• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.11 no.4
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• pp.31-36
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• 2001

A spin coater is a machine to coat wafer or LCD display with thin film. Vibration in the spin coater may be one of main troubles in the coating process. In this paper, we focus on the difference between two spin coaters. Vibration sources are identified by experimental approach and are compared to find the difference between the two spin coaters. Also, the particle concentration is observed by laser particle counter (LPC) for the two spin coaters, when the spin coaxers are working. It is also considered whether the defect rate is proportional to the particle concentration. The result shows that particle generation in the coating process is related to excessive vibration of the spin coater shaft and the particles influence the defect rate of the thin film product.

• International Journal of CAD/CAM
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• v.8 no.1
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• pp.11-20
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• 2009

The conventional methods of boundary-conformed 2D surfaces generation usually yield some problems. This paper deals with two boundary-conformed 2D surface generation methods, one conventional approach, the linear Coons method, and a new method, boundary-conformed interpolation. In this new method, unidirectional 2D surface has been generated using some of the geometric properties of the given boundary curves. A method of simultaneous displacement of the interpolated curves from the opposite boundaries has been adopted. The geometric properties considered for displacements include weighted combination of angle bisector and linear displacement vectors at all the data-points of the two opposite generating curves. The algorithm has one adjustable parameter that controls the characteristics of transformation of one set of curves from its parents. This unidirectional process has been extended to bi-directional parameterization by superimposing two sets of unidirectional curves generated from both boundary pairs. Case studies show that this algorithm gives reasonably smooth transformation of the boundaries. This algorithm is more robust than the linear Coons method and capable of resolving the 2D boundary-conformed parameterization problems.

• Proceedings of the IEEK Conference
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• 1998.10a
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• pp.723-726
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• 1998

Fault dropping is a very important part of test generation process. It is used to reduce test generation time. Test generation systems use fault simulation for the purpose of fault dropping by identifying detectable faults with generated test patterns. Two kinds of delay fault model is used in practice, path delay fault model and gate delay fault model. In this paper we propose an efficient method for gate delay test generation which shares second test vector.

• Investigative Magnetic Resonance Imaging
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• v.5 no.1
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• pp.24-32
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• 2001

Purpose : We investigated the reproducibility of language lateralization by 4 different word generation paradigms or the rest contents in each paradigm using functional magnetic resonance imaging in normal volunteers Materials and Methods Nine normal volunteers with left-handedness (mean age: 25 yrs) were examined on a 1.57 MR unit using a single-shot gradient echo epibold sequence. Four different word generation paradigms of noun, verb, adjective and adverb were used in each normal volunteer for investigating language system. In each paradigm, two different rest contents consisted of only seeing the " +" symbol or reading the meaningless letters. Each task consisted of 96 phases including 3 activations and 6 rests of 2 different contents. Two activation maps in one task were obtained under two different rest contents using the correlation method. We evaluated the detection rates of Broca and Wernicke areas and the differences of language lateralization among four different word generation paradigms, or between the rest contents. Results : The detection rates of Broca and Wernicke areas were over 67 % in 4 different language paradigms and there was no significant difference of them among language paradigms, or between two different rest contents. Language dominances, in all 4 different language paradigms, were shown to be consistent in 66 %, but were contrary with language paradigms in some subjects. The rest contents made no significant effect on dominant language dominance determination, but the success rates of the dominant language dominances determined from 4 language paradigms were higher in reading the meaningless letter (100%, n=9) than in only seeing "+" on screen at the rest task (78%, n=7).

• Journal of Families and Better Life
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• v.22 no.6 s.72
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• pp.155-164
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• 2004

The purpose of this study is to discover similarities and dissimilarities in life style and other factors for housing choices between two generations living in same household. It will provide knowledge that is helpful in understanding the two generations and develop marketing strategies for houses as a commodity that accommodates the life style of both generations. The data of this study were collected from October to November 2003, using a structured, self-report questionnaire that contains questions on 40 dimensions of life style and 33 items on housing choices. The original respondents consisted of 307 university students and their parents living in Seoul. The ages of the younger generation were limited from ぉ to 29. The final participants in this study included 224 sets of university students and their parents, that is, about 448 respondents. Frequency, percentage, factor analysis, paired t-test and means were used for data analysis. The results show that the life style may be divided into nine sub-types. There were generational differences in If-oriented lifestyle, Conservative lifestyle, As- service self-expression lifestyle, Pragmatic lifestyle, Convenience lifestyle, Self-development lifestyle, and Leisure-oriented lifestyle. Especially in the categories of Convenience lifestyle, If-oriented lifestyle and Positive Self-expression lifestyle, the younger generation ranked higher than their parents. The most important factors in housing choice may be divided into eight sub-categories. Among them are economic factors, housing amenities, housing design, distance from parents and children, social and environmental qualifies, and distance from work place and school. The two generations differed over the importance of the factors. The younger generation particularly valued the factors of distance from parents and children, housing amenities, housing design.

