• Proceedings of the KSME Conference
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• 2001.06d
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• pp.605-611
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• 2001

A numerical technique for simulating the aggregation of charged particles was presented with a Brownian dynamic simulation in the free molecular regime. The Langevin equation was used for tracking each particle making up an aggregate. A periodic boundary condition was used for calculation of the aggregation process in each cell with 500 primary particles of 16 nm in diameter. We considered the thermal force and the electrostatic force for the calculation of the particle motion. The morphological shape of aggregates was described in terms of the fractal dimension. The fractal dimension for the uncharged aggregate was $D_{f}=1.761$. The fractal dimension changed slightly for the various amounts of bipolar charge. However, in case of unipolar charge, the fractal dimension decreased from 1.641 to 1.537 with the increase of the average number of charges on the particles from 0.2 to 0.3 in initial states.

• Journal of the Korean Institute of Telematics and Electronics B
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• v.33B no.3
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• pp.169-175
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• 1996

In this paper, a new parallel neural network system that performs dynamic competitive learning is proposed. Conventional learning mehtods utilize the full dimension of the original input patterns. However, a particular attribute or dimension of the input patterns does not necessarily contribute to classification. The proposed system consists of parallel neural networks with the reduced input dimension in order to take advantage of the information in each dimension of the input patterns. Consensus schemes were developed to decide the netowrks performs a competitive learning that dynamically generates output neurons as learning proceeds. Each output neuron has it sown class threshold in the proposed dynamic competitive learning. Because the class threshold in the proposed dynamic learning phase, the proposed neural netowrk adapts properly to the input patterns distribution. Experimental results with remote sensing and speech data indicate the improved performance of the proposed method compared to the conventional learning methods.

• KSTLE International Journal
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• v.3 no.2
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• pp.75-78
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• 2002

The surface morphology of oil-lubricated surfaces fer hydraulic piston motors is believed to be extremely effective in contact mechanics, adhesion, friction and weak In order to describe morphology of various rubbed surfaces on driving conditions, the wear test was carried out under different experimental conditions in an oil-lubricated system. And fractal descriptors were applied to rubbed surfaces of hydraulic members and analyzed through an image processing system. These descriptors to analyze surface structure are fractal dimension. Surface fractal dimensions can be determined by sum of intensity difference of surface pixel. The morphology of rubbed surfaces can be effectively obtained by fractal dimension.

• The korean journal of orthodontics
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• v.14 no.2
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• pp.263-272
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• 1984

This study was undertaken to examine the extent to which tooth size and jaw size each contribute to dental crowding. Two groups of dental casts were selected on the basis of dental crowding. One group, consisting of 94 pairs of dental casts (46 males and 48 females) with normal occlusion. A second group, consisting of 84 pairs of dental casts (98 males and 46 females) with crowding. The results were as follows. 1. Means and standard deviations of the two groups were used to compare the two groups. 2. Significant differences were observed between two groups on the basis of tooth size, arch dimension and arch perimeter. 3. Between noncrowded group and crowded group, was crowded group was found to have large troth size than noncrowded group, while smaller arch dimension and perimeter. 4. Significant differences were observed between males and females on the basis of tooth size, arch dimension and arch perimeter. 5. Author found ideal arch shape of normal occlusion.

• Phonetics and Speech Sciences
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• v.7 no.4
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• pp.3-8
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• 2015

In this paper, we investigate an input dimension reduction method using continuous word vector in deep neural network language model. In the proposed method, continuous word vectors were generated by using Google's Word2Vec from a large training corpus to satisfy distributional hypothesis. 1-of-${\left|V\right|}$ coding discrete word vectors were replaced with their corresponding continuous word vectors. In our implementation, the input dimension was successfully reduced from 20,000 to 600 when a tri-gram language model is used with a vocabulary of 20,000 words. The total amount of time in training was reduced from 30 days to 14 days for Wall Street Journal training corpus (corpus length: 37M words).

