• Proceedings of the KIEE Conference
• /
• 2003.07a
• /
• pp.652-654
• /
• 2003

Embedded cost pricing is easy to be applied in the calculation of transmission cost and guarantees perfect recovery of revenue requirement. However, it caused in equity of cost distribution in the restructured electrical market. Though, marginal cost pricing has been studied to be applied to economic signal of members. But it has the cumbersome processes of the revenue reconciliation. This paper presents a new recovery of revenue requirement method that is satisfied with economic signal, using MLF.

• Journal of Electrical Engineering and Technology
• /
• v.7 no.1
• /
• pp.23-33
• /
• 2012

The current paper deals with a new live-line insulator inspection tool system that will be used by the Korea Electric Power Corporation for its 154 kV power transmission lines in 2011. Unlike the existing contact type tools, the developed inspection tool automates parts of the insulator inspection process using a sensor and an actuator. The tool sustains its weight independently, not by a lineman. In addition, the inspection tool measures the insulation resistance of an insulator together with its distribution voltage, thus providing more information for analysis and diagnosis. Such characteristics improve the system's operation efficiency, measurement reliability, and usability. We confirmed its effectiveness through live-line field tests with actual power transmission lines.

• Structural Engineering and Mechanics
• /
• v.31 no.2
• /
• pp.117-135
• /
• 2009

The reflection and transmission of micropolar thermoelastic plane waves at the interface between an elastic solid and micropolar generalized thermoelastic solid is discussed. The interface boundary conditions obtained contain interface stiffness (normal stiffness and transverse stiffness). The expressions for the reflection and transmission coefficients which are the ratios of the amplitudes of reflected and transmitted waves to the amplitude of incident waves are obtained for normal force stiffness, transverse force stiffness and welded contact. Numerical calculations have been performed for amplitude ratios of various reflected and transmitted waves. The variations of amplitude ratios with angle of incident wave have been depicted graphically. It is found that the amplitude ratios of reflected and transmitted waves are affected by the stiffness, micropolarity and thermal distribution of the media.

• Structural Engineering and Mechanics
• /
• v.55 no.4
• /
• pp.839-856
• /
• 2015

A multi-contact tooth meshing model for helical gear pairs considering bearing and shaft deformations is proposed. First, to easily incorporate into the system model, the complicated Harris' bearing force-displacement relationship is simplified applying a linear least square curve fit. Then, effects of shaft and bearing flexibilities on the helical gear meshing behavior are implemented through transformation matrices which contain the helical gear orientation and spatial displacement under loads. Finally, true contact lines between conjugated teeth are approximated applying a modified meshing equation that includes the influence of tooth flank displacement on the tooth contact induced by shaft and bearing displacements. Based on the model, the bearing's force-displacement relation is examined, and the effects of shaft deformation and external load on the multi-contact tooth mesh load distribution are also analyzed. The advantage of this work is, unlike previous works to search true contact lines through time-consuming iterative strategy, to determine true contact lines between conjugated teeth directly with presentation of deformations of bearings and shafts.

• Proceedings of the KIEE Conference
• /
• 2003.07c
• /
• pp.1559-1561
• /
• 2003

In northeast Asia, there will be several important HVDC transmission lines to be established in Korea and China for perspective electric network market. 5500V 4-inches High voltage thyristor can be used in the DC transmission and distribution of electric power system. In this application, many thyristors are connected in series for each thyristor valves. Therefore, the required low reverse-recovery charge QRR and low on-state voltage drop $V_{TM}$ for such thyristor is necessary to this application. In our work, the on-state and off-state voltage performance was simulated by commercial simulation software.

• Proceedings of the KIPE Conference
• /
• 2014.07a
• /
• pp.3-4
• /
• 2014

Power line in electric power tunnel generate heat around during power transmission. Rising temperature inside the electric power tunnel reduces the transmission efficiency of the power line. In this study, trying to understand the change in temperature in the electric power tunnel by forced ventilation and natural ventilation when the temperature rise of the electric power tunnel. The results show that average temperature in electric power tunnel by natural ventilation, forced ventilation is $56.55^{\circ}C$, $23.25^{\circ}C$. Therefore electric power tunnel during power transmission needs cooling or ventilation system.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.16 no.9
• /
• pp.3124-3137
• /
• 2022

We propose a spectral-efficient coordinated direct and relayed transmission (CDRT) scheme for a relay-assisted downlink system with two users. The proposed scheme is based on backscatter communication (BC) and non-orthogonal multiple access (NOMA) technique. With the proposed BC-NOMA-CDRT scheme, both users can receive one packet within one time slot. In contrast, in existing NOMA-CDRT schemes, the far user is only able to receive one packet in two time slots due to the half-duplex operation of the relay. We investigate the outage of the BC-NOMA-CDRT scheme, and derive the outage probability expressions in closed-form based on Gamma distribution approximation and Gaussian approximation. Numerical results show that the analytical results are accurate and the BC-NOMA-CDRT scheme outperforms the conventional NOMA-CDRT significantly.

• Proceedings of the KIEE Conference
• /
• 2009.07a
• /
• pp.420_421
• /
• 2009

The digital TRS(Trunked Radio System) is an excellent alternative for the transmission medium for the DAS(Distribution Automation System). KEPCO(Korea Electric Power Corporation) made the power IT network with digital TRS system. The main function of the radio network is transmitting and receiving information for the DAS. KEPCO's digital TRS is based on TETRA standard. The digital TRS supports data communication for the electric power control and monitoring systems in various ways.

• Proceedings of the KACD Conference
• /
• 2001.11a
• /
• pp.561.2-561
• /
• 2001

Trigeminal sensory nerves relay mechanical, thermal, chemical and proprioceptive information from craniofacial region. Therefore, it is important of dentistry. Trigeminal sensory nucleus consists of principal sensory trigeminal nucleus, spinal trigeminal nuclei, mesencephalic trigeminal nucleus. Transmission of these sensation depends on function and distribution of ion channels.(omitted)

• Proceedings of the KIEE Conference
• /
• 1988.07a
• /
• pp.863-865
• /
• 1988

This paper presents a optimal Var allocation algorithm for minimizing transmission line losses and improving voltage profile in a given system. In this paper, nodal input data is considered as Gaussian distribution with their mean value and their variance. A Stocastic Linear programming technique based on chance constrained method is applied, to solve the var allocation problem with probabilistic constraint. The test result in 6-Bus Model system showes that the voltage distribution of load buses is improved and the power loss is more reduced than before var allocation.