• Proceedings of the IEEK Conference
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• 2003.07a
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• pp.597-600
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• 2003

Wireless Internet access shows an early-stage market that is entering a period of strong and sustained growth., reaching almost $40 billion in combined related equipment services by 2008 with equipment and services of nearly equal proportion. This explosive development is possible due to the continued growth of two of the most successful markets in history, the internet and mobile telephony. The number of global wireless internet users will incense from approximately 1.9million in 2001 to 1.3billion by 2006. Technological changes are the main factor in the emergence of what is being called the fourth generation of mobile communications.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2019.05a
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• pp.521-524
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• 2019

The design of photobiological active photosensitizing molecular model for photodynamic therapy has been attracted as a research for the development of cancer treatment, and has been interested in the effective method for cancer treatment and the photosensitizer having more stable wavelength. Furthermore, the development of photosensitizer has been already carried out from the first generation molecule to the third one, and the research of smart photosensitizer as the fourth generation has been requested. As a fact, the selective killing of the only cancer cell is very difficult problem, and the present photodynamic therapy has the problem of killing of the normal cell. So, I have designed the new modelling of photosensitizer having the smart recognizing unit and the magnetic nanoparticle as well as having the several effective recognizing unit. In particular, the new model design of the photosensitizer having lanthanide metal has suggested for the development of photodynamic therapy. The model design of these new photosensitizing molecules will be introduced in the poster section for the new turning point of the development of photosensitizer.

• Journal of the Korean Academy of Esthetic Dentistry
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• v.3 no.1
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• pp.23-31
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• 1995

The All-Bond system is a unique development in the field of adhesive dentistry. It is a universal bonding system that will bond composite to all dental-related surfaces: dentin, enamel, metal alloy (precious and nonprecious), amalgam, porcelain, and composite. It is also the only system that allows use of both the conservative and all-etch techniques. The main purpose of this paper is to explain the features of the All-Bond system. Its chemistry and a working hypothesis are shown as well.

• Proceedings of the Korea Association of Crystal Growth Conference
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• 1996.06a
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• pp.462-487
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• 1996

We report on the fourth and fifth harmonics generations of Nd:YAG laser radiation realized in CsLiB6O10(CLBO). The values of 500 mJ and 230 mJ at 266 nm and 213 nm were obtained from 2200 mJ of fundamental energy. Doping of CLBO has been carried out and the Al doping was found to give rise to an enhancement of mechanical and chemical properties.

• Proceedings of the Membrane Society of Korea Conference
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• 1997.06a
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• pp.143-158
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• 1997

Electrochemical deionization (EDI) offers continuous demineralization at higher water recovery rates (>90%), compared with mixed bed ion exchange, and without the use of chemical regenerants and the associated production of saline waste water. Although EDI technology has been used in some power generation applications, its wider application requires the satisfactory resolution of outstanding capital cost and performance issues. This paper reports on the field evaluation of a new cost-effective EDI technology in a power generation application. The E-Cell System$^{TM}$, which became commercially available in the fourth quarter of 1996, consists of a rugged, modular system, based on a new high-performance EDI stack. Starting in May 1996, a 100 gpm modular EDI pilot system, rated for operation at 100 psi, was evaluated at the TVA Brown's Ferry Nuclear Plant. The feed consisted of Reverse Osmosis (RO) permeate with a conductivity of 4-7 $\mu$S/cm. The pilot system reliably produced 17.8-18.0 M$\Omega$.cm water under design operating conditions, independent. Silica levels were reduced from ca. 50 ppb to 4 ppb, while TOC levels were reduced from ca. 120 ppb to 30 ppb.

• Journal of the Korean Society for Industrial and Applied Mathematics
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• v.19 no.1
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• pp.83-102
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• 2015

The present paper analyses the radiation effects of mass transfer on steady nonlinear MHD boundary layer flow of a viscous incompressible fluid over a nonlinear porous stretching surface in a porous medium in presence of heat generation. The liquid metal is assumed to be gray, emitting, and absorbing but non-scattering medium. Governing nonlinear partial differential equations are transformed to nonlinear ordinary differential equations by utilizing suitable similarity transformation. The resulting nonlinear ordinary differential equations are solved numerically using Runge-Kutta fourth order method along with shooting technique. Comparison with previously published work is obtained and good agreement is found. The effects of various governing parameters on the liquid metal fluid dimensionless velocity, dimensionless temperature, dimensionless concentration, skin-friction coefficient, Nusselt number and Sherwood number are discussed with the aid of graphs.

• Proceedings of the KIPE Conference
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• 2015.07a
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• pp.53-54
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• 2015

A new simple and effective scheme to improve power quality for a grid-connected inverter in distributed generation systems under distorted grid voltages will be presented. The proposed scheme is constructed with two controllers to regulate fundamental and harmonic components separately. In order to accomplish the proposed control scheme, the fourth order band pass filter is used to extract harmonic components from distorted gird voltages. Then, the undesired harmonic components are excellently suppressed by proportional decoupling controller. Experimental results are presented to verify the simplicity and effectiveness of proposed scheme.

• Electronics and Telecommunications Trends
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• v.34 no.6
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• pp.42-50
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• 2019

The fifth generation (5G) wireless technology is expected to be the trigger for the fourth industrial revolution. In particular, 5G ultra reliable low latency communication (URLLC) is expected to lead the wireless automation in vertical domains. In this paper, we analyze use cases, key metrics, and physical layer technologies for 5G URLLC standardized in $3^{rd}$ Generation Partnership Project Radio Access Network (3GPP RAN). Additionally, we discuss enabling RAN technologies towards beyond 5G to support high reliability and low latency.

• Journal of the Korean Society for information Management
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• v.39 no.3
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• pp.217-240
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• 2022

As non-face-to-face elements became important due to COVID-19, the metaverse received social attention, and the MZ generation became the main users of public libraries. In light of this trend, it is necessary to introduce services for the MZ generation, the main users of public libraries, and to provide services tailored to social development. Therefore, this study investigated the perception of the metaverse through questionnaire surveys and semi-structured interviews, centered on the MZ generation, and then proposed a method for applying the metaverse to users in public libraries. According to the results of the study, the direction for the introduction of the metaverse in public libraries was suggested. First, it is necessary to provide basic education and information about the metaverse. Second, it is necessary to provide services that take advantage of the community based on communication. Third, a program that is not constrained by time and space should be provided. Fourth, services by librarians should be provided by enhancing the librarians' expertise on the metaverse. Fifth, services for generation M must be provided.

• Proceedings of the Optical Society of Korea Conference
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• 2001.02a
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• pp.226-227
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• 2001

CsLiB$_{6}$O$_{10}$(CLBO) 단결정은 넓은 광투과 영역, 극자외선 영역에서의 광투과성, 비교적 큰 비선형 광학계수, 높은 레이저 광손상 문턱값 등의 우수한 특성으로 인해 극자외선 영역에서의 파장변환과 고출력 레이저의 파장변환에 매우 활발한 응용이 시도되고 있다. 본 연구에서는 CLBO 단결정을 이용하여 Nd：YAG 레이저의 1064 nm 파장을 4차 조화파인 266 nm 파장으로 변환시키고 광변환 특성을 조사하였다. (중략)