• Geophysics and Geophysical Exploration
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• v.9 no.2
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• pp.148-154
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• 2006

The effect of small-scale near surface inhomogeneity on Rayleigh wave propagation and dispersion has been investigated in this study using two-dimensional FEM elastic modeling. Various inhomogeneity models with a variety of geometrical shape and embedment depth which exist in homogeneous half-space and two-layered media are considered. Results show that any near surface inhomogeneity greater than one wavelength in terms of minimum wavelength of Rayleigh wave shows dispersion characteristics. Such dispersion effect become stronger as the dimensions of the inhomogeneity increase. The effect of horizontal dimension is more dominant factor governing the dispersion characteristics than vertical dimension. However, the dispersion effect can not be identifiable in seismogram if the horizontal dimension is not wide enough. Nonetheless, even in this case, the existence of inhomogeneity can be inferred by the reflection or transmission event of Rayleigh wave. The results can be expected to provide insights on the behavior of Rayleigh wave which may be helpful for designating field work or new processing scheme to detect near surface inhomogeneity by surface wave method.

• Journal of Digital Convergence
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• v.13 no.3
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• pp.155-165
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• 2015

Bankruptcy prediction has been one of the important research topics in finance since 1960s. In Korea, it has gotten attention from researchers since IMF crisis in 1998. This study aims at proposing a novel model for better bankruptcy prediction by converging three techniques - support vector machine(SVM), fuzzy theory, and genetic algorithm(GA). Our convergence model is basically based on SVM, a classification algorithm enables to predict accurately and to avoid overfitting. It also incorporates fuzzy theory to extend the dimensions of the input variables, and GA to optimize the controlling parameters and feature subset selection. To validate the usefulness of the proposed model, we applied it to H Bank's non-external auditing companies' data. We also experimented six comparative models to validate the superiority of the proposed model. As a result, our model was found to show the best prediction accuracy among the models. Our study is expected to contribute to the relevant literature and practitioners on bankruptcy prediction.

• Journal of Welding and Joining
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• v.26 no.4
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• pp.79-84
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• 2008

Use of sheet metal structure is increased in various fields such as automobile, aerospace and communication equipment industry. When this structure is welded, welding distortion is generated due to the non-uniformity of temperature distribution. Recently welding distortion becomes a matter of great importance in the structure manufacture industry because it deteriorates the product's quality by bringing about shape error. Accordingly many studies for solving the problems by controlling the welding distortion are being performed. However, it is difficult to remove all kinds of distortion by welding process, though various kinds of methods for reducing distortion are applied to production. Consequently, straightening process is operated if the high precision quality is requested after welding. The local heating method induces compression plastic deformation by thermal expansion in the heating stage and then leaves constriction of length direction in the cooling stage. Accordingly, in the case of sheet metal structure, straightening effect is expected by heating for the part of distortion. This study includes numerical analysis of straightening effect by the local heating method in distortion comes from production of welded sheet metal structure. Particularly straightening effect followed by dimensions of heating area is analyzed according to the numerical analysis. The numerical analysis is performed by constructing 3-dimensional finite element model for 0.4mm stainless steel-sheet metal. Results of this study confirm that straightening effect changes as heating area increases and the optimum value of heating area that proves the maximum straightening effect exists.

• Journal of the Korea institute for structural maintenance and inspection
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• v.11 no.2
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• pp.145-154
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• 2007

As buildings are built higher and their service life made longer, face brick walls are also required to be constructed in an easy and systematic manner, and to ensure their satisfying structural performance, inspectingly, against lateral load. Therefore this study aims to investigate the structural performance of face brick walls constructed by a new method using screwed stainless steel connectors and provide fundamental experiment data for field application of this method. The results of this study indicated that the face brick wall tied with screw connectors had better shear capacity against rocking motion than that of the wall constructed with ordinary tie bars when their tie spacing was the same. Based on the good performance of the wall tied with the screw connector, it is also expected that the spiral anchors developed in this study can possibly applied to high-rise by adjusting the spacing of the anchors considering the difference of dimensions.

• Journal of Convergence for Information Technology
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• v.10 no.2
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• pp.9-14
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• 2020

This study studied on innovation and R&D performance measurement, and especially the dimensions of measuring performance. The Empirical study is based on the opinions of 169 experts from a R&D group with a career for SMBA's support. The results reveal that what the most optimal and appropriate measures of project-level success are will depend on the type of innovation involved and the development project type and the relatively low significance of financial measures for innovation projects in general. Additionally, measurability is not major significance factor for selecting measures, whereas the level of innovativeness were to be selected as important factor. The roles of the evaluators are affected. It is expected to help make government policy for R8D performance evaluation.

