• Journal of Digital Convergence
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• v.15 no.6
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• pp.19-27
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• 2017

The purpose of this study was to analyze the differences of creativity according to major of college students focusing on pre-service early childhood teachers, pre-designers and pre-engineers. The subjects were 132 four grade of university students attending K and T university in Busan, Korea. Data were analyzed with one-way MANOVA to find out the differences of creativity according to their major. Results of this study as follows: first, overall creativity was significantly higher in preliminary designers than pre-service early childhood teachers and pre-engineers. Second, the fluency of pre-service early childhood teachers and pre-designers was significantly higher than that of pre-service engineers. The abstraction was significantly higher in pre-service early childhood teachers than pre-engineers. The elaboration of pre-designers was significantly higher than that of pre-service teachers and pre-engineers. Openness was significantly higher in pre-designers than pre-engineers, and pre-engineers were significantly higher than pre-service early childhood teachers. Therefore, this study suggests that the major in creativity curriculum and program development for college students should be considered, and the results of this study will be used as basic data of the creativity education program.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1999.05a
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• pp.370-373
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• 1999

Si direct bonding (SDB) technology is very attractive for both Si-on-insulator(SOI) electric devices and MEMS applications because of its stress free structure and stability. This paper presents on- pre treatment conditions in Si wafer direct bonding, The paper resents on pre-bonding according to HF pre-treatment conditions in Si wafer direct bonding. The characteristics of bonded sample were measured under different bonding conditions of HF concentration, applied pressure and annealing temperature(200~ 100$0^{\circ}C$) after pre-bonding. The bonding strength was evaluated by tensile strength method. The bonded interface and the void were analyzed by using SEM and IR camera, respectively, Components existed in the interlayer were analyzed by using FT-IR. The bond strength depends on the HF pre-treatment condition before pre-bonding(Min 2.4kgf/$\textrm{cm}^2$~ Max : 14.kgf/$\textrm{cm}^2$)

• Journal of The Korean Society of Agricultural Engineers
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• v.58 no.6
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• pp.71-77
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• 2016

This study was to evaluate the feasibility of pre-consolidation pressure distribution characteristic of western and southern coastal region, using correlation of unconfined compressive strength and preceding research equation. Pre-consolidation of western and southern region showed similar trends undrained shear strength and pre-consolidation pressure in proportion to unconfined compressive strength. Predicted results of U.S. NAVY. (1982) equation revealed a small error western 9.7 % and southern 0.4 %. Prediction correlation results of pre-consolidation using unconfined compressive strength revealed an error western 16.8 % and southern 0.7 %. It was reported that less than 20 percent of pre-consolidation pressure prediction result of Casagrande forecasting error. Estimates of pre-consolidation pressure are possible, before the standard consolidation test, because it was reported that less than 20 % of the forecasting errors of Casagrande.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 2003.10a
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• pp.539-542
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• 2003

In South Korea, flooding is controlled with large or small reservoirs scattered spatially over the territory. Because recent unexpected hard-rain events requires more flood control capacities, the pre-release system is considered with the most economical alternative. In this case time and volume of discharge should be determined by the simulation. But, existing pre-release simulation system has the problem of specificity. Therefore, GASS is considered to estimate the pre-release time and volume with different configurations of pre-release system. This paper shows that pre-release simulation system could be constructed with arranging GASAtmosphere, GASWatershed, Reservoir, Gate components using GASS. It is also shows that GASS could be used as a foundation for constructing pre-release simulation system that is easy to use and is flexible to reflect the changing configurations of reservoir systems.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 1996.03a
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• pp.41-46
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• 1996

