• 한국측량학회:학술대회논문집
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• 한국측량학회 2009년도 춘계학술발표회 논문집
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• pp.11-13
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• 2009

본 연구는 최신의 수치지도 확보를 위한 갱신방안으로서 건축 및 다양한 SOC 건설공사에서 사용되고 있는 CAD 자료의 준공도면을 활용하여 수치지도를 갱신하기 위해 GIS 데이터로 변환하는 기법을 제시하였다. 변환과정은 레이어 추출, 객체변환, 좌표변환, 포맷변환으로 구성되며 CAD 데이터로부터 각 과정을 거쳐 변환된 GIS 데이터는 수치지도를 갱신할 수 있다.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2000년도 춘계학술대회논문집
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• pp.269-273
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• 2000

This paper describes Active Noise Control (ANC) using Discrete Wavelet Transform (DWT) Domain Least Mean Square (LMS) Method. DWT-LMS is one of the transform domain input decorrelation LMS and improves the convergence speed of adaptive filter especially when the input signal is highly correlated. Conventional transform domain LMS's use Discrete Cosine Transform (DCT) because it offers linear band signal decomposition and fast transform algorithm. Wavelet transform can project the input signal into the several octave band subspace and offers more efficient sliding fast transform algorithm. In this paper, we propose Wavelet transform domain LMS algorithm and shows its performance is similar to DCT LMS in some cases using ANC simulation.

• Nuclear Engineering and Technology
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• 제39권3호
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• pp.221-230
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• 2007

Wavelet theory was applied to detect a singularity in a reactor power signal. Compared to Fourier transform, wavelet transform has localization properties in space and frequency. Therefore, using wavelet transform after de-noising, singular points can easily be found. To test this theory, reactor power signals were generated using the HANARO(a Korean multi-purpose research reactor) dynamics model consisting of 39 nonlinear differential equations contaminated with Gaussian noise. Wavelet transform decomposition and de-noising procedures were applied to these signals. It was possible to detect singular events such as a sudden reactivity change and abrupt intrinsic property changes. Thus, this method could be profitably utilized in a real-time system for automatic event recognition(e.g., reactor condition monitoring).

• 전자공학회논문지
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• 제51권9호
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• pp.30-40
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• 2014

본 논문에서는 Hadamard 변환이 Jacket 변환으로 일반화 될 수 있는 것처럼 Haar 변환을 Jacket-Haar 변환으로 일반화 한다. Jacket-Haar 변환의 원소는 0 과 ${\pm}2^k$ 이다. original Haar 변환과 비교해서 Jacket-Haar 변환의 베이시스(basis)는 신호처리에 보다 적합하다. 응용으로 $2{\times}2$ Hadamard 행렬을 기반으로 한 DCT-II(discrete cosine transform-II)와 $2{\times}2$ Haar 행렬을 기반으로 한 HWT(Haar Wavelete transform)를 제시하고 이들의 성능을 분석하며 Lenna 이미지의 시뮬레이션을 통해 성능을 평가하였다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2000년도 하계학술대회 논문집 C
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• pp.1918-1920
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• 2000

In this paper, acoustic signals in GIS were analyzed by using wavelet transform and FFT to distinguish sound source caused by collision of particles and partial discharges. As a result, the analysis using wavelet transform was more accurate than that using FFT. Therefore, wavelet transform was useful technique to analyze the acoustic signals in GIS.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1999년도 하계학술대회 논문집 B
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• pp.1017-1019
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• 1999

In this paper we present 2-dimensional image recovery method using Hadamard transform. Generally, the methods of Hadamard transform are more useful tools and much simplier than those of Fourier transform. The Hadamard transform can improve estimates when the detector is the source of noise. We take into account nonidealities in the system for the further improved image We also present the average mean square error(AMSE) associated with estimates with the results from computer simulations.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2000년도 ITC-CSCC -1
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• pp.482-485
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• 2000

A modified watershed transform is proposed which is context-free marker-controlled and minima imposition-free to reduce the over-segmentation and to speedup the transform. In contrast to the conventional methods in which a priori knowledge, such as flat zones, zones of homogeneous texture, and morphological distance, is required for marker extraction, context-free marker extraction is proposed by using the attention operator based on the GST (generalized symmetry transform). By using the context-free marker, the proposed watershed transform exploit marker-constrained labeling to speedup the computation and to reduce the over-segmentation by eliminating the unnecessary geodesic reconstruction such as the minima imposition and thereby eliminating the necessity of the post-processing of region merging. The simulation results show that the proposed method can extract context-free markers inside the objects from the complex background that includes multiple objects and efficiently reduces over-segmentation and computation time.

• International Journal of Fuzzy Logic and Intelligent Systems
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• 제1권1호
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• pp.24-28
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• 2001

Wavelet transforms are used for implementing digital watermarking methods in the frequency domain. In this paper, we construct the digital watermarking using various wavelet transforms such as the Daubechies transform, Coiflets transform, Symlets transform and the biorthogonal transform, and we compare each digital watermarking method with the others. We investigate the preservation of the watermark after the data compression attack based on the discrete on the discrete cosine transform. We show that the biorthogonal wavelet, denoted by bior3.5, has the best performance among the wavelet types we selected in an experiment.

• 대한전자공학회논문지TC
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• 제44권1호
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• pp.132-137
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• 2007

재킷 변환은 단순한 계산과 용이한 역변환, 그리고 크기 유연성을 갖는 변환의 일종이다. 재킷 변환은 잘 알려진 월쉬-아다마르 변환(WHT)과 중앙 하중 아다마르 변환(CWHT)의 일반화로서 이전 연구에서 보고한 바 있다. 본 논문에서는 WHT 또는 CWHT에서 유도되지 않는 새로운 부류의 재킷 변환을 제시한다. 이러한 부류의 변환은 임의의 우수 길이를 갖는 벡터에 대해 적용할 수 있고, 유한체에 대해 응용할 수 있으며, 오류 정정 부호의 구성에서도 유용하다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2015년도 제46회 하계학술대회
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• pp.87-88
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• 2015

본 논문에서는 제주풍력단지에 대한 측정 데이터(measured wind power outputs)를 기반으로 Fast Fourier Transform(FFT)을 실시하고, 이를 이용하여 각 풍력발전단지의 주파수 특성에 대해 분석해보고자 한다.