• Proceedings of the KSME Conference
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• 2005.11a
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• pp.140.2-140.2
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• 2005

• Proceedings of the Korean Society of Marine Engineers Conference
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• 2012.06a
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• pp.254-254
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• 2012

• Transactions of the Korean Society of Mechanical Engineers A
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• v.36 no.11
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• pp.1381-1389
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• 2012

The object of this study considers corrosion fatigue improvement of 7075-T6 aluminum by using shot peening treatment on 3.5% NaCl solution at room temperature. Aluminum alloy is generally used in aerospace structural components because of the light weight and high strength characteristics. Many studies have shown that an aluminum alloy can be approximately 50% lighter than other materials. Mostly, corrosion leads to earlier fatigue crack propagation under tensile conditions and severely reduces the life of structures. Therefore, the technique to improve material resistance to corrosion fatigue is required. Shot peening technology is widely used to improve fatigue life and other mechanical properties by induced compressive residual stress. Even the roughness of treated surface causes pitting corrosion, the compressive residual stress, which is induced under the surface layer of material by shot peening, suppresses the corrosion and increases the corrosion resistance. The experimental results for shot peened specimens were compared with previous work for non treated aluminum alloy. The results show that the shot peening treatment affects the corrosion fatigue improvement of aluminum alloys and the induced compressive residual stress by shot peening treatment improves the resistance to corrosion fatigue.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.31 no.7
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• pp.63-68
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• 2003

Shot peening process is most often used to improve the fatigue properties of metal parts, In order to achieve an optimum, repeatable, and reliable fatigue enhancement from the shot peening process, the important shot peening parameters must be optimized, In this paper, the optimum peening intensity(Almen intensity) condition is investigated by experiment. Rotary bending fatigue test has been adopted to investigate the effects of optimum peening on the fatigue characteristics, Experimental results show that the fatigue strength and fatigue life has been tremendously increased by optimum-peening treatment. However, the fatigue strength and fatigue life has been decreased by under or over peening.

• Journal of Digital Convergence
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• v.16 no.5
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• pp.419-424
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• 2018

Match cut is the montage technique that is widely used in the image media. This technique is versatile to generate the receivers a variety of meanings. In this article, the match cut shorts applied in the movie, Bram Stoker's Dracula, were analyzed based on the meanings occurred between the shorts. In addition, the analysis methods were based on the philosophical issues of Gilles Deleuze which had been analyzed focusing on the generation competency. Also, Francis Bacon's paintings, 'painting' (1946) and 'self-portrait' (1969) demonstrating similar meanings were compared to assist understanding. Upon the analyses of these two media, the meanings of 'becoming' that had the feature of nomadism between the shorts and occurred in the process of combined generation were analyzed. Therefore, match cut occurred in the image media was found to function to the receivers in a variety of ways and the degree of its utilization was not limited upon this analysis.

• Journal of Broadcast Engineering
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• v.21 no.6
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• pp.965-976
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• 2016

Recently studies about audio-visual immersion are being carried out due to development of digital video but studies analysing quantitatively the content or climax of video has not carried out. The paper is analysed quantitatively by using shot size, camera angle, camera direction and camera position, objective & subjective which is general component of video expression. We can see the climax effects in the video destroying the principles because there is a rule when they use the component. This thesis analyses shot-list based on video expression in existing movies therefore it can analyse quantitatively several method commonly used in order to make the climax. These suggesting method that can find the part of climax based on analysis of shot-list can be used when you search the specific part of video like long movie or when you search the genre of the movie or when you index the genre. Also it can be very effective in various information services companies offering climax movie which is searched.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.35 no.11
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• pp.1369-1375
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• 2011

Shot ball impacts to materials cause residual compressive stress on their surfaces. Improving the fatigue strength of a material that has this residual compress stress is the purpose of the shot peening process. A numerical study was performed to evaluate the effect of the strain rate sensitivity and hardness of the shot ball on the residual compressive stress. We calculated the residual compressive stress due to multiple impact shot peening using ABAQUS 6.9-1. AISI 4340 steel was the material used in this study. We compared the effects of high strain rate sensitivities and low strain rate sensitivities and found that when the material's sensitivity to the strain rate increased, the residual compressive stress decreased. In addition, the residual compressive stress of low-hardness material is higher than that of high-hardness material.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.40 no.12
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• pp.987-995
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• 2016

In this study, the effects of shot peening (SP) on the Vickers hardness of $ZrO_2$ were studied. The size of the shot balls were ${\phi}180{\mu}m$ and ${\phi}300{\mu}m$. The Vickers hardness was measured using an indentation load of 98 N and 294 N. The Vickers hardness was evaluated using Weibull statistical analysis. The scale parameters were significantly evident from the indentation load of 98 N and the shot ball of ${\phi}180 {\mu}m$. Generally, the shape parameters were also evident from the small short ball (180sp). Thus, it is shown that the introduction of a compressive residual stress by SP is an effective technique for increasing the mechanical properties of $ZrO_2$.

• The Journal of the Korea Contents Association
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• v.17 no.9
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• pp.173-183
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• 2017

In this research, analysis based on VR journalism outlet the New York Times' was carried out. The image analysis of was done through the frames of angle, shot (size, length, movement), and limited user-directed interaction (point, sound). The result of this is as follows. Firstly, the direction was done using a basis of normal and low angles. Secondly, it was able to be confirmed that the shooting was done in order by medium, full, and long shot. Thirdly, with regard to the length of the shot, most direction was done through long takes. Fourthly, most images came to consist of fixed shots. Lastly, this is limited user-directed interaction. This may be separated into 2 aspects: sound, and movement of the independent free agent. Through these, interaction was guided through free point of view concerning realistic situations to point of view guidance and users. This research may be referred to as foundational research for the further advancement of in-depth discussion pertaining to VR journalism.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.35 no.9
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• pp.1119-1129
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• 2011

Shot-peening effects on the fatigue behavior of bearing steel were investigated under the high cyclic loading. Hourglass shape specimens were made of bearing steel(JIS-SUJ2) for rotary bending fatigue tests. Two kinds of treatments were performed : a heat treatment and a shot-peened surface treatment after the heat treatment. The fracture surfaces of specimens were classified into two types of fracture mode : the surface fracture mode induced by a surface defect and the internal fracture mode induced by a nonmetallic inclusion. Inclusion depth and shape affected considerably the fatigue life. Shot-peening treatment improved much the fatigue life of the bearing steel under low and high levels of cyclic loads. Probabilistic-stress-life (P-S-N) curves were suggested for the reliable fatigue life estimation of the improved bearing steel.