• 한국정보처리학회논문지
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• 제4권7호
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• pp.1900-1906
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• 1997

본 논문에서는 FPGA에 회로를 설계할 때, 일괄검사가 가능한 BIST의 효율적인 BILBO(이하 EBILBO)를 설계한다. 제안된 일괄검사 알고리즘은 회로의 복잡도와 규모가 큰 회로에서 하나의 핀(pin)으로 정상속도에서 회로검사가 가능하다. BIST 설계에서, 필요한 검사패턴은 의사 랜덤패턴으로 생성하고, 출력은 다중 입력 쉬프트 레지스터에 의한 병렬 신호분석으로 검사하였다. 제안된 알고리즘은 VHDL로 동작적 기술하므로 검사패턴 생성과 응답분석 및 압축에 대한 모델을 용이하게 변경할 수 있다. FPGA상에 설계된 회로에서, 구현된 BIST의 EBILBO의 면적과 성능은 ISCAS89 벤치마크 회로를 통하여 평가하였다. 600 셀(cell) 이상의 회로에서 EBILBO 면적은 30% 이하로 감소하고, 검사패턴은 500K 정도로 신축성 있게 생성되고, 고장검출률의 범위는 88.3%에서 100%임을 확인하였다. 일괄검사의 BIST를 위한 EBILBO 동작은 정상모드와 병행하여 실시간으로 검사모드를 $s+n+(2^s/2^p-1)$시간 내에 동시에 수행할 수 있다.(CUT의 PI 수;n, 레지스터 수;s, p는 다항식의 차수). 제안된 알고리즘은 VHDL 코딩으로 설계와 검사가 병행될 수 있는 라이브러리로 구축되어 DFT에 광범위하게 응용되어질 수 있다.

• 대한전기학회논문지:시스템및제어부문D
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• 제54권1호
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• pp.48-55
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• 2005

Mobility of an indoor wheeled robot is affected by adhesion force that is related to various floor conditions. When the adhesion force between driving wheels and floor decreases suddenly, the robot begins slip. In order to overcome this slip problem, optimal slip velocity must be decided for stable movement of wheeled robot. First of all, this paper shows that conventional PI control can not be applied to a wheeled robot of the light weight. Secondly, proposed fuzzy logic is applied to the Takagi-Sugeno model for the configuration of fuzzy sets. For the design of Takagi-Sugeno model and fuzzy rule, proposed algorithm uses FCM(Fuzzy c-mean clustering method) algorithm. In additionally, this algorithm adjusts the driving torque for restraining re-slip. The proposed fuzzy logic controller(FLC) is pretty useful with prevention of the slip phenomena for the controller performance in the re-adhesion control strategy, These procedures are implemented using a Pioneer 2-DXE wheeled robot parameter.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2000년도 제13회 신호처리 합동 학술대회 논문집
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• pp.375-378
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• 2000

In this paper, we propose a novo] content-based image retrieval system using both Hidden Markov Model(HMM) and an improved chain code. The Gaussian Mixture Model(GMM) is applied to statistically model a color information of the image, and Deterministic Annealing EM(DAEM) algorithm is employed to estimate the parameters of GMM. This result is used to segment the given image. We use an improved chain code, which is invariant to rotation, translation and scale, to extract the feature vectors of the shape for each image in the database. These are stored together in the database with each HMM whose parameters (A, B, $\pi$) are estimated by Baum-Welch algorithm. With respect to feature vector obtained in the same way from the query image, a occurring probability of each image is computed by using the forward algorithm of HMM. We use these probabilities for the image retrieval and present the highest similarity images based on these probabilities.