• Journal of the Korean Society of Clothing and Textiles
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• v.34 no.6
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• pp.902-912
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• 2010

This study compares and contrasts the consumer decision-making styles (CDMS) of South Korean and American Generation Y females. A total of 117 American female and 206 Korean female consumers completed self-report survey questionnaires to assess their consumer decision making styles. Exploratory principal components factor analysis using varimax rotation was used to categorize the items into an underlying set of American and Korean decision-making characteristics. Two-tailed independent t-tests were conducted to examine the differences between the two groups when items appeared to have common factors. Factor analysis identified five common factors between the two samples (i.e., enjoyment, shopping aversion, price consciousness, brand consciousness, and quality consciousness). The t-test results report significant differences in the items reported in each factor between American and Korean females. Some of the factors are more indicative of American female Generation Y consumers than Korean female Generation Y consumers. For example, the American female sample seemed to enjoy shopping and prefer brand names more than the female Korean sample. Koreans females seem to have a higher aversion to shopping than Americans; in addition, Koreans females seem to be more accepting of discount and outlet stores, will wait until the price is low before buying a product, and prefer sales when shopping. Based on the findings, the instrument identified varying CDMS between the two samples used. Previous studies using the Sproles and Kendall (1986) instrument experienced the same issue (Bakewell & Mitchell, 2004, 2006; Bauer et al., 2006; Durvasula et al., 1996; Fan & Xiao, 1998; Hanzaee & Aghasibeig, 2008; Mitchell & Walsh, 2004; Siu et al., 2001; Walsh et al., 2001). The results support the idea that no single instrument can be used to examine CDMS in different cultures. This suggests that each country has a CDMS with internal characteristics. Limitations and research for future studies are also discusse.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.11 no.1
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• pp.109-116
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• 1991

In recent years, hydrologists have been interested in the radial spectrum and its estimation in two dimensional storm field to construct simulation model of the rainfall. This paper deals with the problem of transformation from the spectrum or isotropic covariance function to two dimensional random field. The extended turning band method for the generation of random field is applied to the problem using the line generation method of one dimensional stochastic process by G.Matheron. Examples of this generation is chosen in the random components of the multidimensional rainfall model suggested by Bras and are given with a comparison between theoretical and sample statistics. In this numerical experiments it is observed that first and second order statistics can be conserved. Also the example of moving storm simulation through Bras model is presented with the appropriate parameters and sample size.

• Journal of Engineering Education Research
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• v.20 no.5
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• pp.23-33
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• 2017

It is examined that how flipped learning and mind-wandering affect an idea generation task. For the purpose, the participants in the idea generation task are divided into two groups to learn SIT(Systematic Inventive Thinking) and BCC(Business Creativity Codes) as idea generating tools in advance. One group learned the tools in a classroom, and the other group through an online education program. The creativity level of an idea is evaluated in the dimensions of originality, practicality, and realizability. The creativity levels of the ideas from the two groups are not statistically different in all the three creativity dimensions. To examine the effect of mind-wandering, another group generated ideas two hours a day in four days instead of eight hours in one day. The creativity levels of the ideas from the third group are higher in the dimensions of originality and practicality. This shows that the effectiveness of flipped learning is not so different from the face-to-face learning in a classroom, and mind-wandering has a positive effect in the learning.

• Journal of the Korean Applied Science and Technology
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• v.27 no.4
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• pp.415-420
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• 2010

This study is focused on the channel design of bipolar plate in the electrode of hydrogen gas generator. The characteristics of hydrogen gas generation was studied in view of efficiency of hydrogen gas generation rate and a tendency of gas flow through the riv design of electrode. Since the flow rate and flow pattern of generated gas in the two phase flow system are the most crucial in determining the efficiency of hydrogen gas generator, we adopted the commercial analytical program of COMSOL MultiphysicsTM to calculate the theoretical flow rate of hydrogen gas from the outlet of gas generator and flow pattern of two phase fluid in the electrode. In this study, liquid electrolyte flows into the bipolar plate and decomposed into gas phase, two phase flow simulation is applied to measure the efficiency of hydrogen gas generation.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.25 no.6
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• pp.1004-1014
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• 2001

The fully automatic algorithm from initial finite element mesh generation to remeshing in two dimensional geometry is introduced using bubble packing method (BPM) for finite element analysis. BPM determines the node placement by force-balancing configuration of bubbles and the triangular meshes are made by Delaunay triangulation with advancing front concept. In BPM, we suggest two node-search algorithms and the adaptive/recursive bubble controls to search the optimal nodal position. To use the automatically generated mesh information in FEA, the new enhanced bandwidth minimization scheme with high efficiency in CPU time is developed. In the remeshing stage, the mesh refinement is incorporated by the control of bubble size using two parameters. And Superconvergent Patch Recovery (SPR) technique is used for error estimation. To verify the capability of this algorithm, we consider two elasticity problems, one is the bending problem of short cantilever beam and the tension problem of infinite plate with hole. The numerical results indicate that the algorithm by BPM is able to refine the mesh based on a posteriori error and control the mesh size easily by two parameters.