• Proceedings of the Korea Institute of Applied Superconductivity and Cryogenics Conference
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• 2000.02a
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• pp.29-32
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• 2000

Superconducting transmission cable is one of interesting part in power application using high temperature super-conducting wire as transformance. One important parameter in HTS cable design is transport current distribution because it is related with current transmission capacity and loss. In this paper, we present the calculation theory of current distribution for multi-layer cable using the electric circuit model and in example, calculation results of current distribution and AC loss in each layer of 4-layer HTS transmission cable.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.45 no.4
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• pp.612-615
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• 1996

Audible noise from corona discharge had been identified as one of the most important factors in the design of conductor configurations for high-voltage transmission lines. 500kV and above. Therefore this paper describes audible noise characteristics of 6 X 480mm conductor bundle in KEPRI 765kV Test Line and Corona Cage. Prediction formula for audible(corona) noise on a 765kV transmission Line was developed using this results.

• Current Optics and Photonics
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• v.7 no.3
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• pp.248-253
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• 2023

An efficient global optimization approach for a periodic plasmonic nanoslit array based on extraordinary optical transmission within an acceptable time range is proposed using 𝚀 factor analysis method. The particle swarm optimization is employed as a global optimization tool. The figure of merit is defined as a product of transmission peak value and 𝚀 factor. The design variables are the slit width, height, and period of the slit array, respectively. The optical properties such as transmission spectrum and bandwidth are calculated rigorously using the finite element method.

• Journal of Advanced Navigation Technology
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• v.12 no.3
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• pp.201-207
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• 2008

Design rule of optical transmission link consisted of dispersion management (DM) controlling accumulated dispersion in total fiber length by precompensation and postcompensation, and optical phase conjugator (OPC) positioned at mid-way are proposed. DM schemes investigated in this paper are 2 types depending on the position of precompensation and postcompensation; bi-end type and concentration type. It is confirmed that effective residual dispersion ranges, as a design parameter of optical link, of transmission section from transmitter to OPC and transmission section from OPC to receiver are independence on the positions of dispersion compensating fiber (DCF) accomplishing precompensation and postcompensation, if both DCF position is symmetry with respect to OPC.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.48 no.2
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• pp.117-126
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• 1999

The environmental impact of the KEPCO 765-kV transmission line was studied using a full scale test line in order to develop the design technology. Therefore this paper describes an environmental design summary of the audible noise, hum noise, wind noise, radio interference, TV interference and electric field measurement from the KEPRI 765-kV double circuit transmission test line with a bundle of $6-480mm^2$ conductors per phase. The analysis of the test results shows that 6-Rail and 6-Cardinal conductors bundle satisfy the audible noise criterion & TV interference under the stable rainy weather condition and the radio interference level under the fair weather. And the other items are also agreed with the design level criterion for KEPCO 765-kV transmission line.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.14 no.5
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• pp.1043-1053
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• 1994

This study suggests a practical but rational approach for the development of reliability-based LRFD criteria for transmission towers under wind and ice loadings in Korea. Based on available statistical data on wind speed and icing on transmission lines in Korea, the design wind and ice loads are obtained by Monte Carlo Simulations. In the study, the AFOSM reliability method and an Importance Sampling Technique are used for the element and system reliability evaluation of actual transmission towers. Based on the selected target reliabilities, a set of load and resistance factors for the LRFD criteria are calibrated using the AFOSM and the code optimization technique.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.12 no.5
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• pp.25-30
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• 2012

It is important to detect dangerous objects which are intentionally abandoned in public places. Nowadays visual surveillance system is required to enhance the performance in two ways : high resolution and wireless linking ability. In this study the design of visual surveillance system is newly proposed to detect abandoned objects for social security purpose based on wireless high resolution image transmission technology. Also, to enhance PED, PAT performance, the tracking algorithm is included in the previous visual surveillance software scheme. By implementing proposed design scheme on the real wireless high resolution image transmission system, the effectiveness of the overall system is shown with the transmission performance of 4.0 Gbps speed.

• Journal of Mechanical Science and Technology
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• v.18 no.1
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• pp.82-91
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• 2004

This article deals with a minimum energy control law of S-CVT connected to a dc motor. The S-CVT can smoothly transit between the forward, neutral, and reverse states without any brakes or clutches, and its compact and simple design and its relatively simple control make it particularly effective for mechanical systems in which excessively large torques are not required. And such an S-CVT equipped power transmission has the advantage of being able to operate the power sources in their regions of maximum efficiency, thereby improving the energy efficiency of the transmission system. The S-CVT was intended to primarily for use in small power capacity transmissions, thus a dc motor was considered here as the power source. We first review the structure and operating principles of the S-CVT, including experimental results of its performance. And then we describe a minimum energy control law of S-CVT connected to a do motor. To do this, we describe the results of an analysis of the dynamics of an S-CVT equipped power transmission and the power efficiency of a DC motor. The minimum energy control design is carried out via B-spline parameterization. And we show numerical results obtained from simulations illustrate the validity of our minimum energy control design, benchmarked with a computed torque control algorithm for S-CVT.

• The Transactions of the Korean Institute of Power Electronics
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• v.3 no.1
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• pp.77-84
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• 1998

This paper describes a control system design for the transmission STATCOM by applying a no-linear state feedback, and the performance analysis of the control system by simulations and scaled-model experiments. A mathematical model for the STATCOM was derived using a 3-phase equivalent circuit and a perturbation state equation with respect to a typical operating point. A transfer function to describe the dynamics of STATCOM was derived by considering nonlinear state feedback. A controller design was completed by analyzing the feedback system stability with root locus method. The performance analysis of the conceived control system was verified by simulations with the EMTP and experiments with scaled model, assuming that the STATCOM is connected to an 154kV transmission system. The results show that the conceived control system has excellent performance to control the reactive power of the transmission system.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.25 no.9B
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• pp.1518-1526
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• 2000

This paper proposes an optical transmission link design method based on an optimum compensation scheme using dispersion compensating fiber (DCF), so that high-speed long-distance optical transmission would be possible over the conventional standard single mode fiber (SMF) link. The proposed design method provides the maximized transmission distances according to the signal speeds, where the amplifier spacing and repeater spacing are optimized wit respect to self-phase modulation(SPM) due to fiber nonlinearity and amplified spontaneous emission (ASE) noises caused by optical amplifies. It is also shown that there exists an optimum input signal power range balancing the effects of ASE noise and SPM for the given amplifier spacing and repeater spacing.