• The Transactions of the Korea Information Processing Society
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• v.7 no.8
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• pp.2520-2527
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• 2000

An improved transition density propagation method for power estimation is proposed. The power estimation for the zero delay model is a proper criteria for the.lower boutldlIry for power consumption. A transition propagation method, including the zero delay model as a lower boundary for power stimation was studied. However, there were some redundancy factors in the process of transition density propagation. Hence this paper will explore the transition density propagation behavior to eliminate the redundancy factors and present theirriprQved estimation methodology for the signal transition density. The experiments show that the proposed method has comparably better estimation accuracy than the conventional methods.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.29 no.3 s.234
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• pp.411-417
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• 2005

Surface texturing of tribological application is another attractive technology of friction reducing. Also, reduction of friction is therefore considered to be a necessary requirement for improved efficiency of machine. In this paper attempts to investigate the effect of density for micro-scale dimple pattern using photolithography on bearing steel flat mated with pin-on-disk. We demonstrated the lubrication mechanism for a Stribeck curve, which has a relationship between the friction coefficient and a dimensionless parameter for lubrication condition. It is found that friction coefficient is depended on the density of surface pattern. It was thus verified that micro-scale dimple could affect the friction reduction considerably under mixed and hydrodynamic lubrication conditions from based on friction map. Lubrication condition regime has an influence on the friction coefficient induced the density of micro dimple.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2001.04a
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• pp.1121-1124
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• 2001

In this study, we verify th effects of pattern density on interlayer dielectric chemical mechanical polishing process based on the analysis of Preston's equation and confirm this analysis by several experiments. Appropriate modeling equation, transformed form Preston's equations used in glass polishing, will be suggested and described the effects of this modeling during pattern wafer ILD CMP. Results indicate that the modeling is well agreed to middle density structure of the die in pattern wafer, but has some error in low and high density structure of the die. Actually, the die used in Fab, was designed to have a appropriate density, therefore this modeling will be suitable for estimating the results of ILD CMP.

• Geomechanics and Engineering
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• v.23 no.5
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• pp.493-502
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• 2020

The prediction of soil response under repetitive mechanical loadings remains challenging in geotechnical engineering applications. Modeling the cyclic soil response requires a robust model validation with an experimental dataset. This study proposes a unique method adopting linearity of model constant with the number of cycles. The model allows the prediction of the terminal density of sediments when subjected to repetitive changes in pore-fluid pressure based on the two-surface plasticity. Model simulations are analyzed in combination with an experimental dataset of sandy sediments when subjected to repetitive changes in pore fluid pressure under constant deviatoric stress conditions. The results show that the modified plastic moduli in the two-surface plasticity model appear to be critical for determining the terminal density. The methodology introduced in this study is expected to contribute to the prediction of the terminal density and the evolution of shear strain at given repetitive loading conditions.

• Journal of the Korean Data and Information Science Society
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• v.16 no.4
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• pp.1159-1165
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• 2005

Basu et al. (1998) proposed a new density-based estimator, called the minimum density power divergence estimator (MDPDE), which avoid the use of nonparametric density estimation and associated complication such as bandwidth selection. Woodward et al. (1995) examined the minimum Hellinger distance estimator (MHDE), proposed by Beran (1977), in the case of estimation of the mixture proportion in the mixture of two normals. In this article, we introduce the MDPDE for a mixture proportion, and show that both the MDPDE and the MHDE have the same asymptotic distribution at a model. Simulation study identifies some cases where the MHDE is consistently better than the MDPDE in terms of bias.

• Journal of IKEEE
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• v.19 no.1
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• pp.80-86
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• 2015

There are many studies and products using a test paper impregnated with chemical solution can react with ozone. The color of a test paper can indicate the concentration of ozone. The purpose of this research is to design and manufacture a system using ultraviolet light source to measure the ozone density. This new technique is based on the characteristic of decomposition from ozone into oxygen under ultraviolet light. We used two sources of ultraviolet light including UV lamp and UVLED to determine the decomposition of ozone. This system is built with the electronic components, sensors and sealed pump tube to measure the ozone density in units of $g/cm^3$,ppm,ppb. In this paper,, we present some initial results of measuring the ozone density from ozone generator after completing inspection for safety.

• Proceedings of the KIEE Conference
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• 2002.11d
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• pp.171-173
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• 2002

This paper describes the open frame type high power density switching converter. It is based on active clamp forward converter with synchronous rectifier, and packaged by using the open frame and multi-layer printed circuit board (PCB) techniques to achieve the high power density. Furthermore, windings of transformer and inductor are also realized by multi-layer PCB so that it achieves the higher power density. Through the experiment on the proto-type converter of 50[W], it is confirmed that power density of $50[W/in^3]$ and maximum efficiency of over 91 [%] are obtained.

• Journal of the Korean Society of Tobacco Science
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• v.11 no.2
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• pp.233-240
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• 1989

This experiment was carried out to select of heterokaryon based on the different buoyant densities of protoplasts. Protoplats were isolated from cultured cells (calli) of Nicotiana tobacum(cv. BY4) and from mesophyll cells of N. glauca. The two types of protoplats were fractionated by centrifugation in an iso-osmotic (770 mOs/kg. H2O) density gradients condition. Major difference in the buoyant density exists between two types of protoplasts isolated from different cells. The mesophyll protoplasts were fractionated in the higher gradient interphases than that of callus protoplasts. The two types of fractionated protoplasts were fused with 40% polyethylene glycol (PEG), and the protoplasts treated with PEG were separated by centrifugation in the same density gradients condition. The heterokaryons were fractionated in the intermediate density gradients.

• Proceedings of the Korean Geotechical Society Conference
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• 2009.03a
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• pp.792-797
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• 2009

The stress-strain characteristics of compacted bentonite are investigated using experimental triaxial compression test by Hoek-cell. Special attention given to various dry density and water absorption ratio. Based on the test results, it is shown that the stress-strain relationship of compacted bentonite is highly influenced by dry density and water absorption ratio. Also, characteristics of Bentonite is similar to the clay rather than sand. Strength of compressed Bentonite increases with higher dry density. It shows maximum strength value, if in a same condition with dry density and constrain pressure. So we determine that value as the optimistic moisture contents for the maximun strength of compressed Bentonite.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.53 no.11
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• pp.566-571
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• 2004

Pulse modulation technique provide additional controling method for electron temperature and density in rf and microwave processing plasma. Transient characteristics of electron density and temperature have been measured in pulse modulated rf inductively coupled argon plasma using simple probe circuit. Electron temperature relaxation is clearly identified in the after glow stage. Controllability of average electron temperature and density depends on the modulation frequency and duty ratio. Numerical calculation of time-dependent electron density and temperature have been performed based on the global model. It has been shown that simple langmuir probe measurement method used for continuous plasma is also applicable to time-dependent measurement of pulse modulated plasma.