• Journal of the Korean Institute of Educational Facilities
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• v.24 no.1
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• pp.3-10
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• 2017

This study is to analyze the remodeling method of library in terms of space extension method and urban regeneration by repurposing function in unused facilities through case study. In many case of library extension, horizontal extensions are more frequent than vertical extensions, because there are limits to extend vertically due to high live load estimation by book stacks. Extension schemes was organized by new building extension method in connection with existing buildings, attaching method small scaled mass or linear mass to existing building, connecting method a plurality of existing small buildings, vertical extension method on the top of the structure, underground extension method using special structure. Unused facility remodeling to the library, large scaled buildings can be developed completely to the function of the library through the relocation of the space, while small scaled building needs spatial extension. In the case of spatial extension, existing space that was used for other purposes can be used as a reading room or office, avoiding high live load estimation.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.52 no.9
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• pp.500-505
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• 2003

The target of the ULTC(Under Load Tap Changer) control purpose is to minimize the operation number of the tap of the ULTC doing the error voltage which is the difference between the measured bus voltage End the reference bus voltage of the receiving end becomes less than the tolerance limits. The existing ULTC control method controls each ULTC considering only its bus voltage of the receiving end. However, this method did not cons der the coordinated control of the ULTCs of the system. In this paper, I proposed a coordinated control of the ULTC in :he loop power system using the Jacobian matrix. To show the validity of the proposed method, I made simulations for three cases: no action of the ULTC, the control of the ULTC by the existing control method, and the control of the ULTC by the coordinated control among the ULTCs of the system. The simulation result shows that the proposed method has more improvement of the operation of the ULTC than other methods.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2004.05a
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• pp.43-47
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• 2004

Most of LV customer has been composed the 3-phase four wire system distribution system which is supplying simultaneously at the 1-phase & 3-phase load. In this system, the composition of the power apparatus system is simple rather than conventional separation mode of the 1-phase & 3-phase, But due to uneven load unbalance or unclean power quality, various kinds such as do-rating or power losses become an issue. In this paper, we measured and analyzed voltage and current waveform in the field, compared with internationally allowable voltage unbalance limits.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.34 no.6
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• pp.220-229
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• 1985

This paper proposes a new optimal unit commitment algorithm for the rational operation of electric power systems. Especially, the algorithm is improved by considering transmission line capacity limits and load forecasting uncertainty with the consideration of the participation factors of each units, so that the method becomes more reliable and flexible one. The transmission losses are considered by using updated penalty factors obtained from the constant matrixes of the fast decoupled load flow method, the system loads are distributed at each buses, and the several necessary operational constraints are also considered for the purpose of presenting a more practicable scheme. Finally, the effectiveness of the proposed algorithm has been demonstrated by applying to the 23-bus model system.

• Proceedings of the KIPE Conference
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• 2007.07a
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• pp.95-97
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• 2007

This paper studies on operating limit curve of low voltage electric machinery with respect to source voltage variation or sag. Also, it discusses electric machine and compensation equipment design methodology based on voltage quality effect assessment technology. Voltage quality standards, such as SEMI47, CBEMA, ITIC curve are regarded to examine the relation between time constants of load and sagging time of sag generator, the load(low voltage electric machinery) study. Voltage sag characteristics of loads, time constant and sag relation voltage-time operating limits are tested and verified.

• Proceedings of the KIEE Conference
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• 1996.07b
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• pp.746-748
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• 1996

House load operation (HLO) is the Willy of a plant to continue to operate while completely separated from the transmission system. HLO capability is recently adopted as basic design requirement for nuclear power plants, since HLO capability increases the plant availability and power system reliability. However, HLO results in the voltage and frequency transients to motors and pumps. This paper presents the computer simulation results such as the transient speeds, voltages, and control system responses of turbine/g enerator during HLO. This paper also suggests the plant design features required for HLO capability and the transient speed/vlitage limits caused by HLO.

• Proceedings of the KIEE Conference
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• 1996.07b
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• pp.790-792
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• 1996

According to increase in electric power demand, the increasing rate of peak load compared with that of base load grows larger every year. Thus this paper deals with the optimal dynamic dispatch problem due to power rate limits and spinning reserve with loss or without loss. The first is adjusting module for gradual change of generator power by Object-Oriented Programming. The latter is an efficient dispatch module for the consideration of reasonable spinning reserve requirements. The proposed algorithm has been shown efficiency in real power system with loss.

• Proceedings of the KIEE Conference
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• 1996.07b
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• pp.832-834
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• 1996

This paper presents the research on the application of the Hopfield Neural Network to the Economic Load Dispatch problem. The ELD problem has convex cost functions as the objective functions, power balance equation and real power lower/upper limits as the constraints. So we have shown that the possibility of the application of the Hopfield Neural Network to the ELD problem. Through the case study, the simulation results are very close to the numerical method and the dynamic programming method.

• Proceedings of the KIEE Conference
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• 1996.11a
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• pp.133-136
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• 1996

In the paper, an artificial neural network (ANN) approach based on Lagrange multiplier method (Lagrangian ANN) is used to solve an economic load dispatch (ELD) problem. Traditionally ELD problem has one convex cost function as its objective function and nonlinear constraints such as power balance and maximum-minimum limits of real power. In this study, modification is given to the Lagrangian ANN proposed by Gong et all[5] to guarantee the convergence to the optimal solution. Simulation results demonstrate the effectiveness of the proposed method applied to the ELD problem.

• Proceedings of the KIEE Conference
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• 2007.07a
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• pp.33-35
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• 2007

This paper studies on operating limit curve of low voltage electric machinery with respect to source voltage variation or sag. Also, it discusses electric machine and compensation equipment design methodology based on voltage quality effect assessment technology. Voltage quality standards, such as SEMI47, CBEMA, ITIC curve are regarded to examine the relation between time constants of load and sagging time of sag generator, the load(low voltage electric machinery) study. Voltage sag characteristics of loads, time constant and sag relation voltage-time operating limits are tested and verified.