• Transactions of Materials Processing
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• v.13 no.1
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• pp.3-8
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• 2004

The improvement of dimensional accuracy for forged part is one of major goals in cold forging industry. There are many problems in controlling the dimension by the trial-and-error, especially for a precision forged gear. A FEM analysis has been used in developing the forging technology. However, FE techniques have to be reconfirmed for predicting accurately the dimension of forged part. In this study, the effects of elastic characteristics and temperature changes are investigated by the comparisons between experimental and FEA in cold forging. When FE models related with elastic characteristics are considered practically, FE results could predict the part dimension within the range of $10\mu\textrm{m}$. And if thermal effects also are considered additionally, the predicted dimensions are well coincided with the experimental down to about $5\mu\textrm{m}$.

• Journal of the Korean housing association
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• v.14 no.5
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• pp.105-116
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• 2003

The purpose of this study is to suggest the method of prevention of staircase accidents, and to make housing environment better through researching the dimension of a housing staircase for Korean. The scope and method of this thesis is to investigate the dimension limits of a staircase (slope, minimum width of tread, maximum height of riser), and to analyze the characteristics of foot condition (jutting rate, foot angle, ball joint, nosing clearance, clearance distance) using the experiment which takes a photograph of foot motion during walking stairs. The results of this thesis are as follows. The slope of a staircase in house is $32.3^{\circ}$$^{\circ}$-$42.1^{\circ}$$^{\circ}$. The riser should be less than 190 mm. The minimum size of tread is 210 mm and proper size is 270 mm.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.15 no.3
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• pp.67-72
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• 2006

There are many modelling methods using theoretical and experimental data. Recently, fractal interpolation methods have been widely used to estimate and analyze various data. Due to the chaotic nature of dynamic roundness profile data in roundness some desirable method must be used for the analysis which is natural to time series data. Fractal analysis used in this paper is within the scope of the fractal interpolation and fractal dimension. Also, two methods for computing the fractal dimension has been introduced which can obtain the dimension of typical dynamic roundness profile data according to the number of data points in which the fixed data are generally lower than 200 data points. This fractal analysis result shows a possible prediction of roundness profile that has some different roundness profile in round shape operation.

• Journal of the Korean Society of Costume
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• v.54 no.4
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• pp.113-127
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• 2004

This study examined the trend of pattern which appeared throughout men's clothing fashion magazine from 1999 to 2002 and the influence which the demographic characteristic have on the sensibility dimension of pattern and the preference degree of kinds of pattern. The results of study were as follows. 1) The pattern which was used most frequently on recent men's clothing was a length stripe, and the representation technique which was used most frequently on recent men's clothing was the technique of a geometric expression. 2) The pattern which men and women preferred most out of ten kinds of patterns-length stripe, width stripe, oblique stripe, check, square, waterdrop, paisley, flower of style shape, flower of realistic shape, flower of shape-was a length stripe. 3) The sensibility dimension of pattern image was composed of fascination, dignity, daring, gentleness, and reality. 4) Because sensitivity dimension and kinds of pattern were significant according to the distinction of sex, vocation, academic career, income, this study can conclude the demographic characteristic have an influence on sensitivity dimension and kinds of pattern.

• Journal of Information Technology Applications and Management
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• v.9 no.2
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• pp.81-106
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• 2002

As more organizations undertake IT-enabled business process reengineering(BPR), IT-enabled BPR projects become a major concern. Especially, one of IT, Enterprise Resource Planning System (ERP) is recognized as a revolution solution. But the success cases of ERP project are rarely reported. In this study, ERP implementation is defined as a IS implementation project based on BPR concepts To explore the issues of implementing ERP systems, a company implementing ERP successfully in Korea is selected. The research framework consists of four components: 1) strategic plan dimension , 2) organizational environment dimension, 3) implementation process dimension, and 4) IT dimension. On this framework, to implement ERP systems successfully, the analysis of the results clearly suggests appropriate planning, top management support, change management, appropriate methodology , ERP specialist commitment, management of standard process and master data, and the extent of IT localization.