• 전자공학회논문지B
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• 제31B권5호
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• pp.12-25
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• 1994

A two dimensional constant geometry FFT algorithms and architectures with shuffled inputs and normally ordered outputs are presented. It is suitable for VLSI implementation because all buterfly stages have identical, regular structure. Also a methodology using shuffled FFT inputs and outputs to halve the number of butterfly stages connected by a global interconnection which requires much area is presented. These algorithms can be obtained by shuffling the row and column of a decomposed FFT matrix which corresponds to one butterfly stage. Using non-recursive and recursive pipeline, the degree of serialism and parallelism in FFT computation can be adjusted. To implement high performance high radix FFT easily and reduce the amount of interconnections between stages, the method to build a high radix PE with lower radix PE 's is discussed. Finally the performances of the present architectures are evaluated and compared.

• 전자공학회논문지A
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• 제33A권7호
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• pp.23-33
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• 1996

This paper deals with the design of a recursively-indexed binary code for facsimile soruces and its performance. Sources used here are run-lengths of white pixels form higher-resolution facsimile. The modified huffman code used for G.3 facsimile is chosen for the performance comparison. Experiments confirm the fact that recursive indexing preserves the entropy of a memoryless geometric source: the entropy of recursively-indexed physical surce iwth roughly geometric distributin remains within 2% of the empirical source entropy. The designed recursively-indexed binary codes consist of a code applied to text-type documents and to graphics - type documents is compared iwth that of the modified huffman code. Numerical resutls show that the modified huffman code performs well for text-type documents and not equally well for graphics-tyep documents. On the other hand, recursively-indexed binary codes have shown a better performance for graphics-type documents whose distribution are similar to a geometric distribution. Specifically, the code rates of recursively-indexed binary codes with 60 codewords are from 8% to 20% of the empirical source entropy smaller than that of th emodified huffman code with 91 codewords.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2001년도 춘계학술대회 논문집
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• pp.971-974
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• 2001

In this study, the static and dynamic characteristics of endmilling process was modelled and the analytic realization of chatter mechanism was discussed. In this regard, We have discussed on the comparative assessment of recursive time series modeling algorithms that can represent the machining process and detect the abnormal machining behaviors in precision endmilling operation. In this study, simulation and experimental work were performed to show the malfunctional behaviors. For this purpose, new recursive(RLSM) were adopted for the on-line system identification and monitoring of a machining process, we can apply these new algorithms in real process for detection of abnormal chatter. Also, the stability lobe of chatter was analysed by varying parameter of cutting dynamices in regenerative chatter mechanics.

• 음성과학
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• 제8권2호
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• pp.73-81
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• 2001

In this paper, we focus on the real time implementation of the single channel adaptive noise canceller(ANC) by using TMS320C30 EVM board. The implemented single channel adaptive noise canceller is based on a reference paper [1] in which it is simulated by using the recursive average magnitude difference function(AMDF) to get a properly delayed input speech on a sample basis as a reference signal and normalized least mean square(NLMS) algorithm. To certify results of the real time implementation, we measured the processing time of the ANC and enhancement ratio according to various signalto-noise ratios(SNRs). Experimental results demonstrate that the processing time of the speech signal of 32ms length with delay estimation of every 10 samples is about 26.3 ms, and almost the same performance as given in [1] is obtained with the implemented system.

• 대한전기학회논문지:시스템및제어부문D
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• 제51권8호
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• pp.368-373
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• 2002

The inverse z-transform of a z-domain expression of a sequence can be Performed in many different methods among which the recursive computational method is based on the difference equation. In applying this method, a few initial values of the sequence should be obtained separately. Although the existing method generates the right initial values of the sequence, its derivation and justification are not theoretically in view of the definition of z-transform and its shift theorems. In this paper a general approach for formulating a difference equation and for obtaining required initial values of a sequence is proposed, which completely complies to the definition of the z-transform and an interpretation of the validity of the existing method which is theoretically incorrect.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 하계학술대회 논문집 A
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• pp.203-205
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• 2002

This paper presents the fault location estimation algorithm in transmission line using a recursive least square error method (RLSE). To minimize the computational burden of the digital relay a RLSE approach is used. Computer simulation results of the RLSE algorithm seem promising, indicating that it should be considered for further testing and evaluation.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2004년도 하계학술대회 논문집 Vol.5 No.2
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• pp.1234-1238
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• 2004

A Controlled neural networks are proposed in order to measure nonlinear environments in adaptive and in realtime. The structure of it is similar to recurrent neural networks: a delayed output as the input and a delayed error between tile output of plant and neural networks as a bias input. In addition, we compute the desired value of hidden layer by an optimal method instead of transfering desired values by backpropagation and each weights are updated by RLS(Recursive Least Square). Consequently, this neural networks are not sensitive to initial weights and a learning rate, and have a faster convergence rate than conventional neural networks. This new neural networks is Error Estimated Neural Networks. We can estimate nonlinear models in realtime by the proposed networks and control nonlinear models. To show the performance of this one, we have various experiments. And this controller call prove effectively to be control in the environments of various systems.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 학술대회 논문집 정보 및 제어부문
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• pp.334-336
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• 2005

According as quality of life improves, pursuit of agreeable iife became realistic problem. Specially, noise had been appraised to element that infiuence in human life directly and indirectly Therefore, necessity of study about noise control is increased for better labor conditions and agreeable habitat. In this paper, implementation of active mufflers using recursive LMS algorithms is presented. Analyze exhaust pipe noise of a gasoline and Diesel car and use adaptation IIR filter algorithm that stability is solidified and controled exhaust pipe noise of a car. computer simulation is performed to show the effectiveness of a proposed algorithm.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1992년도 하계학술대회 논문집 A
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• pp.305-307
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• 1992

This paper presents a technique, which identifies both process noise covariance and sensor noise covariance by using innovation correlation test. A correlation test, which checks whether the square root Kalman filter is workingly optimal or not, is given. The system is stochastic autoregressive moving-average model with auxiliary white noise Input. The linear quadratic Gaussian control is used for minimizing stochastic cost function. This paper indentifies Q, R, and estimates parametric matrics $A(q^{-1}),B(q^{-1}),C(q^{-1})$ by means of extended recursive least squares and model reference control. And The proposed technique has been validated in simulation results on the fourth order system.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2008년도 하계종합학술대회
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• pp.279-280
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• 2008

In order to improve the performance and simplify the structure of the conventional detectors in high density magnetic channels, a new equalizer based on bilinear recursive polynomial (BRP) models, which uses the previously estimated sequence, is proposed. The performance is compared with the conventional equalizers and the maximum likelihood sequence detection (MLSD) bound.