• Journal of computational fluids engineering
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• v.18 no.2
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• pp.93-98
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• 2013

In this paper, we reported the verification of numerical simulation approach for sedimentation of the multi-size particles in a container. The comparison between experimentally measured values and numerically evaluated values on settle down process of fully mixed mixture is carried out. In an attempt to represent the natural particle size distribution, various diameters of single particles are simulated and the results are compared with the outcome of the multi-size computation. When the empirical formula for mean particle size estimation is adopted to define the sediment diameter, computation and comparison are conducted.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2008.11a
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• pp.435-436
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• 2008

• Proceedings of the Safety Management and Science Conference
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• 2007.11a
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• pp.319-322
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• 2007

This paper presents geometrical product specifications of acceptance and verification tests for coordinate measuring machines(CMM). These specifications include vocabulary, measuring size, rotary table with fourth axis, scanning measuring mode, multiple-stylus probing systems, measuring, and, estimation of errors in computing Gaussian associated features.

• 한국도로학회:학술대회논문집
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• 2010.09a
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• pp.217-220
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• 2010

• Korean Journal of Optics and Photonics
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• v.2 no.1
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• pp.1-6
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• 1991

This paper describes the theoretical analysis of a diffraction pattern analyzer for the characterization of microscale object fields and a method for obtaining size and size distribution from the measured diffraction pattern of the object fields. For the experimental verification, a typical optical Fourier transform system was set up and calibrated with 2 5$\mu \textrm m$ and 50$\mu \textrm m$ pinholes. The system responses to distilled water droplets, alcohol, glycerin and silicon oil were imaged with vidicon, and the image was processed to determine the size distribution of each liquid particle field. The energy distribution function which is defined as the total intensity of a circular ring in the diffraction pattern was used to determine the dominant particle size of each liquid particle field.

• Journal of the Korean Institute of Telematics and Electronics B
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• v.33B no.7
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• pp.107-115
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• 1996

The average distortio of the vector quantizer is calcualted using a probability function F of the input source for a given codebook. But, since the input source is unknown in geneal, using the sample vectors that is realized from a random vector having probability function F, a time-average opeation is employed so as to obtain an approximation of the average distortion. In this case the size of the smple set should be large so that the sample vectors represent true F reliably. The theoretical inspection about the approximation, however, is not perfomed rigorously. Thus one might use the time-average distortion without any verification of the approximation. In this paper, the convergence characteristics of the time-average distortions are theoretically investigated when the size of sample vectors or the size of codebook gets large. It has been revealed that if codebook size is large enough, then small sample set is enough to obtain the average distortion by approximatio of the calculated tiem-averaged distortion. Experimental results on synthetic data, which are supporting the analysis, are also provided and discussed.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.21 no.6
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• pp.1533-1545
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• 1996

In this paper, the design and implementation of echo canceller with new variable step size algorithm is discussed. The method used in the new algorithm is to periodically adopt the test function which helps an optimal coefficient tracking. This algorithm outperforms LMS and VS algorithms in convergence speed and steady state error. As the period of test function is decreased, the speed of convergence is improved, but the number of calculation is increased, then the trade off between these parameters must be considered. Simulation results show new algorithm outperforms LMS and VS algorithms in convergence rate. For the design of hardware, circuit is designed with VHDL, and synthesized with Act1 withc is a FPGA library of ActelTM in use of synovation of InterGraph$^{TM}$. Verification of the synthesized circuit is carried out with simulator DLAB. The circuit based on the algorithm which is suggested in this paper calculated 7 radix places of inary number. A simulation data for the verification is based on the data of algorithm simulation. When the same input data is applied to the both simulation, output results of circuit simulation had slight difference in compare with that of algorithm simulation. The number of used gate is about 5,500 and We have 5.53MHz in maximum frequency.y.

• Journal of the Korea Fashion and Costume Design Association
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• v.7 no.3
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• pp.27-37
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• 2005

This study is aimed at the ready-mades size system and satisfaction of consumers size for woman's wear at domestic market which are made by public production systems. This study, particularly, is focused on jacket of 20-30 aged woman's wear in twenties & thirties female clothe. The procedures of this study are as follows; 1. Select 25 domestic clothing companies that its product has targeted in twenties & thirties female and investigate the system of each pattern size 2. Select 259 female in twenties & thirties randomly in Seoul survey a standad of females jacket purchase. Analysis of this study is based on SPSS statistics program, technical statistics, $X^2$ and ANOVA verification. The results of studying are as follows; 1. The survey of pattern size of the domestic females clothing companies has shown some distinctive feature at age and body type of their consumers. 2. Crucial point of female consumers in twenties & thirties is a design and fitness of their jacket while they are purchasing their jacket. 3. Female consumers have some dissatisfaction for the variety of size, difficulty of purchasing and size of bust, shoulder & length of arms of their jacket.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.41 no.3
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• pp.175-182
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• 2004

There is a growing interest in speaker verification, which verifies someone by his/her voices. There are many speaker vitrification algorithms such as HMM and DTW. However, it is impossible to apply these algorithms to memory limited applications because of large number of feature vectors to register or verify users. In this paper we introduces a speaker verification system using SVM, which needs a little memory usage and computation time. Also we proposed hardware architecture for SVM. Experiments were conducted with Korean database which consists of four-digit strings. Although the error rate of SVM is slightly higher than that of HMM, SVM required much less computation time and small model size.

• Phonetics and Speech Sciences
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• v.1 no.4
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• pp.127-132
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• 2009

The feature vectors which are used in conventional speaker recognition (SR) systems may have many correlations between their neighbors. To improve the performance of the SR, many researchers adopted linear transformation method like principal component analysis (PCA). In general, the linear transformation of the feature vectors is based on concatenated form of the static features and their dynamic features. However, the linear transformation which based on both the static features and their dynamic features is more complex than that based on the static features alone due to the high order of the features. To overcome these problems, we propose an efficient method that applies linear transformation and temporal information of the features to reduce complexity and improve the performance in speaker verification (SV). The proposed method first performs a linear transformation by PCA coefficients. The delta parameters for temporal information are then obtained from the transformed features. The proposed method only requires 1/4 in the size of the covariance matrix compared with adding the static and their dynamic features for PCA coefficients. Also, the delta parameters are extracted from the linearly transformed features after the reduction of dimension in the static features. Compared with the PCA and conventional methods in terms of equal error rate (EER) in SV, the proposed method shows better performance while requiring less storage space and complexity.