• Kyungpook Mathematical Journal
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• v.56 no.2
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• pp.357-366
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• 2016

In this paper, deferred statistical convergence is defined by using deferred $Ces{\grave{a}}ro$ mean instead of $Ces{\grave{a}}ro$ mean in the definition of statistical convergence. The obtained method is compared with strong deferred $Ces{\grave{a}}ro$ mean and statistical convergence under some certain assumptions. Also, some inclusion theorems and examples are given.

• Journal of the Korea Convergence Society
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• v.9 no.7
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• pp.205-211
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• 2018

The purpose of this study is to propose a strategy to educate the core contents of various major fields in practical and convergent ways in universities in order to prepare for the 4th industrial revolution era. First, convergence field is established in the university curriculum in addition to the existing major and the liberal arts field. Second, convergence courses are created in connection with job ability, which are major curriculum but only for students in other departments. Third, convergence courses are organized in the form of module curriculum, which is a small-sized and independent curriculum consisting of 4 courses. D University, one of the local private universities in Korea, has provided such convergence module education since 2016, and satisfactory results have been obtained in the course enrollment rate and the course evaluation, etc. By combining these convergence modules in various ways, it is possible to easily create customized majors required and designed by local companies at low cost.

• ETRI Journal
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• v.31 no.6
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• pp.765-769
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• 2009

In this paper, we present the fabrication of 40 Gb/s traveling-wave electroabsorption modulator-integrated laser (TW-EML) modules. A selective area growth method is first employed in 40 Gb/s EML fabrication to simultaneously provide active layers for lasers and modulators. The 3 dB bandwidth of a TW-EML module is measured to be 34 GHz, which is wider than that of a lumped EML module. The 40 Gb/s non-return-to-zero eye diagram shows clear openings with an average output power of +0.5 dBm.

• Korean Journal of Optics and Photonics
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• v.32 no.5
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• pp.220-229
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• 2021

The optical characteristics of high-power direct-lit white light-emitting diode (LED) lighting were investigated, where a quantum dot (QD) film was adopted to enhance the color-rendering index (CRI). The transmittance of the diffuser plate and the concentration of the QD film were varied in this study. The color coordinates and the correlated color temperature (CCT) did not show any appreciable change, while the CRI values increased slightly as the transmittance of the diffuser plate decreased. The investigated optical properties were nearly independent of the viewing angle, and the luminance distribution was close to Lambertian. The CCT decreased from approximately 6000 K to approximately 4000 K as the concentration of the QD film increased from 0 to 7.5 wt%, which was due to the enhanced red component in the emission spectrum. The CRI increased to approximately 95 for some optical configurations of the lighting. These results demonstrate that glare-free, color-changeable, high-rendering LED lighting can be realized by using a combination of a diffuser plate of appropriate transmittance and a red QD film.

• Journal of Digital Convergence
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• v.9 no.4
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• pp.169-179
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• 2011

The purpose of this study are as follows. First, to analyze digital convergence level of convergence generation to demographic variables. Second, the convergence level to digital device and using frequency to digital service. Third, the convergence level to digital service and using frequency to digital service. The research methods FGI, the interview with IT expert group and survey. The results of research are as follows. First, 30 aging, expert group, higher education group over graduate school are actively using and participated. Second, high level of convergence device are smart-phone, tablet PC, net-book are in order. high level of convergence service are SNS service, twitter, uee, portal messenger and app store, e-Book, web hard are in order. Third, The convergence generation enjoying app-store of smartphone, wireless game and more participating facebook/cyworld twitter, Portal, internet community.

• Composites Research
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• v.31 no.5
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• pp.186-191
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• 2018

Condition and properties of composites with different chemical structure of epoxy matrix were observed after saline solution treatment. Epoxy was used as matrix and the flexibility was controlled by using 2 typed-epoxies and 3 types hardeners (amine, acid anhydride and amide). Saline water treatment was conducted with 6 wt% NaCl solution at $60^{\circ}C$ for 0, 15, and 30 days. Cross section was observed and interfacial and mechanical and properties was evaluated. Amine type exhibited the highest crosslinking density and mechanical and interfacial properties whereas water absorbance was lowest. It is because that the water molecules can be hardly penetrate into the epoxy matrix or the interface between epoxy and glass fiber and it leads to saline water resistance of composites.

