• Journal of the Korean Magnetics Society
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• v.2 no.1
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• pp.50-55
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• 1992

Numerical method for analyzing the reading process in magnetic recording system is described. Hysteresis characteristics must be included in numerical analysis not only recording process but also reading process because of hysteretic behavior of recording media. Algorithm which is consisted of finite clement method for numerical analysis and Preisach model considered to be more appropriate method than Stoner-Wohlfarth model with spin curling mode for describing hysteresis characteristics is constructed. Equations to calculate waveform of reproduced voltage is proposed. Then, this is applied to perpendicular magnetic recording systems with pole type head and double layer media. Waveform of magnetic flux density and reproduced voltage induced in head coil is obtained. If the recording current increase in recording process, magnitude of reproduced voltage in reproducing process saturates. From this saturation curve, value of current which produce maximum voltage can be obtained.

• International Journal of Highway Engineering
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• v.6 no.4 s.22
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• pp.75-89
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• 2004

Long term performance of concrete pavement significantly depends on the given construction and environmental condition. It means that random cracks and extreme crack width due to inappropriate quality control at the early age might lead to decreasing the pavement service life. The temperature and moisture during the construction, cement and aggregate types, curing condition are major components to affect the quality of the concrete pavement at the early age. First of all, the high temperature differential, that is made by increasing air temperature and the heat of cement hydration, is known as the major contributor to severe cracks. In this study, tent covering was used for controlling temperature of the concrete slab. The field measurement data indicates that the effect of the tent covering is very significant to decrease possibilities of random crack occurrence and curling stress and enhance the long-term concrete strength. HIPERPAV(High PERformance PAVing software), a program predicting the strength and stress of an earty-age concrete pavement (72 hour after placement), is used for simulating the effects of tent covering. The HIPERPAVE results showed that the section with the tent covering has higher reliability than the section without the tent covering by 22.5%. In details, reliability is increased 72.5% (without the tent covering) to 95% (with the tent covering).

• Proceedings of the Korea Concrete Institute Conference
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• 1999.10a
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• pp.429-432
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• 1999

The concrete slab on the foundation may have curling and warping deformations due to moisture and temperature gradient of its section. These deformations may change the support conditions of concrete slabs, and cause higher level of stresses than expected. This study was performed to verify the effect of partial support condition of concrete slab on the foundation due to its deformations and to develop the useful analytic method for describing these phenomenons. The partial support condition verified by FWD test results, and it was concluded that the gap model could be useful in analysing the concrete slab with partial support conditions.

• International Journal of Highway Engineering
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• v.10 no.2
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• pp.167-181
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• 2008

A pavement structure analysis model plays a very important role which can correlate input variables to performance models. In this research, a standard shell element model was developed by use of the ABAQUS program so that behaviors of concrete pavements be analyzed. The model was verified in terms of its accuracy by way of comparing the results to those gathered from closed-form Solutions, the Everfe program, and the ABAQUS program with a solid model. Many input variables were analyzed in the model, and the results were stored in a database. Based on the SPSS program, stress equations with respect to temperature and curling effects were developed. All models gave over 0.90 of R2 value except the case considering top-down curling (R2=0.86)

• Transactions of the Korean Society of Mechanical Engineers A
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• v.39 no.10
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• pp.1053-1061
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• 2015

This paper discusses the analysis of the curl deformation behavior when a dynamic force is applied to a tearing tube installed on a flat die to predict the energy absorption capacity and deformation behavior. The deformation of the tips of the curling strips was obtained when the curl tips and tube body are in contact with each other, and a formula describing the energy dissipation rate caused by the deformation of the curl tips is proposed. To improve this formula, we focused on the variation of the curl radius and the reduced thickness of the tube. A formula describing the mean curl radius is proposed and verified using the curl radius measurement data of collision test specimens. These improved formulas are added to the theoretical model previously proposed by Huang et al. and verified from the collision test results of a tearing tube.

• Journal of Ginseng Research
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• v.31 no.1
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• pp.14-22
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• 2007

As the zygotic embryo of North American ginseng (Panax quinquefolius L.) matured during stratification over 203 days it grew from 0.75 to 5.2 mm. Embryo excision and culturing on media containing different concentrations of two growth regulators, gibberellic acid ($GA_3$, 1 to 10 ${\mu}M$) and benzyladenine (BA, 1 to 5 ${\mu}M$), during stratification, showed that shoot and root number and the shoot, root and cotyledon length increased with increased stratification time. Gibberellic acid was the more effective growth regulator for increasing shoot and root number and shoot, root and cotyledon lengths. Immature embryos (stratified for up to 63 days) needed growth regulators for further development. Cultures on $GA_3$ at the last culture date (stratified for 203 days) when embryos were mature, produced multiple shoots but there was no effect of $GA_3$ concentration. Benzyladenine inhibited shoot and root growth regardless of embryo stratification. Growth regulators had little effect on cotyledon length of mature embryos. Embryos cultured on $GA_3$ combined with BA were green on all culture dates whereas greening in the control and BA treatments increased with culture date. The BA treatments induced 100% swelling of the embryos on the final culture date while in the control and $GA_3$ treatments there was no swelling. There was little or no curling in the control and BA treatments and a linear decrease in curling with culture date in the $GA_3$ and $GA_3$ + BA treatments.

