• Proceedings of the KIEE Conference
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• 2008.04b
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• pp.13-15
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• 2008

국내 접지시스템 설계시 가장 널리 사용되는 것은 ANSI/IEEE Std. 80-2000이나 국내 접지설계 환경의 적정성 여부는 검토되고 있지 않다. 따라서, 본 논문에서는 국내 접지설계 환경을 고려한 새로운 접지도체의 굵기 산정방법과 접지도체의 위험전압 산정방법, 접지도체의 Grid간격 산정방법을 적용하여 ANSI/IEEE Std.80-2000을 보완한 새로운 접지시스템 설계 방법을 제시하였다.

• Proceedings of the KIEE Conference
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• 2008.04b
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• pp.31-33
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• 2008

본 논문에서는 국내 접지설계 환경의 적정성 여부를 검토하여 ANSI/IEEE Std.80-2000을 보완한 새로운 접지시스템 설계방법을 이용하여 접지설계를 검토하였으며, ANSI/IEEE Std. 80-2000 Annex B의 사례연구를 통해 기존방식과 비교 검토하여 신뢰성과 경제성을 검증하였다.

• Proceedings of the KIEE Conference
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• 2006.07a
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• pp.112-114
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• 2006

과거 국내 접지설계는 요구 접지저항값 중심의 설계로 위험전압에 대한 접근은 미흡한 실정이었으나 최근에는 국외에서 중요시하고 있는 접지계의 안전전압에 중점을 둔 접지설계가 이루어지고 있다. 이에 시화호 조력발전소 건설공사의 접지설계를 모델로 하여 최근접지설계 기법을 정리하였다.

• The Proceedings of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.4 no.1
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• pp.46-53
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• 1990

GIS(Gas-Insulated Switchgear)형 옥내변전소에 있어서 접지계의 구성은 접지도체를 포설할 수 있는 면적이 협소하기 때문에 특별한 설계방법이 요구된다. 본 논문에서는 접지망의 전위해석과 축소형 변전소의 접지계 설계기법을 제시하였고, 아울러 컴퓨터 시뮬레이션을 위한 프로그램을 작성하고 그 시뮬레이션 결과를 측정치와 비교하여 프로그램의 타당성을 입증하였다.

• Proceedings of the KIEE Conference
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• 1998.07c
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• pp.1179-1181
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• 1998

This paper describes the induced voltage of sheath on 154kV transmission power cable in multi fault states. Simulation was carried out to obtain the induced voltage of sheath according to change of, fault angle and grounding resistance using EMTP. Modeling of cable system is also established in EMTP to analyze. The simulation results can be useful reference to design cable system in power system.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.19 no.1
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• pp.57-62
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• 1983

The galvanic anodes have three kinds of Zn alloy anode, Al alloy anode and Mg alloy anode, which are widely used in cathodic protection for all metal structures in water or under ground. This paper to be used for designing of the grounding cell has reached the following conclusion as the results of an experimental study on the characteristics of such galvanic anodes for corrosion protection of pipings: 1) Zn alloy anode was the best when the specific resistance of the environment was bellow 1000 $\Omega$.cm, and when above 1000 $\Omega$.cm, Mg alloy anode to be used for designing of the grounding cell was the best. 2) Al alloy anode was better than Mg alloy anode for grounding cell when the specific resistance was bellow 500 $\Omega$.cm, but the Al alloy anode in all the environments reduced the characteristics of galvanic anode to the lower grade than those of Zn alloy anode. 3) Each impressed voltage (E) of the anodes at which drainage current density ($\rho$) begins rapidly increasing is quantitatively presented as follows: \circled1 E sub(Zn)=log (4.9465/$\rho$super(0.0639))+11$\times$10 super(-6)$\rho$super(0.8923i) \circled2 E sub(Al)=log (4.9306/$\rho$super(0.0525))+13$\times$10 super(-6)$\rho$super(0.9314i) \circled3 E sub(Mg)= log (3.7086/$\rho$super(0.0988))+181$\times$10 super(-6)$\rho$super(0.5406i) 4) The empirical equations between the drainage current density (i) and impressed environment are modeled as the following type. logi=g+root(n.E+r)(g,n,r; constants)

• The Journal of Korean Institute of Communications and Information Sciences
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• v.28 no.11A
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• pp.921-928
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• 2003

This paper propose a new design of directional couplers with the high directivity. The directional coupler is used to check and verify the power, frequency and antenna reflection of a signal at transmission station for the mobile communications. The performance index of the directional coupler is to which the coupling is strong to reduce the effect on the transmitted power and the directivity is high to suppress the interference of the reflected signals and reduce the nor in the communication. Then, the architectures to gain the high directivity and the studies to get the strong coupling have been proposed However, the conventional architectures lot the high directivity and strong coupling have the directivity by about 20㏈ and the difficulty to achieve the higher directivity than 40㏈ suitable for IMT-2000 [1]. This paper proposes an architecture of the directional coupler which is based on the grounding composed of the strip lines and the comparison results with the conventional directional couplers. The comparison results show that the proposed directional coupler has the directivity more than 40 ㏈ and is adequate for the 2.05GHz IMT-2000

• Proceedings of the KSR Conference
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• 2007.05a
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• pp.236-241
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• 2007

DC feeding system is mainly floating but the rail potential and the leakage current are created because of long parallelism between rails and ground. Rail potential causes electric shock to human and leakage current causes electrolytic corrosion to nearby the buried metals. Therefore the design technologies to reduce, protect and monitor these effects are important recent DC feeding system. Normally during designing DC feeding system in terms of rail potential and leakage current, there are about 10 parameters. Four design parameters among those is analysed based on propagation theory that is utilized in order to simulate grounding system.

• Korean Institute of Interior Design Journal
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• v.16 no.6
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• pp.36-46
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• 2007

Regeneration of old buildings is one of the most imperative responses to the 21th century issue of sustainable urban architectural environment. In particular, creative circulation of generation which conversion means highlights the conversion as a new design method. In this study, by examining buildings built over the last decade, the mutual relationship between old elements of existing buildings and new elements of newly required functions was analyzed and types of relationships such as 'alien insertion', 'mediate intervention', 'endogenous expansional enveloping', 'contrastive confliction' and 'over-layering' were defined. In addition, design strategies including the paradoxical curio, fore-grounding and unification were derived from each relationship. Finally, according to the relation type and design strategy, this study suggests several features of conversion design; (1) maximization of symbolism using unfamiliarities - emphasizing futuristic or contextual symbol with intentional contrasts by preserving the work or using contemporary addition; (2) time confusion using neutral space - meeting the need by harmonizing and cooperating existing elements and new elements; (3) mutual emphasizing by individualization - revealing differences between old and new for an aesthetical tension; (4) synchronism by constructional combination - making the one unity of different layers; (5) expansion by enveloping - experience of visual reverse and creation of extra space by roofing above building groups. The reconversion should be continuously researched in the future since conversion is a sustainable design method for the future of architecture.

• Proceedings of the KIEE Conference
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• 2000.07a
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• pp.221-223
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• 2000

This paper describes the design of SVC fuzzy logic controller (SVC-FLC) using adaptive evolutionary algorithm and we tuned the gain of input-output variables of SYC-FLC using it. We performed the nonlinear simulation on an single-machine infinite system to prove the efficiency of the proposed method. The proposed SYC-FLC showed the better performance than PD controller in terms of the settling time and damping effect, for system operation condition used in evaluating the robustness and three phase grounding default in cases of nominal loading used in tuning SVC-FLC for a single-machine infinite system.