• Clean Technology
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• v.26 no.3
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• pp.161-167
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• 2020

For the design of the prevention and mitigation measures in process industries involving flammable substances, reliable safety data are required. An important property used to estimate the risk of fire and explosion for a flammable liquid is the flash point. Flammability is an important factor to consider when developing safe methods for storing and handling solids and liquids. In this study, the flash point data were measured for the binary systems {2-butanol + 2,2,4-trimethylpentane}, {2-butanol + methylcyclohexane} and {2-butanol + toluene} at 101.3 kPa. Experiments were performed according to the standard test method (ASTM D 3278) using a Stanhope-Seta closed cup flash point tester. A minimum flash point behavior was observed in the binary systems as in the many cases for the hydrocarbon and alcohol mixture that were observed. The measured flash points were compared with the predicted values calculated via the following activity coefficient (GE) models: Wilson, Non-Random Two-Liquid (NRTL), and UNIversal QUAsiChemical (UNIQUAC) models. The predicted data were only adequate for the data determined by the closed-cup test method and may not be appropriate for the data obtained from the open-cup test method because of its deviation from the vapor liquid equilibrium. The predicted results of this work can be used to design safe petrochemical processes, such as the identification of safe storage conditions for non-ideal solutions containing flammable components.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.44 no.11
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• pp.48-53
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• 2007

In this paper, a high LO-RF isolation W-band MIMIC single-balanced mixer was designed and fabricated using a branch line coupler and a ${\lambda}/4$ transmission line. The W-band MIMIC single-balanced mixer was designed using the $0.1\;{\mu}m$ InGaAs/InAlAs/GaAs Metamorphic HEMT diode. The fabricated MHEMT was obtained the cut-off frequency($f_T$) of 154 GHz and the maximum oscillation frequency($f_{max}$) of 454 GHz. The designed MIMIC single-balanced mixer was fabricated using $0.1\;{\mu}m$ MHEMT MIMIC process. From the measurement, the conversion loss of the single-balanced mixer was 12.8 dB at an LO power of 8.6 dBm. P1 dB(1 dB compression point) of input and output were 5 dBm and -8.9 dBm, respectively. The LO-RF isolations of single-balanced mixer was obtained 37.2 dB at 94 GHz. We obtained in this study a higher LO-RF isolation compared to some other balanced mixers in millimeter-wave frequencies.

• Journal of the Microelectronics and Packaging Society
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• v.22 no.3
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• pp.19-23
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• 2015

In this study, two types of Au/TiW bump samples were fabricated by the electroplating process onto Al/Si and SiN/Si wafers for the COG (Chip On Glass) packaging. TiW was used as the UBM (Under Bump Metallurgy) material of the Au bump and it was deposited by a sputtering method under the sputtering powers ranges from 500 to 5000 Watt. We investigated the delamination phenomenas for the prepared samples as a function of the input sputtering powers. The stable interfacial adhesion condition was found to be 1500 Watt in sputtering power. In addition, the SAICAS (Surface And Interfacial Cutting Analysis System) measurement was used to find the adhesion strength of Au bumps for the prepared samples. TiW UBM films were deposited at the 1500 Watt sputtering power. As a results, there was a similar adhesion strengths between TiW/Au interfacial films on Al/Si and SiN/Si wafers. However, the adhesion strength of TiW UBM sputtering films on Al and SiN under films were 2.2 times differences, indicating 0.475 kN/m for Al/Si wafer and 0.093 kN/m for SiN/Si wafer, respectively.

• Journal of Distribution Science
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• v.16 no.12
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• pp.69-80
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• 2018

Purpose - Our primary goal of this study is to investigate the positive relationship between female managers' self-determined motivations (i.e., RAI: relative autonomy index) and job performances with the mediation of their job creativity in service industries. This study also examines the moderating role of creative efficacy on the relationship between female managers' self-determined motivations and creativities. Finally, based on mediation and moderation hypotheses, we also tested moderating effect of creative efficacy on the mediation effect of job creativity. Research design, data, and methodology - Drawing on SDT(Self-determination theory) and COR(conservation of resources) theories, we developed three research hypotheses. Service female managers from a several service organizations(i.e. banking, retailing, and restaurant/hospitality service) in South Korea were surveyed using self-administered instrument for data collection. A total of 331 usable questionnaires were obtained after list-wise deletion. To test reliability and validity of measurement model, we employed the CFA(confirmatory factor analysis) using M-plus 8.1 Software. Also, internal consistency was tested by Cronbach's α. We, furthermore, used the SPSS PROCESS MACRO 2.16, which was suggested by Hayes (2013; 2015), to test mediation, moderation, and moderated mediation. Results - Our results revealed that self-determined motivation and job performance were positively and fully mediated by job creativity. Furthermore, the positive relationship between female managers' self-determined motivations and job creativities was stronger when their creative self-efficacies were high than when it was low. In addition, female managers' creative self-efficacies also amplified the positive relationship between their self-determined motivations and job performances with the mediation of job creativity. Conclusions - Our research empirically elaborated the previous model of self-determined motivation and manager/female creativity literature by presenting the findings that female managers' self-determined motivations significantly influence their job performances via job creativity and that creative self-efficacy effectively strengthen these positive impacts. Also, our research offered new insight for practitioners (i.e. top service managers) by suggesting that they may enhance female service managers' job performance if they pay more attention to employee creativity in service marketing.

