• Proceedings of the KIEE Conference
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• 1984.07a
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• pp.92-95
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• 1984

This paper describes a general method for the design of variable structure Model-Following Control systems (VSMFC). This design concept is developed using the theory of variable structure systems and slide mode. The feasibility and the advantages of the method are illustrated by applying it to a 1000 MWe Boiling Water Reactor. The control is studied in the range of 85 - 90 % of rated power for load-following control. A set of 12 nonlinear differential eq. are used to simulate the total plant. A 6th order linear model has been developed from these equations at 85% of rated power. The obtained controller is shown by simulations to be able to compensate for a plant parameter variation over a wide power range.

• Journal of Institute of Control, Robotics and Systems
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• v.13 no.2
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• pp.154-162
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• 2007

In this paper, we propose a new AC-DC converter control method to comply with harmonics regulation(IEC 61000-3) effective for the inverter system of an air conditioner whose power consumption is less than 2,500W. There are many different ways of AC-DC converter control, but this paper focuses on the converter control method that is adopting an input reactor with low cost silicon steel core to strengthen cost competitiveness of the manufacturer. The proposed control method controls input current every half cycle of the line frequency to get unit power factor and at the same time to reduce switching loss of devices and acoustic noise from reactor. This kind of converter is known as a Partial Switching Converter(PSC). In this study, theoretical analysis of the PSC has been performed using Matlab/Simulink while a 16-bit micro-processor based converter has been used to perform the experimental analysis. In the theoretical analysis, electrical circuit models and equations of the PSC are derived and simulated. In the experiments, micro-processor controls input current to keep the power factor above 0.95 by reducing the phase difference between input voltage and current and at the same time to maintain a reference DC-link voltage against voltage drop which depends on DC-link load. Therefore it becomes possible to comply with harmonic regulations while the power factor is maximized by optimizing the time of current flow through the input reactor for every half cycle of line frequency.

• Nuclear Engineering and Technology
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• v.17 no.3
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• pp.185-192
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• 1985

The fissile content of PWR spent fuel is higher than that of natural uranium which is normal fuel for CANDU type reactor. Investigated are the concepts of PWR spent fuel utilization in CANDU type reactor to diversify uranium resource and partially to solve storage problems of PWR spent fuel being gradually accumulated. Nuclear characteristics of uranium-plutonium mixed oxide fuel loaded in CANDU type reactor are analysed using the WIMS/D computer code. In this study, analyses are solely carried out upon the current CANDU type reactor design without changingany reactivity control devices.

• 제어로봇시스템학회:학술대회논문집
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• 1991.10b
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• pp.1693-1698
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• 1991

An axial dispersion model is developed for the slim reactor employed in the LDPE autoclave process so that imperfect mixing caused by large L/D ratio (10-20) may be quantified by Peclet number. The model is then used to investigate the effect of mixing on the reactor performance represented by the monomer conversion, the reactor temperature, the molecular weight, and the polydispersity. In addition, the existence of steady state multiplicity is identified with the initiator feed concentration or the feed temperature as the bifurcation parameter. The effects of the initiator feed concentration and the feed temperature are also examined.

• The KSFM Journal of Fluid Machinery
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• v.19 no.3
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• pp.10-13
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• 2016

The wet-air oxidation in gravity pressure reactor is effective for organic waste treatment with energy saving under high pressure and high temperature. But its oxidation control is difficulty because its multi-phase flow characteristics is very complicated. The flow characteristics of an oxidizer feed section in the gravity pressure reactor were investigated using numerical method which are verified by comparison with experimental results. In this study, the results showed that the flow rate of oxidizer have an effect on the generation of bubble around feed section.

• The Transactions of the Korean Institute of Power Electronics
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• v.6 no.6
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• pp.489-497
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• 2001

The proposed dobule phase locked loop and active multiple interphase reactor are used to eliminate the circular current and the voltage ripples caused by the system parameter unbalance of parallel connected UPSs. In this paper, digital controller for the dobule PLL and active interphase reactor is implemented with ADSP21061 as an aspect of functional convenience.

• 제어로봇시스템학회:학술대회논문집
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• 2001.10a
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• pp.100.3-100
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• 2001

This article deals with the development of a mathematical model for the finishing polycarbonate polymerization process using a horizontal rotating disk-ring reactor with counter-current gas sweeping and the performance analysis of the reactor system by using the model. Here we intend to propose a model describing the reactor system consisting of two phases, in which by-product phenol is removed from the polymer of high molecular weight compatible with the products of commercial grades. The vapor phase is represented by a tanks-ln-series model while the polymer melt phase is regarded as a plug flow reactor.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2012.04a
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• pp.907-910
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• 2012

Since the inner barrel assembly of the Advanced Power Reactor 1400 reactor vessel is a new design feature introduced instead of CEA(control element assembly) shroud assembly, the inner barrel assembly can be a significant object of structural integrity assessment. This paper covers the structural responses of top plate, which is a component of the inner barrel assembly, against the deterministic hydraulic load induced by pump pulsation and the random hydraulic load induced by turbulence of coolant. The top plate responds to the deterministic hydraulic load more than to the random hydraulic load and shows enough structural integrity. The results of this paper will be important basis for the selection of instruments and measurement location.

• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 1994.05a
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• pp.130-137
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• 1994

As a part of developing engineering simulator for CANDU 6 nuclear power plants, present paper gives the tentative simulation results of reactor and turbine power transients including reactor-follow-turbine operation. One point kinetics equations are used for neutron dynamics, iodine and xenon loads. To calculate time-dependent high and low pressure turbine powers and grid frequency deviation, simple first order differential equations are used. In addition, control logics (reactor regulating system, demand power routine, and unit power regulator) used in the plant's process computers have been referenced.

• Journal of the Korean Institute of Telematics and Electronics
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• v.6 no.1
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• pp.1-11
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• 1969

Reactor power frequency spectrum measurements at various power levela-OW, 1KW, 50KW, 100KW were made with TRIGA-MARK-II. An ion chamber was exposed to reactor flux, and the fluctions in its output current were analyed in a tunable bandpass filter to get the frequency spectrum of these fluctuation. The measured frequency spectrum of pile determined the modules of modules of zero power transfer function and indicated a prompt neutron mean life time of (7.90$\pm$1.62)X10 sec based on effective delayed neutron faction of 0.0075. The absolute value of reactor power obtained by noise analysis agreed within 5% with the power meter indication at the power below 10Kw.