• Title/Summary/Keyword: Walsh functions

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A Goodness-Of-Fit Test for Adaptive Fourier Model in Time Series Data

  • Lee, Hoonja
    • Communications for Statistical Applications and Methods
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    • v.10 no.3
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    • pp.955-969
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    • 2003
  • The classical Fourier analysis, which is the typical frequency domain approach, is used to detect periodic trends that are of the sinusoidal shape in time series data. In this article, using a sequence of periodic step functions, describes an adaptive Fourier series where the patterns may take general periodic shapes that include sinusoidal as a special case. The results, which extend both Fourier analysis and Walsh-Fourier analysis, are applies to investigate the shape of the periodic component. Through the real data, compare the goodness-of-fit of the model using two methods, the adaptive Fourier method which is proposed method in this paper and classical Fourier method.

Nonorthogonal Basis Functions to Signal Processing (Nonorthogonal 기본함수의 신호처리)

  • 안성렬;이문호
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.10 no.1
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    • pp.31-37
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    • 1985
  • An interesting area of application which makes use of the unique features of the walsh series is that on non-linear stochastic problems. In particular, some success has been obtained in improving the efficiency of signal detection for those transducers which are essentially non-linear in operation. The set of harmonically-related nonorthogonal triangle waves is shown to form a basis apanning the same function space representable by fourier(trigonometric) series. A method for generating nonorthogonal bases for signal representation is presented tailor-made basis function can be used for specific purposes. Fundamental proofs of the basis properties of the representation are examined along with examples illustrating the techniques and computer simulation.

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A Study of Real-Time SHE-PWM Pattern Using Ordered Orthogonal Function (직교함수를 이용한 실시간 SHE-PWM 패턴 형성에 관한 연구)

  • Kim, Dae-Ik;Lee, Sang-Tae;Joe, Jun-Ik;Chon, Byoung-Sil
    • Journal of the Korean Institute of Telematics and Electronics B
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    • v.33B no.1
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    • pp.195-200
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    • 1996
  • In this paper, to eliminate some selected harmonics, we implement PWM inverter which can be able to control in real-time. Using walsh function, which is one of the ordered orthogonal functions, we propose a new method to calculate firing angles, and implement logic circuits which can be calculate firing angles in real-time and be applicable to 1- and 3-phase circuits. Finally, using simulation circuits which accept the outputs obtained from the implemented logic circuits as the inputs, we confirmed the characteristics in steady state of the proposed method for PWM inverter.

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The Effects of Prompted Voiding Therapy on Urinary Incontinence Control of Elderly Patients (노인환자의 요실금 조절을 위한 자극배뇨 요법의 효과)

  • 이경자;김미경;송희영
    • Journal of Korean Academy of Nursing
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    • v.27 no.4
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    • pp.943-952
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    • 1997
  • This study was done to analyze the effects of prompted voiding therapy on urinary incontinence in elderly patients in an elderly care hospital. Specifically, this study looks to evaluate the effects of prompted voiding as an intervention for improving independent voiding and also identified the relationship of urinary continence to cognitive, emotional, and physical factors. The study was based on a pre-experimental design used to evaluate the effects of prompted voiding therapy on an experimental group without a control group. An experimental group of 143 patients was selected through convenience sampling from patients in an elderly care hospital. The data was collected from November 4 to December 14, 1996. Prompted voiding therapy is a behavioral therapy for managing incontinence and it is applied to patients who are cognitively impaired and dependent. In this study, the patients were asked at each designated time whether or not they had to urinate. If they answered yes, they were either given a bedpan or were assisted to the bathroom, and if the patient answered no, their diaper was checked to determine whether or not it was wet. The results were then recorded on the patients urinary voiding record. The urinary voiding score based on the model presented by Burton(1984), Burke and Walsh(1992), Chenitz, Stone & Salisbury(1991) was modified and used as a tool in this study. After forty six out of the total of 143 patients were selected for interviews through random sampling the levels of cognitive functions, mental depression and ADL(activities of dally life) within the given time frame were measured. In this study, the cognitive function was measured using the scale developed by Kabhn, Goldfarb, Pollack & Peck(1960), elderly mental depression, using the tool developed by Sheikh & Yesavage(1986), and the ADL(activities of dally living), through the Barthel Index. The data was analyzed through SPSS windows for descriptive statistics, repeated measured ANOVA and Pearson's correlation. According to the results of the study, the application of the prompted voiding therapy can improve the voiding pattern of patients. It was shown especially that incontinence could be controlled by the intervention developed according to the individual voiding pattern. In terms of the relationship between cognitive function, mental depression and ADL and the voiding function score, a close correlation was not found. It was shown that urinary incontinence can be improved through therapy even though patients have problems nth their cognitive, mental and physical functions.

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