• 정보학연구
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• 제10권2호
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• pp.29-35
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• 2007

In this paper, we describe a study on the relationship between alkaline magenta emulsion manufacture and hardening test of films. The hardeners were prepared by condensation of equimolar amounts of trichlorotriazine with benzene-or naphthalene-based amino or oxy acids at 0 to $5^{\circ}C$ and at pH 7, and used as hardening agents for gelatin. The hardening test of alkaline magenta emulsion was studied at pH 8.5. For example I(R=ONa) had strong hardening properties, I substituted with an aminobenzosulfonate moiety (R=NHC6H4-p-SO3Me where Me = K, Na) was a much weaker gelatin hardener, and when substituted with amino- or oxynaphthalene derivative (II, III) did not harden gelatin at all. Compound with 2 dichlorotriazine groups as IV exhibited hardening properties. The hardener can be used in alkaline magenta emulsion layer of film and showed good hardening effect.

• Transactions on Control, Automation and Systems Engineering
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• 제2권2호
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• pp.98-103
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• 2000

This paper is concerned with a delay-dependent sliding mode scheme for the robust stabilization of input-delay systems with bounded unknown uncertainties. A sliding surface based ona predictor is proposed to minimize the effect of the input delay. Then, a robust control law is derived to ensure the existence of a sliding mode on the surface. In input-delay systems, uncertainties given during te delayed time are not directly controlled by the switching control because of causality prolem of them. They can influence the stability of the system in the sliding mode. Hence, a delay-dependent stability analysis for reduced order dynamics is employed to estimate maximum delay bound such that the system is globally asymptotically stable in the sliding mode. A numerical example is given to illustrate the design procedure.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 1998년도 춘계학술발표회 논문집
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• pp.56-63
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• 1998

A fiber optic gyrocompass for ships was made in consideratino of cost, reliability and convenience. In order to reduce the cost a cheaper fiber sensor was used inthis system. The accuracy was increased by replacing a 180ppr-slit disk with a 1000ppr-encoder. The reliability was also increased by improving the signal processing electronics. This system was made as a heading angle display type for convenience. Although more inexpensive FOG than that of the previous system was used , the accuracy of this compass was increased about 0.5$^{\circ}$. Moreover, it has a very fast warm-up time of about 5minutes. Therefore, this compass can show the prospect of proactical use on ships if it is installed ona stabilizer against the dynamic motion such as rolling and pitching.

• Journal of Electrical Engineering and Technology
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• 제6권3호
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• pp.328-333
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• 2011

A Distribution Automation System (DAS) is operated by monitoring and control of the field statesusing Feeder Remote Terminal Units (FRTUs) installed together withautomatic switches.An optimal placement of automatic switchescan enhanceefficiencyof the operation and restoration, and improve the power supply reliability ofa DAS.This paper proposes an algorithm to decide the optimal placement of automatic switches ina DAS.The proposed algorithm was developed ona DAS witha six sections and three links configuration. The proposed algorithm was provided inaneight-feeder power distribution system.

• 한국동물학회지
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• 제37권4호
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• pp.437-477
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• 1994

The DNA replication of human Iyrnphocvtes was studied using Bromodeo3fyuridine incorporation. The characteristic patterns of dvnamlc banding were analysed. Human chromosomal ONA was synthesized in a segmental but highly coordinated fashion. Each chromosome replicates according to its innate pattern of chromosome structure (bandinsl. R-positive bands are demonstrated as the initiation sites of DNA synthesis, and G-bnads initiate replication after it has been completed in the autosomal R-bands. Many researchers demonstrated that developmental or induced methvlation of DNA can inactivate the associated gene loci. Such DNA methylation can be reversed and specific genes reactivated by treatment with 5-azacvtidine. We treated the hvpomethvlating agent 5-azacvtidine and tested for changes of DNA replication pattern. Treatment with 5-azacytidine causes an advance in the time of replication. These observed changes in timing of replication suggest that DNA methvlation may modify regional groups of genes in concert.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2005년도 춘계종합학술대회
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• pp.969-973
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• 2005

홍콩은 3G MVNO를 제도적으로 도입한 대표적인 사례이다. 홍콩의 규제당국 OFTA는 3G MNO에게 네트워크 용량의 30%에 대해 개방을 의무화하였고, 3G MVNO에게 강력한 권리를 부여하는 라이센스를 발급하였다. 이로써 MVNO 사업자에게 3G 주파수를 보유하지 않고서도 3G 서비스를 제공할 수 있는 기회가 제공되었다. 흥콩의 규제당국은 3G MVNO제도를 도입함으로써 3G 시장의 조기정착, 통신시장의 경쟁활성화, 소비자 혜택의 증대를 기대하였다. 우리나라는 2.3GHz Wibro(휴대인터넷) 라이센스에 네트워크 용량의 30%를 MVNO에 개방해야 한다는 도입근거를 마련함으로써 Wibro 시장의 MVNO제도가 주요 이슈가 되고 있다. 본 연구에서는 홍콩의 3G MVNO제도 도입과정과 제도적 특성을 분석함으로써 국내 Wibro 시장의 MVNO제도 도입에 참고가 될 수 있는 시사점을 제시하고자 한다.