• Journal of Distribution Science
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• v.13 no.9
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• pp.81-93
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• 2015

Purpose - "Showrooming" refers to the phenomenon where a shopper visits a store to see and compare products but makes the purchase online at a lower price. Surveys on showrooming activities at home and abroad indicate that a significant number of consumers pursue showrooming activities. The advent of "showroomers," who engage in buying activities, hovering both on and offline, while selectively choosing sales channels to suit their needs, is powerful enough to erode the borders between channels and bring about seismic changes in the distribution industry. However, surprisingly, there has been no in-depth discussion on showrooming. This study seeks to theoretically investigate what impact personal characteristics have on showrooming preferences and attitudes in a multi-channel environment. Specifically, assumptions have been made that price perception, perceived performance risk, and trust in online shopping not only have a direct impact on showrooming attitudes but also indirectly affect it through the means of contact motivation. Research design, data, and methodology - To test the hypotheses, this study conducted a survey of male and female shoppers, ages 20 through 40s, who live in metropolitan areas, and have actively showroomed fashion items in the last six months. A clothing item usually purchased after a careful decision-making process was chosen as the target product of the study. The survey was conducted between October and November 2014, using a professional survey service provider. A total of 200 surveys were collected, of which 198 were used for analysis. Conceptual model Structural Equation Modeling (SEM) and Amos 18.0 were employed for data analysis and model verification. In addition, following the confirmatory factor analysis and measurement model analysis, the theoretical model that corresponds to the research model was analyzed. Results - Analysis results show that price perception, perceived performance risk, and trust in online shopping have a statistically significant and positive (+) impact on showrooming attitudes. In addition, in terms of the indirect influence of price perception and perceived performance risk on showrooming attitudes through means of contact motivation, price perception had a statistically significant and positive impact on means of contact motivation, whereas perceived performance risk did not have a statistically significant impact on it, with the relevant hypothesis rejected. Conclusions - These analysis results imply that the ultimate goal of consumers is to maximize their shopping benefits by selectively and strategically taking advantage of different channels in a complementary manner. This study presents many implications for distributors to encourage a deep understanding of showrooming consumers who have complicated consumption behaviors and to build channel integration strategies. This study has limitations in theoretical and practical implications. Therefore, subsequent studies need to focus on verifying that showrooming activities are based on reasonable and planned decisions by applying the theory of reasoned or planned behavior. In addition, the scope of the study should expand to include web showrooming, where consumers conduct product research online and purchase offline.

• Journal of the Korean Society of Radiology
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• v.10 no.6
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• pp.395-401
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• 2016

Upper gastrointestinal series is a diagnostic test that X-ray passes through the stomach after administering contrast media such as barium or gastrografin. Upper gastrointestinal series with an advantage of no side effect except temporary constipation or abdominal pain has been widely used to diagnose diseases of the gastrointestinal system. However, image degradation and diagnostic accuracy frequently occurred when improper movement and breath control were carried out by lack of understanding the overall inspection process for the upper gastrointestinal series. The movie of the upper gastrointestinal series was made for improving inspection accuracy and image quality. The examinees encouraged to see the movie for waiting time before doing upper gastrointestinal series. In this study, image quality and diagnostic accuracy was examined for the effect of the movie about upper gastrointestinal series. 60 patients composed of each 10 people from 30s to 80s were selected randomly among both 2,940 examinees in 2014 and 3,076 examinees in 2015. Image quality was evaluated by the full width at half maximum of profile for each image using the Image J. The measurement of the full width at half maximum showed 0.208 mm and 0.133 mm for after and before seeing the movie. Thus it was verified that the movie education could improve the image quality and diagnostic accuracy for upper gastrointestinal series.

