• Title/Summary/Keyword: scaling function

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A Performance Variation by Scaling Factor in NM-MMA Adaptive Equalization Algorithm (NM-MMA 적응 등화 알고리즘에서 Scaling Factor에 의한 성능 변화)

  • Lim, Seung-Gag
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.18 no.2
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    • pp.105-110
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    • 2018
  • This paper compare the adaptive equalization performance of NM-MMA (Novel Mixed-MMA) algorithm which using the mixed const function by scaling factor values. The mixed cost function of NM-MMA composed of the appropriate weighted addition of gradient vector in the MMA and SE-MMA cost function, and updating the tap coefficient based on these function, it is possible to improve the convergence speed and MSE value of current algorithm. The computer simulation was performed in the same channel, step size, SNR environment by changing the scaling factor, and its performance were compared appling the equalizer output constellation, residual isi, MD, MSE, SER. As a result of computer simulation, the residual values of performance index were reduced in case of the scaling factor of MMA cost function was greater than the scaling factor of SE-MMA. and the convergence speed was improved in case of the scaling factor of SE-MMA was greater than the MMA.

SCALING FUNCTIONS SUPPORTED IN INTERVALS OF LENGTH $\leq$3

  • Lee, Jung-Seob
    • Communications of the Korean Mathematical Society
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    • v.9 no.4
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    • pp.891-896
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    • 1994
  • Daubechies [1] discoverd compactly supported scaling functions and corresponding wavelets with high regularities. It seems that there are no known compactly supported scaling functions other than Daubechies'. In this article, we will construct new scaling functions supproted in intervals of length $\leq 3$ without using deep analysis. While one of them is Daubechies' scaling function, others are less regular than Daubechies'. Also, we will show that Daubechies' scaling function is the unique one with highest regularity.

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A new Robust Wavelet Shift Keying System Using Scaling and Wavelet Functions (스케일링 함수와 웨이브릿을 이용한 잡음에 강인한 새로운 웨이브릿 편이 변조 시스템)

  • Jeong, Tae-Il
    • Journal of the Institute of Convergence Signal Processing
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    • v.9 no.2
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    • pp.98-103
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    • 2008
  • There are the frequency shift keying(FSK), phase shift keying(PSK) and amplitude shift keying(ASK) in the conventional digital communications method. In this paper, We proposed a new robust wavelet shift keying system using scaling and wavelet function in the digital communication. Wavelet Transform consist of a low frequency and high frequency coefficient. When the input signal is one, if it finds the impulse response, the signal is separated from the scaling and wavelet function. The binary data is encoded by modulator which assigned the scaling function to 1(one), and wavelet to zero(0). It was demonstrated by experiment that the proposed algorithm can be a robust noise.

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ORTHOGONAL TWO-DIRECTION REFINABLE FUNCTION OF ORDER 3

  • KWON, SOON-GEOL
    • Journal of applied mathematics & informatics
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    • v.37 no.3_4
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    • pp.307-315
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    • 2019
  • In this paper we construct orthogonal two-direction scaling function of order 3 and corresponding wavelet function. In this paper we propose a different approach using orthogonal symmetric/antisymmetric multiwavelets of order 3. An example for constructing orthogonal two-direction scaling function of order 3 and corresponding wavelet function is given.

The Structure of Scaling-Wavelet Neural Network (스케일링-웨이블렛 신경회로망 구조)

  • 김성주;서재용;김용택;조현찬;전홍태
    • Proceedings of the Korean Institute of Intelligent Systems Conference
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    • 2001.05a
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    • pp.65-68
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    • 2001
  • RBFN has some problem that because the basis function isnt orthogonal to each others the number of used basis function goes to big. In this reason, the Wavelet Neural Network which uses the orthogonal basis function in the hidden node appears. In this paper, we propose the composition method of the actual function in hidden layer with the scaling function which can represent the region by which the several wavelet can be represented. In this method, we can decrease the size of the network with the pure several wavelet function. In addition to, when we determine the parameters of the scaling function we can process rough approximation and then the network becomes more stable. The other wavelets can be determined by the global solutions which is suitable for the suggested problem using the genetic algorithm and also, we use the back-propagation algorithm in the learning of the weights. In this step, we approximate the target function with fine tuning level. The complex neural network suggested in this paper is a new structure and important simultaneously in the point of handling the determination problem in the wavelet initialization.

