• 전력전자학회:학술대회논문집
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• 전력전자학회 2002년도 전력전자학술대회 논문집
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• pp.580-583
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• 2002

An improved MPPT converter with current compensation method for small-scaled PV-applications is presented in this paper. The proposed method implements maximum power point tracking (MPPT) by variable reference current which is continuously changed during one sampling period. Therefore, the power transferred to the load is increased above $9\%$ by the proposed MPPT converter with current compensation method. As a result, the utilization efficiency of Photovoltaic (PV)-panel can be increased. In addition, as it doesn't use digital signal processor (DSP), this MPPT method has the merits of both a cost efficiency and a simple control circuit design. Therefore, it is considered that the proposed MPPT method is proper to low power, low cost PV-applications. The concept and control principles of the proposed MPPT method are explained in detail and its validity of the proposed method is verified through several simulated results.

• 한국콘텐츠학회논문지
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• 제7권12호
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• pp.262-272
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• 2007

SAD(Sum of Absolute Difference) 알고리즘은 동영상 인코더에서 가장 많은 시간이 소용되는 것으로 잘 알려진 움직임 추정에서 가장 자주 계산이 수행되는 알고리즘으로, 동영상 인코딩 수행시간을 줄이기 위해서 우선적으로 최적화 구현되어야 하는 알고리즘이다. 본 논문에서는 VLIW 기반 고성능 DSP 프로세서에서의 조건 분기를 갖는 SAD 알고리즘의 최적 스케줄링 구현 방법을 제안한다. 제안 방법은 먼저 조건 분기를 갖는 중첩 루프를 VLIW 구조가 제공하는 ILP(Instruction Level Parallelism) 능력을 잘 활용할 수 있도록 충분한 크기의 루프 몸체를 가지며 또한 빨리 루프를 탈출 할 수 있는 조건 분기를 갖는 단일 루프로 변환한 후에, 모듈로 스케줄링 기법을 적용하여 VLIW 기반 프로세서에서 최적화 스케줄링 구현을 한다. 제안된 구현 방안을 TMS320C6713에서 구현하고, 코드 크기 및 수행 시간에 대한 성능 분석을 하였다. 구현된 최적화 SAD 루틴은 코드 크기도 크지 않아 임베디드 응용에 적합하며, 이 SAD 구현을 사용한 H.263 인코더가 그렇지 않은 H.263 인코더보다 훨씬 좋은 성능을 보임을 실험을 통해 확인하였다.

• 항공우주시스템공학회지
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• 제1권4호
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• pp.13-21
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• 2007

As one of YHF digital data link technologies, VDL Mode 2 is designed to be an air-to-ground subnetwork of the Aeronautical Telecommunication Network (ATN) based on the Open System Interconnection (OSI) architecture. VDL Mode 2 can be used in ATS Applications especially for CPDLC and ADS. And it is also expected to replace ACARS (Aircraft Communications Addressing and Reporting System) which has broadly been used in AOC for over 20 years. This paper presents the design result of VDL Mode 2 system under AOA (ACARS Over AVLC) environment for the implementation of bit-oriented ATS applications. The system is composed of airborne and ground subsystem. Airborne subsystem consists of VDR, CMU and an aircraft test equipment with CPDLC/ADS client applications for operational test and ground system consists of Ground Station which includes ground VDR and ground communication controller, simple DSP (Datalink Service Processor) and a ground test equipment with CPDLC/ADS server applications.

• 방송과미디어
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• 제1권1호
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• pp.61-74
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• 1996

디지탈 오디오 방송(DAB)과 디지털 텔레비전(DTV), 고선명 텔레비전(HDTV) 방송의 실용화가 다가오면서 대용량의 디지털 오디오 신호를 주관적인 왜곡없이 압축, 복원할 수 있는 고음질 오디오 부호화 방식이 방송음향 기술전반에 응용되고 있다[1][2]. 또한 방송 채널에 있어서도 기존의 스테레오에서 다채널 오디오 시스템으로 진전하면서 가상 현실, 입체음향 등에 필수적인 음장재생 기술이 적용되고 있다[3][4]. 위와 같은 기술은 디지털 오디오 신호처리 기술의 발전이 가져온 결과로 미래의 방송기술을 변화시키고 있다. 본 고에서는 디지털 방송 시스템에 있어서 디지털 신호처리 기술의 응용 분야를 살펴보고 새로운 기술을 소개하기로 한다.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2000년도 전력전자학술대회 논문집
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• pp.645-650
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• 2000

this paper deals with HVDC Light(High Voltage Direct Current) system using space vector PWM(SVPWM) method. Because the system of this paper has d-q control scheme for HVDC Light system. HVDC Light system represented in this paper is capable of controlling active and reactive power independently. For this system. V-I curve and control methods are proposed. Also this paper describes the design of a digital system for applications in power converters such as those that would be used in the next generation of HVDC system. Finally HVDC system is implemented using DSP TMS320C31

• Journal of Power Electronics
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• 제3권1호
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• pp.1-9
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• 2003

This paper presents a performance analysis of typical Auxiliary Resonant Commutation Snubber-assisted three phase voltage source soft switching inverter which can operate under a condition of Zero Voltage Switching (ZVS) using a digital control scheme which is suitable for high power applications compared with resonant DC link snubber assisted soft switching inverter. The system performances of this inverter are illustrated and evaluated on the basis of experimental results.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1994년도 하계학술대회 논문집 A
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• pp.441-443
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• 1994

Modern control theory and high speed switching device such as IGBT have been developed day by day, but it hardly has been applicated practically to the various fields of industry, specially power electronic fields, because there is no cost effective hardware that accommodates modern control theory. Thus, in our study, DSP based ultra high speed general controller which may be exclusively used for power electronic applications is developed.

• Journal of Communications and Networks
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• 제1권2호
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• pp.86-88
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• 1999

The Discrete Fourier Transform (DFT) and the Inverse Discrete Fourier Transform (IDFT) are commonly used in signal processing applications, in particular in digital communication sys-tems using the multi-carrier modulation principle. In such systems an IDFT is computed at the transmitter end, and a DFT at the re-ceiver end. This paper examines a technique of computations, for which only negligible differences appear between the DFT and the IDFT calculations while the number of arithmetic operations re-quired is substantially reduced. This offers significant advantages for the design of an IDFT/DFT processor for Discrete Multitone(DMT) systems.

• KIEE International Transaction on Electrical Machinery and Energy Conversion Systems
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• 제3B권1호
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• pp.52-58
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• 2003

The application of a sliding mode control for improving the dynamic response of an induction motor based speed control system is presented in this paper and provides attractive features, such as fast response, good transient performance, and insensitivity to variations in plant parameters and external disturbance. However, chattering is a difficult problem for which the sliding mode control is a popular solution. This paper presents a new fuzzy-sliding mode controller for a sensorless vector-controlled induction motor servo system to practically eliminate the chattering problem for traction applications. A DSP based implementation of the speed control system is employed. Experimental results are presented using a propulsion system simulator. The performance of the drive is shown to be practically free from chattering.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1992년도 하계학술대회 논문집 A
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• pp.508-511
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• 1992

Modern control theory has been developed day by day, but it hardly has been applicated practically to the various fields of industry, specially power electronic field, because there is no cost effective hardware that accommodates modern control theory. Thus, in our study, DSP based ultra high speed general controller which may be exclusively used for power electronic applications is developed.