• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2001.11b
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• pp.1394-1399
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• 2001

The purpose of this paper is that investigates the dynamic behavior characteristic of W.T.S(Wind Turbine System) and carries out the evaluation analysis during operating W.T.S. To investigate the dynamic behavior characteristic of W.T.S. the experiments to measure vibration of the blade from the attached accelerometer on the flap and edge section of the blade that is one of the most important elements of dynamic characteristic of W.T.S are performed. Natural frequency and mode shape are calculated with commercial program (STAR MODAL) using the measured vibration acceleration that receives the signal with F.F.T Analyzer from the accelerometer. For validation of these experiments. the finite element analysis is performed with commercial F.E.M Program (ANSYS) on the basis of the natural frequency and mode shape. The results indicate that experimental values have good agreements with the finite element analysis.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2005.11a
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• pp.98-102
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• 2005

Most bearing casings are designed to focus on strength and weight of themselves because rotor speed passes through the critical speed when operation begins in large plants such as power plants. And It is treated importantly the relation between rotating frequency of the rotor and the natural frequency of casings to prevent resonance. But there is some cases that it is overlooked for harmonic components above rotating frequency. So we present experimentally a case that harmonic forces may make a resonance on casing fixing probes to measure vibration in a turbine-generator system and the vibration is generated when one component of harmonic forces excites the mode that the natural frequency of a certain bearing casing is close to one of harmonics of basic rotating frequency (1x).

• Fisheries and Aquatic Sciences
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• v.27 no.9
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• pp.552-564
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• 2024

This paper used the UK Agency for International Development sustainable livelihood framework to measure small-scale in-land fishing household's livelihood by sustainable livelihood capital index in the vulnerable context of aquatic natural resource depletion in the wetland forest of Ca Mau province, Vietnam. Findings indicated that fishing households' livelihood capital is unsustainable and inadequate. The result took note of the beneficial physical capital while underlining the human, natural, financial, and social capital's limitations in achieving livelihood sustainability. The limitations were found to be a low score of composite index of sustainable livelihood capital (less than an average score of 0.5) whereas the outstanding score of physical capital was found. Providing training in the adoption of new livelihood models, learning livelihood diversification, access to formal credit, and appropriate coverage of social safety-net programs might help mitigate the unsustainable livelihood of inland fishing households.

• Proceedings of the Korean Information Science Society Conference
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• 1999.10b
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• pp.315-317
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• 1999

미세한 차이를 고감도 식별하는 카오스 이론의 프랙탈 차원과 스트레인즈 어트랙터를 생성하는 수정된 에농 함수를 이용하여, 한글 2,350자에 대한 시계열 데이터의 혼도도를 분석하기 위해, 각각의 문자 0트랙터를 구성한 후, 프랙탈 차원을 나타내는 Box-counting Dimension 및 Natural Measure, Information Bit, Information Dimension 등을 구하여 문자 특징을 추출하는 새로운 알고리즘을 제시하였다. 실험결과 한글 2,350자에 대하여 99.23%의 분류율을 나타내어 제안된 방법의 유효성을 보였다.

• The Korean Journal of Applied Statistics
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• v.4 no.2
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• pp.129-135
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• 1991

A few simple methods to find $L_1$-unbiased estimators for location and scale parameters are summarized and examples utilizing diffusivity, a natural measure of dispersion for $L_1$-unbiased estimators, are given.

• International Journal of Fuzzy Logic and Intelligent Systems
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• v.15 no.2
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• pp.121-125
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• 2015

In this paper, we propose a method that extracts features from character patterns using the fractal dimension of chaos theory. The input character pattern image is converted into time-series data. Then, using the modified Henon system suggested in this paper, it determines the last features of the character pattern image after calculating the box-counting dimension, natural measure, information bit, and information (fractal) dimension. Finally, character pattern recognition is performed by statistically finding each information bit that shows the minimum difference compared with a normalized character pattern database.

• Journal of applied mathematics & informatics
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• v.8 no.1
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• pp.231-242
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• 2001

We showed in [2] that if r≤2, zero mean Gaussian of average error of the Trapezoidal rule is proportional to h/sub i//sup 2r+3/ on the interval [0,1]. In this paper, if r≥3, we show that zero mean Gaussian of average error of the Trapezoidal rule is bounded by Ch⁴/sub i/h⁴/sub j/.

• Proceedings of the Korea Water Resources Association Conference
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• 2009.05a
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• pp.2200-2204
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• 2009

In this paper the analysis of natural cause of Beijing Storm inundation and the effect of the human activities has been taken. Flood risk can hardly be eliminated solely by projects. Pre-warning system established is an efficient measure to minimize the influence of flood. Several main functions of this system and their examples are described in the paper, such as: monitoring, forecast, scheme, warning, dynamic decision-making and information publication.

• The Pure and Applied Mathematics
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• v.17 no.2
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• pp.175-183
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• 2010

Using Darbo's fixed point theorem, we establish the existence of monotone solutions for a nonlinear quadratic integral equation of Volterra type in the Banach space of real functions defined and continuous on a bounded and closed interval.

• Journal of the Korean Mathematical Society
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• v.32 no.4
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• pp.697-712
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• 1995

In the present article we consider multiparameter maximal averages and discover the crucial roles played by the number of parameters in their boundedness properties. The problem we shall deal with is initiated by Rubio de Francia [8] and will be in the spirit of an inductive extension to multiparameter cases, in which tools of our study rely on the theory of Harmonic Analysis on product spaces. Suppose that $d_\mu$ is a complex Borel measure supported on a compact subset S of $R^N$ having total mass one, $\smallint_S d_\mu = 1$.