• Proceedings of the Korea Association of Information Systems Conference
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• 2004.11a
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• pp.201-208
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• 2004

Many organizations experience that the Performance they gained from IT portfolio is lower than they expected values. As with any investment, executives are concerned with maximizing the performance from their investment in IT. This study focused on the relationship or fit between orientations of IT strategy and directions of IT portfolio to maximize IT performance. A field survey of chief information officers of Korea manufacturing sector was conducted in 2003. Complete data of 147 firms was analyzed to determine relationship among the three research constructs that are orientations of IT strategy, directions IT portfolio, and IT performance. In this study, the orientations of IT strategy have two dimensions that are operation orientation and market orientation. The directions of IT portfolio have two dimension that are internal system focused and external system focused. And the IT performance has divided into operational performance and competitive performance. As a result of this study, the companies that are putting a focus with operation orientation were concentrated on internal information systems than external information systems. On the other hand, the other companies that are focused on market orientation were concentrated on external information systems than internal information systems. Consequently, the companies that are focused on operation orientation were operational performance higher than competitive performance and the other companies that are focused on market orientation were competitive performance higher than operational performance. More importantly, the research results provide empirical evidence that supports the hypothesis related to closer fit between IT strategy and IT portfolio does lead to increase operational and competitive performance of IT. And the results emphasize manager's efforts of fit between orientations of IT strategy and directions of IT portfolio to be realized IT performance.

• Journal of Digital Contents Society
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• v.18 no.3
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• pp.475-483
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• 2017

This study attempted to investigate how the effectiveness of value-oriented promotion for media contents depends on self-construal and incorporated Schwartz' value system theory(1992) and Gutman's means-end chain theory(1982) into the development of hypotheses. It was expected that media content promotion emphasizing "openness to change" value would be more appealing to those with independent self-construal, whereas media content promotion emphasizing "conservation" value would be more appealing to those with interdependent self-construal. These hypotheses were generally supported in a series of experiments. Also, the dynamic relationship among the four primary value dimensions proposed by Schwartz (i.e., openness to change, conservation, self-enhancement, self-transcendence) was clearly validated in this study.

• Journal of Digital Convergence
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• v.11 no.7
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• pp.9-18
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• 2013

In this paper, we investigated the satisfaction of incorporation founder through the Startbiz System. We also expected that the research results contribute to draw the development plan of Startbiz System afterward. The satisfaction in the Startbiz System was investigated in four dimensions such as the company establishing service, the website quality, the business promotion environment of the associated organizations, and providing information. The satisfaction appeared for the order of the company establishing service, providing information, the website quality, and the business promotion environment of the associated organizations. It's necessary to improve of the business promotion environment of the associated organizations for activating an incorporation utilizing the Startbiz System.

• Journal of the Ergonomics Society of Korea
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• v.29 no.6
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• pp.831-841
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• 2010

Usability evaluation of physical products involves characterizing complex physical interactions between humans and products. Human models known as manikins have been widely utilized as usability evaluation tools for automobile interior package design. When combined with computer-aided design software programs, such manikins can be used to simulate driving postures and evaluate driver-interior fits early in the design process, and therefore, may greatly facilitate achieving high-quality design in a cost-efficient manner. The purpose of this study was to define a set of manikins for designing automobile interior packages for the South Korean male population. These manikins were conceptualized as "boundary" manikins, which represent individuals lacking in certain physical capacities or having usability-related issues (e.g., an individual with the 5th percentile forward reach capability, an individual with the 95th percentile shoulder width). Such boundary manikins can serve as an efficient tool for determining if an automobile interior design accommodates the majority of the population. The boundary manikins were selected from the large sample of Korean males whose anthropometric dimensions were described in the recent Size Korea anthropometric database. For each male in the database, his comfortable driving posture was represented using a kinematic body linkage model and various physical capacity measured and usability-related characteristics relevant to driver accommodation were evaluated. For each such measure, a boundary manikin was selected among the Korean males. The manikins defined in this study are expected to serve as tools for ergonomic design of automobile interior packages. The manikin selection method developed in this study was implemented as a generic software program useful for various product design applications.

• Korean Journal of Social Welfare
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• v.63 no.1
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• pp.85-111
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• 2011

This study has the purpose to measure the multidimensional poverty in Korea by the counting approach which was theorized by Alkire and Foster to overcome problems of unidimensional approach, union method and intersection method for the identification of the multidimensional poor. By the counting approach applying to Welfare Panel in Korea during 2006-2008, the head-count ratio of the multidimensional poverty was measured. When 3 dimensions are applied as a dimension poverty line, the multidimensional poverty rate was 20% in 2008. It was due to broad deprivations in assets, social securities, income and health. Vulnerable classes such as single parent families, low-education level group, the aged, economically non-active population were among the severe poverty rates, which were reaching around 50%. The analysis reveals the possible alternative to change the present public assistance program to the robust approach of multidimensional poverty measurement, the counting approach. Social policies to reduce poverty in Korea would gain expected positive outcome with the various approaches based on the concepts of multidimensional poverty.