• Journal of electromagnetic engineering and science
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• v.9 no.2
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• pp.71-77
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• 2009

OFDM(Orthogonal Frequency Division Multiplexing) signals sutler serious nonlinear distortion in the nonlinear HPA(High Power Amplifier) because of high PAPR(Peak Average Power Ratio). Nonlinear distortion can be improved by a pre-distorter, but this pre-distorter is insufficient when the PAPR is very high in an OPFDM system. In this paper, a DFT(Discrete Fourier Transform) transform technique is introduced for PAPR reduction. It is especially important to consider the memory effect of HPA for more precise predistortion. Therefore, in this paper, we consider two models, the TWTA(Traveling-Wave Tube Amplifier) model of Saleh without a memory effect and the HPA memory polynomial model that has a memory effect. We design a pre-distorter and an adaptive pre-distorter that uses the NLMS(Normalized Least Mean Square) algorithm for the compensation of this nonlinear distortion. Without the consideration of a memory effect, the system performance would be degraded, even if the pre-distorter is used for the compensation of the nonlinear distortion. From the simulation results, we can confirm that the proposed system shows an improvement in performance.

• 한국정보디스플레이학회:학술대회논문집
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• 2009.10a
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• pp.1604-1607
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• 2009

YAG laser crystallization of Si-based thin film deposited on plastic substrate has been studied. The Si-based thin films as crystallization precursor are with varied hydrogen (H) content. The effect of the H content on the crystallinity of the resulted poly-Si film has been investigated. The experimental results of the poly-Si crystallized by doublefrequency YAG laser shows that the initial dehydrogenation process could be left out if ${\mu}c$-Si was adopted as the crystallization precursor. The YAG laser annealing condition on plastic substrate and the crystallization results have been discussed in the paper.

• The Journal of the Korea Contents Association
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• v.11 no.1
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• pp.350-356
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• 2011

The purpose of this study is to empirically examine how much the electronic clinical trial data management system actually enhances its efficiency. While the development of clinical trial markets highlights the significance of data management with increasing rate of adoption of electronic systems, its effects have not been fully supported with rigorous evidences. Particularly, the adoption rate of electronic clinical trial systems is low in domestic clinical trials markets. This study attempts to analyze the effect of the systems for reminding the importance of e-data management in clinical trials. The measurement indicator is experimented with the time related data collected from a multi-center clinical trial case. The result showed that the speed of the electronic clinical trial processes can be improved. The implication of this study lies in its first attempt to empirically analyze the effect of electronic clinical data management systems. Furthermore, application of the indicator in conjunction with electronic clinical trial processes is expected to facilitate strategic data management.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.27 no.8
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• pp.486-490
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• 2014

$Al_2O_3$ films on silicon carbide were fabricated by Aerosol deposition with annealing temperature at $800^{\circ}C$ and $1,000^{\circ}C$. The effect of thermal treatment on physical properties of $Al_2O_3$ thin films has been investigated by XRD (X-ray diffraction), AFM (atomic force microscope), SEM (scanning electron microscope), and AES (auger electron spectroscopy). Also electrical properties have been investigated by Keithley 4,200 semiconductor parameter analyzer to explain the interface trapped charge density ($D_{it}$), flatband voltage ($V_{FB}$) and leakage current ($I_o$). $Al_2O_3$ films become crystallized with increasing temperature by calculating full width at half maximum (FWHM) of diffraction peaks, also surface morphology is observed by topography measurement in non-contact mode AFM. $D_{it}$ was $2.26{\times}10^{-12}eV^{-1}.cm^{-2}$ at $800^{\circ}C$ annealed sample, which is the lowest value in all samples. Also the sample annealed at $800^{\circ}C$ has the lowest leakage current of $4.89{\times}10^{-13}A$.

