• JSTS:Journal of Semiconductor Technology and Science
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• v.13 no.5
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• pp.516-521
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• 2013

This paper investigates the two dominant but intertwined current blocking mechanisms of Switching and Kirk Effect in pure ternary InAlAs/InGaAs/InAlAs Double Heterojunction Bipolar Transistors (DHBTs). Molecular Beam Epitaxy (MBE) grown, lattice-matched samples have been investigated giving substantial experimental results and theoretical reasoning to explain the interplay between these two effects as the current density is increased up to and beyond the theoretical Kirk Effect limit for devices of emitter areas varying from $20{\times}20{\mu}m^2$ to $1{\times}5{\mu}m^2$. Pure ternary InAlAs/InGaAs/InAlAs DHBTs are ideally suited for such investigations because, unless corrective measures are taken, these devices suffer from appreciable current blocking effect due to their large conduction band discontinuity of 0.5 eV and thus facilitating the observation of the two different physical phenomena. This enhanced understanding of the interplay between the Kirk and Switching effect makes the DHBT device design and optimization process more effective and efficient.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.22 no.3
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• pp.24-32
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• 2014

Due to the rapid growth of domestic and overseas airline markets, the demand for airline pilots has also been growing fast. Meeting such a market needs, central government, Ministry of Land and Transportation has set up civil airline pilot training center at Ulgin airport to train and provide the market with commercial airline pilots. Not only central government but universities in Korea also have tried to train pilots by operating flight training academies. Even though there are more than a dozen of flight training centers including colleges and private academies, there have been less efforts to measure and evaluate the effectiveness of the flight training school's curriculums compared to other scholar majors in a university. Therefore this paper tried to evaluate the educational effectiveness of the curriculums using the Kirk-Patrick measurement model, which has been regarded as one of the most popular and accurate measurement tool for an empirical research in social science. According to the empirical research, it was found out the inter-personal relationship between an instructor pilot and flight trainee was perceived as the most important factor to have an impact on learning abilities and student's behaviors.

• Science of Emotion and Sensibility
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• v.25 no.3
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• pp.107-116
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• 2022

Purpose: Researchers have shown that aesthetic judgments of artworks depend on contexts, such as the authenticity of an artwork (Newman & Bloom, 2011) and an artwork's location of display (Kirk et al., 2009; Silveira et al., 2015). The present study aims to examine whether contextual information related to the creator, such as whether an artwork was created by a human or artificial intelligence (AI), influences viewers' preference judgments of an artwork. Methods: Images of Impressionist landscape paintings were selected as human-made artworks. AI-made artwork stimuli were created using Google's Deep Dream Generator by mimicking the Impressionist style via deep learning algorithms. Participants performed a preference rating task on each of the 108 artwork stimuli accompanied by one of the two creator labels. After this task, an art experience questionnaire (AEQ) was given to participants to examine whether individual differences in art experience influence their preference judgments. Results: Setting AEQ scores as a covariate in a two-way ANCOVA analysis, the stimuli with the human-made context were preferred over the stimuli with the AI-made context. Regarding the types of stimuli, the viewers preferred AI-made stimuli to human-made stimuli. There was no interaction effect between the two factors. Conclusion: These results suggest that preferences for visual artworks are influenced by the contextual information of the creator when the individual differences in art experience are controlled.

• Korean Journal of Materials Research
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• v.12 no.6
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• pp.470-475
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• 2002

The effects of the conditions of the collector formation on electrical characteristics of the packaged SiGe hetero-junction bipolar transistors (HBT) were investigated. While the DC characteristics of SiGe HBTs such as IV characteristic, forward current gain, Early voltage, and breakdown voltage were hardly changed after packaging, the AC characteristics such as $f_{\tau}\; and\; f_{max}$ were degraded severely. With the rise of the collector concentration, the break-down voltage decreased but the $f_{\tau}$ increased. Additionally, $\beta$ and $f_{\tau}$ values were kept high in the range of elevated collector current due to the increase of the critical current density for the onset of the Kirk effect. The devices As implanted before the collector deposition showed lower breakdown voltage and higher $f_{\tau}$ than the others, which seems to be originated from the As up-diffusion resulting in the thinner collector.

• Journal of the Korean Society of Clothing and Textiles
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• v.29 no.8 s.145
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• pp.1168-1175
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• 2005

Clothing pressure has close relation with clothing comfort and depends on the pattern and properties of textile fabrics. Choosing a suitable clothing pressure is an essential factor for designing functional clothing such as the foundation for reshaping of a body contour or medical items for bum patient, and etc. However, it is hard to measure pressure values at the curved surface of a human body correctly. Recently, an air pack type pressure sensor, which has relatively excellent performance has been used to measure clothing pressure, however, it is still inconvenient to apply because it is a contact- type sensor. Therefore, in this paper, we suggest an indirect method that can measure clothing pressure without touching the subject by improving the equation of Kirk and Ibrahim (1966). However, confusions have been occurred when someone use the equation since the definition of parameters are somewhat vague. Furthermore, the estimated clothing pressure obtained by the previous method are quite different from the real values because this method does not consider the 3D effect of a human body and property changes of a transformed fabric. In this paper, the direction of principal stress and the radius of curvature in the principal direction were searched in the 3D image of the deformed girdle to get more accurate clothing pressure. The estimated clothing pressure was verified by comparing the result of the air pack type pressure sensor. It was found that the accuracy of the pressure estimation was improved by considering the 3D curvature of human body and the directional characteristics of textile fabrics.