• 정보학연구
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• 제9권1호
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• pp.1-7
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• 2006

In this paper, we describe a study on the relationship between photographic emulsion manufacture and hardening test of films. The hardeners were prepared by condensation of equimolar amounts of trichlorotriazine with benzene- or naphthalene-based amino or oxy acids at 0 to 5$^{\circ}C$ and at pH 7, and used as hardening agents for gelatin. The hardening test of photographic emulsion was studied at pH 5.5. For example I(R=ONa) had strong hardening properties, I substituted with an aminobenzosulfonate moiety (R=$NHC_6H_4-p-SO_3Me$ where Me = K, Na) was a much weaker gelatin hardener, and when substituted with amino- or oxynaphthalene derivative (II, III) did not harden gelatin at all. Compound with 2 dichlorotriazine groups as IV exhibited strong hardening properties. The hardener can be used in photographic emulsion of film and showed very good hardening effect.

• Bulletin of the Korean Chemical Society
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• 제18권7호
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• pp.749-754
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• 1997

Rate constants have been measured spectrophotometrically for the reactions of alkali metal ethoxides (EtOM) with S-p-nitrophenyl 2-thiofuroate (1b) and 2-thiophenethiocarboxylate (2b) in absolute ethanol at 25.0±0.1 ℃. 1b is observed to be more reactive than 2b toward all the EtOM studied. The reactivity of EtOM is in the order EtOK > EtONa > EtO- > EtOLi for both substrates, indicating that K+ and Na+ behave as a catalyst while Li+ acts as an inhibitor in the present system. Equilibrium association constants of alkali metal ions with the transition state (KaTS) have been calculated from the known equilibrium association constants of alkali metal ion with ethoxide ion (Ka) and the rate constants for the reactions of EtOM with 1b and 2b. The catalytic effect (KaTS/Ka) is larger for the reaction of 1b than 2b, and decreases with decreasing the size of the alkali metal ions. Formation of 5-membered chelation at the transition state appears to be responsible for the catalytic effect.

• 전자통신동향분석
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• 제8권2호
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• pp.108-124
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• 1993

개방망은 망 접속을 표준화하여 망을 접근하도록 하는 technical interface의 공개측면과 망이 가지고 있는 망서비스를 공개하여 사용자로 하여금 선택적으로 이용할 수 있게 해주는 망서비스 공개 측면을 모두 고려하여 망구조를 실현해야 한다. 통신망은 망의 서비스 유형 및 일반적인 기능에 따라 음성급 전화망, 데이터망, 전용선망, 이동통신망 및 위성망으로 구분할 수 있으며, 이에 대한 망 접속은 각 망별로 또한 분류될 수 있다. 망서비스는 기술의 발전과 망진화에 따른 기술적인 요인, 고도통신 사업의 다양화에 다른 사업자 요구에 의한 요인, 그리고 시장수요 요인에 의해 계속 발전.진화되어지는 동적인 것이다. 개방망구조는 망서비스와 기술적인 접속을 주요 내용으로 하고 있기 때문에 이것도 역시 계속 진화되는 것으로 해석해야 한다. 본고에서는 개방망의 서비스 측면에서 해당교환 시스팀이나 전송시스팀이 제공가능한 서비스들로서 개방망구조의 서비스메뉴로 표현할 수 있는 것들을 각 망에 대해 자세히 파악하고자 한다. 이번 호에서는 그 첫번째 내용으로서 음성급 전화망에서 개방망서비스로서 국내 교환시스팀과 미국의 ONA 일환으로 BOC가 제공 가능한 것들을 소개한다. 음성급개방망서비스(Voice Grade Open Network Service)는 크게 가입자선측과 중계선측으로 분류 가능하다. 각 분류후에 1) 국내에서 제공가능한 서비스, 2) 여러 BOC가 공통적으로 보유한 서비스, 3) 특정 BOC가 보유한 서비스로 분류 정리하였다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1995년도 춘계학술대회 논문집
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• pp.220-223
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• 1995

Stable polyion-complexed polymeric monolayrers were prepared by spreading perfluoroalkyl monomaleatd copolymers. C$_2$F$\_$8/MA-VE$_2$ and C$_2$F$\_$8/Mv-VE$_3$ on aqueous poly(allylamine) subphase. The monolayer properties have been studied by the surface pressure-area($\pi$-A) isotherms. The C$_2$F$\_$8/MA-VE$_3$containing longer oligoethyleneglycol pendant showed more expaned monolayer phase than the C$_2$F$\_$8/MA-VE$_2$ The polyion-complexed monolayers were transferable on various substrates, and the resulting Langmuir-Blodgett(LB) films were characterized b ET-IR spectroscopy and scanning electron microscopy(SEM) Two-dimensional crosslinking to from a polymer network was achieved by amide formation through heat treatment under vacuum with concurrent removel of perfluoroalkyl tails. SEM observation of this film ona porous membrane filter showed that the four layer film was sufficiently stable to cover the filter pore size of 0.1$\mu\textrm{m}$. The C$_2$F$\_$8/MA-VE$_3$revealed better covering capability than the C$_2$F$\_$8/MA-VE$_2$Immersion of this film in water or in benzend did not cause any change in its appearance and in FT-IR spectra.