• Journal of Power Electronics
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• v.3 no.2
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• pp.124-138
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• 2003

An advanced simulation model for brushless dc (BLDC) motor drives using Matlab is presented. In the developed model, the dynamic characteristics of speed and torque as well as voltages and currents of pwm inverter components can be effectively monitored and analyzed. Therefore, it can be expected that the developed simulation model can be an easy-to-design tool for the development of BLDC motor drives including control algorithms and topological variations with reduced computation time and memory size.

• Journal of the Korean Institute of Telematics and Electronics
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• v.26 no.11
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• pp.1794-1803
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• 1989

This paper presents and evaluates a distributed routing algorithm for effective routing control in circuit-switched multistage interconnection networks. The proposed method uses the distributed control based on the incividual-switching element control and it is very effective for allowing any broadcast connection from a source to arbitrary number of destinadtions. The performnace of the proposed method is analyzed and evaluated by computer simulation in terms of the normalized average time delays.

• Journal of information and communication convergence engineering
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• v.6 no.1
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• pp.47-50
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• 2008

A novel high channel efficiency transceiver based on a fast acquisition frequency synthesizer has been designed. The direct digital synthesis (DDS) technique is applied and a simple memory look-up table is incorporated to expedite channel acquisition. The technique simplifies the frequency control process in the transceiver and thus reduces the channel switching time. As a result, the channel efficiency is improved. The designed transceiver is ideal for frequency hopping mobile communication applications.

• Proceedings of the KIPE Conference
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• 1999.07a
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• pp.489-492
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• 1999

This paper proposes a control method for three-phase voltage-source PWM converters using only a single current sensor in the DC link. A predictive current controller for the voltage-source PWM converter is used so that all phase currents can be reconstructed in a switching period although one or two of active vectors are applied only for a short time. Compensation of the 2 step delays is also included. In this paper single sensor current control using predictive state observer will be discussed, and investigated experimentally.

• Proceedings of the IEEK Conference
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• 2008.06a
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• pp.721-722
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• 2008

The method for evaluating AF's quality and calculating of AF checking time is proposed in this paper. For the purpose, the fuzzy control method is used. To show the effectiveness, the technique is implemented and the performance is verified on a NEC's 16 bit-general purpose micro-controller. The result shows that although the number of AF checking times is reduced, the receiver can find the best frequency faster.

• 제어로봇시스템학회:학술대회논문집
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• 1988.10a
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• pp.299-304
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• 1988

This paper describes the application of the variable structure control(VSC) concept for the position control of electro-hydraulic servomtor system. The basic philosopy of VSC is that the structure of the feedback control is altered as the state crosses discontinuity surfaces in the state surface with the result that certain desirable properties are achieved. The switching of the control function yields total(or selective) invariance to system parameter variations and disturbances, and closed loop eigen value placement in time-varing and uncertain systems.

• ETRI Journal
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• v.10 no.2
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• pp.32-39
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• 1988

In this paper, we describe an effective trunk loop signal processing method and anlayze execution time of the program in the DTCP (Digital Trunk Circuit Processor) in the TDX-1A digital switching stytem. And we also predict a maximum trunk capacity in the DTCP with respect to scanning period based on the call attempt characteristics which has the Poisson distribution.

• Proceedings of the KSR Conference
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• 2000.11a
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• pp.659-665
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• 2000

EMU Traction Control System has been largely relied on foreign technology until now. In this time, this system is developed by own local technology according to national technology development policy during 3 years. In this paper, the new developed Traction Control System of EMU and its testing results are introduced. The Traction Control System is consisted latest IGBT switching elements and its traction control algorithm is realized by the state-of-the-art technology, vector control. The system is fully tested in various conditions and the quality is well verified in those tests.

• Journal of the Korea Society for Simulation
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• v.10 no.1
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• pp.73-82
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• 2001

The main idea behind the Intelligent Networks (IN) concept is the separation of switching functionality from the service control, in order to meet various service requirements of subscribers and development of new services in time. On the increase of subscriber and for high quality of service, the IN upgrades its service systems, and there are a number of ways depending on the system architecture and the characteristics of services. This paper compares two alternatives, traces the performance of them by means of the simulation technique, and finally puts a rule to select one of them.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.23 no.61
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• pp.33-39
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• 2000

In this paper, we present an algorithm for the multicast routing problem when there exit the cell replication limits of ATM switching nodes. This problem can be formulated as a Degree Constrained Minimum Steiner Tree Problem(DCSP). The proposed algorithm is a modification of the shortest path heuristic originally devised for minimum Steiner tree problem. From the experimental results, it can be seen that our algorithm is efficient to obtain a near optimal solution with comparatively low computational time.