• Proceedings of the Korean Society of Precision Engineering Conference
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• 2002.05a
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• pp.628-631
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• 2002

This paper has executed FE-analysis to review the feasibility for developing the process, which produces the narrow-cubic type cans, using the Backward Impact Extrusion process instead of using current process, multi-stage deep drawing. Proposes an analysis method by applying ALE(Arbitrary Lagrangian-Eulerian) description to non-axisymmetric extrusion. which is appreciated as one of good solution to mesh distortion in case of the large deformation plasticity process that has mass flux, and considers the factors which affects forming-loads related to punch velocity and fulid status of material.

• Steel and Composite Structures
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• v.8 no.4
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• pp.281-296
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• 2008

Visco-elastic material and thin metals were adhered to plate structures, forming the composite components that are similar to the sandwich plates, called constrained layered damped (CLD) plates. Constrained layer damping has been utilized for years to reduce vibration, and advances in computation and finite element analysis software have enabled various problems to be solved by computer. However, some problems consume much calculation time. The vibration equation for a constrained layered damped plate with simple supports and an impact force is obtained theoretically herein. Then, the results of the vibration equation are compared with those obtained using the finite element method (FEM) software, ABAQUS, to verify the accuracy of the theory. Finally, the 3M constrained layer damper SJ-2052 was attached to plates to form constrained layered damped plates, and the vibration equation was used to elucidate the damping effects and vibration characteristics.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.26 no.5
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• pp.813-821
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• 2002

Glass fiber reinforced PET matrix composite was manufactured by rapid press consolidation technique as functions of temperature, pressure and time in pre-heating, consolidation and solidification stages. The optimal manufacturing conditions for this composite were discussed based on the void content, tensile, interlaminar shear and impact properties. In addition, the levels of crystallinity with various manufacturing conditions were measured using differential scanning calorimetry to investigate the mechanical properties of this composite material as a function of crystallinity. Among many processing parameters, the mold temperature and the cooling rate after forming were found to be the most critical factors in determining the level of crystallinity and mechanical properties. The level of crystallinity affects the tensile properties to some degree. However, impact properties are affected much more. It also affects the degree of ductility, which determines the impact energy of this material.

• Journal of Microbiology and Biotechnology
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• v.28 no.1
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• pp.77-86
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• 2018

The human pathogen and food spoiler Bacillus cereus can form biofilms that act as a persistent source of contamination, which is of public health concern. This study aimed to understand how the source of isolation might affect the behavior of biofilm formation. Biofilm formation abilities of 56 strains of B. cereus isolated from different environments, including human food poisoning, farm, and food, were determined. Crystal violet assay results revealed significant (p < 0.05) differences in biofilm formation abilities among the strains isolated from different sources only at an early stage of incubation. However, strain origin showed no impact on later stage of biofilm formation. Next, correlation of the group of isolates on the basis of their biofilm-forming abilities with the number of sessile cells, sporulation, and extracellular polymeric substance (EPS) formation was determined. The number of sessile cells and spores in biofilms was greatly influenced by the groups of isolates that formed dense, moderate, and weak biofilms. The contribution of extracellular DNA and/or proteins to EPS formation was also positively correlated with biofilm formation abilities. Our results that the source of isolation had significant impact on biofilm formation might provide important information to develop strategies to control B. cereus biofilm formation.

• Asian Journal of Innovation and Policy
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• v.7 no.1
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• pp.103-130
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• 2018

It is generally understood that clusters are the promoters of innovation and therefore, the attention of researchers has been increasingly to discern the factors driving innovation among the firms in a cluster, especially in a high-tech cluster. In this study, we identify the variables capturing the nature of a firm that possibly impact the absorptive capacity of a firm and subsequently ascertain their impact on the degree of interactions between a firm, and other firms and associated institutions within and outside a cluster, respectively. Furthermore, we probe the influence of these interactions as a whole on firm-level innovation. The study was carried out in the context of Bengaluru, which houses the densely interconnected network of innovation-intensive high-tech manufacturing firms forming a high-tech manufacturing cluster. Data were drawn from 101 high-tech manufacturing firms belonging to electronics, machine tools, electrical and pharmaceutical industries. Based on the cluster analysis and subsequent graphical analysis on each of the three profiled clusters, it was found that size and origin of a firm have significant impact on the degree of firm's interactions. In turn, higher dynamism of firms in terms of degree of interactions led to higher innovation performance.

