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951.
952.
Park Ji-Woo Ku Tae-Wan Kim Jeong Kim Kwang-Ho Kang Beom-Soo 《Journal of Mechanical Science and Technology》2016,30(5):2203-2210
Journal of Mechanical Science and Technology - Flexible forming technology such as Multi-point dieless forming (MDF) has benefits for the sheet metal field because it can implement a variety of... 相似文献
953.
Junghun Kim Sangkyu Park Heecheon Cho Junsang Kim Jae Young Choi 《Telematics and Informatics》2017,34(2):540-547
South Korea has the highest expenditure on telecommunications among OECD countries, drawing national attention to the issue of reducing high prices. In response, the Korean government enacted the Mobile Device Distribution Improvement (MDDI) Act to eliminate information asymmetry by limiting mobile carriers’ mobile handset subsidies to consumers. This study examined factors affecting public trust in the MDDI based by analyzing responses to a questionnaire survey using the ordered probit model. The results show that the knowledge, expectations, and perceived effects of the MDDI have a meaningful effect on public trust in the policy. The results of this study confirm that it is essential for governments to promote their policies by continuously educating the public, especially in this case because the policy has a direct effect on telecommunications expenditures. 相似文献
954.
Jong Min Park Chang Young Jung Wang Yao Cheol Jun Song Jae Yun Jaung 《Coloration Technology》2017,133(2):158-164
Nine yellow azo dyes were designed and synthesised by using different diazo components and pyridonyl coupling components for application in dye–pigment hybrid colour filters for liquid crystal displays. The synthesised dyes were characterised by proton nuclear magnetic resonance and elemental analysis. The thermal stability was examined by thermogravimetric analysis, and solubility was estimated in industrial solvents such as N-methyl-2-pyrrolidone and propylene glycol methyl ether acetate. The dyes, which exhibited suitable physical properties for use in a dye–pigment hybrid colour filter, were fabricated into colour filters, and their optical properties were measured. 相似文献
955.
Roll-to-roll (R2R) slot-die coating systems are mostly devoted to the mass manufacture of printed electronics. This study examined the correlation among the operating conditions, thickness, and width of the patterned strip fabricated by the R2R slot-die system. A full factorial experiment was conducted to screen for effective parameters. The velocity of a moving substrate was found to be the most dominant parameter affecting the thickness and width of the patterned strips. The flow ratio of the supply to the slot-die, and gap between substrate and slot-die did not affect the width of the strip, but affected the thickness; therefore, the flow ratio and gap can be employed for the independent patterning of thickness against width. In addition, it was proposed to determine the R2R process conditions, such as gap, velocity, and flow ratio for the desired thickness and width of the patterned strips. 相似文献
956.
Hoon Chae Park Hang Seok Choi Ji Eun Lee 《Korean Journal of Chemical Engineering》2016,33(4):1159-1169
Rapid quenching of volatiles in fast pyrolysis is important for achieving high yield and quality of the bio-oil product, but few studies have examined the condensation of volatiles and their related heat exchangers. Accordingly, we have studied the condensation characteristics of volatiles by varying heat transfer conditions in a direct contact heat exchanger. As the mass flow rate ratio of quenching oil to pyrolysis gas increased, the heat transfer rate and yield of bio-oil increased. The heat transfer rate and yield of bio-oil reached a maximum value at an intermediate air-to-quenching oil mass flow rate ratio. Additionally, the heat transfer rate and yield of bio-oil decreased as the temperature of the quenching oil increased. Experiments were also conducted to derive an empirical relationship for the volumetric heat transfer coefficient for direct contact heat exchangers. 相似文献
957.
Jae Mo Yang Byung Seok Ko Chulhwan Park Byungtae Yoo Dongil Shin Jae Wook Ko 《Korean Journal of Chemical Engineering》2014,31(3):393-401
To increase awareness of safety in facilities where hazards may exist, operators, managers, and executive officers on the site should be able to monitor such facilities. However, most compressed natural gas (CNG) service stations in Korea use only local-mode monitoring, with only on-site operators to monitor the facility. To complement this local-mode monitoring, an online safety management system called Ubiquitous-gas safety management system (U-GSMS) was developed. The U-GSMS consists largely of software and hardware. The software consists of systems that can manage safety and operations, while the hardware consists of sensors installed in the gas facility and wireless communication systems using a ubiquitous sensor network (USN) technology that facilitates communication between sensors as well as between sensors and other devices. As these systems are web-based, on-site operators as well as managers and executive officers at the headquarters can more effectively and efficiently perform monitoring and safety management. 相似文献
958.
This study examined the influence of triethyl and tributyl phosphite (TEP and TBP) additives on the electrochemical performance
of lithium-ion cells. The cell performance of the TEP- and TBP-containing electrolytes was evaluated by cyclic voltammetry,
thermogravimetric analysis, electrochemical impedance spectroscopy, Fourier transform infrared spectroscopy and scanning electron
microscopy. The flammability of the electrolytes was also investigated by measuring the self-extinguishing time of the electrolytes.
The results showed that the TEP and TBP additives suppressed the flammability of the electrolyte, with a significant improvement
in cell performance observed for the TEP additive. In addition, TEP and TBP additives improved the thermal stability of the
battery and its electrochemical cell performance. Overall, 5 wt% TEP and TBP can be used as a flame-retarding additive to
improve the cell performance of Li-ion batteries due to the decrease in cell impedance and SEI formation. 相似文献
959.
Hyun-Joo Oh No-Wook Park Sung-Soon Lee 《International journal of remote sensing》2013,34(10):3211-3231
The aim of this study is to extract landslide-related factors from remote-sensing data, such as Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) satellite imagery, and to examine their applicability to landslide susceptibility near Boun, Korea, using a geographic information system (GIS). Landslide was mapped from interpretation of aerial photographs and field surveying. Factors that influence landslide occurrence were extracted from ASTER imagery. The slope, aspect and curvature were calculated from the digital elevation model (DEM) with 25.77 m root mean square error (RMSE), which was derived from ASTER imagery. Lineaments, land-cover and normalized difference vegetation index (NDVI) layers were also estimated from ASTER imagery. Landslide-susceptible areas were analysed and mapped using the occurrence factors by a frequency ratio and logistic regression model. Validation results were 84.78% in frequency ratio and 84.20% in logistic regression prediction accuracy for the susceptibility map with respect to ground-truth data. 相似文献
960.
Chan-Hee Park Tae-Hyung Kim Do-Hee Lee Leonard D. Tijing Mi-Hwa Yu Sang-Don Moon Cheol Sang Kim 《Metallurgical and Materials Transactions A》2012,43(9):3006-3010
We report here for the first time the use of magnetic polishing to improve the surface finish of titanium-nickel (TiNi) stents for better performance. We investigated the effects of polishing time and rotational speed on the average surface roughness, surface chemical contents, and push-out load of stents. The magnetically polished stents show a decrease of 2.3 to 17.9?pct in surface roughness and a lower push-out load for stent deployment from the catheter. 相似文献