• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.34 no.1
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• pp.12-21
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• 2002

The effect of soft nip calendering variables including pressure, temperature, nip residence time and moisture on newsprint properties was investigated. The change of bulk, opacity, smoothness, and gloss were determined. It was found that the influence of calendering pressure and temperature are more significant compare the Influence of sheet moisture content and nip residence time on newsprint properties. Calendering conditions of 16$0^{\circ}C$ of temperature, 78kg$_{f}$/cm of line load and 4ms of nip residence time were considered to be optimum conditions to obtain reasonable gloss and smoothness while minimizing the loss of bulk and opacity for newsprint.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.41 no.5
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• pp.1-7
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• 2009

Oxidized acetate starch was synthesized from corn oxidized starch and vinyl acetate. The sizing concentration and degree of substitution of modified starch on surface strength, smoothness and water resistance of the paper have been studied. The results showed that the surface strength, smoothness and other properties of paper sized by oxidized acetate starch is better than that of oxidized starch. When the degree of substitution of modified starch is from 0.04 to 0.14, the properties of paper sized by oxidized acetate starch have been improved more effectively.

• Bulletin of the Korean Mathematical Society
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• v.52 no.2
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• pp.593-601
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• 2015

Let $f{\in}C^r$ ([-1,1]), $r{\geq}0$ and let $L^*$ be a linear left fractional differential operator such that $L^*$ $(f){\geq}0$ throughout [0, 1]. We can find a sequence of polynomials $Q_n$ of degree ${\leq}n$ such that $L^*$ $(Q_n){\geq}0$ over [0, 1], furthermore f is approximated left fractionally and simulta-neously by $Q_n$ on [-1, 1]. The degree of these restricted approximations is given via inequalities using a higher order modulus of smoothness for $f^{(r)}$.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.32 no.2
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• pp.16-25
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• 2000

The influence of four process parameters of soft nip calendering including calendering pressure, temperature, moisture content and nip residence time on bulk, smoothness and tensile strength of newsprints has been investigated. In addition, the effect of basis weights on calendering responses has been examined. Bulk of newsprints decreased and smoothness increased with the increase of the calendering pressure, temperature, moisture content of the sheets and nip residence time. Improvement in tensile strength was observed when low calendering pressure and high temperature of heat-ing roll were employed. Tensile strength of the newsprint, however, decreased abruptly when the calendering temperature and pressure increased above certain levels due to the rupture of sheet structure, which has been verified by SEM. SEM micrographs also showed that it would be possible to maintain the inner bulk while densifying the fibers on the outer surface of newsprint by adjusting the soft nip calendering variables properly.

• Journal of the Korean Operations Research and Management Science Society
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• v.24 no.3
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• pp.27-37
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• 1999

In just-in-time production systems, U-shaped production lines rather than traditional straight lines are often adopted since they have some advantages. The advantages of U-lines over straight lines are that the workstations required can be reduced and the necessary number of workers can be easily adjusted when the demand rates are changed. In this paper, we present a new heuristic based on genetic algorithm to improve the workload smoothness in the U-line. In the proposed algorithm, a new genetic representation is developed which is specific to the problem being solved. To enhance the capability of searching good solutions, genetic operators are designed by using the problem-specific information and heuristics. Extensive experiments are carried out on well-known test-bed problems in the literature to verify the performance of our algorithm. The computational results show that our algorithm is a promising alternative to existing heuristics.

• Journal of the Korean Applied Science and Technology
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• v.26 no.2
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• pp.124-131
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• 2009

We have produced, characterized and compared different colloidal vehicles based on nanoemulsions. We also have investigated morphology and droplet distribution by means of electron microscope and photon correlation spectroscopy. Nanoemulsion systems characterized by different method on formulations have been obtained. Hydration power has been studied by means of a corneometer, measuring the skin electrical capacitance before and after the application of various type of skin lotions. It has been demonstrated that nanoemulsion with oil or fatty alcohol displayed a pronounced hydration power with respect to the solubilization system. In order to compare the smoothness of the skin after using skin lotion, we have measured the friction force. The skin lotions produced by nanoemulsion technique show improved smoothness of an atopic skin.

• Korean Journal of Mathematics
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• v.25 no.1
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• pp.99-116
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• 2017

The aim of this article is to introduce a new form of Kantorovich $Sz{\acute{a}}sz$-type operators involving Charlier polynomials. In this manuscript, we discuss the rate of convergence, better error estimates. Further, we investigate order of approximation in the sense of local approximation results with the help of Ditzian-Totik modulus of smoothness, second order modulus of continuity, Peetre's K-functional and Lipschitz class.

• Journal of the Earthquake Engineering Society of Korea
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• v.14 no.1
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• pp.1-9
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• 2010

The actual hysteretic behavior of structural elements and systems is closer to smooth hysteretic behavior than piece-wise linear behavior. This paper presents a methodology for computing the constant-ductility inelastic response spectra for smooth hysteretic behaviors. The effect of the hysteretic smoothness on the inelastic response spectra for acceleration, displacement, and input energy is evaluated. The results indicate that increasing smoothness in the hysteretic behavior decreases the inelastic response spectra.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.39 no.5
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• pp.26-31
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• 2007

Hanji is a traditional Korean handmade paper, which has been known in ancient Far East as excellent quality calligraphic paper for more than 1,500 year. Hanji is mostly made of Korean paper mulberry bast fibers, and if properly processed, normally lasts for more than 1,000 years with significant strength and still recognizable calligraphic writings or drawings on it. Dochim is a special way of Hanji calendering process, but is turned out to be quite different from modern calendering (machine calendering) in several aspects. In Dochim process, mechanical impacts were applied vertically to the surface of papers. Compared to the modern calendering, Dochim increased paper gloss much more, but paper smoothness a little less. By the Dochim process, densification occurred and the degree of densification was more sensitive to the fiber type in the Dochim process than in the calendering method.

• Journal of Forest and Environmental Science
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• v.18 no.1
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• pp.97-105
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• 2001

The main objective of this study was to investigate effects of pigment mixed with different ratio on the double coated paper. Mineral pigments such as clay and ground calcium carbonate(GCC) as well as hollow sphere plastic pigment were used to evaluate the physical, optical properties and printabilities of double coated paper. The physical properties such as gloss and smoothness, and the printability(ink gloss) of double coated paper were measured to evaluate the effects of the bottom layer on improving the properties of top layer. The data indicated that the usage of hollow sphere plastic pigment for the bottom layer coating improved the surface properties of double coated paper, and that ink gloss was significantly influenced by the structure of bottom layer even when hollow sphere plastic pigment was used for the bottom layer coating.