• Journal of information and communication convergence engineering
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• 제7권2호
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• pp.219-222
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• 2009

An efficient interpolation FIR filter structure for high-density and low-power electronic devices is proposed. The proposed structure is based on polyphase decomposition property and look-up table method. By computer-aided design simulations, it is shown that the use of the proposed method can result in reduction in the number of gates by 54% and can reduce power consumption by 9%.

• Bulletin of the Korean Chemical Society
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• 제14권2호
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• pp.238-243
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• 1993

A self-consistent-field Green's matrix method for the calculation of electronic properties of chemisorbed system is devised and applied to the methanol on copper(110) surface. The method is based on CNDO Hartree-Fock approximation. Contour integration in the complex energy plane is used for an efficient calculation of the charge-density bond-order matrix. The information on each fragment prior to chemisorption is efficiently used and a small number of iterations are needed to reach the self-consistency. The changes of density of states and other quantities of methanol due to chemisorption are consistent with reported experimental results.

• Journal of Information Processing Systems
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• 제16권4호
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• pp.750-759
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• 2020

The wide application of various integrated location-based services (LBS social) and tourism application (app) has generated a large amount of trajectory space data. The trajectory data are used to identify popular tourist attractions with high density of tourists, and they are of great significance to smart service and emergency management of scenic spots. A hot spot analysis method is proposed, based on spatial clustering of trajectory stop points. The DBSCAN algorithm is studied with fast clustering speed, noise processing and clustering of arbitrary shapes in space. The shortage of parameters is manually selected, and an improved method is proposed to adaptively determine parameters based on statistical distribution characteristics of data. DBSCAN clustering analysis and contrast experiments are carried out for three different datasets of artificial synthetic two-dimensional dataset, four-dimensional Iris real dataset and scenic track retention point. The experiment results show that the method can automatically generate reasonable clustering division, and it is superior to traditional algorithms such as DBSCAN and k-means. Finally, based on the spatial clustering results of the trajectory stay points, the Getis-Ord Gi* hotspot analysis and mapping are conducted in ArcGIS software. The hot spots of different tourist attractions are classified according to the analysis results, and the distribution of popular scenic spots is determined with the actual heat of the scenic spots.

• Journal of the Korean Data and Information Science Society
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• 제14권2호
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• pp.247-255
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• 2003

Hypothesis testing for the equality of two distributions were considered. Nonparametric kernel density estimates were used for testing equality of distributions. Cross-validatory choice of bandwidth was used in the kernel density estimation. Sampling distribution of considered test statistic were developed by resampling method, called the bootstrap. Small sample Monte Carlo simulation were conducted. Empirical power of considered tests were compared for variety distributions.

• Smart Structures and Systems
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• 제3권2호
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• pp.173-188
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• 2007

The general solution for two-dimensional magneto-electro-elastic media in terms of four harmonic displacement functions is proposed analytically. The expressions of specific solutions of magneto-electro-elastic plane problems with specific body forces are derived. Finally, based on the general solution in the case of distinct eigenvalues and the specific solution for density functionally gradient media, two kinds of beam problems with body forces depending only on the z or x coordinate are solved by the trial-and-error method.

• Journal of the Korean Wood Science and Technology
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• 제18권1호
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• pp.24-30
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• 1990

This study was attempted to propose a method evaluating fixation of active ingredients in Copper-Chromium-Arsenic preservatives treatment. Fixated amount of active ingredients on wood was obtained by measuring the density of surface electric charge based on $\varsigma$ potential. Data accumulated from density of surface electric charge showed that the fixated amount of preservatives on wood increased linearly as concentration of treating solution increaced, which indicatied quantitative reactions in fixation of preservatives.

• 한국인쇄학회지
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• 제10권1호
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• pp.15-22
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• 1992

This paper proposed correction tone density eq. and dot area eq. for perdict tone reproduction when dot gain is constant, and these are based on Yule & Nielson`s tone density equation. The experimental results show that proposed coreaction tone density eq. and dot area eq. are useful and valid for perdict tone reproduction of a half-tone image.

• International Journal of Computer Science & Network Security
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• 제22권11호
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• pp.308-318
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• 2022

Noise is a serious issue. While sending images via electronic communication, Impulse noise, which is created by unsteady voltage, is one of the most common noises in digital communication. During the acquisition process, pictures were collected. It is possible to obtain accurate diagnosis images by removing these noises without affecting the edges and tiny features. The New Average High Noise Density Median Filter. (HNDMF) was proposed in this paper, and it operates in two steps for each pixel. Filter can decide whether the test pixels is degraded by SPN. In the first stage, a detector identifies corrupted pixels, in the second stage, an algorithm replaced by noise free processed pixel, the New average suggested Filter produced for this window. The paper examines the performance of Gaussian Filter (GF), Adaptive Median Filter (AMF), and PHDNF. In this paper the comparison of known image denoising is discussed and a new decision based weighted median filter used to remove impulse noise. Using Mean Square Error (MSE), Peak Signal to Noise Ratio (PSNR), and Structure Similarity Index Method (SSIM) metrics, the paper examines the performance of Gaussian Filter (GF), Adaptive Median Filter (AMF), and PHDNF. A detailed simulation process is performed to ensure the betterment of the presented model on the Mini-MIAS dataset. The obtained experimental values stated that the HNDMF model has reached to a better performance with the maximum picture quality. images affected by various amounts of pretend salt and paper noise, as well as speckle noise, are calculated and provided as experimental results. According to quality metrics, the HNDMF Method produces a superior result than the existing filter method. Accurately detect and replace salt and pepper noise pixel values with mean and median value in images. The proposed method is to improve the median filter with a significant change.

• 한국농공학회논문집
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• 제55권5호
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• pp.49-58
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• 2013

Appropriate random variables and probability density functions based on statistical analysis should be defined to execute reliability analysis. Most studies have focused on only normal distributions or assumed that the variables showing non-normal characteristics follow the normal distributions. In this study, the reliability problem with non-normal probability distribution was dealt with using the convolution method in the case that the integration domains of variables are limited to a finite range. The results were compared with the traditional method (linear transformation of normal distribution) and Monte Carlo simulation method to verify that the application was in good agreement with the characteristics of probability density functions with peak shapes. However it was observed that the reproducibility was slightly reduced down in the tail parts of density function.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1994년도 추계학술대회 논문집
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• pp.54-58
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• 1994

H$_2$ bake and GeH$_4$ clean are used as a in-situ pre-clean method in low temperature Si based epitaxial growth technology using rapid thermal processing chemical vapor deposition (RTPCVD). In this paper, the H$_2$ bake and GeH$_4$ clean processes are optimized for low surface defect density using Taguchi method. In H$_2$ bake process, the epitaxial growth temperature affects dominantly on the surface defect density, and the next affecting factors are H$_2$ bake temperature and rinse time in de-ionised water. In GeH$_4$ clean process, GeH$_4$ clean temperature affects most strongly on the surface defect density, and the minor factor is GeH$_4$flow rate. The optimum process conditions predicted fly Taguchi method agree well with tile experimental data in both in-situ clean processes.