• Asia pacific journal of information systems
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• v.30 no.1
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• pp.143-165
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• 2020

The rapid growth of economic transactions generated by live streaming broadcasts ("LSB") has created opportunities for retailers to increase sales. However, little is known about what impact LSB celebrities have on customers and what causes LSB celebrities to become famous. This study aimed to fill this gap by studying the economics of LSBs. This study was conducted through a para-social relationship and attractiveness theory framework. Consequently, social and task attraction were assumed to be the antecedents of the para-social relationship that induced purchase intention. This study examined the impact of relationship rewards, self-disclosure, affective interactivity, informative interactivity, and the amount of information provided on purchase intentions through LSB. Celebrities can use the results of this study to enhance their appeal to fans and promote customers' purchase on e-commerce. This study contributed to the IS field by investigate the impact of para-social relationship on the online shopping context.

• Journal of Korean Institute of Industrial Engineers
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• v.38 no.3
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• pp.220-226
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• 2012

The Electric discharge machining (EDM) process is used to minimize the difference between designed feature and machined feature while the most workpiece is removed through the cutting processes. The tiny-deep hole machining and perpendicular wall machining in mold and die are good applications of EDM. Among EDM equipment, the super drill uses the hollowed electrode to eliminate the debris which causes the second discharge with the electrode and degrades the machining quality. Through the hollow, the high pressured discharge oil is supplied to remove the debris together with the spindle rotation. The thin-hollow electrode tends to easily wear out compared to the sold die-sinking electrode and its wear rate is might not allowed to monitor in real time during discharging. Up to now, the wear amount is measured by off line method, which leads machining time to increase because the hole pass-through moment can be check by visual (manually) with the extra tool path. Therefore, this study suggests the attractive method to evaluate the hole pass-through moment in which the gap voltage and z-axis encoder pulse are monitored to predict the moment. The commercial super drill is used to validate the proposed method and the experiment is carried out.

• Journal of Electrical Engineering and Technology
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• v.12 no.4
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• pp.1605-1610
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• 2017

The electrochemical luminescence (ECL) device was investigated, which has similar structure to the dye-sensitized solar cell. The structure of the ECL cell in this experiment reliably induces a large amount of the oxidation around electrodes. The band gap of the ECL electrode is of 3.0 - 3.2 eV. Titanium dioxide ($TiO_2$) nanoparticle has following properties: a band gap of 3.4 eV, a low-priced material, and 002 preferred orientation (Z-axis). Zinc Oxide (ZnO) nanorod is easy to grow in a vertical direction. In this paper, in order to determine material suitable for the ECL device, the properties of various materials for electrodes of ECL devices such as ZnO nanorod (ZnO-NR) and $TiO_2$ nanoparticle ($TiO_2-NP$) were compared. The threshold voltage of the light emission of the ZnO-NR was 2.0 V which is lower than 2.5 V of $TiO_2-NP$. In the other hand, the luminance of $TiO_2-NP$ was $44.66cd/m^2$ and was higher than that of $34cd/m^2$ of ZnO-NR at the same applied voltage of 4 V. Based on the experimental results, we could conclude that $TiO_2-NP$ is a more suitable electrode material in ECL device than the ZnO-NR.

• Journal of Powder Materials
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• v.24 no.3
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• pp.210-215
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• 2017

In this study, STS316L powders prepared by gas atomization are used to manufacture bulk structures with dimensions of $10{\times}10{\times}10mm^3$ using selective laser melting (SLM). The microstructures and hardness of the fabricated 316L stainless steel has been investigated with the laser beam overlap varied from 10% to 70%. The microstructures of the fabricated STS316L samples show a decrease in the balling and satellite of powders introducing defect in the bulk samples and the porosity caused by the gap between the molten metal pools disappearing as the overlap ratio increases, whereas a low overlap ratio results in significant balling and a large amount of isolated powders due to the increased gap between the melt pools. Furthermore, the highest value in Vickers hardness is obtained for the sample fabricated by 30% overlapped laser beams. These results show that the overlap ratio of laser beams in the SLM process should be considered as an important process parameter.

