• Journal of applied mathematics & informatics
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• 제19권1_2호
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• pp.191-201
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• 2005

In this paper, the existence of periodic positive solution and the attractivity are investigated for the rational recursive sequence $x_{n+1} = (A + ax_{n_k})/(b + x{n-l})$, where A, a and b are real numbers, k and l are nonnegative integer numbers.

• Journal of Mechanical Science and Technology
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• 제17권3호
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• pp.409-421
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• 2003

The hierarchical recursive local-correlation PIV algorithm with CBC (correlation based correction) method was employed to increase the spatial resolution of PIV results and to reduce error vectors. The performance of this new PIV algorithm was tested using synthetic images, PIV standard images of Visualization Society of Japan, real flows including ventilation flow inside a vehicle passenger compartment and wake behind a circular cylinder with riblet surface. As a result, most spurious vectors were suppressed by employing the CBC method, the hierarchical recursive correlation algorithm improved the sub-pixel accuracy of PIV results by decreasing the interrogation window size and Increased spatial resolution significantly. However, with recursively decreasing of interrogation window size, the SNR (signal-to-noise ratio) in the correlation plane was decreased and number of spurious vectors was increased. Therefore, compromised determination of optimal interrogation window size is required for given flow images, the performance of recursive algorithm is also discussed from a viewpoint of recovery ratio and error ratio in the paper.

• The Journal of the Acoustical Society of Korea
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• 제22권3E호
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• pp.93-100
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• 2003

We present a recursive total least squares (RTLS) algorithm for adaptive system identification. So far, recursive least squares (RLS) has been successfully applied in solving adaptive system identification problem. But, when input data contain additive noise, the results from RLS could be biased. Such biased results can be avoided by using the recursive total least squares (RTLS) algorithm. The RTLS algorithm described in this paper gives better performance than RLS algorithm over a wide range of SNRs and involves approximately the same computational complexity of O(N²).

• 한국가시화정보학회:학술대회논문집
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• 한국가시화정보학회 2001년도 Proceedings of 2001 Korea-Japan Joint Seminar on Particle Image Velocimetry
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• pp.75-85
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• 2001

The hierarchic recursive local-correlation PIV algorithm with CBC(correlation based correction) method was developed to increase the spatial resolution of PIV results and to reduce error vectors. This new algorithm was applied to the single-frame and double-frame cross-correlation PIV techniques. In order to evaluate its performance, the recursive algorithm was tested using synthetic images, PIV standard images from Visualization Society of Japan, real flows including ventilation flow inside a vehicle passenger compartment and wake behind a circular cylinder with rib let surface. As a result, most spurious vectors were suppressed by employing CBC method. In addition, the hierarchical recursive correlation algorithm improved largely the sub-pixel accuracy of PIV results by decreasing the interrogation window size, increasing spatial resolution significantly.

• 한국통신학회논문지
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• 제25권10B호
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• pp.1785-1792
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• 2000

In this paper multi-rate non-recursive architecture for CIC(Cascaded Integrator-Comb) decimation filters with an arbitrary factor is proposed. The CIC filters are widely used in high speed wireless communication systems since they have multiplier-less and multi-rate low-power structure. Even conventional non-recursive CIC structure is multi-rate this architecture can be structured only in case of M-th power-of-two decimation factor. This paper proposes that muli-rate non-recursive CIC architecture can be structured with an any decimation factor of product form. Power consumption of the proposed architecture is compared with that of the conventional non-recursion architecture.

• 제어로봇시스템학회논문지
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• 제7권12호
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• pp.1031-1035
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• 2001

In this paper, a robust recursive control approach for nonlinear system, which is based on Lyapunov stability, is proposed. The proposed method can apply to extended systems including cascaded systems and the stability is guaranteed in the sense of Lyapunov. The recursive design procedure so called “robust recursive control approach” is used to find a stabilizing robust controller and simultaneously estimate the uncertainty parameters. First, a nonlinear model with uncertainties whose bounds are unknown is derived. Then, unknown bounds of uncertainties are estimated. By using these estimates, the stabilizing robust controller is updated at each step. This approach is applied to the pitch autopilot design of a nonlinear missile system and simulation results indicate good performance.

