• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.18 no.6
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• pp.113-119
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• 2018

This paper relates the AM-NM-MMA algorithm which possible to adaptive equalization performance improvement using the adaptive modulus instead of fixed modulus in the NM-MMA algorithm. The NM-MMA emerged for the tradeoff the MMA and SE-MMA algorithm characteristics, the MMA provides the less residual values in the steady state and have a slow convergence rate, the SE-MMA provides the fast convergence rate and increae the risidual values in the steady state. But the fixed modulus can not give the zero residual values in the perfect equalization state and eqaulization performance were degrade, the adaptive modulus was applied in order to reducing the residual values, and its improved performance were confirmed by simulation. For this, the equalizer output constellation, residual isi, MD, MSE, SER were used for performance index. As a result of computer simulation, the AM-NM-MMA has more good performance in equalizer output signal constellation, residual isi, MD, MSE than the NM-MMA, but not in SER performance.

• Journal of the Chungcheong Mathematical Society
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• v.31 no.3
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• pp.325-331
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• 2018

In this paper, we study which transform preserves the k-hyponormality of weighted shifts. For this, we introduce a new transform, the modulus multiplication transform, and then examine various properties of it.

• Communications of the Korean Mathematical Society
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• v.23 no.4
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• pp.541-548
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• 2008

For a completely bounded linear maps between operator spaces, we introduce numbers which measure the degree of injectivity and subjectivity. The number measuring the injectivity is an operator space analogue of the minimum modulus of a linear map in normed spaces.

• 한국ITS학회:학술대회논문집
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• 2005.11a
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• pp.249-252
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• 2005

• Journal of the Chungcheong Mathematical Society
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• v.16 no.2
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• pp.23-30
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• 2003

In this note, we introduce the concept of the modulus of a curve family in $R^n$ and examine some basic properties. And we study the boundary behavior of quasiconformal mappings on a domain $D{\subset}\bar{R}^n$ and present some geometric applications.

• Journal of the Korean Society for Precision Engineering
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• v.25 no.8
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• pp.88-95
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• 2008

Young's modulus of electroplated nickel thin film is systematically investigated using the resonance method of atomic force microscope. Thin layers of nickel to be measured are electroplated onto the surface of an AFM silicon cantilever and Young's modulus of plated nickel film is investigated as a function of process conditions such as the plating temperature and applied current density. It is found that Young's modulus of plated nickel thin film is as high as that of bulk nickel at low plating temperature or low current density, but decreases with increasing plating temperature or current density. The results imply that the plating rate increases as increasing the plating temperature or current density, therefore, slow plating rate produces a dense plating material due to the sufficient time fur nickel ions to form a dense coating.

• Proceedings of the Korea Concrete Institute Conference
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• 2001.05a
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• pp.37-42
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• 2001

This paper presents the improved elastic modulus equation more appropriate to predict the modulus of elasticity of structural elements designed and made by high-strength concrete. To propose the elastic modulus equation, more than 300 laboratory specimen tests having the range of 5n to 800kgf/$cm^{2}$ in concrete compressive strength were conducted and analyzed statistically. The equation derived in terms of empirical constant, the elastic moduli of coarse aggregate and mix proportions. Comparison of the proposed elastic modulus equation with the previously suggested equations in the ACI363R, and New-RC were also presented to demonstrate the applicability to practice.

• Carbon letters
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• v.10 no.1
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• pp.38-42
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• 2009

This study aims to find a correlation between XRD and Raman result of the oxidized high modulus carbon fibers as a function of its oxidation degrees, and compare with the isotropic carbon fiber reported early. La of the high modulus carbon fiber prepared by oxidation in carbon dioxide gas have been observed using laser Raman spectroscopy. The basic structural parameters of the fibers were evaluated by XRD as well. The La of the original high modulus carbon fibers were measured to be 144 ${\AA}$ from Raman analysis and 135 ${\AA}$ from XRD analysis. La of the 92% oxidized fiber were 168 ${\AA}$ by using Raman and 182 ${\AA}$ by using XRD. There was some correlation between the La value obtained from Raman and XRD. However the La value changes of the high modulus carbon fiber through whole oxidation process showed opposite tendency compare with the isotropic carbon fiber because of the fiber structure basically.

• The Journal of Advanced Prosthodontics
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• v.8 no.3
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• pp.167-171
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• 2016

PURPOSE. This study inspects the effect of incorporating halloysite nanotubes (HNTs) into polymethyl methacrylate (PMMA) resin on its flexural strength, hardness, and Young's modulus. MATERIALS AND METHODS. Four groups of acrylic resin powder were prepared. One group without HNTs was used as a control group and the other three groups contained 0.3, 0.6 and 0.9 wt% HNTs. For each one, flexural strength, Young's modulus and hardness values were measured. One-way ANOVA and Tukey's test were used for comparison (P<.05). RESULTS. At lower concentration (0.3 wt%) of HNT, there was a significant increase of hardness values but no significant increase in both flexural strength and Young's modulus values of PMMA resin. In contrast, at higher concentration (0.6 and 0.9 wt%), there was a significant decrease in hardness values but no significant decrease in flexural strength and Young's modulus values compared to those of the control group. CONCLUSION. Addition of lower concentration of halloysite nanotubes to denture base materials could improve some of their mechanical properties. Improving the mechanical properties of acrylic resin base material could increase the patient satisfaction.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.25 no.1
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• pp.25-31
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• 2001

The theoretical modeling to predict the modulus of elasticity by the shape memory effect of dispersed particles in a metal matrix composite was studied. The modeling approach is based on the Eshelbys equivalent inclusion method and Mori-Tanakas mean field theory. The calculation was performed on the TiNi particle dispersed Al metal matrix composites(PDMMC) with varying volume fractions and prestrains of the particle. It was found that the prestrain has no effect on the Yonugs modulus of PDMMC but the volume fraction does affects it. This approach has an advantage of definite control of Youngs modulus in PDMMCs.