• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.12 no.3
• /
• pp.1070-1077
• /
• 2011

This paper is studied on the influence of machining conditions on weldability obtained by ultrasonic machining. The weldability estimation of dissimilar Ni-Cu sheets with the optimization of one-wavelength horn is confirmed by the use of ultrasonic machining. The optimal welding condition with tensile test by setting the ultrasonic machining parameters is suggested and the weldability is estimated by SEM observation and EDX-ray analysis. Experimental studies are worked with the measure of tensile strength and the analysis of SEM photograph after the ultrasonic machining of workpiece. Machining parameters of machining time, pressure, and amplitude are also applied to this paper.

• Asian Journal of Atmospheric Environment
• /
• v.7 no.1
• /
• pp.1-7
• /
• 2013

To establish the method for investigating the behavior of aerosol particles deposited on the leaf surface against fog water under natural conditions, scanning electron microscopy with energy-dispersive X-ray (SEM-EDX) analysis and wash water analysis by ion chromatography after the washing treatment were performed using leaves of white birch collected from low part of the tree crown and the top of the tree in Sapporo City, Hokkaido, northern Japan. Each of collected leaves was divided into two parts according to the treatment performed: leaf surface (adaxial side) was 1) untreated, and 2) washed with deionized water with a pipette. In untreated samples, many particles of various shapes, including soil particles and organic debris, were deposited on the surface. Particles containing S were found on the surface of samples collected from only low part of the tree crown. After the washing treatment, SEM-EDX analysis revealed that soil particles and particles containing S had been washed off with water, although some particles such as soil particles and organic debris still remained on the leaf surface. The major anion such as $SO{_4}^{2-}$ was detected in wash water of all samples, although the peak of S in X-ray spectra was not detected from samples collected at top of the tree. The combination of SEM-EDX analysis with wash water analysis indicated that $SO{_4}^{2-}$ was deposited on the leaf surface in dissolved state and/or in state of submicron particles. These results suggested that fog water could remove soil particles and particles containing S and $SO{_4}^{2-}$ from the leaf surfaces, but not all particles. There was no difference in sampling position in the tree crown. Our study suggested that combination with SEM-EDX analysis and wash water analysis would be effective for investigation of the behavior of particles on the leaf surface against fog water.

• Journal of Korea Society of Digital Industry and Information Management
• /
• v.8 no.3
• /
• pp.199-212
• /
• 2012

This study focuses on the influence of followership on leadership and empowerment, and to verify based on the control variables taken in IT SME's to enhance competitiveness through innovation and improvement plan that have been taken. Because there can be a lot of information to be taken, the laws of Moderated Regression Multiple analysis(MMR) were used. Amos, due to the moderating effect of Structural Equation Modeling(SEM) has been employed to re-verify the results seen with Moderated Regression Multiple analysis. The paper focuses on determining whether transformational leadership or transactional leadership is effective as shown by the levels of empowerment derived from these two types of leadership under study. As a result, both the Moderated Regression Multiple analysis and structural equation model searched information on transformational and followership for empowerment having moderating effects. In the Moderated Regression Multiple analysis, results showed that empowerment for leadership in business in the regulation of followership role appeared not to be seen. However, using the structural equation modeling, moderating effects have been found.

• Proceedings of the Korean Society for Emotion and Sensibility Conference
• /
• 2001.05a
• /
• pp.109-113
• /
• 2001

The purpose of this paper is to propose an analytical method for evaluating user satisfaction of Internet websites using the structural equation model(SEM). This paper is intended to identify critical evaluation factors of user satisfaction for websites to determine criteria for evaluating the websites, and use the criteria to develop a SEM model for quantitatively evaluation of each factors' effects of user satisfaction. The SEM model used 2 variables of usability and good-looks for the evaluation factors of websites user satisfaction and each factors have 4 sub evaluation criteria, 3 portal sites were evaluated to construct the SEM model, and 155 subjects participated the website evaluation using the walk-through and face-to-face survey method. Analysis results showed that the SEM model was statistically significant for all the 3 websites evaluated. Both the usability and good-looks two factors also showed significant effects to user satisfaction of websites and have positive correlation. The user satisfaction was more effected by the usability factor than good-looks, and the simplification and harmonization were the most critical sub-factors of the usability and good-looks.