• Journal of Korean Foot and Ankle Society
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• v.14 no.2
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• pp.109-114
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• 2010

Purpose: The purpose of this study was to report the surgical outcome of reconstruction of neglected chronic Achilles tendon ruptures with various methods including Achilles tendon allograft. Materials and Methods: Between October 2003 and November 2008, 8 consecutive neglected chronic Achilles tendon ruptures with the defect gap of more than 4 cm underwent surgical reconstruction including V-Y advancement, gastrocnemius fascial turn-down flap, flexor hallucis longus transfer and Achilles tendon allograft. There were 7 males and 1 female who were evaluated at more than 18 months after surgery. At the time of followup, all patients were assessed with regard to postoperative complications, their self-reported level of satisfaction, the American Orthopaedic Foot and Ankle Society (AOFAS) Ankle-Hindfoot scale, 10 repetitive single heel rise, single leg hopping test, and ankle range of motion. Results: The AOFAS score increased from average 71.4 (50-87) to 96.4 (86-100). All patients were able to perform 10-repetitive single heel raise and single leg hopping at the latest follow up. No patient experienced wound complications and deep infection. Six patients were rated as 'excellent' and the other two as 'good'. Conclusion: Neglected chronic Achilles tendon ruptures could be successfully treated with careful selection of the reconstruction method according to the amount of defect gap. With an extensive defect, Achilles tendon allograft can be a good option when the reconstruction is not feasible otherwise.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2008.11a
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• pp.456-456
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• 2008

In the past few years, the deposition and characterization of cadmium sulfide semiconducting thin films has received a considerable amount of interest due to their potential application in the area of electronic and opto-electronic devices fabrications. Polycrystalline CdS thin films posses good optical transmittance, wide band-gap and electrical properties makes it as one of the ideal material for their application to solar cell fabrication. Cadmium sulfate thin films were deposited by the chemical bath deposition method using tartaric acid and triethanolamine as a complexing agent. Deposition parameters such as pH, temperature, deposition time and concentration of the reactant species were optimized so as to obtain reflecting, good adherent uniform thin films on the glass substrate. Reaction mechanism of the thin film formation is also reported. The crystallographic structure and the crystallite size were studied by the X-ray diffraction pattern. The optical band-gap of deposited film is identified by measuring the transmittance in the visible region. Temperature dependence of resistivity confirmed the semiconducting behavior of the film. Scanning electron micrographs (SEM) showed the presence of grain particles of size 50 nm.

• The Journal of Korean Medicine
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• v.39 no.2
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• pp.92-105
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• 2018

Objectives: This aim of this study is to compare the reflux esophagitis improvement effects of Sepiae Os, Arcae Concha, Ostreae Concha, and Proton Pump Inhibitor(esomeprazole) through rat experiments. Methods: NO production inhibitory effect was measured by NO production amount and iNOS mRNA expression level in cell lines. iNOS, $TNF-{\alpha}$ and $p-I{\kappa}B$, and serotonin were compared using immunohistochemistry at the rat reflux esophagitis. Reflux esophagitis connection external form, lower esophageal sphincter, and gap were observed and an esophageal inflammatory indicator, IL-6 activity was also evaluated by immunohistochemistry. Results: NO production and iNOS mRNA expression was showed concentration dependent decrease in cell lines treated with Sepiae OS, Arcae Concha, and Ostreae Concha at the experiments of cell lines. In the suppression of iNOS and $p-I{\kappa}B$ at the rat reflux esophagitis, Sepiae Os treat group(SOT) and Ostreae Concha treat group(OCT) were more effective. In the increase of serotonin at the rat reflux esophagitis, ACT, MT and OCT were more effective. Damage of lower esophageal sphincter, and gap between esophageal keratin and mucosa were observed less at the SOT, ACT, OCT. In the suppression of IL-6 at the rat reflux esophagitis, SOT and OCT were more effective than GE and, SOT was more effective than MT significantly. Conclusions: The anti-inflammatory effect was the best in the SOT and lower esophageal sphincter muscle contraction was the best in the ACT at the rat reflux esophagitis. Sepiae OS was more effective than esomeprazole in the suppression of iNOS, $TNF-{\alpha}$, and IL-6.

