• Proceedings of the Korean Society of Precision Engineering Conference
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• 2012.10a
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• pp.231-232
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• 2012

• Asia pacific journal of information systems
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• v.5 no.1
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• pp.236-257
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• 1995

Not much attention has been paid to the characteristics of successful MIS in small business in Korea. This study compares the characteristics of successful MIS with those of less successful MIS of manufacturing industry in Korea in terms of micro level, macro level, and personal level. The micro level consists of those variables relating to the system development and maintenance while the macro level consists of the environmental variables relating to the information systems. The personal level measures a personal EDP experience. A mail survey was sent to small manufacturing companies to collect the data for the hypothesis tests. And 81 usable questionnaires were returned for data analysis. This study performs the validity of the categorization of variables in terms of three levels. The results shows that this categorization is appropriate but the personal level. As the personal experiences of EDP in Korea used to come up with those of the organization, the variables in the personal level have high correlations with those in the macro level in empirical testing. As the personal level, however, is different dimension from the macro level in theoretical aspect, the level is maintained separately throughout the study. The data were analyzed with MANOVA and two group discriminant analysis. The analyses reveal that the characteristics of successful MIS are different from those of less successful MIS in terms of three levels. And the micro level is more important than the macro level to develop successful MIS. That is because the organizations have relatively few experience in dealing with information systems, they have not developed unique information systems which are adjusted to their organizational characteristics. Those findings seems to be important determinants of success for the MIS in a firm.

• Journal of the Korean Geotechnical Society
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• v.38 no.8
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• pp.29-37
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• 2022

A three-dimensional analysis is required to interpret the drainage behavior of an improved ground with vertical drains, and the macroelement method enables efficient interpretation considering the three-dimensional drainage effect of vertical drains under two-dimensional plane strain condition. In this study, a novel finite element analysis program was developed by applying the macroelement method to the vacuum consolidation method used in ground improvement practice. The conventional macroelement method was used to calculate the amount of drainage from the vertical drain by setting the excess porewater pressure in the drainage material to zero; however, the program developed in this study was improved to consider negative excess porewater pressure as an actual vacuum consolidation condition. To verify the performance of the program, because of a comparison with the measurement values at the site where the vacuum consolidation method was applied, results predicted by the program and field measurement data showed similar settlement behavior.

• Proceedings of the Technology Innovation Conference
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• 2004.02a
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• pp.83-107
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• 2004

This study investigates how and through which channels R&D activities influences the national economy, using a macro-econometric model. The macro-econometric model in this study includes 24 behavioral equations and 25 identities and was estimated using the annual data. From a simulation analysis, it is shown that the R&D investment has a permanent effect on real variables; lowering prices, wages and interest rates, and increasing potential and real GDP in the long run. It is noted that the national account was recalculated to avoid double-counting in estimation of R&D stocks.

• Journal of IKEEE
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• v.16 no.2
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• pp.81-85
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• 2012

In this paper, we analyze the effect of mobility management method to the data rate of moving users when pico-cell which uses the same frequency bandwidth as that of macro-cell is overlaid over macro-cell. From this analysis, we show that the data rate which is available to the moving user depends on the method of mobility management and relative location of the overlaid pico-cell over macro-cell in the network.

• Earthquakes and Structures
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• v.25 no.3
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• pp.177-186
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• 2023

Reinforced concrete frames with a masonry infill panel is a structural typology frequently used worldwide. In seismic cases, the interaction between the masonry infill and the RC frames constitutes one of the most complex subjects in earthquake engineering. In this work, an enhancement of an existing numerical model is proposed to improve the estimation of lateral strength and stiffness of masonry-infilled frame structures and predict their probable failure modes. The proposed improvement is based on attributing corrective coefficients to the shear strength of each diagonal shear spring of the macro element, which simulates the masonry infill. The improved numerical model is validated by comparing the results with those of the original numerical model and with experimental results available in the literature. The enhanced macro element model can be used as a powerful, accessible tool for assessing the capacity and stiffness of masonry-infilled frame structures and predicting their probable failure modes.

