• Korean Journal of Child Studies
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• v.29 no.4
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• pp.43-63
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• 2008

This study developed an experience-based economic education program and examined its effects on young children's economic concepts and purchasing behavior. Subjects were 60 5-year-old kindergarteners assigned to an experimental or a control group. Instruments for pre- and post-tests were the Economic Concept Task (Laney, 1995) and the Purchasing Behavior Task (Jang, 2004). Experimental group children participated in the economic education program for 5 weeks; control group children listened to economic stories. Differences between pre- and post-test in the experimental group showed that the economic education program was effective in development of concepts of scarcity, opportunity cost, resource/production, goods/services, and complements/substitutes. Children's purchasing behavior changed partially after application of the program.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.37 no.11
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• pp.753-761
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• 1988

Partial Matrix Refactorization (PR) has been available for refactorization repeatedly. But this paper aims to present Modified PR(MPR), which is faster in (re) factorization speed and simpler in program than PR, but storage is almost as big as that of PR. MPR substitutes refactorization process of PR1 for Modifide Trifactortzation (MT) and, instead of PR 2, adds to PR1 the algoritm that calculates modified element values of modified row / cols. MT, which is subalgorithm for MPR, simplifies the algorithm by applying information vectors to currently used Trifactorization, and trifactorizes and refactorizes in high speed. The test results of Fast Decoupled Load Flow (FDLF) and Contingency Analysis useing Indexing Scheme and Optimal Ordering also prove that MPR is faster than PR.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.26 no.2
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• pp.87-91
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• 2013

Carbon-nanotube field-effect transistors (CNFETs) have drawn wide attention as one of the potential substitutes for metal-oxide-semiconductor field-effect transistors (MOSFETs) in the sub-10-nm era. Output characteristics of coaxially gated CNFETs were simulated using FETToy simulator to reveal the dependence of drain current on the nanotube diameter and gate oxide thickness. Nanotube diameter and gate oxide thickness employed in the simulation were 1.5, 3, and 6 nm. Simulation results show that drain current becomes large as the diameter of nanotube increases or insulator thickness decreases, and nanotube diameter affects the drain current more than the insulator thickness. An equation relating drain saturation current with nanotube diameter and insulator thickness is also proposed.

• The Journal of Information Technology
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• v.9 no.3
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• pp.49-57
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• 2006

Electronic paper technology is technology make e- paper, and studying an electronic device is thin like a paper book, an electronic device having made so as to be able to feel as it is feeling of paper like paper newspaper/paper magazines etc. and papers, and crumple freely, or to be able to fold. While electronic paper substitutes for role of paper, a digital function has at the same time a lot of the acids which shall exceed to implement. Necessary, and the continuous researcher who can solve a problem of a fast answer speed for animation implementation, collar implementation and low drive voltage is important a security of a patent right preparing for new market formation, too very in order to form the market where electronic paper can substitute for papers and the existing display as indication elements of a dream, and shall be made to achieve a continuous technical researcher.

• Journal of the Korean Institute of Intelligent Systems
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• v.8 no.2
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• pp.1-8
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• 1998

In this paper, a method which cna detect tracking caused by the insulation deterioration of conduct wiring, is proposed. To investigate it, we analyzed the harmonics of each load current waveform and those of tracking current waveform with FFT. The computer which take experiment data is learned by neural network algorithm, which has recently been used for the load recognition. The proposed metod in our study can be applied to the development of several measuring equipments such as hotline insulation tester, cna earch tester for the detection of tracking under hot-line state, Furthermore, it can substitutes molded case circuit breaker, fuse, and so on.

• Proceedings of the IEEK Conference
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• 2003.07b
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• pp.1213-1216
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• 2003

This paper proposes an 3D graphics rendering processor for portable device. One the most important factor is chip size for portable device, but the conventional 3D graphics rendering processor is not a suitable because the processor needs a lot of multiplication and division units. So the proposed architecture substitutes single precision floating point by 32 bit fixed point, and uses recursive units for the same operation such as color values(z, r, g, b, a) and texture values (s, t, u, v). In this approach, we reduce numbers of multiplications and divisions by 66.1% and 75% respectively at the sacrifice of performance degradation by 2.12%.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.38 no.5
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• pp.264-270
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• 2012

Many oral and maxillofacial bone defects are not self-healing. Guided bone regeneration (GBR), which uses a barrier membrane to prevent the soft tissues from invading the defect to enable slower-growing bone cells to penetrate the area, was developed as a therapy in the 1980s. Although there has been some success with GBR in some clinical situations, better treatments are needed. This review discusses the concept of GBR focusing on bioactive membranes that incorporate osteoconductive materials, growth factors and cells for improved oral and maxillofacial bone regeneration.

• Journal of National Security and Military Science
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• s.7
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• pp.91-128
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• 2009

Society is developing fast. Nobody could expect that computer could be used in purpose of trajectory calculation when the ANIAC was developed in the past. However, nowadays technology development brought computerization which substitutes to mankind's working. And personal computer including internet make our society to be IT age. Such age is in revolutionizing now that could be able to bring a new paradigm. We should prepare to such change which scholars predict the end of revolution could be reached at ubiquitous age. This study is purposing firstly for predicting which changes are arisen in the defence sector when social system will become ubiquitous age. That is how change of ubiquitous paradigm could influence to the defence sector and which appearance could be arisen in ubiquitous defence environment. The second purpose of this study is to predict the characteristics of Planing, Programing, Budgeting, Executing, Evaluating, System (PPBEES) of the defence sector.

• Journal of the Society of Disaster Information
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• v.5 no.2
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• pp.124-137
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• 2009

The research on the effect of the prestressing force on the frequency of PSC(Prestressed Concrete beam) has been conducted theoretically and experimentally, and a few theory has been presented. However, the presented theories show no agreement in predicting the effect of the prestressing force. In this paper, the theories on the effect of the prestressing force on the frequency of PSC beam are presented and evaluated using the experimental result. To obtain the experimental result, two PSC beam specimens were manufactured, and the modal test and analysis were performed. The modal analysis results revealed that the prestressing force increased the natural frequency of the PSC beam. Comparing predicted results using existing theories show that Kim's model, which substitutes the prestressing tendon with the equivalent beam, gives the best prediction result.

• Journal of the Korea Furniture Society
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• v.10 no.2
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• pp.17-27
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• 1999

As a countermeasure to reach self-sufficiency for wood supply and demand, we have to develop wood substitutes. Rice hull is the cheapest fiber material we can get in Korea, What is better the yield of rice hull amounts to 1 million tons per year. Before carrying out this study, new ecomaterial rice hull board for housing materials was developed successfully. In order to evaluate whether the rice hull board with or without bioceramic treatment is suitable for housing materials, we studied the environmental effect of the above materials in comparison with the polycarbonate, stainless, or concrete on the adaptation (body weight, water/feed consumption, general signs, urinalysis, autopsy, etc) and the reproduction(litter size, newborn adaptation, etc)of mice. In conclusion, the concrete cage was the worst in the adaptation and so was the stainless steel cage in the reproduction. The rice hull board cage with or without bioceramic treatment was superior or equivalent to other material cages from the standpoints of the adaptation and reproduction.