• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.32 no.10
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• pp.12-19
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• 2004

An aerodynamic design optimization system for three-dimensional wing was developed as a part of the future MDO framework. The present design optimization system includes four modules such as geometry design, grid generation, flow solver and optimizer. All modules were based on commercial softwares and programmed to have automated execution capability in batch mode utilizing built-in script and journaling. The integration of all modules into the system was accomplished through programming using Visual Basic language. The distributed computational environment based on network communication was established to save computational time especially for time-consuming aerodynamic analyses. The distributed aerodynamic computations were performed in conjunction with the global optimization algorithm of response surface method, instead of using usual parallel computation based on domain decomposition. The application of the design system in the drag minimization problem demonstrated considerably enhanced efficiency of the design process while the final design showed reasonable results of reduced drag.

• Journal of Korean society of Dental Hygiene
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• v.12 no.5
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• pp.849-859
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• 2012

Objectives : The purpose of this study was to examine the educational effects of team learning by having learners keep a journal to record, check and reflect on their own learning. It's basically meant to investigate the effects of team learning on learning motivation and academic achievements to provide some information on teaching-learning strategy setting tailored to learner characteristics. Methods : The subjects in this study were 49 college sophomores. After they were divided into an experimental group and a control group, the experimental group of 24 students engaged in team learning from March to June, 2012, and that group was asked to keep a reflective journal every week to determine whether writing a reflective journal in every session served to boost their learning motivation and academic achievement or not. Results : 1. After the experimental group kept a reflective journal, that group underwent a significant change in learning motivation from a mean of 3.34 in the pretest to a mean of 4.01 in the posttest(p<0.05). The experimental group showed a more positive improvement than the control group. 2. After the experimental group kept a reflective journal, they underwent a significant change in academic achievement from 22.7 in the pretest to 23.5 in the posttest(p<0.05). The control group showed no significant improvement in academic achievement. Conclusions : The findings of the study illustrated that keeping a reflective journal had a positive impact on the learning motivation of the learners, and the findings of the study are expected to lay the foundation for future research in new teaching methods for the department of dental hygiene.

• Journal of KIISE:Computing Practices and Letters
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• v.16 no.2
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• pp.247-251
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• 2010

Using SCM in storage systems introduce new potentials for improving I/O performance and reliability. In this paper, we study the use of SCM as a buffer cache that guarantees transactional unit writes. Our proposed method can improve storage system reliability and performance at the same time and can recover the storage system immediately upon a system crash. The Proposed method is based on the LINUX JBD(Journaling Block Device), thus reliability is equivalent to JBD. In our experiments, the file system that adopts our method shows better I/O performance even while guaranteeing high reliability and shows fast file system recovery time (about 0.2 seconds).

• Journal of Korean Society of Industrial and Systems Engineering
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• v.41 no.2
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• pp.153-158
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• 2018

At the Bank of Korea, capital stock statistics were created by the PIM (perpetual inventory method) with fixed capital formation data. Asset classifications also included 2 categories in residential buildings, 4 non-residential buildings, 14 constructions, 9 transportation equipment, 28 machinery, and 2 intangible fixed assets. It is the Korean government accounting system which is developed much with the field of the national accounts including the valuation, but until 2008 it was consistent with single-entry bookkeeping. Many countries, including Korea, were single-entry bookkeeping, not double-entry bookkeeping which can be aggregated by government accounting standard account. There was no distinction in journaling between revenue and capital expenditure when it was consistent with single-entry bookkeeping. For example, we would like to appropriately divide the past budget accounts and the settlement accounts data that have been spent on dredging into capital expenditure and revenue expenditure. It, then, tries to add the capital expenditure calculated to FCF (fixed capital formation), because revenue expenditure is cost for maintenance etc. This could be a new direction, especially, in the estimation of capital stock by the perpetual inventory method for infrastructure (SOC, social overhead capital). It should also be noted that there are differences not only between capital and income expenditure but also by other factors. How long will this difference be covered by the difference between the 'new series' and 'old series' methodologies? In addition, there is no large difference between two series by the major asset classification level. If this is treated as a round-off error, this is a problem.