• The Mathematical Education
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• v.53 no.3
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• pp.357-381
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• 2014

This study analyzed the cases of three teacher communities participating in an innovative professional development program and clarified the characteristics and the process of lessons for mathematics-oriented convergence that were developed and applied during the program. Each of the teacher communities designed and implemented lessons according to the context of each community and the concept of lessons for mathematics-oriented convergence were developed and refined. The lessons developed by the three teacher communities were characterized as convergence problem posing lessons using technology, convergence of various subject content focused on mathematical concepts through team teaching, and convergence lessons according to students' achievement levels. The program contributed to teacher community activities by proving sustainable professional development in the area of convergence education, a connection between the content of their professional development and the context of the field, and opportunities for active participation in the process of developing and implementing the convergence lessons.

• Communications of the Korean Mathematical Society
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• v.33 no.2
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• pp.677-693
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• 2018

In this work, we generalize a family of optimal eighth order weighted-Newton methods to Banach spaces and study its local convergence to approximate a locally-unique solution of a system of nonlinear equations. The convergence in this study is shown under hypotheses only on the first derivative. Our analysis avoids the usual Taylor expansions requiring higher order derivatives but uses generalized Lipschitz-type conditions only on the first derivative. Moreover, our new approach provides computable radius of convergence as well as error bounds on the distances involved and estimates on the uniqueness of the solution based on some functions appearing in these generalized conditions. Such estimates are not provided in the approaches using Taylor expansions of higher order derivatives which may not exist or may be very expensive or impossible to compute. The convergence order is computed using computational order of convergence or approximate computational order of convergence which do not require usage of higher derivatives. This technique can be applied to any iterative method using Taylor expansions involving high order derivatives. The study of the local convergence based on Lipschitz constants is important because it provides the degree of difficulty for choosing initial points. In this sense the applicability of the method is expanded. Finally, numerical examples are provided to verify the theoretical results and to show the convergence behavior.

• Journal of Engineering Education Research
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• v.17 no.6
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• pp.53-61
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• 2014

This study aims to identify on the possibility of the convergence education in engineering. Delphi survey on a panel of experts was chosen to be the main methodology for this study, drawing the main factors of convergence education in engineering. From Oct. 10 to Nov. 25, 2013, a three-round Delphi survey was implemented to collect data. A panel of eighteen experts were involved in this survey. For statistical processing, descriptive statistics including frequency, percentage, mean and standard deviation were carried out along with internal reliability test on the survey instrument. First, the possible convergence of disciplines in engineering were found to Design, Industrial design, ICT, Health care services, Video media, Business and Administration, Organizational psychology, Sociology, Humanities and Aesthetics. Second, the convergence education factors to be most important demanded creativity, idea generation techniques such as the expression of thought communication skills, technical expertise in the field per line, understanding of basic knowledge, verification of common elements among different disciplines, understanding of other disciplines fusion in engineering, artistry and imagination, etc. Third, requirements for the talented person of convergence were the open mind and enthusiasm, creative imagination, accept the opinions of others, skills capacity as a creative expression, and challenges. Above-mentioned requirements are found to be the necessary elements for convergence education.

• ETRI Journal
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• v.31 no.6
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• pp.653-659
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• 2009

We have investigated the channel protection layer (PL) effect on the performance of an oxide thin film transistor (TFT) with a staggered top gate ZnO TFT and Al-doped zinc tin oxide (AZTO) TFT. Deposition of an ultra-thin PL on oxide semiconductor films enables TFTs to behave well by protecting the channel from a photo-resist (PR) stripper which removes the depleted surface of the active layer and increases the carrier amount in the channel. In addition, adopting a PL prevents channel contamination from the organic PR and results in high mobility and small subthreshold swings. The PL process plays a critical role in the performance of oxide TFTs. When a plasma process is introduced on the surface of an active layer during the PL process, and as the plasma power is increased, the TFT characteristics degrade, resulting in lower mobility and higher threshold voltage. Therefore, it is very important to form an interface using a minimized plasma process.