• Korean Journal of Computational Design and Engineering
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• v.11 no.6
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• pp.403-411
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• 2006

NURBS surfaces have been widely used in engineering design since it can create a smooth surface using minimal numbers of data. But deformation of the surfaces is quite difficult especially for the detailed modification. Also, NURBS surface deformation processes need many inputs, and it is not easy to be implemented in 3D virtual system. In this paper, both the surface trimming and multi-resolution surface are used for the detailed sculpting including sharp edges of NURBS surface. QuadTree is used to separate cleanly the target surface with the surface for sculpting effect. Simple user strokes are also used for the sculpting target curves and GOMS(Goals, Operators, Methods, Selection Rules) model is applied to verify the efficiency of the proposed sculpting process.

• Proceedings of the Korean Fiber Society Conference
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• 2003.10a
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• pp.35-36
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• 2003

The purpose of this work is to investigate the surface modification of LDPE film via corona discharge treatment and subsequent graft polymerization, and their effect on the resulting dyeability is studied in terms of the surface functional groups, surface energetics, and acid-base interaction between the modified LDPE and the dyes used.

• Elastomers and Composites
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• v.51 no.2
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• pp.113-121
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• 2016

Magneto-rheological elastomer (MRE) is a material which shows reversible and various modulus under magnetic field. Comparing to conventional rubber vibration isolator, MREs are able to absorb broader frequency range of vibration. These characteristic phenomena result from the orientation of magnetic particle (i.e., chain-like formation) in rubber matrix. In this study, silicone rubber was used as a matrix of MREs. Carbonyl iron particle (CIP) was used to give magnetic field reactive modulus of MRE. The surface of the CIP was modified with chemical reactants such as silane coupling agent and poly(glycidyl methacrylate), to improve interfacial adhesion between matrix and CIP. The mechanical properties of MREs were measured without the application of magnetic field. The results showed that the tensile strength was decreased while the hardness was increased with the addition of CIP. Also, surface modification of CIP resulted in the improvement of physical properties of MRE, but the degree of orientation of CIP became decreased. The analysis of MR effect was carried out using electromagnetic equipment with various magnetic flux. As the addition of CIP and magnetic flux increased, increment of MR effect was observed. Even though the surface modification of CIP gave positive effect on the mechanical properties of MRE, MR effect was decreased with the surface modification of CIP due to decrease of CIP orientation. Throughout this study, it was found that the loading amounts of CIP affected the mechanical properties of MRE, and surface property of CIP was an important factor on MR effect of MRE.

• New & Renewable Energy
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• v.16 no.3
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• pp.27-34
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• 2020

This study involved a total budget analysis on the greenhouse gas (GHGs) emissions of landfills, focusing on surface emissions and the effect on emissions reductions of generating landfill gas (LFG) electricity from March 7, 2007 to December 31, 2018. The GHGs reduction effect from the electricity generation using 536.6 × 10³ tCO₂ of CH₄ was only 5.8% of the GHGs from surface emissions of 9,191 × 10³ tCO₂. In the total budget, the collection ratio should be over 95% if the reduction effect is greater than the surface emissions. The correlation coefficient for the relationship between the LFG collection ratio and GHGs reduction was -0.89. An additional effect of lowering CH₄ content may occur if the surface emitting flux of LFG decreased with an increase in the collection ratio. The unit reduction effect of GHGs by suppressing surface emissions was 4174 tCO₂/TJ. This was far greater than that of LFG power generated (54.3 tCO₂/TJ), demonstrating that surface emission control is the most important measure by which to mitigate GHGs emission.

• The Journal of Advanced Prosthodontics
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• v.16 no.1
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• pp.25-37
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• 2024

PURPOSE. To investigate the effect of sintering programs and surface treatments on surface properties, phase transformation and flexural strength of monolithic zirconia. MATERIALS AND METHODS. Zirconia specimens were sintered using three distinct sintering programs [classic (C), speed (S), and superspeed (SS)] (n = 56, each). One sample from each group underwent scanning electron microscopy (SEM) and grain size analysis following sintering. Remaining samples were divided into five subgroups (n = 11) based on the surface treatments: control (CL), polish (P), glaze (G), grind + polish (GP), and grind + glaze (GG). One sample from each subgroup underwent SEM analysis. Remaining samples were thermally aged. Monoclinic phase volume, surface roughness, and three-point flexural strength were measured. Monoclinic phase volume and surface roughness were analyzed by Kruskal-Wallis and Dunn tests. Flexural strength was analyzed by two-way ANOVA and Weibull analysis. The relationships among the groups were analyzed using Spearman's correlation analysis. RESULTS. Sintering program, surface treatment, and sintering × surface treatment (P ≤ .010) affected the monoclinic phase volume, whereas the type of surface treatment and sintering × surface treatment affected the surface roughness (P < .001). Type of sintering program or surface treatment did not affect the flexural strength. Weibull analysis revealed no significant differences between the m and σ_o values. Monoclinic phase volume was positively correlated with surface roughness in the SGG and SSP groups. CONCLUSION. After sintering monolithic zirconia in each of the three sintering programs, each of the surface treatments can be used. However, for surface quality and aging resistance, G or GG can be recommended as a surface finishing method.