• The Journal of Industrial Distribution & Business
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• v.10 no.4
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• pp.57-66
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• 2019

Purpose - Present study aimed at investigating the factors that may affect consumers' decision confidence and decision comfort inducing choice commitment taken place at the stage of post-decision/pre-outcome. This study explored whether there are positive effects of dominance and instrumentality of chosen product on the decision confidence, and also identified whether there are positive effects of choice easiness and goal achievement-related affect felt at the chosen product on the decision comfort. Research design, data, and methodology - Portable digital camera as experimental product was used. 260 data were collected from college students. Four were removed from the analyses because they did not complete the questionnaire. Eighteen were removed because they indicated not experiencing the camera in the past. 238 data were used at the analyses to verify hypotheses by structural equation model in AMOS 21.0. Results - First, both of the consumers' decision confidence and decision comfort positively affected choice commitment. Second, the dominance as well as the instrumentality had positive impact upon the decision confidence. Third, the choice easiness and goal achievement-related affect felt at the chosen product had positive impact on the decision comfort. In sum, present study identified the mediation roles of the decision confidence in the effects of both dominance and instrumentality of the chosen product on forming choice commitment, and also found the mediation roles of the decision comfort in the effects of choice easiness and goal achievement-related affect felt at the product on forming choice commitment. Conclusions - Focusing on the stage of post-decision/pre-outcome in decision making process, present study contributes to advancing the choice commitment theories by exploring the positive effects of both dominance and instrumentality of chosen product on the decision confidence, and by finding the positive effects of both choice easiness and goal achievement-related affect felt at the chosen product on the decision comfort. Marketers should promote their products' dominance and instrumentality by showing the superior roles of their product attributes in achieving consumption goal, and should help consumers feel comfort by making choice process easier and giving information that could help feel the goal achievement-related affect at their product chosen.

• Journal of Welding and Joining
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• v.32 no.3
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• pp.11-18
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• 2014

TSV(through silicon via) filling technology is making a hole in Si wafer and electrically connecting technique between front and back of Si die by filling with conductive metal. This technology allows that a three-dimensionally connected Si die can make without a large number of wire-bonding. These TSV technologies require various engineering skills such as forming a via hole, forming a functional thin film, filling a conductive metal, polishing a wafer, chip stacking and TSV reliability analysis. This paper addresses the TSV filling using Cu electrodeposition. The impact of plating conditions with additives and current density on electrodeposition will be considered. There are additives such as accelerator, inhibitor, leveler, etc. suitably controlling the amount of the additive is important. Also, in order to fill conductive material in whole TSV hole, current wave forms such as PR(pulse reverse), PPR(periodic pulse reverse) are used. This study about semiconductor packaging will be able to contribute to the commercialization of 3D TSV technology.

• The Bulletin of The Korean Astronomical Society
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• v.43 no.1
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• pp.59.3-59.3
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• 2018

With a recent observational study of extended Lyman-alpha halos around individual high-z star-forming galaxies by Leclercq et al. (2017) using MUSE, we perform radiative transfer calculations to see if Lyman-alpha scattering can explain the spatial extents of the halos together with their spectra. We adopt a spherically-symmetric halo model in which Lyman-alpha sources and neutral hydrogen (HI) medium have exponential density distributions. The HI medium is set to have outflowing motion based on a momentum-driven wind scenario in a gravitational potential well. We run our Lyman-alpha radiative transfer code, LaRT, upon this halo model for various sets of parameters regarding the HI medium such as temperature, optical depth, density scale radius, outflow velocities, and dust content. We analyze simulation results to see the impact of each parameter on Lyman-alpha spectra and surface brightness profiles, and degeneracies between the parameters. We also find a parameter set that best reproduces simultaneously the observed spectra and surface brightness profiles of the MUSE Lyman-alpha halos.

• The Plant Pathology Journal
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• v.35 no.3
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• pp.200-207
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• 2019

Fusarium head blight (FHB) is a devastating wheat disease with a significant economic impact. Fhb1 is the most important large effect and stable QTL for FHB resistance. A pore-forming toxin-like (PFT) gene was recently identified as an underlying gene for Fhb1 resistance. In this study, we developed and validated a PFT-based Kompetitive allele specific PCR (KASP) marker for Fhb1. The KASP marker, PFT_KASP, was used to screen 298 diverse wheat breeding lines and cultivars. The KASP clustering results were compared with gelbased gene specific markers and the widely used linked STS marker, UMN10. Eight disagreements were found between PFT_KASP and UMN10 assays among the tested lines. Based on the genotyping and sequencing of genes in the Fhb1 region, these genotypes were found to be common with a previously characterized susceptible haplotype. Therefore, our results indicate that PFT_KASP is a perfect diagnostic marker for Fhb1 and would be a valuable tool for introgression and pyramiding of FHB resistance in wheat cultivars.

• Transactions of Materials Processing
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• v.32 no.4
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• pp.221-227
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• 2023

While tube bending is a conventional forming technique, it is still used to make curved products for load-bearing members or aesthetically pleasing parts in various manufacturing industries such as automotive, aerospace, and others. Whole or local deformation of the final product such as springback, distortion, or local buckling are of interest in metal forming or precision manufacturing. In this paper, the factors affecting the cross-sectional deformation are explored. A 5-axis stretch bending machine was used for two-dimensional bending with extruded AA6082-T4 rectangular tubes. Three different bending sequences were employed: stretch before bending, stretch after bending, simultaneous bending and stretch. Furthermore, by considering both the stretch and bending angle, cross-sectional deformation was also analyzed. It was observed that employing stretch bending techniques can effectively reduce cross-sectional deformation and contribute to overall quality enhancement. Through this study, it was revealed that these factors have an impact on the cross-sectional deformation of the tubes.