• Title/Summary/Keyword: 김영기

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Development Status of eLoran System and Its Performance Analysis (eLoran 기술개발 현황과 성능분석)

  • Seo, Ki-Yeol;Kim, Young-Ki;Park, Sang-Hyun;Fang, Tae-Hyun;Lee, Sang-Heon
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • 2018.11a
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    • pp.95-96
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    • 2018
  • This paper deals with the development status of eLoran system which is the best backup position, navigation, and timing (P NT) system of Global Navigation Satellite System (GNSS) and its performance result. I t especially explains the status of eLoran testbed implementation for the eLoran test service, development of eLoran transmitting system, differential Loran (dLoran) system, integrated operation and control system (IOCS), and integrated eLoran/GNSS receiver. The paper discusses about the future plan for the build up test transmitting station and backup P NT service to succeed to the trial operation of eLoran testbed system.

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A Novel Transmission Scheme with Spatial Modulation for Coded OFDM Systems (채널 부호화된 OFDM 시스템을 위한 공간 변조를 이용한 새로운 전송 기법)

  • Hwang, Soon-Up;Kim, Young-Ki;Jeon, Sung-Ho;Kang, Woo-Seok;Seo, Jong-Soo
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.34 no.7A
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    • pp.515-522
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    • 2009
  • In this paper, a novel transmission scheme with spatial modulation is proposed for coded orthogonal frequency division multiplexing (OFDM). The multiple-input multiple-output (MIMO) technique, so-called spatial modulation (SM), divides input data into antenna index and data signals, transmitting data signals through the specific antenna chosen by the antenna index. In order to retrieve data stream at the receiver, SM needs to detect the antenna index which means that data signals are transmitted via a certain antenna. For this reason, it should be guaranteed that channel matrix is orthogonal. For the real environment, a MIMO channel has difficulty in maintaining orthogonality due to spatial correlation. Moreover, the receiver of the conventional SM is operated by hard decision, so that this scheme has a limit to be adopted for practical systems. Therefore, soft-output demappers for the conventional and proposed schemes are derived to detect antenna index and data stream by soft decision, and a novel transmission scheme combined with spatial modulation is proposed to improve the bit error rate (BER) performance of the conventional scheme.

Appropriability Mechanism Strategy for Domestic IT Manufacturing Companies (국내 IT 제조기업의 전유성 확보 전략)

  • Lee, Seung-Jun;Park, Seong-Taek;Kim, Young-Ki
    • Journal of Digital Convergence
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    • v.11 no.11
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    • pp.233-242
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    • 2013
  • Securing the appropriability strategy of R&D funding for technology innovation is very important because R&D needs a lot of time and money. Appropriability means the environmental factors that govern an innovator's ability to capture profits generated by an innovation. Generally appropriability mechanism has five kinds, including patent, secrecy, lead time advantage, complementary sales & service, complementary manufacturing. In this paper, we surveyed domestic software industry professionals about appropriability mechanism strategy, and presented a result of priority of each factor and difference between previous research and this study, using the pair-wise comparison method. The result of study showed that domestic IT manufacturing companies prefer patent better than other appropriability mechanism.

A Study of Heat Transfer in a Horizontal Ice Storage Tube - Inward Freezing Process with Volume Expansion of Ice - (수평 원통형 빙축열조에서의 열전달에 관한 연구 - 얼음의 부피 팽창을 고려하는 내향 응고 실험 -)

  • Lee, J.Y.;Kim, Y.K.;Cho, N.C.;Kim, Y.J.;Yim, C.S.
    • Solar Energy
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    • v.15 no.1
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    • pp.3-11
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    • 1995
  • Heat transfer phenomena during inward freezing process of the water in a horizontal cylinder were experimentally studied. The cooling temperature of a wall more significantly affects the timewise average temperature than the initial superheating temperature of the water. In addition, it was absolved that the timewise average temperature was influenced by the initial volume ratio of the water($V_l/V_{tot}$) at the same temperature conditons. One the other hand, the freezing speed of the upper part in the water-ice interface was quickly progressed due to natural convection. Furthermore, experimental observation showed that the frozen mass fraction($M_s/M_{tot}$) was influenced by the initial volume ratio of the water($V_l/V_{tot}$). It was noted that the frozen mass fraction for each $V_l/V_{tot}$ represented by $Ste^*$ and Fo.

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The Study on Selection and Organization of Computer Education Goal and Content in Elementary School (초등컴퓨터 교육목표와 교육내용의 선정과 조직에 관한 연구)

  • Han, Sun-Gwan;Lee, Soo-Jung;Lee, Jae-Ho;Kim, Young-Gi
    • Journal of The Korean Association of Information Education
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    • v.8 no.3
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    • pp.449-458
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    • 2004
  • There have not been extensive studies on the objectives and contents for computer education, although the computer became a required subject in the 7th Curriculum. Since the success of education greatly depends on the established educational goals, it is important to set up refined objectives related to information communication technology and to educate children accordingly in a systematic way. In this respect, this paper analyses objectives of each elementary subject and curriculums of foreign schools, suggests new objectives for computer education, and discusses methods for selecting contents that are fit to the objectives. Our work can be used as a basis for conducting research on elementary computer education.