• Journal of Information Technology Services
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• v.13 no.4
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• pp.275-287
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• 2014

Recently, the volume of unstructured text data generated by various social media has been increasing rapidly; consequently, the use of text mining to support decision-making has also been growing. In particular, academia and industry are paying significant attention to topic analysis in order to discover the main issues from a large volume of text documents. Topic analysis can be regarded as static analysis because it analyzes a snapshot of the distribution of various issues. In contrast, some recent studies have attempted to perform dynamic issue tracking, which analyzes and traces issue trends during a predefined period. However, most traditional issue tracking methods have a common limitation : when a new period is included, topic analysis must be repeated for all the documents of the entire period, rather than being conducted only on the new documents of the added period. Additionally, traditional issue tracking methods do not concentrate on the transition of individuals' interests from certain issues to others, although the methods can illustrate macro-level issue trends. In this paper, we propose an individual interests tracking methodology to overcome the two limitations of traditional issue tracking methods. Our main goal is not to track macro-level issue trends but to analyze trends of individual interests flow. Further, our methodology has extensible characteristics because it analyzes only newly added documents when the period of analysis is extended. In this paper, we also analyze the results of applying our methodology to news articles and their access logs.

• Journal of Power Electronics
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• v.18 no.5
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• pp.1489-1500
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• 2018

Partial shading analysis of large-scale photovoltaic (PV) arrays has recently become a theoretically and numerically challenging issue, and it is necessary for PV system designers. The main contributions of this study are the following: 1) A PSIM-based macro-model was employed because it is remarkably fast, has high precision, and has no convergence issues. 2) Three types of equivalent macro-models were developed for the transformation of a small PV sub-array with uniform irradiance to a new macro-model. 3) On the basis of the proposed new macro-model, a tearing method was established, which can divide a large-scale PV array into several small sub-arrays to significantly improve the efficiency improvement of a simulation. 4) Three platforms, namely, PSIM, PSpice, and MATLAB, were applied to evaluate the proposed tearing method. The proposed models and methods were validated, and the value of this research was highlighted using an actual large-scale PV array with 2420 PV modules. Numerical simulation demonstrated that the tearing method can remarkably improve the simulation efficiency by approximately thousands of times, and the method obtained a precision of nearly 6.5%. It can provide a useful tool to design the optimal configuration of a PV array with a given shading pattern as much as possible.

• Computers and Concrete
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• v.1 no.2
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• pp.211-226
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• 2004

A relatively simple multiple-vertical-line-element macro model has been incorporated into a standard computer code DRAIN-2D. It was used in blind predictions of seismic response of cantilever RC walls subjected to a series of consequent earthquakes on a shaking table. The model was able to predict predominantly flexural response with relative success. It was able to predict the stiffness and the strength of the pre-cracked specimen and time-history response of the highly nonlinear wall as well as to simulate the shift of the neutral axis and corresponding varying axial force in the cantilever wall. However, failing to identify the rupture of some brittle reinforcement in the third test, the model was not able to predict post-critical, near collapse behaviour during the subsequent response to two stronger earthquakes. The analysed macro model seems to be appropriate for global analyses of complex building structures with RC structural walls subjected to moderate/strong earthquakes. However, it cannot, by definition, be used in refined research analyses monitoring local behaviour in the post critical region.

• Proceedings of the IEEK Conference
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• 2005.11a
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• pp.1235-1240
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• 2005

This paper supposes the perfect power control at micro-cell and macro-cell. Under this supposition, we calculate SIR and decide the call admission by SIR. When we calculate SIR, we use the ratio of the power received the base station of micro-cell and the power received the base station of macro-cell. We analysis the performance of the system by the computer simulation while changing the ratio of power.