• Molecules and Cells
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• v.28 no.2
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• pp.93-98
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• 2009

A plant-specific gene was cloned from melon fruit. This gene was named downward leaf curling (CmDLC) based on the phenotype of transgenic Arabidopsis plants overexpressing the gene. This expression level of this gene was especially upregulated during melon fruit enlargement. Overexpression of CmDLC in Arabidopsis resulted in dwarfism and narrow, epinastically curled leaves. These phenotypes were found to be caused by a reduction in cell number and cell size on the adaxial and abaxial sides of the epidermis, with a greater reduction on the abaxial side of the leaves. These phenotypic characteristics, combined with the more wavy morphology of epidermal cells in overexpression lines, indicate that CmDLC overexpression affects cell elongation and cell morphology. To investigate intracellular protein localization, a CmDLC-GFP fusion protein was made and expressed in onion epidermal cells. This protein was observed to be preferentially localized close to the cell membrane. Thus, we report here a new plant-specific gene that is localized to the cell membrane and that controls leaf cell number, size and morphology.

• International Journal of Highway Engineering
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• v.12 no.3
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• pp.139-146
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• 2010

This research was conducted to analyze the behavior of the post-tensioned concrete pavement (PTCP) system in which weigh-in-motion (WIM) sensors were installed. One lane of PTCP was constructed after removing the existing asphalt pavement. The frictional resistance between the slab and the underlying layer should be small enough for the PTCP slab to properly have prestresses by tensioning. By performing an experimental construction of PTCP, the friction effects and the longitudinal displacements of PTCP under environmental loads were investigated. Based on the knowledge obtained from the experiments, the actual PTCP sections including WIM sensors were constructed and the curling behavior of the system was investigated. As a result, the behavior of the PTCP system was not affected by the existence of WIM sensors, and the appropriate PTCP system when installing WIM sensors in it could be developed.

• International Journal of Highway Engineering
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• v.12 no.4
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• pp.165-174
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• 2010

This study was conducted to evaluate the feasibility of expedite repairing of concrete pavements using precast concrete pavement method and to investigate the effectiveness of slab connection methods. In the demonstration construction, four slabs of jointed concrete pavements were replaced with the precast slabs. First, precast concrete slabs were designed and fabricated, then existing slabs were cut and removed, and finally precast slabs were installed. The slabs were leveled and pockets, holes, and space between the slab bottom and the underlying layer were grouted. From the demonstration construction, details about the design and construction of the precast pavements for repairing of pavements were evaluated. In addition, the slab connection methods such as pocket and hole connection methods were applied in the construction and the slab curling behaviors at the joints that include those connection methods were compared. The results showed that both slab connection methods were applicable, and the hole connection method was superior.

• Journal of the Korea Fashion and Costume Design Association
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• v.24 no.4
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• pp.41-56
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• 2022

This study aims to investigate the actual condition of wearing leggings and the preferred design of down-aging women in their 30s and 40s who have young sensibility, but are starting to enter a middle-aged body type. By analyzing the problems experienced when wearing leggings in this age group, this study intends to provide basic data for the development of a middle-aged female leggings pattern with an improved fit. Therefore, a survey was conducted on 214 women in their 30s and 40s. The results of the survey are as follows. Among down-aging women who want to look younger, leggings are becoming an essential item, but most leggings brands are producing leggings with patterns suitable for women in their 20s. The results of this study also showed that down-aging women in their 30s and 40s mainly purchase and prefer body-fitting leggings. However, they are experiencing discomfort due to 'Y-zone accentuate', 'undergarment accentuate', 'cloth stucking', and 'waist band curling and tightening'. The results indicate that women in their 30s and 40s, who are starting to change to a middle-aged body type, have fit problems. Women in their 20s generally prefer functions that improve the body line, while those in their 30s and 40s prefer functions that improve movement and cover problems caused by the abdomen and the Y-zone area. Therefore, when designing leggings for down-aging women in their 30s and 40s, based on body-fitting leggings, a material with excellent elasticity must be selected. Also develop patterns that solves 'Y-zone accentuate', 'undergarment accentuate', 'cloth stucking', and 'waist band curling and tightening' problems.