• 대한전기학회논문지
• /
• 제35권12호
• /
• pp.541-554
• /
• 1986

This paper presents the results of driving performance analysis of permanent magnet synchronous motor using a microprocessor based control system. The system consists of three phase power transistor inverters, three phase controlled rectifier, three central processing units, and sensors. The three CPUs are, respectively, used to generate PWM control signals for the inverter generating three phase sine wave, to generate the gate control signals for firing the converter, and to supervise other two CPUs. The supervisor is used to compute PI control algtorithm to three phase reference sine wave for the inverter. It is also used to maintain a constant voltage frequency ratio for the converter operating as a constant torque controller. The inverter CPU retrieves precomputed PWM patterns from look up tables because of computation speed limitations found in almost available microprocessors. The converter CPU also retrieves precomputed gate control patterns from another look-up tables. For protecting the control ststem from any damage by extraordinary over currents, the supervisor receives the data from current sensor, CT, and break down the CB to isolate the circuits from source. A resolver has a good performance characteristics of overall speed range, especially on low speed range. Therefor the speed control accuracy is impoved. The microprocessor based PM synchronous motor control system, thus, has many advantages such as constant torque characteristics, improvement of wave, limitation on extraordinary over currents, improvement of speed control accuracy, and fast response speed control using multi-CPU and look-up tables.

• 전자공학회논문지B
• /
• 제33B권5호
• /
• pp.41-51
• /
• 1996

In this paper, anew parallel processing system based on a cluster architecture which provides scalability of a parallel processing system while maintains shared memory multiprocessor characteristics is proposed. In recent days low cost, high performnce microprocessors have led to construction of large scale parallel processing systems. Such parallel processing systems provides large scalability but are mainly used for scientific applications which have large data parallelism. A shared memory multiprocessor system like TICOM is currently used as aserver for the commercial application, however, the shared memory multiprocessor system is known to have very limited scalability. The proposed architecture can support scalability and performance of the parallel processing system while it provides adaptability for the commerical application, hence it can overcome the limitation of the shared memory multiprocessor. The architecture and characteristics of the proposed system shall be described. A proprietary hierarchical crsossbar network is designed for this system, of which the protocol, routing and switching technique and the signal transfer technique are optimized for the proposed architecture. The design trade-offs for the network are described in this paper and with simulation usihng the SES/workbench, it is explored that the network fits to the proposed architecture.

• 한국해양공학회지
• /
• 제23권2호
• /
• pp.8-17
• /
• 2009

This paper presents an adaptive tracking control method for a welding mobile manipulator with several unknown parameters such as the last length of the manipulator, the wheel radius and the distance from the center to the wheel. The mobile manipulator consisted of the manipulator and the mobile-platform. Kinematic modelings for the manipulator and the mobile-platform with several unknown parameters were produced. The tracking error vectors for the manipulator and the mobile-platform were defined. These adaptive controllers were designed based on the Lyapunov function to guarantee the stability of the whole system when the mobile manipulator performs a welding task. Update laws were also designed to estimate the unknown dimensional parameters. To implement the designed controllers, a control system integrated with PIC16F877 microprocessors and a TMS320C32 DSP was developed. Simulation and experimental results are presented to show the effectiveness of the proposed controllers.

• 한국해양공학회:학술대회논문집
• /
• 한국해양공학회 2002년도 춘계학술대회 논문집
• /
• pp.209-214
• /
• 2002

We developed a small, remote controlled observation ship that can reduce the cost of gathering data for marine and coastal environments. The control system is composed of three microprocessors, one is for overall mission control, another for control of propulsion motors, and the other for sensor operation. For communication system, we adopt direct and indirect methods based on the wireless modem of commercial cellular telephone. The former is a direct communication between the modems of the ship and the server, and the latter is an indirect communication via internet between the ship and the server. The performance of the ship is demonstrated with the results produced by sets of experiments.

• 전기학회논문지
• /
• 제58권7호
• /
• pp.1450-1455
• /
• 2009

Assumed that an IPTV camera system is to be used as an ad-hoc sensor for the surveillance and diagnostics of safety-critical equipments installed in the in-containment building of the nuclear power plant, an major problem is the presence of high dose-rate gamma irradiation fields inside the one. In order to uses an IPTV camera in such intense gamma radiation environment of the in-containment building, the radiation-weakened devices including a CCD imaging sensor, FPGA, ASIC and microprocessors are to be properly shielded from high dose-rate gamma radiation using the high-density material, lead or tungsten. But the passive elements such as mirror, lens and window, which are placed in the optical path of the CCD imaging sensor, are exposed to a high dose-rate gamma ray source directly. So, the gamma-ray irradiation characteristics of the passive elements, is needed to test. A CCD camera lens, made of glass material, have been gamma irradiated at the dose rate of 4.2 kGy/h during an hour up to a total dose of 4 kGy. The radiation induced color-center in the glass lens is observed. The degradation performance of the gamma irradiated lens is explained using an color component analysis.