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A LOGARITHMIC CONJUGATE GRADIENT METHOD INVARIANT TO NONLINEAR SCALING

  • Moghrabi, I.A.
    • Journal of the Korean Society for Industrial and Applied Mathematics
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    • v.8 no.2
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    • pp.15-21
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    • 2004
  • A Conjugate Gradiant (CG) method is proposed for unconstained optimization which is invariant to a nonlinear scaling of a strictly convex quadratic function. The technique has the same properties as the classical CG-method when applied to a quadratic function. The algorithm derived here is based on a logarithmic model and is compared to the standard CG method of Fletcher and Reeves [3]. Numerical results are encouraging and indicate that nonlinear scaling is promising and deserves further investigation.

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Analysis of the Effects of Scaling Factors of Fuzzy Controller (퍼지 제어기의 Scaling Factor의 영향 분석)

  • Lee, Chul-Heui;Seo, Seon-Hak
    • Journal of Industrial Technology
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    • v.15
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    • pp.195-202
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    • 1995
  • In this paper, we analyze the effects of scaling factors on the performance of a fuzzy controller. The quantitative relation between input and output variables of a fuzzy controller is obtained by using a quasi-linear fuzzy model. And an approximate transfer function of a fuzzy controller is derived from the comparison of fuzzy controller with the conventional PID controller. Then we analyze the effects of scaling factor using this approximate transfer function and root locus method.

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Comparative Study of Functional Magnetic Resonance Imaging by Global Scaling Analysis (Global Scaling 분석방법에 따른 기능적 자기공명영상의 비교 연구)

  • Yoo, Dong-Soo
    • Investigative Magnetic Resonance Imaging
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    • v.10 no.1
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    • pp.26-31
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    • 2006
  • Purpose : To evaluate the effect of global scaling analysis on brain activation for sensory and motor functional MR imaging study. Materials and methods : Four normal subjects without abnormal neurological history were included. Arm extension-flexion movement was used for motor function and 1KHz pure tone stimulation was used for auditory function. Functional magnetic resonance imaging was performed at 3T MRI (GE, Milwaukee, USA) using BOLD-EPI technique and SPM2 was employed for data analysis. On data analysis, the brain activation images were obtained with and without global scaling by fixing other parameters such as motion correction and realignment. Results : The difference in brain activation between no scaling and global scaling was not large in case of right upper extremity movement (p<0.000001). For auditory test, brain activation with global scaling showed larger activation than that of without global scaling (p<0.05). Conclusion : A caution must be taken into account when analyzing functional imaging data with global scaling especially for functional study of small local BOLD signal change.

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A Study on the Performance Analysis of 4-ary Scaling Wavelet Shift Keying (4-ary 스케일링 웨이브릿 편이 변조 시스템의 성능 분석에 관한 연구)

  • Jeong, Tae-Il;Ryu, Tae-Kyung;Kim, Jong-Nam;Moon, Kwang-Seok;Kim, Hyun-Deok
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.14 no.5
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    • pp.1155-1163
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    • 2010
  • An algorithm of the conventional wavelet shift keying is carried out that the scaling function and wavelet are encoded to 1(mark) and 0(space) for the input binary data, respectively. Two bit modulation technique which uses four carrier frequencies is existed. Four carrier frequencies are defined as scaling function, inversed scaling function, wavelet, and inversed wavelet, which are encoded to 10, 11, 00 and 01, respectively. In this paper, we defined 4-ary SWSK (4-ary scaling wavelet shift keying) which is two bit modulation, and it is derived to the probability of bit error and symbol error of the defined system from QPSK. In order to analyze to the performance of 4-ary SWSK, we are obtained in terms of the probability of bit error and symbol error for QPSK (quadrature phase shift keying), MFSK(M-ary frequency shift keying) and proposed method. As a results of simulation, we confirmed that the proposed method was superior to the performance in terms of the probability of bit error and symbol error.