In this study, unsintered and pre-sintered low purity alumina ceramics were machined with various tools to clarify the machinability, optimum tool materials and optimum cutting conditions. The main conclusions obtained were as follows. (1)In the case of dry cutting, the sintered diamond and natural diamond tools exhibit better performance in machining of the ceramic pre-sintered at lower temperature, and the tool lives of both tools in machining the ceramics pre-sintered at high temperature becomes extremely short. (2)The performance of CBN tool becomes better in dry machining of the ceramics pre-sintered at higher temperature. (3)When the pre-sintered ceramics were wet machined with sintered diamond, the tool life becomes considerably long, and higher cutting speed can be used than in the case of the CBN and ceramic tools, the tool lives becomes shorter at wet cutting than at dry cutting, especially exhibiting extremely short tool life in wet cutting with ceramic tool.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.64 no.10
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• pp.1501-1507
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• 2015

The contact wire pre-sag in railway overhead catenary has been considered as a innovative idea which improves the current collection quality and is expected to evenly distribute wear along a span. However, long term studies on the effects of pre-sag, especially on the quantitative wear pattern of the contact wire, have not yet been reported. Therefore, in this study, the pre-sag and wear pattern of the contact wire along a span from long term operation of railway in Korea was surveyed. The examination was conducted on 3 lines, the Gyeongbu high-speed line with pre-sag of span/2000, the Gyeongbu existing line without pre-sag, and Gyeongchun line with pre-sag installation on 1/1000 of its span. The wear measurements of 58 sample spans were examined. The wear pattern analysis show no interrelationships between pre-sag and evenly distributed wear, but more wear occurred at the center of a span compared to the ends of the span, especially more noticeable as span length increases.

• The Transactions of the Korean Institute of Electrical Engineers D
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• v.50 no.12
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• pp.590-596
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• 2001

The pre-emphasis is an essential process for speech signal processing. Widely used two methods are the typical method using a fixed value near unity and te optimal method using the autocorrelation ratio of the signal. This study proposes a new pre-emphasis method using the short-term energy difference of speech signal, which can effectively compensate the glottal source characteristics and lip radiation characteristics. Using the proposed pre-emphasis, speech analysis, such as spectrum estimation, formant detection, is performed and the results are compared with those of the conventional two pre-emphasis methods. The speech analysis with 5 single vowels showed that the proposed method enhanced the spectral shapes and gave nearly constant formant frequencies and could escape the overlapping of adjacent two formants. comparison with FFT spectra had verified the above results and showed the accuracy of the proposed method. The computational complexity of the proposed method reduced to about 50% of the optimal method.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2008.06a
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• pp.375-376
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• 2008

The flashover of insulators in vacuum is the main factor to limit the performance of insulation in vacuum insulation system. It is believed that the pre-flashover phenomena would play a very important role in the procedure of the flashover in the interface between the insulators and vacuum. This paper is mainly concerned on the pre-flashover phenomena of Alumina insulators in vacuum. There are 24 different types of alumina insulators were tested with a 0.7/4 ${\mu}s$ pulsed voltage under a $1\times10^{-4}$Pa vacuum. The observed pre-flashover phenomena were classified and the pre-flashover characteristics were concluded. It is useful to study further on the flashover mechanism in vacuum.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.23 no.1
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• pp.18-23
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• 2010

We demonstrated that the solution processed organic light-emitting diodes (OLEDs) have the high efficiency with pre-treated indium-tin-oxide (ITO). ITO surface was pre-treated with four methods and compared each other. The pre-treatment of ITO surface improves the chemical and physical characteristics of ITO such as the surface roughness, adhesion property, and the hole injection ability. These properties were analyzed by the contact angle, atomic force microscope (AFM) image, and the current flow character in device. As a results, the device with ITO pre-treated by $O_2$ plasma shows the current efficiency of 5.93 cd/A, which is 1.5 times the device without pre-treatment.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.56 no.2
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• pp.260-267
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• 2007

Systematic studies on the dispatch scheduling algorithm can enhance the efficiency of electricity market operation. In addition, as the dispatching policies in competitive electricity markets directly affect the market participants' profits, the dispatch scheduling procedure should be reasonable, systematic, and transparent. In this paper, we propose an unconstrained/constrained pre-dispatch scheduling algorithm and develop corresponding programs applicable to wholesale electricity markets.