• 한국정보통신학회논문지
• /
• 제10권8호
• /
• pp.1422-1427
• /
• 2006

임베디드 마이크로프로세서가 소프트웨어를 수행하면서 소비하는 전력을 예측하기 위해서는 마이크로프로세서의 각 명령어가 수행하면서 소비하는 전류를 측정하여 활용한다. 본 논문에서는 임베디드 마이크로프로세서 adc16s310의 산술 및 논리 명령어에 대한 소비 전류를 측정 및 분석하고, 이를 바탕으로 적은 수의 측정 소비 전류 값을 사용하여 비교적 정확하게 모든 명령어 수행의 소비 전류 값을 예측할 수 있는 전력 예측 모델을 제안한다. 본 예측 모델은 마이크로프로세서 adc16s310의 산술 및 논리 명령어에 대하여 총 측정 공간 중 약5.84%의 공간에 대한 측정 전류 값만을 사용하여 평균 오차 0.34%에서 소비 전류 값을 예측할 수 있다.

• 한국산학기술학회논문지
• /
• 제7권3호
• /
• pp.512-517
• /
• 2006

본 논문에서는 태양광 발전시스템의 최대전력추종을 위해 퍼지 이론을 도입한 퍼지제어기를 설계하였다. 퍼지제어기의 디지털 설계를 위해 태양광 발전시스템의 각 부분을 구성하고, FPGA를 사용하여 제어기를 구현하였다. 구현된 제어기는 일사량의 변화에도 안정적으로 동작하며, 출력전압의 리플이 작은 결과를 보였다. 또한 FPGA의 퍼지제어기로서의 구현가능성을 발견하고 그 타당성을 입증하였다.

• Journal of Astronomy and Space Sciences
• /
• 제11권1호
• /
• pp.41-52
• /
• 1994

Currently, the CCDs are widely used in astronomical observations either in direct imaging use or spectroscopic mode. However according to the recent technical advances, new large format CCDs are rapidly developed which have better performances with higher quantum efficiency and sensitivity. In many cases, some microprocessors have been adopted to deal with necessary digital logic for a CCD imaging system. This could often lack the flexibility of a system for a user for to upgrade with new devices, especially if it is a commercial product. A new design concept has been explored which could provide the opportunity to deal with any format of devices from any manufactures effectively for as tronomical purposes. Recently available PLD (Programmable Logic Devices)technology makes it possible to develop such digital circuit design, which can be integrated into a single component, instead of using micrprocessors. The design concept could dramatically increase the efficiency and flexibility of a CCD imaging system, particularly when new or large format devices are available and to upgrade the performance of a system. Some variable system control parameters can be selected by a user with a wider range of choice. The software can support such functional requirements very conveniently. This approach can be applied not only to astronomical purpose, but also to some related fields, such as remote sensing and industrial applications.

• 한국고분자학회:학술대회논문집
• /
• 한국고분자학회 2006년도 IUPAC International Symposium on Advanced Polymers for Emerging Technologies
• /
• pp.41-41
• /
• 2006

Step and Flash Imprint Lithography is an interesting low cost alternative to traditional microlithographic processes that offers the ability to efficiently produce nanostructures at unprecedented resolution. New photopolymerizable formulations are required to enable this process. This paper will describe progress in the design and development of acrylate and vinyl ether based platforms for this application together with efforts to prepare photopolymerizable, thermally stable, magterials with low dielectric constants for use in an efficient new method for fabricating the interconnect structures in microprocessors.

• 한국광학회지
• /
• 제12권3호
• /
• pp.200-204
• /
• 2001

1530-1560nm와 1 570-1600nm 대역에서 이득을 갖는 640Gbps(10 Gbps$\times$64채널) 파장 다중화된 광신호 증폭용 유니트를 설계, 제작하고 특성을 측정하였다. 640Gbps 광신호 즈옥 유니트의 이득 블록은 최적 광출력 특성을 유지하고 이득 불록의 동작 상태를 감시할 수 있도록 마이크로 프로세서에 의해서 제어된다. 640 Gbps 광신호 증폭 유니트의 각 대역별 광증폭 유니트는 총 입력 광 세기 범위 -5~+1 dBm에서 이득 평탄도 1dB이내 잡음 지수 7.2dB 이내 +21dBm 이상의 고출력 특성을 갖는다.