor structure FE model), Experimental modal analysis of part of floor structure and FEM modal analysis of full floor structure are performed, then updating of FE model is performed after correlation analysis between these two results and finally, the modal model and FRF are compared between FE and Experimental results.