• 대한의용생체공학회:학술대회논문집
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• 대한의용생체공학회 1997년도 춘계학술대회
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• pp.471-474
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• 1997

Several selective excitation pulses are used in MRI. Because of the nonlinearity of the Block equation, the pulse problem is nonlinear generally. Recently, Shinnar & Le Roux have proposed a direct solution of this problem. In this paper, we introduce the SLR algorithm and design pulses using SLR algorithm. This SLR pulse produces a specified slice profile. For example, we demonstrate the sinc function pulse with piece wise constant duration ${\Delta}t$. Further, we will design $\pi/2$ pulse and slice profile.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1999년도 추계학술대회 논문집 학회본부 B
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• pp.488-490
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• 1999

This paper describes the design of self-tuning speed controller for DC motor drive system using RLS(Recursive Least Squares) algorithm and Pole-Placement method. The model parameters, related to inertia and damping coefficient of motor, are estimated on-line by using RLS estimation algorithm. And a control signal is calculated by using pole placement method. Simulation and experimental results show that the proposed controller possesses excellent adaptation capability than a conventional PI/IP controller under parameter change.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2005년도 ICCAS
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• pp.575-579
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• 2005

In this paper, the development of an IMM(Injection Molding Machine) controller is discussed. Presently, the Mold Close and Open Control Method of a toggle-type IMM is open-loop control. Through the development, a PC based control system was built instead of an existing controller and a closed-loop control replaced the previous control method by using PC based PLC. To control the nonlinear system of toggle type clamping unit, a fuzzy PI control algorithm was selected and it was programmed by an IL(Instruction List) and a LD(Ladder Diagram) on a PC based PLC. The application of fuzzy algorithm as the control method was also considered to change a control object like a mold replacement or an additional apparatus. For the development of an IMM controller, PC based PLC of PCI card type, distributed I/O modules with CANopen and Industrial PC and HMI (Human Machine Interface) software were used.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2008년도 하계종합학술대회
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• pp.319-320
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• 2008

In this paper, we propose a new frequency offset estimation algorithm for DBO-CSS which is a standard for wireless personal area network (WPAN). In DBO-CSS, there can be several integer multiples of $2{\pi}$ in the phase rotation caused by the frequency offset because of the long time difference between the samples of differential relation and the high permissible frequency offset of the crystal oscillators between the transmitter and the receiver. In this paper, we propose an estimation algorithm by using the relationships of each sub-chirp signals to find the integer part without phase ambiguity.

• Journal of Advanced Marine Engineering and Technology
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• 제30권6호
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• pp.746-752
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• 2006

This paper presents a scheme for the parameter estimation and stabilization of unstable systems, such as inverted pendulum systems. First a stable feedback loop is constructed for an inverted pendulum system and then its parameters are estimated based on input-output data, a real-coded genetic algorithm(RCGA) and the model adjustment technique. Then, a PI-type LQ control scheme is designed based on the estimated model. The performance of the proposed algorithm is demonstrated through a set of simulation and experiment.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2003년도 추계학술대회 논문집
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• pp.104-108
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• 2003

This paper explained algorithm for a initial pole position estimation of a permanent magnet linear synchronous motor(PMLSM). Generally this motor is considered initial pole position with a position sensor such as incremental encoder for the precise initial pole position estimation and high performance. But this is based on the principle that the initial pole position is accomplished by the PI controller using the maximum values of a position error generated by the new proposed two reference frames and also by using a rated force for input. the proposed algorithm does not utilize the general methods such as impedance ratio, EMF and using the magnetic saturation. In other words, this can be applied without respect to variety of the motor structure because of insensitivity to the motor parameters. In conclusion, simulation results are presented to confirm performance of initial pole position estimation method.

• 동력기계공학회지
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• 제3권1호
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• pp.67-73
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• 1999

It is not easy to control the speed of AC motors accurately without modeling with some parameters for the controlled system. However, there are some application parts which do not require high speed responses strictly and the motor parameters can not to be identified simply. In this paper, a speed control method for a synchronous motor(S.M) with unknown parameters of the motor is investigated. The method is based on the current control algorithm. Speed controller and current controller are designed using PI control law. Some experiments are performed using DSP and power expert system to prove the validity of the proposed method. Throughout experimental results, the method is confirmed successfully. This method is expected to control the system with unknown parameters of the S.M efficiently.