• Journal of the Korean Ceramic Society
• /
• v.37 no.8
• /
• pp.781-786
• /
• 2000

An Er-doped sulfide fiber was drawn, and its spectroscopic properties were analyzed. Compositions of a 1000 ppmwt Er3+-doped core and an undoped clad were Ge30-Ga1-Asg-S61 and Ge30-As8-S62, in at.%, respectively. Refractive index of the core composition was approximately 0.01 high than that of the clad. In order to enhance the mechanical stability as well as to prevent infiltration of impurity ions such as OH-, an UV-curable polymer was used for the coating. The optical loss of a fiber formed directly from a polymer coated core rod without cladding was ∼15 dB/m at 1.06$\mu\textrm{m}$. In the case of a fiber with core/clad structure, the optical loss was so high that the stimulated emission of erbium fluorescence was not evident. It is believed that presence of inhomogeneous core/clad interface and crystalline aggregates precipitated in the clad region were responsible for the high optical loss. On the other hand, fluorescence characteristics of Er3+ embedded in the core region were more or loss deteriorate compared to fiber preform, which is attributed to the redistribution of the Er ions along with the partial crystallization of the core glass during the fiberization process.

• Proceedings of the IEEK Conference
• /
• 1998.10a
• /
• pp.39-42
• /
• 1998

In this paper is design of signal discriminatior system for the third generation mobile telecommunication system (IMT-2000 : International mobile telecommunication service-2000) This system is basically using multiplexing method of CDMA, TDMA and FDMA that this system can be solved third generation systems problems-Frequency bandwidth, international roaming and development new architecture of mobile telecommunication systems. Designed signal discriminator system is perfectly separated three styles multiplexing method signals that more easily, nearly and economically implementation of third generation telecommunication systems. As we develop signal discriminator we will contribute to technical evolution of mobile telecommunication for third generation and stay ahead in the interior technical accumulation in addition to international intercourse as to mobile telecommunication.

• Proceedings of the Korean Society of Broadcast Engineers Conference
• /
• 2017.06a
• /
• pp.18-21
• /
• 2017

클라우드 방송은 서버에서 방송 서비스를 구동한 후 실시간으로 실행 화면이나 정보를 TV 셋톱박스로 전송하는 가상화 방송 서비스로 많은 방송 사업자들의 관심을 끌고 있으며, 이미 상용화를 진행 중인 사업자도 있다. 한국정보통신기술협회(이하, TTA)에서는 클라우드 방송 서비스를 특정 사업자에 종속된 기술이 아닌 개방형 기술로 확장시키고자 "개방형 클라우드 기반 스마트 방송 플랫폼 (TTAK.KO-07.0129)"표준(이하, 클라우드 방송 1.0 표준)을 2016 년 12 월에 제정하였다. 본 논문에서는 클라우드 방송 1.0 표준의 다양한 기술범위 중 표준기반 서비스를 실행하고 서비스와 플랫폼 사이의 인터페이스 등을 정의한 클라우드 방송 1.0 플랫폼 애플리케이션 실행환경에 대한 내용과 그 구현에 대하여 소개한다.

• Korean Management Science Review
• /
• v.23 no.3
• /
• pp.1-11
• /
• 2006

This study investigates empirically on the business analysis of fixed mobile convergence telecommunication service. As for the stage of empirical analysis, the process was carried out in the order elaboration of a test model, selection of sample, empirical analysis and interpretation of result. We report our Preliminary results on the fixed mobile convergence telecommunication service demand pattern forecasting by Bass model. The results show that the fixed mobile convergence telecommunication service may sustain profitability over the next ten years in the market. In conclusion, the practical implication of the result attained by this study is that in order to create a fixed mobile convergence in the korean business world, practical tools such as WiBro service is no less important than fixed service and Mobile service, and that users may be rightfully encouraged to adopt WiBro service.

• Proceedings of the Korea Information Processing Society Conference
• /
• 2003.05b
• /
• pp.1153-1156
• /
• 2003

본 연구에서는 클러스터 VOD 서버에서의 내장형 클라이언트 플랫폼을 선계 및 구현하기 위한 연구를 수행하였다. 클러스터 VOD 서버의 구성과 기능을 살펴보고, 리눅스 환경에서 서버의 기능을 지원하면서 리모콘을 통한 제어와 TV를 통한 출력이 제공되도록 클라이언트를 설계 및 구현하였다. 구현된 시스템에 대한 성능 평가를 통하여 문제점들을 분석하고 대책을 제안한다.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.9 no.2
• /
• pp.49-61
• /
• 1984

The tariff rate of telecommunication networks in Korea is analyzed and the plans for the realization of information society is suggested on this basis. The influence of the cost-down of telecommunication networks construction, the decentralization plan of telecommunication traffics and offer of new services on the decision of telecommunication tariff rate are also descussed here.

• Proceedings of the International Microelectronics And Packaging Society Conference
• /
• 1999.11a
• /
• pp.59-63
• /
• 1999

• International Journal of Quality Innovation
• /
• v.2 no.1
• /
• pp.10-19
• /
• 2001

Following the trend of global telecommunication liberalization, the telecommunication industry in Taiwan will be a star industry and grow up quickly in the future. This study uses questionnaires to survey the implementation issues of total quality management in Taiwan's telecommunication industry. Most of the thirty-nine telecommunication companies surveyed herein are medium-sized with fairly weak quality performance. Advanced quality management training programs (such as experimental design) are seldom implemented and decision-makers do not pay much attention to training programs related to TQM.

• Proceedings of the IEEK Conference
• /
• 2006.06a
• /
• pp.153-154
• /
• 2006

We propose the dynamic channel allocation (DCA) algorithm for multi-cell OFDMA systems to avoid co-channel interference (CCI). The proposed algorithm is utilized not in a centralized, but in a distributed manner which reduces complexity. The simulation results confirm that the number of overlapping allocated subcarriers is reduced and the average SINR of a sub-carrier is increased by this algorithm.

• Proceedings of the Korea Information Processing Society Conference
• /
• 2003.05c
• /
• pp.2017-2020
• /
• 2003

동영상에서 워터마크를 삽입하는 경우 압축 영역에서 수행하는 것이 유리할 경우가 있다. 그러나, 압축 영역에서의 워터마크 삽입은 심각한 화질 저하를 가져올 수 있다. 본 논문에서는 MPEG-2 압축 방식에서 DCT 계수에 워터마크를 삽입하는 경우의 화질 저하에 대한 실험 결과를 제시 하고자 한다.