• Journal of Environmental Impact Assessment
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• v.19 no.4
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• pp.397-407
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• 2010

The increase of the solar reradiation from urban areas relative to suburban due to urbanization heats up the air temperature in urban areas and this is called the urban heat island (UHI) effect. This UHI effect has a positive relationship with the degree of urbanization. Through the studies on UHI using the satellite imagery, the effect of the surface heat radiation was observed by verifying the relationship between the air temperature and the land cover types (surface materials such as urban, vegetation, etc.). In this study, however, the surface temperature distribution was studied in terms of land use types for Seoul. Using land use types, the surface temperature in urban areas such as residential, industrial, and commercial areas in Yeongdeungpo, highly packed with industrial and residential buildings, was maximum $6^{\circ}C$ higher than in the bare ground, which indicated that the surface temperature reflected the pattern of the human-consumed energy on the areas and showed that one of the important causes influencing the air temperature except the surface heat reradiation by the sun is the anthropogenic heat. Also, the effect due to the restoration of the Chunggae stream on UHI was investigated. The average surface temperature for the Chunggae stream was reduced about $0.4^{\circ}C$ after restoration. Considering that each satellite image pixel includes mixture of several materials such as concrete and asphalt, the average surface temperature might be much lower locally reducing UHI near the stream.

• Journal of the Korean Society for Precision Engineering
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• v.31 no.4
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• pp.353-358
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• 2014

This paper reports a simple, yet effective 1-step surface modification method for stainless steel. Electrochemical etching in dilute Aqua Regia forms hierarchical micro and nanoscale structure on the surface. The surface becomes highly hydrophobic (${\sim}150^{\circ}$) as a result of the etching in terms of static contact angle (CA). However the liquid drops easily pinned on the surface because of high contact angle hysteresis (CAH), which is called a "petal effect": The petal effect occur because of gap between surface microstructures, despite of intrinsic hydrophobicity of the base material. The pore size and period of surface structure can be controlled by applied voltage during the etching. This method can be applied to wide variety of industrial demand for surface modification, while maintaining the advantageous anti-corrosion property of stainless steel.

• Proceedings of the KSRS Conference
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• 2008.10a
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• pp.68-71
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• 2008

Our goal is to obtain a better scientific understanding how to define the nature and role of remotely sensed land surface parameters and energy fluxes in the heat island phenomena, and local and regional weather and climate. By using the MODIS visible and thermal imagery data and analyzing the surface energy flux images associated with the change of the landcover and landuse in study area, we will estimate and present how significant is the magnitude of the heat island heat effect and its relation with the surface parameters and the energy fluxes in Taiwan. To achieve our objective, we used the energy budget components such as net radiation, soil heat flux, sensible heat flux, and latent heat flux in the study area of interest derived form remotely sensed data to understand the island heat effect. The result shows that the water is the most important component to decrease the temperature, and the more the consumed net radiation to latent heat, the lower urban surface temperature.

• Journal of Distribution Science
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• v.18 no.10
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• pp.77-87
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• 2020

Purpose: This study was done to analyze the effect of supervisor-focused impression management behavior of the airline cabin crew on perceived customer empathy. It focused on verifying dual meanings of the crew's emotional expression divided into surface acting and deep acting. Research design, data and methodology: The survey was conducted on cabin crews of two major Korean airlines. The reliability and validity of each variable used in the questionnaire were verified. Then, each hypothesis was analyzed through multiple regression analysis. Results: Firstly, the crew's supervisor-focused impression management behavior had a significant effect only on surface acting of the crew's emotional labor behavior. Among the crew's supervisor-focused IM behaviors, verbal IM behavior had a greater influence on surface acting than non-verbal IM behavior. Secondly, there was no relationship between the crew's supervisor-focused IM behavior and the crew's deep acting. Thirdly, the crew's emotional labor behavior (surface acting & deep acting) had a significant effect on perceived customer empathy. Fourth, the crew's deep acting had a greater influence on perceived customer empathy than surface acting. Conclusions: Cabin crews receive double evaluation from their immediate supervisors and customers. As a result, it was confirmed that the crew's supervisor-focused IM behavior, the crew's emotional labor behavior, and perceived customer empathy were connected process.

• Journal of the Korean Magnetics Society
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• v.21 no.4
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• pp.141-146
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• 2011

We will introduce the surface magneto-optic Kerr effect (SMOKE), which is one of the most helpful experimental methods in the area of surface magnetism for the last two decades. The basic magnetic characteristics of magnetic thin film is the most essential part for the further understanding and application. For example, the possibility of the realization of ferromagnetism for a single layer of iron, its Curie temperature far below that of bulk iron, and the direction of easy axis are the fundamental questions for the spintronic application. SMOKE is an efficient method to answer for the questions above.