• The Journal of Korean Academy of Prosthodontics
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• v.54 no.3
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• pp.210-217
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• 2016

Purpose: The aim of this study was to evaluate the marginal and internal adaptation of monolithic zirconia restoration made without physical model by digital intraoral scanner. Materials and methods: A prospective clinical trial was performed on 11 restorations as a pilot study. The monolithic zirconia restorations were fabricated after digital intraoral impression taking by intraoral scanner (TRIOS, 3shape, Copenhagen, Denmark), computer-aided designing, and milling manufacturing process. Completed zirconia crowns were tried in the patients' mouth and a replica technique was used to acquire the crown-abutment replica. The absolute marginal discrepancy, marginal gap, and internal gap of axial, line angle, and occlusal part were measured after sectioning the replica in the mesiodistal and buccolingual direction. Statistical analysis was performed using Kruskal-Wallis and Mann-Whitney U test (${\alpha}=.05$). Results: From the adaptation analysis by replica, the statistically significant difference was not found between mesiodistal and buccolingual sections (P>.05), but there was significant difference among the measurement location (P<.01). The amount of absolute marginal discrepancy was larger than those of marginal gap and internal gap (P<.01). Conclusion: Within the limitations of this study, the adaptation accuracy of model-free monolithic zirconia restoration fabricated by intraoral scanner exhibited clinically acceptable result. However, the margin of zirconia crown showed tendency of overcontour and cautious clinical application and follow up is necessary.

• The Journal of the Korea Contents Association
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• v.16 no.8
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• pp.508-516
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• 2016

With the rapid development of Social Network Service and with the diversification of user needs, new types of image-based SNS have emerged. Image-based SNS provides customized service to meet users' specified contents needs that have yet to be satisfied in conventional relation-based SNS like Facebook, leading the trend of service diversification. Unlike text-based SNS that has inconvenient view on a small mobile screen, image-based SNS provides the communication way focused on simple text message and image, and thus the main users of the image-based SNS are young people in their 20s who get accustomed to images, rather than text messages. Accordingly, the functions and roles of SNS UI have varied, and usability has been more important. With the users in their 20s who use image-based SNS, this study tried to look into the usability of the image-based SNS. To do that, heuristic evaluation method was applied to find UI problems. The main factors constituting usability were extracted, and user evaluation method was redesigned. Aside from the satisfaction measurement, this study conducted and analyzed a questionnaire survey with users in their 20s who used actual image-based SNS. This study analyzed usability factors that influenced of image-based SNS users. The analysis results are considered to be used as a fundamental material to improve usability in the process of developing social media service.

• Journal of the Korea Society of Computer and Information
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• v.20 no.3
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• pp.115-124
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• 2015

In this paper we analyse the previous (Quality of Services) and QoE(Quality of Experience) methods, and propose a high reliable network system framework and its service forwarding method that is able to provide seamless N-Screen services for proliferating disaster informations. The service satisfaction measurement, i.e., QoE, of contents consumers in N-screens services is going to be important the factor in disaster information proliferation because N-Screen services in the previous methods based on multi devices only focused on information transmission. The proposed system around these services is composed of a disaster information process framework for accepting user's service requirement, push service modules for minimizing the number of packets to be caused when carrying out the push service, and a push service controller for maximizing QoE measures. In order to provide a seamless N-Screen service on diverse screens, such as smartphone, PC, and big screen, we also have Open API(Application Programming Interface) functions. Through these results, we expect to evaluate QoS and QoE quality in the seamless N-Screen service.

• Journal of Distribution Science
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• v.17 no.10
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• pp.93-105
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• 2019

Purpose - First, empirical research will reveal how personal creativity affects the knowledge sharing and innovation behaviors of organizational members. Second, self-management competency will be verified to explain the causal relationship between independent and dependent variables as a mediating variable and to reduce the time interval. Research design, data, and methodology - There are two major research models. First, personal creativity (professionalism, emotional intelligence, internal motivation) has a positive impact on knowledge sharing (creation of knowledge, organization of knowledge, use of knowledge) and innovation behavior (deriving ideas, implementing ideas, promoting ideas). Second, self-management competency (intellectual capacity, emotional capacity, personality capacity) plays a mediating role. In addition to descriptive statistics and correlation analysis, Cronbach's α was calculated for 259 workers in the retail industry. In addition, confirmatory factor analysis was performed using the AMOS 24.0 program, and the influence on the measurement model was analyzed to verify the structural equation model. Results - First, personal creativity had a positive effect on knowledge sharing and innovation behavior. In other words, it was confirmed that the decision-making process accompanied by individual creativity can create an atmosphere of knowledge sharing and continue to innovate. Second, personal creativity had a positive effect on self-management competency, and self-management competency had a positive effect on knowledge sharing and innovation behavior. Third, self-management competency was found to partially mediate the influence of personal creativity on knowledge sharing and innovation behavior. Conclusions - First, it is important for managers to recognize the value of creative talents who can be a fundamental source of organizational success and competitive advantage, and to attract talented people. Second, managers should be able to develop decision-making processes to develop potential creativity and encourage creative ideas, opinions, or solutions when organizing the work environment of their members. Third, managers should promote the sharing and integration of new knowledge that underlies the creative views and attitudes of teams and organizational members. Unlike previous studies, which emphasize the role of the work environment in which creative behaviors are promoted, this study shows that creativity of individual members, itself, is an important determinant of knowledge sharing and innovation behavior.