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Weight Differences of Patent Valuation Factors by Industries (산업별 특허가치평가 요인의 차이에 대한 연구)

  • Park, Seong-Taek;Leet, Seung-Jun;Kim, Young-Ki
    • Journal of Digital Convergence
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    • v.9 no.3
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    • pp.105-116
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    • 2011
  • The innovation is an important element controlling national economic growth and the competitive power reinforcement of the company. The developed nations concentrate interest on upbringing and investment in knowledge intensive industry and advanced technology base industry for national competitive power reinforcement. I support in particular it as Korean representative industry in the case of the advanced technology base industry positively in the government. Though a patent can become the important competition predominance element of the company by such an advanced technology base industry, this and the proof study in the country to be concerned with are the facts that are not enough now. As for the article of the book, what kind of difference there is in importance by IT and BT industry distinction comment on current events value factors of the patent valuation; of the study is aimed. I derived an importance factor among factors shown in the valuation model of the patent valuation organization and an existing precedent study for comparison analysis in the study and used it. In addition, it was analysis hello it utilized AHP technique, and what kind of difference patent value evaluation important factors showed by IT and BT industry distinction. Analysis, Because patent value evaluation important factors showed a difference by industrial distinction, I appeared.

The Experimental Study on Heat Transfer during Melting Process in the Low Temperature Heat Storage System(Ice on Coil Type) (Ice on Coil형 저온 잠열 축열시스템에서의 용융과정시 열전달에 관한 실험적 연구)

  • Kim, Y.K.;Kim, D.C.;Kim, I.G.;Choi, K.K.;Yim, C.S.
    • Solar Energy
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    • v.19 no.1
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    • pp.19-27
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    • 1999
  • In this study, basic design data which were required for development of highly efficient ice storage system with low temperature latent heat were experimentally obtained. The ice storage system considered in this study was the one that has been widely used in the developed country and called the ice-on-coil type. Using the system, the ice storage performance for various design parameters which were the flow direction and the inlet temperature of the secondary fluid was tested. In addition, the clockwise variation of the heat transfer characteristics of the PCM in the ice storage tank were investigated. During the melting processes in the ice storage tank with several vertical tubes, decrease of the solid-liquid interface area, which was the heat transfer area, between the floating ice and the water made the decreasing rate of IPF less. Also, the total melting energy for the upward flow of the secondary fluid was higher than that for the downward flow during the melting process, but this trend did not appear if the initial temperature of the PCM was $4^{\circ}C$. The average ice recovery efficiency for the upward flow of the secondary fluid was higher than that for the downward flow.

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A Study on the Status of Difficult Patrons and the Effective Response Measures of Public Libraries in Busan (부산지역 공공도서관의 문제이용자 실태와 효과적인 응대방안에 대한 연구)

  • Kim, Young-Kee
    • Journal of the Korean BIBLIA Society for library and Information Science
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    • v.24 no.3
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    • pp.121-134
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    • 2013
  • This study investigated and analyzed the status of difficult patrons, and examined the most effective response measures targeted the public libraries in Busan. A survey on 128 people who served to the public libraries in Busan carried out for analysis of problem behaviors of public library users, and brainstorming and AHP method by 9 librarians for seeking of the effective response plan. This study shows that the most effective response ways for difficult patrons is to enact detailed regulations and the appropriate notification and education to the users about the regulations. In addition, education for communication skills to library staffs should be conducted on a regular basis, like as using positive language, listening techniques, the appropriate response techniques with angry users.

Biochip System for Environmental Monitoring using Nanobio Technology (나노바이오기술을 이용한 환경모니터링용 바이오칩 시스템)

  • Kim, Young-Kee;Min, Jun-Hong;Oh, Byung-Keun;Choi, Jeong-Woo
    • KSBB Journal
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    • v.22 no.6
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    • pp.378-386
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    • 2007
  • Bio-sensing devices, which are basically integrated and miniaturized assay systems consisted of bioreceptor and signal transducer, are advantageous in several ways. In addition to their high sensitivity, selectivity, simplicity, multi-detection capability, and real time detection abilities, they are both very small and require relatively inexpensive equipments. Two core technologies are required to develop bio-sensing devices; the fabrication of biological receptor module (both of receptor development and immobilisation of them) and the development of signal transducing instruments containing signal generation technique. Various biological receptors, such as enzymes, DNA/RNA, protein, and cell were tried to develop bio-sensing devices. And, the signal transducing instruments have also been extensively studied, especially with regard to electrochemical, optical, and mass sensitive transducers. This article addresses bio-sensing devices that have been developed in the past few years, and also discusses possible future major trends in these devices.

Architecture Design for RSIM version 1.3 based Software RS and IM (RSIM 버전 1.3 기반의 소프트웨어 RS, IM 아키텍처 설계)

  • Jang, Wonseok;Kim, Youngki;Seo, Kiyeol
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.18 no.9
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    • pp.2124-2130
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    • 2014
  • The standard for DGPS reference station system defined by RTCM is in the current version of 1.2. This standard currently supports only GPS of the United States. However, the current operating GNSS satellite consisted of not only GPS, but also GALILEO of Europe, GLONASS of Russia, QZSS of Japan, BeiDou of China and so on. Therefore, the existing standard is not able to support them. Accordingly, a new standard in the version of RTCM's RSIM 1.3 is established in order to provide correctional services to GNSS satellites. In this paper, the version of RSIM 1.3 is analyzed and the software for DGNSS reference station architecture supporting the version of RSIM 1.3 is designed.