• Journal of the Ergonomics Society of Korea
• /
• v.22 no.2
• /
• pp.45-56
• /
• 2003

The purpose of this study is to develop the model including multiple causal relationship between factors to evaluate overall user satisfaction and develop an objective method to quantify the impacts and scores of each qualitative factors on overall user satisfaction using Structural Equation Model(SEM) and also test the feasibility to construct a comprehensive website evaluation model including qualitative and quantitative factors. The SEM model used 2 qualitative factors of usability and esthetic factors for the evaluation factors of user satisfaction and select 4 attributes of each factors using factor analysis. 3 shopping mall sites were evaluated to construct the SEM model, and 155 subjects participated the website evaluation using the walk-through and face-to-face survey method. Analysis results showed that the SEM model was statistically significant for all the 3 websites evaluated. Both the usability and esthetic factors showed significant effects to user satisfaction of websites and have positive correlation. The user satisfaction was more effected by the usability factor than esthetic factors, and the simplification and harmonization were the most critical attributes of the usability and esthetic factors.

• Journal of the Korea Institute of Building Construction
• /
• v.17 no.5
• /
• pp.437-444
• /
• 2017

In the composite waterproofing method in which a polyurethane coating waterproofing material is applied on the modified asphalt waterproofing sheet, the organic solvent is diluted in the coating waterproofing material in order to improve the workability. However, since the organic solvent is not volatilized before the curing of the polyurethane coating waterproofing material, the organic solvent causes dissolution of asphalt layer, thereby causing oil leakage. As a result, a polyamide film having a high dissolution resistance property was laminated on modified asphalt sheet, and through testing the dissolution resistance was visually confirmed and quantitative analysis of the polyamide film by SEM-EDX analysis was also used to confirmed the dissolution resistance of the polyamide film.

• Corrosion Science and Technology
• /
• v.23 no.2
• /
• pp.113-120
• /
• 2024

An attempt was made to apply digital image correlation (DIC) strain analysis to in-situ scanning electron microscopy (SEM) observations of bending deformation to quantify local strain distribution inside a ZnMgAl-alloy coating in deformation. Interstitial-free steel sheets were hot-dipped in a Zn-3Mg-6Al (mass%) alloy melt at 400 ℃ for 2 s. The specimens were deformed using a miniature-sized 4-point bending test machine inside the SEM chamber. The observed in situ SEM images were used for DIC strain analysis. The hot-dip ZnMgAl-alloy coating exhibited a solidification microstructure composed of a three-phase eutectic of fine Al (fcc), Zn (hcp), and Zn2Mg phases surrounding the primary solidified Al phases. The relatively coarsened Zn₂Mg phases were locally observed inside the ZnMgAl-alloy coating. The DIC strain analysis revealed that the strain was localized in the primary solidified Al phases and fine eutectic microstructure around the Zn₂Mg phase. The results indicated high deformability of the multi-phase microstructure of the ZnMgAl-alloy coating.

• Proceedings of the KSME Conference
• /
• 2007.05a
• /
• pp.1282-1287
• /
• 2007

The nature of the signal collected by an SEM(Scanning Electron Microscope) in order to form images are all dependent on the detector used to collect them, and the quality of an acquired images is strongly influenced by detector performance. Therefore, the development of detector with high performance is very important for improving on the resolution of SEM. This paper presents the manufacture of secondary electron detector and the optimal position of electron detector through numerical analysis in SEM.

• Proceedings of the IEEK Conference
• /
• 2009.05a
• /
• pp.335-337
• /
• 2009

A scanning electron microscope(SEM) is a system that visualizes complex surface features. The resolution of SEM is affected by each of equipment components. In this study, we examined the effects of the four factors including the beam current, magnification, voltage and working distance. A statistical analysis was conducted to investigate the main and interaction effects. For a systematic characterization, a $2^4$ full factorial experiment was conducted. The $R^2$ of constructed statistical model was 88.9%. The main effect revealed that the current and working distance are dominant factors. Of the interactions, those between the current and voltage yielded the highest interaction. 3D plots generated from the model were used to explore various parameter effects.

• Transactions of the Korean Society of Machine Tool Engineers
• /
• v.16 no.6
• /
• pp.153-158
• /
• 2007

The present study covers numerical analysis of a thermionic scanning electron microscope(SEM) column. The SEM column contains an electron optical system in which electrons are emitted and moved to form a focused beam, and this generates secondary electrons from the specimen surfaces, eventually making an image. The electron optical system mainly consists of a thermionic electron gun as the beam source, the lens system, the electron control unit, and the vacuum unit. For a systematic design of the electron optical system, the beam trajectories are investigated through numerical analyses by tracing the ray path of the electron beams, and the quality of resulting image is evaluated from the analysis results.