• Journal of Distribution Science
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• v.11 no.10
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• pp.17-25
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• 2013

Purpose - This study analyzes the effect of customers' perceived service innovativeness of service centers for electronic goods, on repurchase intentions of customers, using behavior intentions of service centers as a mediator variable. In customer management and customer relationship marketing, service centers can be the most representative customer relationship management departments because they are most closely placed at the interface with customers. In addition, this study intends to investigate if continuous relationship with customers during one-time product-selling can affect their repurchase intentions. Specifically, this research aims to investigate if the expansion of the saturated physical market of the manufacturing business, to intangible service markets, can be competitive enough to satisfy customer needs. Research design, data, and methodology - This study targets college students, and especially those who have computers, digital cameras, or cell-phones, and often use electronic products and services. In order to investigate our hypothesis, we analyzed dates through SEM (structural equation modeling) using SPSS for Windows 18.0 and AMOS 18.0. In addition, we measured Cronbach's α coefficient using SPSS for Windows 18.0 in order to measure reliability. Further, using AMOS 18.0, this research statistically measured convergent validity as well as discriminant validity, and examined mediation models and path models in which service innovativeness leads to customers' repurchase intentions of electronic products. Results - As a result, this research shows that customers' perceived service innovativeness of service centers for electronic goods has significant positive influence on customers' behavior intentions of service centers. In addition, service innovativeness of electronic goods' service centers also has significant positive influence on repurchase intentions of customers. Conclusion - This study investigates the effect of customers' positive relation with the innovativeness of electronic service center on their behavior intention and product repurchase. The more concrete, important results of the study are as follows. Through the mediating effect, the findings of the study suggest that customers' behavior intentions of service centers partially mediate the effect of customers'perceived service innovativeness of service centers for electronic goods on customers' repurchase intentions. This research also provides an insight that the importance of service innovativeness and innovative approaches in managing customers should be recognized in the process of repurchase and service roles of manufacturing business as a way for customer management. As a result, the relationship between customer satisfaction and service quality of service centers for the electronic products is very sensitive. Although previous studies focus on certain aspects of the case for enhancing service innovation (Kim, 2012), this research recommends that the service centers need to understand the customers'desire first and try to adapt to achieve customer satisfaction by being innovative. This innovativeness of service centers would make customers visit them consistently, which in the long run, will also influence their repurchase decisions.

• The Journal of Information Technology
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• v.8 no.2
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• pp.135-148
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• 2005

The purpose of this article is to study on the Comparison of the Basic Law on Electronic Commerce and the Uniform Electronic Transactions Act(UETA). The purpose of th Basic Law on Electronic Commerce is to contribute to the national economy by clarifying the legal effect of transactions by means of electronic messages so as to ensure the security and reliability thereof and to secure fair trade, and further by establishing sound and orderly transactions, and promoting electronic commerce. It is important to understand that the purpose of the UETA is to remove barriers to electronic commerce by validating and effectuating electronic records and signatures. It is not a general contracting-the substantive rules of contracts remain unaffected by UETA. Nor is a digital signature statute. To the extent that a State has a Digital Signature Law, the UETA is designed to support and compliment that statute.

• International Commerce and Information Review
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• v.8 no.1
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• pp.105-123
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• 2006

Electronic Promissory Note started to reducing complexity in paper Promissory Note. In Recent the electronic documents and signature have the same validity as per documents and handwritten signatures. The movement of dematerializing promissory note is becoming common, and the National Assembly proposed Electronic Promissory Note Act of 2001 which is now being discussed in Korea. Especially the Electronic Credits is now becoming the most important means for payment of the business procurement both in on-line commerce and off-line commerce. Electronic Promissory Note has the same legal effect as the promissory note except that the Act provides to the Electronic Promissory Note specially.

• Proceedings of the Korean Magnestics Society Conference
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• 2003.12a
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• pp.60-60
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• 2003

• Proceedings of the Korean Institute of Communication Sciences Conference
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• 2004.11a
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• pp.429-429
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• 2004

• Journal of Electrical Engineering and Technology
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• v.11 no.5
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• pp.1362-1366
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• 2016