• 한국기계기술학회지
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• 제13권3호
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• pp.73-79
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• 2011

In this study, an analytical realization of end-milling system was introduced using recursive parametric modeling analysis. Also, the numerical mode analysis of end-milling system with different conditions was performed systematically. In this regard, a recursive least square modelling algorithm and the natural mode for real part and imaginary one was discussed. This recursive approach (RLSM) can be adopted for on-line end-milling identification. After experimental practice of the end-milling, the end-milling force was obtained and it was used for the calculation of FRF (Frequency response function) and mode analysis. Also the FRF was analysed for the prediction of a end-milling system using recursive algorithm.

• 산업경영시스템학회지
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• 제12권19호
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• pp.31-37
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• 1989

본 논문은 비선형 회귀분석 모델(Nonlinear Regression Models)에서의 추산잔차(Recursive Residuals)를 정의하기 위한 것을 목적으로 한다. 선형 회귀분석 모델(Linear Regression Models)에서는 추산잔차가 우리가 측정할 수 없는 진짜 오차(True Error)와 같은 확률 분포를 갖는데 이의 평균은 0이고 분산은 ${sigma}^2$이다. 그러나 비선형 회귀분석에서는 이와 같은 정확한 분포를 알 수가 없기 때문에, 여러 종류의 잔차들을 연구 검토하고 나아가서 시뮬레이션(Simulation)을 통하여 분석.비교한 뒤 추산잔차를 정의하기로 한다.

• Journal of Electrical Engineering and information Science
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• 제1권1호
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• pp.91-97
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• 1996

This paper proves by straightforward computation an interesting property of a recursive indexing: it preserves the entropy of a geometrically-distributes stationary memoryless source. This result is a pleasant surprise because the recursive indexing though one-to-one, is a symbol-to-string mapping and the entropy is measured in terms of the source symbols. This preservation of the entropy implies that the minimum average number of bits needed to represent a geometric memoryless source by the recursive indexing followed by a good binary encoder of a finite imput alphabet remains the same as that by a good encoder of an infinite input alphabet. Therefore, the recursive indexing theoretically keeps coding optimality intact. For this reason recursive indexing can provide an interface for a binary code with a finite code book that performs reasonably well for a source with an infinite alphabet.

• 한국정보과학회논문지:소프트웨어및응용
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• 제26권12호
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• pp.1542-1552
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• 1999

자료 병렬성이란 자료 집합의 원소들에 대하여 동일한 작업을 동시에 수행하므로써 얻어지는 병렬성을 말한다. 함수형 언어에서 자료 집합에 대한 반복 수행은 재귀적 자료형에 대한 재귀 함수에 의하여 표현된다. 본 논문에서는 이러한 재귀 함수를 자료 병렬 프로그램으로 변환하기 위한 병렬화 방법을 제시한다. 생성되는 병렬 프로그램의 병렬 수행 구조로는 일반적인 형태의 재귀적 자료형에 대하여 정의되는 다형적인 자료 병렬 연산을 사용하여 트리, 리스트 등과 같은 일반적인 재귀적 자료 집합에 대한 자료 병렬 수행이 가능하도록 하였다. 재귀 함수의 병렬화를 위해서는, 함수를 이루는 각각의 계산들의 병렬성을 재귀 호출에 의해 존재하는 의존성에 기반하여 분류하고, 이에 기반하여 각각의 계산들에 대한 적절한 자료 병렬 연산을 사용하는 병렬 프로그램을 생성하였다.Abstract Data parallelism is obtained by applying the same operations to each element of a data collection. In functional languages, iterative computations on data collections are expressed by recursions on recursive data structures. We propose a parallelization method for data-parallel implementation of such recursive functions. We employ polytypic data-parallel primitives to represent the parallel execution structure of the object programs, which enables data parallel execution with general recursive data structures, such as trees and lists. To transform sequential programs to their parallelized versions, we propose a method to classify the types of parallelism in subexpressions, based on the dependencies of the recursive calls, and generate the data-parallel programs using data-parallel primitives appropriately.