• Journal of environmental and Sanitary engineering
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• v.7 no.2
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• pp.53-68
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• 1992

Since 1962, Korea has made a remarkable progress with continuous success of Five-Year Economic Development Plans. Over the last 30 years, Korea has achieved a fast growth in various industries including heavy industry and chemical industry with rapid urbanization at the same time. The fast industrialization and urbanization brought about huge amount of hazardous/toxic substances and wastes. The environmental pollution problems have now emerged from regional concerns to overall social issues accordingly. The situation has come to a point where pollution control and environment preservation have become one of the nation's major policies. Following the recent Earth Summit of UNCED Conference held in Riode Janeiro in June 1992, where the topic was environmentally sound and sustainable development, awareness upon the importance of environmental preservation has been heightened globally, The environmental issues will gradually influence the international society more and more, politically as well as economically, The environmental pollution control industry in Korea started in the early 70's with the development of the nation's industrialization, As the people's awareness on pollution increases and environmental laws and enforcing regulations were established, demand for pollution control began to increase. The environmental pollution control business came to be recognized as an independent industry in the mid'70's. It should be evaluated properly that over the last 30 years, the Korean pollution control industry has supplied locally manufactured pollution control facilities to the increasing local demand. Concerning the quality and customer satisfaction, however, there are still many aspects which need to be improved compared with those of advanced countries. Although the start of the pollution control industry in Korea is just 10 to 15 years behind the advanced countries such as Japan and European countries, current gap in the environmental technology is rather considerable. And, studies should be made to find out the reasons for the current technology gap, and therefore, to implement solutions to improve the technology and competitiveness of the environmental pollution control industry in Korea.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.9 no.5
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• pp.1096-1101
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• 2005

An efficient method of estimating the spatial gaps between the connected components has been prposed to separatethe individual words from a handwritten legal amount on bank check. Owing to the inherent problem of underestimation or overestimation, the previous gap measures have much difficulty in being applied to the legal amounts that usually include the great shape variability by writer's unconstrained writing style and touching or irregular gaps between words by space limitation. In order to alleviate such burden and improve word separation performance, we have developed a modified version of each distance measure. Through a series of word separation experiments, we found that the modified distance measures show a better performance with over $2-3\%$ of the word separation rate than their corresponding original distance measures.

• Archives of Plastic Surgery
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• v.34 no.3
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• pp.285-290
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• 2007

Purpose: Many clinical trials have shown the effectiveness of platelet releasate on chronic wounds. However, a large volume of blood must be aspirated from a patient and a platelet separator is required. Here, we hypothesized that platelet concentrate obtained from a blood bank (PCBB) would be also effective at stimulating wound healing. The purpose of this study was to investigate the effectiveness of PCBB on accelerating healing of diabetic wounds in vivo. Methods: Round wounds of 5 mm diameter were made at four sites(two wounds on the left and two on the right side) on the backs of nine diabetic mice. Three hundred million platelets suspended in 0.05 ml fibrinogen were dispersed on each wound on left sides. Same amount of fibrinogen without platelets was dispersed on right side control wounds. Thereafter, 0.05 ml thrombin was applied to the each wound. Ten days after wound treatment, healed wounds were excised and the extent of wound healing in each group was compared. Results: Quantitative histologic analysis of epithelial gap distances revealed that PCBB treatment had greatly accelerated wound healing. Mean epithelial gap distances for PCBB treated and control wounds were $2.5{\times}0.6mm\;and\;3.6{\times}0.5mm$, respectively(p<0.05). Conclusion: Our results suggest that PCBB has potential to accelerate the healing of diabetic wounds.